USA

ABB has been awarded the $50 million contract to install an HVDC link between the eastern and western power grids of the US.

ABB will design, build and install the system, a joint project between two US utilities, Basin Electric Power of Bismarck, North Dakota, and Black Hills Power, of Rapid City, South Dakota.

The HVDC system, to be called the "Rapid City Tie" owing to its proximity to Rapid City, S Dakota, will increase the capacity for high voltage power exchange between the two grids by 200 MW.

ABB are to deliver the system in 19 months; the Rapid City Tie is scheduled to enter commercial operation in October 2003. Besides enabling east-west power trransmission, it will also provide voltage and frequency support for disturbances in either one of the grids. It must also reconcile the unsynchronised nature of the east and west systems.