High voltage ride through control strategy of doubly fed induction wind generators based on active resistance

The control strategy of doubly fed induction generator (DFIG) under grid voltage dip has been a focus of discussion up to now. Grid voltage swell will cause more problems for DFIG. In order to study the characteristic and control strategy of high voltage ride through (HVRT) for DFIG, the dynamic behavior during voltage swell is analyzed. It is found that active resistance manages effective to suppress rotor current and torque oscillation, avoid the operation of crowbar circuit, enhance its high voltage ride through technology capability, compared to the conventional control strategy. Simulation and experimental results verify the effectiveness of the control strategy.