Study on ac artificial-contaminated flashover performance of various types of insulators

Artificial pollution tests have been carried out to study ac flashover performances of various types of porcelain, glass, and polymeric insulators in this paper. The experimental results show that the polluted flashover voltage [U.sub.f] is affected by equivalent salt deposit density [[rho].sub.ESDD] and nonsoluble deposit density [[rho].sub.NSDD], the influences of which are independent of each other. Based on the analyses of the flashover voltages, the correction formulas of the flashover voltages [U.sub.f] of various insulators at various [[rho].sub.ESDD] and [[rho].sub.NSDD] levels are pointed out. The experimental results also show that there is a distinct difference among the flashover voltages of various types of polluted insulators. At the same pollution degree, the antipollution performance of the fog-type glass insulator is better than those of the outer-rib porcelain insulators. In terms of the effectiveness of creepage distance of insulators, the antipollution performance of polymeric insulators is superior to those of porcelain and glass insulators. Index Terms--[[rho.sub.ESDD], [[rho].sub.NSDD], ac, artificial pollution test, flashover performance, insulator, shape.