Дисертації з теми "Uninterruptible power supply system"
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Rahmat, Mohd Khairil. "Methods for reliability analysis of uninterruptible power supply (UPS) system." Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444418.
Повний текст джерела
2
Cheng, Limin. "A universal controller for a single-phase uninterruptible power supply system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0001/MQ42361.pdf.
Повний текст джерела
3
Schmidt, Uwe. "Uninterruptible power supply system using a dual converter in quasi-resonant mode." Thesis, Brunel University, 1995. http://bura.brunel.ac.uk/handle/2438/5410.
Повний текст джерелаАнотація:
Uninterruptible Power Supply (UPS) systems have become a standard to protect electronic devices such as servers and host computers. Also, the energy supply of whole buildings is linked with large UPS systems to ensure a steady power flow. Two system configurations are widely used which differ in price and their ability to protect very sensitive load. This thesis illustrates an analytical examination of all existing systems and concludes with the finding of new configurations with increased efficiency and reduced costs. A dual converter is proposed as the heart of the new UPS system. This converter links the necessary two sources of the UPS through a common transformer. The transformer operates at a high frequency which is enabled due to the resonant switching technique used. The results of this paper were achieved using mathematical analysis, electrical and electro-magnetic simulation as well as by experiments carried out on the self designed circuit boards in the laboratory. These boards were built in a modular way to enable series testing and thereby optimise the dimensioning of the system.
4
Karsli, V. M. "An investigation into real-time microcontrolled single phase uninterruptible power supply systems." Thesis, Swansea University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637763.
Повний текст джерелаАнотація:
Recent developments in power electronic switching devices and microprocessors have led to power electronic systems with high efficiency and reliability. Today, high performance and low cost are the requirements to be met for most practical systems. This work describes the development of real-time based Uninterruptible Power Supply systems (UPS) which can operate on-line and off-line. Synchronous operation is an inevitable condition in off-line UPS systems. Here, back-synchronisation after a power failure is achieved automatically with the pre-set values. A new modified regular sampled symmetric pulse width modulation method has been developed, it has many advantages especially in low frequency applications. High switching frequency (18 kHz) reduces significantly the filtration and noise problems in UPS systems. Phase delay associated with transformer, filter, load, and control algorithm might cause drastic power failures in by-pass switches, thus to overcome this problem, phase shift control algorithms are developed. PID control algorithm is simplified for real-time on-line operation at high switching frequency. The complete system is based on a single Intel 80C196KC microcontroller chip and the developed software has the flexibility for further development. The developed system has been tested in the laboratory under linear load condition and the results are given. The test results are found to be satisfactory for most load conditions.
5
Beran, Edward W. "An electromagnetic interference analysis of uninterruptible power supply systems in a data processing environment." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FBeran.pdf.
Повний текст джерелаАнотація:
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002.Thesis advisor(s): Richard W. Adler, Wilbur R. Vincent. Includes bibliographical references (p. 103-104). Also available online.
6
Marwali, Mohammad Nanda Rahmana. "Digital control of pulse width modulated inverters for high performance uninterruptible power supplies." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1100484647.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xviii, 224 p.; also includes graphics. Includes bibliographical references (p. 199-211).
7
Barnes, Lemuel Gregory. "Voltage-source inverter output waveform compensation using adaptive intelligent control /." This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10192006-115605/.
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Aminou, Moussavou Anges Akim. "Modelling and analysis of microgrid control techniques for grid stabilisation." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/1184.
Повний текст джерелаАнотація:
Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Electrical Engineering
in the Faculty of Engineering
at the
Cape Peninsula University of Technology
2014In recent times, renewable energy-based distributed generation (DG) has captivated the industrial sector and on a global scale this has become a leading research area. Distributed generation using wind, solar energy or biomass as a source of energy can produce electricity on a small scale. Therefore, there is a strong focus on using renewable energy as a safe alternative source of energy, especially because it can in future play a dominant role in the world’s energy production and help to tackle the increase of global warming caused by fossil energy. However, a major problem facing renewable energies is that they are highly dependent on weather conditions. Since the power generated by DG, as well as consumption, depends on the weather conditions, irregularity of production and consumption leads to frequency and voltage fluctuations, and it can become difficult to determine and monitor consumer usage at any given time. Distributed generation can then be subjected to discrepancies in consumer usage and this can lead to severe overloading. As a result, microgrids powered by DG, operating in a single, stand-alone controllable system mode, face new challenges in terms of balancing a cluster of loads. Balancing a cluster of loads by making sure at all times that the entire system operates without overloading, is an essential requirement for the proper operation of a power system. The microgrid load considered in this project is the sum of sensitive and non-sensitive loads, respectively 5 kW and 100 kW, which constitute load requirement of one village; this total load required by a number of villages is called a cluster load. Depending on the input power generated by a DG-based photovoltaic (PV) system, these loads can be controlled using a logic control switch (LCS). When the power produced is less than the minimum load required by a component of a cluster, overloading occurs. The purpose of using an LCS is to ensure that a stable system is maintained under various loads and resource conditions. An LCS is used to continuously monitor and adjust load through circuit breakers. It is a good alternative to load balancing for a cluster of villages in rural area where a microgrid is operating in stand-alone mode. The focus of this research is to design a photovoltaic system with a maximum capacity of 1 MW providing power to a cluster of rural villages, and operating in stand-alone mode, and then to apply different control techniques (droop control, dq0 reference frame + proportional integral (PI) controller, and PI controller alone) at the inverter terminal of the PV system, in order to evaluate the stability of the output voltage. Another goal of the research is to develop an energy management system (EMS) algorithm to support the PV system in reducing loads. Therefore, a iii stable system under various load and resource conditions, as well as suitable control mechanisms are required to model a PV system. There is a need for the modelling of a PV array using a physical modelling block in MATLAB (SIMULINK) software. The state flow provided by SIMULINK is used in this project to develop an algorithm for load balancing. The state flow gives possibilities of modelling complex algorithms by combining graphical and tabular representations to create sequential decision logic, derived from state transition diagrams and tables, flow charts and truth tables. Furthermore, the design of a microgrid using photovoltaic DG and an energy management system, has been developed. The present work mainly consists of a stand-alone microgrid operation, where the power generated must be equal to the load power. In addition, different control methods, consisting of a dq0 reference frame + PI controller, are analysed at the invertor terminal. Subsequently an LCS algorithm is developed; this is required to maintain the system within certain limits and prevents overloading. LCS algorithms are based on a flowchart and allow switching automatically selected loads, depending on the power (solar radiation) available. In addition, a flow chart provides an easy way of using a graphical transition state and state chart to establish a set of rules for the system. The simulation results show that both droop control and a dq0 reference frame + PI controller are much better than a PI controller alone; these results also compared well with similar studies found in the literature. Also, these results are further improved with an EMS in order to maintain the output voltage of the microgrid, by switching on and off certain loads depending on the input power. The modelling of the microgrid using DG, based on photovoltaic systems with a maximum capacity of 1 MW, supports and improves the PV system by reducing loads. Moreover, droop control, and dq0 transformation + PI control present a better result than PI controller alone.
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Milad, Muftah A. "UPS system : how current and future technologies can improve energy efficiency in data centres." Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/14664.
Повний текст джерелаАнотація:
A data centre can consist of a large group of networked servers and associated power distribution, networking, and cooling equipment, all that application consumes enormous amounts of energy as a small city, which are driving to a significant increase in energy inefficiency problems in data centre, and high operational costs. Also the massive amounts of computation power contained in these systems results in many interesting distributed systems and resource management problems. In recent years, research and technologies in electrical engineering and computer science have made fast progress in various fields. One of the most important fields is the energy consumption in data centre. In recent years the energy consumption of electronic devices in data centre, as reported by. Choa, Limb and Kimb, nearly 30000000 kWh of power in a year, may consume by a large data centre and cost its operator around £3,000,000 for electricity alone. Some of the UK sites consume more than this. In the UK data centre the total power required are amid 2-3TWh per year. Energy is the largest single component of operating costs for data centres, varying from 25-60%. Agreeing to many types of research, one of the largest losses and causes of data centre energy inefficiency power distribution is from the uninterruptible power supply (UPS). So a detailed study characterized the efficiencies of various types of UPSs under a variety of operating conditions, proposed an efficiency label for UPSs, also investigate challenges related to data centre efficiency, and how all new technologies can be used to simplify deployment, improve resource efficiency, and saving cost. Data centre energy consumption is an important and increasing concern for data centre managers and operators. Inefficient UPS systems can contribute to this concern with 15 percent or more of utility input going to electrical waste within the UPS itself. For that reason, maximizing energy efficiencies, and reduce the power consumption in a data centre has become an important issue in saving costs and reducing carbon footprint, and it is necessary to reduce the operational costs. This study attempts to answer the question of how can future UPS topology and technology improve the efficiency and reduce the cost of data centre. In order to study the impact of different UPS technologies and their operating efficiencies. A model for a medium size data centre is developed, and load schedules and worked diagrams were created to examine in detail and test the components of each of the UPS system topologies. The electrical infrastructure topology to be adopted is configured to ‘2N’ and ‘N+1’ redundancy configuration for each UPS systems technologies, where ‘N’ stands for the number of UPS modules that are required to supply power to data centre. This work done at RED engineering designs company. They are professionals for designing and construction of a new Tier III and Tier IV data centres. The aim of this work is to provide data centre managers with a clearer understanding of key factors and considerations involved in selecting the right UPS to meet present and future requirements.
10
Jacobsson, Erik. "Dimensionering av UPS-system och generatorer för reservkraftsystem på sjukhus och flygplatser." Thesis, Karlstads universitet, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-69399.
Повний текст джерелаАнотація:
Sjukhus och flygplatser är precis som resten av samhället, beroende av el. Med dagens teknik är sjukhus och flygplatser högteknologiska ochväldigt störningskänsliga för elbortfall,vilket gör det viktigt att ha en stabil och säker kraftförsörjning utan avbrott. Ett avbrott i strömförsörjningen kan orsaka allvarliga,till och med livsfarliga konsekvenser. Att säkerställa ett bra och redundant reservkraftsystemär väsentligt för sjukhusen och flygplatserna. Syftet med studien var att undersöka samt ta fram reservkraftsystem med redundansförsjukhus och flygplatser. Under arbetets gång har litteraturstudie om generatorer och UPS-system (uninterruptible power supply) gjorts samt intervjuer med experter inom båda ämnena. Resultat visar de fundamentala delarna som är viktiga att ta hänsyn till vid dimensionering av reservkraftsystem. Men det visar också på att det finns många faktorersom spelar in vid dimensionering av systemen, vilket leder till att alla system ser olika ut och det finns inte riktigtnågon specifik mall att följa.Hospitals and airports are just like the rest of society, dependent onelectricity. With today's technology, hospitals and airports are highly technological and highly sensitiveto electricity loss. Thatmakes it important to have stable and secure power supply without interruptions. An interruption of power supply can cause serious even fatal consequences. Ensuring a good and redundant reserve power system is essential for hospitals and airports. The purpose of the study was to investigate and provide good redundant solutions for reserve systems in hospitals and airports. During the course of the thesis, literature studies ofgenerators and UPS (uninterruptible power supply) systems have been conducted as well as interviews with experts in both subjects.Results show the fundamental aspects that should be taken into account when dimensioning reserve power systems. But it also shows that there are many aspects that affectthe system dimensioning, which means that all systems look different and there is no specific template to follow.
11
Kanduri, Venkata Ramanujam. "Distributed generation impact on fault response of a distrubution [i.e., distribution] network." Master's thesis, Mississippi State : Mississippi State University, 2004. http://library.msstate.edu/etd/show.asp?etd=etd-11122004-151757.
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Aucamp, Christiaan Daniël. "Model predictive control of a magnetically suspended flywheel energy storage system / Christiaan Daniël Aucamp." Thesis, North-West University, 2012. http://hdl.handle.net/10394/8601.
Повний текст джерелаАнотація:
The goal of this dissertation is to evaluate the effectiveness of model predictive control (MPC)
for a magnetically suspended flywheel energy storage uninterruptible power supply (FlyUPS).
The reason this research topic was selected was to determine if an advanced control technique
such as MPC could perform better than a classical control approach such as decentralised
Proportional-plus-Differential (PD) control.
Based on a literature study of the FlyUPS system and the MPC strategies available, two MPC
strategies were used to design two possible MPC controllers were designed for the FlyUPS,
namely a classical MPC algorithm that incorporates optimisation techniques and the MPC
algorithm used in the MATLAB® MPC toolbox™. In order to take the restrictions of the system
into consideration, the model used to derive the controllers was reduced to an order of ten
according to the Hankel singular value decomposition of the model.
Simulation results indicated that the first controller based on a classical MPC algorithm and
optimisation techniques was not verified as a viable control strategy to be implemented on the
physical FlyUPS system due to difficulties obtaining the desired response. The second
controller derived using the MATLAB® MPC toolbox™ was verified to be a viable control
strategy for the FlyUPS by delivering good performance in simulation.
The verified MPC controller was then implemented on the FlyUPS. This implementation was
then analysed in order to validate that the controller operates as expected through a
comparison of the simulation and implementation results. Further analysis was then done by
comparing the performance of MPC with decentralised PD control in order to determine the
advantages and limitations of using MPC on the FlyUPS.
The advantages indicated by the evaluation include the simplicity of the design of the controller
that follows directly from the specifications of the system and the dynamics of the system, and
the good performance of the controller within the parameters of the controller design. The
limitations identified during this evaluation include the high computational load that requires a
relatively long execution time, and the inability of the MPC controller to adapt to unmodelled
system dynamics.
Based on this evaluation MPC can be seen as a viable control strategy for the FlyUPS, however
more research is needed to optimise the MPC approach to yield significant advantages over
other control techniques such as decentralised PD control.Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013
13
Badeda, Julia [Verfasser], Dirk Uwe [Akademischer Betreuer] Sauer, and Antonello [Akademischer Betreuer] Monti. "Modeling and steering of multi-use operation with uninterruptible power supply systems utilizing the example of lead-acid batteries / Julia Badeda ; Dirk Uwe Sauer, Antonello Monti." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/121517148X/34.
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Pedral, Jacques, and Josef Abriren. "Analys av lågspänningsfördelning till signalanläggningar." Thesis, KTH, Data- och elektroteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192837.
Повний текст джерелаАнотація:
I denna rapport utreds hur systemdesignen av lågspänningsfördelningen för järnvägen kan kostnadseffektiviseras. I dagsläget har det utarbetats en norm kring systemdesignen som tenderar att efterbildas från år till år vilket har medfört brist på innovation inom området. Syftet med arbetet var att designa två typstationer med signalställverken M11 respektive M95, där placering samt nominell storlek av UPS:er skulle fastställas för att tillhandahålla en kostnadseffektiv lösning. Dessutom skulle kablage dimensioneras för typstationerna samt se över möjligheten att ersätta UPS:er med likriktarsystem. Stationerna baserades på två redan existerande driftplatser, Fagersta C (M11) och Skänninge (M95). Slutligen skulle olika energilagringsalternativ för UPS-system jämföras för att tillhandahålla det lämpligaste alternativet. Genom simuleringar och beräkningar i bland annat datorprogrammet El-Vis har lågspänningsfördelningen dimensionerats för typstationerna. Arbetet visar på att ett distribuerat UPS-system är att föredra ur ett ekonomiskt perspektiv gentemot ett centraliserat UPS-system. Vidare har det konstaterats att likriktarsystemet Rectiverter kan ersätta UPS:er samt att ackumulatorer är det mest passande energilagringsalternativet.This report identifies how the system design of low voltage power distribution of the railway can be more cost effective. In the current situation there is a norm on the system design that tends to be replicated each year. This has brought a lack of innovation in the field. The purpose of the thesis was to come up with two model stations with the interlocking system M11 respectively M95, where the positioning and nominal size of the UPS:s would be determined to provide a cost effective solution. Furthermore, the cable dimensioning of the model stations was computed as well as the possibility of replacing UPS-systems with rectifier-systems. The model stations were based on two already existing operating sites, Fagersta C (M11) and Skänninge (M95). Lastly, different energy storage alternatives for UPS-systems were compared to acquire the most appropriate choice. Through simulations and calculations in, inter alia, the computer program El-Vis, the low voltage power distribution was dimensioned for the model stations. The thesis shows that a distributed UPS-system is preferred in an economical point of view compared to a centralized UPS-system. Furthermore, the thesis establishes that the rectifier system Rectiverter can replace UPS:s. It also states that accumulators are the most suitable alternative for energy storage.
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Barnes, Lemuel Gregory III. "Voltage-source inverter output waveform compensation using adaptive intelligent control." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/39997.
Повний текст джерелаАнотація:
A single-layer neural network-based voltage compensation technique which generates minimum-distortion sinusoidal output voltages from a three-phase PWM inverter used for uninterruptible power supplies (UPS) is described. The proposed compensation technique is implemented in a microprocessor-based controller constructed in the stationary d-q frame where the controller sampling rate is twice the inverter switching frequency. The structure of a feed-forward artificial neural network connects network inputs and outputs through multiple linear or nonlinear
neuron models, and processes these input/output data associations in a
parallel distributed manner. Network inputs in the form of UPS load voltage commands and load current feedback are propagated forward in the network each controller sampling period generating the inverter output voltage commands, the network outputs, which are converted to three phase inverter switching Signals using the space vector PWM waveform generation process.Ph. D.
16
Vieira, Carlos Eduardo. "UPS híbrida: integração de uma fonte alimentação ininterrupta com um sistema de geração fotovoltaico." Master's thesis, Instituto Politécnico de Setúbal. Escola Superior de Tecnologia de Setúbal, 2016. http://hdl.handle.net/10400.26/16849.
Повний текст джерелаАнотація:
Dissertação submetida como requisito parcial para
obtenção do grau de Mestre em Engenharia
Eletrotécnica e de Computadores – perfil de
Energias Renováveis e Sistemas de PotênciaEste trabalho apresenta estruturas híbridas para um sistema de alimentação ininterrupta (UPS) com a integração de um sistema fotovoltaico (PV). Atualmente, a forma mais segura de fornecer energia para os equipamentos críticos ou sistemas de processamento de dados é efetuada a partir da utilização de uma UPS do tipo on-line. Por outro lado, normalmente não é requerida mesma segurança de uso num sistema fotovoltaico. Nesta dissertação serão apresentadas topologias para a integração de ambas tecnologias, de modo a gerar e fornecer energia de qualidade para as cargas críticas. Tendo em consideração a integração do sistema PV na UPS, logo esta também poderá funcionar desvinculada da rede, desde que a energia produzida pelo PV seja suficiente. A primeira das soluções é baseada numa estrutura de dupla conversão clássica. No entanto, será apresentada uma solução alternativa baseada numa topologia de conversão do tipo multinível. Esta última estrutura, propõe a utilização de duas UPS interligadas por único transformador trifásico de enrolamentos abertos, na entrada e na saída do sistema. Os barramentos DC são independentes e conectados aos respectivos conversores de controlo do sistema PV e das baterias. Esta nova estrutura apresenta diversas vantagens, tais como, maior fiabilidade no fornecimento de energia para cargas críticas e na qualidade da forma de onda de saída. Para além das estruturas propostas, serão apresentados os correspondentes circuitos de controlo. Ambos os sistemas foram simulados em Matlab/ Simulink de modo a verificar através dos diversos resultados o potencial das soluções propostas.
This work presents hybrid structures for an uninterruptible power supply (UPS) with the integration of a photovoltaic system (PV). Currently, the safest way to supply energy to critical equipment or data processing system is established with the use of an online UPS. On other hand, normally it is not required to use the same security in a PV system. In this dissertation will present topologies for integration of both technologies in order to generate and provide quality power to critical loads. Considering the integration of the PV system in a UPS, therefore it may also work disconnected from the grid, as long as the energy produced by the PV is sufficient. The first of these solutions is based on a classical double conversion structure. However, it will be presented an alternative solution based on a multilevel conversion topology. This latter structure, proposes the use of two UPS connected by only one three- phase transformer of open windings, at the input and output of the system. The DC links are independent and connected to the respective control converters of the PV system and batteries. This new structure introduces many advantages such as high reliability in supplying power to critical loads and in the quality of the output waveform. In addition to the proposed structures, the corresponding control circuits will be presented. Both systems were simulated in Matlab/ Simulink in order to verify through various results the potential of the proposed solutions.
17
Gnoatto, Claudio Lucas. "Estratégias de controle repetitivo para aplicação em sistemas de alimentação ininterrupta de energia." Universidade Tecnológica Federal do Paraná, 2011. http://repositorio.utfpr.edu.br/jspui/handle/1/222.
Повний текст джерелаАнотація:
CAPESEste trabalho tem como objetivo a análise, projeto e implementação de estratégias de controle repetitivo para aplicação em sistemas de alimentação ininterrupta de energia (UPS - Uninterruptible Power Supply). Inicialmente, a revisão da literatura aborda os controladores mais aplicados neste propósito. Uma visão geral sobre sistemas UPS é realizada, com foco em diferentes topologias e o projeto de um filtro indutivo capacitivo (LC), para reduzir o conteúdo harmônico proveniente das comutações do inversor, é discutido. Na sequência, uma estratégia de controle é proposta. Nesta estratégia um termo feedforward é utilizado para gerar a forma de onda da tensão de saída e um controlador do tipo proporcional derivativo (PD) é inserido para compensar distúrbios não cíclicos. Para compensação de distúrbios cíclicos, algumas técnicas de controle repetitivo são analisadas e implementadas. A adição destes controladores apresenta bom desempenho, porém, quando o sistema sofre interferências, as características dinâmicas destes controladores são afetadas. Modificações são realizadas para tornar o sistema menos suscetível a ruídos de alta frequência e a distúrbios aperiódicos. Ainda, é proposto um controlador repetitivo com adaptação do ganho que apresenta robustez suficiente para boa regulação de tensão mesmo na presença de distúrbios aperiódicos e interferências eletromagnéticas. Por fim, é descrita a implementação de uma plataforma flexível, baseado em um inversor PWM controlado por um processador digital de sinais com periféricos para aquisição de dados e geração de PWM, DSC TMS320F28335. A partir desta plataforma, foram obtidos resultados experimentais para um protótipo de uma UPS monofásica, os quais comprovam o desempenho das técnicas de controle apresentadas e propostas.
This work presents an analysis, design and implementation of repetitive control strategies applied to uninterruptible power supplies (UPS) systems. At the beginning, a literature review of the main controllers concerning this purpose is shown. A global vision of UPS systems with focus on different topologies is made and the project of an inductive capacitive filter (LC) is presented where the goal is to reduce harmonic content due to the inverter switching. After that, a control strategy is presented. In this strategy a feed forward term is used to generate the wave form shape of the output voltage and a Proportional Derivative (PD) controller is introduced to compensate non cyclic disturbances. For the compensation of cyclic disturbs some repetitive control techniques are analyzed and implemented. The inclusion of these controllers provides a good performance for the output system, however, when the system is exposed to interferences, the dynamic characteristics of these controllers are affected. Modifications are presented to make the system less susceptible for high frequencies noise and aperiodic disturbs. In addition, a repetitive controller with gain adaptation is proposed with sufficient robustness to obtain a good voltage regulation even in the presence of aperiodic disturbances and electromagnetic interferences. Finally, the implementation of a flexible platform is presented, based on PWM inverter controlled by a digital signal processor with data acquisition and generation PWM peripherals, DSP TMS320F28335. From this platform, experimental results for a monophasic UPS prototype was obtained, which ones prove the performance of the control techniques presented and proposed.
18
Pan, Haibo 1973. "SMES for power quality improvement and uninterruptible power supply." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33342.
Повний текст джерелаАнотація:
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.
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Миколаєць, Дмитро Анатолійович. "Фільтро-компенсуючий перетворювач в системі гарантованого електроживлення". Doctoral thesis, Київ, 2015. https://ela.kpi.ua/handle/123456789/17617.
Повний текст джерелаАнотація:
Дисертація присвячена розробці теоретичних і практичних засад побудови системи гарантованого електроживлення на базі фільтро-компенсуючого перетворювача.
В роботі розроблено математичні моделі та виведено аналітичні вирази, які дозволяють визначити основні параметри силової частини фільтро-компенсуючого перетворювача, а також законів його керування, при функціонуванні з системою заряду акумулятора. Запропонована система електроживлення на базі фільтро-компенсуючого перетворювача здатна виконувати як функцію джерела безперебійного живлення, так і компенсатора реактивної потужності. З використанням методу розрахунку системи за середніми значеннями струмів та напруг при врахуванні відношення між енергіями навантаження та заряду акумулятора розраховані параметри реактивних елементів та величини задавальних струмів та напруг, необхідних для забезпечення ефективної роботи системи. Спрощені методи розрахунку напруги конденсатора фільтро-компенсуючого перетворювача з використанням регулювальних характеристик та балансу енергій, а також амплітуди вхідного струму дозволяють значно знизити затримку мікропроцесорної системи керування при обчисленні керуючих впливів. Використовуючи метод заряду акумулятора імпульсним асиметричним струмом, забезпечується подовження терміну служби батарей. В системі гарантованого електроживлення на базі фільтро-компенсуючого перетворювача необхідно враховувати збільшення ємності накопичувального конденсатора. Основні теоретичні викладки роботи підтверджуються результатами комп’ютерного моделювання.
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Beber, DG. "DSP controlled three phase to single phase uninterruptible power supply." Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/5244.
Повний текст джерелаАнотація:
Includes bibliographical references.With the increase in use of electronic equipment such as personal computers, network stations and AC drive conrollers, an increased "polution" of the AC mains has resulted in the form of unwanted harmonics generated by the switching currents associated with these devices. Combined with the problem of mains "pollution" is the problem of balancing a large number of single phase loads onto a three phase supply, such as in a large computer network. This has resulted in more frequent supply voltage failure, causing substantial data and financial loss and in the extreme case death due to hospital equipment not being powered. Thus the need for an uninterruptible power supply (UPS) which is capable of resolving these problems. Taking these considerations into account, a three to single phase converter topology was developed and tested, using a Texas Instruments TMS320F243 Digital Signal Processor (DSP) for control of the system. The topology is based on a technique that utilises minimal semiconductor devices whilst still allowing for sinusoidal current to be drawn from the mains supply.
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Zhang, Hai Bo. "High-frequency switching parallel processing topology for AC uninterruptible power supply." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ40215.pdf.
Повний текст джерела
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Annunziato, Rafael Christiano. "Projeto e implementação de método para conexão paralela de UPSs com compartilhamento de potência." Universidade Tecnológica Federal do Paraná, 2012. http://repositorio.utfpr.edu.br/jspui/handle/1/312.
Повний текст джерелаАнотація:
Este trabalho apresenta o projeto e a implementação prática de um método completo para ser utilizado na conexão de UPSs monofásicos em paralelo. Existe um algoritmo que executa o droop de fase/frequência, e um novo método que trabalha com e sem comunicação de dados entre os inversores. Quando a comunicação está ativa, um novo algoritmo é utilizado, inserindo um resistência virtual variável, junto com o compartilhamento de potência ativa, obtendo um baixo valor de THD (Total Harmonic Distortion) na tensão de saída e bom compartilhamento de potência. Quando a comunicação de dados não funciona, uma resistência virtual constante é inserida, aumentando a THD de saída com carga não-linear, mas ainda proporcionando um bom compartilhamento de potência ativa. A vantagem é poder obter um bom desempenho quando a comunicação de dados está operando, mas, no caso de sua falha, o sistema ainda funciona, proporcionando maior confiabilidade. A implementação possui um algoritmo de emulação de carga eletrônica, com o propósito de executar testes de produção, baseado no mesmo algoritmo de paralelismo, apenas mudando algumas variáveis.This work presents the design and experimental implementation of a complete paralleling method to be used for parallel single-phase UPSs connection. There is a algorithm that performs a phase/frequency droop, and a new method to work with or without data communication among the inverters. When communication is working, a new algorithm is used, inserting a variable virtual resistance in the output, along with active power sharing, obtaining a low output voltage THD (Total Harmonic Distortion) value and good power sharing. Without communication a constant virtual resistance is inserted, increasing the output THD with non-linear load, but still allowing a good active power sharing. The advantage is to obtain a good performance operation with communication, but, in case of communication failure, the system still works providing more reliability. The implementation have a electronic load emulation algorithm, with purpose to execute factory tests, based in the same parallelism algorithm, just changing some variables.
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Cetinkaya, Suleyman. "Repetitive Control Of A Three-phase Uninterruptible Power Supply With Isolation Transformer." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608150/index.pdf.
Повний текст джерелаАнотація:
A repetitive control method for output voltage control of a three phase uninterruptible power supply (UPS) with isolation transformer is investigated. In the method voltage control loop is employed in the stationary dq frame. The controller eliminates the periodic errors on the output voltages due to inverter voltage nonlinearity and load disturbances. The controller design and implementation details are given. The controller is implemented on a 5-kVA UPS prototype which is
constructed in laboratory. Linear and nonlinear loads for balanced and unbalanced load operating conditions are considered. The steady-state and dynamic performance of the control method are investigated in detail. The theory of the control strategy is verified by means of simulations and experiments.
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Mikros, Efthimios. "Mitigation of EMI/RFI produced by a 1.2 kW uninterruptible power supply." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from the National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA273149.
Повний текст джерелаАнотація:
Thesis (M.S. in Systems Engineering) Naval Postgraduate School, September 1993.Thesis advisor(s): Adler, Richard William. "September 1993." Includes bibliographical references. Also available online.
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Magozore, Caxton. "DSP phase angle controlled three phase to single phase uninterruptible power supply." Master's thesis, University of Cape Town, 2003. http://hdl.handle.net/11427/5177.
Повний текст джерела
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Bellinaso, Lucas Vizzotto. "Inversores fotovoltaicos conectados à rede com armazenamento de energia – classificação, recomendações técnicas e gerenciamento." Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/13314.
Повний текст джерелаАнотація:
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPqGrid-connected photovoltaic systems with energy storage have features of conventional gridconnected inverters and uninterruptible power supplies. In these systems, all elements, which include photovoltaic generator, batteries, loads and electric grid, are connected to the same equipment named multifunctional photovoltaic converter. As it is a recent technology, there are many research opportunities in this theme, from classifications and standards to specific problems. This study investigates this field in a comprehensive manner, proposing classifications, technical recommendations and a power management strategy. Initially, classifications are proposed considering system configuration and continuity of supply to the loads. In the following, technical recommendations related to grid and load compatibility, as well as safety technical recommendations, are proposed. The last proposal consists on a power management strategy which defines the operation mode of the static converters and system elements as a function of the energy scarcity. Experimental results of the power management are presented in order to validate the proposals. In this way, this thesis contributes to the development of multifunctional photovoltaic converters technology so that the distributed generation becomes more independent of solar availability and can better collaborate with the electric system.
Sistemas fotovoltaicos conectados à rede com armazenamento de energia são aqueles que conjugam características dos inversores conectados à rede convencionais e de fontes ininterruptas de energia. Nesses sistemas, todos os seus elementos, que incluem o gerador fotovoltaico, as baterias, as cargas e a rede elétrica, são conectados a um mesmo equipamento chamado de conversor fotovoltaico multifuncional. Por se tratar de uma tecnologia recente, existem muitas oportunidades de pesquisa inédita no tema, desde premissas e classificações básicas até a solução de problemas mais específicos. Este trabalho investiga o tema de maneira abrangente, propondo classificações, recomendações técnicas e uma estratégia para gerenciamento interno de potência dos conversores fotovoltaicos multifuncionais. Inicialmente, classificações são propostas considerando a configuração do sistema e a continuidade de fornecimento de energia às cargas. A seguir, são propostas recomendações técnicas relacionadas à compatibilidade com a rede e com as cargas, além de recomendações técnicas de segurança, baseando-se em normas existentes. A última proposta consiste em uma estratégia de gerenciamento interno de potência que define os modos de operação dos conversores estáticos e dos elementos do sistema em função da escassez de energia. Resultados experimentais do método proposto para o gerenciamento interno de potências são apresentados com o objetivo de validar as propostas desenvolvidas. Dessa forma, o presente trabalho contribui com o desenvolvimento da tecnologia de conversores fotovoltaicos multifuncionais, para que a geração distribuída de energia elétrica se torne mais independente da disponibilidade solar e possa melhor colaborar com o sistema elétrico.
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Humphrey, Daniel Alan. "Fuel cells as a backup energy source for high availability network servers." Texas A&M University, 2008. http://hdl.handle.net/1969.1/86024.
Повний текст джерелаАнотація:
This thesis proposes an uninterruptible power supply, UPS for high availability
servers with fuel cells as its back up energy source. The system comprises a DC to DC
converter designed to accommodate the fuel cellâ s wide output voltage range. A server
power supply is specified, designed and simulated for use with this UPS. The UPS
interfaces internal to the server power supply, instead of providing standard AC power.
This topology affords enhanced protection from faults and increases overall efficiency of
the system by removing power conversions. The UPS is simulated with the designed
power supply to demonstrate its effectiveness.
28
Tate, D. "A microprocessor controlled error switching inverter used in the uninterruptible power supply environment." Thesis, University of Bath, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275883.
Повний текст джерела
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Marwali, Mohammad Nanda. "Digital control of pulse width modulated inverters for high performance uninterruptible power supplies." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1100484647.
Повний текст джерела
30
Höglund, Jonatan. "Redundans vid manöver med hjälp av UPSpå elnätet." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-50407.
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SANTOS, Gustavo Maciel dos. "Estudo do acoplamento de grupos Motor-Gerador com Uninterruptible Power Supply aplicando Wavelets e Redes Neurais Artificiais." Universidade Federal de Pernambuco, 2011. https://repositorio.ufpe.br/handle/123456789/5320.
Повний текст джерелаАнотація:
Made available in DSpace on 2014-06-12T17:38:05Z (GMT). No. of bitstreams: 2
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Previous issue date: 2011Com a sociedade globalizada e a evolução da informática, o conceito de horário comercial não é mais simples. Transações bancárias, negociações na bolsa de valores e compras pelo computador ocorrem em qualquer horário e as empresas precisam garantir a disponibilidade de seus serviços sempre. Para garantir o fornecimento ininterrupto de energia para estes sistemas de informações são utilizados grupos motorgerador (GMG) e uninterruptible power supply (UPS). Quando há dificuldade de acoplamento entre os dois equipamentos, na prática, os projetistas superdimensionam o GMG em relação ao UPS sem embasamento teórico para esta ação. Este estudo propõe apresentar a correlação entre os dados de placa desses equipamentos e o distúrbio de tensão entre eles para proporcionar uma maior segurança no dimensionamento de sistemas com UPS e GMG. A metodologia desse estudo propõe o uso de Redes Neurais Artificiais (RNA s) para descrever esta correlação e transformada wavelet para destacar os distúrbios medidos e auxiliar na convergência da RNA em seu treinamento. Os resultados obtidos com as redes desenvolvidas neste trabalho sugerem que o menor distúrbio no sinal, obtido devido ao acoplamento de UPS e GMG, ocorrerá se as potências dos equipamentos (dados de placa) forem próximas, independente do nível de carregamento do sistema. À medida que esta relação se distancia do valor unitário, a perturbação aumenta e um UPS com potência menor que o GMG contribui mais com a distorção do sinal do que ao contrário
32
Eireiner, Matthias. "Power supply integrity in low power designs." Aachen Shaker, 2009. http://d-nb.info/99845642X/04.
Повний текст джерела
33
Uys, Jacobus Johannes. "Dynamic digital control schemes for three-phase UPS inverters." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52810.
Повний текст джерелаАнотація:
Thesis (MScEng)--University of Stellenbosch, 2002.ENGLISH ABSTRACT: This thesis presents the design and implementation of a voltage controller for an Uninterruptible Power Supply (UPS) Inverter. The inverter is capable of producing a nearly sinusoidal output voltage waveform, thereby keeping the Total Harmonic Distortion (THD) to a minimum. Digital controllers introduce a time delay in the control law that causes system instability. Various control techniques, which includes Pade approximations and system augmentation, are investigated to eliminate the effect of the time delay. These controllers employ classical control as well as modem control techniques. The selection of the various control parameters is verified by mathematical equations. A load-disturbance compensation scheme, implementing feed-forward and gain scheduling, is also developed to improve voltage distortion when varying loads, such as non-linear loads, are connected to the system. It is shown that the constructed pulse-width modulated (PWM) control scheme can achieve fast dynamic response as well as a low THD.
AFRIKAANSE OPSOMMING: Hierdie verhandeling ondersoek die ontwerp en implementering van 'n spanningsbeheerder vir 'n ononderbroke kragtoevoer omsetter. Die stelsel produseer 'n uittree spannigsgolfvorm met 'n lae Totale Harmoniese Distorisie (THD). Digital beheerders veroorsaak 'n tydvertraging in die beheerwet wat stelsel onstabiliteit kan veroorsaak. Verskeie beheertegnieke wat gebaseer is op die Pade benaderings van die tydvertraging en stelsel aanpassings, is ondersoek. Hierdie beheerders maak gebruik van klassieke en moderne beheertegnieke. Die seleksie van die verskeie beheerderveranderlikes word gestaaf deur wiskundige vergelykings. Spannigsvervorming word tot 'n minimum beperk deur gebruik te maak van 'n lasveranderings-kompensasietegniek wat onderskeidelik vorentoe-voer en aanwins skedulering implementeer. Verder word daar bewys dat die pulswydte modulasie (PWM) beheerskema vinnige dinamiese gedrag asook 'n lae THD bewerkstellig.
34
Zitouni, Salah. "An expert system for electric power system management." Thesis, University of Dundee, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338200.
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35
Song, Jian, Ni Luo, Liu Cao, and Min Xu. "An Evaluation System for Airplane's Power Supply." International Foundation for Telemetering, 2015. http://hdl.handle.net/10150/596441.
Повний текст джерелаАнотація:
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NVPower supply is the most critical unit in an airplane. A defect in a power supply might lead to a crash. Therefore, it is very useful and important to monitor the status of the airplane's power supply during flight. This paper presents a real-time evaluation system constructed by a central process unit for processing and detecting defects and several remote units for acquiring parameters. Because of the huge amount of data acquired, a combination of Ethernet and time division multiplexing technique has been applied for constructing a 2.5Gbps synchronous data transportation network for the system.
36
Chan, Weng Hong. "Harmonic reduction and power factor correction in low power supply system." Thesis, University of Macau, 2002. http://umaclib3.umac.mo/record=b1445817.
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37
Tsao, Chun-Ming, and 曹俊銘. "An FPGA Based Uninterruptible Power Supply System." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/00743975209337731996.
Повний текст джерелаАнотація:
碩士國立成功大學
電機工程學系碩博士班
94
This thesis proposes an uninterruptible power supply (UPS) system with digital and analog controller to realize this system. The DC/AC inverter uses a field-programmable gate array (FPGA) as a controller to achieve the digital pulse-width-modulation (PWM) control. Then, the verilog hardware description language (VHDL) is used to write the control procedures and ISE6.3 is served as the software development platform to perform syntax testing. Furthermore, the power factor correction (PFC) circuit, the charge circuit, and the spare power circuit are controlled by analog circuits. In addition, the FPGA is used to control the battery charge and spare power circuits. Under the normal utility-line power supply condition, the boost PFC circuit provides DC bus voltage the load and also maintain battery at the highest capacity. While the utility-line power is abnormally interrupted, the batteries supply the energy for the inverter to maintain a stable AC voltage supply for the load system. Finally, a 600W UPS system is implemented to verify the functionalities of the proposed designs.
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Chandorkar, Mukul C. "Distributed uninterruptible power supply systems." 1995. http://catalog.hathitrust.org/api/volumes/oclc/34608544.html.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--University of Wisconsin--Madison, 1995.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 170-173).
39
Palamar, A. "Intelligent Control and Monitoring Module for Uninterruptible Power Supply System." Thesis, 2020. https://openarchive.nure.ua/handle/document/17535.
Повний текст джерелаАнотація:
This paper proposes an intelligent control and monitoring module for industrial uninterruptible power supply systems. The structure scheme of the module based on the parallel connected of two microcontrollers with ARM architecture is designed. The software for the module is developed and implemented.
40
TAI, JEN-HAO, and 戴仁豪. "Design and Implementation of a FPGA-Based Uninterruptible Power Supply System." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/71941916426258603315.
Повний текст джерелаАнотація:
碩士國立成功大學
電機工程學系碩博士班
93
The design and implementation of a FPGA-based uninterruptible power supply (UPS) system is proposed in this thesis. The controller for the UPS system adopts analog and digital means. The analog IC is used to control power factor correction and the FPGA digital controller is employed to control the bi-directional buck-boost converter and DC/AC inverter. Under the normal AC line operation mode, the power factor correction circuit forces the input current to follow the input voltage to achieve high power factor. The output of power factor correction circuit is then fed to the load through a DC/AC inverter and the battery is charged simultaneously via bi-directional buck-boost converter. During the utility power failure condition, the battery of voltage is boosted through bi-directional DC/DC converter and then transferred to the load by DC/AC inverter. Finally, Spartan-II-XC2S200 FPGA is employed to realize a 600VA UPS and the experimental results are performed to verify the theoretical discussion.
41
Yang, Li Ming, and 李明陽. "Design of a Harmonic Elimination Pulse Width Modulated Uninterruptible Power Supply System." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/32428924374685362059.
Повний текст джерелаАнотація:
碩士國立臺北教育大學
資訊科學系碩士班
97
In this thesis, a field programmable gate array (FPGA) - based harmonic elimination pulse width modulation (HEPWM) generator for an uninterruptible power supply is proposed. The HEPWM generator is developed in two steps. First, the off-line computations of switching patterns based on harmonic elimination strategy are stored in EPROM. Then, the circuits for adjustments of modulation index and phase angle are synthesized onto a FPGA by means of hardware description language (VHDL). The developed chip applied to an uninterruptible power supply which is composed of a series lead-acid battery, a push-pull converter and two half bridge inverters each supplying a separate single-phase load at 220VAC, 60Hz. In order to meet the required load voltage and reduce the space occupied by the batteries, the push-pull converter is used to boost the 36VDC from series batteries to 320VDC at a switching frequency of 29.4kHz. The switching patterns of the push-pull converter are also programmed into the FPGA. Experimental results from 1kVA FPGA-based laboratory UPS verifies the effectiveness and accuracy of the proposed configuration.
42
JUNG-MING, CHENG, and 鄭榮明. "Development of Multi-functional Single-Phase Uninterruptible Power Supply Systems." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/52968365658424176113.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電機工程系
96
This thesis is concerned with the analysis and implementation of multi-functional single-phase uninterruptible power supply systems. Besides possessing reactive power compensation capability, additional supercapacitors, which can enhance the power output energy when grid power fails instantly, are introduced to improve the current of battery discharge. The system uses single-phase full-bridge structure with sinusoidal pulse-width-modulation and unipolar switching technique to provide output voltage with low harmonic distortion and fast response for inverter. The dc-to-ac power converter operates under voltage-controlled mode by using amplitude-locked loop algorithm to achieve the aforementioned low harmonic distortion under single-phase loads. As to the management of energy storage components such as battery and supercapacitors, the charging/discharging schemes are controlled properly by a buck/boost dc chopper. In this system, a high-performance, low-cost digital signal processor TMS320LF2812 is used to host the control system. All control rules are realized by software. It can not only reduce the hardware cost but also improve system reliability. The experimental results for linear load of 250W show that the total harmonic distortion of output voltage is 4.09 %, which complies with IEEE Std. 519-1992. In addition, the proposed system can yield power compensation for the inductive load of 120W and 128Var under normal utility operation. The design objectives of introducing supercapacitors to assure uninterruptible power supply with smooth battery discharging current when utility power failure occurs are also verified experimentally.
43
Liao, Kuo-An, and 廖國安. "Parallel Operation Control of Inverters for Photovoltaic Uninterruptible Power Supply Systems." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/38902686631487286244.
Повний текст джерелаАнотація:
碩士國立雲林科技大學
電機工程系碩士班
89
This thesis presents a control technique for operating two or more single phase inverter modules in parallel with no auxiliary interconnections. In the proposed parallel inverter system, all the modules have the same circuit configuration, and each module includes an inner current loop and an output voltage loop control. With power sharing control, the load sharing can be automatically achieved and the output current of each inverter can be accurately limited to its maximum rating. This technique uses frequency and fundamental voltage droop to allow all independent inverters to share the load in proportion to their capacities. From the simulation and experiment results, the proposed control for PVS inverters is verified.
44
Wang, Kuo-Cheng, and 王國丞. "Design and Implementation of Parallel Type Three-phase Uninterruptible Power Supply Systems." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/56638494191890576260.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電機工程系
95
This thesis is concerned with the design of three-phase expandable parallel multi-functional uninterruptible power supply (UPS) systems. The system communication is conducted by controller area network (CAN). When the AC mains is normal, the proposed system provides compensating reactive power using current-controlled mode. Whereas, if the AC mains fails, the system will supply the battery power to the load with master/slave control. The master UPS operates under voltage-controlled mode, while all the other converters function under current-controlled mode. If the UPS under voltage-controlled mode fails, one of the UPS under current-controlled mode will be changed to voltage-controlled mode to provide stable AC voltage. Thus, each UPS can either provide AC voltage source independently, or be connected with others in parallel for capacity expansion. The control scheme of the system is implemented by a 16-bit digital signal processor to reduce the hardware components. The experimental results for 1030 W linear resistive load show that the total harmonic distortion of output voltage is 1.32 %. Each UPS can share current and output power evenly.
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Chang, Hsiu Wei, and 張修維. "Design and Implementation of Rotary-Type Three-Phase Uninterruptible Power Supply Systems." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/51100769214788849609.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電機工程系
96
This thesis is concerned with the design and implementation of rotary-type, three-phase uninterruptible power supply (UPS) systems. In this system, a permanent-magnet synchronous motor is used to drive an excited-type synchronous generator to generate three-phase electrical power to loads. The full-bridge diode rectifier is used to convert the utility to dc source for inverter to drive the permanent-magnet synchronous motor. Besides, batteries can release energy when utility fails to assure the supply of dc source voltage. The current control method of synchronous frame with closed-loop speed control mechanism is used to maintain constant motor speed. On the other hand, the dc chopper in accordance with the feedback of three-phase voltage is designed to adjust the exciting current for synchronous generator, and thereby outputs the three-phase electrical power with constant-voltage and constant-frequency. A high-performance, low-cost, 16-bit digital signal processor (DSP, TMS320LF2407A) is used as the control core. The control of motor and inverter is accomplished by software for reducing the circuit complexity. A prototype of 600W synchronous motor with speed control system is developed. Finally, experiments are given to justify the feasibility of the proposed system.
46
Wu, Chung-Der, and 吳俊德. "Design and Implementation of Layer Architecture Software Modules for Uninterruptible Power Supply Systems." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/75046454923894536264.
Повний текст джерелаАнотація:
碩士輔仁大學
電子工程學系
93
Because of the continuous development of global economics, computers, networks, and office automation, the quality of electric power is very important; hence, the need of UPS (Uninterruptible Power Supply) has risen. Different kinds of computers may be connected by complicated networks. In large-scale computer networks, UPS should take more responsibility, as the basic functions of previous UPS were limited. So we propose a layer architecture software module design for the UPS monitoring system. This UPS system monitors the situation of computers automatically. Not only the system security is including in, but also the graphic interface and real time battery monitor are supported. And all other abilities are provided for different kinds of UPS to support API interfaces and lets many monitoring software modules be connected through the design. Because of the layer architecture has the extendable characteristics, via the layer architecture, we easily extend the UPS design to Multi-Level-Server design across separated networks, and this function can manage and allocate electric power automatically. Compared to common network monitoring system, our design takes the way of centralized management and separated monitoring for large amount of computers. The design can also filter the transferring messages, adoptable management, and adjust the local loading balance to reach the global loading balance. In addition, we use a model of the queuing theory to make modeling and derivation, as well as use the simulation and measurement program, Webserver Stress Tool to make the simulation and experimental measurement. The simulation and measurement results show that the management efficiency of the layer architecture design for an UPS system has improved.
47
Yang, Jiou-Meng, and 楊久孟. "Development of Three-Phase Parallel Uninterruptible Power Supply Systems with the Function of Reactive Power Compensator." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/53614840266661310485.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電機工程系
93
This thesis is concerned with the implementation of three-phase parallel multi-functional uninterruptible power supply systems. The system consists of two three-phase three-leg parallel converters. When the AC mains is normal, the proposed system regulates its output current according to the AC load, and achieves compensating reactive power, reducing voltage regulation and charging battery. If the AC mains fails, the system will supply the battery power to the load with master/slave control. The first dc-to-ac power converter with double control loops provides stable AC voltage source with low harmonic distortion, whereas the second converter operates under current-controlled mode to provide harmonic compensation current or share load current based on different loads to improve system capacity. As to the management of batteries, the charging/discharging schemes are fulfilled by a boost/buck DC chopper. The performance of the system is first simulated with MATLAB/Simulink. The control scheme of the system is implemented by a 16-bit digital signal processor (DSP, TMS320LF2407A) to reduce the hardware components. The experimental results for 1380 W linear resitive load and 1030 W nonlinear load show that the total harmonic distortions of output voltage are 1.4 % and 5.5 %, respectively. Besides, the proposed system can yield power compensation for the inductive load of 630 W and 640 VAR under normal utility operation. Experimental and simulated data are given to justify the analysis.
48
Su, Yu-sheng, and 蘇育生. "Development of Digital Signal Processor Based Parallel-Type Single-Phase Uninterruptible Power Supply Systems." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/82358427176851675254.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電機工程系
92
This thesis is concerned with the analysis and implementation of single-phase multi-functional uninterruptible power supply systems. In this system, two single-phase dc-to-ac power converters are in parallel to convert power with low harmonic distortion and fast response for the output voltage through sinusoidal pulse-width-modulation (SPWM) unipolar switching technique. The first dc-to-ac power converter operates under voltage-controlled mode by using amplitude-locked loop (ALL) algorithm to provide output voltage with low harmonic distortion under linear / nonlinear loads, while the second converter operates under current-controlled mode to provide current harmonics for nonlinear loads and share load current as well. Therefore, the proposed system can not only convert power stably, but also supply load power. In addition, a Buck/ Boost DC chopper is designed to charge or discharge the battery set. The performance of the system is first simulated by using Matlab/Simulink. Then a 16-bit digital signal processor (DSP, TMS320LF2407A) is introduced to conduct the control function. The experimental results for 1.8kW linear load and 0.9kW nonlinear load show that the total harmonic distortion of output voltage is 3.2% and 5.6%, respectively. Besides, the voltage regulation is less than 2.0% for both linear and nonlinear loads. Experimental data are given to verify the feasibility of the proposed algorithm.
49
CHANG, LU YI, and 呂宜昌. "Development of Digital Signal Processor Based Single-Phase Half-Bridge Uninterruptible Power Supply Systems." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/18157564234426073054.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
電機工程系
92
Abtract This thesis presents the analysis and design of a single-phase, half-bridge uninterruptible power supply system. In this system, an active power factor corrector combined with rectifier and dc chopper is proposed to reduce hardware cost. The single-phase, half-bridge rectifier controlled by current prediction algorithm is used to yield unity power factor and reduce current harmonic on input side connected with utility. The voltage type, single-phase, dc-to-ac power converter controlled by current prediction algorithm is implemented by sinusoidal pulse-width-modulation technique to control output voltage stably. During power interruption of utility, the dc chopper can provide power transferred from batteries to maintain operation of power inverter. Besides, the voltage-balanced controller is designed to improve voltage imbalanced between the capacitors at the dc-link. A low-cost, high-speed, 16-bit digital signal processor (DSP TMS320LF2407A) is used to serve as the core control device to implement a 600W system under nonlinear loads. Experimental data show that the power factor and total harmonic distortion of current of the proposed power converter are 0.99 and 9.95%, respectively. Besides, total harmonic distortion of inverter voltage is around 8%. Finally, measurement data from experiments are given to justify the feasibility of the system design.
50
Du, Toit Johannes Paulus. "Design and development of a 100 W Proton exchange membrane fuel cell uninterruptible power supply." Thesis, 2006. http://hdl.handle.net/10352/286.
Повний текст джерелаАнотація:
M. Tech. (Engineering Department Applied Electronics and Electronic Communication, Faculty of Engineering) Vaal University of TechnologyThis study presents the design of a proton exchange membrane fuel cell stack that can be used to replace conventional sources of electrical energy in an uninterruptible power supply system, specifically for use in the telecommunications industry. One of the major concerns regarding the widespread commercialization of fuel cells is the high cost associated with fuel cell components and their manufacturing. A fuel cell design is presented in which existing, low-cost, technologies are used in the manufacture of cell components. For example, printed circuit boards are used in the manufacturing of bipolar flow plates to significantly reduce the cost of fuel cells. The first objective was to design, construct and test a single fuel cell and small fuel cell stack in order to evaluate the use of printed circuit boards in bipolar plate manufacturing. Since the use of copper in a fuel cell environment was found to reduce the lifetime of the cells, the bipolar plates were coated with a protective layer of nickel and chrome. These coatings proved to increase the lifetime of the cells significantly. Power outputs of more than 4 W per cell were achieved. The second objective was to analyze a small fuel cell stack in order to obtain a model for predicting the performance of larger stacks. A mathematical model was developed which was then used to design an electronic circuit equivalent of a fuel cell stack. Both models were adapted to predict the performance of a fuel cell stack containing any number of cells. The models were proven to be able to accurately predict the performance of a fuel cell stack by comparing simulated results with practical performance data. Finally, the circuit equivalent of a fuel cell stack was used to evaluate the capability of a switch mode boost converter to maintain a constant voltage when driven by a fuel cell stack, even under varying load conditions. Simulation results showed the ability of the boost converter to maintain a constant output voltage. The use of supercapacitors as a replacement for batteries as a secondary energy source was also evaluated.