Estudo de transitórios relacionados a banco de capacitores em redes elétricas.

Abstract

The improvements in energy quality are fundamental to preserve the integrity of equipment connected in the electrical system, reduce energy losses, and avoid financial losses, consequently. The transient effects are the major cause of electrical system problems and the energization of capacitor banks is one of the activities that give rise to these effects. In this work, a theoretical revision of the concepts related to capacitor banks is presented, which will help in the analysis of the simulations and elucidate the way to reduce the problems caused by transients. The simulated system is a switching of a threephase capacitor bank with nominal power of 40 MVar, installed in a system with a 3- phase short-circuit power supply of 4 GVar, a voltage efficacy value of 138 kV and a frequency of 60 Hz, in star connection and grounded, as well for the simulation in the case of back-to-back shunt capacitor banks of nominal power 30 MVar, connected to a system with a three-phase short-circuit power of 1.8 GVar, voltage efficiency of 69 kV and frequency of 60 Hz. The studies about current and voltage transients, caused by capacitor bank maneuvers, serve as a basis for the development of electrical power protection. As a result, the risks and losses are minimized, providing quality energy and economy, mainly in the industrial sector.