Optimal Coordination of Overcurrent Relays Using Improved Leadership-Based Grey Wolf Optimizer

Coordination of overcurrent relays is a nonlinear and highly constrained optimization problem in a large distribution system where the operating time of all relays is to be minimized. Proper coordination of protective devices is a very crucial task for appropriate functioning of the electrical power system with distributed power generating stations. In order to solve this problem, various unconventional optimization techniques have been proposed. Random Walk Grey Wolf Optimizer (RW-GWO) is a recently developed algorithm based on improving the search ability of the leading wolves in classical GWO algorithm to overcome the issues of stagnation to local optima and premature convergence while solving nonlinear and complex optimization problems. Therefore, in the present work, RW-GWO algorithm is employed to find the optimal setting for directional overcurrent relay problem which is a highly complex problem. In the present paper, the results are also reported for classical GWO and the comparison is performed with several other optimization methods. The comparison of results demonstrates the strength of the RW-GWO in obtaining the optimal setting for the proper coordination of overcurrent relays as compared to other optimization methods.