New Method of Active Arc Suppression and Phase Selection Based on Zero Sequence Current Regulation in Distribution Network

Abstract

In order to solve the problem of arc suppression and phase selection of single-phase grounding fault in neutral point non-effectively grounded distribution network, an active arc suppression and phase selection method based on neutral point zero sequence current regulation is proposed in this paper. After single-phase ground fault occurs, a specific zero sequence current is injected into the neutral point by a controllable current source to eliminate the influence of three-phase to ground parameter asymmetry on phase selection, and then the fault phase is selected according to the phase comparison of zero sequence voltage displacement. Furthermore, the zero sequence current is regulated by a controllable current source connected to the neutral point to compensate the full current of the grounding fault and suppress the fault phase voltage to zero, to realize the safe arc suppression of the grounding fault. In PSCAD / EMTDC simulation environment, a single-phase to ground fault model of distribution network is built, and simulation results show that reliable arc suppression and correct phase selection can be achieved under different transition resistance, which verifies the feasibility of the proposed method in this paper.