AC flashover characteristics of EHV line insulators for high altitude contamination regions

The relationship between the pollution flashover voltage and atmospheric pressure is presented. It is based on experimental results for three types of standard and antipollution line insulators with large leakage paths, carried out in a climate chamber. The principle of the characteristic exponent, n, which represents the decrease of pollution flashover voltage with the decline of atmospheric pressure, is proposed. The pollution flashover characteristics of these insulators are analyzed.<>