Research on loop closing operation in 10 kV arc suppression coil grounding distribution network

Due to the amplitude and phase difference of the busbar voltage on both sides of the loop point, excessive loop current occurs in the loop closing operation, causing overcurrent protection or quick-break protection misoperation. This paper takes the loop closing operation of two 10 kV arc-suppression coil grounding substation in Hangzhou as an example, use ATP-EMTP software to build the simulation model. The simulation accurately simulates system operation state at the closing time and observes the change of the closing current to determine whether the loop closing operation is carried out. The factors affecting the size of the loop current are analyzed, and several methods for reducing the loop current are explored. The conclusions have great significances for the practical loop closing operation of the power system.