Mastering electrical faults in high voltage stations insulated using SF6

Faults occurring in electricity substations were analyzed. While most faults appear during the first few months of operation and can be attributed to running-in problems, or are due to human error, the possibility of arc discharges remains. These discharges cause a sudden increase of heat and pressure in installations and can provoke chemical reactions with insulating materials. Guidelines for selecting materials and designing systems to limit arc induced damage are presented.