Patent ID: 9739264
Date: 2017-08-22
CPC Classifications: F03D,F05B,Y02E

Claim:
1. A method of operating a wind turbine in response to a wind speed greater than nominal wind speed, the wind turbine having at least a rotor with a plurality of blades and a generator comprising a generator rotor and a generator stator, the method comprising at wind speeds above a first wind speed, increasing a pitch angle of the blades so as to reduce a rotor speed with increasing wind speed, the first wind speed being greater to a nominal wind speed, wherein at a second wind speed, a speed of the generator rotor is equal to a synchronous generator rotor speed, the second wind speed being greater to the first wind speed, and wherein at wind speeds greater to the second wind speed, the speed of the generator rotor is lower than the synchronous generator rotor speed, and as wind speed increases beyond the first wind speed and at least to an intermediate wind speed less than the second wind speed, maintaining generator torque constant at a value of the generator torque at nominal wind speed value while reducing the speed of the generator rotor.