This demonstration project started in October 2012, completed in August 2013, the line length of 2 × 648.7 km, through the light of the steel-core aluminum wire winning the project 6236. T . The project is completely designed, manufactured and built by China. It is the first UHV AC transmission project in China and the world. The successful construction and operation of the project is an important milestone in the history of world power development, which is of great significance to promote the scientific development of China's power industry and equipment manufacturing industry, guarantee the reliable supply of power and national energy security.