Patent ID: 8232662

Claim:
A start-up method of a wind turbine generator, comprising: a step of increasing a pitch angle of a wind turbine blade from a feather pitch angle to a fine pitch angle, wherein the step of increasing said pitch angle includes using a controller to: determine, based on first to n th pitch angles (n≧2) greater than said feather pitch angle and smaller than said fine pitch angle and first to n th rotational speed conditions associated with said first to n th pitch angles, respectively, whether a control target rotational speed, which is a wind turbine speed or generator speed, satisfies an i th rotational speed condition out of said first to n th rotational speed conditions when said pitch angle reaches an i th rotational speed out of said first to n th pitch angles, the first to n th pitch angles and the first to nth n-th rotational speed conditions being stored in a storage unit of the controller, wherein n≧i≧1; decrease said pitch angle to an (i−1) th pitch angle or said feather pitch angle in a case that said control target rotational speed does not satisfy said i th rotational speed condition when said pitch angle reaches the ith i-th pitch angle; and increase said pitch angle to an (i+1) th pitch angle or said fine pitch angle in a case that said control target rotational speed satisfies said i th rotational speed condition when said pitch angle reaches said i th pitch angle.