Avaliação dos Impactos da Impedância de Falta e da Geração Distribuída em Estudos de Afundamentos de Tensão

Detalhes bibliográficos
Ano de defesa: 2009
Autor(a) principal: RAMOS, Alessandro Candido Lopes lattes
Orientador(a): ALVARENGA, Bernardo Pinheiro de lattes
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Goiás
Programa de Pós-Graduação: Mestrado em Engenharia Elétrica e de Computação
Departamento: Engenharia
País: BR
Palavras-chave em Português:
Palavras-chave em Inglês:
Área do conhecimento CNPq:
Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tde/988
Resumo: This work presents an impact analysis of the fault impedance and distributed ge- neration on the amplitude and annual average quantity of voltage sags in sensitive end-users. Phase-to-ground solid and non-solid faults were simulated in 62 transmission lines at 230, 138, 69 and 13.8 kV, which made part of the electrical system of the municipality of Goiânia, the capital city of the Goiás State, Brazil. For each fault position, a resistive fault impedance was considered. This impedance was considered equal to 0, 2, 5, 10, or 15  or even random. In this case, each one of the mentioned impedance values has a specific probability to occur. The voltage-behind-reactance synchronous machine model was used to model the distributed generation units. The analysis here described is based on simulation results obtained through the Fault Position Method in combination with the Monte Carlo Method. The faults were si-mulated through a frequency-domain fault simulation software called ANAFAS. In order to overcome some limitations and increase the flexibility of the simulation tool, a computational program, called ANAFAS-GUI, was developed in Java language. This program allows the automatic simulation of several cases, with different fault characteristics, by running ANAFAS in background mode. The Monte Carlo Method was implemented in MATLAB. Thus, an efficient computational tool has resulted from the combination of the developed computational tools for the purposes of this work. The main simulation results are the tenden-cy and probability density curves of the voltage sags and their classes. From the results it can be concluded that, if the fault impedance is considered as being a random variable, then the predict voltage sags quantity and severity at the sensitive end-user bus are more accurate when compared to the cases in which this impedance is not considered as such. It can also be concluded that, the connection of a distributed generation unit next to the sensitive end-user bus may result in a decreasing of the voltage sags quantity and severity at this bus, depending on the rated power of the unit