Fault Analysis in a Grid-tied Microgrid System

Faults occurrence in electric power systems are inevitable. The introduction of grid-tied micro-grid could further increase the occurrence of these faults. This is because micro-grid consists of many associated components which could develop faults thereby increasing the overall fault occurrence on the power system. Therefore, there is a need to investigate the behaviour of a micro-grid when any of its components is under fault condition. This is imperative in order to design adequate protection schemes. In this work, fault conditions are simulated and analysed in a grid -connected micro-grid using Real- Time-Digital Simulator (RTDS). The simulator allows a true reflection of the behaviour of the micro-grid under faulty conditions. Three fault scenarios are considered for the purpose of the investigation. The results show that the most severe fault to the load infrastructure would be the occurrence on the grid side of the system.