US 11,939,959 B2
Stopping a wind turbine rotor based on stored pitch angle signal
Keld Hammerum, Hadsten (DK); and Christian Jeppesen, Aarhus C (DK)
Assigned to VESTAS WIND SYSTEMS A/S, Aarhus N (DK)
Appl. No. 17/779,112
Filed by VESTAS WIND SYSTEMS A/S, Aarhus N. (DK)
PCT Filed Nov. 20, 2020, PCT No. PCT/DK2020/050314
§ 371(c)(1), (2) Date May 23, 2022,
PCT Pub. No. WO2021/098925, PCT Pub. Date May 27, 2021.
Claims priority of application No. PA 2019 70709 (DK), filed on Nov. 21, 2019.
Prior Publication US 2022/0403821 A1, Dec. 22, 2022
Int. Cl. F03D 7/02 (2006.01)
CPC F03D 7/0224 (2013.01) [F03D 7/0264 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for controlling a wind turbine, the wind turbine comprises a rotor with one or more pitch adjustable rotor blades, wherein the method comprises:
storing pitch angles for each of the pitch adjustable rotor blades, the pitch angles being sequentially sampled continuously across at least a fraction of a revolution of the rotor for each rotor blade;
generating a stored pitch angle signal for the one or more pitch adjustable rotor blades from the stored pitch angles;
determining at least one periodic component of the stored pitch angle signal;
generating a rotor stop signal to stop the rotor; and
in response to the generating a rotor stop signal, controlling the pitch adjustable rotor blades towards a feathering position using a pitch control signal containing the at least one periodic component.