Research on Flashover Voltage of Composite Insulator with Wind Tunnel Test

With the fault of composite insulator, the unidentified flashover fault occupies a considerable proportion, in which the environment factor is more prominent. This paper addresses the analysis of wind tunnel test to simulate the effect of the wind scrapping on insulator, studies the influence extent of different wind velocity and direction on flashover voltage of insulator. At the same time, researches the mechanism of flashover under wind scrapping. In accordance with actual operation condition, the whole test is divided into three type approval test: clean dry condition, dirty dry conditions and artificial pollution. The experimental results show that the flashover voltage always improves with wind velocity increasing regardless of the angle between composite insulators and the wind direction. As to natural environment, the wind would not reduce the normal level of flashover voltage, but can increase the flashover voltage at a certain extent. Especially under fog, rain and other wet conditions, the wind will dry moisture on insulator surface and this can reduce the risk of flashover.