Here is the world’s first ±1,100 kV transformer, developed and manufactured by Siemens for a high‑voltage direct current (HVDC) transmission project in China.
This HVDC transformer was developed, manufactured, and tested by Siemens at its transformer plant in Nuremberg. It is the first of a total of seven ±1,100 kV transformers that Siemens and a partner company are building for what is currently the largest HVDC transmission system in the world. It also represents the highest transmission voltage ever built to date.
This type of transformer is a single‑phase unit with a power transmission capacity of 587.1 MVA. The transformers are manufactured within Siemens’ network of facilities in Nuremberg, Germany.
The Most Powerful HVDC Transmission System in the World
The HVDC link will be operated by the public transmission system operator State Grid Corporation of China (SGCC). The planned 1,100 kV HVDC transmission line connects the cities of Changji (Xinjiang) and Guguan (Anhui) in China.
This project is currently the most powerful HVDC transmission system in the world. It spans a distance of 3,284 kilometers and has a transmission capacity of 12 gigawatts (GW).
What Is HVDC (High Voltage Direct Current)?
High Voltage Direct Current (HVDC), known in French as courant continu haute tension (CCHT), is a power electronics technology used to transmit electricity at high voltage using direct current.
HVDC transmission is less common than traditional alternating current (AC) transmission in electrical power grids. However, its primary advantage is the ability to transmit electricity over very long distances with lower energy losses.
This makes HVDC technology particularly well suited for long‑distance transmission projects, interconnections between power grids, and the integration of large‑scale renewable energy sources.