Stability Analysis and Enhanced Virtual Synchronous Control for Brushless Doubly-Fed Induction Generator Based Wind Turbines

The brushless doubly fed induction generator (BDFIG) presents significant potential for application in wind power systems, primarily due to its elimination of slip rings and brushes. The application of virtual synchronous control (VSynC), has been demonstrated to effectively augment the inertia of BDFIG systems. However, the dynamic characteristics and stability of BDFIG under weak grid conditions remain largely unexplored. To cope with such issue, this paper methodically investigates the critical stabilizing factors for BDFIG-based wind turbines, and then proposes an enhanced VSynC scheme based on linear active disturbance rejection control (LADRC). The stability analysis reveals that the proposed control strategy can virtually enhance the stability of the grid-tied system in weak grid scenarios. The accuracy of the theoretical analysis and the effectiveness of the proposed method are affirmed through extensive simulations and detailed experiments.