Development of 500KV Gas Insulated Switchgear and its Application

The application of Gas Insulated Switchgear (GIS) up to 275kV substations has been proven and the authors have been working jointly on the research and development, with a view of supplying GIS for the 500kV trunk systems in the near future. To demonstrate the reliability and intearity of GIS. a prototype installation was provided and subjected to excess voltage and current during endurance and service tests. The satisfactory results obtained have led to the Kansai Electric Power Co. (KEP CO) Japan placing orders for a 500 kV substation to be commissioned in March 1973. The paper covers some specific engineering problems encountered on 500kV GIS, the results of tests and the investigations of its application.