As China continues to advance its large-scale west-to-east and north-to-south power transmission strategy, Ultra-High Voltage (UHV) transmission has become the backbone of long-distance electricity delivery. At the heart of every UHV transmission project is the transformer—a critical piece of equipment that determines system efficiency, reliability, and operational safety.
CHINT Electric has successfully completed the full routine and type test program for its first self-developed 1000kV/1000MVA Ultra-High Voltage (UHV) AC Transformer, marking a significant milestone in the company's UHV power equipment capabilities. The transformer successfully passed all tests on the first attempt under the witness of experts from authoritative third-party organizations, including the State Grid Electric Power Research Institute (SGRI) Wuhan NARI and Shenyang Transformer Research Institute.
Designed to address the growing demand for high-capacity, low-loss, and highly reliable power transmission, the new transformer provides an advanced solution for modern UHV transmission networks and supports the development of China's new-generation power system.
Addressing Key Challenges in UHV Transmission
As renewable energy integration and interregional power transmission continue to expand, transmission networks face several critical challenges:
- Increasing transmission losses over ultra-long transmission distances
- Growing power demand and renewable energy integration requiring higher transmission capacity
- Stringent reliability and safety requirements for national backbone transmission networks
Building on years of experience in EHV and UHV transformer development, CHINT Electric engineered the 1000kV/1000MVA transformer to enhance transmission capacity, improve operational reliability, and extend equipment service life.
Delivering Industry-Leading Performance
The 1000kV/1000MVA transformer—commonly referred to in China as the "Double Million" transformer—represents the highest voltage and largest capacity currently deployed in AC transmission systems worldwide. It is widely regarded as one of the most technically sophisticated products in power transformer engineering.
Leveraging extensive expertise in extra-high-voltage transformer technology, CHINT Electric optimized the transformer through advanced material selection, structural design improvements, electromagnetic simulation, and comprehensive performance validation.
The transformer successfully passed the complete routine and type testing program on the first attempt and demonstrated outstanding performance across all major technical indicators, exceeding national standards in multiple categories.
Key performance highlights include:
- High-voltage partial discharge: <10 pC
- Medium-voltage partial discharge: <15 pC
- Noise level: <63.7 dB(A)
The product also features low losses, low temperature rise, compact structural design, and high operational reliability.
Technical Advantages
Excellent Insulation Performance
An optimized winding structure improves both main and longitudinal insulation performance while reducing manufacturing complexity and quality risks. The design has been validated through advanced simulation software and successfully passed impulse, induced voltage, and partial discharge testing.
Enhanced Mechanical Strength and Safety
The transformer incorporates an upgraded tank structure and reinforced high-voltage bushing support to improve pressure resistance and mechanical strength. Optimized lead design increases insulation margins and reduces the risk of internal faults, while large-capacity pressure relief devices further enhance operational safety.
High Energy Efficiency
Optimized conductor selection, improved magnetic shielding, refined core manufacturing processes, and upgraded cooling system design significantly reduce no-load and load losses while maintaining exceptionally low operating noise.
Building Comprehensive UHV Manufacturing Capabilities
The successful completion of testing reflects CHINT Electric's long-term commitment to innovation in green power transmission and distribution technologies.
Over the years, CHINT has established a comprehensive power equipment portfolio covering voltage levels from 10kV to 1000kV, forming an integrated industrial platform for high-end, intelligent, and green power equipment manufacturing.
CHINT's Shanghai Transmission & Distribution Industrial Base serves as one of the company's flagship intelligent manufacturing centers, while its Wuhan manufacturing facility specializes in the research, development, and production of 1000kV "Double Million" UHV transformers.
By leveraging the complementary strengths of its Shanghai and Wuhan production bases, CHINT will continue advancing UHV technology innovation and delivering reliable solutions for ultra-high-voltage transmission projects, supporting the global transition toward cleaner energy and more resilient power systems.
Looking Ahead
CHINT Electric will continue investing in advanced UHV equipment technologies, strengthening grid reliability through independent innovation and supporting the development of next-generation power systems with high-performance transmission solutions.
