Estudio de coordinación de protecciones en el Sistema de Subtransmisión de la Empresa Eléctrica Quito considerando la conexión de la Línea Vicentina-Santa Rosa 138 kV

Abstract

This work presents an overcurrent and distance protective relay coordination study before the energization of the Vicentina-Santa Rosa 138 kV line located in the south-eastern zone of the subtransmission system of the Empresa Eléctrica Quito (EEQ). The EEQ subtransmission system and the topological change caused by the interconnection of the Vicentina-Santa Rosa 138 kV line is modeled in DIgSILENT PowerFactory under four operating scenarios with information provided by EEQ. On the modeled system, the area of influence of the topological change was delimited adequately, and a short-circuit study was performed to determine the new short-circuit powers of the substations that were affected. In addition, the results obtained from the short-circuit study were used for sizing current and voltage transformation relations located within that area, as well as for the verification of the operational capacity of breaking and switching equipment for the new current requirements. In the same system, a protection coordination study was performed using adjustment criteria for the distance and overcurrent relays installed within the influence zone, whose validation was studied in the four operating scenarios modeled through the simulation of different short-circuit case studies. These cases were different from those considered for determining the settings, so that a finer adjustment was obtained for each protective relay.