Partial discharge and decomposition characteristics of environmental insulating gas C5F10O under different background gases

Abstract

SF6 is widely developed and applied in gas insulated electrical equipment due to its excellent arc extinguishing performance and insulation performance. However, SF6 is very destructive to the ozone layer and has a strong cumulative effect on the greenhouse effect of global warming. Therefore, the inevitable trend of the development of power grid equipment in the future is to reduce or even prohibit the use of SF6 gas in the power system, power industry and electrical equipment, or to find insulation media that can replace SF6. As a result, the research on environment-friendly insulating gas has become popular. In this paper, power frequency partial discharge platform and GC–MS​ detection platform are used to systematically study the partial discharge and decomposition characteristics of C5F10O under N2 and CO2 background gases. The partial discharge extinction voltage (PDIV) and partial discharge statistical characteristics of C5F10O under two different background gases, as well as the variety and concentration change of mixed gas decomposition products are theoretically analyzed and compared with SF6. It is found that, similar to SF6, the PDIV of C5F10O under two kinds of background gases increases linearly with the increase of air pressure. The PDIV under N2 background is smaller than that under CO2 background under the same conditions, and its insulation performance is slightly better than that under CO2 background. The partial discharge decomposition of C5F10O mixed gas mainly produces fluorocarbons such as CF4, C2F4, C2F6, C3F8, C3F6, and a small amount of CO, COF2, C3HF7, and CHF3. The increase of air pressure inhibits the partial discharge decomposition of mixed gas.