Optimized DOCR Setting by Considering Generator Scheme and Different Configuration on Ring System

This paper aims to obtain optimal directional overcurrent relay (DOCRs) settings, which is a common problem in power system protection. This study was conducted in the industrial plant that used ring main distribution topology. Unlike previous research, this paper considers the impact of generator operation schemes. In addition, this paper also deals with the condition where one of the feeders is open on the ring main distribution system and change its topology to a radial network. Both of the conditions above have impact on DOCRs setting. The differential evolution (DE) algorithm is used to obtain the optimal time dial setting (TDS) for the relays connected in the network. Two variant mutation strategies of the DE algorithm have been implemented and compared respectively to fill the gap of previous study. The difference of operating time between DE/best/1 and PSO on all cases is above 25% while DE/best/1 and DE/rand-to-best/l is above 8.7%. This study concludes that the best mutation strategies method for solving DOCRs setting is DE/best/1. In addition, DE/best/1 has been compared with particle swarm optimization (PSO), the results concludes the DE/best/1 more optimized than PSO.