Abstract：Zinc oxide lightning arresters are widely used in power transmission and transformation systems due to their excellent non-linear volt-ampere characteristics. They are the main protective devices to protect power equipment from overvoltage damage. This study introduces a 500 kV zinc oxide lightning arrester fracture fault. Through the analysis of the line fault recording files and the stress on the connection terminal board, the fault occurrence sequence and cause are determined. Since the arrester adopts a wiring form where a long lead is directly connected to the outgoing line, and the voltage transformer is arranged on the outside, and the diameter of the arrester is relatively small, the arrester is subjected to a large wire pulling force in windy weather, resulting in the fracture of the arrester. To avoid similar faults, the connection mode of the down conductor is renovated in combination with the on-site situation, connecting the down conductor of the transmission line directly to the top terminal block of the voltage transformer. This method is simple and convenient for engineering application.
2025, Vol. 26 
