Frequency Regulation Strategy for DFIG Combining Over-speed Control and Adaptive Virtual Inertia

The doubly-fed synchronous generator (DFIG) with traditional visual inertia control has fast dynamic response speed but is lacked of refinement control under load fluctuation. In order to improve the dynamic stability of system frequency, a control strategy for DFIG based on over-speed control and adaptive virtual inertia is proposed in this letter. This method simulates the behavior of synchronous generator, constructs the relationship between frequency change rate and virtual inertia, and adaptively changes the inertia of virtual synchronous generator (VSG), thus improving the anti-interference capability of system. Compared with the traditional virtual inertia method, the algorithm has strong robustness. Simulation and experimental results show that the proposed method improves the dynamic stability of system frequency, verifying the feasibility and effectiveness of the proposed control strategy.