Effect of the surface roughness of epoxy resin on its creeping flashover characteristics in C4F7N-CO2 gas mixtures

Abstract

Epoxy resin samples were processed by one direction and multi-directions polishing methods in this research. The contact angles of the samples, the AC/DC flashover voltage in C4F7N/CO2 gas mixtures and the charge dissipation rate of the polished samples were measured. The results show that the contact angle of the polished epoxy resin sample increases. In the gas mixtures, the surface roughness modification of the epoxy resin under different voltage types is proposed. According to the charge dissipation rate, the development mechanism of creeping flashovers under different voltage is revealed. Different dissipative properties ultimately enhance the creeping discharge voltage of the samples by suppressing electron secondary electron emission. This paper offers a basis for insulation design in the C4F7N/CO2 gas mixture.