Coordination of Over Current Relays in Distributed Generation

The modern power system increases the power by adding Distributed Generation (DG). When distributed energy sources are added to the network, they effect the conventional fault levels and fault current paths and have been proved that the accurate operation of the overcurrent protection is not possible. This paper describes time overcurrent relay protection for radial distribution system (RDS) with DG. These time overcurrent relays is implemented by using IEC-60255 standard. The proposed protection outline is verified on a typical IEEE 13-bus radial distribution system with distributed energy source. The model of the system is replicated by using MATLAB/Simulink.