STUDY ON PERFORMANCE OF SEMICONDUCTING GLAZED INSULATORS UNDER SIMULATED DESERT POLLUTION CONDITIONS

Semiconducting glazed insulators have advantages of uniform voltage distribution on surface and of keeping the surface dry, which greatly improves pollution withstand voltage. Laboratory tests simulating desert pollution conditions were performed. Test results showed that the semiconducting glazed insulators had the withstand voltage about 2-3 times as high as that of ordinary glazed normal type insulators. The semiconducting glazed insulators are found to have better pollution withstand voltage than silicone rubber insulators. In addition, they showed no corona discharges even at heavy pollution conditions. As a result, the semiconducting glazed insulators can realize high reliability transmission lines in heavy pollution areas at lower cost due to possible compact design and/or less maintenance cost.