Powering Up An Offshore Giant
For the first phase of the Johan Sverdrup offshore field development, the HVDC-system supplied by ABB has a capacity of 100 megawatts. The power link will operate at +/- 80 kilovolt and is scheduled for operation by year-end 2018.
The decision on whether to opt for AC or DC supply from shore is often dictated by distance. AC cables have a certain capacitance per unit of length. The applied voltage generates so called reactive current due to the capacitance. If the cable is very long, eventually the generated reactive current will equal the rated current of the cable, and at that point no rating is left for useful active current.