Recently, maintenance and inspection personnel from China’s State Grid Qinghai Electric Power Company successfully carried out an ultra-high voltage live-line operation near the Tanggula Mountain Pass at an altitude of 5,211.5 meters. They eliminated defects in the Qinghai-Tibet Interconnection Project’s ±400kV Chaila DC transmission line, consolidating the power supply security for Tibet during the Spring Festival.
The maintenance site had an oxygen content of only 40% that of the plains, with temperatures dropping to minus 20°C. Staff adopted a combination of “drone + electric lift” technology to efficiently complete the defect repairs.
This operation set a new world altitude record for ultra-high voltage live-line work and marked China’s first such operation in a 5,000-meter-class high-altitude region. As the “Power Sky Road” linking Qinghai and Tibet, the Qinghai-Tibet Interconnection Project has, since its commissioning at the end of 2011, solved the problem of power shortages in Tibet during winter and the difficulty of utilizing hydropower in summer. The Chaila DC segment has an average altitude exceeding 4,000 meters, making maintenance extremely challenging. This operation has demonstrated