“With successful testing of the world’s first HVDC transformer for a transmission voltage of ± 1,100 kilovolts, we have set a new benchmark in direct-current transmission,” states Beatrix Natter, CEO of Power Transformers at Siemens Energy Management. “Experience and ingenuity are what made this development possible. It makes direct-current transmission over long distances more efficient for our customers, because higher transmission voltages mean lower transmission losses.”
The transformers will be installed in the Guquan converter station of the HVDC link between the Chinese cities of Changji (Xinjiang) and Guquan (Anhui). This is the world’s most powerful HVDC transmission system in terms of transmission capacity, voltage and length. It will transmit power with a DC voltage of ±1,100 kV for the first time anywhere in the world. The HVDC link is 3,324 kilometers long and will transmit electricity from the northwestern Xinjiang region to Anhui Province in eastern China. With a transmission capacity of twelve gigawatts (GW), it will replace what was previously the most powerful system with a capacity of 10 GW. In these systems, the transformers are used to feed power from conventional AC transmission grids into so-called converter stations. These generate the DC voltage on one side and convert it back to AC voltage on the receiving side. Due to the type of connection to the converters, the transformers will also be loaded with the very high DC quantities of the transmission voltage and current.
Based on many years of experience with HVDC transformers, Siemens further developed all key components of this type of transformer, thus reaching a new transmission level in HVDC technology. The workflows for manufacturing and testing this product were challenging due to the transformer’s extreme dimensions (LxWxH: 37.5 m x 12.0 m x 14.5 m). Nevertheless, the ±1,100 kV prototype was able to pass every test in terms of functionality, emissions and load level. The type-tested HVDC transformer is now being prepared for its long journey to China by road and sea.
Further information on Siemens-HVDC-Transformerswww.siemens.com/transformers
For further information on Division Energy Management, please see www.siemens.com/energy-management