On December 27, 2024, the Sichuan-Chongqing UHV AC Project, the first AC UHV project in the southwest region, which China Energy Construction Southwest Engineering Institute participated in the survey and design, was officially put into operation.
The Sichuan-Chongqing UHV AC project is a key project in China's "14th Five-Year Plan" power development plan, with a total investment of 28.631 billion yuan. As China's first high-altitude UHV AC project, the project is a landmark project following the 1000 kV UHV AC test demonstration project in Southeast Shanxi-Nanyang-Jingmen. The project passes through eight cities (prefectures and districts) including Ganzi Prefecture, Ya'an City, Meishan City, Leshan City, Neijiang City, Ziyang City in Sichuan and Tongnan District and Tongliang District in Chongqing, and newly built 1000 kV lines of 1,316 kilometers. The project has built four 1000 kV substations in Ganzi, Tianfu South, Chengdu East and Tongliang in Sichuan and Chongqing, with a total substation capacity of 24 million kVA.
Among them, a new 1000 kV substation in Ganzi and a 127.964 km line were built. The substation stands proudly at the top of a high altitude, and the line winds from Luding in Ganzi to Tianquan in Ya'an, with a thickness of 60 mm of heavy ice, which has set a new record for China's AC UHV projects.
Ganzi 1000 kV Substation
The Ganzi 1000 kV substation is located on a plateau at an altitude of 3,450 meters and with an earthquake intensity of 8 degrees. It is the first time that a UHV AC project has entered a high altitude area. Faced with an extremely harsh construction environment, the design team of China Southwest Power Engineering Institute successfully overcame multiple challenges and completed the survey and design of the main control and communication building, GIS room, main transformer assembly plant and auxiliary systems, creating many bests.
Design highlights
·Application of high-altitude UHV AC disassembly transformer: The disassembly transformer was applied in high-altitude areas for the first time, and on-site assembly was achieved.
·Air gap value of high-altitude substation: The air gap design of the world's first high-altitude 1000 kV substation.
·GIS room and frame design: The first design of a high-altitude GIS room and a maximum span frame in China.
·Six-split conductor technology: The six-split conductor was used for the first time in a high-altitude 1000 kV power station, and passed the corona field strength assessment.
·Equipment selection and general layout: The equipment selection and general layout design of the high-altitude 1000 kV substation were completed.
·Seismic technology: Seismic isolation and shock absorption technology were applied in high-altitude equipment to meet the seismic requirements of 9-degree earthquakes.
·Pricing system: The pricing system of the high-altitude 1000 kV substation was completed, and the adjustment basis based on the new version of the regulations was proposed.
·Tibetan aesthetic architectural style: Tibetan elements were integrated into the design of UHV substations to highlight regional characteristics.
