DC transmission lines crossing heavy ice sections are susceptible to icing hazards and insulator ice flash tripping faults. In this paper, a new type of ±500kV DC heat-absorbing anti-ice flash composite insulator was developed by combining heat-absorbing anti-ice material and insulation skirt outer insulation structure optimization design. The new anti-ice flash composite insulator and the common anti-ice flash composite insulator specimens were subjected to live ice cover and ice flash test in the artificial climate laboratory. The test results show that the ice thickness and icicle length of heat-absorbing anti-ice flash composite insulators are always smaller than those of common insulators under the same ice covering time; the ice flash voltage of heat-absorbing and common anti-ice flash composite insulators decreases with the increase of ice thickness and ice covering water conductivity, but the former is always higher than the latter. The test results can provide technical guidances for the anti-icing design of DC transmission lines in heavy ice areas.

Anti-icing flashover composite insulator;DC Transmission Line;Icing Accretion;Flashover Characteristics