Under the high altitude short tail shock 220 kV composite insulator flashover characteristics research

The flashover characteristics of insulators is one of the important indexes to evaluate the lightning resistance performance of transmission lines, but it is difficult to carry out lightning flashover tests for all kinds of insulators in real towers, and the difference of flashover characteristics between insulators in real towers and single insulators is not clear. At the same time, when lightning strikes back, the criterion of insulator flashover based on the standard lightning impact has certain limitations. Aiming at the situation of composite insulator of 220kV line without pressure balancing ring, pressure balancing ring at high-voltage end and pressure balancing ring at both ends, this paper compared the test results of U
50%
and volt-second characteristics of high altitude real tower (drum tower and umbrella tower) and a single 220kV composite insulator under short tail wave impact. The flashover characteristics of 220kV composite insulators was analyzed according to the discharge path captured by high-speed camera.