Uthitsunthorn, D., Pao-la-or, P., & Kulworawanichpong, T.
This paper presents optimal coordination of overcurrent relays by using artificial bees colony algorithm. The objective function of the relay coordination problem is to minimize the operation time of associated relays in the systems. The control variables used in this paper are the pickup current and time dial setting of relays. The proposed method was tested with four systems study consists 5-bus, 6-bus, 9-bus and 14-bus. Quasi-Newton (BFGS), particle swarm optimization (PSO) and artificial bees colony (ABC) are employed to evaluate the search performance. For test, there are study test power system was used. The simulation results showed that the artificial bees colony algorithm is capable to minimize the operation time of relays in the entire system. As a result, all search algorithms can solve optimal coordination relay which the artificial bees colony (ABC) gives the best solutions for coordination relay setting.