Technology research of fault automatic isolation in distributed single-phase-to-ground based on voltage-time type recloser

A new method is presented by combining fault line detection and automatic recloser to achieve single-phase grounding fault insulation and resume non-fault section automatically. This paper discusses conjunctive mode between fault line detection and automatic recloser, i.e. through recloser determining fault section firstly, and isolating fault section secondly. The method can select fault line and isolate fault section quickly. The method is beneficial to clear faults quickly, improve the security and reliability in the run, and also create condition of quick and exact fault location. Practical local operation verifies the correctness and feasibility of this method fully.