The construction of Zhangbei Flexible DC power grid, the world's first flexible DC power grid, began on February 28. The project connects northern Hebei with Beijing, with a total investment of 12.5 billion yuan. After the completion of the project, it will effectively promote the transmission and consumption of new energy in Hebei, and provide stable and reliable clean electricity for the Beijing-Tianjin-Hebei region.

The rated voltage of the project is ±500 kV, and the total commutation capacity is 9 million kilowatts, which is also a flexible DC project with high voltage level and large transmission capacity in the world. The project will build 666 kilometers of DC transmission lines, and build four new converter stations in Zhangbei, Kangbao, Fengning and Beijing to ensure that all of them are completed and put into operation in the first half of 2020.

The so-called flexibility mainly refers to the flexible operation control and high degree of intelligence. Compared with traditional technologies, flexible DC transmission can improve the stability of the power system, support the access and large-scale delivery of new energy under the condition of "weak transmission end", and improve the reliability and flexibility of the distribution network. Just like a tai chi master, it has the ability of "overcoming hardness with softness" and is the cutting-edge technology in the field of power grid science and technology.

As a national renewable energy comprehensive demonstration zone, Zhangjiakou in Hebei Province is very rich in wind and solar energy, with an installed capacity of more than 10 million kilowatts, and plans to exceed 20 million kilowatts in 2020, but the local consumption capacity is obviously insufficient.

"The construction of Zhangbei flexible DC project will realize the connection between Zhangbei new energy base, Fengning energy storage power supply and Beijing load center." By then, the proportion of electricity generated outside Beijing will reach 70 percent, and the Winter Olympic venues will be powered by 100 percent clean energy, effectively serving the construction of a low-carbon Olympic zone." Said Shu Yinbiao, chairman of the State Grid Corporation.

The core technology and key equipment of Zhangbei flexible DC project are the first in the world, and will achieve 12 world one. The project will promote the innovative development of flexible DC transmission technology in higher voltage level and larger transmission capacity. The formation of a set of Chinese solutions will play an important role in improving the independent innovation capacity and international competitiveness of China's electrical equipment manufacturing industry, and maintaining and expanding China's advantages in the global power field.

(This article comes from the network, only for technical communication)