Safety analysis of live working on 35kV line in high altitude area

The 35kV line is an important part of China's distribution lines and has the characteristics of larger transmission capacity and lower line loss than 10kV distribution lines. However, its live work is rarely carried out, especially the lack of key parameters such as the required safety distance and insulation shielding requirements for live work on 35kV lines in high altitude areas, which limits its further improvement in power supply reliability. In this paper, through the small gap operation impact discharge test in Yangbajing (4300m), Lhasa (3600m), Linzhi (2900m) and Wuhan (28m) and other regions, the corresponding discharge characteristic curve was obtained. Then apply the insulation coordination practice of live working. The minimum electrical safety distance for 35kV live working at high altitudes above 2500m is calculated by conventional usage, and the DU is rounded to 50cm. The method of working with insulated gloves is DE=0.2m. When the method of working with insulated rods is used, DE=0.6m. Combined with the typical 35kV pole tower structure, when conducting live work in high altitude areas, the operator should not enter the area between the insulator and the pole tower. The effective protection area of the insulation shielding tool is from the central area of the shielding tool surface to the edge of 20 cm from the area above 2500m as shown in the figure.