Dynamic Impedance Control of Low Voltage Ride through of Doubly-Fed Induction Generator

Aiming at the low-voltage ride-through problem of double-fed induction generator (DFIG), a DFIG dynamic impedance control method based on the principle of demagnetization is proposed. This method uses the fuzzy controller to realize the real-time control of impedance, and dynamically adjusts the impedance value of the virtual impedance through the judgment of the rotor current and voltage, so as to achieve the purpose of reducing the current and voltage on the rotor side, reducing the system oscillation time, ensuring that the DFIG system is not delisted from the power grid, and protecting the purpose of the DFIG system. This method does not need to rely on the system model, which enhances the adaptability and robustness of the system. This paper describes the hazard of power grid voltage dip, theoretically analyzes the characteristics of DFIG, gives the implementation method of dynamic impedance, and finally realizes the feasibility of the method.