Simulation of Radial Electric Field and Voltage Distribution of 500kV MOA Under Different Conditions of Pollution

500kV zinc oxide arrester is usually arranged outdoors. The surface of its porcelain sleeve will be contaminated by local environmental pollution and weather factors such as frost, rain and snow. The surface flashover problem caused by pollution is similar to that caused by insulator surface pollution. The difference is that there are three resistor columns connected in series inside the arrester. The influence of surface contamination on the voltage distribution of the internal resistor and the radial electric field between the resistor and the porcelain sleeve needs to be studied. In this paper, a two-dimensional axisymmetric simulation model of 500kV zinc oxide arrester when its surface is polluted was established. The electric field distribution of the porcelain sleeve is simulated when it is clean, uniform and partially dry. The voltage distribution of the resistor under different pollution conditions and the radial electric field between the resistor and the ceramic sleeve are compared and analyzed.