The World's First Live-line Working for +-1100kV Transmission Lines Completed in Anhui

On October 31, in Nangang Town, Shucheng County, Lu'an of Anhui Province, staff of State Grid Anhui Electric Power Company completed the world's first +-1100 kV UHV live-line working 111 meters high above the ground, marking a new milestone for the operation at the +-1100 kV level.

It was reported that during a drone inspection "a clamp pin of the No. 5734 tower along the Jichang-Guquan line had fallen off", which was a hidden defect difficult to be found by manual inspections. It would seriously affect the safe operation of the line without prompt repair.

To solve this problem, an operator wearing a special high-voltage shielding suit sat in a hanging basket and was taken to the site by operators on the tower through lifting machinery. When finished, all operators returned. The whole process took less than 50 minutes.

Wu Weiguo, the leader of the live-line working team of Anhui Power Transmission and Transformation Engineering Co., Ltd, was responsible for this task. The team led by him has broken through many technical bottlenecks in the field of UHV live-line working. "As the Zhundong-Wannan project is the world's first +-1100 kV transmission project, there has been no operation and maintenance experience at home and abroad for reference. Thus, we can only start from scratch and keep making technological breakthroughs." Mr. Wu said.

The +-1100 kV Zhundong-Wannan UHV DC transmission project is the world's most advanced transmission project with the highest voltage level, the largest transmission capacity and the longest transmission distance. With the total length of 3,324km, it runs through Xinjiang, Gansu, Ningxia, Shanxi, Henan and Anhui, transmitting 66TWh of electricity to East China every year.