Grid-connected control based on dual compensation-droop for direct-drive PMSG wind power systems

In order to realize the safe and stable grid-connection of the direct-drive permanent magnet synchronous generator (D-PMSG) used in wind power generation systems, a gird-connected control strategy combined dual-compensation droop and multiple quasi proportional resonance (MQPR) is proposed in this paper. Based on the traditional droop control, a DC voltage compensation is introduced in the voltage control, which can quickly adjust the fluctuation of DC bus voltage. A capacitor current compensation is joined in the current control, which can effectively reduce the impact of current error caused by the filtering capacitor. Meanwhile, a MQPR controller is designed to replace the PI controller for filtering out multiple harmonic currents in the system. The effectiveness of the proposed control strategy is verified by establishing a simulation model and comparing it with the dual closed-loop PI and traditional droop control strategies.