China's first ice-melting substation completes annual full inspection

Power workers carry out maintenance checks at the Qinling ice-melting substation, Shaanxi province. [Photo provided to China.org.cn]

As extreme weather events become more frequent worldwide and energy transition accelerates, grid security and infrastructure resilience have become shared challenges facing all countries. The level of modernization of a country's power sector is measured not only by new technologies and new projects, but also by how it manages critical infrastructure that has been in service for many years throughout its life cycle and responds precisely to extreme operating conditions.

Recently, State Grid Baoji Power Supply Company launched its annual round of comprehensive equipment maintenance inspections. The 110 kV ice-melting substation in the Qinling Mountains — China's first on-load ice-melting substation — has operated safely and continuously for 54 years. Located in northwestern Shaanxi province, this substation offers a window into how Chinese grid companies are safeguarding energy security in the long term and supporting a vital transportation artery.

In winter, the convergence of cold and warm air masses over the Qinling Mountains causes severe ice buildup on power lines. In some sections, the weight of the ice can even cause conductors to sag or break. Two of the lines here not only ensure electricity supply for the mountainous Feng county area, but are also critical to the safe operation of the Baoji-Chengdu Railway — the first electrified railway in China.

On the front line of maintenance, coordinated teamwork are essential to ensuring equipment safety and reliability. During the inspections, maintenance personnel checked, tested and serviced the station's core equipment — a dedicated low-oil circuit breaker commissioned in the 1970s — to ensure its safe and reliable operation. At the same time, specialists carried out a series of secondary system tests, verifications and checks, while synchronous testing was also conducted to fully verify the electrical performance and protection of the equipment.

Zhang Jiaming, safety director of the Substation Maintenance Center at State Grid Baoji Power Supply Company, explained that given the long service life of the station's equipment, the maintenance team developed a dedicated plan. Each procedure and dataset must strictly comply with the regulatory standards to ensure zero defects when entering the winter ice-melting and power-supply assurance period.

For more than half a century, generations of power workers represented by role models such as Mao Tiefu and Zhou Hongliang have put down roots here. Today, Xue Long, deputy head of the Qinling Power Transmission Operation and Maintenance Team and an apprentice of Zhou Hongliang, has taken up the baton and is responsible for the ice-melting substation's operation.

The reliability of power supply is fully demonstrated in each duty shift and task. From October to April, the station is staffed around the clock, monitoring line-icing data in real time and precisely carrying out ice-melting operation instructions. Since it was commissioned, the station has carried out more than 500 load-based ice-melting operations.

With the continual upgrading of the grid, a new ice-melting substation has been included in the plans. As such, this veteran station, which has helped ensure supply for over five decades, is soon to complete its historical mission. State Grid Baoji Power Supply Company will complete this year's annual maintenance checks to a high standard, ensuring the old station continues to operate reliably through the end of its service life, while steadily advancing the planning and construction of the new station. The company's efforts are carrying forward the dedication and responsibility of previous workers, and ensuring the safe and stable operation of the power grid in the Qinling Mountains.

State Grid Shaanxi Electric Power is committed to safeguarding energy security and serving national strategies. It continues to enhance grid resilience and strengthen safeguards for grid security, providing solid power support for local socioeconomic development and the smooth operation of the nation's transportation arteries through professional expertise and technical heritage.