Frequency Support from Wind Farms Utilizing MTDC Grids

This paper proposes a novel optimal control strategy applied to the multi-terminal direct current (MTDC) systems connecting wind farms (WFs) and AC areas. In this strategy, the distribution ratio, according to which the wind power is shared among the AC areas, is kept at an optimal value. Through this measure, the WFs could provide frequency support to the AC areas. The simulation results show that the frequency deviations in interconnected AC areas are kept within a limit level under the control of this strategy. Additionally, in this strategy, all individual wind turbine generators (WTGs) could operate in the maximum power point tracking (MPPT) mode to make the full use of wind resource.