Counteracting tower oscillations of an idling wind turbine
AssigneeVestas Wind Systems A/S
InventorsFabio Caponetti, Martin Brødsgaard, Thomas Krüger
Life of this patent
Estimating the term…
Abstract
The invention presents a method for operating a horizontal axis wind turbine, the wind turbine comprising a tower and a rotor with at least one rotor blade, the rotor being connected to the tower, and being adapted to drive a generator connected to a utility grid, wherein a pitch angle of each rotor blade is adjustable, the method comprising detecting, when the wind turbine is in an idling power producing situation in relation to the utility grid, a tower oscillation, and controlling, when the wind turbine is in the idling power producing situation, the pitch angle of the at least one rotor blade so as to produce aerodynamic forces counteracting the detected tower oscillation.
Claims20
A method for operating a horizontal axis wind turbine, the wind turbine comprising a tower and a rotor with at least one rotor blade, the rotor being connected to the tower and being adapted to drive a generator connected to a utility grid, wherein a pitch angle of each rotor blade is adjustable, the method comprising:
- detecting, when the wind turbine is in an idling power producing situation in relation to the utility grid, a tower oscillation;
- and
- individually and cyclically controlling, when the wind turbine is in the idling power producing situation, the pitch angle of the at least one rotor blade according to a sinusoidal function so as to produce active damping with aerodynamic forces counteracting the detected tower oscillation, wherein the sinusoidal function is based on time, on an angular position of the at least one rotor blade in a plane of the rotor, and on a rotation frequency of the rotor.
A wind turbine comprising:
- a tower comprising a rotor having a plurality of rotor blades disposed around a hub at unique angular positions, the rotor connected to the tower and adapted to drive a generator connected to a utility grid, wherein a pitch angle of each rotor blade of the plurality of rotor blades is adjustable;
- and
- a controller configured to detect the wind turbine in an idling power producing situation in relation to the utility grid, the controller further configured to detect a tower oscillation,
- wherein the controller is configured to actively counteract the detected tower oscillation by cyclically adjusting the pitch angle of at least one rotor blade of the plurality of rotor blades according to a sinusoidal function based on time, on an angular position of the at least one rotor blade in a plane of the rotor, and on a rotation frequency of the rotor in response to the detected tower oscillation while in the idling power producing situation.
A wind turbine tower controller comprising:
- a speed control unit that generates a static idling pitch reference based on a rotor speed reference and a measured rotor speed, wherein the speed control unit is configured as a feedback controller that determines the static idling pitch reference, based on a difference between a received rotor speed reference and a measured rotor speed;
- a longitudinal damper unit that produces a collective pitch reference offset based on an input from a tower longitudinal acceleration sensor;
- and
- a lateral damper unit that produces a plurality of individual cyclic pitch reference offsets based on an input from a tower lateral acceleration sensor;
- wherein both the static idling pitch reference and the collective pitch reference offset are added to at least one of the plurality of individual cyclic pitch reference offsets based on a sinusoidal function of time, of an angular position of at least one rotor blade in a plane of the rotor, and of a rotation frequency of the rotor to generate an active pitch angle dampening control applied to the at least one rotor blade of the wind turbine while the wind turbine is determined to be in an idling power producing situation in relation to a utility grid.
Dependencies are inferred from the claim text.