Ultra-Low Partial Discharge 750kV UHV Transformers for Xinjiang Project

Recently, a Chinese transformer manufacturer independently designed and manufactured six 750kV ultra-high voltage transformers for a 750kV boosting substation project in Xinjiang. All products passed factory acceptance tests and type tests on the first attempt, obtaining KEMA type test reports. Testing confirmed that all performance indicators exceed national standards and technical agreement requirements. Notably, the high-voltage partial discharge is only 8pC and the medium-voltage partial discharge is only 12pC, achieving an ultra-low partial discharge level.

The Chinese transformer manufacturer employed innovative design concepts and advanced development technologies, conducting in-depth research on multiple key technologies including overall structure, main longitudinal insulation, and short-circuit withstand capability. The products feature a single-phase, three-limb design with side-column voltage regulation structure. The insulation system adopts a zero partial discharge design to ensure exceptional insulation performance. 

For electromagnetic and thermal challenges, the products utilize unique electromagnetic composite shielding technology to effectively resolve related issues. For the 750kV high-voltage leads, more advanced built-in formed lead devices and direct tank cover outlet methods were implemented. Additionally, through creative improvements in bushing selection, tank structure, and non-electrical protection systems, traditional design drawbacks were circumvented, significantly enhancing the products' explosion-proof capabilities. Furthermore, considering Xinjiang's extreme operating environment with large diurnal temperature variations and severe sandstorms, the team optimized conservator tank specifications, cabinet (door) structures, and component selection to ensure long-term operational safety and reliability.

The successful R&D and mass production of these products marks a significant breakthrough for Chinese transformer manufacturers in the field of large-capacity, ultra-high voltage transformer development. In the future, we will continue to strengthen our core capabilities in power transmission and transformation technology, driving development through innovation and contributing greater efforts to advancing power technology worldwide.