HVDC > HVDC Classic > What is HVDC > Multi-terminal systems
A multi-terminal HVDC transmission is an HVDC system with more than two converter stations.
A multi-terminal HVDC transmission is more complex than an ordinary point-to-point transmission. In particular, the control system is more elaborate and the telecommunication requirements between the stations become larger.
There is only one large-scale multi-terminal HVDC system in operation in the world today. It is the 2,000 MW Hydro Québec - New England transmission built by ABB between 1987 and 1992. The operating experience of this transmission is very good and has proved that from a technical point of view there are no problems to connect several converter stations to the same HVDC transmission line.
The HVDC Light technology makes multiterminal systems a lot easier since it is no need to balance the currents like in “conventional multi-terminal” HVDC.