US 11,885,303 B2
Pitch control of wind turbine blades in a standby mode
Fabio Caponetti, Åbyhøj (DK); and Andre Brandao Martins, Lisbon (PT)
Assigned to VESTAS WIND SYSTEMS A/S, Aarhus N (DK)
Appl. No. 17/793,602
Filed by VESTAS WIND SYSTEMS A/S, Aarhus N. (DK)
PCT Filed Jan. 15, 2021, PCT No. PCT/DK2021/050012
§ 371(c)(1), (2) Date Jul. 18, 2022,
PCT Pub. No. WO2021/143991, PCT Pub. Date Jul. 22, 2021.
Claims priority of application No. PA 2020 70033 (DK), filed on Jan. 16, 2020.
Prior Publication US 2023/0077195 A1, Mar. 9, 2023
Int. Cl. F03D 7/02 (2006.01)
CPC F03D 7/0224 (2013.01) [F05B 2270/327 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method of operating a wind turbine generator comprising a rotor having a plurality of blades, the method comprising:
comparing an indicated rotor speed with a rotor speed target to determine a rotor speed error;
generating a modified rotor speed error by applying a control factor to the rotor speed error;
controlling a pitch angle of each blade via a pitch control system in accordance with the modified speed error;
altering the control factor in dependence on a size of the indicated rotor speed; and
comprising decrementing the control factor when the indicated rotor speed is in a first range of rotor speeds, and wherein decrementing comprises decreasing the control factor by a first decrement when the indicated rotor speed is inside the first range of rotor speeds and is greater than the rotor speed target, and decreasing the control factor by a second decrement when the indicated rotor speed is inside the first range of rotor speeds and is less than the rotor speed target.