Protection of Over Current Relay in Microgrid Protection Using ETAP

In modern power systems, the electricity demand increased due to technological improvements and increased population. The solution to meet the demand is the penetration of RES (Renewable energy sources). In power system engineering, the protection scheme plays an important role as well as a challenging task due to the high integration of RES. In this paper, the relay coordination analysis has been developed to achieve sequence operation of the relay concerning fault current and minimum usage of relay and circuit breaker. The relay sequence operation with fault current can be carried out by over current and instantaneous protection scheme. For this analysis, an IEEE 9 Bus Microgrid system has been designed using ETAP industrial software. To achieve relay coordination with minimum relay tripping, the relay setting parameters need to be selected. The relay setting can be done with the help of the Load flow and short circuit analysis. In this paper load flow analysis and short circuit analysis are studied for different types of scenarios, and it defines how load flow and short circuit analysis results differ when integrating RES into the main system. The different scenarios are without the inclusion of a PV source and with the inclusion of a PV source.