DEVELOPMENT OF AN IMPROVEDARTIFICIAL BEE COLONY BASEDCOORDINATION SCHEME FOR DIRECTIONAL OVERCURRENT RELAY IN DISTRIBUTION NETWORKS

A modified Directional Over-Current Relay (DOCR) operational time characteristic equation has been developed by introducing two new parameters (load current ratio and fault/load voltage ratio) into the conventional operational time characteristic equation to ensure flexibility while still retaining the necessary property of the original equation. An Improved Artificial Bee Colony (IABC) optimization algorithm has been developed by integrating a newly developed Algorithm-1 with the conventional ABC algorithm, to form a highly efficient and reliable DOCR setting optimization algorithm with a definite rate of convergence. DOCR settings optimization simulations have was carried out using IEEE 8-bus networks. The result obtained was compared with other optimization techniques reported in the literature under a similar condition. The proposed IABC based approach presented good results and a high rate of convergence in searching for the optimum solution in DOCRs setting optimization problem.