Abstract: The temporal distribution, the distribution with direction and height at the same spot, and the distribution with altitude and terrain in large region of conductor icing in Southwestern Sichuan province were analyzed by meteorological and mathematical statistics theory based on the observation icing data of Huangmaogeng icing observation station and the investigation information from Ertan-Zigong 500 kV transmission line project, and the micro-topographic features of the heavy conductor icing in Southwestern Sichuan region were summarized. It was found that larger icing density decreases with the increase of altitude and the correspong relationship was established. The research results can provide a reference for professionals engaging in survey, design and maintenance of transmission lines.

Key words: conductor icing, spatiotemporal distribution, Southwestern Sichuan