Novel Protection Scheme for Low Voltage DC Micro-Grid System

This paper presents a method for detection and isolation of fault in DC-bus microgrid system. The protection of DC system has been challenging when compared to the traditional AC system. The DC-bus microgrid system consists of a source, storage and load. The protection scheme isolates only faulty section from the DC grid. Healthy sections are operated without any disturbance and supply continuity is maintained in a loop type system. The current sensor placed at both ends of distribution line continuously monitors the current. Because of fault, current difference occurs in two ends of line. Controller detects this current difference and opens the power switches. To meet the requirement of fast interrupting time and high shortcircuit current withstanding capability, IGBTs are used as power switches. The protection scheme concept has been verified by MATLAB/SIMULINK