Effect of Larger Water-cut Sheds on Contamination Withstand Voltage Performance of Hollow Core Insulators under Heavy Rain Condition

摘要

In China, it is becoming problem that the flashover is frequently occurred on vertical poecelain bushings covered with contamination under heavy rain condition. In order to improve contamination withstand voltage performance of hollow core insulators under heavy rain condition, larger water-cut sheds should be proposed. As a first step, to find out the suitable water-cut sheds arrangement, total seven specimens of hollow core insulators with/without water-cut sheds having different interval and projection with 2.5m height. As a second step, to confirm the effect of suitable water-cut arrangement, the heavy rain test carried out for specimen with 5.0m height without water-cut sheds, with regular water-cut sheds and larger water-cut sheds at both China Electric Power Research Insutitute (CEPRI) and NGK Insulators, Ltd. (NGK). As the results, the withstand voltage was improved by larger water-cut sheds and the suitable design of water-cut sheds was verified.