The world’s first transformer, which Siemens developed and manufactured for high-voltage direct-current (HVDC) transmission systems with what is currently the highest transmission voltage of ± 1,100 kilovolts (kV).
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) and shipped to China where the transformer will enable a high-voltage direct-current (HVDC) transmission with low losses over a record distance of 3,284 kilometers with a transmission capacity of 12 gigawatts.
HVDC transformers are part of the converter station that convert alternating current into direct current at the beginning of the transmission line and convert it back again at the end of the line.
The conversion from alternating current to direct current helps to transmit energy over long distances with low losses. Transformers are key components of an HVDC line: Thanks to the transformer, the Changji-Guquan project will be able to transmit direct current with a huge 1,110 kilovolts for the first time in the world.