Contamination withstand voltage characteristics of hydrophobic polymer insulators under simulated rain conditions

Contamination withstand voltage performance of hydrophobic polymer insulators is influenced largely by wetting conditions. Heavier wetting, such as heavy fog and rain could give lower contamination withstand voltages compared with the light fog conditions specified for conventional ceramic insulators. Using the newly installed power source stiff enough for contamination tests, systematic investigation has been conducted on vertically and horizontally installed specimens under different precipitation and water droplet conditions. Simulated rain test is proposed to be included for evaluation of insulation performance of contaminated hydrophobic polymer insulators.