Replacing Construction Technology of Corroded Ground Wire of 500 kV Line Across Three 220 kV Transmission Lines in the Same Gear

[Introduction] With the increase of operation time of overhead transmission lines and the aggravation of aging and corrosion of equipment, the rusted ground wire replacement is significantly increased. Due to the large cross span of overhead transmission lines and the decrease of mechanical properties of corroded ground wires, there is a high risk in the replacement construction, especially when the same grade crosses multiple high-voltage power lines. Therefore, it is necessary to explore the methods, steps and safety precautions of replacement construction. [Method] Taking the replacement construction of corroded ground wire of a 500 kV transmission line spanning three 220 kV power lines in the same span from Pingguo to Laibin as an example, in order to reduce the risk in the replacement process, the measures were taken, such as wire sealing, two-way protection of steel wire rope installed on the ground wire support, reasonable setting of the traction field, reducing the traction speed of the ground wire and reclosure of the crossing line one by one. [Result] These measures are verified to be safe and effective on site, which can well protect the safety of the power lines across and reduce the risk of construction operations. [Conclusion] These key technologies in construction have important reference significance for future similar operations.