Flashover Characteristics of the Interface of SF6-Epoxy Resin Impregnated Paper with Particles Contamination

Valve-side epoxy resin impregnated paper bushings are an important part of the UHV DC transmission system. During the creation, gathering and activity of power equipment, for example, converter valve-side bushings, very fine metal and non-metal particles are left in the equipment, which seriously threaten the ordinary activity of the equipment. In this paper, according to the actual working condition of epoxy resin impregnated paper(ERIP) bushing on converter valve side, the surface flashover experiment of ERIP with particles attached to the surface of vertical electric field structure is carried out under the environment of 1:7 AC/DC superimposed voltage. The results show that the metal particles affect the flashover qualities greatly. The flashover voltage decreases the most when it is close to the high voltage electrode, and the larger the particle size, the more obvious the flashover voltage decreases. The impact of non-metallic particles on the flashover characteristics is small, and the influence is relatively large when close to the electrode. Finally, the experimental results are confirmed by the electric field simulation, and this paper provides some theoretical value for the fault diagnosis of resin impregnated paper bushing.