Plasma Enhanced Chemical Vapor Deposition Treatment Improves the Surface Flashover Performance of Epoxy Resin

Epoxy resin is a common insulating material in gas insulated transmission lines (GIL) and gas insulated metal switches (GIS), due to its excellent electrical and mechanical properties. Long-term operation in DC high-voltage and high-power environment will cause surface flashover or even failure, which directly reduces the insulation performance of epoxy resin and affects the safe and stable operation of the power system. In this paper, plasma enhanced chemical vapor deposition (PECVD) was used to treat epoxy resin to improve its flashover performance. A pulsed discharge plasma treatment platform was built, and tetraethyl orthosilicate was selected as the reaction precursor to react under the action of plasma, and SiOx films were deposited on the surface of epoxy resin samples. Experimental studies under different treatment time and pulse parameters were carried out, and the materials before and after treatment were characterized. The experimental results show that the physical morphology, chemical properties and electrical properties of epoxy resin have changed after the deposition of SiOx. The mechanism of surface flashover performance improvement is discussed by combining various measurement methods, which provide the experimental basis for solving the insulation problems faced by HVDC equipment.