State Grid Corporation of China workers install and commission an automatic ground wire de-icing device at Tower 1 of the 110kV Sili line in Wulong district, Chongqing. [Photo provided to chinadaily.com.cn]
Xue Xiaoxiong, an employee of the State Grid, along with his colleagues, visited Tower 1 of the 110 kV Sili line to conduct the initial inspection of the ground wire ice melting automatic wiring device mounted on the tower on Nov 25. Recently, the first set of ground wire ice melting automatic wiring device from the State Grid Chongqing Electric Power Company was commissioned there, laying the foundation for ice melting on this line during icy and snowy weather.
Towers 1 to 5 of the 110 kV Sili line are situated at Siyuanping in Heshun town, Wulong district, Chongqing, at an elevation of over 1,700 meters. Located in a severe 30mm ice-covered zone, this segment of the line experiences heavy icing every winter, necessitating timely de-icing operations. Previously, de-icing of the ground wire in this section was primarily carried out using unmanned aerial vehicles.
The ground wire deicing automatic wiring device that has been put into operation consists of the device body, a visual monitoring module, and a remote control module. The device body primarily comprises an offset correction component, a rotating conductive rod component, and a dynamic and static contact component.
When the ground wire icing thickness of No 1 to No 5 towers on the 110 kV Sili line reaches the ice melting threshold, operation and maintenance personnel simply need to press the start button in the control box beneath the tower to activate the motor, which in turn drives the conductive swing rod. Through visual positioning, the connection between the ground wire and the conductor can be completed within 5 minutes. This allows the current from the DC ice melting device in the substation to be directed into the ground wire, utilizing the thermal effect generated by the current to melt the ice on the ground wire. Once the ice melting process begins, when the ground wire current reaches 180A, the ground wire temperature rises to 30℃, causing the ice on the ground wire to melt and fall off within 1 hour.
In addition, during the de-icing of line ground wires, operation and maintenance personnel can utilize both the icing monitoring device and the ground wire de-icing status monitoring device to continuously track the de-icing progress in real time. This ensures comprehensive monitoring of the entire ice observation and de-icing process, forming a closed-loop system, thereby enhancing the line's disaster resistance and safe operation capabilities.
Next, State Grid Chongqing Electric Power will monitor and evaluate the operation of the automatic ground wire deicing device, and promote its application when conditions are ripe. Meanwhile, the company will diligently carry out ice observation and melting for power transmission and distribution lines in the supply area, fully prepare for rain, snow, and freezing weather, and ensure the safe operation of line equipment during the winter peak season.
