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Este trabalho tem como objetivo apresentar conceitos e prover ferramentas para estudos e análises de um equipamento ainda não explorado pelo sistema elétrico brasileiro para compensação reativa de linhas de transmissão, o Reator Controlado por Saturação. Inicialmente é apresentada a teoria necessária para o entendimento do equipamento, as aplicações e sua potencial utilidade para o Brasil. Através da concepção de um circuito equivalente e da análise de modelos adaptados para o MCSR (Magnetic Controlled Shunt Reactors) de softwares de transitórios eletromagnéticos aspectos sobre seu comportamento dinâmico e tempo de resposta são esclarecidos. Uma comparação entre o circuito equivalente com um modelo generalista de transformador ajustado às características do MCSR é realizada. A comparação serve para conferir credibilidade às suposições usadas para a elaboração do circuito equivalente e interpretações do funcionamento e dinâmica extraídas da análise deste circuito. Com uma melhor e mais clara percepção da dinâmica e efeitos do Reator Controlado por Saturação sobre a rede, realiza-se uma análise de distorção harmônica, sendo assim possível esclarecer alguns aspectos negativos do equipamento. Para o estudo da aplicabilidade e utilidade do MCSR no sistema elétrico brasileiro um modelo para transitórios eletromecânicos é proposto. Os parâmetros que determinam a dinâmica e resposta do equipamento são explorados através de suposições razoáveis e das características do equipamento. O modelo é primeiramente testado e analisado em um sistema simples composto por uma geração representada como fonte ideal, um circuito equivalente PI de uma linha de transmissão, uma carga e o MCSR realizando a compensação reativa. O trabalho segue para a escolha de uma rede brasileira em que o MCSR seria uma opção viável. Uma rede no norte do Brasil é escolhida para a análise e, após estudos de fluxo de potência, propõe-se a troca de um CER (Compensador Estático de Reativos) e quatro reatores shunt fixos por quatro Reatores Controlados por Saturação. A rede é então modelada no PSCAD e realizam-se estudos de distorção harmônica e estabilidade eletromecânica. Por fim realiza-se uma comparação econômica entre três alternativas de compensação reativa para o sistema escolhido incluindo a opção adotada e a opção sugerida com MCSRs. O trabalho conclui que reatores controlados por saturação são, em muitos casos, uma alternativa mais barata ao CER e, portanto deve ser estudado no planejamento e expansão do sistema elétrico. / This work aims to present concepts and provide tools for research and analysis of an equipment not yet explored by the Brazilian power system for reactive compensation of AC transmission lines, the Magnetic Controlled Shunt Reactor (MCSR). Initially, the theory used for the understanding of the equipment, its applications and usefulness for the Brazilian network, is presented. By the analysis of an equivalent circuit and a model implemented in software for electromagnetic transient simulation adapted to the MCSR (Magnetic Controlled Shunt Reactors) some aspects of its dynamic behaviour and response time are clarified. A comparison between the equivalent circuit and an electromagnetic transformer model adapted to the characteristics of the MCSR (implemented in the PSCAD software) is performed. The comparison serves to grant credibility to the assumptions used for the preparation of the equivalent circuit and interpretations of the function and dynamics drawn from the analysis of this circuit. With a better and clearer understanding of the dynamics and effects of the MCSR on the network a simplified analysis of harmonic distortion is performed allowing to clarify some negative aspects of the equipment. To study the applicability and usefulness of the equipment in the Brazilian electrical system a model for electromechanical transients is proposed. The parameters that determine the dynamics and response of equipment are explored using reasonable assumptions and the characteristics of the equipment. The model is first tested and analyzed in a simplified system consisting of a generation represented as ideal source, an equivalent PI circuit representing a transmission line, a load and the MCSR performing the reactive compensation. The work follows to the choice of a Brazilian network on which the MCSR would be a viable option. A network in northern Brazil is chosen for analysis. Further studies of power flow reveals the possibility to exchange the SVS (Static Var System ) and four shunt reactors for four MCSRs. The network is then modelled in PSCAD and studies of harmonic distortion and electromechanical stability are conducted. Finally we make an economic comparison between three alternatives of reactive compensation for the chosen system including the originally adopted and the suggested solutions. The study concludes that magnetic controlled reactor are, in many cases, a cheaper alternative to the SVS and therefore should be studied in the planning and expansion of the power system.

Este trabalho tem como objetivo apresentar conceitos e prover ferramentas para estudos e análises de um equipamento ainda não explorado pelo sistema elétrico brasileiro para compensação reativa de linhas de transmissão, o Reator Controlado por Saturação. Inicialmente é apresentada a teoria necessária para o entendimento do equipamento, as aplicações e sua potencial utilidade para o Brasil. Através da concepção de um circuito equivalente e da análise de modelos adaptados para o MCSR (Magnetic Controlled Shunt Reactors) de softwares de transitórios eletromagnéticos aspectos sobre seu comportamento dinâmico e tempo de resposta são esclarecidos. Uma comparação entre o circuito equivalente com um modelo generalista de transformador ajustado às características do MCSR é realizada. A comparação serve para conferir credibilidade às suposições usadas para a elaboração do circuito equivalente e interpretações do funcionamento e dinâmica extraídas da análise deste circuito. Com uma melhor e mais clara percepção da dinâmica e efeitos do Reator Controlado por Saturação sobre a rede, realiza-se uma análise de distorção harmônica, sendo assim possível esclarecer alguns aspectos negativos do equipamento. Para o estudo da aplicabilidade e utilidade do MCSR no sistema elétrico brasileiro um modelo para transitórios eletromecânicos é proposto. Os parâmetros que determinam a dinâmica e resposta do equipamento são explorados através de suposições razoáveis e das características do equipamento. O modelo é primeiramente testado e analisado em um sistema simples composto por uma geração representada como fonte ideal, um circuito equivalente PI de uma linha de transmissão, uma carga e o MCSR realizando a compensação reativa. O trabalho segue para a escolha de uma rede brasileira em que o MCSR seria uma opção viável. Uma rede no norte do Brasil é escolhida para a análise e, após estudos de fluxo de potência, propõe-se a troca de um CER (Compensador Estático de Reativos) e quatro reatores shunt fixos por quatro Reatores Controlados por Saturação. A rede é então modelada no PSCAD e realizam-se estudos de distorção harmônica e estabilidade eletromecânica. Por fim realiza-se uma comparação econômica entre três alternativas de compensação reativa para o sistema escolhido incluindo a opção adotada e a opção sugerida com MCSRs. O trabalho conclui que reatores controlados por saturação são, em muitos casos, uma alternativa mais barata ao CER e, portanto deve ser estudado no planejamento e expansão do sistema elétrico. / This work aims to present concepts and provide tools for research and analysis of an equipment not yet explored by the Brazilian power system for reactive compensation of AC transmission lines, the Magnetic Controlled Shunt Reactor (MCSR). Initially, the theory used for the understanding of the equipment, its applications and usefulness for the Brazilian network, is presented. By the analysis of an equivalent circuit and a model implemented in software for electromagnetic transient simulation adapted to the MCSR (Magnetic Controlled Shunt Reactors) some aspects of its dynamic behaviour and response time are clarified. A comparison between the equivalent circuit and an electromagnetic transformer model adapted to the characteristics of the MCSR (implemented in the PSCAD software) is performed. The comparison serves to grant credibility to the assumptions used for the preparation of the equivalent circuit and interpretations of the function and dynamics drawn from the analysis of this circuit. With a better and clearer understanding of the dynamics and effects of the MCSR on the network a simplified analysis of harmonic distortion is performed allowing to clarify some negative aspects of the equipment. To study the applicability and usefulness of the equipment in the Brazilian electrical system a model for electromechanical transients is proposed. The parameters that determine the dynamics and response of equipment are explored using reasonable assumptions and the characteristics of the equipment. The model is first tested and analyzed in a simplified system consisting of a generation represented as ideal source, an equivalent PI circuit representing a transmission line, a load and the MCSR performing the reactive compensation. The work follows to the choice of a Brazilian network on which the MCSR would be a viable option. A network in northern Brazil is chosen for analysis. Further studies of power flow reveals the possibility to exchange the SVS (Static Var System ) and four shunt reactors for four MCSRs. The network is then modelled in PSCAD and studies of harmonic distortion and electromechanical stability are conducted. Finally we make an economic comparison between three alternatives of reactive compensation for the chosen system including the originally adopted and the suggested solutions. The study concludes that magnetic controlled reactor are, in many cases, a cheaper alternative to the SVS and therefore should be studied in the planning and expansion of the power system.

The design of a transmission project is as varied in the factors that affect it as the people to which the project supplies electricity. This thesis focuses on the theoretical considerations in the design process that affect the emergence of reactive power in a system and how reactive compensation is achieved. It examines the place of theoretical concepts in reality by expounding on a field study on the construction of a new transmission power system connecting the North Western Province (NWP) of Zambia to the national grid. The thesis provides colour to these grey theoretical concepts in the form of conductor specifications, geometrical transmission tower relationships, load characteristics, population traits, transformer interactions and recommendations for improvements to the constructed grids using the analytic tools provided by the theoretical background. There is also provided some theoretical description of three recommendations made by this thesis to improve the power quality and general efficiency of the NWP. Along the way the thesis confirms the analytic calculations with reference to field documentation and programming tools such as MATLAB and Power World. It is the uniqueness of the system in terms of load demand and geography that allows for an analysis and comparison of the reactive power in the transmission network. These challenges and the possible solutions to them form the focus of the thesis.

In this research work detailed parallel and series equivalent circuits of a gapped iron-core shunt reactor with discretely distributed gaps are derived. The validity of the recommended equivalent circuits is verified by Finite Element Analysis and laboratory tests. Effects of fringing flux and discretely distributed gaps on inductance parameters and reactor losses are also investigated. Moving Strip Method for discretely distributed gapped shunt reactors is recommended. Two design procedures for shunt reactor with discretely distributed gaps are developed within the scope of this thesis. A simple and practical design approach is also developed which does not need any Finite Element Analysis software. This practical method is very useful for design engineers and researchers. The results of practical design approach are shown to be in good agreement with Finite Element Analysis and experimental work.

This thesis deals with the high speed transient modelling in the electrical networks. The introduction of this work discusses mathematical models of the individual devices used in the system and focuses on the line representation. It also contains a more detailed description of Bergeron and frequency dependent line model. The objective of this thesis is to design a network model using ATP-EMTP simulation program. In this model, the switching overvoltage caused by shunt reactor switching and lightning overvoltage are simulated. The thesis thoroughly describes the settings of the components used in the model of analysed network and in conclusion evaluates obtained simulation results in a relation to the insulation coordination.

Switching of shunt reactors and capacitor banks is known to cause a very high rate of rise of transient recovery voltage across the circuit breaker contacts. With improvements in circuit breaker technology, modern SF6 puffer circuits have been designed with less interrupter per pole than previous generations of SF6 circuit breakers. This has caused modern circuit breakers to operate with higher voltage stress in the dielectric recovery region after current interruption. Catastrophic failures of modern SF6 circuit breakers have been reported during shunt reactor and capacitor bank de-energisation. In those cases, evidence of cumulative re-strikes has been found to be the main cause of interrupter failure. Monitoring of voltage waveforms during switching would provide information about the magnitude and frequency of small re-ignitions and re-strikes. However, measuring waveforms at a moderately high frequency require plant outages to connect equipment. In recent years, there have been increasing interests in using RF measurements in condition monitoring of switchgear. The RF measurement technique used for measuring circuit breaker inter-pole switching time during capacitor bank closing is of particular interest. In this thesis, research has been carried out to investigate switching transients produced during circuit breaker switching capacitor banks and shunt reactors using a non-intrusive measurement technique. The proposed technique measures the high frequency and low frequency voltage waveforms during switching operations without the need of an outage. The principles of this measurement technique are discussed and field measurements were carried out at shunt rector and capacitor bank installation in two 275 kV air insulated substations. Results of the measurements are presented and discussed in this thesis. The proposed technique shows that it is relatively easy to monitor circuit breaker switching transients and useful information on switching instances can be extracted from the measured waveforms. Further research works are discussed to realise the full potential of the measuring technique.

[pt] No novo modelo para o setor elétrico brasileiro a operação do sistema é de responsabilidade do Operador Independente do Sistema enquanto que a propriedade do equipamento e os gastos com a sua manutenção são de responsabilidade do agente prestador do serviço ancilar.Desta forma, o lucro do agente prestador do serviço ancilar de potência reativa será função do custo deste serviço uma vez que a sua remuneração é previamente definida pelo agente regulador. Dentro desta ótica os riscos operacionais dos equipamentos de compensação de potência reativa, se não forem convenientemente mitigados,poderão aumentar os gastos com a manutenção e o pagamento de multa pela indisponibilidade do equipamento.Riscos operacionais são situações de sistema que estão fora da responsabilidade do agente mas que poderão reduzir o seu faturamento.Esta dissertação descreve os riscos operacionais e faz algumas sugestões para proteger o agente da redução do seu faturamento. / [en] In the new brazilian deregulated electrical network, system operation is under Independent System Operator responsibility while the ancillary service agent is the owner of the reactive power equipment and, as a consequence, is responsible for its maintenance costs. In the new model, the profit of the agent is a function of the maintenance costs because his payment is previously defined by the authorities. The operational risks of the reactive power equipments, if not conveniently mitigated, may increase the maintenance frequency and may also result in the payment of a fee due to the equipment unavailability.Operational risks are events in the electrical transmission system that are not under the responsibility of the agent but may reduce his profits. This report describes these operational risks and makes some suggestions to protect the agent against the reduction in his profits.