Wet snow flashover characteristics of the insulator strings in “ Λ “ Shape on 500 kV transmission lines

In order to study the wet snow flashover characteristics of the insulator strings in “Λ” shape on 500kV transmission lines, several wet snow flashover tests were taken in the large artificial climate chamber of China Electric Power Research Institute. The final flashover voltages were got by uniform step-up method and the video camera in chamber recorded the process of wet snow flashover. This results shows that installing anti-icing shed which has the larger diameter can increase the wet snow flashover voltage; There is an optimal angle in “Λ” shape of insulators strings. It doesn't have a good performance in anti-flashover when the angle is too small, but the too large angle will short the insulation distance.