Abstract:
Inspite of several formulations discussed for coordination issues of Directional Over Current Relays (DOCRs) in Micro grids,the coordination of DOCRs is yet a great task to be solved. A protection scheme is optimally designed taking both modes of microgrid operation, grid connected mode and autonomous mode simultaneously. A Multi objective approach yielding better coordination is discussed. There are two major objectives as follows; former is the synchronization period between primary and secondary relays, latter is the relay operation time. The problem is solved using Modified Firefly Algorithm (MFA)and the simulation results show that the DOCRs operates with better coordination both in autonomous and grid connected mode.
