A New Phase Selection Method for Single-Phase Grounding Faults in Distribution Networks with Full Compensation Arc Suppression Technology

Faulty phase selection is one of the core technologies of full compensation arc suppression system for single-phase grounding faults in distribution networks. At present, faulty phase selection is mainly used for single-phase automatic reclosing and distance protection algorithms in direct-earthing systems. These methods have applicability problems in single-phase-to earth faults in non-effectively grounded distribution networks because of different neutral voltage. when the theoretical current is injected, whose value is determined by the full compensation arc supperssion method, voltage of the healthy phase, which is the miss-selected phase, will approach to a non-zero certain value as transition resistance increases; if the phase is selected correctly, when the corresponding current is injected, the selected phase voltage will be close to 0. This feature is used to distinguish the faulty phase, and thus promoting the full compensation arc suppression technology used in distribution networks.