Dissertations / Theses on the topic 'Power supply quality'

The history of applied superconductor-based equipment in industry, especially in power system, is briefly reviewed. The thesis presents a development of a superconducting magnetic energy storage system for power quality improvement and uninterruptible power supply (PQ/UPS SMES). The configuration of such a system and its control concept are analyzed in full details. Evaluation tests of an SMES system operating on a simple power system are presented and analyzed. They validate the applicability of such a system, as an attractive alternative for power quality improvement and uninterruptable power supply.
The PQ/UPS SMES system as well as the power network has been modeled using Matlab/Simulink simulation environment for convenience. The Simulink models of all relevant components are also presented. Finally, all the evaluation tests are also done in Simulink simulation environment.

In recent years, supply chain management (SCM) has become of great importance as nowadays not only are businesses competing with each other, but so too are suppliers. The main objective of this thesis is to analyse some of the relevant aspects of SCM found in the manufacturing processes and quality control methods of the supply chain in the wind power sector. This is done through a collection of articles which present and analyse real data collected in the field as well as empirical data. The subsequent results reveal that supply chains in the wind power sector are hybrids, where various manufacturing paradigms are in play (lean, agile,leagile and project management) at specific points of the purchasing and manufacturing process. This thesis analyses the lean manufacturing concept inside the wind power sector, revealing the extent to which the lean tools and techniques are applied and the impact they subsequently have on competing priorities. It also examines the difficulties encountered by service providers when attempting to implement lean concepts as well as those resulting from the complex technology required by this highly specialised sector. The thesis also highlights the fact that the widely-used ISO 9001 standard, valid in so many industrial sectors, falls short in sectors dealing with high technological complexity. Furthermore, it sheds light on the perception clients have concerning third-party audits. Lastly, the thesis demonstrates the wind sector’s extensive use of quality tools and techniques when compared to other industrial sectors. This thesis provides the starting point for analysing aspects related to manufacturing and quality management systems in the supply chains of sectors handling high technological complexity, where there is low volume manufacture, high levels of customised and mixed products and irregular demand.
El concepte de la gestió de la cadena de subministrament (SCM) ha anat guanyant importància en els darrers anys, donat que actualment ja no són les empreses les que competeixen entre elles, sinó que són les cadenes de subministrament les que competeixen entre si. El principal objectiu d'aquesta tesi, realitzada sota la modalitat de tesi doctoral per articles, és analitzar per mitjà de dades reals (dades de camp) i empíriques, alguns aspectes rellevants, relacionats amb la fabricació i la gestió de la qualitat, en la cadena de subministrament del sector eòlic. Els resultats d’aquest estudi mostren que la cadena de subministrament del sector eòlic, és una cadena "híbrida", on coexisteixen diferents paradigmes de fabricació (lean, agile, leagile i la gestió per projectes); amb diferents punts de penetració de comanda. Alhora en aquesta tesi, s´analitza el paradigma "lean manufacturing" des de la perspectiva del sector eòlic i ens posa de manifest les dificultats que troben els proveïdors i tecnòlegs del sector a l´hora d'implementar aquest paradigma. També en els resultats d´aquesta tesi es demostra que el popular estàndard de gestió de la qualitat ISO 9001, vàlid per a la majoria de sectors, és un estàndard insuficient quan es tracta d'implementar la gestió de la qualitat en sectors amb una alta complexitat tecnològica. Finalment també aquest treball demostra l'elevat ús de les eines i tècniques de qualitat en el sector eòlic, comparat amb altres sectors industrials. Finalment podem afirmar que aquesta tesi, constitueix un punt de partida per l'anàlisi de cadenes de subministrament en sectors d´alta tecnologia, on la demanda és incerta, amb baixos volums de fabricació i un alt grau de personalització en el “mix” de productes.

Thesis (D.Tech (Engineering Electrical)) - Central University of Technology, Free State, 2005
When Thomas Edison invented his carbon filament lamp in 1879, gas shares fell overnight. A committee of inquiry was set up to examine the future possibilities of the new method of lighting, and had reached the conclusion that electric light in the home was fanciful and absurd. Today electric light burns in practically every house in the civilised world, with many great advances in the production and use of electricity and electric power supplied by various utilities. The objective of the electric utility to deliver pure sinusoidal voltage at fairly constant magnitude throughout their system is complicated by the fact that there are currently loads on the system that produce harmonic voltages, which result in distorted voltages and currents that can adversely impact on the system performance in different ways. Because the numbers of harmonic producing loads have increased over the years, it has become necessary to address their influence, when making any additions or changes to an installation. Quality of supply measurements have long been used to characterise non-linearity on the power system, and have traditionally been measured with expensive portable analysers. A potentially faster, more integrated, and more flexible solution to measure the harmonics with a Supervisory System is accomplished by this research. Any script which aspired to cover in full detail the whole field of a subject so enormous as techniques to measure the quality of electricity supply on a SCADA system, would hardly be practical in less than a few volumes. The pretensions of this research are both modest and of a more immediate value to the reader.

Over the past decades, the concepts and methods for reliability assessment have evolved from analysing the ability of individual components to operate without faults and as intended during their lifetime, into the comprehensive approaches for evaluating various engineering strategies for system planning, operation and maintenance studies. The conventional reliability assessment procedures now receive different perspectives in different engineering applications and this thesis aims to improve existing approaches by incorporating in the analysis: a) a more detailed and accurate models of LV and MV networks and their reliability equivalents, which are important for the analysis of transmission and sub-transmission networks, b) the variations in characteristics and parameters of LV and MV networks in different areas, specified as “generic” UK/Scottish highly-urban, urban, sub-urban and rural network models, c) the relevant requirements for network reliability performance imposed by Regulators on network operators, d) the actual aggregate load profiles of supplied customers and their correlation with typical daily variations of fault probabilities and repair times of considered network components, and e) some of the expected “smart grid” functionalities, e.g., increased use of network automation and reconfiguration schemes, as well as the higher penetration levels of distributed generation/storage resources. The conventional reliability assessment procedures typically do not include, or only partially include the abovementioned important factors and aspects in the analysis. In order to demonstrate their importance, the analysis presented in the thesis implements both analytical and probabilistic reliability assessment methods in a number of scenarios and study cases with improved and more detailed “generic” LV and MV network models and their reliability equivalents. Their impact on network reliability performance is analysed and quantified in terms of the frequency and duration of long and short supply interruptions (SAIFI and SAIDI), as well as energy not supplied (ENS). This thesis addresses another important aspect of conventional approaches, which often, if not always, provide separate indicators for the assessment of system-based reliability performance and for the assessment of customer-based reliability performance. The presented analysis attempts to more closely relate system reliability performance indicators, which generally correspond to a fictitious “average customer”, to the actual “best-served” and “worst-served” customers in the considered networks. Here, it is shown that a more complex metric than individual reliability indicators should be used for the analysis, as there are different best-served and worst-served customers in terms of the frequency and duration of supply interruptions, as well as amounts of not supplied energy. Finally, the analysis in the thesis considers some aspects of the anticipated transformation of existing networks into the future smart grids, which effectively require to re-evaluate the ways in which network reliability is approached at both planning and operational stages. Smart grids will feature significantly higher penetration levels of variable renewable-based distributed generation technologies (with or without energy storage), as well as the increased operational flexibility, automation and remote control facilities. In this context, the thesis evaluates some of the considered smart grid capabilities and functionalities, showing that improved system reliability performance might result in a deterioration of power quality performance. This is illustrated through the analysis of applied automation, reconfiguration and automatic reclosing/remote switching schemes, which are shown to reduce frequency and duration of long supply interruptions, but will ultimately result in more frequent and/or longer voltage sags and short interruptions. Similarly, distributed generation/storage resources might have strong positive impact on system reliability performance through the reduced power flows in local networks and provision of alternative supply points, even allowing for a fully independent off-grid operation in microgrids, but this may also result in the reduced power quality levels within the microgrids, or elsewhere in the network, e.g. due to a higher number of switching transfers and transients.

In reregulated and restructured electricity markets the production and retail of electricity is conducted on competitive markets, the transmission and distribution on the other hand can be considered as natural monopolies. The financial regulation of Distribution System Operators (DSOs) has in many countries, partly as a consequence of the restructuring in ownership, gone through a major switch in regulatory policy. From applying regulatory regimes were the DSOs were allowed to charge their customers according to their actual cost plus some profit, i.e. cost-based regulation, to regulatory models in which the DSOs performance are valued in order to set the allowable revenue, i.e. Performance-Based Regulation (PBR). In regulatory regimes that value performance, the direct link between cost and income is weakened or sometimes removed. This give the regulated DSOs strong cost cutting incentives and there is consequently a risk of system reliability deterioration due to postponed maintenance and investments in order to save costs. To balance this risk the PBR-framework is normally complemented with some kind of quality regulation (QR). How both the PBR and QR frameworks are constructed determines the incentive that the DSO will act on and will therefore influence the system reliability development.

This thesis links the areas of distribution system reliability and performancebased regulation. First, the key incentive features within PBR, that includes the quality of supply, are identified using qualitative measures that involve analyses of applied regulatory regimes, and general regulatory policies. This results in a qualitative comparison of applied PBR models. Further, the qualitative results are quantified and analysed further using time sequential Monte Carlo simulations (MCS). The MCS enables detailed analysis of regulatory features, parameter settings and financial risk assessments. In addition, the applied PBRframeworks can be quantitatively compared. Finally, some focus have been put on the Swedish regulation and the tool developed for DSO regulation, the Network Performance Assessment Model (NPAM), what obstacles there might be and what consequences it might bring when in affect.

Cette thèse de doctorat porte sur les fluctuations temporelles du flux lumineux des lampes LED, ce phénomène portant le nom de papilottement (flicker). Le papillotement est habituellement considéré comme une perturbation en raison de son impact négatif sur la santé. Pour les systèmes d'éclairage à base de diodes électroluminescentes (LED), sa définition vient d'être formalisée dans la norme IEEE 1789:2015 et a été décrite pour les appareils alimentés en courant alternatif (CA). Ce papillotement alternatif résulte des interactions entre l'impédance du réseau, l'onde de tension, les courants harmoniques et le convertisseur de courant alternatif en courant continu (CA - CC). L'alimentation en courant continu est généralement obtenue via des convertisseurs à découpage. Par conséquent, les mêmes facteurs perturbateurs sont également présents sur les réseaux à courant continu. Cette thèse résume les diférences entre les propriétés caractéristiques du papillotement sous alimentation en CA et en CC. Il a été montré dans la littérature et aussi dans cette thèse qu'avec les LED, le facteur clé qui affecte le papillotement réside dans la conception du driver de LED - une partie indispensable des systèmes d'éclairage à LED. Cette thèse décrit une méthodologie d'évaluation de la sensibilité au papillotement des lampes LED sous alimentation en CC et analyse la façon dont cette sensibilité se modifie lorsque les drivers de LED sont simplifiés et adaptés à des alimentations CC. La thèse présente un ensemble d'expériences de mesure visant à déterminer la réaction typique du papillotement des lampes LED à la fois sous alimentation CA et CC. D'autres expériences ont été efectuées pour révéler l'impact de l'adaptation du driver à l'alimentation CC (en enlevant le pont redresseur à diodes). On constate que certaines lampes présentent une meilleure résistance au papillotement, tandis que d'autres lampes présentent une moindre résistance. Ces expériences sont accompagnées de simulations de drivers pour les lampes LED visant à reproduire et à expliquer les résultats des mesures. La thèse décrit en outre une expérience de mesure visant à montrer la sévérité typique de la variation de tension dans un réseau CC à basse tension couplé au CA domestique et son impact sur le papillotement. On conclut qu'un tel système est suisamment robuste pour filtrer les perturbations provenant du CA, mais une interaction indésirable entre la lampe et l'alimentation peut se produire
This dissertation thesis is concerned with temporal fluctuations of the luminous flux of LED lamps, a phenomenon referred to as flicker. Flicker is usually regarded as a disturbance due to its negative impact on human health. For lighting systems based on light emitting diodes (LED), its definition has recently been formalised in norm IEEE 1789-2015 and has been documented on devices supplied with AC voltage. AC flicker results from interactions between network impedance, voltage and current harmonics, and the AC to DC converter. DC supplies are generally obtained by switching converters. Consequently, the same perturbing factors are present on DC networks. The thesis summarises the differences between the characteristic properties of flicker under AC and DC supplies. It has been shown in the literature and also in this thesis that the key factor affecting flicker with LEDs is the design of the LED driver-a necessary part of the LED lighting systems. This thesis describes a methodology for the evaluation of the flicker sensitivity of DC supplied LED lamps and analyses how the sensitivity changes when the LED drivers are simplified and accustomed to DC supply. The thesis presents a set of measurement experiments aimed to determine the typical flicker response of LED lamps both under AC and DC supply. Further experiments were performed to reveal the impact of accustomising the driver to the DC supply (removing the diode rectifier). It was found that some lamps show better flicker immunity while other lamps show worse flicker immunity. These experiments are accompanied by LED driver simulations aiming to reproduce and explain the measurement results. The thesis further describes a measurement experiment aimed to show the typical severity of the voltage fluctuation in a low voltage DC network coupled to AC mains and its impact on the flicker. It is concluded that such a system is robust enough to filter out any perturbations coming from the AC supply, but an undesired interaction between the lamp and the supply may occur

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.14.02 – електричні станції, мережі і системи. Національний технічний університет "Харківський політехнічний інститут", Харків, 2017. В дисертаційній роботі розроблений метод розрахунку фактичних значень перетікань реактивної потужності в системі електропостачання промислових підприємств шляхом застосування інформаційної бази автоматизованих систем обліку електроенергії для випадку, коли межа балансової належності знаходиться на стороні вищої напруги силових трансформаторів, а розрахункові прилади обліку встановлені на стороні низької напруги. Знайшов подальший розвиток метод розрахунку сталого режиму роботи конденсаторних установок при наявності джерел вищих гармонік. Розроблені критерії оптимізації перетікань реактивної потужності для різних джерел реактивної потужності та їх комбінацій. Визначені засоби та заходи, що унеможливлюють виникнення резонансних явищ в мережі під час пуску нелінійного навантаження, яке вмикається паралельно конденсаторній установці.
The thesis is for obtaining scientific degree candidate of technical sciences in specialty 05.14.02 – Еlectrical power stations, networks and systems. National Technical University of Ukraine "Kharkov Polytechnic Institute", Kharkov, 2017. The method of calculating the actual values of reactive power flows in power systems of industrial enterprises with varied load was developed in the thesis. This was done by applying the database of automated accounting systems of electric power under conditions, when the balance limit is on the side of high voltage of power transformers and computational metering devices are installed on the side of low voltage. Criteria of reactive power flows optimization for each reactive power source and their combinations were developed. The method of calculating the established operating mode of capacitor bank with the source of higher harmonics was improved by determination the resonant frequency and creation dependence of the impedance absolute value on the number of higher harmonics in the network in order to prevent resonance of currents at higher odd harmonics that are multiples of 50 Hz. The number of working asynchronous electric motors in the group of the same type in real time was determined. Tools and actions which exclude resonance emergence in the power supply system, with working capacitor banks during the startup regime of nonlinear load were developed.

Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.09.03 – Електротехнічні комплекси та системи. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2019. У роботі міститься вирішення актуальної наукової проблеми аналізу якості електропостачання та електромагнітної сумісності електротехнічних комплексів та систем. Ця проблема полягає у відсутності математичної бази та, відповідно, нормативної бази оцінювання впливу окремого електротехнічного комплексу або системи споживача на якість електроенергії. Діючи норми покладають усю відповідальність за низьку якість електропостачання на безпосередньо постачальну організацію у вигляді штрафів, що, як показує досвід, не сприяє побудові оптимальних систем електропостачання. В роботі запропоновано оцінку якості електропостачання шляхом порівняння режиму електроспоживання діючого електротехнічного комплексу з еталонним споживачем у вигляді числових коефіцієнтів потужності та втрат. Отримані розрахункові формули для однофазних, трифазних трипровідних та чотирьохпровідних систем електропостачання. Запропоновано розподіл загальних втрат на втрати від несиметрії, не лінійності, реактивності та нестаціонарності. Запропоновано та досліджено концепції еталонного реактивного споживача та усередненого реактивного споживача. Запропоновано методику врахування якості електроспоживання при розрахунках за спожиту електроенергію, яка створює економічний стимул для підвищення ефективності енергорежимів споживача. Запропоновано методику оцінки порушення споживачем норм споживання за величиною потужності і гармонійних складових, що потенційно здатні викликати вихід показників якості електричної енергії за допустимі межі. Надано основи методики побудови штрафних санкцій щодо споживача у разі перевищення допустимих параметрів електроспоживання, а також штрафних санкцій щодо постачальника електричної енергії у разі низької якості електричної енергії та відсутності порушень з боку споживача.
The dissertation on achieving the scientific degree Doctor of Technical Sciences by specialty 05.09.03 – "Electrotechnical complexes and systems" - National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2020. The paper contains the solution of the actual scientific problem of the analysis of quality of power supply and electromagnetic compatibility of electrotechnical complexes and systems. This problem is the lack of a mathematical basis and, accordingly, a regulatory framework for assessing the impact of a particular electrical complex or consumer system on the quality of electricity. The current regulations place all responsibility for the low quality of electricity supply directly on the supply organization in the form of fines, which, as experience shows, does not contribute to the construction of optimal power supply systems. The paper analyzes the compatibility of the existing regulatory framework (including IEEE519, EN50160) and evaluates the effectiveness of the proposed methods of determining responsibility using computer simulations. The analysis showed that the existing methods have significant limitations, as a result of which they are not suitable for practical application. The paper proposes an assessment of the quality of power supply by comparing the mode of power consumption of the existing electrical complex with the reference consumer in the form of numerical coefficients of power and losses. Calculation formulas for single-phase, three-phase three-wire and four-wire power supply systems are obtained. Three-phase three-wire system the reference consumer, regardless of the voltage parameters, is a symmetrical triangle of constant active resistance is shown. Three-phase four-wire system the reference consumer, regardless of voltage parameters, is a combination of a symmetric triangle of constant active resistances and a symmetrical star, the resistance in the branches of which is as many times more than the resistance of the triangle is shown. It is noted that the general assessment of the loss ratio is not informative enough about the reasons for the deterioration of electricity quality. To solve this problem, the division of total losses into losses from asymmetry, nonlinearity, reactivity and nonstationarity is proposed. The concept of the reference reactive consumer is offered, and conclusions concerning possibility and expediency of its use are made. A method for determining the reactivity coefficient by volumes of energy flowing in the forward and reverse directions is proposed. The concept of the average reactive consumer is offered. The paper proposes to build an assessment of the contribution of a separate electrical complex or consumer system in the deterioration of power supply on the basis of power values specified in the contract and the establishment of normalized resistance of the power supply system. Based on these values, a mathematical apparatus is proposed, which allows not only to determine the fact of violation of the limits of electromagnetic compatibility but also to quantify the amount of electricity that has been damaged. It is proposed to determine the coefficient of losses from asymmetry using a reference consumer. This coefficient is calculated as the ratio between the power loss of three independent single-phase reference consumers to the losses of the reference three-phase consumer. This solution avoids the influence of such factors as nonlinearity and reactivity. In addition, the device of symmetrical components is not used, which is inconvenient in the case of non-sinusoidal voltages and currents. It is proposed to select individual coefficients of losses from reactivity and nonlinearity, which are calculated by dividing the harmonic components of the distortion current by the power direction. The method of calculation of losses from nonstationarity is calculated, which is calculated as the ratio of total losses of reference consumers on several "short" intervals, and losses of the reference consumer on a long interval that includes all "short". The analysis of character of complex resistance of an electric network depending on parameters of its elements for typical cases of connection of consumers of various character on voltage of 10 KV is carried out. The obtained dependence allows us to talk about the possible use of normalized values to estimate network bandwidth. An empirical method for calculating the normalized resistance is proposed. A method for measuring the parameters of the electrical network mode is proposed, which allows to implement algorithms for assessing the quality of power consumption, the advantages of which are self-synchronization, calculation of values strictly for one period of the main voltage harmonic, absence of gaps and overlays of observation intervals. A method for measuring the current values of currents and voltages on their discrete images is proposed, taking into account the discrepancy between the moments of the initial and final readings of the digital image of the signal with the moments of the beginning and end of the measurement period. A method of taking into account the quality of electricity consumption in the calculations for the consumed electricity is proposed, which creates an economic incentive to increase the efficiency of energy regimes of the consumer. The method of estimation of infringement by the consumer of norms of consumption on size of power and harmonic components which are potentially capable to cause an exit of indicators of quality of electric energy beyond admissible limits is offered. The basics of the method of construction of penalties against the consumer in case of exceeding the allowable parameters of electricity consumption, as well as penalties against the supplier of electricity in case of low quality of electricity and the absence of violations by the consumer. In the experimental part of the work the application of the offered mathematical devices on the examples of test mathematical models and oscillograms obtained on real objects is tested. The experiment allowed to confirm the effectiveness of the proposed methods, in addition to the method of comparison with the reference medium-reactive consumer, which has not proved to be an effective tool for analysis and does not seem promising. Also in the work the hardware realization in the form of the electric energy meter taking into account its quality is offered.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.14.02 – електричні станції, мережі і системи. Національний технічний університет "Харківський політехнічний інститут", Харків, 2017. В дисертаційній роботі розроблений метод розрахунку фактичних значень перетікань реактивної потужності в системі електропостачання промислових підприємств шляхом застосування інформаційної бази автоматизованих систем обліку електроенергії для випадку, коли межа балансової належності знаходиться на стороні вищої напруги силових трансформаторів, а розрахункові прилади обліку встановлені на стороні низької напруги. Знайшов подальший розвиток метод розрахунку сталого режиму роботи конденсаторних установок при наявності джерел вищих гармонік. Розроблені критерії оптимізації перетікань реактивної потужності для різних джерел реактивної потужності та їх комбінацій. Визначені засоби та заходи, що унеможливлюють виникнення резонансних явищ в мережі під час пуску нелінійного навантаження, яке вмикається паралельно конденсаторній установці.
The thesis is for obtaining scientific degree candidate of technical sciences in specialty 05.14.02 – Еlectrical power stations, networks and systems. National Technical University of Ukraine "Kharkov Polytechnic Institute", Kharkov, 2017. The method of calculating the actual values of reactive power flows in power systems of industrial enterprises with varied load was developed in the thesis. This was done by applying the database of automated accounting systems of electric power under conditions, when the balance limit is on the side of high voltage of power transformers and computational metering devices are installed on the side of low voltage. Criteria of reactive power flows optimization for each reactive power source and their combinations were developed. The method of calculating the established operating mode of capacitor bank with the source of higher harmonics was improved by determination the resonant frequency and creation dependence of the impedance absolute value on the number of higher harmonics in the network in order to prevent resonance of currents at higher odd harmonics that are multiples of 50 Hz. The number of working asynchronous electric motors in the group of the same type in real time was determined. Tools and actions which exclude resonance emergence in the power supply system, with working capacitor banks during the startup regime of nonlinear load were developed.

The ability of a piezoelectric transducer in energy conversion is rapidly expanding in several applications. Some of the industrial applications for which a high power ultrasound transducer can be used are surface cleaning, water treatment, plastic welding and food sterilization. Also, a high power ultrasound transducer plays a great role in biomedical applications such as diagnostic and therapeutic applications. An ultrasound transducer is usually applied to convert electrical energy to mechanical energy and vice versa. In some high power ultrasound system, ultrasound transducers are applied as a transmitter, as a receiver or both. As a transmitter, it converts electrical energy to mechanical energy while a receiver converts mechanical energy to electrical energy as a sensor for control system. Once a piezoelectric transducer is excited by electrical signal, piezoelectric material starts to vibrate and generates ultrasound waves. A portion of the ultrasound waves which passes through the medium will be sensed by the receiver and converted to electrical energy. To drive an ultrasound transducer, an excitation signal should be properly designed otherwise undesired signal (low quality) can deteriorate the performance of the transducer (energy conversion) and increase power consumption in the system. For instance, some portion of generated power may be delivered in unwanted frequency which is not acceptable for some applications especially for biomedical applications. To achieve better performance of the transducer, along with the quality of the excitation signal, the characteristics of the high power ultrasound transducer should be taken into consideration as well. In this regard, several simulation and experimental tests are carried out in this research to model high power ultrasound transducers and systems. During these experiments, high power ultrasound transducers are excited by several excitation signals with different amplitudes and frequencies, using a network analyser, a signal generator, a high power amplifier and a multilevel converter. Also, to analyse the behaviour of the ultrasound system, the voltage ratio of the system is measured in different tests. The voltage across transmitter is measured as an input voltage then divided by the output voltage which is measured across receiver. The results of the transducer characteristics and the ultrasound system behaviour are discussed in chapter 4 and 5 of this thesis. Each piezoelectric transducer has several resonance frequencies in which its impedance has lower magnitude as compared to non-resonance frequencies. Among these resonance frequencies, just at one of those frequencies, the magnitude of the impedance is minimum. This resonance frequency is known as the main resonance frequency of the transducer. To attain higher efficiency and deliver more power to the ultrasound system, the transducer is usually excited at the main resonance frequency. Therefore, it is important to find out this frequency and other resonance frequencies. Hereof, a frequency detection method is proposed in this research which is discussed in chapter 2. An extended electrical model of the ultrasound transducer with multiple resonance frequencies consists of several RLC legs in parallel with a capacitor. Each RLC leg represents one of the resonance frequencies of the ultrasound transducer. At resonance frequency the inductor reactance and capacitor reactance cancel out each other and the resistor of this leg represents power conversion of the system at that frequency. This concept is shown in simulation and test results presented in chapter 4. To excite a high power ultrasound transducer, a high power signal is required. Multilevel converters are usually applied to generate a high power signal but the drawback of this signal is low quality in comparison with a sinusoidal signal. In some applications like ultrasound, it is extensively important to generate a high quality signal. Several control and modulation techniques are introduced in different papers to control the output voltage of the multilevel converters. One of those techniques is harmonic elimination technique. In this technique, switching angles are chosen in such way to reduce harmonic contents in the output side. It is undeniable that increasing the number of the switching angles results in more harmonic reduction. But to have more switching angles, more output voltage levels are required which increase the number of components and cost of the converter. To improve the quality of the output voltage signal with no more components, a new harmonic elimination technique is proposed in this research. Based on this new technique, more variables (DC voltage levels and switching angles) are chosen to eliminate more low order harmonics compared to conventional harmonic elimination techniques. In conventional harmonic elimination method, DC voltage levels are same and only switching angles are calculated to eliminate harmonics. Therefore, the number of eliminated harmonic is limited by the number of switching cycles. In the proposed modulation technique, the switching angles and the DC voltage levels are calculated off-line to eliminate more harmonics. Therefore, the DC voltage levels are not equal and should be regulated. To achieve this aim, a DC/DC converter is applied to adjust the DC link voltages with several capacitors. The effect of the new harmonic elimination technique on the output quality of several single phase multilevel converters is explained in chapter 3 and 6 of this thesis. According to the electrical model of high power ultrasound transducer, this device can be modelled as parallel combinations of RLC legs with a main capacitor. The impedance diagram of the transducer in frequency domain shows it has capacitive characteristics in almost all frequencies. Therefore, using a voltage source converter to drive a high power ultrasound transducer can create significant leakage current through the transducer. It happens due to significant voltage stress (dv/dt) across the transducer. To remedy this problem, LC filters are applied in some applications. For some applications such as ultrasound, using a LC filter can deteriorate the performance of the transducer by changing its characteristics and displacing the resonance frequency of the transducer. For such a case a current source converter could be a suitable choice to overcome this problem. In this regard, a current source converter is implemented and applied to excite the high power ultrasound transducer. To control the output current and voltage, a hysteresis control and unipolar modulation are used respectively. The results of this test are explained in chapter 7.

Диссертация на соискание ученой степени доктора технических наук по специальности 05.09.03 - электротехнические комплексы и системы. - Национальный технический университет "Харьковский политехнический институт". - Харьков, 2015. Диссертационная работа посвящена решению важной научно-технической проблемы создания обобщенной теории мощности (ТМ), единого комплексного подхода к компенсации и учету неактивных составляющих полной мощности (ПМ) для обеспечения оптимального режима потребления электрической энергии (ЭЭ) в точке подключения неидеальной нагрузки к сети с несимметричным напряжением. На основе теоретических исследований, использующих метод ортогонального разложения векторов мгновенных значений 3-фазного тока и напряжения, получена обобщенная векторная математическая модель (ВММ), которая классифицирует электроэнергетические режимы (ЭР) в 3-фазной схеме электроснабжения с помощью векторной мгновенной мощности (ММ). Сформулированы и обоснованы предложения политики повышения качества поставки и потребления электроэнергии в 3-фазной сети, сочетающие установку поставщиком в каждой точке подключения потребителя счетчика, измеряющего каждую ЭКТ, заключение публичного договора, в котором предусмотрена оплата каждой ЭКТ по своему тарифу, установки потребителем КУ, применение компенсации неактивных составляющих ПМ на каждом уровне для уменьшения групповых потерь в сетях поставщика. Предложенная политика позволит учесть разную степень влияния ЭКТ на качество электроэнергии и обеспечит потребителю выбор выгодного для него способа потребления электроэнергии, стимулирует установку КУ, а поставщику обеспечит надежную методологию повышения качества электроэнергии в рамках несимметрии нагрузки и напряжения.
Thesis for a Doctor’s degree in Engineering Sciences by specialty 05.09.03 - Electrical Engineering Complexes and Systems. - National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2015. The dissertation is devoted an important scientific and technical issues to improve the power quality of supply and consumption (SC) in three-phase networks through further development of die power theory, development of methods and ways of compensation, proposals for the accounting and payment of the inactive components of the apparent power (AP). A generalized mathematical model (GMM) of electric power processes (EPP) in a 3-phase SC scheme was developed. The model of 3-wire circuit is provided by a special (О-balanced) mode of the model 4-wire circuit The developed GMM classifies the SC modes using the vectorial instantaneous power (IP) and summarizes the class of models used in the theory of IP. For sinusoidal mode with asymmetric voltage the refines vectorial mathematical model (VMV) 3-phasors (complex rms vectors) was created. The analytical expressions for the integral characteristics of the classified modes are founded and their relationship with standard IP and vectorial IP are established. With asymmetrical voltage and asymmetrical loading a sinusoidal mode can be both unbalanced and pulsed. Each mode is represented by its power equation and the equivalent orthogonal decomposition of the 3-phase current Both decompositions are used to create the optimal mode of SC with a constant IP at asymmetrical voltage. The proposed compensator provides the non-puised energy supply with the highest possible power factor and with the same average (active) power as the initial current. Based on the evaluation and calculation of the power equation components of a unbalanced mode was developed a methodology for calculating the loss of the measuring selection. A methodology and technique of analytical calculation of additional losses on the passport data of the connected electrical equipment was proposed. Formulated and proved offers on differential measurement and payment of the energy components of AP will stimulate consumer sets the compensator, and provide a reliable methodology for improving the quality of SC (within unbalance loading and voltage).

Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.09.03 – "Електротехнічні комплекси та системи". – Національний технічний університет "Харківський політехнічний інститут", Харків, 2019. У дисертаційній роботі вирішується важлива науково-технічна проблема підвищення якості електропостачання електротехнічних об'єктів, комплексів та систем і забезпечення їх електромагнітної сумісності шляхом розвитку математичного та апаратного забезпечення систем обліку електроенергії з урахуванням енергетичної ефективності режимів електроспоживання і виявлених порушень меж електромагнітної сумісності з боку постачальника електричної енергії або її споживача. У вступі визначено існуючу проблему і обґрунтовано актуальність теми дисертації, наведено зв'язок роботи з науковими програмами, планами, темами, сформульовано мету і завдання наукового дослідження, розглянуто об'єкт та предмет досліджень, наведено перелік методів дослідження, що застосовувалися для досягнення поставленої мети роботи. Викладено наукову новизну й практичну значущість отриманих результатів, наведено дані про публікації й апробацію результатів роботи, охарактеризовано особистий внесок здобувача, надано відомості про впровадження результатів роботи. У першому розділі на підставі вивчення та систематизації результатів аналізу матеріалів з відкритих джерел сформульовані основні недоліки існуючих методів оцінки якості електропостачання та нормативної бази, яка не дозволяє у повному обсязі вирішувати конфліктні ситуації при виникненні порушень меж електромагнітної сумісності у розрізі електропостачальник-споживач. Також розглянуті методи визначення відповідальності за погіршення якості електричної енергії та окремих її показників. У другому розділі проведено аналіз типової схеми електропостачання, що дозволило зробити висновки та отримати основні числові характеристики системи електропостачання трифазного електротехнічного об'єкту з напругою живлення 10 кВ. За допомогою комп’ютерної моделі показано взаємний вплив декількох споживачів на показники якості напруги у точці приєднання та проаналізовано вплив параметрів системи електропостачання ці показники. Показано, що визначення джерела вищих гармонік за напрямком складової потужності вищої гармоніки не дозволяє гарантовано виділити споживача з нелінійним навантаженням у разі якщо кількість таких споживачів більша за одного. Також проаналізовано сумісність стандартів EN 50160 та IEEE 519 з точки зору норми рівнів гармонійних складових у складі струму та напруги. Отримані результати дозволяють говорити про наявність окремих моментів в яких вищи гармонійні складові струму, що генерує споживач не порушуючи меж стандарту IEEE 519, можуть викликати наявність гармонік напруги що перевищують норми установлені EN 50160. Також зроблено висновки щодо встановлення обмежень генерації вищих гармонійних складових за допомогою нормованих значень опору системи. У третьому розділі запропоновано подальший розвиток математичного апарату визначення коефіцієнтів потужності та втрат, як показників якості електроспоживання, зокрема обґрунтовані визначення інтегральних коефіцієнтів втрат для трифазних трипровідних та чотирьохпровідних мереж. Отримала подальший розвиток теорія "еталонного" споживача. Показано, що в трифазній трипровідній мережі еталонним споживачем незалежно від параметрів напруги є симетричний трикутник постійних активних опорів. Показано, що в трифазній чьотирьохпровідній системі еталонним споживачем незалежно від параметрів напруги є поєднання симетричного трикутника постійних активних опорів і симетричної зірки, опір в гілках якої в стільки ж разів більше опорів трикутника, у скільки разів активний опір провіднику нейтралі більше опору фазних провідників. Вперше запропоновано математичний апарат виділення окремих складових із загальних коефіцієнтів потужностей та втрат за такими типами спотворень як несиметрія, нелінійність, реактивність та нестаціонарність. Запропоновано концепцію еталонного реактивного споживача з умов максимуму потужності або мінімуму втрат при рівності співвідношень перетоків потужності від і до споживача, що дозволяє реалізувати обчислення коефіцієнту реактивності та потужності при довільній формі напруги у однофазних та трифазних мережах. Показано, що при такій постановці еталонний реактивний споживач тяжіє до генерації вищих гармонік і не має зручного аналітичного або чисельного рішення для порівняння з поточним споживачем. Запропоновано концепцію середньореактивного споживача, у якого усі гармоніки мають рівне співвідношення перетікань потужності до і від споживача, що дозволяє реалізувати порівняння режиму електроспоживання поточного споживача з таким середньореактивним. Запропоновано методику оцінки коефіцієнтів втрат і потужності від несиметрії для трифазного споживача при довільній напрузі. Запропоновано методику оцінки співвідношення коефіцієнтів втрат від реактивності і нелінійності споживача шляхом поділу відповідних гармонік струму Фризе у напрямку активної складової. Запропоновано методику оцінки коефіцієнтів втрат і потужності від нестаціонарності споживання. У четвертому розділі проведено аналіз характеру комплексного опору електричної мережі в залежності від параметрів її елементів для типових випадків підключення споживачів на напрузі 10 КВ. Отримана залежність дозволяє говорити про можливе застосування нормованих значень для оцінки пропускної здатності мережі. Набув подальшого розвитку метод вимірювання електричних параметрів трифазної мережі заснований на апроксимації вхідного сигналу сумою гармонійних складових. Особливостями методу є автоматичне підстроювання по частоті і тривалості інтервалу спостереження у заданому діапазоні, використання повного набору напруг фаз (або лінійних) при визначенні частоти з урахуванням їх вагових значень, що дозволяє зменшити похибки вимірювання у складних умовах – при наявності несиметрії, вищих гармонік, аперіодичної складової або при відсутності напруги у окремій фазі. Крім того, метод вимірювання використовує постійну частоту квантування вхідних цифрових даних, що дозволяє спростити апаратну частину приладу. Запропоновано метод обчислення діючих значень з точною прив'язкою до періоду напруги, одержуваного попереднім методом, що дозволяє виключити частотну похибку при вимірюванні незалежно від розташування початку та закінчення інтервалу спостереження відносно відліків вхідного цифрового сигналу. Запропоновано систему обліку електричної енергії з використанням показників якості електричної енергії та ефективності електроспоживання. Особливістю системи є додатковий облік втрат на передачу електричної енергії шляхом порівняння характеристик електроспоживання поточного споживача з такими для еталонного споживача, тобто використання коефіцієнтів втрат або потужності. Такий метод обліку дозволяє коректно тарифікувати всі відхилення в режимах роботи навантаження, такі як реактивність, нелінійність і нестаціонарність. Запропоновано систему штрафних санкцій за погіршення якості електричної енергії, заснована на підрахунку "штрафної" енергії в разі, якщо споживач порушує норми електроспоживання і "нетарифікованої" енергії, в разі коли порушень з боку споживача немає, але якість електроенергії не відповідає нормам. Запропоновано основи тарифікації на базі даної системи обліку електроенергії. У п'ятому розділі експериментально отримані дані, що підтверджують теоретичні положення розділів 3 та 4. Зокрема були реалізовані оцінки якості електроспоживання шляхом порівняння з набором еталонних споживачів. Експеримент показав можливість успішного застосування виділення струму Фрізе і його подальшого аналізу з метою оцінки якості електроспоживання. При цьому можливе паралельне використання його трифазної і однофазної реалізацій для оцінки несиметрії, нелінійності і реактивності відповідно. Запропонована в розділі 3 методика порівняння з еталонним среднереактівним споживачем не виявила себе в якості ефективного інструменту аналізу і не представляється перспективною. У той же час поділ гармонійних складових струму Фрізе у напрямку їх активної складової дозволяє ефективно відстежувати джерело походження струмів вищих гармонік. Визначені вище методи з використанням моделі фрагменту енергосистеми з різними типами навантаження підтвердили коректність розроблених методів оцінки якості електроспоживання. Випробування за допомогою осцилограм, отриманих на реальних трифазних навантаженнях (тягової підстанції) також підтвердило працездатність та ефективність розроблених методів оцінки. В моделях з перевищенням допустимих режимів, використання математичного апарату розробленого в розділі 4 дозволило виявити джерело спотворень, навіть за умови коли одночасно декілька споживачів виступають в якості джерел цих спотворень.
The dissertation on competition of a scientific degree of the doctor of technical sciences on a specialty 05.09.03 - "Electrotechnical complexes and systems". - National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2019. In the dissertation the important scientific and technical problem of increase of quality of power supply of electrotechnical objects, complexes and systems and maintenance of their electromagnetic compatibility by development of mathematical and hardware of systems of the account of the electric power taking into account energy efficiency of modes of power consumption and the revealed infringements of electromagnetic compatibility energy or its consumer. In the introduction the existing problem is defined and the urgency of the dissertation topic is substantiated, the connection of work with scientific programs, plans, themes is given, the purpose and tasks of scientific research are formulated, the object and subject of researches are considered, the list of research methods applied for achievement of the set purpose is given work. The scientific no velty and practical significance of the obtained results are stated, the data on publications and approbation of the results of the work are given, the personal contribution of the applicant is characterized, the information on the implementation of the results of the work is given. In the first section, based on the study and systematization of the results of analysis of materials from open sources, the main shortcomings of existing methods of assessing the quality of electricity supply and regulatory framework, which does not fully resolve conflict situations in violation of electromagnetic compatibility in terms of electricity supplier - consumer. Methods for determining the responsibility for the deterioration of electricity quality and its individual indicators are also considered. The second section analyzes the typical power supply scheme, which allowed to draw conclusions and obtain the main numerical characteristics of the power supply system of a three-phase electrical facility with a supply voltage of 10 kV. The computer model shows the mutual influence of several consumers on the quality indicators of the voltage at the point of connection and analyzes the influence of the parameters of the power supply system, these indicators. It is shown that the definition of the source of higher harmonics in the direction of the component power of the higher harmonic does not guarantee to allocate a consumer with a nonlinear load if the number of such consumers is greater than one. The compatibility of EN 50160 and IEEE 519 standards in terms of the norm of levels of harmonic components in the composition of current and voltage is also analyzed. The obtained results allow to speak about the presence of certain moments in which the higher harmonic components of the current generated by the consumer without violating the IEEE 519 standard can cause the presence of voltage harmonics exceeding the norms set by EN 50160. It is also concluded that the generation of higher harmonic components system resistance values. The third section proposes further development of the mathematical apparatus for determining power and loss coefficients as indicators of power consumption quality, in particular, the determination of integrated loss coefficients for three-phase three-wire and four-wire networks is substantiated. The theory of the "reference" consumer was further developed. It is shown that in a three-phase three-wire network the reference consumer, regardless of the voltage parameters, is a symmetrical triangle of constant active resistances. It is shown that in a three-phase four-wire system the reference consumer, regardless of voltage parameters, is a combination of a symmetric triangle of constant active resistances and a symmetric star, the resistance in the branches of which is as many times the resistance of the triangle as the active resistance of the neutral conductor. For the first time, a mathematical apparatus for selecting individual components from the total power and loss coefficients for such types of distortions as asymmetry, nonlinearity, reactivity and nonstationarity has been proposed. The concept of the reference reactive consumer from the conditions of maximum power or minimum losses at equality of ratios of power flows from and to the consumer is offered, that allows to realize calculation of coefficient of reactivity and power at any form of voltage in single-phase and three-phase networks. It is shown that in such a statement the reference reactive consumer tends to generate higher harmonics and does not have a convenient analytical or numerical solution for comparison with the current consumer. The concept of the average reactive consumer is proposed, in which all harmonics have an equal ratio of power flows to and from the consumer, which allows to compare the current consumption mode of the current consumer with such an average reactive one. A method for estimating the coefficients of loss and power from asymmetry for a three-phase consumer at arbitrary voltage is proposed. A method for estimating the ratio of the coefficients of losses from reactivity and nonlinearity of the consumer by dividing the corresponding harmonics of the Frieze current in the direction of the active component is proposed. A method for estimating the coefficients of losses and power from non-stationary consumption is proposed. In the fourth section the analysis of character of complex resistance of an electric network depending on parameters of its elements for typical cases of connection of consumers on voltage of 10 KV is carried out. The obtained dependence allows us to talk about the possible use of normalized values to estimate network bandwidth. The method of measuring the electrical parameters of a three-phase network based on the approximation of the input signal by the sum of harmonic components has been further developed. Features of the method are automatic adjustment of the frequency and duration of the observation interval in a given range, the use of a complete set of phase voltages (or linear) in determining the frequency taking into account their weight values, which reduces measurement errors in difficult conditions - in the presence of asymmetry, higher harmonics, aperiodic component or in the absence of voltage in a separate phase. In addition, the measurement method uses a constant quantization frequency of the input digital data, which simplifies the hardware of the device. A method of calculating the current values with a precise reference to the voltage period obtained by the previous method is proposed, which eliminates the frequency error in the measurement regardless of the location of the beginning and end of the observation interval relative to the input digital signal. The system of the account of electric energy with use of indicators of quality of electric energy and efficiency of electric consumption is offered. A feature of the system is the additional accounting of losses for the transmission of electricity by comparing the characteristics of electricity consumption of the current consumer with those for the reference consumer, ie the use of loss factors or power. This method of accounting allows you to correctly rate all deviations in the modes of load, such as reactivity, nonlinearity and nonstationarity. A system of penalties for deterioration of electricity quality is proposed, based on the calculation of "penalty" energy if the consumer violates the norms of electricity consumption and "non-tariffed" energy, if there are no violations by the consumer, but the quality of electricity does not meet the norms. The basics of billing on the basis of this electricity metering system are proposed. In the fifth section, the data confirming the theoretical provisions of sections 3 and 4 were experimentally obtained. In particular, estimates of the quality of electricity consumption were implemented by comparison with a set of reference consumers. The experiment showed the possibility of successful application of Frieze current generation and its subsequent analysis to assess the quality of electricity consumption. At the same time parallel use of its three-phase and single-phase implementations for an estimation of asymmetry, nonlinearity and reactivity accordingly is possible. The method of comparison with the reference average reactive consumer proposed in section 3 has not proved to be an effective tool of analysis and does not seem promising. At the same time, the separation of the harmonic components of the Frieze current in the direction of their active component allows you to effectively track the source of currents of higher harmonics. The above methods using the model of a fragment of the power system with different types of load confirmed the correctness of the developed methods for assessing the quality of electricity consumption. Tests using oscillograms obtained on real three-phase loads (traction substation) also confirmed the efficiency and effectiveness of the developed assessment methods. In models with exceeding the permissible modes, the use of the mathematical apparatus developed in Section 4 allowed to identify the source of distortion, even if several consumers act as sources of these distortions at the same time.

Об’єктом дослідження є електричні мережі ливарно-механічного заводу, а також методи та засоби підвищення енергоефективності асинхронних двигунів. Предметом дослідження є якість електроенергії в розподільних електричних мережах. Основною метою роботи є підвищення надійності електропостачання споживачів ливарно-механічного заводу шляхом модернізації основних складових частин системи електропостачання, а саме головної трансформаторної підстанції 110/10 кВ та цехових трансформаторних підстанцій 10/,4 кВ, чим усунуться наявні проблеми, на зразок недостатньої потужності силових трансформаторів. Для утримання показників якості електроенергії в межах існуючих норм проведено дослідження методів і засобів зниження рівня несиметрії та несинусоїдальності напруги шляхом впровадження додаткових технічних засобів. Досліджено ефективність впровадження таких технічних рішень з точки зору економічної ефективності. Розроблено заходи щодо безпечної роботи підстанцій заводу.
The object of research is the electrical network of casting-mechanical plant and methods and means of improving energy efficiency of induction motors. The subject of research is the quality of electricity in the distribution electrical networks. The main purpose of work is improve the reliability of power supply casting-mechanical plant by upgrading major system components power system of plant, namely the main transformer substations 110/10 kV and guild transformer substations 10/4 kV, which to remove existing problems, like insufficient capacity of power transformers. To keep the power quality parameters within the limits of existing rules performed research of methods and means of reducing the voltage unbalance and nonsinusoidality by implementing additional technical tools. Researched the efficiency of these technical solutions in terms of economic efficiency. Developed measures for the safe operation of the power substation of casting-mechanical plant.
ЗМІСТ ВСТУП 8 1 АНАЛІТИЧНА ЧАСТИНА 10 1.1 Коротка характеристика проектованого об'єкту 10 1.2 Причини відхилення показників якості електроенергії від нормованих 11 1.3 Кількісна оцінка показників якості електроенергії в цехових мережах промислових підприємств 16 1.4 Способи підвищення якості електроенергії в умовах промислових підприємств 20 2 НАУКОВО-ДОСЛІДНА ЧАСТИНА 27 2.1 Розрахунок електричних навантажень 27 2.1.1 Загальні відомості 27 2.1.2 Визначення розрахункового навантаження по цехах 28 2.2 Побудова картограми електричних навантажень, визначення їх центру і місцерозташування ГПП 29 2.3 Вибір силових трансформаторів 32 2.3.1 Загальні вимоги до силових трансформаторних підстанцій 32 2.3.2 Вибір числа і потужності силових трансформаторів ГПП 32 2.4 Вибір схеми електропостачання підприємства 34 2.4.1 Загальні стани 34 2.4.2 Вибір конструктивного виконання і схеми з'єднання ГПП 35 2.4.3 Розрахунок і вибір перерізу кабелів, що живлять головний розподільний пункт (ГРП) 36 2.5 Вибір схеми розподільної мережі підприємства 36 2.5.1 Вибір раціональної напруги розподільної мережі 36 2.5.2 Компенсація реактивної потужності у мережах напругою 10 кВ промислових підприємств 37 3 ТЕХНОЛОГІЧНА ЧАСТИНА 39 3.1 Вибір схеми електропостачання ТП і трасування КЛ 39 3.2 Розрахунок струмів к.з. в установках напругою вище 1 кВ 41 3.3 Розрахунок струмів КЗ в установках до 1 кВ 44 4 ПРОЕКТНО-КОНСТРУКТОРСЬКА ЧАСТИНА 49 4.1 Вибір обладнання на підстанції напругою 110/10 кВ 49 4.1.1 Вибір роз'єднувача 50 4.2 Розрахунок і вибір електричної мережі цеху механічної обробки 52 4.2.1 Вибір схеми цехової електричної мережі 52 4.2.2 Визначення розрахункових навантажень цеху 53 4.2.3 Визначення розрахункових струмів 55 4.2.4 Вибір типу кабелів і їх перерізів 55 4.2.5 Вибір комутаційно-захисних апаратів в системі електропостачання напругою до 1 кВ 57 4.2.6 Вибір розподільних шаф і пунктів 58 4.2.7 Вибір режиму нейтралі в цеху з урахуванням технологічних особливостей споживачів електроенергії 59 4.3 Розрахунок електроосвітлення цеху 60 4.4 Релейний захист і автоматика 62 4.4.1 Релейний захист силових трансформаторів типу ТДН-10000/110 62 4.4.2 Розрахунок диференціального струмового захисту 62 4.4.3 Газовий захист ТДН-10000/110-70У1 68 5 СПЕЦІАЛЬНА ЧАСТИНА 70 5.1 Аналіз результатів використання відомих засобів підвищення енергоефективності асинхронних двигунів 70 5.1.1 Активні фільтри і фільтро-компенсуючі пристрої 70 5.1.2 Послідовні фільтри 72 5.1.3 Паралельні фільтри 73 5.1.4. Комбіновані фільтри 77 5.2 Дослідження по вибору параметрів і ефективності застосування пропонованих засобів підвищення енергоефективності АД 79 6 ОБГРУНТУВАННЯ ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ 88 6.1 Загальні поняття про собівартість продукції 88 6.2 Класифікація витрат, що утворюють собівартість продукції 89 6.3 Розрахунок собівартості передачі і повної собівартості електроенергії проектованої лінії 90 7 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ 98 7.1 Вимоги до заземлюючих пристроїв електроустановок напругою вище 1 кВ з великими струмами замикання на землю 98 7.2 Розрахунок заземлюючого пристрою ГПП 110/10 кВ 100 7.3 Оцінка стійкості роботи об'єкту енергетики до дії вибуху 104 8 ЕКОЛОГІЯ 106 8.1 Актуальність охорони навколишнього середовища 106 8.2 Шумове забруднення довкілля та заходи його зменшення 107 ЗАГАЛЬНІ ВИСНОВКИ ДО ДИПЛОМНОЇ РОБОТИ 109 ПЕРЕЛІК ПОСИЛАНЬ 110

Este presente trabalho visa fornecer novas ferramentas para a análise de índices de qualidade no âmbito do planejamento agregado de investimentos em sistemas de distribuição primária. O planejamento agregado de investimentos representa uma metodologia de previsão de investimentos em Sistemas de Distribuição de uma empresa, que utiliza a análise estatística e classificação de rede em famílias para representação da rede, considera aspectos de incertezas e critérios de priorização de obras, em função dos recursos disponíveis, e informa o tipo de obra a ser realizada e o montante de investimentos necessário por tipo de obra. Este trabalho procura complementar o modelo através da análise técnica dos índices de qualidade, quantificando-se os benefícios obtidos ao longo do horizonte de estudo, através de um sistema computacional que, baseado nos resultados dos representantes dos grupos de redes, determina os índices técnicos para tais representantes, para as regionais definidas e para todo o sistema, possibilitando a análise gerencial da evolução da rede elétrica. Também foi desenvolvida ferramenta que permite a determinação do Custo Incremental Médio de Longo Prazo (CIMLP) e do Custo Marginal do sistema de média tensão, englobando subestações de distribuição e circuitos primários do sistema elétrico. O trabalho é finalizado com o estudo de um caso de planejamento de uma área de concessão de uma empresa fictícia, onde são executados os processamentos e analisados os resultados técnicos, de custos e de qualidade.
This work aims at developing new tools for the analysis of quality of supply indices regarding long term investment planning of primary electric power distribution systems. Investment planning in aggregated basis represents a established methodology for estimating future investments in all distribution systems of a utility, by using statistic and clustering analysis to represent the overall network through groups of elementary distribution systems. The methodology also considers uncertainty and makes use of a number of criteria to prioritize new facilities to be incorporated into the system, taking into account financial constraints. For each new facility the system determines costs and corresponding benefits. This dissertation complements such model through the introduction and analysis of various quality of supply indices, helping the planner engineer to assess all benefits related to a given investment plan. The developed computational system is based on the results obtained for each elementary distribution system. It then evaluates global and regional technical indices, that allows for important managerial analysis concerning the system expansion. The computational system also evaluates the average long range incremental and the marginal costs associated with a specific investment plan, thus taking into account new facilities concerning substations and network feeders. A case study considering a fictitious distribution company and its overall system illustrates the tools developed, showing all potential studies and decision making capabilities which were made available during this research work.

Сиченко, В. Г. Розвиток наукових основ підвищення електромагнітної сумісності підсистем електричної тяги постійного струму залізничного транспорту : авт. дис. д-ра т. н.: 05.22.09 / В. Г. Сиченко ; Дніпропетр. нац. ун-т залізн. трансп. ім. акад. В. Лазаряна. - Д., 2011.
UA: АНОТАЦІЯ Дисертаційну роботу присвячено вирішенню науково-технічної проблеми – підвищенню електромагнітної сумісності підсистем електричної тяги постійного струму в умовах впровадження швидкісного руху, що покращить техніко- економічні показники перевізного процесу, його енергоефективність та безпеку. В результаті еспериментальних досліджень розроблено математичні моделі завад, що дозволить точніше проектувати та моделювати пристрої енергетичних каналів тягового електропостачання постійного струму. Отримала подальший розвиток методологія активної фільтрації, що призводить до підвищення електромагнітної сумісності підсистем електричної тяги постійного струму як з суміжними пристроями залізничної інфраструктури, так і з лініями зовнішнього електропостачання при зменшенні габаритних розмірів та встановленої потужності застосовуваного обладнання. Очікуваний економічний ефект від впровадження запропонованих рішень перевищує 4 млн. грн. Отримані наукові результати дозволяють надати рекомендації щодо проектування нових енергоефективних електромагнітносумісних перетворювачів комбінованої ідеології для модернізації тягових підстанцій та силових активних фільтрів на підстанціях з застарілим обладнанням. RU: АННОТАЦИЯ Диссертационная работа посвящена решению актуальной научно- технической проблемы - повышению электромагнитной совместимости подсистем электрической тяги постоянного тока в условиях внедрения скоростного движения, которое улучшит технико-экономические показатели перевозочного процесса, его энергоэффективность и безопасность. Рассматривая ЭМС, как один из показателей качества функционирования системы тягового электроснабжения, необходимо охватывать весь комплекс технических средств, которые задействованы в процессе передачи и потребления электроэнергии и учитывать, что система тягового электроснабжения представляет собой сложную электродинамическую распределенную систему, которая характеризуется стохастическим характером изменения параметров функционирования. Эти параметры изменяются в пространстве, плоскости и времени, изменяя электромагнитную обстановку в комплексе система тягового электроснабжения-смежные устройства (линии внешнего энергоснабжения, автоблокировки и продольного электроснабжения, линии связи, информационные каналы передачи данных, каналы телеуправления и телесигнализации, рельсовые цепи). Основой этого влияния является распространение кондуктивних помех через разнообразные гальванические связи. В результате еспериментальних исследований установлено, что питающие напряжения 110 кВ и 35 кВ превышают предельно допустимые значения. Уровень напряжения на шинах 10 кВ, от которых питаются тяговые трансформаторы, также превышает номинальное значение, но на уровне, в основном, нормально допустимого значения отклонения. Несимметрия напряжения, как на шинах 110 кВ, так и на шинах 35-10 кВ, находится в допустимых пределах. Качество электроэнергии за показателем искажения синусоидальности напряжения на шинах 10 кВ тяговых подстанций с 6-пульсовыми выпрямителями не отвечает требованиям стандарта. Коефициент несимметрии напряжения по обратной последовательности в линиях автоблокировки (АБ) значительно более высокий (более чем в 3 раза) в сравнении с линиями продольного электроснабжения (ПЭ), что побуждает ставить вопрос необходимости симетрирования напряжений в линиях АБ. Коэффициент искажения синусоидальности напряжения в линии АБ на тяговой подстанции с 12- пульсовой схемой выпрямления значительно превышает предельно допустимое значение и почти вдвое выше за KU в линии ПЭ. При этом KU и на тяговой подстанции с 6-пульсовой схемой выпрямления выше по сравнению с линией ПЭ. То есть, существующая идеология питания линии АБ с применением двойной трансформации, выполняя задание ограничения токов короткого замыкания и гальванической развязки, в сущности резко ухудшает качество электрической энергии, которая формирует условия ухудшения электромагнитной совместимости. Исследованиями также установлено, что изменение нагрузки тяговой подстанции практически не осуществляет влияния на показатели качества электрической энергии системы внешнего электроснабжения. Режимы напряжения как в системе тягового электроснабжения, так и в системе внешнего электроснабжения определяются случайными факторами и имеют слабую статистическую связь между собой. Разработанные математические модели помех, позволят точнее проектировать и моделировать устройства энергетических каналов тягового электроснабжения постоянного тока. Отмечается, что энергетические каналы (ЭК) тягового электроснабжения должны обеспечивать надежность и бесперебойность питания, стойкость к непредсказуемым влияниям и высокую энергоэффективность. На современном этапе, кроме указанного, они должны быть электромагнитносовместимыми с окружающей средой на всех уровнях передачи, превращения и потребления электрической энергии. Указанные процессы обеспечиваются рядом разнообразных устройств, образовывающих, собственно, ЭК: линии электропередачи, трансформаторы, преобразователи, инфраструктура тяговой сети и потребители электрической энергии. Рассматриваются направления усовершенствования ЭК и возможные варианты их схемной реализации. Перспективными являются структуры децентрализованого питания и разработка систем питания с промежуточным звеном повышенной частоты. Основными устройствами энергетических каналов системы тягового электроснабжения являются тяговые преобразователи. Современный выпрямитель является сложным, многофункциональным устройством и выполняется на принципах комбинированной идеологии с расширенными функциями, в том числе осуществление функции активной фильтрации. В работе получила дальнейшее развитие методология активной фильтрации, которая приводит к повышению электромагнитной совместимости подсистем электрической тяги постоянного тока как со смежными устройствами железнодорожной инфраструктуры, так и с линиями внешнего электроснабжения при уменьшении габаритных размеров и установленной мощности применяемого оборудования. Ожидаемый экономический эффект от внедрения предложенных решений превышает 4 млн. грн. Полученные научные результаты позволяют предоставить рекомендации для проектирования новых энергоэффективных электромагнитносовместимых преобразователей комбинированной идеологии для модернизации тяговых подстанций и силовых активных фильтров на подстанциях с устаревшим оборудованием. EN: THE SUMMARY Thesis is dedicated to solve scientific and technical problems - improve electromagnetic compatibility of alternative current electric traction subsystems in a highspeed lines that will make possible to improve technical and economic characteristics of transportation process, its efficiency and security. On the basis of experimental studies the author developed mathematical models of disturbances, that will make possible to design and simulate devices of power traction DC supply systems in a more accurate way. The author developed the methodology of active filter, that leads to improve the electromagnetic compatibility of electric DC traction subsystems with adjoining devices of railway infrastructure and with external power supply systems reducing the overall dimensions and installed capacity of the applicable equipment. Expected economic effect of proposed approach exceeded 4 million grn. Proposed results can provide propositions about designing of new energy converters on the basis of combined ideology for modernization of traction substations and power active filters of substations with aging equipment.

Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.09.03 – електротехнічні комплекси та системи. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. Розглядаються методи оптимізації режимів систем електропостачання з несиметричними і нелінійними навантаженнями з метою підвищення енергетичних показників і розрахунку симетро-компенсуючих пристроїв. Обґрунтовано необхідність і можливість застосування комп'ютерних засобів, розроблено узагальнені алгоритми реалізації пошукової оптимізації. Розроблені методи успішно застосовані для оптимізації режимів в трипровідних і чотирипровідних системах, в тому числі в системах з взаємно-зв'язаними індуктивностями, в системах залізничного електропостачання, в системі з нейтралером, в системах живлення асинхронних двигунів, освітлювальних приладів високого тиску, в системах з силовими активними фільтрами, а також для випадків кількох навантажень з урахуванням вкладу кожного з них в зниження енергетичних показників системи.
Thesis for a Doctor’s degree in Engineering Science by specialty 05.09.03 – Electrical Engineering Complexes and Systems. – National Technical University "Kharkov Polytechnic Institute", Kharkiv, 2018. The dissertation is devoted to the development and research of optimization methods of power supply systems modes in electrotechnical systems with asymmetric and nonlinear loads in order to increase the energy indices and calculate the parameters of symmetry-compensating devices using mathematical and computer models, and using search engine optimization implemented with the use of modern software of computer mathematics. The necessity and the possibility of using computer tools for solving set tasks are substantiated. The generalized algorithms for implementing search engine optimization using modern software packages are developed. The possibilities of applying different optimization criteria for solving the problems of increasing the energy indices of power supply systems with asymmetric and nonlinear loads are shown. The properties of the search engine optimization system have been found to extrude the inappropriate element of the synthesized device, as well as the possibility of releasing the optimization variables by increasing their amount, which allows us to get ahead of a faster locating of the local minimum and then recalculate the parameters corresponding to the global minimum are shown. The developed method of search optimization using the models of power supply systems has been successfully applied for optimization of regimes and synthesis of symmetry-compensating devices in three-phase three-wire and four-wire systems of power supply. The possibilities of using the optimization tools for Mathcad and Matlab software packages are considered, in particular, using zero-order methods that do not require the calculation of derivatives, such as the deformed polyhedron method and the conjugate gradient method. The algorithm of load equivalence is proposed, with the help of which the symmetrical and asymmetric parts of the load are allocated. After this, the parameters of the balancing device are determined with sufficient accuracy by means of the Steinmetz and Kennely formulas. The method of currents direct symmetric component rotation with the preservation of symmetry and the mode of full reactive power compensation is proposed. For four-wire systems, the use of a generalized reactive element in a symmetry-compensating device is proposed, which accelerates the process of achieving the optimal solution. The method of determining the optimal mode based on the decomposition of the power supply system, which improves the convergence of the solution processes, is developed. Systems of power supply containing inductively coupled elements are considered. The calculation of the symmetry-compensating device of the traction system of the alternating current railway power supply is considered. A four-wire system with a neutralizer was studied, with the help of search engine optimization the parameters of the symmetry-compensating device were determined which allows to balance and counterbalance such a system. The possibilities of optimization of the regime in the power system of asynchronous motors, including the asymmetry of the supply network, are shown. Compensation of reactive power allows here to reduce the consumed currents and increase the efficiency of the system. To find the optimal modes of systems with an arc discharge, visual models have been developed that are adapted for use with the SimPowerSystem library elements. With the help of these models, the possibilities of increasing the power indices of arc discharge power supply systems, including high-pressure lighting devices, are investigated. It was shown that the optimization of the power factor alone, calculated with the help of the pro-posed methods, leads to decrease in the current consumed by the fundamental harmonic, which substantially reduces the losses in the transmission lines. For a thyristor compensator with single-stage switching, the advantage of symmetric control is proven, which greatly improves the spectrum of harmonics of supply currents. The use of the search optimization method to increase the power factor is shown without the use of traditional rather complicated control systems by power active filters. Comparison signals are used as control signals, synchronized with the phase voltages of the supply system. The amplitudes of these signals are accepted as optimization variables, and the optimization criterion is determined by the balance of active power in the system, which is characterized by the stabilization of the periodic voltage on the storage capacitor of the power active filter. The problems of synthesis of symmetric-compensating devices for several asymmet-rical loads in parallel and cascade connection are considered. The task is to determine the parameters of the symmetric-compensating devices for each of the loads separately, and the contribution to the creation of asymmetry and the generation of reactive power of each connected load must be taken into account. This problem is solved by the method of search optimization, and it is shown that, in forming the objective function, currents in the feeders, supplying energy from the point of connection of the load to the network to the common point of connection of the load and the symmetric-compensating device. It is effective to use the developed decomposition method, which makes it possible to simplify and accelerate the determination of the optimal regime of the system under study, taking into account the contribution of each load to the reduction of the energy parameters of the system as a whole. The case is also analyzed when two loads consisting of both unbalanced linear and nonlinear loads are simultaneously connected to the network. Optimization of the regime with increasing power factor is achieved by using a parallel power active filter with control over the proposed optimization algorithm. Methods and algorithms of search optimization developed for the purposes of increasing the energy indicators of power supply systems with asymmetric and nonlinear consumers developed and presented in the thesis work are characterized by high accuracy, the maximum possible use of computer technology, low computer time and the possibility of complete automation of design and research procedures in solving theoretical and practical tasks related to increasing energy performance and quality of electrical energy in power supply systems.

Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.09.03 – електротехнічні комплекси та системи. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. Розглядаються методи оптимізації режимів систем електропостачання з несиметричними і нелінійними навантаженнями з метою підвищення енергетичних показників і розрахунку симетро-компенсуючих пристроїв. Обґрунтовано необхідність і можливість застосування комп'ютерних засобів, розроблено узагальнені алгоритми реалізації пошукової оптимізації. Розроблені методи успішно застосовані для оптимізації режимів в трипровідних і чотирипровідних системах, в тому числі в системах з взаємно-зв'язаними індуктивностями, в системах залізничного електропостачання, в системі з нейтралером, в системах живлення асинхронних двигунів, освітлювальних приладів високого тиску, в системах з силовими активними фільтрами, а також для випадків кількох навантажень з урахуванням вкладу кожного з них в зниження енергетичних показників системи.
Thesis for a Doctor’s degree in Engineering Science by specialty 05.09.03 – Electrical Engineering Complexes and Systems. – National Technical University "Kharkov Polytechnic Institute", Kharkiv, 2018. The dissertation is devoted to the development and research of optimization methods of power supply systems modes in electrotechnical systems with asymmetric and nonlinear loads in order to increase the energy indices and calculate the parameters of symmetry-compensating devices using mathematical and computer models, and using search engine optimization implemented with the use of modern software of computer mathematics. The necessity and the possibility of using computer tools for solving set tasks are substantiated. The generalized algorithms for implementing search engine optimization using modern software packages are developed. The possibilities of applying different optimization criteria for solving the problems of increasing the energy indices of power supply systems with asymmetric and nonlinear loads are shown. The properties of the search engine optimization system have been found to extrude the inappropriate element of the synthesized device, as well as the possibility of releasing the optimization variables by increasing their amount, which allows us to get ahead of a faster locating of the local minimum and then recalculate the parameters corresponding to the global minimum are shown. The developed method of search optimization using the models of power supply systems has been successfully applied for optimization of regimes and synthesis of symmetry-compensating devices in three-phase three-wire and four-wire systems of power supply. The possibilities of using the optimization tools for Mathcad and Matlab software packages are considered, in particular, using zero-order methods that do not require the calculation of derivatives, such as the deformed polyhedron method and the conjugate gradient method. The algorithm of load equivalence is proposed, with the help of which the symmetrical and asymmetric parts of the load are allocated. After this, the parameters of the balancing device are determined with sufficient accuracy by means of the Steinmetz and Kennely formulas. The method of currents direct symmetric component rotation with the preservation of symmetry and the mode of full reactive power compensation is proposed. For four-wire systems, the use of a generalized reactive element in a symmetry-compensating device is proposed, which accelerates the process of achieving the optimal solution. The method of determining the optimal mode based on the decomposition of the power supply system, which improves the convergence of the solution processes, is developed. Systems of power supply containing inductively coupled elements are considered. The calculation of the symmetry-compensating device of the traction system of the alternating current railway power supply is considered. A four-wire system with a neutralizer was studied, with the help of search engine optimization the parameters of the symmetry-compensating device were determined which allows to balance and counterbalance such a system. The possibilities of optimization of the regime in the power system of asynchronous motors, including the asymmetry of the supply network, are shown. Compensation of reactive power allows here to reduce the consumed currents and increase the efficiency of the system. To find the optimal modes of systems with an arc discharge, visual models have been developed that are adapted for use with the SimPowerSystem library elements. With the help of these models, the possibilities of increasing the power indices of arc discharge power supply systems, including high-pressure lighting devices, are investigated. It was shown that the optimization of the power factor alone, calculated with the help of the pro-posed methods, leads to decrease in the current consumed by the fundamental harmonic, which substantially reduces the losses in the transmission lines. For a thyristor compensator with single-stage switching, the advantage of symmetric control is proven, which greatly improves the spectrum of harmonics of supply currents. The use of the search optimization method to increase the power factor is shown without the use of traditional rather complicated control systems by power active filters. Comparison signals are used as control signals, synchronized with the phase voltages of the supply system. The amplitudes of these signals are accepted as optimization variables, and the optimization criterion is determined by the balance of active power in the system, which is characterized by the stabilization of the periodic voltage on the storage capacitor of the power active filter. The problems of synthesis of symmetric-compensating devices for several asymmet-rical loads in parallel and cascade connection are considered. The task is to determine the parameters of the symmetric-compensating devices for each of the loads separately, and the contribution to the creation of asymmetry and the generation of reactive power of each connected load must be taken into account. This problem is solved by the method of search optimization, and it is shown that, in forming the objective function, currents in the feeders, supplying energy from the point of connection of the load to the network to the common point of connection of the load and the symmetric-compensating device. It is effective to use the developed decomposition method, which makes it possible to simplify and accelerate the determination of the optimal regime of the system under study, taking into account the contribution of each load to the reduction of the energy parameters of the system as a whole. The case is also analyzed when two loads consisting of both unbalanced linear and nonlinear loads are simultaneously connected to the network. Optimization of the regime with increasing power factor is achieved by using a parallel power active filter with control over the proposed optimization algorithm. Methods and algorithms of search optimization developed for the purposes of increasing the energy indicators of power supply systems with asymmetric and nonlinear consumers developed and presented in the thesis work are characterized by high accuracy, the maximum possible use of computer technology, low computer time and the possibility of complete automation of design and research procedures in solving theoretical and practical tasks related to increasing energy performance and quality of electrical energy in power supply systems.

У дисертаційній роботі здійснено комплексний аналіз особливостей функціонування ЛСЕП з врахуванням сучасних вимог концепції Smart Grid та виконано співставний аналіз методів оцінки обмінних процесів у ЛСЕП з джерелами РГ. На основі експертного аналізу виділено основні проблеми роботи ЛСЕП у вітчизняних системах електропостачання та енергозабезпечення. Розширено відому систему ПЯЕ для адекватного оцінювання рівнів ЕМС в ЛСЕП з дотриманням вимог концепції Smart Grid та оцінювання рівнів перетоків енергії на основі відомих показників. Розроблено та апробовано спеціалізований програмний модуль та нормативно-методичне забезпечення розширеного енергетичного аудиту з використанням обмінної потужності, яке дає змогу: визначити обмінну потужність та частку взаємного впливу в довільному перетині ЛСЕП з врахуванням особливостей їх конфігурації, режимів роботи окремих елементів та ЛСЕП в цілому; отримати інформацію про обмінні процеси в ЛСЕП з різним рівнем інформаційного забезпечення; адекватно враховувати особливості протікання режимів у ЛЕС, зокрема, двонаправленість потоків електроенергії та визначити реальний їх розподіл в елементах ЛСЕП.
In the dissertation the complex analysis of the peculiarities of functioning of local power supply systems (LPSS) is carried out taking into account the modern requirements of the Smart Grid concept and the comparative analysis of methods of estimation of exchange processes in LPSS with dispersed energy sources is performed. The need to extend the known LPSS system to adequately assess the EMC levels in the LPSS with the requirements of the Smart Grid concept and to estimate the energy flow rates using known indicators is justified. The analysis of exchange processes of LPSS under the influence of different types of impulse disturbances and sources of non-sinusoidal voltage and current caused by the peculiarities of modes of operation of both individual elements and the system as a whole for single and three-phase cross sections of LPSS is carried out. New relationships were obtained to evaluate the effect of non-sinusoidality and to take into account the ripple coefficients on the nature of the exchange processes. The analysis of the exchange processes in LPSS has been carried out taking into account the real characteristics of the elements with electromagnetic bonds (transformers, reactors, transmission lines, etc.) and new relationships have been obtained, which link the exchange power and the coefficients of magnetic coupling for one and three-phase LPSS operating in both sinusoidal and non-sinusoidal modes, as well as in symmetric and asymmetric modes. Regulatory and methodological support of the expanded energy audit with the use of exchange power was developed and tested. Regulatory and methodological support was used: for conducting an expanded energy audit at the enterprise of СE «Vasylkiv Leather Company» (Vasylkiv, Kyiv region); analysis of parallel operation of standby power supply systems both separately and in combination with the network used for powering server equipment of PLC «Prostonet»; was the basis for the course of lectures on discipline "Electrical Engineering Complexes", which will be taught in 2019 at Vasylkivsky College of NAU. A specialized software module and regulatory and methodological support for the extended energy audit using exchange power have been developed and tested. The proposed regulatory and methodological support makes it possible to: determine the exchange power and the proportion of mutual influence in an arbitrary intersection of LPSS, taking into account the peculiarities of their configuration, modes of operation of individual elements and LPSS as a whole; to obtain information on exchange processes in the LPSS with different levels of information support; to adequately take into account the peculiarities of the flow of modes in the LPSS, in particular, the bidirectionality of electricity flows and to determine their real distribution in the elements of LPSS.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.14.02 – електричні станції, мережі і системи. Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. Дисертація присвячена розвитку методів визначення часткової участі суб'єктів розподілу і споживання електричної енергії (ЕЕ) в відповідальності за порушення якості електроенергії (ЯЕ) шляхом їх доповнення методами, які можна використовувати в локальних засобах обліку, а також розробці методу визначення часткової участі суб'єктів за показниками коливання напруги (КН). Аналіз методів детермінованого визначення часткової участі суб'єктів в відповідальності за порушення ЯЕ показав, що існують розроблені методи і методики по: симетрії напруги, синусоїдальності кривої напруги, сталому відхиленню напруги. У той же час відомі розробки в повному обсязі не вирішують завдання експлуатації електричних мереж і не охоплюють всі показники якості електроенергії (ПЯЕ), властиві тривалим відхиленням характеристик напруги від номінальних значень. Потрібно вирішити завдання побудови локального пристрою для визначення часткової участі споживачів у спотворенні симетрії, а також розробити методику визначенням відповідальності суб'єктів за порушення вимог до ЯЕ за показниками КН. Розроблено метод визначення місця розташування джерела КН в системі електропостачання. Отримав розвиток метод аналізу кривої напруги стосовно дискретної обробки інформації. Метод дозволяє виявляти й оцінювати локальні екстремуми, виділяти області монотонної зміни і незмінності кривої напруги. Отримав розвиток метод визначення відповідальності споживача і постачальника за спотворення симетрії напруги, заснований на розрахунку балансу ЕЕ по якій потрібно визначення відповідальності споживача за період моніторингу. Розроблено методики аналізу кривої зміни напруги, визначення місця знаходження джерела та часткової участі споживача у відповідальності за перевищення допустимого рівня КН, визначення часткової участі суб'єктів в порушенні симетрії локальної системи обліку споживання та контролю ЯЕ, комплексна методика визначення часткової участі споживача в відповідальності за порушення ПЯЕ.
The thesis is for obtaining scientific degree candidate of technical sciences in specialty 05.14.02 – Electrical power stations, networks and systems. National Technical University "Kharkov Polytechnic Institute", Kharkov, 2018. Analysis of the methods of deterministic determination of the partial participation of subjects in the responsibility for violating the quality of electricity showed that there are developed methods and techniques for: voltage symmetry, sinusoidal voltage curve, constant voltage deviation. At the same time, known developments do not completely solve the problems of operation of electric networks and do not cover all the indicators of electricity quality, characterized by a long deviation of voltage characteristics from nominal values. It is necessary to solve the problem of constructing a local device to determine the partial participation of consumers in the distortion of symmetry, as well as develop a method of definition responsibility of subjects for violating the requirements for the quality of electricity in terms of voltage fluctuations. The method of determining the location of the source of voltage fluctuations in the power supply system is developed. Received the method of analysis of the voltage curve in relation to discrete processing of information. The method allows to detect and evaluate local extrema, to allocate areas of monotone change and invariance of the voltage curve. Developed a method for determining the responsibility of the consumer and supplier for the distortion of voltage symmetry, based on the calculation of the balance of electricity, which requires the definition of customer responsibility in the monitoring period. The methods of analysis of the voltage curve analysis, the determination of the location of the source and the partial involvement of the consumer in the responsibility for exceeding the permissible level of voltage fluctuations, the determination of the partial participation of the subjects in violation of the symmetry of the local system of consumption accounting and electricity quality control, a comprehensive method for determining the partial involvement of the consumer in liability for violating the quality of electricity.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.14.02 – електричні станції, мережі і системи. Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. Дисертація присвячена розвитку методів визначення часткової участі суб'єктів розподілу і споживання електричної енергії (ЕЕ) в відповідальності за порушення якості електроенергії (ЯЕ) шляхом їх доповнення методами, які можна використовувати в локальних засобах обліку, а також розробці методу визначення часткової участі суб'єктів за показниками коливання напруги (КН). Аналіз методів детермінованого визначення часткової участі суб'єктів в відповідальності за порушення ЯЕ показав, що існують розроблені методи і методики по: симетрії напруги, синусоїдальності кривої напруги, сталому відхиленню напруги. У той же час відомі розробки в повному обсязі не вирішують завдання експлуатації електричних мереж і не охоплюють всі показники якості електроенергії (ПЯЕ), властиві тривалим відхиленням характеристик напруги від номінальних значень. Потрібно вирішити завдання побудови локального пристрою для визначення часткової участі споживачів у спотворенні симетрії, а також розробити методику визначенням відповідальності суб'єктів за порушення вимог до ЯЕ за показниками КН. Розроблено метод визначення місця розташування джерела КН в системі електропостачання. Отримав розвиток метод аналізу кривої напруги стосовно дискретної обробки інформації. Метод дозволяє виявляти й оцінювати локальні екстремуми, виділяти області монотонної зміни і незмінності кривої напруги. Отримав розвиток метод визначення відповідальності споживача і постачальника за спотворення симетрії напруги, заснований на розрахунку балансу ЕЕ по якій потрібно визначення відповідальності споживача за період моніторингу. Розроблено методики аналізу кривої зміни напруги, визначення місця знаходження джерела та часткової участі споживача у відповідальності за перевищення допустимого рівня КН, визначення часткової участі суб'єктів в порушенні симетрії локальної системи обліку споживання та контролю ЯЕ, комплексна методика визначення часткової участі споживача в відповідальності за порушення ПЯЕ.
The thesis is for obtaining scientific degree candidate of technical sciences in specialty 05.14.02 – Electrical power stations, networks and systems. National Technical University "Kharkov Polytechnic Institute", Kharkov, 2018. Analysis of the methods of deterministic determination of the partial participation of subjects in the responsibility for violating the quality of electricity showed that there are developed methods and techniques for: voltage symmetry, sinusoidal voltage curve, constant voltage deviation. At the same time, known developments do not completely solve the problems of operation of electric networks and do not cover all the indicators of electricity quality, characterized by a long deviation of voltage characteristics from nominal values. It is necessary to solve the problem of constructing a local device to determine the partial participation of consumers in the distortion of symmetry, as well as develop a method of definition responsibility of subjects for violating the requirements for the quality of electricity in terms of voltage fluctuations. The method of determining the location of the source of voltage fluctuations in the power supply system is developed. Received the method of analysis of the voltage curve in relation to discrete processing of information. The method allows to detect and evaluate local extrema, to allocate areas of monotone change and invariance of the voltage curve. Developed a method for determining the responsibility of the consumer and supplier for the distortion of voltage symmetry, based on the calculation of the balance of electricity, which requires the definition of customer responsibility in the monitoring period. The methods of analysis of the voltage curve analysis, the determination of the location of the source and the partial involvement of the consumer in the responsibility for exceeding the permissible level of voltage fluctuations, the determination of the partial participation of the subjects in violation of the symmetry of the local system of consumption accounting and electricity quality control, a comprehensive method for determining the partial involvement of the consumer in liability for violating the quality of electricity.

This master thesis deals with the proactive diagnostics and monitoring of state of the three phase asynchronnous motors in industrial company Bosch Diesel Jihlava. In master thesis is designed diagnostics system based on the selected suitable diagnostics methods and other appropriate process monitors the status of these technical equipments.

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No Brasil, até pouco tempo atrás, a qualidade da energia elétrica estava relacionada, basicamente, com interrupções do fornecimento de energia e a certas cargas especiais da indústria. Porém, nos últimos anos, sob a direção da agência reguladora do setor, a ANEEL (Agência Nacional de Energia Elétrica), juntamente com especialistas, a área de qualidade da energia elétrica passou a receber uma atenção significativa, sendo legislada e adquirindo suas regulamentações iniciais. A área de Qualidade da Energia Elétrica passou, então, a formalmente existir e abranger um conjunto maior de fenômenos e eventos da rede elétrica. Em função dessa recente regulamentação, este trabalho apresenta o projeto de um medidor da qualidade da energia elétrica. Um dos focos do medidor é ser de baixo custo, tornando-o viável para o uso em grande escala. Este medidor é um sistema eletrônico que processa digitalmente os sinais de tensão da rede elétrica, extraindo os dados relacionados à qualidade da energia elétrica; tais dados são armazenados localmente e, posteriormente, acessados remotamente e enviados para um banco de dados, de forma que possam ser analisados.
Some years ago in Brazil the power quality was related, basically, with interruption of supplied energy and certain special loads of industry. In recent years, however, under controls of the regulating agency ANEEL (Agência Nacional de Energia Elétrica) and with specialists, the power quality area received the due attention and was legislated and acquired regulations. So, finally, the area of Power Quality was formally created and now it embraces several electrical phenomena and events. Because of the new regulations, this work presents a project of a power quality meter. One of meter s focuses is to be a low cost system and becomes able to be used in large scale. This power quality meter is an electronic system that processes the voltage signal of electrical network and extracts data related to power quality; the data are locally stored and after they are remotely accessed and transmitted to a data base to be analyzed.

Thèse (M.Eng.) -- Université du Québec à Chicoutimi, 2007.
La p. de t. porte en outre: Mémoire présenté comme exigence partielle de la maîtrise en ingénierie. CaQCU Bibliogr.: f. [121]-124. Document électronique également accessible en format PDF. CaQCU

碩士
國立中央大學
電機工程學系
103
This thesis is to describe the design process and methods of a programmable power-quality power supply. The main purpose is to design an AC power supply, but it can editing an arbitrary output voltage waveform through a programmable program not only the general common sinusoidal output voltage waveform. The alternating current with arbitrary waveform can be used to emulate a power supply of pollution with power harmonics, flicker, sags, swells and other disturbances. They can be used as a reference simulate power source when we are designing a power source filter or can be used to test equipment for power pollution interference. Power-quality power supply rated output power given here is 500 VA, which is mainly use of class-D power amplifier as the main body. The stage before class-D power amplifier is a boost circuit which used to rise the input voltage. Input voltage of the class-D power amplifier is output voltage of the boost circuit. Programmable signal and user interface are edited by the LabVIEW software, and the signal DAC output through myDAQ which input to the microcontroller dsPIC30f4011 for the PWM control of switching elements in the system. Finally, coupled with hardware circuits, software and firmware to complete the overall structure and function. Sine wave output voltage of the system up to R.M.S. value 120V. In the part of harmonic waveform output voltage can be added multiple sets of arbitrary frequency, amplitude harmonic components. The highest harmonic frequency up to 2kHz. In the part of flicker output voltage waveform can be added multiple sets of arbitrary frequency, amplitude flicker component. The minimum flicker frequency up to 1Hz. In the part of swells, sags, interrupts waveform output voltage can be set that voltage fluctuation occur at any times, and can do multiple sets of voltage fluctuation function.

Kitron had wishes to be able to test and measure how disturbance affects their vehicle electronic units before they have been verified by SP Technical Research Institute of Sweden in Borås. This work started with the writing of a demand specification together with Kitron for a product PSQS, Power Supply Quality Simulator, which can generate some test pulses according to a standard for electronic units to Volvos vehicles. A design proposal was developed with the help the demand specification and was verified with the help of simulations. All electric schematics was designed with the guide of the design proposal. The pulses realized in the works of this thesis are those which Kitron experienced that they have a need to test in their own premises and which are possible to generate with the means available. All work took place at Kitron in Jönköping, the restriction of the work has been the cost of components not to be to high as well as the finished product shall be easily managed. This thesis work resulted in a unit which is possible to produce a number of disturbances on the voltage feed to a unit under test. Some pulses have not been completely correct according to Volvos standard. There are large possibilities to further develop PSQS to a unit that follows Volvos standard and even other vehicle producer’s standards.

The distortions of input voltage and current waveforms generated by switch mode power supply (SMPS) operation are a major cause of concern in the power quality performance of commercial office buildings. These distortions are usually evaluated by performing a site survey of the building. In this thesis, a power quality simulator is proposed as an alternative method to site surveys in evaluating the power quality characteristics of such nonlinear loads in a commercial environment. The power quality simulator is built around the assumption that the total load kVA on each phase of the three-phase four-wire distribution system can be approximated. The proposed simulator is tested on two commercial office buildings, namely the Owen Hall and Dearborn Hall buildings of Oregon State University. Experimental time-domain and frequency-domain waveforms are presented. These are compared with the simulation results to prove the viability of the power quality simulator in determining the power quality characteristics of the building. Finally, a passive filtering technique was simulated to reduce the harmonic distortions in voltages and currents to further demonstrate the potential uses of the power quality simulator.
Graduation date: 2000

The extensive use of nonlinear loads in today’s world has inspired considerable research interest in the area of power quality improvement. This thesis proposes an integrated magnetics based compact solution which provides regulated, balanced and sinusoidal load voltage drawing sinusoidal and balanced currents from the grid. Thus, it supplies clean power to the load without polluting the grid. It consists of an EI shaped magnetic core and two compensators known as the series and shunt compensators. The series compensator ensures the quality of output voltage, where as the shunt one takes care of quality of the current drawn from the grid. The magnetic circuit acts as a common domain for interaction between the energy ports. It also provides galvanic isolation between the inverters, load and the grid. The magnetic circuit incorporates a virtual arm switching mechanism to have an option of connecting the inverters either in series or in parallel with each other depending on the requirements. During normal mode when the switch remains inactive, the series inverter is effectively in series with the load and the shunt inverter is effectively connected across the load. Therefore, the voltage source inverters can be independently controlled to serve the purpose of series and shunt compensation. The shunt inverter is always connected in shunt with the grid. The magnetic arm switch is activated during grid power failure. Then the switch ensures parallel connection of the inverters and the load. The inverters are controlled to share the load power according to the respective ratings. Thus the magnetic arm switching mechanism helps in improving the system reliability. The series inverter also can be connected in parallel with the shunt one in presence of the grid to supplement the shunt inverter by supplying harmonic and reactive currents. The design, modelling and implementation issues for single phase applications are considered first. A simple controller structure for this application is also discussed in the thesis. The individual compensation actions are then verified by simulation and experimental results. The three phase power quality compensator is in principle an extension of the single phase quality power supply. It is realized by combining three single phase units with minor modification in terms of windings. A more compact structure is also proposed wherein a single integrated magnetic circuit for the three phase application can be used. The composite magnetic circuit is modelled and designed considering a laboratory prototype. A synchronously rotating reference frame based controller structure for the series and shunt compensators are discussed. The control of the inverters in power sharing mode (with parallel connected inverters) are also proposed and discussed. Experimental and simulated results are presented to verify and validate the operation of this compensator in different operating modes. An effective improvement in the control dynamics is achieved for handling unbalanced and nonlinear loading without increasing inverter switching frequency and controller parameters. In other words, the modified control scheme can handle nonlinear and unbalanced loading with relatively slow proportional integral (PI) controllers. Suitable feed forward compensation terms corresponding to each harmonic component are added to the output of the PI controllers in order to achieve this effective improvement. Experimental results show good improvement in this regard (for both series and shunt compensations).

A dissertation submitted in partial fulfillment of the Master's Diploma in Technology: Electrical Engineering (Heavy Current), M.L. Sultan Technikon, 1998.
With the ever increasing electrical demand on an electrical system, the quality of the supply will be tested more and more. And it is with this deteriorating quality that the topic of voltage dips and depressions has become a contentious issue amounts the industrial sector and supply authorities, hence the means to combat this issue in recent years.
M

碩士
聖約翰科技大學
工業工程與管理系碩士在職專班
101
Switching power supply is the major driver of consumer electronic products. Electronic products cannot be operated safely without stable quality of switching power supply. It focuses on examining reliability and failure status at design stage of switching power supply in order to correcting design problem before official manufacture. It can improve product quality and become key advantage for manufacturer. This study will be emphasized on collecting, clarifying and resulting problems on products design stage. Furthermore, it will conclude an effective failure data resource to offering potential failure models of new products development. It could assist to find product design problems as data collecting. The fail chances will be decreased, if the problems were found in early stage. Switching power supply development will process to design failure mode effects analysis and design quality review to ensure products quality. This research use database and failure report analysis corrective action system the concept, it can collect failure problems in products design quality review, and establish failure database with potential failure models. Those models could apply on design failure mode effects analysis, and use risk priority score to ensure quality enhancing. This study concluded, there are too many varieties of switching power supply. It has to be classified into different product categories, and set up circuit block. After that, failure modes and effects analysis can be applied to achieve best result. This information can find potential failure modes effectively. Those models could apply on design failure mode effects analysis. Consequently, Classification to switching power supply modes and circuit block. Set up with key components and failure model databases can find high risk potential failure model more easily.

M. Ing.
This research study aims at presenting the management of quality problem issues that often result from procured items in a power plant. The motivation for carrying out this research was an unacceptable risk of undesirable impact on plant availability, or operating costs that arises from quality problem issues of procured items in a particular power plant. In this dissertation, the author aims to provide an overview of quality management and procurement management, by focusing on how purchasing and supplier quality management (PSQM) can be integrated into power plants in order to effectively manage quality problem issues. A case study of the particular South African power plant (called ABC Power Plant as a pseudonym for the sake of confidentiality) was done.

碩士
中原大學
電機工程研究所
100
Abstract Due to the lack of fossil fuel and the greenhouse effect, the concerns about energy conservation and carbon emission reduction become main causes for a worldwide research and product applications. This thesis mainly focuses the operating characteristics of an electronic research and development building which has renewable sources. We considered “Connection Rule for the Renewable Energy Generation” of Taipower. There are a number of research reports. Most of them explore these rules, such as voltage changes, connected capacity, fault current, reversed power, and these steady-state operation analysis are the important items of early stage development. This thesis uses Paladin® DesignBase™4.0 simulation software to build the electricity distribution system of electronic research and development building, and uses the renewable energy module to analyze the operation of the electricity distribution system and three-phase short circuit faults at all buses. We also measure the harmonic voltage and current as the simulation parameters set by the simulation software. The results are in compliance with the harmonic standard. This study can be used as a reference of the application of power distribution system with distributed renewable energies connected to the utility.

University of Technology, Sydney. Faculty of Business.
NO FULL TEXT AVAILABLE. Access is restricted indefinitely. The hardcopy may be available for consultation at the UTS Library.
NO FULL TEXT AVAILABLE. Access is restricted indefinitely.

碩士
亞洲大學
經營管理學系碩士在職專班
99
In many countries, electric utilities are state-owned enterprises, the purpose of public investment in the provision of basic of public services to support economic development. Taiwan Power Company is a state-owned enterprises. State-owned enterprises is easy to form a market monopoly. State-owned enterprises pay less attention to the quality of power supply services. In recent years the power industry liberalization and internationalization, Taiwan Power Company is facing unprecedented competition. Market competition prompted the company must be committed to improve the quality of power supply services. The most important indicator of quality of power supply services is power supply reliability, power supply quantity and customer satisfaction. In this study, it is a case study of TPC Taichung Power Supply Branch. In recent years, this Branch has established computer monitor, to prevent lightning overhead lines, to prevent dug underground cables, to prevent the bird to touch electrical equipment, infrared measuring equipment, replacement of traditional relay to digital relay etc. These innovative methods, which can improve the quality of power supply services. How innovative methods to affect the quality of power supply services？ What is the relationship between innovative methods and quality of power supply services？ It is worth further study and research. In order to achieve the purpose, we must set the theme and scope of research. We must collection of topic-related research and literature. We need to understand the world of scholars and experts on the power supply reliability, innovative method and customer satisfaction related research. Proposed research framework and research methods. Interviews with the charge of technology and management of the unit. After collection the innovative methods, We have to design a questionnaire. Complete the questionnaires by the employees of this unit. Recovered questionnaires, using SPSS software for statistical analysis. To evaluate the relationship between power supply reliability, innovative method and customer satisfaction. After analysis, the researchers made the following conclusions: (1) Innovative methods to enhance power supply reliability has a significant impact, maintenance innovation to increase power supply has a significant impact; (2) Equipment innovation, operations innovation, has no significant effect on the increase in power supply; (3) Innovative methods, power supply reliability, quantity of power supply, to improve customer satisfaction, no significant effect; (4) To enhance supply reliability for the power supply, no significant effect. At the same time, the researcher made two recommendations as a reference to the company leaders and researchers.

碩士
國立交通大學
交通運輸研究所
99
This work presents an analytical model to investigate the effect of third party (e.g., government and green organizations) strategic intervention on green channel performance of a producer-retailer bidirectional distribution channel via the mediating effects of channel power reorientation and relationship quality management. Therein, the retailer is allocated with additional responsibility to collect used products for the producer for recycling and repairing. The proposed model is empirically tested using questionnaire survey data sampled from the producer-retailer distribution channels of consuming electronic product manufacturing industries. The results reveal that take-back legislation has significant effect on the retailer’s expectation of increase in bargaining power, leading to the increase in the retailer’s countervailing power. The utilization of relational investment strategies through relationship commitment as the key mediator determines permits not only alleviating the retailer’s countervailing power but also enhancing the bidirectional distribution channel performance. Relative to the bargaining power shift effect, relational investment strategies, appear to be more effective in promoting channel relationship commitment, thus leading to superior bidirectional channel performance.

碩士
國立臺北科技大學
電機工程系所
93
The system dynamic performance is a key factor that needs to be taken into account when designing an overhead catenary system for railway electrification .The dynamics performance considers the manner in which the contact system will oscillate when disturbed by the movement of the pantograph and the effect this has on the current collection process. High voltage A.C. electrification needs significant capital cost economies. However，the use of overhead equipment carried on simplified supporting structures，a consequence is that disturbances of the contact wire movement which emphasizes the need for a dynamic simulation. Refer to the relative references and seminar research reports it shows that the catenary uses scientific material and under improved version avail to research furthermore to increase in the running speeds and power supply quality of electrified railway. Analysis the exist power supply system of TRA，the overhead line systems necessary continuously improved to keep with the increase in the running speeds of electrified railway. Even if the peripheral environment factors caused the electrified railway to keep exist running speed，at least power supply system of electrify railway get increase power supply quality. This paper used the characteristic and track lines environment conditions of TRA exist overhead contact line system as parameter executed simulation under a slightly improved the catenary to keep with the increase in operating speed. The significant performance of this paper was the improvement of exist catenary being measured and verified by catenary inspection car. We expect this paper will be useful for future studies in the overhead contact lines system of upgrade speed and power supply quality.

碩士
南台科技大學
工業管理研究所
95
Following the rapid development of Tainan Science Park in recent years, the power usage is growing in the Park area every year. Besides, the production facilities of these high-tech factories inside the Park are highly sensitive; therefore, they are susceptible to factors such as accidents of power supply system and unstable power quality. For providing stable, sufficient, high quality power to satisfy the demand of the factories in Park area and for avoiding production interruption and substantial economic loss because of power supply system accident and unstable power quality, it is imperative for the Taiwan Power Company and other government agencies to expedite the planning and construction of the power supply system facilities in the Park area. Hence, the purpose of this study was to investigate the major aspects and key factors of power supply reliability and power quality, using grey analytical hierarchy process, and address specific strategies for improvement. Study results may help to provide major information on improving power supply reliability and power quality in Tainan Science Park and therefore, benefit the policy-making process in Taiwan Power Company and other government agencies for more effective and sound decisions. This study began with supply/demand analysis and power supply system accident analysis in Tainan Science Park. Secondly, according to the results of power supply system accident analysis, relevant literatures for the past years domestically or abroad and professional opinions from Taiwan Power Company and Tainan Science Park Administration Offices, we deliberated to look for the significant aspects and factors of power supply reliability and power quality. Then, we proceeded with the hierarchy structural drawing of “Evaluation and analysis of the key factors for Tainan Science Park power supply reliability and power quality.” After expert questionnaire design and survey, we calculated the significance of every aspect and factor in affecting the power supply reliability and power quality using gray analytical hierarchy process; and thus proceeded with the sorting according to the priority of importance. Finally, we focused on the most important seven key factors which influence the power supply reliability and power quality in Tainan Science Park to provide specific and feasible suggestions for power supply businesses (Taiwan Power Company and IPP power plant), industries in Park area, Tainan Science Park Administration Offices and manufactures of power supply equipments and materials. According to the analysis results in the study, the most important aspect which has effect on the power supply reliability and power quality in Tainan Science Park is “technical operation”; and the most important seven key factors are as follows: “human errors”, “work negligence”, “reinforce the supervision of construction”, “establish important dual-loop power supply capacity”, “equipment defect”, “improper design”, and “lack of improvement equipment”. Based on the above-mentioned seven key factors, we proposed the following important, specific and feasible strategies for improvement: 1. For Taiwan Power Company: (1) For avoiding “human errors”, education and training for the power supply system operating personnel on duty should be emphasized and standardized operational procedures should be implemented; accident drills should be held at least once every year for preparing both of power supply businesses and industrial subscribers. (2) For avoiding “work negligence”, maintenance staffs are required to be familiar with maintaining the function and operation of the facilities in the factory. Proceed with maintenance tasks based on system maintenance manual and standardized operational procedures for safety precaution. (3) For reinforcing the supervision of construction, it is required to send personnel to supervise power supply transmission and distribution. (4) For establishing important dual-loop power supply capacity, build dual-loop power supply capacity in SanFuKe substation in the Park area and individual independent dual-loop power supply for high voltage users (161 kV). (5) For avoiding the accidents caused by “equipment defect”, examine and maintain power supply facility periodically, and keep files for relevant maintenance records; establish a system for reserving components or spare parts of the facility and equipment for urgent repair in emergency; develop measures for updating major facility of power supply system so that the defective, outdated with insufficient capacity can be replaced. (6) Enforce strict regulations on power system designers to follow the design standards and related laws rigorously, to prevent the occurrence of accidents due to “improper design”. (7) Upgrade the stilted power lines in the park into underground power lines, to prevent voltage sag due to natural disaster or contact with foreign objects. 2. For IPP power plant: Same as the (1), (2), and (5) suggestions for Taiwan Power Company. 3. For the industrial subscribers in the Park area: (1) For avoiding the accidents caused by “human errors”, implement measures of power supply system operation and maintenance; improve on-the-job training for electric operating staffs; and require certification of all personnel for promoting the quality of staffs.(2) For avoiding accidents caused by “work negligence”, except the second suggestion for Taiwan Power Company, it is strictly forbidden to allow uncertified staffs to operate or maintain equipments. (3) For avoiding accidents caused by “equipment defect”, same as the suggestion. (5) for Taiwan Power Company. (4) For improving the problem of voltage sag, it is suggested to use commercialized voltage sag improvement equipment. 4. For the Tainan Science Park Administration Offices: (1) For avoiding the accidents caused by “human errors”, provide assistance to conduct certification test for the electric operating staffs of industrial subscriber in the Park area so that the certification system can be implemented and the quality of electrical operating staff can be promoted. (2) For avoiding the accidents caused by “reinforce the supervision of construction”, it is required to notify Taiwan Power Company for sending people to assist the supervision when the contractors or industrial subscribers are working on the construction under (on the side of) the transmission or distribution electric wires. 5. For the manufacturers of power supply equipments or materials: (1) For avoiding the accidents caused by “equipment defect”, improve testing and quality control procedures to assure quality before the products leave the factory. (2) Develop contingency and back-up plans for emergency situation so that the clients can be prepared and provided with reserved parts for urgent repair in critical condition to ease off their loss.

碩士
大葉大學
事業經營研究所碩士在職專班
94
Under the limit of “ the hospital total amount benefit system”, and as in the current trend of emphasizing customer satisfaction and treating customers kindly, while maintaining the medical treatment service quality and reducing the hospital operating maintenance cost, it is a new challenge that the hospital owners have to meet. Essential factors which influence the hospital service quality structure carried out by the Administration Business Department has unexpectedly occupied approximately 40%. Therefore, the hospital has to continuously improve the working place to be able to discover what service quality provided by the Administration Business Department is that the staff, patient, and patient’s family members care about. The service the customer truly expects needs to be understood to be able to avoid what the customer does not desire and only then can the hospital provide the service under the lowest maintenance cost to satisfy the customer. This research adopts the questionnaire research method and carries on the research with quantification, which discusses what the customer is looking forward to in the service provided by the Administration Business Department, including the difference and similarity of the value and total satisfaction and discusses the relationship between service expectation and total satisfaction. 923 questionnaires were sent out to customers with 642 being returned to show an effective rate of 98.3% participation. Using the T test, the variation number and the Pearson accumulating data methods to complete the statistical analysis, the results are as follows: Firstly, many different customer backgrounds reflect different expectations for the quality of service provided by the hospital. Secondly, different customer backgrounds reflect different views of total satisfaction of the quality of service. Thirdly, there is obviously a relationship between the expectation of service quality on the “Value degree” scale and customer satisfaction on the “Satisfaction degree”scale. This research also brings the suggestions to the decision-making departments and the business maintenance & administration department, providing the reference for future improvement.

碩士
華夏科技大學
資產與物業管理系
107
This study focuses on the analysis of the stability of power supply quality in high-rise building commercial buildings. Improving the power quality and harmonic suppression of high-rise commercial buildings has always been an important topic for property management companies. Because the harmonic source interference of high-rise commercial buildings will cause extra loss, overheating or overload of power transformation equipment and information hardware equipment. Worst of all can result in equipment damage and wasted power. This study is based on the position of a property management company to explore the following topics. First, suppress harmonics in high-rise commercial buildings. Second, reduce power consumption. Third, ensure the system operates normally under complicated load conditions. This study takes the harmonic improvement strategy of the power system of TAIPEI 101 as a case to discuss the harmonic control technology and how to reduce harmonics. In the power distribution system of TAIPEI 101, the number of users and the industry category of tenants are different and that will reflect on their power consumption, demand and load characteristics. The load status of each substation represents the load characteristics of each area. The non-linear load will increase when the leased area of the commercial building is increasing. At the same time, the power supply equipment of the commercial building is also relatively complex, which causes harmonic pollution to become more serious. The solution is to use the harmonic distortion rate formula and SF1001 harmonic analysis software to decide the active filter capacity and install position in the power system. The harmonic improvement results show that reducing THD(I) is obvious after the harmonic suppressor is put into operation. The accident probability is reduced and the device flash frequency phenomenon is also eliminated. In addition, power factor is also significantly improved. It reduces the system's reactive power and effectively improves the harmonic interference problem. The use of such harmonic improvement schemes is a reference for property management companies to make decisions. It is of great help to save manpower and time.

碩士
明新科技大學
管理研究所碩士在職專班
105
The power supply system is the main source for the public infrastructure in ITRI Guangfu District. The system is a single loop system. It was constructed in 1983, and has been operated for more than 33 years. Since the need of electricity has grown during these years, the probability of the power cutoff may increase, and the use of the system may cause great economical losses, because the power cannot be immediately restored in cases such as abnormal performance of high voltage cables when using the system. Thus, I thought that the system needed to be improved. After summarizing the opinions of owner (ITRI Guangfu District), architects, electrical technicians and electromechanical consultants, I focused on the improvements of the three parts in the old system, that is, the total substation, the high voltage relay station double switch, and the high pressure plate monitoring shift control system. Next, I used the method of resolve technical contradictions in TRIZ theory to help me found out the most practical scheme for the improvement, and the best scheme was the addition of "the addition of high-voltage vacuum circuit breakers", "switch box to add foolproof device", and "additional shift switch" in the previous system.

Testing integrated circuits to verify their operating frequency, known as delay testing, is essential to achieve acceptable product quality. The high cost of functional testing has driven the industry to automatically-generated structural tests, applied by low-cost testers taking advantage of design-for-test (DFT) circuitry on the chip. Traditional at-speed functional testing of digital circuits is increasingly challenged by new defect types and the high cost of functional test development. This research addressed the problems of accurate delay testing in DSM circuits by targeting resistive open and short circuits, while taking into account manufacturing process variation, power dissipation and power supply noise. In this work, we developed a class of structural delay tests in which we extended traditional launch-on-capture delay testing to additional launch and capture cycles. We call these Pseudofunctional Tests (PFT). A test pattern is scanned into the circuit, and then multiple functional clock cycles are applied to it with at-speed launch and capture for the last two cycles. The circuit switching activity over an extended period allows the off-chip power supply noise transient to die down prior to the at-speed launch and capture, achieving better timing correlation with the functional mode of operation. In addition, we also proposed advanced compaction methodologies to compact the generated test patterns into a smaller test set in order to reduce the test application time. We modified our CodGen K longest paths per gate automatic test pattern generator to implement PFT pattern generation. Experimental results show that PFT test generation is practical in terms of test generation time.

碩士
國防管理學院
後勤管理研究所
93
In a move to excel its competitiveness,Taiwan Power Company has enlisted the power relays as a core technology.with a small number of ultra high-voltage power users continue to contribute greatly to Taipower's operations. In a move to curtail loss in market share following the deregulation of the power market.This has made enuancing its power supply system protective structure,improving power relay's protection quality,together with heeding to acustomer-orientated service,as a major facus to be examined by the research insititute. 　　According to statistical analysis,key study findings derived include, 　　(1)Taiwan Power Company has a fine overall image and a good service attitude. 　　(2)Its subscribers generally have a high anticipation of Taiwan Power Company,and view the firm rather favorably in actuality. 　　(3)Its subscribers do recognize the quality of Taipower's power relay protection,and regard the self-diagnostic feature of its quality of power relay protection as outstanding. 　　It is advisable that Taipower reduces unwarned power disruption by offering additional service information.It is recommendable that the subscribers speed up replacing their power relay protection equipment by bring up the existing rate of power relay retirement and replacement work, as well as excelling their power relay protection engineering technology.

Полосарьов С. М. Аналіз впливу окремих показників якості електричної енергії на економічні показники виробництва в умовах ПрАТ «Дніпроспецсталь» : кваліфікаційна робота магістра спеціальності 141 "Електроенергетика, електротехніка та електромеханіка" / наук. керівник С. А. Левченко. Запоріжжя : ЗНУ, 2020. 73 с.
UA : Досліджено оказники якості електроенергії системи електропостачання заводу відмінні від нормативів; розроблено рекомендацій щодо нормалізації якості електроенергії; розраховано втрати потужності і електричної енергії в системі внутрішньозаводського електропостачання; досліджено енергетичні показники якості електроенергії.
EN : The indicators of the quality of electricity of the power supply system of the plant are different from the standards; developed recommendations for the normalization of electricity quality; losses of power and electric energy in the system of internal factory power supply are calculated; energy indicators of electricity quality are investigated.

碩士
南台科技大學
高階主管企管碩士班
94
Abstract The purposes of this study are to know the perceptions of employees,who were influenced in organization changes and their jobs were redesigned,QWL(The quality of work life ) toward job characteristics, and job involvement, This study applied questionnaires to collect research data. There were 340 Taipower employees, in 6 regions of power branch, participated in this research. Used windown10 SPSS program, run the research data and statistical inference, the author concludes that: 1. To average the research data of organization changes in Taipower power supply system substation maintenance sections, the satisfying level is in “passable” zone. 2. Compared that research data of 4 variables ( organization changes,QWL, job characteristics, and job involvement), the best perception is job involvement. 3. The achievement of organization changes may influence QWL directly. 4. During the process of organization changes, leaders’ support may increase employees’ positive perceptions toward organization changes. According to the above conclusions, the author proposes the following suggestions: 1. By enhancing respect for the job, employees will increase their recognitions to the decision and importance of jobs, and job characteristics. 2. Leaders should push the process of organization changes initially without to find troubles. 3. By enhancing the quality of work life achieved employees’ requirements. 4. To bring up right job attitudes may increase their recognitions to the job. 5. Company should prevent outside force to influence the achievement of organization changes. Key words: job characteristics, QWL, organization changes, job characteristics, outside force influence, job involvement.

In the recent years, governments have encouraged the utilization of renewable energy by providing incentives to investors, and enhancing traditional practices in the sector. For example, in Ontario, Canada, local distribution companies can now legally own and operate up to 10 MW generating plant per location as long as it is from a renewable source. Although this trend results in some operational benefits for the host networks, it also creates specific technical challenges and economic problems. New modeling approaches are needed to account for the main features of power produced by these facilities, namely, the uncertainty and uncontrollability. The uncertainty of power produced by weather-based generating facilities affects the decisions of different activities related to the operation of distribution systems. Examples of these tasks include power procurement decisions, the assessment of voltage magnitude variation, and reactive power management. If not properly included, uncertainty could result in non optimal outcome of operational activities of a distribution system operator. Based on different optimization techniques, the thesis introduces several models that capture the uncertain behavior of renewable resources. Two operational tasks were selected for application using the enhanced models: economical operation of distribution system and impact assessment on voltage magnitude. The power procurement problem is an operational challenge to acquire the correct economic mix of power purchases to supply the demand of a local distribution company. Three models have been presented to formulate the power procurement problem with a consideration of the stochastic nature of renewable generation. These models select the optimal quantities of bilateral contracts under uncertain renewable generation and give the option to decision makers to recalculate the powers from other sources. In one of these proposed models, the mean-variance theory is utilized to evaluate the risk associated with the variation of renewable power output on the financial efficiency of a local distribution company. Unlike previous studies, in which renewable power production is identified as a decision variable, in this work the generation from these units is represented as a parameter to model their feature of uncontrollability. Comparison of results obtained from using the proposed models showed that the degree of uncertainty plays an important role in selecting the proper mix. In general, stochastic based algorithms are superior to deterministic approaches when increasing contributions from renewable resources are considered. A major technical problem that may be caused by the uncertain generation of renewable units is the increase of voltage variation. The second part of the thesis introduces a methodology based on a Monte-Carlo technique to assess new installation depending on its impact on the quality of supply voltage. Two different standard measures for supply voltage quality are applied in this approach to provide the decision maker a tool that can be used to authorize new connections of renewable generation. The consistency of results obtained by the two indices applied in the proposed methodology encourages adopting the proposed approach for evaluating the impact of new connections of renewable resources. The models proposed in the thesis contribute to promote safer integration of renewable resources in distribution systems by modeling two main features: uncertainty and non-controllability.

Dissertação do mestrado em Engenharia Eletrónica Industrial e Computadores
A Qualidade de Energia Elétrica (QEE) é um tema cada vez mais importante no ramo da engenharia, pois os problemas na rede elétrica podem levar a que os equipamentos não funcionem corretamente. Isso, faz com que muitos clientes, no sector industrial serviços tenham prejuízos económicos muito elevados. Porém, muitos desses problemas ocorrem devido às cargas utilizadas pelos clientes que “poluem” a rede elétrica com potência reativa e harmónicas. Existem equipamentos de eletrónica de potência que mitigam estes problemas de Qualidade de Energia Elétrica, entre eles o Condicionador Unificado de Qualidade de Energia (Unified Power Quality Conditioner - UPQC). Esta dissertação aborda uma nova topologia deste equipamento chamado Condicionador Unificado de Qualidade de Energia com Controlo Invertido (iUPQC) Monofásico com a adição de baterias, para permitir o modo de alimentação ininterrupta da instalação (Uninterruptible Power Supply – UPS) denominando-se assim iUPQC-UPS. Um UPQC é um equipamento constituído por um condicionador ativo série (Conversor CC-CA) e um condicionador ativo paralelo (Conversor CC-CA) que ligam a um barramento CC comum. Este barramento irá ligar às baterias a partir de um conversor CC-CC bidirecional. O objetivo do UPQC com controlo invertido é que o condicionador ativo série absorva da rede a potência ativa necessária impondo uma corrente sinusoidal do lado da rede, enquanto que o condicionador ativo paralelo fornece às cargas uma tensão sinusoidal com frequência e valor eficaz normalizado. Desta forma, todas a potência reativa e harmónicas serão fornecidos pelo condicionador ativo paralelo. Esta dissertação apresenta um estudo bibliográfico dos condicionadores ativos de potência que mitigam os problemas de QEE, das topologias dos conversores de potência e dos seus algoritmos de controlo. Com base neste estudo, foi usada a ferramenta PSIM para fazer simulações dos modos de funcionamento do iUPQC-UPS. Posteriormente, foi desenvolvido o protótipo do iUPQC-UPS, constituído pelo sistema de controlo, sistema de comando e sistema de potência. Por ultimo, o protótipo foi validado ao retirar os resultados experimentais de todos os modos de funcionamento.
Electrical Power Quality is an increasingly important topic in the engineering field, as the problems created in the electrical network lead to the equipment not working properly. This causes many customers in the industrial services sector to have very high economic losses. However, many of these problems occur due to the loads used by customers that “pollute” the Electric Grid with reactive power and harmonics. There are power electronics equipment that mitigate these Power Quality problems, among them the Unified Power Quality Conditioner (UPQC). This dissertation approaches a new topology of this equipment called Unified Power Quality Conditioner with Inverted Control (iUPQC) with the addition of batteries, to allow the uninterruptible power supply of the installation (Uninterruptible Power Supply - UPS), thus called iUPQC- UPS. This equipment consists of a series active conditioner (DC-AC converter) and a parallel active conditioner (DC-AC converter) that connect to a common DC bus. This bus will connect to the batteries from a bidirectional DC-DC converter. The objective is that the series active conditioner absorbs the necessary power from the power grid while imposing a sinusoidal current on the power grid side, while the shunt active conditioner provides the loads with a sinusoidal voltage with normalized frequency and effective value. In this way, all reactive power and harmonics will be provided by the shunt active conditioner The batteries will charge or discharge as needed by the network. That is, if the power of the network is greater than the power of the loads, the batteries will use power from the network to charge. If the power of the network is less than the power of the loads, the batteries will discharge when supplying power to the loads.
Este trabalho de dissertação está enquadrado no projeto IC&DT “Quality4Power – Enhancing the Power Quality for Industry 4.0 in the era of Microgrids”, financiado pela Fundação para a Ciência e Tecnologia, com a referência PTDC/EEI-EEE/28813/2017

Dissertação de mestrado em Engenharia Eletrónica Industrial e de Computadores
Atualmente, a utilização de cargas não-lineares na rede elétrica é uma constante. Este tipo de cargas leva a uma degradação da Qualidade de Energia Elétrica, uma vez que consome harmónicos de corrente, prejudicando o transporte e a distribuição de energia e o funcionamento da maioria dos equipamentos ligados à rede elétrica. Para além disso, em determinados sistemas há cargas que necessitam de ser alimentadas ininterruptamente, tais como controladores de processos industriais, computadores, equipamentos médico e sistemas de comunicação de dados, pelo que estas cargas não podem depender exclusivamente da rede elétrica, uma vez que, sendo esta suscetível a falhas, terá de ser complementada por geradores de emergência ou UPSs (Uninterruptible Power Supplies – fontes de alimentação ininterruptas). Deste modo, torna-se necessário o desenvolvimento e a utilização de equipamentos capazes de mitigar os problemas acima referidos. No Grupo de Eletrónica de Potência e Energia (GEPE) da Universidade do Minho têm sido desenvolvidos Filtros Ativos de Potência para compensar problemas de Qualidade de Energia. Assim sendo, neste trabalho de Mestrado foi proposto o desenvolvimento de um Filtro Ativo Paralelo Monofásico com operação como UPS. Este equipamento é capaz de compensar o fator de potência e os harmónicos de corrente em condições normais de funcionamento da rede elétrica e é também capaz de alimentar, de forma isolada, um conjunto de cargas prioritárias perante eventuais falhas na rede. Para além disso, foi também desenvolvido um conversor CC-CC bidirecional isolado com o intuito de carregar as baterias a partir da rede elétrica, através do barramento CC do Filtro Ativo Paralelo, bem como injetar energia na rede elétrica isolada proveniente das mesmas. Pretendeu-se que o equipamento desenvolvido fosse leve, compacto e com operação silenciosa, de modo a poder ser instalado no quadro elétrico de uma habitação. Deste modo, alguns procedimentos foram tomados aquando do projeto da solução apresentada, tais como a escolha dos semicondutores de potência e dos elementos magnéticos a utilizar. No final, foi efetuado um levantamento de custos da solução obtida de modo a analisar a sua viabilidade comercial.
Nowadays, the use of nonlinear loads connected to the electrical power grid is unceasing. This kind of electrical loads leads to Power Quality declining, since it consumes harmonic currents, worsening power transmission and distribution and the proper operation of a vast amount of power grid connected equipment. Furthermore, there are loads connected to several power systems that need incessant power supplying, such as industrial process controllers, computers, medical equipment and datacenters, whereby these loads cannot depend exclusively upon the power grid, since it is vulnerable to power outages, and therefore must be complemented by emergency generators or UPSs (Uninterruptible Power Supplies). Therefore, the development and use of equipment capable of mitigating these issues is needed. The Group of Energy and Power Electronics (GEPE) of the University of Minho has been developing Active Power Filters to compensate for Power Quality problems. Thus, the development of a Single-Phase Shunt Active Power Filter with UPS operation was proposed in this Master's thesis work. This equipment is capable of compensating for power factor and harmonic currents during normal operation of the power grid, and is also able to supply with isolation a set of priority electrical loads towards eventual power outages. Besides that, a bidirectional isolated DC-DC converter was developed in order to charge the battery pack from the power grid, through the Shunt Active Power Filter DC-link, as well as to provide energy stored in the batteries to the isolated electrical power grid. It was intended for the equipment to be weightless, compact and silent in order to be installed in a domestic electrical switchboard. Consequently, several procedures were taken during the solution’s development, such as the power semiconductors and the magnetic elements selection. In the end, it was performed the costing of the obtained solution with the purpose of evaluating its commercial feasibility.

New emission legislation regarding air pollution control, as instructed by the Department of Environmental Affairs (DEA) to Eskom Generation Power Stations, implies a particulate emission limit of 100 mg/Nm3 for all existing power stations by 2015 and 50 mg/Nm3 for all new and existing power stations by the year 2020. Some of Eskom’s power stations which are equipped with Electrostatic Precipitators (ESP’s) were not designed for this stringent legislation. It is also experienced that ESP’s and coal quality in Eskom have deteriorated over time, resulting in the performance of the ESP’s not meeting the legislative requirements. Eskom is in the process of introducing various ESP enhancement projects to improve performance and aligning the operating philosophy to comply with the more stringent particulate emission legislation. An ESP efficiency test was conducted at Lethabo Power Station to determine the current state of the plant and performance. The results of the test were compared with the original design base specifications to determine the relevant deficiencies which contribute to high emissions and poor ESP performance. It was aimed to develop an ESP simulation model and validate the outputs with the test data. This study endeavours to demonstrate the greater impact on ESP performance when the ESP is operated outside the design specification. It is further aimed to demonstrate that a solution to the problem of high emissions is not only contributed by the variables within the ESP itself. This study is a coal to stack evaluation considering the ESP variables and the upstream conditions of the ESP that form part of the entire process. The intention of this study is to demonstrate the importance of operating an ESP at the designed parameters and highlight the significance of proper maintenance. It was learned that before any ESP enhancement technology can be implemented, the ESP and upstream conditions must be in accordance with design specifications. The implementation of an ESP enhancement technology will have no merit or justification on a unit that is being operated outside of its design specifications. The results obtained from the ESP simulation model correlated well with the ESP efficiency test data. The expectation of the model to assist operators and engineers to operate ESP’s according to the designer’s specifications was conceded.
MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014