Core Viewpoint - The development of UHVDC (Ultra High Voltage Direct Current) technology is becoming a significant aspect of China's international presence, with companies like Borui Electric leading the way in overseas projects [1][2]. Group 1: UHVDC Technology and Projects - UHVDC technology is crucial for large-capacity, long-distance power transmission and interconnection of power grids, widely applied in major domestic and international projects [2]. - China has completed 23 UHVDC projects domestically, with Borui Electric supplying core equipment for 19 of them, including the world's highest voltage level project, Changji-Guquan ±1100kV UHVDC project [3]. - Borui Electric has established a strong reputation internationally, attracting many countries to choose Chinese manufacturers for UHVDC projects, as seen in the Brazil Belo Monte Phase II ±800kV UHVDC project [3][4]. Group 2: International Expansion and Innovations - Many countries are opting for Chinese manufacturers for the renovation of existing UHVDC projects, such as Borui Electric's first overseas UHVDC converter valve renovation project at Brazil's Itaipu Hydropower Station [4]. - Borui Electric and other companies from Changzhou are promoting "Changzhou manufacturing" globally, further solidifying Changzhou's position in the UHV transmission and transformation equipment manufacturing sector [4]. Group 3: Flexible DC Technology - The increasing share of renewable energy in the power grid poses challenges for stability, leading to the emergence of flexible DC transmission technology [5]. - By 2025, it is projected that wind and solar power installations in China will reach approximately 1.65 billion kilowatts, accounting for 46% of total power installations, necessitating UHVDC for long-distance transmission [5]. - The world's first UHV flexible DC project, Gansu to Zhejiang ±800kV, began construction in July 2024, with Borui Electric participating in the world's largest flexible DC back-to-back project in Dongguan [6]. Group 4: Future Developments and Innovations - Borui Electric is accelerating the development of grid-forming energy storage systems, intelligent pumped storage, and flexible low-frequency transmission technologies to support the new power system [6]. - The company has successfully developed grid-forming energy storage and other technologies, which are essential for the rapid development of new power systems [6].

Core Viewpoint - The Ningxia to Hunan ±800 kV UHVDC transmission project, known as "Ningdian Ruxiang," has been fully commissioned, with a maximum transmission capacity of 8 million kW, capable of delivering 36 to 40 billion kWh of electricity annually to Hunan [1] Group 1: Project Overview - The project spans 1,616 kilometers, starting from Zhongning Converter Station in Ningxia and passing through Gansu, Shaanxi, Chongqing, and Hubei before reaching Hengyang Converter Station in Hunan, with a total investment of 28.1 billion yuan [1] - The project faced significant challenges due to its long distance and complex geographical environment [1] Group 2: Key Equipment - High-end converter transformers, regarded as the "heart" of UHVDC projects, play a crucial role in the conversion of AC to DC and in voltage and power regulation [1] - The Hengyang Converter Station features 14 high-end converter transformers independently designed and manufactured by TBEA, marking a significant achievement in domestic production capabilities [1] Group 3: Technological Advancements - TBEA enhanced the manufacturing precision and reliability of the transformers by reducing the number of welding points from over 450 to 42, improving reliability by tenfold and significantly increasing short-circuit resistance [2] - The transformers were designed to maintain a temperature rise below 35K, compared to the industry average of 40K, thereby extending their operational lifespan [2] Group 4: Supporting Infrastructure - The Zhongning Converter Station was custom-designed with earthquake-resistant epoxy resin impregnated paper capacitive DC bushings to ensure safe operation in a seismically active area [3] - TBEA upgraded traditional manufacturing processes to high-precision CNC plasma cutting systems to meet the high stability requirements for transformer oil tanks [3] - Innovative steel core aluminum stranded wire products were developed using an intelligent production system, enhancing production efficiency and ensuring high-quality conductors with micron-level precision [3]

Core Viewpoint - XJ Electric emphasizes the advantages of UHVDC (Ultra High Voltage Direct Current) transmission, highlighting its low loss, flexible control, and system stability in long-distance power transmission applications [1] Company Summary - XJ Electric's UHVDC products, including conventional and flexible DC transmission converters and control protection systems, are utilized in multiple UHV lines across the country [1]

Core Insights - The State Grid DC Technology Center has developed a high-performance impregnated paper insulation technology for ultra-high voltage converter transformer bushings, achieving international leadership and recognized as a world-first innovation [1][2] Group 1: Technology Development - The new technology replaces traditional oil-immersed paper insulation with impregnated paper, eliminating safety hazards such as abnormal gas generation and reducing the risk of porcelain bushing explosions [1][2] - The project team overcame key technical challenges related to large-size core materials, design, and processes, establishing a complete independent intellectual property technology system [2] Group 2: Performance and Application - The new impregnated paper bushings have surpassed existing insulation levels, partial discharge levels, and current-carrying capacity, with strict testing criteria [2] - As of now, 258 units of 550kV and 800kV bushings have been successfully applied in engineering, with 154 units in operation showing zero defects [2] Group 3: Industry Impact - This breakthrough addresses technical bottlenecks in DC safety operation, providing strong support for the construction of ultra-high voltage projects during the 14th Five-Year Plan [2] - The development is significant for promoting energy technology revolution and aiding in achieving carbon neutrality goals [2]

Core Viewpoint - The "Jiangdian into Chongqing" project, part of China's "14th Five-Year Plan," has successfully commenced power transmission, utilizing over 70% renewable energy from a 14.2 million kilowatt power source [1][6]. Group 1: Project Overview - The "Jiangdian into Chongqing" project connects five provinces and municipalities, spanning 2,260 kilometers, and has achieved operational status in under two years, setting a record for the fastest construction of a high-voltage transmission line over 2,000 kilometers in China [2][4]. - The project leverages unique wind and solar resources in the arid regions of Xinjiang, with the local area currently utilizing less than 5% of its renewable energy potential [6][15]. Group 2: Technical Challenges and Solutions - The construction faced significant challenges due to complex terrains, including snow-capped mountains and deserts, with winter temperatures in Xinjiang dropping to -30 degrees Celsius [5]. - To ensure stability in high-wind areas, the construction team reinforced transmission towers in regions with wind speeds reaching level 10, enhancing the safety of the power lines [5]. Group 3: Environmental Impact - The project is expected to deliver 36 billion kilowatt-hours of electricity annually to Chongqing, with a clean energy ratio of at least 50%, resulting in a reduction of 16.5 million tons of CO2 emissions each year, equivalent to planting 900 million trees [7][15]. Group 4: Technological Aspects - The project employs a ±800 kV high-voltage direct current (HVDC) system, allowing electricity to travel from Xinjiang to Chongqing in just 7 milliseconds, significantly improving the cross-regional consumption of clean energy [8][10]. - The Chongqing converter station, covering 27 hectares, utilizes advanced technology for monitoring and maintaining the core components, ensuring efficient conversion from direct current to alternating current for household use [12][14]. Group 5: Economic Significance - The "Jiangdian into Chongqing" project enhances the energy structure of Chongqing, providing enough electricity for 10 million households annually, and supports the economic development of both Xinjiang and Chongqing [15].