One of the world's longest transmission links with breakthrough technology
The Xiangjiaba - Shanghai transmission was the first UHVDC (Ultra High Voltage Direct Current) project to go into commercial operation in the world in July 2010. State Grid Corporation of China (SGCC) is the owner and ABB was the main technology supplier. The project was completed in 30 months, one year ahead of schedule.
The ±800 kV Xiangjiaba-Shanghai UHVDC link, with a rated power of 6 400 MW, has the capacity to transmit up to 7 200 MW of power from the Xiangjiaba hydropower plant, located in the southwest of the country, to Shanghai, China's leading industrial and commercial center, approximately 2,000 kilometers away.
The Xiangjiaba - Shanghai transmission link represents a major breakthrough in the technology of electric power transmission in many aspects:
- The new system voltage ±800 kV is 33% higher than the voltage used for the Itaipu ±600 kV transmission in Brazil, until now the world’s highest HVDC transmission voltage rating.
- The power rating, 6 400 MW, surpasses all transmissions in operation today.
- The losses for this long line was reduced to 7% compared with 10% if the line had been built with conventional 500 kV DC transmissions.
- The overhead line length, 1,980 km, is one of the longest overhead transmission links in the world, surpassed only by the over 2,500 km long Rio Madeira HVDC link currently under construction in Brazil. For a long period, the 1,700 km long Inga-Shaba HVDC transmission in Congo-Kinshasa was the world’s longest transmission line.
As part of the turnkey project, ABB was responsible for the overall system design and supply of the main equipment. The scope of delivery included 28 high- and ultrahigh-voltage converter transformers, ten of which were delivered from Sweden and the rest manufactured with ABB components and technology, in local partnership. Other key products delivered include thyristor valves, DC and AC (direct and alternating current) switchyard equipment and the newly developed DCC800 HVDC control system.
| Main data |  |
|---|
| Commissioning year: | 2010 |
| Power rating: | 6 400 MW (7 200 MW) |
| No. of poles: | 2 |
| AC voltage: | 525 kV (both ends) |
| DC voltage: | ±800 kV |
| Length of overhead DC line: | 1980 km |
| Main reason for choosing HVDC: | Long distance |