Protection coordination for a distribution system in the presence of distributed generation

This paper proposes an effective strategy to overcome the impacts on coordination among protection devices due to distributed generator (DG) integration. Increased fault current magnitude and changes in power flow directions are the major impacts imposed by DGs on a typical distribution system. The recloser-fuse coordination is much influenced upon the integration of DGs. The proposed approach presents the rehabilitation of recloser-fuse coordination for post-DG integration effects using the directional properties of a recloser. The simulation results show that coordination among protection devices can be regained using fast operation of the recloser to design a fuse saving scheme in the scenario of temporary fault occurrence. The designed scheme also works satisfactorily for the isolation of a permanently faulted section of the feeder. This technique is verified by simulation results performed on a real 11-kV radial distribution feeder for different fault locations and DG sizes.