Optimal power output control of fractional frequency wind-power generation system

The control strategy to optimize the power output is introduced for the fractional frequency wind power generation system in VSVF(Variable-Speed Variable-Frequency) operation without wind velocity measuring. Field orientation control technology is used to control the electromagnetic torque of induction generator for regulating the wind turbine rotor speed and controlling the power utilization coefficient. With the consideration of wake effects, the VSVF wind power generation system model is developed with PSCAD/EMTDC, based on which, two types of control strategy, the optimal power output and the optimal wind power capture, are analyzed and compared. Simulative results demonstrate that, under wind speed fluctuation, the optimal power output control strategy can effectively reduce the mechanical stress and output power fluctuation.