Comparison of resonant current regulators for DFIG during grid voltage distortion

We investigate two different kinds of resonant current regulators for a doubly fed induction generator （DFIG） under distorted grid voltage conditions： proportional integral resonant （PIR） regulator with traditional resonant part and vector propor- tional integral （VPI） regulator with VPI resonant part. Based on the mathematical model of DFIG under distorted grid voltage, the transfer function and frequency response characteristics of the two current regulators are analyzed and compared. The superiority of the VPI current regulator over the PIR regulator is pointed out, and the influence of discretization methods on the performance of the resonant current regulator is studied. All the results are validated by MATLAB simulation and experiments.