Single ground fault location algorithm in DC microgrid based on wavelet transform

Abstract

As the proliferation of distributed generation and power electronic equipment in power systems, direct current (DC) microgrid has emerged and attracted more research attention. Protection of DC microgrid is a significant challenge and to build a well-functioning protection system, locating faults accurately is important. This is especially the case with the location of ground faults in DC microgrid because of the high likelihood of capacitors connected to ground associated with the connected distributed resources. The focus of this paper is to apply Wavelet Transform to decompose the common mode currents which are collected at different sensor points in a community DC microgrid and methodologies for the capture and characterization of single ground faults at different locations within the microgrid. Based upon these characterizations, a single ground fault location algorithm in DC microgrid is proposed. MATLAB/Simulink and PLECS are used to assist in the process. A community DC microgrid model is built based upon the sharing of energy resources among interconnected homes and single ground faults at different locations are applied.