Abstract:The optical cable repair technology of high-voltage overhead transmission lines directly affects the safe and smooth implementation of repair operations and the reliability of line operation. In view of the critical defects of optical cable breaking caused by lightning strike on 500 kV transmission line of JiangZi line, and considering the special situation that the power grid cannot be cut off for maintenance during the peak summer, the helicopter winch lifting chair operation method is used to successfully realize the repair of the damaged optical cable of 500 kV transmission line. This method adopts the live working mode of ground potential, and uses the new repair mode of "wedge clamp+pure aluminum drainage line" to repair the broken optical cable. By formulating all-round organization, technical and safety measures and emergency plans, the elimination of critical defects of broken optical cable is safely and efficiently completed, which provides a strong guarantee for the safe and stable operation of extra-high voltage transmission lines, and has an important guiding significance and reference value for similar defect elimination of transmission lines.