Research on DFIG-VSG Power Decoupling Control Strategy Based on Virtual Current Feed-Forward Compensation

Introduction: Wind power generation systems using a Doubly-Fed Induction Generator (DFIG) with Virtual Synchronous Generator (VSG) technology experience power coupling issues during grid connection operation, which are particularly severe under conditions of high impedance ratios in power transmission lines and large power angles. Therefore, it is necessary to explore effective methods to weaken the power coupling effect in the DFIG-VSG grid-connected system in order to improve its stability. Method: A DFIG-VSG power decoupling control strategy based on virtual current feed-forward compensation is proposed. The power coupling mechanism of the grid-connected system is thoroughly analyzed. Building on virtual impedance decoupling technology, virtual current is introduced to perform real-time power compensation on the VSG power loop, dynamically eliminating the coupling effects between power loops. Results: Compared with the traditional virtual impedance decoupling strategy, the proposed virtual current decoupling strategy can effectively reduce dynamic maximum deviation in active and reactive power, shorten adjustment time, and eliminate steady-state deviation under Pref step, Qref step, and power grid frequency disturbance simulation conditions, with more significant decoupling effects. Discussion: The simulation results in this paper confirm the effectiveness and feasibility of the virtual current decoupling strategy in reducing system dynamic deviation and shortening adjustment time, providing reliable technical support for improving grid stability. However, practical application requires addressing issues such as hardware and algorithm optimization. Conclusion: The DFIG-VSG power decoupling control strategy based on virtual current feed-forward compensation effectively achieves power decoupling and significantly improves the system’s dynamic response performance and stability.