Suzhou Southern Grid 500kV Unified Power Flow Controller (UPFC)

Suzhou City has the highest gross value of industrial output and at the prefecture-level, is the city with the largest power load and power consumption in China.

This project is the first Chinese 500kV UPFC project with autonomous intellectual property rights. By doing this project, 166 theses have been published and 128 invention patents have been granted or accepted.

This is also the first 500kV UPFC project to adopt modular multi-level conversion (MMC) in the world. MMC technology features small volume, strong controllability, and easy maintenance. It solves the technical defects of past devices and makes full use of the adjustment performance of a UPFC project.

This project makes full use of suburban land resource, avoiding construction of 500kV long line (2x40km), which would cross Tai Lake Ecological Protection Zone, Huishan National Forest Park, and dense urban residential areas, resulting in damage to the ecological environment and relocation of more than 200 households.

Whereas Tai Lake is one of the five largest fresh water lakes in China and cultivates the “home of fish and rice” region south of Yangtze River, the impact of construction of HV line on the Tai Lake environment is not to be under-estimated.

Therefore, this UPFC project perfectly replaces construction of the long line, combining ecological and economic benefits.