Asia’s Largest Offshore HVDC Converter Station Completes Major Maintenance
The ±400 kV Huangshayang offshore HVDC Converter Station, recognized as Asia’s largest offshore converter station, has successfully completed a comprehensive scheduled maintenance operation and returned to service, according to a June 24, 2025 announcement. The station, located in Rudong, Jiangsu Province, China, is a hub for offshore wind power transmission and plays a pivotal role in maintaining a stable power supply during peak summer demand.
Scope and Significance of Maintenance
The seven-day maintenance project encompassed not only the offshore ±400 kV Huangshayang Converter Station but also the 220 kV Xiatong and Xiaru Step-up Stations, as well as the onshore ±400 kV Lvgu Converter Station. This coordinated effort was designed to enhance the reliability of the entire offshore wind transmission network, which aggregates power from three major offshore wind farms in Rudong with a combined installed capacity of 1.1 GW.
Industry Impact and Technical Highlights
The Huangshayang facility is the world’s largest offshore flexible DC converter station by both capacity and voltage class. It serves as the central aggregation point for wind power generated by the Rudong H6, Rudong H8, and Rudong H10 wind farms. The station’s annual output reaches 3.3 billion kWh, accounting for nearly 10% of Jiangsu’s offshore wind power capacity and offsetting approximately 5% of the province’s peak summer demand shortfall.
The converter station’s infrastructure is notable for its scale—a six-story offshore platform equivalent in size to a football field and weighing 22,000 tons. Its DC submarine cable, spanning approximately 100 kilometers, is the longest and highest-voltage of its kind in China. The project’s annual output is sufficient to power about 1.36 million households, making a significant contribution to China’s renewable energy and carbon reduction targets.
Operational Leadership and Future Outlook
Chen Yong, Director of the Maintenance Department at Jiangsu Power Transmission and Transformation Company, emphasized the importance of this maintenance cycle: “With an annual power output of 3.3 billion kWh, the station accounts for nearly 10% of Jiangsu’s offshore wind power capacity, enough to offset about 5% of the province’s peak summer demand shortfall”.
The successful completion of this scheduled maintenance underscores the strategic importance of advanced HVDC infrastructure in supporting China’s rapidly expanding offshore wind sector. As the global HVDC market continues to grow, large-scale projects like Huangshayang set benchmarks for reliability, technical innovation, and grid integration of renewable energy
