MR supports forward-looking power supply in China

Flexible DC transmission with MR tap changers


The development of key technologies for intelligent electricity networks forms part of the National Chinese Development Program for Cutting-Edge Technology. In 2010, an important sub-project for this program was the "Research and development of flexible DC transmission as a connection technology for large wind farms".

Two projects on this subject are currently underway in China: The Nan’ao model project for flexible DC transmission (China Southern Power Grid Company) and the flexible multi-terminal DC project (State Grid Corporation of China) in Zhoushan in the province of Zhejiang. World market leader Maschinenfabrik Reinhausen (MR) provided the on-load tap-changers for these forward-looking projects.

The island of Nan’ao off Shantou is rich in wind resources and was one of the first places selected for wind power projects. It is already home to a vast array of turbines, and flexible multi-terminal DC transmission systems of the ±160 kV voltage class with a transmission capacity of 200 MW have now also been installed. The flexible direct current enables the stable and reliable transmission of large amounts of wind power from the island of Nan’ao. The MR on-load tap-changers ensure stable voltage conditions. China Southern Power Grid Company has opted for proven MR vacuum technology and has ordered two VACUTAP® VM® and one VACUTAP® VR® for the project.

The flexible multi-terminal DC project undertaken by the State Grid Corporation of China in Zhoushan is the world's first flexible DC transmission project with five terminals. The DC voltage is ±200 kV and converter stations are being built in Dinghai, Daishan, Qushan, Yangshan, and Sijiao. Once complete, Zhoushan will have a network for the transmission of DC between the key northern islands, which will improve the electricity connection between the numerous surrounding islands. This will form the basis for tapping into wind power and other new sources of energy. MR has supplied the OILTAP® R, the on-load tap-changer for the highest voltages and the highest currents, for this project.

Through its products and services, MR continues to play a role in the development of the most advanced electricity network in China.

Z.Wang2@cn.reinhausen.com  
Y.Jia@cn.reinhausen.com