Optimal Coordination Of Distance And Directional Overcurrent Relays Using GA

Proper coordination between distance relays and overcurrent in the power system is one of the most important issues for security and stability of system. This paper presents a new method for optimal distance and directional overcurrent relays coordination by considering high set element and different characteristics for all overcurrent relays by using genetic optimization algorithm. Using high set element with the change in coordination constraints provides possibility of adjusting the second zone time of distance relays with constant and classical value. The proposed method is applied to 8-bus and the IEEE 30-bus test systems and simulation results, show usefulness of this method in reducing operation time of protection system.