A control method of the low voltage ride through in the doubly-fed induction generator wind turbine

Due to the drawbacks that the Crowbar-based doubly-fed induction generator (DFIG) wind turbine needs to absorb reactive power during grid voltage sag, a new kind of low voltage ride-through (LVRT) control strategy of DFIG wind turbines is designed with a resistance series directly in rotor protect topology. Then, the transient process of the new power turbine during the voltage sag is analyzed based on MATLAB/Simulink simulation. The results show that the proposed topology can suppress the over-high transient current in the rotor during grid voltage sag, and an additional feature of the topology is that reactive power can be supplied to the grid during grid voltage sag in order to facilitate voltage restoration.