A novel fault line selection method of resonant grounding system

Abstract

In order to solve the problems of fault line selection in resonant grounding system, a novel fault line selection method for distribution network was proposed in this paper. First, continuously measure three-phase voltage and zero-sequence voltage, which detects single-phase ground fault. When a ground fault occurred, the transient zero-sequence current was extracted from first line of the transmission line, the time-frequency matrix of all feeders were obtained by using S-transform, and the amplitude matrix of all feeders were constructed. Then, the correlation coefficients between the amplitude matrix of all feeders were calculated. Finally, the comprehensive correlation coefficients of all feeders were obtained, and the threshold was set to select fault line. The simulation results show that the proposed method is not affected by fault initial angle, fault resistance, fault location and network structure, which improves the accuracy of fault line selection.