Optimal overcurrent relay coordination in distribution system

Coordination of overcurrent relays in a meshed distribution system is a challenge task for the protection engineers. Initially it was done manually. Linear and non-linear programming optimizing techniques are very frequently used for Coordination of overcurrent relays. Presently artificial intelligence is applied for optimal co-ordination of Overcurrent (OC) relays. This paper discusses application of genetic algorithm for optimal coordination of OC relays in a loops distribution system. Combination of primary and backup relay is chosen by using graph theory, to avoid misoperation of relays.