State Grid Huai’an Power Supply Company Performs UHV Live-Line Maintenance to Ensure Reliable Summer Power Supply

Recently, inspection personnel from the Transmission Inspection Center of State Grid Huai’an Power Supply Company detected abnormal heating in the strain clamps of the 500 kV Cha’an and Wan’an transmission lines through drone-based infrared thermal inspection.

Line Workers Perform Live-Line Work at High Altitude to Eliminate Overheating Defects on UHV Transmission Lines

As the line serves as a critical energy transmission corridor within Jiangsu Province, its transmission load exceeds 1 million kW during the summer peak period. Since the defect could not be addressed through outage-based maintenance, State Grid Huai’an Power Supply Company promptly developed a live-line work plan and completed safety preparations and technical briefings in advance.

Line Workers Perform Live-Line Work at High Altitude to Eliminate Overheating Defects on UHV Transmission Lines

Before the operation began, the on-site supervisor reiterated work procedures and potential risks to the live-line workers operating at height and jointly inspected the high-altitude work equipment and insulating shielding suits with the team.

After the operation started, the workers used an electric lifting device to climb to a height of more than 50 meters. At that point, the temperature inside their insulating shielding suits had already exceeded 40°C. Facing multiple challenges, including high temperatures, strong electric fields around the energized line, and a confined working area, the workers strictly followed standardized procedures and completed the replacement and tightening of bolts connecting the jumper plate of the strain clamp in an equipotential environment.

Meanwhile, ground safety monitors closely observed the entire operation and ensured effective safety control. After more than one hour of continuous work, the temperature of the equipment returned to the normal range. The defect was successfully eliminated, with the entire operation achieving zero power interruptions, zero impact on customers, and zero safety incidents.

(Authors: Li Yu, Wang Jiahui)