DEVELOPMENT OF INSULATION STRUCTURE AND ENHANCEMENT OF INSULATION RELIABILITY OF 500 KV DC GIS

The paper describes the development of insulation structure and enhanc ement of insulation reliability of 500 kV dc GIS. Considering problems of metallic particles and charge accumulation on spacers, the develop ed insulation structure of GIS consisted of three regions, i.e. the sp acer, particle scavenging and non-levitating regions. Particles could be efficiently scavenged, and the developed GIS withstood all insulati on specifications with sufficient margins under the clean and particle -contaminated condition. Now, a long-term site test for one year of th e 500 kV de GIS has been continued since October in 1995.