500 kV Wujiang substation "replaces core" to increase capacity

The ​500 kV Wujiang Substation Main Transformer Capacity Expansion Project​ in Suzhou has been successfully put into operation. With this upgrade, the ​500 kV Wujiang Substation​ has become the ​largest 500 kV substation in China by transformer capacity, effectively supporting the transmission of clean electricity from western regions to the eastern parts of China and promoting clean, low-carbon development in the Yangtze River Delta.
Located in the western part of Wujiang District, Suzhou, and situated within the ​Yangtze River Delta Ecological Green Integrated Development Demonstration Zone, the Wujiang Substation was commissioned in May 2004. It supplies over ​70% of the electricity demand​ in Wujiang District and serves as a critical power hub in the Yangtze River Delta. The substation also acts as a key node for integrating clean hydropower from the ​Jinping-Sunan ±800 kV Ultra-High Voltage Direct Current (UHV-DC)​​ transmission project into Jiangsu Grid, relying almost entirely on hydropower from western regions to stabilize the regional power grid.
With rapid economic growth in the Yangtze River Delta, electricity demand in Wujiang’s eastern zones has surged, pushing the original three ​750 MVA main transformers​ to their operational limits. To address this, the transformers were upgraded to ​1,000 MVA units, increasing the substation’s total capacity from 5.61 million kVA to ​6.36 million kVA. This expansion enhances annual power supply capacity by ​6.5 billion kWh—equivalent to meeting the annual needs of ​2 million households—and alleviates winter peak-load pressures in the region.
The project involved phased construction, including replacing 56 sets of disconnectors, upgrading automation systems, and implementing rigorous safety protocols. It exemplifies China’s efforts to integrate renewable energy, optimize grid infrastructure, and advance the "dual carbon" (carbon peaking and neutrality) goals through large-scale infrastructure modernization.

Rural Grid Solutions

Unstable Loads & Long Transmission Distances​

​Key Focus: 
Energy efficiency, wide load adaptability, easy maintenance.

​Solutions:
Energy-Saving Designs: Amorphous alloy core transformers (70–80% lower no-load losses) for intermittent loads (e.g., irrigation systems).

​Modular Architecture:
Hot-swappable fault modules to minimize downtime.

​Smart Monitoring: 
IoT-enabled sensors (LoRa/NB-IoT) for real-time load and temperature tracking.Renewable Energy Integration (Solar/Wind Microgrids)​​

​Key Focus:
 Harmonic suppression, voltage regulation.

​Solutions:
On-Load Tap-Changing (OLTC)​: ±10% voltage adjustment to stabilize solar/wind inverter outputs.

​Reactive Power Compensation: Integrated SVGs (Static Var Generators) to limit THD <5%.