Optimal Coordination of Overcurrent Relay Using Rao-1 Algorithm

The main objective of protection schemes in power system is to identify and remove the faulty part as quickly as possible. Coordinating the distribution systems, which are frequently protected with overcurrent (OC) relays is extremely difficult. Modern power systems use variety of distributed generators (DG) to make the operation of the system reliable, but the coordination of OC relays is a huge challenge for design protection engineers in these DG integrated distribution systems. This paper puts forward a method to develop a mechanism for coordination of over current OC relays in the distribution networks that is optimal, efficient, and accurate. The Rao-I, a metaphor-less optimization technique is used and compared with particle swarm optimization algorithm (PSO) in terms of convergence and accuracy. When DG is penetrated, a proper coordination of primary and backup relay is chosen to avoid relay malfunctions and unwanted outages. Finally, the Rao-1 Algorithm produced substantially more precise values resulting in a faster convergence time and more optimal coordination time.