Dynamic characteristics of high-voltage insulation with metal oxide elements

The dynamic behavior of an insulation assembly and a metal oxide element is modeled. The multiple arc model, including the characteristics of zinc oxide varistors, was used to evaluate the critical flashover voltage of a dynamic insulator unit. The leakage current through the varistor has the effect of drying the insulator surface, thus increasing the withstand voltage. Nonuniform contamination distribution results in reduction of the critical arc length but has no significant effect on the critical flashover voltage