What progress has been made in China's ultra-high voltage transmission technology?

On June 6, 1972, the Longyangxia-Tianshui-Guanzhong 330-kilovolt AC transmission line was completed and put into operation, which was the highest level of construction in China's high-voltage transmission field at the beginning of the reform and opening-up period. After China's transmission line voltage upgrade, Zhang Guobao said that in 1981, through a full set of imported equipment and technology, China built the first 500 kV AC transmission line, that is, the line from Henan Pingdingshan to Hubei Wuchang. 3 years later, on the basis of the introduction, digestion and assimilation of foreign technology, China built the first self-designed and constructed Yuanjin Liaohai 500 kV AC transmission line, that is, from Yuanbaoshan Power Plant through Hubei Wuchang, China built the first 500 kV AC transmission line, that is, from Yuanbaoshan Power Plant through Hubei Wuchang, China built the first 500 kV AC transmission line. In 1989, China's first ±500 kV DC transmission line, Gezhouba-Shanghai Ge-Shanghai DC, was put into operation, followed by a steady increase in the transmission level. After that, the transmission level was steadily increased, reaching 750 kV in 2005, and the first 1,000 kV UHV transmission line was put into operation in 2009. China's power grid took a big step into the era of ultra-high voltage.

The year 2010 is the harvest year of China's UHV technology and construction. 18 June, the national "Eleventh Five-Year Plan" key construction projects and DC UHV transmission demonstration project of autonomy Yunnan - Guangdong ± 800 kV UHV DC transmission project, double-pole put into operation, which is the first time in China's power grid in the era of UHV. Project, bipolar put into production, which is the world's first high-altitude, long-distance, high-capacity transmission line, marking China's electric power technology, equipment manufacturing to reach the international advanced level. About 20 days thereafter, the Xiangjiaba - Shanghai ± 800 kV UHV DC transmission demonstration project was put into operation, which is independently developed, designed and constructed by China, and is the world's DC transmission project with the highest voltage level, the largest transmission capacity, the furthest distance of power transmission, and the most advanced technology, and it is a world-class innovative achievement made by China's energy field. It is a world-class innovation achievement in China's energy field and represents the highest level of high-voltage DC transmission technology in the world today. The UHV DC transmission demonstration project is the first in the world to realize a double increase in DC transmission voltage and current, and a double breakthrough in transmission capacity and power transmission distance.

Since then, the pace of UHV line construction has accelerated. At present, 21 UHV projects have been completed, with a line length of 38,000 kilometers and a transmission capacity of over 140 million kilowatts. At present, the line length of 3324 kilometers ± 1100 kilovolts Xinjiang Jundong - Anhui Wannan ultra-high voltage direct current transmission line is under construction, completed and put into operation, the line will set a number of ultra-high voltage world record.

China's electric power science and technology workers with a practical and enterprising spirit of innovation, and constantly realize China's ultra-high voltage technology breakthroughs, won one honor after another, especially "ultra-high voltage AC power transmission key technologies, complete sets of equipment and engineering applications," "ultra-high voltage ± 800 kilovolt DC transmission project" two innovative achievements. Engineering", two major innovations won the National Science and Technology Progress Grand Prize in 2012 and 2017 respectively. Grid companies have achieved outstanding results in the fields of extra-high voltage, smart grid, flexible DC transmission, safety control of large power grids, and new energy grid connection, and have won a large number of patents and science and technology awards. Source: People's Daily