Study on resistive coupling interference of Operation of Disconnecting Switch in GIS substation

Operation of Disconnecting Switch (DS) and Circuit Breaker (CB) can produce very fast transient overvoltage (VFTO) in GIS. During the transmission process of VFTO in GIS, as the backflow route of VFTO, corresponding high frequency interference can be induced on the shell of GIS. High-frequency interference´s entering into grounding network can cause transient ground potential rise (TGPR), resulting in resistance interference. The paper focuses on the transmission characteristics of high frequency interference caused by VFTO, and analyzes factors affecting interference voltage transmission through changing grounding network parameters. For the typical grounding network structure and actual grounding network model in a substation, transmission factors affecting interference voltage in the grounding network are analyzed through changing grounding network parameters to discuss the interference caused by DS operation on GIS substation via resistance coupling mode.