Frequency support from PMSG-based wind turbines with reduced DC-link voltage fluctuations

Frequency droop control is widely used in permanent magnet synchronous generators (PMSGs) based wind turbines (WTs) for grid frequency support. However, under frequency deviations, significant DC-link voltage fluctuations may occur during the transient process due to sudden changes in real power of such WTs. To address this issue, a current feedforward control strategy is proposed for PMSG-based WTs to reduce DC-link voltage fluctuations when the WTs are providing frequency support under grid frequency deviations. Meanwhile, the desired frequency support capability of the PMSG-based WTs can be ensured. Simulation results verify the rationality of the analysis and the effectiveness of the proposed control method.