Comparison of surface leakage current between clean and polluted insulators under dry weather conditions

We investigate surface leakage current on porcelain insulators under dry weather conditions. Clean and polluted insulators are compared. And the relationship between their surface leakage current and weather conditions is studied. As a result, the polluted insulator gives a larger leakage current than the clean insulator. Also, it is shown that the leakage current of the clean insulator is strongly dependent on the absolute humidity.