State Grid Shaoxing refurbishes substation to bolster winter grid resilience

State Grid Shaoxing Power Supply Company has completed the comprehensive refurbishment of the 220-kV Shuangqiao Substation ahead of Spring Festival, marking a strong start to its annual maintenance schedule.

The return to service of the 110-kV auxiliary bus and associated equipment concluded the project, which was executed within a single outage window through integrated planning. The upgrade significantly strengthened the substation's cold-weather resilience, reinforcing the stability of Shaoxing's power grid for the year ahead.

Located in Zhuji's Huandong subdistrict, the substation has supported local economic growth since its commissioning in June 1999. In response to persistent cold weather, the maintenance campaign prioritized livelihood protection and operational safety.

A phased approach enabled crews to complete multiple critical tasks within the planned outage, including replacement of 12 aging current transformers and surge arresters, degassing of the No 2 main transformer, and C-level inspections covering 74 units across 32 bays.

The project also addressed six hidden hazards, implemented five countermeasure upgrades, and carried out seven refinement enhancements.

Winter-proofing measures were central to the operation. The team degassed the No 2 main transformer, applied sealant to top bolts of surge arresters and voltage transformers, and reinforced terminal boxes to improve moisture resistance.

Outdoor disconnector mechanisms were lubricated, cleaned, and debugged. Defects such as incomplete closure and jamming in multiple grounding switches — including those on the Shuanghongxian and Qiaogaoxian lines — were rectified.

All suspension insulators were manually inspected to eliminate potential detachment risks, ensuring stable equipment performance under extreme icy conditions.

State Grid Shaoxing reaffirmed its dedication to public service, stating that it will continue advancing core equipment upgrades and hazard elimination through refined maintenance.

These efforts aim to ensure grid safety and provide a stable power supply for residents and key users during the festive season.