Improving Dynamic Performance of DFIG Using Rotor-Side SFCL and DC-Link Brake Chopper During Grid Voltage Swell

To improve the dynamic performance of doubly fed induction generator (DFIG) based wind turbine during grid voltage swell, this paper presents a novel combinational high-voltage ride-through (HVRT) scheme by using a rotor-side superconducting fault current limiter (SFCL) and a DC-link brake chopper. The basic principle, circuit modeling and control strategies of the SFCL and chopper are presented in detail. Then the comparative study between the proposed SFCL-chopper-based combinational scheme and a SFCL-based scheme is conducted. The simulation results obtained show that the stator voltage, rotor current and DC-link voltage behaviors of the DFIG during grid voltage swell are significantly improved.