Coordenação da proteção de sobrecorrente com curvas inversas em redes com geração distribuída

Abstract

The world environmental scenario has been pessimistic about the future and its sustainability. This is due to the fact that fossil fuels generate great damage to the environment. Recently, there has been a change in the mentality of society and a greater sensitivity to the problem that made politicians adopt more forceful measures of combat those causing environmental problems. One form of solution is presented by through Distributed Generation (DG), where the customer is led to produce their own energy from renewable sources and inject the surplus into the network. However, utilities are faced with a new reality in which not only substations are active elements in the network, but also the GDs and this implies greater care with protection, since in an eventual short circuit, GDs will also inject at the point of fault, requiring a better precision in the coordination of protective devices. In this work were elaborated coordination between electrical system protection devices using Inverse Curves based on short-circuit current levels. The results of the analysis implemented in the Etap software allowed obtaining consistent results on the behavior of the Inverse Curves in scenarios that compromise network security like Overreach, Infeed and False Tripping. The results allowed us to reach the conclusion that the Inverse Curves are more efficient in coordinating protection devices, if compared to classical methods of coordination exclusively by Time or exclusively by Current, in addition, are more advantageous, as they are dynamic, allow for different operating times of the devices of protection according to the variation of the levels of short-circuit currents.