Dissertations / Theses on the topic 'Electric power systems – Protection'
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Mguzulwa, Ncedo Richard. "Investigation of interoperability of IEC 61850 protection functions." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2704.
Full textIntroduction of IEC 61850 standard defined substation automation system communication. The need of interoperability among the relevant devices coming from different vendors is a necessity to ensure utilities/municipalities obtain value for money. Vendors used their own proprietary tools to achieve communication in a substation. This caused an Intelligent Electronic Device (IED) from vendor A could not communicate with an IED from vendor B. Utilities/municipalities are forced to depend on single vendor solutions in a substation automation system. IEC 61850 systems tout Interoperability as a major gain in the Substation Automation System (SAS) environment. The implementation of interoperable systems in SAS environment requires extensive testing and careful selection of vendors. This involves extensive testing to meet the required requirements of a certain SAS. Interoperability implementation and testing methods need to be formulated and tested rigorously with various scenarios of interoperability in an SAS. GOOSE messages form the foundation of IEC 61850 standard as they are responsible for the copper-less connections for peer to peer communications. GOOSE messages are based on peer to peer communications to enable interoperability at the bay level which is called horizontal communication. IEDs need to be carefully selected to ensure GOOSE messaging interoperability is achieved. Test methods are equally important as methodology to achieve interoperability. The purpose of this research is to perform an investigation on interoperability of IEC 61850 conformant IEDs based on evaluation of their protection functions. The research looks at various vendors on how each has interpreted the IEC 61850 standard. Also an analysis on requirements to achieve interoperability is conducted. Investigation on various vendor independent system configuration tools to ease the implementation burden of a multivendor application is done. Evaluation into flexible object modelling and naming conventions in order to achieve interoperability is performed. Various tests using different tools to assess the integrity of interoperability are completed. The research delivers a methodology to evaluate and implement GOOSE message interoperability. The interoperability methodology can be used for improvement of interoperability applications. The methodology can also be implemented as procurement requirement to ensure interoperability. The evaluation/implementation of interoperability can be included in Factory Acceptance Test (FAT). The methodology to achieve interoperability is only usefully when requirements are clear with regard to what needs to achieved by SAS.
Qadri, Syed Saadat. "A systematic approach to setting underfrequency relays in electric power systems /." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116022.
Full textThis thesis develops and tests a new systematic method for setting underfrequency relays offering a number of advantages over conventional methods. A discretized swing equation model is used to evaluate the system frequency following a contingency, and the operational logic of an underfrequency relay is modeled using mixed integer linear programming (MILP) techniques. The proposed approach computes relay settings with respect to a subset of all plausible contingencies for a given system. A method for selecting the subset of contingencies for inclusion in the MILP is presented. The goal of this thesis is to demonstrate that given certain types of degrees of freedom in the relay setting problem, it is possible to obtain a set of relay settings that limits damage or disconnection of generating units for each and every possible generation loss outage in a given system, while attempting to shed the least amount of load for each contingency.
Mthunzi, Everett Mondliwethu. "Performance analysis of a protection scheme based on P-class synchrophasor measurements." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2378.
Full textPower grid and system protection advancement greatly depend on technological advances. Advent technologies like digital microprocessor type protective relays facilitate paradigm shifts, providing inimitable beneficial engineering adaptations. Phasor measuring technology provides one such technological advance. The onset and rapid development of the Phasor Measuring Unit (PMU) provides an excellent platform for phasor-based, power system engineering. Power transmission constitutes a critical section in the electric power system. The power system transmission lines are susceptible to faults which require instant isolation to establish and maintain consistent system stability. This research focuses on the study of transmission line protection based on P-Class synchrophasor measurements. The IEEE C37.238-2011 Precision Time Protocol (PTP) paradigm shift facilitates practical application of synchrophasors in protection schemes. Synchrophasor procession and accurate data alignment over wide areas support the hypothesis of a phasor-based transmission line differential protection. This research aims to directly implement P-Class synchrophasors in transmission line differential protection, employing synchrophasors to determine fault conditions and administer corresponding protective actions in wide area transmission lines. The research also aims to evaluate the operational characteristics of the synchrophasor-based transmission line differential protection scheme. The research deliverables include a laboratory scale Test-bench that implements the PMU-based transmission line differential protection scheme, and a differential protection utility software solution that follows guidelines specified by the C37.118-2011 standard for synchrophasors. The findings stand to evaluate performance of the PMU-based line differential protection scheme, verifying the protection model as an alternate, practical and feasible backup protection solution. The research deliverables include a synchrophasor-based current differential algorithm, software utility for implementing the PMU-based protection scheme and a Test-bench for concept and feasibility validation.
Alvarez, Rogelio E. "Interdicting electrical power grids." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FAlvarez.pdf.
Full textThesis advisor(s): Javier Salmeron, R. Kevin Wood. Includes bibliographical references (p. 69-70). Also available online.
Mao, Yiming Mui Karen. "Protection system design for power distribution systems in the presence of distributed generation /." Philadelphia, Pa. : Drexel University, 2005. http://dspace.library.drexel.edu/handle/1860/501.
Full textAmann, Nicholas Paul. "Adaptive overcurrent protection scheme for shipboard power systems." Master's thesis, Mississippi State : Mississippi State University, 2004. http://library.msstate.edu/etd/show.asp?etd=etd-06282004-140248.
Full textSarawgi, Sanjoy Kumar. "A simulation tool for studying the effects of special protection systems and communications on power system stability." Online access for everyone, 2004. http://www.dissertations.wsu.edu/Thesis/Summer2004/s%5Fsarawgi%5F072604.pdf.
Full textLiu, Bohan. "Advanced ROCOF protection of distribution systems." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/14344/.
Full textHarris, Raymond Trevor. "Replacement of seven 132/66 kv distance protection schemes by means of a generic relay implemented as a strategic spare." Thesis, Port Elizabeth Technikon, 2000. http://hdl.handle.net/10948/34.
Full textKumbale, Murali. "Bulk transmission system reliability analysis of protection and control groups." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/13840.
Full textHamilton, Hymiar. "An impact study of DC protection techniques for shipboard power systems." Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-07062007-144823.
Full textThompson, Jeffrey Craig. "An expert system for protection system design of interconnected electrical distribution circuits." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-170345/.
Full textBaningobera, Bwandakassy Elenga. "The IEC 61850 standard-based protection scheme for power transformers." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2713.
Full textTransformer Differential and overcurrent schemes are traditionally used as main and backup protection respectively. The differential protection relay (SEL487E) has dedicated harmonic restraint function which blocks the relay during the transformer magnetizing inrush conditions. However, the backup overcurrent relay (SEL751A) applied to the transformer protection does not have a harmonic restraint element and trips the overcurrent relay during the inrush conditions. Therefore, to prevent the malfunction caused by the transformer magnetizing inrush current, a novel harmonic blocking method is developed, implemented and tested in the RSCAD simulation environment. The IEEE 14 bus transmission system is considered as a case study. The IEEE 14 bus system is modelled and simulated in the DIgSILENT and RSCAD simulation environments respectively. The developed harmonic blocking scheme is implemented in the Hardware-In-the-Loop (HIL) simulation environment using Real-Time Digital Simulator and numerical protection IEDs. The developed scheme uses the Harmonic Blocking element (87HB) of the transformer differential relay (SEL487E) to send an IEC61850 GOOSE-based harmonic blocking signal to the backup overcurrent relay (SEL751A) to inhibit it from tripping during the transformer magnetizing inrush current conditions. The hardwired and GOOSE simulation results are analysed for the transformer differential protection and the backup overcurrent protection schemes for internal, external events and transformer magnetizing inrush current conditions. The simulation results proved that the IEC61850 standard-based protection scheme is faster than the hardwired. Therefore, the speed and reliability are improved using the IEC61850 standard-based GOOSE applications to the transformer digital protective relaying system.
Garrett, Bretton Wayne. "Digital simulation of power system protection under transient conditions." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27303.
Full textApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Minkley, Warick. "Analysis of restricted earth fault relay application within a shunt capacitor bank design impacting on protection stability." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1021106.
Full textGammon, Tammy Lea. "Improved arcing-fault current models for low-voltage power systems (<1kV)." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/15675.
Full textManmek, Thip Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Real-time power system disturbance identification and its mitigation using an enhanced least squares algorithm." Awarded by:University of New South Wales. Electrical Engineering and Telecommunications, 2006. http://handle.unsw.edu.au/1959.4/26233.
Full textArès, Jean-Michel. "A knowledge-based model and simulator for alarm and protection systems of power networks /." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63921.
Full textMa, Tan. "Hybrid Power System Intelligent Operation and Protection Involving Plug-in Electric Vehicles." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/1760.
Full textAdewole, Adeyemi Charles. "Investigation of methodologies for fault detection and diagnosis in electric power system protection." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/1273.
Full textThe widespread deregulation and restructuring of electric power utilities throughout the world and the surge in competition amongst utility companies has brought about the desire for improved economic efficiency of electric utilities and the provision of better service to energy consumers. These end users are usually connected to the distribution network. Thus, there is a growing research interest in distribution network fault detection and diagnosis algorithms for reducing the down-time due to faults. This is done so as to improve the reliability indices of utility companies and enhance the availability of power supply to customers. The application of signal processing and computational intelligence techniques in power systems protection, automation, and control cannot be overemphasized. This research work focuses on power system distribution network and is aimed at the development of versatile algorithms capable of accurate fault detection and diagnosis of all fault types for operation in balanced/unbalanced distribution networks, under varying fault resistances, fault inception angles, load angles, and system operating conditions. Therefore, different simulation scenarios encompassing various fault types at several locations with different load angles, fault resistances, fault inception angles, capacitor switching, and load switching were applied to the IEEE 34 Node Test Feeder in order to generate the data needed. In particular, the effects of system changes were investigated by integrating various Distributed Generators (DGs) into the distribution feeder. The length of the feeder was also extended and investigations carried out. This was implemented by modelling the IEEE 34-node benchmark test feeder in DIgSILENT PowerFactory (DPF). In the course of this research, a hybrid combination of Discrete Wavelet Transform (DWT), decision-taking rule-based algorithms, and Artificial Neural Networks (ANNs) algorithms for electric power distribution network fault detection and diagnosis was developed. The integrated algorithms were capable of fault detection, fault type classification, identification of the faulty line segment, and fault location respectively. Several scenarios were simulated in the test feeder. The resulting waveforms were exported as ASCII or COMTRADE files to MATLAB for DWT signal processing. Experiments with various DWT mother wavelets were carried out on the waveforms obtained from the simulations. In particular, Daubechies db-2, db-3, db-4, db-5, and db-8 were considered. Others are Coiflet-3 and Symlet-4 mother wavelets respectively. The energy and entropy of the detail coefficients for each decomposition level based on a sampling frequency of 7.68 kHz were analysed. The best decomposition level for the diagnostic tasks was then selected based on the analysis of the wavelet energies and entropy in each level of decomposition. Consequently, level-1 db-4 detail coefficients were selected for the fault detection task, while level-5 db4 detail coefficients were used to compute the wavelet entropy per unit indices which were then used for fault classification, fault section identification, and fault location tasks respectively. Decision-taking rule-based algorithms were used for the fault detection and fault classification tasks respectively. The fault detection task verifies if a fault did indeed occur or not, while the fault classification task determines the fault class and the faulted phase(s). Similarly, Artificial Neural Networks (ANNs) were used for the fault section identification and fault location tasks respectively. For the fault section identification task, the ANNs were trained for pattern classification to identify the lateral or segment affected by the fault. Conversely, the fault location ANNs were trained for function approximation to predict the location of the fault from the substation in kilometres. Also, the IEEE 13 Node Benchmark Test Feeder was modelled in RSCAD software and batch mode simulations were carried out using the Real-Time Digital Simulator (RTDS) as a ‘proof of concept’ for the proposed method, in order to demonstrate the scalability, and to further validate the developed algorithms. The COMTRADE files of disturbance records retrieved from an external IED connected in closed-loop with the RTDS and the runtime simulation waveforms were used as test inputs to the developed Hybrid Fault Detection and Diagnosis (HFDD) method. Comparison of the method based on entropy with statistical methods based on standard deviation and Mean Absolute Deviation (MAD) has shown that the method based on entropy is very reliable, accurate, and robust. Results of preliminary studies carried out showed that the proposed HFDD method can be applied to any power system network irrespective of changes in the operating characteristics. However, certain decision indices would change and the decision-taking rules and ANN algorithms would need to be updated. The HFDD method is promising and would serve as a useful decision support tool for system operators and engineers to aid them in fault diagnosis thereby helping to reduce system down-time and improve the reliability and availability of electric power supply. Key words: Artificial neural network, discrete wavelet transform, distribution network, fault simulation, fault detection and diagnosis, power system protection, RTDS.
Mahajan, Nikhil R. "System Protection for Power Electronic Building Block Based DC Distribution Systems." NCSU, 2004. http://www.lib.ncsu.edu/theses/available/etd-12052004-233822/.
Full text袁綺珊 and Yee-shan Cherry Yuen. "High impedance fault detection and overvoltage protection in low voltage power systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31222146.
Full textYuen, Yee-shan Cherry. "High impedance fault detection and overvoltage protection in low voltage power systems /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20735297.
Full textZhang, Yujie. "Model-based design of a protection scheme for shipboard power systems." Master's thesis, Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-09292008-124423.
Full textChaudhary, Arvind K. S. "Protection system representation in the Electromagnetic Transients Program." Diss., This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-07282008-134541/.
Full textXu, Ran. "Loss of field protection and its impact on power system stability." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/r_xu_120109.pdf.
Full textTitle from PDF title page (viewed on Jan. 28, 2010). "School of Electrical Engineering and Computer Science." Includes bibliographical references (p. 99-101).
Mihirig, Ali Mohamed. "Transient stability analysis of multimachine power systems by catastrophe theory." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/29022.
Full textApplied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
Liang, Feng. "Performance enhancement of digital relays for transmission line distance protection /." Internet access available to MUN users only, 2003. http://collections.mun.ca/u?/theses,153681.
Full textAdewole, Adeyemi Charles. "Voltage stability assessment and wide area protection/control using synchrophasor measurements." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2380.
Full textElectric power systems are being operated closer to their designed stability limits due to the constraints caused by the continuous increase in system loading, and the lack of new power stations and transmission network infrastructure to support this increase in system loading. This coupled with the practice of long distance bulk power transmission and cascading contingencies, makes system instability and consequently blackouts inevitable. In such scenarios, system instabilities like voltage instability becomes a serious threat to the secure operation of the power system, and voltage collapse (system-wide blackouts) are prone to occur. This is often compounded by the unavailability of real-time system measurements for situational awareness from the existing Supervisory Control and Data Acquisition (SCADA)/Energy Management System (EMS) platforms which are usually based on unsynchronized SCADA measurements with a slow reporting rate of 1 measurement every 2-10 seconds. This Doctoral thesis proposes non-iterative algorithms and methods of solution based on the IEEE C37.118 synchrophasor measurements from Phasor Measurement Units (PMUs) with a high reporting rate of up to 200 measurements every second (200 fps) for voltage stability assessment and automated wide area Centralised Protection/Control (CPC) against catastrophic voltage instabilities/blackouts in power systems. Extended formulations are proposed for the Optimal Placement of PMUs (OPP) in power systems with respect to voltage stability assessment. The impact of zero injection buses, critical buses, and PMU redundancy is considered in the formulation of the OPP problem solution. The extended formulations made use of Binary Integer programming (BIP) and Modal Participation Factors (MPFs) derived from the eigenvalues of the power flow Jacobian.
Alanzi, Sultan. "Analysis of a Major Electric Grid – Stability and Adaptive Protection." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1365969976.
Full textLeelaruji, Rujiroj. "Coordination of protection system and VSC-HVDC to mitigate cascading failures." Licentiate thesis, KTH, Electric Power Systems, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-13062.
Full textThe rapid development of the global economics has made power systems allover the world become large-scale interconnected grids. This increases the capabilityof power grids to transfer power over the long distance to serve the desiredpower demand with the minimum cost of operation. Unfortunately, it alsoenables the propagation of local failures into global networks. In other words,if a blackout happens in a power system, the size and the damage may significantlyincrease.
One of the main ways in which blackouts become widespread is cascadingfailures. This type of failure originates after a critical component of the systemhas been removed fromthe service by protective relaying. As a consequence, theload handled by the failed component needs to be redistributed which mightcause an overloading on other components in the system.
On the other hand, the high power electronics controllable devices suchas Voltage Source Converters-based High Voltage Direct Current (VSC-HVDC)transmission are recently developed. These electronics devices have the potentialadvantages such as the ability to independently control active and reactivepower, and maintain voltage to be at acceptable level. Therefore, they are consideredto be the promising devices that with an appropriately designed controlstrategy, they can substantially improve the performance and reliability of thepower system.
This thesis presents the possibility to consider protection system status inthe control of VSC-HVDC link. A great deal of this research is development ofcoordination between this power electronic device and protection system which normally are considered separately. The derivation of protection system has been selected to determine the operation of VSC-HVDC. The methodology isbased on utilizing the signal created from a logical evaluation of relay and simplificationsof certain parameters. By introducing information from the relays tothe VSC-HVDC link via Central Control Unit (CCU), the modulation of transmitted power is devised in order to reduce the risk of system-wide failures. In turn,this means an avoided blackout.Furthermore, this thesis also includes the preliminary suggestion to selectthe location of VSC-HVDC. The methodology is based on predicting voltage instabilityusing voltage stability indices and related parameterswhich are derivedby using Singular ValueDecomposition method. The solutions indicate an effectivelocation for applying corrective action such as load shedding. This optimallocation is selected to reinforce the control strategy of VSC-HVDC in order toprevent cascading failures in the more encompassing systems.
QC20100615
Ramadan, Asmaiel. "Permanent magnet fault current limiters for electrical power protection systems." Thesis, Sheffield Hallam University, 2018. http://shura.shu.ac.uk/22433/.
Full textRatshitanga, Mukovhe. "Investigation and design of an integrated monitoring, protection, and control system of a power reticulation network." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2710.
Full textAs far as substation automation systems are concerned, one of the prime requirements of most utilities today is the interoperability between Intelligent Electronic Devices (IEDs) of different manufacturers. The standard IEC 61850 - Communication Networks and Systems in Substations - allows such interoperability between IEDs for protection and automation of substations. Presently, many manufacturers have implemented, or are in the process of implementing this standard in their IEDs. This has encouraged some utilities to specify IEC is to ensure that both system requirements are met and the features and benefits of the standard are fully exploited. The author of this thesis investigated and brought forward the design of an integrated monitoring protection and control system of a network in Cape Peninsula University of Technology (CPUT) campus based of the IEC 61850 standard. A method of testing the physical IED based on Hardware-In-Loop (HIL) configuration with the Real-Time Digital Simulator (RTDS) is developed and implemented. Mapping of IED Substation Configuration Language (SCL) with that of the RTDS GTNET cards is discussed and implemented to further exploit the use of realtime testing with Generic Object Oriented Substation Event messages (GOOSE). The thesis highlight the benefits of interconnecting the reticulation IEDs into a standardised communication network for protection, control and monitoring of each substation event. This improves the access to information and reduces maintenance cost on the reticulation network.
Yang, Jin. "Fault analysis and protection for wind power generation systems." Thesis, University of Glasgow, 2011. http://theses.gla.ac.uk/2420/.
Full textMercer, Douglas. "Thor's hammer deflected : a history of the protection of power systems from lightning, with special reference to Queensland, 1950 to 1995 /." [St. Lucia, Qld.], 2001. http://adt.library.uq.edu.au/public/adt-QU20020712.164134/index.html.
Full textJanssen, Pierre. "Monitoring, protection and fault location in power distribution networks using system-wide measurements." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209366.
Full textThanks to cost reductions and improvement of information and communication technologies, future distribution networks will probably have advanced communication infrastructures and more measurement devices installed in order to manage the increasing complexity of those networks, which is primarily caused by the introduction of distributed generation at the distribution level.
Therefore this thesis investigates how the monitoring, protection and fault location functions can be improved by using system-wide measurements, i.e. real-time measurements such as synchronized voltage and current measurements recorded at different network locations. Distributed synchronized measurements bring new perspectives for these three functions: protection and fault location are usually performed with local measurements only and synchronized measurements are not common in monitoring applications. For instance, by measuring distributed generators infeed together with some feeder measurements, the protection is expected to be more sensitive and selective and the fault location to be more accurate.
The main contribution of this work is the use of state estimation, which is normally only used for network monitoring, for the protection and the fault location.
The distribution system state estimation is first developed using the classical transmission system approach. The impact of the placement of the measurement devices and of a relatively low measurement redundancy on the accuracy, on the bad data detection and on the topology error identification capabilities of the estimator are discussed and illustrated. This results in recommendations on the placement of the meters.
Then, a backup protection algorithm using system-wide measurements is presented. The coherence of the measurements and the healthy network model are checked thanks to a linear three-phase state estimation. If the model does not fit to the measurements and if the estimated load is too high or unbalanced, a fault is detected. The advantages of the method are that the voltage measurement redundancy is considered, improving the detection sensitivity, and that load models may be considered in the algorithm, avoiding the need to install measurement devices on every line of the network.
Finally, two new impedance-based fault location algorithms using distributed voltage and current recordings are proposed. By defining statistical errors on the measurements and the network parameters, a method to compute a confidence interval of the fault distance estimate is proposed. The fault location accuracy and its sensitivity to the fault conditions (e.g. fault resistance or fault type) and to the different sources of error are assessed on a simulated distribution system.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
Amoda, Oluwaseun Adeyemi. "DEVELOPMENT OF AN ADAPTIVE PROTECTION SCHEME FOR SHIPBOARD POWER SYSTEMS." MSSTATE, 2007. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06062007-133738/.
Full textKim, Mingoo. "Application of computational intelligence to power system vulnerability assessment and adaptive protection using high-speed communication /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/5855.
Full textFerris, Jennifer. "The Design, Implementation, Assessment, and Evaluation of a Power Systems Protection Laboratory Curriculum." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1623.
Full textFarantatos, Evangelos. "A predictive out-of-step protection scheme based on PMU enabled distributed dynamic state estimation." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45863.
Full textAljadid, Abdolmonem Ibrahim. "Control and protection analysis for power distribution in a distributed generation system." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2192.
Full textDistributed Generation systems based on renewable energy sources, such as wind or solar are mostly intermittent sources, due to their dependency on the weather, whereas those based on other primary energy sources are non-intermittent. All of them are specially designed to be integrated into distribution systems, in order to improve the power demand of consumers. In the last few decades of the twentieth century, several different factors have played a key role in increasing interest in systems. Distributed Generation (DG) is gaining more and more attention worldwide as an alternative to large-scale central generating stations. The aim of this research project is to investigate the contribution of distributed generation in fault current level in a power distribution system. The simulation results indicate that DG can have a positive or negative impact, on the fault current level in distribution network systems. The DG location and size affect the fault level. The second aim of this research was to suggest a model-based method for design, and implementation of a protection scheme for power distribution systems, by establish algorithms in a hardware environment. The overcurrent relay was chosen for the model development because it is considered a simple and popular protection scheme, and it is a common scheme in relaying applications. The proposed relay model was tested for fault conditions applied on a simple power system in different scenarios. The overcurrent relay model was implemented in MATLAB/Simulink, by using MATLAB programming languages and the SimPowerSystem (SPS) Tool. MATLAB/SIMULINK software is applicable to the modelling of generation, transmission, distribution and industrial grids, and the analysis of the interactions of these grids. This software provides a library of standard electrical components or models such as transformers, machines, and transmission lines. Therefore, the modelling and simulations are executed using MATLAB/Simulink version 2014b
Gonzalez-Torres, Juan Carlos. "Transient stability of high voltage AC-DC electric transmission systems." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS041.
Full textThe new policy frameworks adopted by national authorities has encouraged the large scale-integration of Renewable Energy Systems (RES) into bulk power systems. The large-scale integration of RES will have consequences on the electricity transmission system as it is conceived today, since the transmission of bulk power over long distances could lead the existing transmission systems to work close to their limits, thus decreasing their dynamic security margins. Therefore more complex transmissions systems are needed.Under this scenario, HVDC transmission systems raise as the most attractive solution for the reinforcement and improvement of existing AC networks, not only using point-to-point configurations, but also in a Multi-Terminal configuration. The introduction of HVDC transmission systems will eventually result in a hybrid high voltage AC/DC power system, which requires to be analyzed as a unique system in order to understand the interactions between the AC network and the DC grid.This thesis addresses the transient stability analysis of hybrid AC/DC electric transmission systems. More in particular, two questions sought to be investigated: What is the impact of a DC contingency on AC transient stability? How can we take advantage of the of DC transmission systems as control inputs in order to enhance AC transient stability?In the first part of this work, the mathematical models of the hybrid AC/DC grid are described as well as the necessary tools for the analysis of the system taking into account its nonlinear nature. Then, a thorough analysis of transient stability of the power system in the particular case of a DC fault and the execution of the corresponding protection strategies is done. As a complement, stability indicators and tools for sizing future MTDC grids in order to respect the constraints of existing protection strategies are proposed.The second part of the thesis addresses the control proposals for the modulation of power references of the HVDC transmission systems with the purpose of transient stability enhancement of the surrounding AC system. Firstly, we focus our study in the nonlinear control of point-to-point HVDC links in hybrid corridors. Fast power compensation, injection of damping power and injection of synchronizing power are identified as the mechanisms through which HVDC systems can improve stability margins.Finally, a control strategy for transient stability enhancement via active power injections of an MTDC grid is proposed. Using communication between the stations, the proposed decentralized control injects damping and synchronizing power between each pair of converters using only measurements at the converters level. The proposed implementation allows to fully use the available headroom of the converters by dealing with power limits in a decentralized way
Salomonsson, Daniel. "Modeling, Control and Protection of Low-Voltage DC Microgrids." Doctoral thesis, Stockholm : Elektriska energisystem, Electric Power Systems, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4666.
Full textVan, der Merwe Neil. "An investigation into the qualities of new and field aged cycloaliphatic epoxide insulation in the Republic of South Africa." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51613.
Full textENGLISH ABSTRACT: The application of cycloaliphatic epoxide (CE) insulation in the Republic of South Africa is investigated within this thesis. There was a request from industry to evaluate the product and indicate its suitability for application within the various geographic and climatic zones typical of the RSA. An extensive survey was conducted into the historic origins of the material, and the experiences of international utilities applying the insulation medium in respect of polluted conditions. The properties of the Automatic Pressure Gelation (APG) CE insulator manufacturing process are discussed with reference to the manufacture of glass and porcelain insulation, and typical areas for concern are discussed with reference to insulators found to deviate from specification. Typical insulators were obtained from the manufacturers and utilities associated with the product, and were subjected to electrical, material and visual examination tests. The electrical tests included AC wet and dry, lightning impulse, clean fog, salt fog, mould release resiliency and the IEC 1109 voltage test. The material tests included the identification of the epoxide systems in use in the RSA, ultraviolet radiation aging simulation, water hydrolysis and salt deposit density tests. The main findings are: • CE insulation is sensitive to marine pollution and continuous-wetting pollution types. • The use of CE insulation is promoted in respect of inland and medium industrial pollution types. • Class B pin-type CE insulation is prone to partial discharge related failures. • Surface roughening on the insulator surfaces leads to reduced AC wet flashover voltages and increased pollution catch. Additionally: • A comprehensive aging hypothesis was developed detailing three independent aging stages/modes applying to CE insulation. • A hypothesis was developed for a new evaluation method for documenting changes on insulator surfaces due to the action of aging mechanisms: The Surface Area Index.
AFRIKAANSE OPSOMMING: Die aanwending van sikloalifatiese epoksied (SE) isolasie in die Republiek Van Suid Afrika word in hierdie skripsie ondersoek. Hierdie ondersoek is geloods op versoek van die elektrisiteitsbedryf om die toepaslike aanwending van die produk onder die verskeie heersende streeksweersomstandighede binne die RSA te evalueer. Breedvoerige navorsing is gedoen om die geskiedkundige oorsprong van die materiaal vas te stel, sowel as om die prestasie daarvan as insulasiemiddel te boekstaaf. Daar is veral gelet op die prestasie van die materiaal onder besoedelende omstandighede en ondervinding wat opgedoen is deur intemasionale ondememings. Die eienskappe van die automatiese drukjelvormings-vervaardigingsproses (APG) word behandel met verwysing na die maak van glas en porselein insulators. Tipiese probleemareas word bespreek van insulators wat afwyk van spesifikasie af. Verteenwoordigende isolators is vanaf vervaardigers en ondememings verkry wat met die produk bemoei is. Hulle is blootgestel aan elektriese, materiaal en visuele toetse. Die elektriese toetse het die volgende behels: nat en droog wisselstroom, skoon waterdamp, sout waterdamp en die IEe 1109 spanningstoets. Die effek van die verlies van die anti-kleefmiddel (gebruik tydens die gietproses) as gevolg van veroudering is ook in detail behandel. Die materiaaltoetse het ingesluit: die uitkenning van die epoksied stelsels in gebruik in die RSA, gesimuleerde veroudering deur ultravioletligbestraling, water hidroliese en soutlaag digtheids toetse. Die hoofbevindings is: • SE isolasie word bemvloed deur seelug besoedeling sowel as volgehoue benatting. Die gebruik van SE isolasie word voorgestel vir binnelandse gebruik sowel as in gebiede met mediumvlak nywerheidsbesoedeling. • Klas B pen-tipe SE isolasie is geneig tot deelontladings wat dan tot faling lei. • Oppervlakvergroffing lei tot In verminderde wisselstroom orvonksspanning onder nat toestande sowel as verhoogde vangs van besoedeling. Bykomend hiertoe is: • 'n breedvoerige SE verouderingshipotese ontwikkel wat drie onafhanklike stadia en modusse van die verouderingsproses uitgewys het. • 'n hipotese ontwikkel vir In nuwe evaluasiemetode om die verandering in die isolatoroppervlak as gevolg van veroudering te dokumenteer: Oppervlakte- Area Indeks (SAl).
Yao, Xiu. "DC Arc Fault Detection and Protection in DC Based Electrical Power Systems." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429857592.
Full textNaidoo, R. M. "A nonlinear adaptive filter for improved operation and protection of power systems." Doctoral thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/5141.
Full textIncludes bibliographical references (leaves 161-171).
This thesis presents the application of a nonlinear adaptive filter to selected areas in power systems. The filter has demonstrated excellent performance against con-ventional methods in biomedical applications. The algorithm is robust in structure and highly immune to noise. Applications in this thesis include (1) sag detection, (2) symmetrical component estimation, (3) phase and frequency estimation, (4) sag analysis and (5) distributed generation synchronisation and protection. The appli-cations were chosen such that the amplitude, phase and frequency tracking ability are thoroughly tested.
Girouard, Pierre. "Un système expert pour la gestion en temps réel des alarmes dans un réseau électrique /." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63940.
Full textGuan, Rui. "Stability control and protection of power systems with VSC HVDC and VSC FACTS." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8639/.
Full textMeadowcroft, Brian K. "Hidden Failures in Shipboard Electrical Integrated Propulsion Plants." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/42754.
Full textMaster of Science
Mohammadi, Houshang C. "Short-circuit current calculations and protective relay coordination for industrial and commercial power systems." Ohio : Ohio University, 1986. http://www.ohiolink.edu/etd/view.cgi?ohiou1183141301.
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