Study on method of single-phase-to-earth fault section location in neutral point resonant grounded system

摘要

Due to the large amount of branches and high grounding resistance of the distribution network, the earth fault location has not been solved effectively. A live location method is proposed for the single-phase-to-earth fault section in the neutral point resonant grounded system. By this method, the compensation current of arc-suppression coil is adjusted after the metallic earth fault occurs. And the fault section can be confirmed by the variation of zero-sequence current measured by FTU equipped in the lines, for the zero-sequence current in the non-fault path is proportional to the zero-sequence voltage. When the single-phase-to-earth fault via resistance occurs, zero-sequence voltage changes after the arc-suppression coil is adjusted. The method is also effective as long as the zero-sequence current is converted by zero-sequence voltage. The site experiments have been carried out to prove that the method is feasible.