Voltage recovery of grid-connected wind turbines with DFIG after a short-circuit fault

The fast development of wind power generation brings new requirements for wind turbine integration to the network. After the clearance of an external short-circuit fault, the voltage at the wind turbine terminal should be reestablished with minimized power losses. This paper concentrates on voltage recovery of variable speed wind turbines with doubly fed induction generators (DFIG). A simulation model of a MW-level variable speed wind turbine with a DFIG developed in PSCAD/EMTDC is presented, and the control and protection schemes are described. A new control strategy is proposed to reestablish the wind turbine terminal voltage after the clearance of an external short-circuit fault, and then restore the normal operation of the variable speed wind turbine with DFIG, which has been demonstrated by simulation results.