Ice flashover characteristics of 220 kV anti-icing composite insulator

The decline of the insulation performance of the transmission line caused by the ice-covered insulator strings is an important factor leading to grid fault. Therefore, the electrical performance of an ice-covered 220 kV composite insulator is studied in this paper. Artificial contamination and ice are put on the anti-icing composite insulator. Then the U50% flashover voltage U50% and standard deviation σ50% of the composite insulator are gained and the potential distribution on the ice-covered insulator is measured. The results show that the icicle bridging time of anti-icing insulator is 5 times more than that of the normal insulator while the ice mess is heavier by 0.6 kg/m. Moreover, the U50% and Eh of the anti-icing insulator are higher than those of the normal composite insulator by 11.4% and 7.8 kV/m in the same condition. It is concluded that the umbrella structure of composite insulator can improve the ice flashover characteristics of the insulator.