Investigation on leakage current, erosion, and hydrophobic performance of high-voltage insulator coatings of different thicknesses

Abstract

Room-temperature vulcanizing (RTV) silicone rubber is used as a high-voltage insulator coating to enhancethe pollution performance of conventional insulators, and the electrical performance of RTV coating depends on theseveral parameters. The present study shows the effects of the thickness on the leakage current, erosion, and hydrophobicperformance of high-voltage insulator coating. Several different thicknesses of RTV silicone rubber were taken intoconsideration on porcelain substrates. Erosion and leakage current performances of the samples were evaluated by usinginclined-plane tests (IPTs) based on the IEC 60587 standard. Eroded masses and fundamental and harmonic componentsof the leakage currents were investigated with respect to coating thicknesses. On the other hand, hydrophobic featuresof the samples were evaluated by using dynamic drop tests (DDTs) with regard to CIGRE TB442 documentation. Timeto loss of hydrophobicity and the level of the leakage currents were investigated in DDTs considering the thicknesses.