220kV SF6 Arc-Over Breakdown in CT Air Chamber

摘要

By chemical and electrical experiments both conventionally and non-conventionally, thorough inspections are carried out on the solid powder, gas components and chemical materials in the CT air chamber before and after flashover faults. It is testified that butyronitrile rubber plate exists in CT air chamber with frequent flashover faults; the caustic sulphur in the plate reacted with silver-gilt items and produced silver sulphide, which is the cause of flashover in CT chamber. There is a lack of industrial or national standard for inspection and supervision of chemical qualities in GIS SF6 for the CT air chamber; it results in the high impurity content and high malfunction rate of GIS CT air chamber in China.