Optimal Combined Overcurrent and Distance Relays Coordination Incorporating Intelligent Overcurrent Relays Characteristic Selection

In this paper, a new objective function (OF) within the genetic algorithm (GA) approach is presented to solve the optimization problem of coordination of overcurrent and distance relays. The existing objective function of overcurrent (O/C) relays coordination is improved and extended to include the coordination of O/C and distance relays. Various O/C relays characteristics are considered within the approach to select the best of them by GA to fulfill optimal coordination. The proposed method is applied to two different power system networks. Simulation results demonstrate that the method can obtain feasible and effective solutions for optimal coordination in the practical power system networks.