Relay coordination in DG integrated system

Abstract

Distributed generators (DGs) are integrated into the distribution network inorder to reduce power loss, voltage profile improvement, reduction of operation cost and to reduce environmental impacts by conventional power stations. When DGs are integrated into the network and also when network topology is changed, the existing protection system fails to operate properly. The relay miscoordination can be overcome by updating the settings of protection system. In this work, load flow analysis and short circuit analysis for the power system network are done and load current, maximum and minimum possible fault currents are computed. Effect of DG in protection system of a distribution network is observed. Variation in fault current with respect to system factors is analysed. An adaptive overcurrent relay is modelled using Arduino UNO. Particle Swarm Optimisation is done to find out the optimum settings of relays. Relay coordination is done in a four bus system, IEEE 14 bus system and IEEE 13 bus system using the optimal values.