Research on Fuse Failure and Countermeasure of Potential Transformer in Non-effect Grounding System

In the neutral point non-effective grounding system of medium voltage network, potential transformer fuse fault happened frequently, including fusing during startup and grid connection, operation, shutdown and so on, these faults will directly decrease the accuracy of measurement, metering, protection and other secondary equipment. In this paper, we used EMTP-ATP software, to analysis the typical medium voltage system wiring and parameters. The non-ground neutral system is established in single-phase earth fault occurs and disappear ferroresonance transient process simulation model, and aiming at the existing suppression measures to comparative study on the simulation results, Find out the advantages and disadvantages of different inhibition measures and give suggestions for improvement.