Dynamic response of Doubly Fed Induction Generator during voltage drops

This paper proposed the drawback of Doubly Fed Induction Generator (DFIG) during voltage drops. Since the stator winding of DFIG is directly connected to the grid, DFIG is sensitive to the grid fault, especially to voltage drops. With the increasing capacity of wind turbines, the wind turbines need to meet the certain ability to across low voltage. The research of dynamic behavior based on DFIG during voltage drops is important to provide the evidence to protecting circuit. Due to the electromagnetic transient process of DFIG, this paper analyzed the analytical expressions of stator current? rotor current and the dc bus voltage both in symmetrical short-circuit and asymmetric short-circuit. The simulation results in PSCAD/EMTDC proved the correctness of the theoretical expression.