Study on the Low Voltage Ride through Technology of Double-fed Wind Power Generation

A novel rotor-side protection circuit is introduced in view of the problem of low voltage ride through in double-fed variable speed constant frequency wind power generation system. The motor´s mathematical model of steady and transient states have been established, and meanwhile the dynamic response of the double-fed induction generator during the grid voltage drop and after the voltage recovery has been discussed. The simulation results have shown that using the crowbar circuit, designed in this paper, in the rotor-side during the voltage drop can restrain the capacitor voltage increase in DC side effectively and decrease the rotor-side current to protect the rotor-side converter.