Performance Analysis of the Overcurrent Protection for the Renewable Distributed Generation Dominated Microgrids

This paper aims to present a study of the conventional protection scheme i.e. overcurrent (OC) protection's malfunctioning in the microgrids dominated by inverter interfaced distributed generator (IIDG) under a range of scenarios by injecting faults at different locations of the network. Due to low cost and inherent back-up protection, overcurrent scheme is considered to be the main protection for the distribution networks and microgrids. However, the integration of IIDG in large number might introduce several protection challenges for microgrids. Existing literature discusses the protection issues that might arise in microgrids due to addition of distributed generation, but those challenges are not practically studied. Hence, in this paper, several fault cases are simulated by changing fault positions and using different combinations of IIDGs in the network so that protection challenges can be fully explored and performance of the overcurrent relays in the IIDG dominated microgrids can be analysed under those simulated cases.