Improvements to the performance of silicone rubber housed composite bushings by means of a resistive coating

Abstract

Local discharges in the vicinity of the mounting flange of composite bushings due to the electric field enhancement and dry band arcing on the surface of composite bushings can cause insulating material degradation leading to failure of the bushing. A proposed solution to this problem by employing a resistive silicone rubber coating on composite HV bushings was investigated. Good agreement was obtained between computer software simulation by FEMLAB/spl reg/ and measurement results of potential and field distributions. Wetting and salt-fog chamber tests verified that the resistive silicone rubber coated composite bushings have superior contamination performance.