Effect of Metal Fouling on Insulator Surface on the Decomposition Characteristics of SF6/N2 Gas Mixture

SF6/N2 gas mixture applied in gas insulated equipment can reduce the greenhouse effect of pure SF6 gas. This paper investigates the partial discharge decomposition of SF6/N2 gas mixtures under metal fouling on insulator surfaces. The results show that the decomposition products are SO2F2, SOF2, SO2, NO2, NF3 and CF4, the generation of which increases with the increase of the discharge time, but the generation of SOF2 is much higher than that of SO2F2. the generation of SO2F2, SO2, NO2 and NF3 shows a linear saturation trend with the increase of the discharge volume. the generation of CF4 increases with the increase of the PD intensity. The generation of CF4 shows a linear trend with the increase of PD intensity, which can be used as a characteristic product to characterize the fault severity of insulator metal surface fouling defects.