Research on the Influence Factors of Lightning Performance for ±800kV UHVDC Double-Circuit Transmission Lines

In order to improve the utilization efficiency of the existing transmission corridor, it is necessary to erect two circuits on the same tower. Transmission lines are widespread and easy to be stroke by lightning. Therefore, great attention has been paid to the research of lightning protection for the transmission lines. When two ±800kV transmission line are erected on the same tower, the height of the tower is further increased, and they may be more easily stroke by the lighting. To look for better lightning protection measures, we carried out the research on the influence factors of lightning performance of ±800kV UHVDC double-circuit transmission lines. The conductor type and the spacing between upper and lower line have little influence on the lightning performance, and the influences can be ignored; shielding angle, tower height and ground resistance are the main factors affecting the lightning performance. The research results can provide reference for lightning protection of ± 800kV double-circuit UHVDC line erected on the same tower.