Optimal Power Flow Control of VSC-Based Multiterminal DC Network for Offshore Wind Integration in the North Sea

Europe is rapidly expanding its wind energy capacity, especially offshore. Hence, the construction of a multiterminal dc (MTdc) network could bring several advantages to accommodate the generated electrical energy, but will also bring many challenges. This paper focuses on one of these challenges, namely the operation and control of an MTdc network. Moreover, a study is carried on how to optimally operate and control an offshore MTdc network for integration of wind energy in the North Sea. An evolutionary strategy called covariance matrix adaptation (CMA) is employed to obtain optimal power flows inside the offshore network. The MTdc grid is composed of 19 nodes, interconnecting nine offshore wind farms to five European countries. The optimal power flow results obtained from the CMA algorithm are tested in a dynamic simulation model to check the control strategy performance in different case studies.