Fault Analysis of Successive Faults on Multiple Feeders in Resonant Grounding Distribution Network

Successive faults on multiple feeders occur frequently in resonant grounding distribution networks, which is doing serious harm to the reliability of power supply. In this paper, the steady-state overvoltage caused by single-phase-to-ground fault is analyzed, and the distribution characteristic of transient overvoltage caused by intermittent earth fault is studied, indicating that overvoltage level on a healthy line may be higher than that on the faulty line. For this reason, a phase-to-phase fault may occur on a healthy line before occurring on the faulty line. For further study on the developing process of successive faults, a simulation case is built in PSCAD/EMTDC based on an actual accident. Combining with the fault information, the causes of successive faults on multi-feeders are revealed.