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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The protection of transmission networks containing AC and DC circuits

Wang, Hualei January 2015 (has links)
In 14th August 2003, the Northeast USA suffered its worst power outage event in history. The power disturbance spreading through the system caused mal-trips of the distance relay remote back-up protections, which indeed contributed to the power outage cascading a wide area. The power outage in the Northeast USA was constrained by the presence of HVDC interconnections between the HVAC networks in Ontario and New York. The system collapse did not progress beyond the HVDC interconnection interface with Quebec. The HVDC link can regulate the voltage and current therefore impacts on the performance of the protection and system stability. The distance relay mal-operations were one of the main cause of the Northeast USA blackout as well as the other recent major large area blackouts which were pointed out by the previous papers. This thesis is focus on investigate how HVDC interconnections contribute to maintaining the power system stability. The research work investigated the performance of a distance relay to faults and disturbance on networks containing HVDC interconnection. The research work was carried out by modelling and testing a classic signal processing distance relay in a simple AC network which was based on Kunder’s two areas system using MATLAB/SIMULINK at first. Then the modeled distance relay’s performance was investigated by combining the distance relay and a simple HVDC link based on the Kunder’s two areas system. The research work firstly combined the signal processing distance relay and the HVDC link together to investigate the distance relay’s performance when the protected feeder containing DC link. The distance relay’s performance was investigated when the protected feeders containing HVDC link under fault conditions and power swing conditions. For comparison, a similar power system without HVDC link was also simulated.
2

Design and implementation of ANN based phase comparators applied to transmission line protection

Chawla, Gaganpreet 24 February 2010
There has been significant development in the area of neural network based power system protection in the previous decade. Neural network technology has been applied for various protective relaying functions including distance protection. The reliability and efficiency of ANN based distance relays is improving with the developing digital technologies. There are, however, some inherent deficiencies that still exist in the way these relays are designed. This research addresses some of these issues and proposes an improved protective relaying scheme.<p> The traditional ANN distance relay designs use parameter estimation algorithms to determine the phasors of currents and voltages. These phasors are used as inputs to determine the distance of a fault from relay location. The relays are trained and tested on this criterion; however, no specific relay characteristic has been defined. There is a need for development of a new methodology that will enable designing of an ANN that works as a generic distance relay with clearly defined operating boundary.<p> This research work presents a modified distance relaying algorithm that has been combined with a neural network approach to eliminate the use of phasors. The neural network is trained to recognize faults on basis of a specific relay characteristic. The algorithm is flexible and has been extended for the design of other relays. The neural network has been trained using pure sinusoidal values and has been tested on a 17-bus power system simulated in PSCAD. The training and testing of the neural network on different systems ensures that the relay is generic in nature. The proposed relay can be used on any transmission line without re-training the neural network.<p> The design has been tested for different fault conditions including different fault resistances and fault inception angles. The test results show that the relay is able to detect faults in lesser time as compared to conventional relay algorithms while maintaining the integrity of relay boundaries.
3

Design and implementation of ANN based phase comparators applied to transmission line protection

Chawla, Gaganpreet 24 February 2010 (has links)
There has been significant development in the area of neural network based power system protection in the previous decade. Neural network technology has been applied for various protective relaying functions including distance protection. The reliability and efficiency of ANN based distance relays is improving with the developing digital technologies. There are, however, some inherent deficiencies that still exist in the way these relays are designed. This research addresses some of these issues and proposes an improved protective relaying scheme.<p> The traditional ANN distance relay designs use parameter estimation algorithms to determine the phasors of currents and voltages. These phasors are used as inputs to determine the distance of a fault from relay location. The relays are trained and tested on this criterion; however, no specific relay characteristic has been defined. There is a need for development of a new methodology that will enable designing of an ANN that works as a generic distance relay with clearly defined operating boundary.<p> This research work presents a modified distance relaying algorithm that has been combined with a neural network approach to eliminate the use of phasors. The neural network is trained to recognize faults on basis of a specific relay characteristic. The algorithm is flexible and has been extended for the design of other relays. The neural network has been trained using pure sinusoidal values and has been tested on a 17-bus power system simulated in PSCAD. The training and testing of the neural network on different systems ensures that the relay is generic in nature. The proposed relay can be used on any transmission line without re-training the neural network.<p> The design has been tested for different fault conditions including different fault resistances and fault inception angles. The test results show that the relay is able to detect faults in lesser time as compared to conventional relay algorithms while maintaining the integrity of relay boundaries.
4

Relé digital de distância baseado na teoria de ondas viajantes e transformada Wavelet / Positional protection using travelingw waves and Wavelet transform theory

Valins, Thiago Ferreira 14 January 2005 (has links)
Neste trabalho, será abordada a proteção digital fundamentada na teoria de ondas viajantes e da ferramenta Transformada Wavelet. Um algoritmo completo para proteção digital foi implementado, consistindo basicamente nos módulos de detecção, classificação e localização da falta, com a conseqüente determinação das zonas de proteção do relé. Para este esquema completo de releamento, empregou-se como ferramenta de análise a Transformada Wavelet. Sinais transitórios de alta freqüência gerados por uma situação de falta podem ser analisados pela Transformada Wavelet, detectando-se com precisão o instante de chegada das ondas em um ou nos dois terminais da linha. Conhecendo o instante de chegada dessas ondas e sua velocidade de propagação, a zona de proteção na qual a falta está alocada pode ser estimada de maneira fácil e rápida. A capacidade de acusar com precisão os instantes de chegada das ondas torna a Transformada Wavelet adequada ao problema de determinação das zonas de proteção. Nessa implementação, o usuário pode escolher entre as técnicas de aquisição de dados provenientes de um ou de dois terminais. O algoritmo foi implementado através do software Matlabâ e posteriormente testado, quando se utilizaram dados de faltas obtidos através de simulações no software ATP (Alternative Transients Program). Nas simulações aplicadas a este software, considerou-se um sistema de transmissão de 440 kV. As simulações produziram uma base de dados, variando-se os seguintes parâmetros: tipos de faltas, localizações ao longo da linha, ângulos de incidência, resistências de faltas, entre outros. Pelos resultados alcançados, pode-se afirmar que a aplicação é bastante adequada para uso em relés digitais de distância. / The present work deals with digital protection based on the traveling wave theory and Wavelet transform. An complete algorithm for digital protection was implemented. It is composed of modules of fault detection, classification, location, with protection zone determination. For this complete relaying scheme the Wavelet transform was employed as analysis tool. Transient signals of high frequency generated by the fault occurrence was analyzed by the Wavelet transform, and also the instant of the waves arrival was accurately detected in one or two terminals of the line. By knowing the instant of the arrival of the waves and their propagation velocity, the protection zone, in which the fault is located, can be estimated easily and quickly. The Wavelet transform property of accurate detection the instant of waves arrival make it appropriate to the problem of protection zone determination. In this implementation, the user can choose between the location techniques using data from one or two terminals. The algorithm was implemented by Matlab® software and then tested utilizing data of faults obtained by means of simulations of ATP software (Alternative Transients Program). In these simulations, a transmission line of 440 kV was considered. These simulations produced a database composed of various fault types considering different fault locations, fault inception angles and fault resistances. According to the analysis of the test results, it is possible to verify that the application is very adequate for use in digital distance relays.
5

Relé digital de distância baseado na teoria de ondas viajantes e transformada Wavelet / Positional protection using travelingw waves and Wavelet transform theory

Thiago Ferreira Valins 14 January 2005 (has links)
Neste trabalho, será abordada a proteção digital fundamentada na teoria de ondas viajantes e da ferramenta Transformada Wavelet. Um algoritmo completo para proteção digital foi implementado, consistindo basicamente nos módulos de detecção, classificação e localização da falta, com a conseqüente determinação das zonas de proteção do relé. Para este esquema completo de releamento, empregou-se como ferramenta de análise a Transformada Wavelet. Sinais transitórios de alta freqüência gerados por uma situação de falta podem ser analisados pela Transformada Wavelet, detectando-se com precisão o instante de chegada das ondas em um ou nos dois terminais da linha. Conhecendo o instante de chegada dessas ondas e sua velocidade de propagação, a zona de proteção na qual a falta está alocada pode ser estimada de maneira fácil e rápida. A capacidade de acusar com precisão os instantes de chegada das ondas torna a Transformada Wavelet adequada ao problema de determinação das zonas de proteção. Nessa implementação, o usuário pode escolher entre as técnicas de aquisição de dados provenientes de um ou de dois terminais. O algoritmo foi implementado através do software Matlabâ e posteriormente testado, quando se utilizaram dados de faltas obtidos através de simulações no software ATP (Alternative Transients Program). Nas simulações aplicadas a este software, considerou-se um sistema de transmissão de 440 kV. As simulações produziram uma base de dados, variando-se os seguintes parâmetros: tipos de faltas, localizações ao longo da linha, ângulos de incidência, resistências de faltas, entre outros. Pelos resultados alcançados, pode-se afirmar que a aplicação é bastante adequada para uso em relés digitais de distância. / The present work deals with digital protection based on the traveling wave theory and Wavelet transform. An complete algorithm for digital protection was implemented. It is composed of modules of fault detection, classification, location, with protection zone determination. For this complete relaying scheme the Wavelet transform was employed as analysis tool. Transient signals of high frequency generated by the fault occurrence was analyzed by the Wavelet transform, and also the instant of the waves arrival was accurately detected in one or two terminals of the line. By knowing the instant of the arrival of the waves and their propagation velocity, the protection zone, in which the fault is located, can be estimated easily and quickly. The Wavelet transform property of accurate detection the instant of waves arrival make it appropriate to the problem of protection zone determination. In this implementation, the user can choose between the location techniques using data from one or two terminals. The algorithm was implemented by Matlab® software and then tested utilizing data of faults obtained by means of simulations of ATP software (Alternative Transients Program). In these simulations, a transmission line of 440 kV was considered. These simulations produced a database composed of various fault types considering different fault locations, fault inception angles and fault resistances. According to the analysis of the test results, it is possible to verify that the application is very adequate for use in digital distance relays.
6

Um novo método de estimação fasorial para uso em relés digitais de proteção.

CAMPOS, Alana Kelly Xavier Santos. 04 May 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-05-04T19:00:50Z No. of bitstreams: 1 ALANA KELLY XAVIER SANTOS CAMPOS – TESE (PPGEE) 2016.pdf: 5517354 bytes, checksum: 24306600f8b9a28a2d230c48b0811a3a (MD5) / Made available in DSpace on 2018-05-04T19:00:50Z (GMT). No. of bitstreams: 1 ALANA KELLY XAVIER SANTOS CAMPOS – TESE (PPGEE) 2016.pdf: 5517354 bytes, checksum: 24306600f8b9a28a2d230c48b0811a3a (MD5) Previous issue date: 2016-10-21 / Capes / Um método de estimação fasorial é proposto para ser utilizado em relés digitais de proteção. Este método tem o objetivo de melhorar a característica de rejeição de componentes indesejáveis do sinal, que são introduzidas durante faltas e manobras nos sistemas elétricos de potência e podem comprometer o desempenho dos sistemas de proteção. São realizadas comparações entre o método proposto e outros quatro métodos de estimação fasorial, em relação às respostas no tempo e frequência. Para as comparações de resposta no tempo são utilizados sinais analíticos provenientes do MATrix LABoratory (MATLAB®) e sinais simulados provenientes do Alternative Transients Program (ATP). Um relé de distância foi implementado utilizando a linguagem MODELS do ATP para avaliar o desempenho do relé, utilizando o método proposto e demais métodos avaliados. A partir de alguns parâmetros usados para avaliar quantitativamente os métodos de estimação, observou-se que o método proposto apresenta bons resultados em termos de precisão e velocidade de convergência, com resposta no tempo compatível com os demais métodos comumente utilizados. A resposta em frequência do método proposto se apresenta mais seletiva em relação aos demais, por apresentar menores lóbulos entre as harmônicas e uma banda de passagem mais estreita em torno da frequência fundamental. Outra vantagem do método proposto é que ele é de fácil programação e permite que os usuários alterem parâmetros de projeto de acordo com suas necessidades. / A phasor estimation method is proposed to be used in digital relays for power system protection. It aims to improve the characteristic of filtering out undesirable frequency components of signals, which are introduced during faults and switching events in electric power systems that may compromise the performance of the protection systems. Comparisons are made in relation to time response and frequency response for the proposed method and four phasor estimation methods. In relation to response time are used analytical signals from MATrix LABoratory (MATLAB®) and simulated signals from Alternative Transients Program (ATP). A distance relay was implemented by using the MODELS language in ATP to evaluate the performance of the relay. From some parameters used to evaluate the estimation methods, it was observed that the proposed method shows good results in terms of accuracy and convergence speed, with response time compatible with other methods. The frequency response of the proposed method appears to be more selective than those of the others methods because it presents lower lobes between the harmonics and a narrower pass band around the fundamental frequency. Another advantage of the proposed method is that it can be easily programmed, allowing users to change design parameters according to their needs.
7

Metodologia para coordenação otimizada entre relés de distância e direcionais de sobrecorrente em sistemas de transmissão de energia elétrica / Methodology for optimized coordination of distance and directional overcurrent relays in electrical transmission systems

Moro, Vinícius de Cillo 05 September 2014 (has links)
A proteção de sistemas de energia elétrica possui papel extremamente importante no aspecto de garantir o fornecimento de energia de maneira segura e confiável. Assim, a ação indevida ou a não atuação deste sistema de proteção pode causar danos materiais ou econômicos tanto para as concessionárias quanto para os consumidores de energia elétrica. Dessa forma, o sistema de proteção deve estar bem ajustado para que possa garantir suas funções, sendo sensível, seletivo, confiável e rápido. Para tanto, uma boa coordenação entre os relés de proteção deve ser estabelecida. No caso de um sistema de transmissão, o qual costuma ser um sistema malhado, a proteção é comumente realizada por relés de distância aliados a relés de sobrecorrente com unidade direcional, sendo que estes funcionam como elemento de retaguarda daqueles. O processo de ajuste desses relés é um trabalho muito difícil e demorado, que pode ainda estar sujeito a erros do engenheiro de proteção responsável pelo estudo. Neste contexto, este trabalho tem como objetivo desenvolver uma metodologia baseada na otimização por enxame de partículas que obtenha automaticamente os ajustes desses relés de forma a garantir a coordenação e seletividade entre eles, tornando assim o processo de ajuste mais rápido e preciso. Dessa forma, essa metodologia pode constituir uma ferramenta de auxílio muito favorável ao engenheiro de proteção. Além disso, como em todo problema de otimização, a função objetivo e as restrições foram definidas de maneira a retratar o problema de coordenação envolvendo tanto os relés de distância quanto os direcionais de sobrecorrente. A metodologia foi aplicada a dois sistemas, um fictício com 16 relés e um sistema de transmissão real com 44 relés, sendo que em ambos os casos ela apresentou resultados bastante satisfatórios proporcionando ajustes bem coordenados. / Electrical power systems protection has a very important role in the aspect of ensuring energy supply with safety and reliability. Thus, improper action or non-actuation of this protection system can cause materials and/or economics damages to electricity utilities as well as ordinary energy consumers. Therefore the protection system must be well adjusted so it can ensure its functions and thus being sensible, selective, reliable and fast. In order to achieve these characteristics, the protective relays must be well coordinated. In the case of meshed transmission systems, the protection is generally performed by distance relays as primary protection associated with directional overcurrent relays as backup protection. The process of adjusting these relays is very tough, slow and it can even be subject to the protection engineer mistakes. In this context, this work aims to develop a particle swarm optimization based methodology that can automatically obtain these relays adjusts so they can ensure relays coordination and selectivity, and then make this setting process faster and more precise. Thus, this methodology may provide a very favorable tool to aid the protection engineer. Moreover, as in any optimization problem, the objective function and the constraints were defined to represent the coordination problem involving both distance and directional overcurrent relays. The methodology was applied to two systems, a fictitious with 16 relays and a real transmission system with 44 relays, and in both cases it showed satisfactory results providing well-coordinated settings.
8

Metodologia para coordenação otimizada entre relés de distância e direcionais de sobrecorrente em sistemas de transmissão de energia elétrica / Methodology for optimized coordination of distance and directional overcurrent relays in electrical transmission systems

Vinícius de Cillo Moro 05 September 2014 (has links)
A proteção de sistemas de energia elétrica possui papel extremamente importante no aspecto de garantir o fornecimento de energia de maneira segura e confiável. Assim, a ação indevida ou a não atuação deste sistema de proteção pode causar danos materiais ou econômicos tanto para as concessionárias quanto para os consumidores de energia elétrica. Dessa forma, o sistema de proteção deve estar bem ajustado para que possa garantir suas funções, sendo sensível, seletivo, confiável e rápido. Para tanto, uma boa coordenação entre os relés de proteção deve ser estabelecida. No caso de um sistema de transmissão, o qual costuma ser um sistema malhado, a proteção é comumente realizada por relés de distância aliados a relés de sobrecorrente com unidade direcional, sendo que estes funcionam como elemento de retaguarda daqueles. O processo de ajuste desses relés é um trabalho muito difícil e demorado, que pode ainda estar sujeito a erros do engenheiro de proteção responsável pelo estudo. Neste contexto, este trabalho tem como objetivo desenvolver uma metodologia baseada na otimização por enxame de partículas que obtenha automaticamente os ajustes desses relés de forma a garantir a coordenação e seletividade entre eles, tornando assim o processo de ajuste mais rápido e preciso. Dessa forma, essa metodologia pode constituir uma ferramenta de auxílio muito favorável ao engenheiro de proteção. Além disso, como em todo problema de otimização, a função objetivo e as restrições foram definidas de maneira a retratar o problema de coordenação envolvendo tanto os relés de distância quanto os direcionais de sobrecorrente. A metodologia foi aplicada a dois sistemas, um fictício com 16 relés e um sistema de transmissão real com 44 relés, sendo que em ambos os casos ela apresentou resultados bastante satisfatórios proporcionando ajustes bem coordenados. / Electrical power systems protection has a very important role in the aspect of ensuring energy supply with safety and reliability. Thus, improper action or non-actuation of this protection system can cause materials and/or economics damages to electricity utilities as well as ordinary energy consumers. Therefore the protection system must be well adjusted so it can ensure its functions and thus being sensible, selective, reliable and fast. In order to achieve these characteristics, the protective relays must be well coordinated. In the case of meshed transmission systems, the protection is generally performed by distance relays as primary protection associated with directional overcurrent relays as backup protection. The process of adjusting these relays is very tough, slow and it can even be subject to the protection engineer mistakes. In this context, this work aims to develop a particle swarm optimization based methodology that can automatically obtain these relays adjusts so they can ensure relays coordination and selectivity, and then make this setting process faster and more precise. Thus, this methodology may provide a very favorable tool to aid the protection engineer. Moreover, as in any optimization problem, the objective function and the constraints were defined to represent the coordination problem involving both distance and directional overcurrent relays. The methodology was applied to two systems, a fictitious with 16 relays and a real transmission system with 44 relays, and in both cases it showed satisfactory results providing well-coordinated settings.
9

Intelligent Systems Applications For Improving Power Systems Security

Bhimasingu, Ravikumar 07 1900 (has links)
Electric power systems are among the most complex man made systems on the world. Most of the time, they operate under quasi-steady state. With the ever increasing load demand and the advent of the deregulated power market recently, the power systems are pushed more often to operate close to their design limits and with more uncertainty of the system operating mode. With the increasing complexity and more interconnected systems, power systems are operating closer to their performance limits. As a result, maintaining system security and facilitating efficient system operation have been challenging tasks. Transmission systems are considered the most vital components in power systems connecting both generating/substation and consumer areas with several interconnected networks. In the past, they were owned by regulated, vertically integrated utility companies. They have been designed and operated so that conditions in close proximity to security boundaries are not frequently encountered. However, in the new open access environment, operating conditions tend to be much closer to security boundaries, as transmission use is increasing in sudden and unpredictable directions. Transmission unbundling, coupled with other regulatory requirements, has made new transmission facility construction more difficult. Unfortunately these transmission lines are frequently subjected to a wide variety of faults. Thus, providing proper protective functions for them is essential. Generally the protection of Extra High Voltage (EHV) and Ultra High Voltage (UHV) transmission lines are carried out by the use of distance relays in view of the fact that they provide fast fault clearance and system coordination. Transmission line relaying involves detection, classification and location of transmission line faults. Fast detections of faults enable quick isolation of the faulty line from service and hence, protecting it from the harmful effects of fault. Classification of faults means identification of the type of fault and faulted line section, and this information is required for finding the fault location and assessing the extent of repair work to be carried out. Accurate fault location is necessary for facilitating quick repair and restoration of the line, to improve the reliability and availability of the power supply. Generally, the protection system using conventional distance relaying algorithm involves three zones. The first zone (Z1) of the relay is set to detect faults on 80%90% of the protected line without any intentional time delay. The second zone (Z2) is set to protect the remainder of the line plus an adequate margin. Second zone relays are time delayed for 1530 cycles to coordinate with relays at remote bus. The settings of the third zone (Z3) ideally will cover the protected line, plus all of the longest line leaving the remote station. Z3 of a distance relay is used to provide the remote backup protection in case of the failure of the primary protection. Since Z3 covers an adjacent line, a large infeed (outfeed) from the remote terminal causes the relay to underreach (overreach). Thus, a very large load at the remote terminal may cause distance relays to mal-operate. Settings for conventional distance relays are selected to avoid overreach/underreach operation under the worst case scenarios. Studies of significant power system disturbances reported by North American Electric Reliability Council (NERC) indicate that protective relays are involved, one way or another, in 75% of the major disturbances and the most troublesome ones are backup protection relays. With their limited view of the interconnected network based on their locally measured inputs, conventional backup protection relays generally take actions to protect a localized region of the network without considering the impact on the whole network. Relay mal-operations or unintended operations due to overload, power swing, and relay hidden failure are the main factors contributing to the blackouts. Most of the problems are associated with relays tripping too many healthy lines. Since a relay makes the decision automatically to remove a component from the system according to its internal mechanism, the relay mal-operation or unintended operation can make an effective influence on the system stability. Approaches to reduce the relay misbehavior need to be identified. Real time monitoring tools to assess the relay misbehavior are needed, providing the system operator, the accurate information about unfolding events. Existing transmission line protection scheme still has drawbacks. Advanced fault analysis mechanism to enhance the system dependability and security simultaneously is desirable. Relay settings play a significant role in major blackouts. So correct settings should be calculated and coordinated by suitable studies. Attempts are to be made to employ highly accurate AI techniques in protective system implementation. The research work focussed on developing knowledge based intelligent tools for the improving the transmission system security. A process to obtain knowledgebase using SVMs for ready post-fault diagnosis purpose is developed. SVMs are used as Intelligent tool for identifying the faulted line that is emanating from a substation and finding the distance from the substation. The approach uses phasor values of the line voltages and currents after the fault has been detected. The approach is particularly important for post-fault diagnosis of any mal-operation of relays following a disturbance in the neighboring line connected to the same substation. This may help in improving the fault monitoring/diagnosis process and coordination of the protective relays, thus assuring secure operation of the power systems. The approach based on SVMs, exploits the first part of this goal. For comparison, a classifier and regression tools based on the RBFNNs was also investigated. The RBFNNs and SVM networks are introduced and considered as an appropriate tool for pattern recognition problems. Results on a practical 24Bus equivalent EHV transmission system of Indian Southern region and on IEEE39 bus New England system are presented to illustrate the proposed method. In a large connected power network, the number of generators are more in number and their set patterns number will be large. As the line flows are sensitive to generator set patterns, it is difficult to consider all the combinations of generators while simulating the training and testing patterns as input to SVMs. To simulate the training and testing patterns corresponding to possible changes in line flows to meet the load in the present deregulated environment, line flow sensitive generators set to be identified/merit-listed. In this regard, to identify the most sensitive generators for a particular line of interest, a method from the literature is adopted and developed a software program based on the graph theory concepts. Case studies on generator contributions towards loads and transmission lines are illustrated on an equivalent 33bus system, a part of Indian Northern grid with major part of Uttar Pradesh and also with an equivalent 246bus system of practical Indian Southern grid. A distance relay coordination approach is proposed using detailed simulation studies, taking into account various operating conditions and fault resistances. Support Vector Machines as a pattern classifier is used for obtaining distance relay coordination. The scheme uses the apparent impedance values observed during fault as inputs. SVMs are used to build the underlying concept between reach of different zones and the impedance trajectory during fault. An improved performance with the use of SVMs, keeping the reach when faced with different fault conditions as well as line flow changes are illustrated with an equivalent 246bus system of practical Indian Southern grid and also with an equivalent 265bus system of practical Indian Western grid. A strategy of Supportive System is described to aid the conventional protection philosophy in combating situations where protection systems are mal-operated and/or information is missing and provide selective and secure coordination. Highly accurate identification/discrimination of zones plays a key role in effective implementation of the region-wide supportive system. This typically requires a multiclass SVM classifier to effectively analyze/build the underlying concept between reach of different zones and the apparent impedance trajectory during fault. Different multiclass methods are compared for their performance with respect to accuracy, number of iterations, number of support vectors, training and testing time. The performance analysis of these methods is presented on three data sets belonging to the training and testing patterns of three supportive systems for a region, part of a network, which is an equivalent 265bus system of practical Indian Western grid.
10

Análise de proteção de linhas de transmissão através de relés numéricos e uso de models externos no ATP (Alternative Transient Program) /

Fabián Espinoza, Renzo Grover. January 2011 (has links)
Orientador: Jose Roberto Sanches Mantovani / Banca: Luiz Fernando Bovolato / Banca: Rodrigo Aparecido Fernandes Pereira / Resumo: Neste trabalho apresenta-se uma metodologia para obter um ambiente interativo de simulação com ferramentas que permitam fazer análises de sistemas de proteção como estudos de coordenação e analises pós falta. As ferramentas estão baseadas no programa de simulação de transitórios eletro- magnéticos EMTP/ATP e na linguagem de programação ANSI C, sobre a plataforma de software livre GNU/Linux. Esta metodologia pode ser implementada, da mesma forma, em qualquer plataforma Windows sobre a qual possa funcionar o EMTP/ATP e o pacote ATP/MingW. Assim, implementou- se um relé de distância numérico através de modelos externos ("foreign models"). Ilustra-se também como usar arquivos no formato COMTRADE na análise com EMTP/ATP. Dessa forma foi possível analisar o comportamento do relé implementado tendo como entradas os sinais de tensões e correntes correspondentes aos eventos reais. Os sinais de disparo, assim como os demais componentes do relé, foram testados usando um sistema teste de referência do Power System Relaying Committee da PES-IEEE e os sinais de faltas reais do Sistema Elétrico Interligado da Colômbia. Por fim, foi feito um estudo de coordenação. Os resultados são apresentados e discutidos. A metodologia proposta pode ser usada para desenvolver qualquer componente ou elemento de controle dentro de um sistema elétrico, onde haja a necessidade de usar o EMTP/ATP para simular condições específicas de operação do sistema elétrico, complementando a simplicidade da linguagem MODELS com a portabilidade e potencialidade da linguagem C / Abstract: This work presents the methodology to obtain an environment of interactive simulation with tools to perform analysis of protection systems, coordination studies and analysis post fault. These tools are based on the program for electromagnetic transients EMTP/ATP and in ANSI C programming language used in the free GNU/Linux software platform. The same methodology can be followed to be used on any Windows Operating System that can run EMTP/ATP and the package ATP/MingW. Then, for this, a numerical distance relay was implemented by means of foreign models using C programming language. It also shows how to use COMTRADE files in analysis with EMTP / ATP. Thus it was possible to analyze the behavior of the implemented relay with voltage and current signals of real events as inputs. The trip signals, like the other components of the relay, were tested using a testing reference system of Power System Relaying Committee of PES-IEEE and the signals of real faults of Inter- connected Electric System of Colombia. Finally, a coordination study was made. The results are presented and discussed. This methodology could also be used to develop any component or control element within an electrical system that one may need for a particular use; therefore, compensating the simplicity of the language MODELS with the flexibility and portability of C programming language / Mestre

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