North Sea Wind Power Hub Feasibility Study: AC and DC Interconnection Comparison (Part III)

An innovative concept of hub-and-spoke has been proposed by North Sea Wind Power Hub consortium to combine electricity transmission from wind farms to shore with interconnectors. The hub-and-spoke are based on elementary block types in bipolar configuration at rated voltage of 525 kV with dedicated metallic return and are used in association to build the distributed hub scenarios. In this paper, two internal interconnector (II) solutions, namely DC II and AC II, are compared and examined. A focus is placed on a specific part of the given study case of offshore power transmission system in the North Sea, and the impacts associated to the II solutions are evaluated quantitatively in terms of economic indicators, namely CAPEX, OPEX, and TOTEX. Furthermore, the performance of each solution against various disturbances are demonstrated by EMT simulations.