ABSTRACT

In a power system, one of the most critical aspects is power protection. Power protection involves using protective devices to insure that in the case of a short circuit or any electrical fault, system components are not damaged and as little of the system is taken down as possible. In order to provide adequate protection for the circuit, these fault conditions must be simulated and analyzed.This paper illustrates a novel protection scheme using digital over current relay (directional and non-directional) for microgrids and its performance verified by simulation in matlab/simulink. The paper also shows various steps involved in converting relays into a data converter by digitization process. The logic based algorithm and developed relay model have been tested under various system dynamics and fault conditions. Small microgrid network is constructed and performance of digital over current relay is analyzed. A microgrid network is proposed with placement of relays and protection for various parts of network. The coordination of relays is designed using ETAP’s STAR module.