Fault Ride-Through Control Strategy of Doubly-Fed Wind Turbine Under Symmetrical Grid Faults

For doubly-fed induction genera tors (DFIG), large induced electromotive force will be generated in the rotor circuit during grid failure. Without proper protection measures, the rotor circuit of the doubly-fed motor will generate a large inrush current and even damage the rotor-side converter (RSC). Aiming at this problem, this paper proposes a low-voltage ride-through (LVRT) control strategy for voltage source doubly-fed wind turbines based on transient compensation. First, the transient model of the stator flux linkage of the motor is analyzed, and the transient compensation is injected into the rotor side in a timely manner. Then, the phase angle of the compensation is optimized through vector analysis, which minimizes the rotor current impact at the moment of failure and enhances the stable operation of the doubly-fed wind generator under grid failure. Finally, this paper verifies the correctness of the proposed strategy through corresponding simulations.