OVERCURRENT RELAY COORDINATION IN DISTRIBUTED GENERATION WITH FAULT CURRENT LIMITER

The distribution network has many advantages when it is connected to distributed generation (DG). Some problems in coordination of protection devices will occur in the presence of DG, due to change in short circuit level at different points. Fault current limiter (FCL) is applying limit to the fault current levels and the effect of DGs on coordination of overcurrent (O/C) relay during the faults. In distribution network the use of FCL & DG causes some transient current during fault condition. In such network steady state coordination method do not result inaccurately. In this method we use fault current limiter for reducing the transient fault current in the network. The method gives feasible and effective solutions for optimal coordination in the practical power system networks in comparison to the previous steady state methods when simulations are carried out on a sample network and the results are demonstrated