Model predictive control of multi-terminal DC grids with offshore wind farms

This paper proposes a control structure based on the model predictive control (MPC) for control of multi-terminal DC (MTDC) grids with offshore wind generation. In the proposed strategy, an outer loop is designed to generate reference currents for the inner loop in alpha-beta reference frame. Then, in the inner loop, a model predictive controller is designed to follow the reference currents generated by the outer loop. The MPC provides a good transient performance for voltage source converters (VSCs) in the MTDC grids. Moreover, for the grid-side converters, a voltage droop control strategy is considered as well. Simulation results confirm stable operation of the proposed control strategy in case of variation in wind generation and changes in the AC grids demand.