Torsional Vibrations Suppression for GFM-DFIG Wind Turbine Considering Electromechanical Interaction Effects

To effectively enhance the voltage and frequency supporting capabilities for power grid, the doubly fed induction generator based wind turbine (DFIG WT) can be connected to the grid via grid-forming (GFM) control. However, the GFM control intensifies the dynamic interaction between the mechanical and electrical system of DFIG WT, which exacerbates the risk of torsional vibrations (TVs). This paper explains the underlying mechanism of TVs for GFM-DFIG WT through the active power loop (APL) model. Furthermore, the torque analysis is utilized to reveal the dominant factor of different control parameters on drivetrain damping. Results demonstrate that parameter adjustment alone cannot guarantee stability under ultra-weak grid. For the sake of addressing this issue, the damping controller implementation optimization is conducted to maximize drivetrain damping of GFM-DFIG WT. Finally, the accuracy of the aforementioned conclusions is substantiated by experiment.