Micro-redes elétricas: estado da arte e contribuição para o dimensionamento, aplicação e comercialização da energia produzida.

Abstract

After the occurrence of some major blackouts like the one that affected the Northern and Northeastern part of the United States in 2003, the one that affected the Southeast, Midwest and Northeastern part of Brazil including Paraguay, in 2009; and the blackout that affected the whole Italy in 2003, to mention a few a few of them, there was a rush for seeking some alternatives to deal with such events or at least find out feasible solutions that can contribute to diminish their impact. The lack of electric power, for whatever reason it was, unveiled one common fact, our modern society is so dependent on electricity that during the blackouts areas like the electrical transport system, financing activity, academic institutions, industries, health centers with no emergency or standby generation, public and residential lighting and even some communication systems failed to operate. The establishment of microgrid systems proved to be an alternative that could be used for this purpose; thus, not only critical loads, but also some of the activities mentioned earlier on could continue their operation during such emergency periods. In addition, the concept of micro-grid systems has recently gained particular attention due to the increasing penetration of distributed generation and also due to the incentives provided by the governments to promote the generation of electricity from renewable sources such as wind power, solar, biomass, small hydroelectric schemes, etc. At present, countless settlements located in remote areas worldwide use microgrid systems to generate and distribute electricity. In this work, the results related to the microgrid technology, specifically its performance towards system conditions such as the islanding mode and grid connected mode of operation will be presented. Particularly, the transition to the islanded mode of operation demanded a more dedicated study during the simulations performed. As for the energy trading between the microgrid and the utility, which can occur when the microgrid generators are lightly loaded, it will be presented a critical analysis about the possible tariff methods to be applied. Such tariffs are so far only applied in the form of government subsidies to promote the use of renewable energy sources. Additionally, an analysis of a microgrid economic feasibility to show how competitive or complimentary this technology is with the utility will be presented herein.

Fluxo De Carga Em Sistemas Elétricos De Potência – Um Estudo De Caso Usando a Linguagem Ampl

“…Segundo Huayllas (2015), uma microrrede pode ser composta por uma ou mais fontes associadas a uma carga, podendo operar de forma independente ou ligada à rede de distribuição principal. Para o consumidor, uma microrrede tem o objetivo de reforçar a confiabilidade, aumentar a eficiência e melhorar a qualidade da tensão.…”

“…Fonte: S&C(2018). Huayllas (2015) define o modo de operação conectado à rede como uma forma de oferecer suportes reativos a rede, controlando a tensão local e injetando potência ativa na mesma. O modo de ilha é dividido em dois modelos, o planejado, o qual resulta na geração de pequenos transitórios de tensão e, apesar de alguns possíveis problemas de desequilíbrio entre carga e geração, é um modo atrativo para os consumidores no ponto de vista econômico, e o forçado, que ocorre devido à presença de falhas na rede de distribuição pela presença de perturbações.…”