A study on streamer discharge characteristics along contaminated insulator surface for different altitude regions

During the pollution flashover process, streamer discharge is a very important stage before arc formation. Study on streamer formation and propagation characteristics along contamination insulator surface under different altitude regions is significant for outdoor insulation design of power transmission and transformation equipment in high altitude regions. In three different altitude cities named Shenzhen, Kunming and Lhasa, the streamer discharge characteristics along contamination insulator surface with different equivalent salt deposit density (ESDD) and non-soluble deposit density (NSDD) were measured on the built insulator contamination research platform, based on a three-electrode structure. The results showed that the variation tendency of stability field for streamer propagation in different altitude regions all fits gauss distribution well, the applied field to obtain the same propagation probability decreases as the increase of altitude and the stable streamer propagation field also decreases as the increase of altitude. At the same time, the applied field to get the same propagation speed decreases and the development of streamer is more easy under the high altitude.