Surface Flashover Characteristics of Spacer in C4F7N-CO2 Mixtures Under AC Voltage

Sulfur hexafluoride is a dominated insulating gas in electric system due to its remarkable dielectric insulating properties and arc-quenching capability. However, as a greenhouse gas, the concentration of SF6 in atmosphere increase 50% during the last decade1, numerous studies have been taken to find alternatives of SF6. Among the alternatives, C4F7N is a promising insulating gas developed by 3M. It has low GWP and high dielectric strength compared to SF 6
²
.