A Study on Correlation Between Electrical Performance and Physical Dimensions of Suspension Insulator

Suspension insulators can be damaged for various reasons during their service life. The choice of suspension insulator with good electrical performance is important. It is expected that physical dimensions and shapes play an important role in electrical characteristics. In order to investigate the correlation between physical dimensions and electrical performance, suspension insulators from several manufacturers are tested and the obtained results are analyzed. The tests consist of dimensional measurements, dry and wet flashovers, critical impulse flashovers and leakage current measurement. Then the correlation coefficients are determined. The results show that a suspension insulator with smaller maximum cap diameter has a tendency to have higher leakage current and higher dry flashover voltage. Additionally, the bigger the outer insulator diameter, the lower the leakage current and dry flashover voltage. Meanwhile, the increase in leakage current is due to a shorter leakage distance, or arcing distance. Least of all, the positive CFO rises as the shed angle declines.