Optimail Strategy for Over Current Relay Coordination Using Genetic Algorithm

In conventional methods coordination of Over Current relays (OCR) is obtained through careful time grading. Due to the expansion of electric systems, the need for an efficient coordinated protective system is crucial. The optimal time for protection given the coordination problem turned to be little complex to be calculated. To solve the problem of the coordination of OC relays, Genetic Algorithm (GA) technique is applied. The purpose of the OC relay coordination is to find an optimum relay setting to minimize the time dial setting (TDS) and calculate the pickup current (Ip). Setting of the relay is the core of the coordination study to satisfy the primary and secondary operation. This paper presents an application of GA technique for optimal coordination of OC relays to a 6-bus ring system.