Influence of dry bands on polluted insulator performance

This paper is aimed at the study of the influence of dry bands and the pollution distribution on insulator performance under impulse voltage. For that purpose, numerical simulation of electrical field and potential distribution along high voltage insulator model with different configurations of pollution layer is performed. Simulation results have showed that the increase of dry bands may improve the potential grading. The flashover voltage and critical leakage current for uniform, non uniform, continuous and discontinuous distributions of pollution deposits on insulator are also computed using a multi-arcs dynamic model. The computed results are found in a good accordance with the experimental ones.