Metodologia para análise de transitórios eletromagnéticos durante paralelismo em redes de distribuição com presença de geração distribuída

Abstract

The parallelism of radial feeders of primary distributions networks is a technique that can be used to change the topology of the network under normal operating conditions, scheduled maintenance, or even in contingency cases. In this paper, contributions related to the study of parallelism in smart grids endowed with the capacity of self-healing are presented. Self-healing comprises automatic energy recovery systems capable of detecting and identifying different types of faults in the system, diagnosing the cause of the interruptions in supply, and quickly compensating the problem with the support of neighboring feeders. To minimize the time of interruptions, maximize the number of clients restored and reduce the defective area of the network, parallelism, which consists of temporarily connecting the system feeders in ring arrangement to transfer load between them, is a tool that can speed up the network recovery process. In this sense, the proposal of this work is the development of a methodology for the analysis of the technical feasibility of parallelisms in distribution networks to restore the electric energy to the largest possible number of consumers, with cascade transfers of loads between their feeders. The case under study covers a particularity of distribution systems, which happens when certain feeder cannot supply new loads without having part of its load relieved to another feeder. During the change of network topology, by opening and closing remote-controlled switching devices, such as automatic disconnecting switches or reclosers, undesirable electromagnetic transients in the voltage and/or current may occur, causing damage along the network. To make this analysis even more realistic, the proposed methodology in this work is tested in a case study in a distribution network with a Volt-Var control device and a dynamic model of distributed generation. The technical and operational feasibility of the maneuvers is verified through computational simulations in the ATPDraw program. The results show that this application is agile and efficient and meets the objectives of the self-reestablishment of distribution networks in a situation of contingency.