Patent ID: 9556850
Date: 2017-01-31
CPC Classifications: F03D,F05B,Y02E

Claim:
1. A method of controlling a wind turbine rotor blade, the blade comprising a pitch axis about which the blade can be pitched, and a flap movable to alter the aerodynamic profile of the blade, the method comprising: providing a pitch angle request (θ) to a pitch actuator, wherein the pitch angle request (θ) is converted to a first parameter (ΔCL_θ) that represents a change in lift force at the location of the flap as a result of the rotor blade being pitched according to the pitch angle request (θ); determining an initial flap angle request (β_flap); providing a decoupled flap angle request (β) to a flap actuator; wherein the decoupled flap angle request (β) is calculated from the pitch angle request (θ) and the initial flap angle request (β_flap) such that the decoupled flap angle request (β) provided to the flap actuator does not counteract the pitch angle request (θ); determining a second parameter (β_θ), wherein the second parameter (β_θ) represents the flap angle of the flap if the rotor blade is not pitched (θ=0), that will provide a change in lift force at the location of the flap that is equivalent to the change in lift force (ΔCL_θ) as a result of the rotor blade being pitched according to the pitch angle request (θ); and pitching the blade according to the pitch angle request (θ) and moving the flap according to the decoupled flap angle request (β).