Patent ID: 8502404

Claim:
A wind power generation system including a doubly-fed induction generator having a stator connected to a grid, a rotor-side converter connected to a rotor of the doubly-fed induction generator, a turbine connected to the rotor of the doubly-fed induction generator, a grid-side converter connected to the stator of the doubly-fed induction generator and the grid, a controller to connect DC portion of the grid-side converter to DC portion of the rotor-side converter to control the rotor-side converter and the grid-side converter, current detection means for detecting AC input current of the grid-side converter and means for inputting the detected current value to the controller, the controller performing current control using the inputted current detection value, wherein the controller comprises: means for eliminating harmonics component of specified-order from the inputted current detection value of the grid-side converter; means for controlling the grid-side converter using the current detection value in which harmonics are eliminated; and wherein the specified-order is 6nth-order (n being an integer equal to or greater than 1; wherein by supplying p-axis current detection value Ipn to the 6th-order moving average filter, 6th-order harmonics component is removed from output of the 6th-order moving average filter.