Summer is the thunderstorm weather season, coupled with the summer is the peak power season, in the event of a lightning strike wire line, resulting in power outages, will greatly affect people's safety and quality of electricity. However, for a long time, the disconnection of the insulated conductor by lightning has been a difficult problem that plagued the operation of the distribution line. After the insulated conductor is struck by lightning, the lightning current is found to release the lightning current at the nearest release point of the line, and the high- Cause a disconnection accident. According to this principle, in recent years, a series of lightning protection measures against lightning strikes have been used in wire lines, such as direct-coupled zinc oxide arresters and mutual-surge arresters. These measures are lightning arrestors installed on the insulator of the wire line lightning protection, as soon as possible through the arrester shunt release discharge caused by lightning, has played a certain role, but the lightning will inevitably hit the wire line, causing the line Trip accidents, seriously affecting the reliability of distribution lines and continuous power supply, to explore effective lightning protection measures imminent. Recently, Nantong Electric Power Design Institute designed the top of the wire line to install a single lightning line lightning protection measures. The lightning conductor is arranged in parallel above the conductor. Each point of the conductor corresponds to a protection range of 30 degrees below the conductor. The advantage lies in that the lightning strike no longer directly bears on the conductor, but rather runs on the conductor above the conductor, Direct shunt wire lightning generated electricity, effectively enhancing the power supply reliability of the wire. At present, the lightning protection pilot program of this wire line has been coordinated and supported by the technical management staff of Nantong Power Supply Company, and will be carried out in "20kV Hengshan line 425001 # 425027 # pole insulated maintenance" and "20kV sea Line 42001 # ~ 42028 # pole insulation repair "project put into effect, and is expected to finish construction in the peak summer. Once the lightning protection effect of this technology has been confirmed, it will provide powerful technical support for the improvement of lightning protection technology of low voltage insulated wire in Nantong area.