US 12,460,618 B2
Wind turbine yawing system with multiple mechanical braking levels
Niels Henrik Pedersen, Aarhus (DK); Jens-Kristian Egsgaard Langkjær, Aarhus (DK); Julio Xavier Vianna Neto, Skødstrup (DK); Søren Dalsgaard, Hadsten (DK); and Jesper Lykkegaard Neubauer, Hornslet (DK)
Assigned to VESTAS WIND SYSTEMS A/S, Aarhus N (DK)
Appl. No. 18/723,546
Filed by VESTAS WIND SYSTEMS A/S, Aarhus N (DK)
PCT Filed Dec. 22, 2022, PCT No. PCT/DK2022/050307
§ 371(c)(1), (2) Date Jun. 24, 2024,
PCT Pub. No. WO2023/117025, PCT Pub. Date Jun. 29, 2023.
Claims priority of application No. PA202170664 (DK), filed on Dec. 23, 2021.
Prior Publication US 2025/0059948 A1, Feb. 20, 2025
Int. Cl. F03D 7/02 (2006.01)
CPC F03D 7/0204 (2013.01) [F03D 7/0248 (2013.01); F05B 2260/902 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A system for controlling a wind turbine that includes a tower and a nacelle, the system comprising:
a yaw drive configured to selectively apply torque between the tower and the nacelle;
a plurality of mechanical brakes that, when each of the mechanical brakes is in a closed state, provides a first amount of braking torque between the tower and the nacelle;
one or more processors operatively coupled to the yaw drive and the plurality of mechanical brakes; and
a memory coupled to the one or more processors and including program code that, when executed by the one or more processors, causes the system, under operational conditions, to:
while in a yawing state, activate the yaw drive to rotate the nacelle to a first orientation relative to the tower;
in response to the nacelle reaching the first orientation, transition from the yawing state to a parked by brake state in which the yaw drive is inactive, each mechanical brake of a first subset of the plurality of mechanical brakes is in an open state, and each mechanical brake of a second subset of the plurality of mechanical brakes is in the closed state, wherein the second subset of the plurality mechanical brakes provides a second amount of braking torque between the tower and the nacelle that is less than the first amount of braking torque;
in response to detecting a rotation of the nacelle while in the parked by brake state, transition from the parked by brake state to a parked by motor state in which the yaw drive is activated to provide a counter acting torque in opposition to the detected rotation of the nacelle;
cause transition between the parked by brake state and the parked by motor state during a period of time, wherein transition from the parked by motor state to the parked by brake state occurs each instance an amount of the counter acting torque being provided in opposition to the detected rotation of the nacelle while in the parked by motor state drops below a first torque threshold that is below the second amount of braking torque; and
change the first torque threshold or a number of mechanical brakes in the second subset of the plurality of mechanical brakes, or both, based on the number of times the system has transitioned between the parked by brake state and the parked by motor state during the period of time.