Method for controlling air deflectors and pitch angles of wind turbine blades

Patent metadata

Field	Value
Publication number	US-10968888-B2
Application number	US-201716336015-A
Country	US
Kind code	B2
Filing date	Sep 20, 2017
Priority date	Sep 22, 2016
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

A method for controlling a wind turbine is disclosed, the wind turbine comprising a set of wind turbine blades (1), each wind turbine blade (1) being provided with at least one air deflector (2) being movable between an activated position in which it protrudes from a surface of the wind turbine blade (1) and a de-activated position. The occurrence of an event causing a change in operational conditions is registered, and a new operating state for the wind turbine is determined, the new operating state meeting requirements of the changed operational conditions. The air deflectors (2) of the wind turbine blades (1) and pitch angles of the wind turbines blades (1) are controlled in order to reach the new operating state for the wind turbine, and in such a manner that the control of the pitch angles of the wind turbine blades (1) is performed while taking information regarding the control of the air deflectors (2) into account.

First claim

The invention claimed is:

1. A method for controlling a wind turbine, the wind turbine comprising a set of wind turbine blades, each wind turbine blade being provided with at least one air deflector being movable between an activated position in which it protrudes from a surface of the wind turbine blade and a de-activated position, the wind turbine being operated in a first operating state, the method comprising:
registering the occurrence of an event causing a change in operational conditions;
determining a new operating state for the wind turbine, the new operating state meeting requirements of the changed operational conditions; and
controlling the air deflectors of the wind turbine blades and pitch angles of the wind turbines blades in order to reach the new operating state for the wind turbine, wherein the control of the pitch angles of the wind turbine blades is performed while taking information regarding the control of the air deflectors into account, and wherein controlling the air deflectors and the pitch angles of the wind turbine blades comprises:
determining a load impact on the wind turbine and a transition time of reaching the new operating state in a situation where only air deflectors are deployed;
determining that the load impact is larger than a target load impact or that the transition time is larger than a target transition time;
determining a pitch response required to reach the target load impact or the target transition time; and
controlling the pitch angles of the wind turbine blades according to the determined pitch response.

2. The method according to claim 1 , wherein controlling the air deflectors and the pitch angles of the wind turbine blades further comprises:
controlling the air deflectors based on one or more sensor input, using an air deflector controller;
the air deflector controller providing information regarding the control of the air deflectors to a pitch controller; and
controlling the pitch angles of the wind turbine blades, using the pitch controller, and taking the information regarding the control of the air deflectors into account.

3. The method according to claim 1 , wherein controlling the air deflectors and the pitch angles of the wind turbine blades comprises:
determining an air deflector setting, based on the registered event;
controlling the air deflectors in accordance with the determined air deflector setting; and
controlling the pitch angles of the wind turbine blades, while taking the determined air deflector setting into account.

4. The method according to claim 1 , wherein determining an air deflector setting is further based on the first operating state or on the new operating state.

5. The method according to claim 1 , wherein the air deflectors are controlled to be fully activated during the transition from the first operating state to the new operating state, and wherein the pitch angles of the wind turbine blades are controlled to ensure that the target load impact or the target transition time is reached.

6. The method according to claim 1 , wherein the air deflectors and the pitch angles of the wind turbine blades are controlled by means of a central controller.

7. The method according to claim 1 , wherein the air deflectors are controlled by means of an air deflector controller and the pitch angles are controlled by means of a pitch controller, and wherein the air deflector controller and the pitch controller are arranged for communicating with each other.

8. The method according to claim 1 , wherein the registered event is a change in wind direction, a gust, a change in wind shear, a change in power reference, a shut down command, or a grid loss.

9. The method according to claim 1 , wherein each air deflector has at least one pressure sensor associated therewith, each pressure sensor being arranged to measure a pressure prevailing in the vicinity of the associated air deflector, and wherein the air deflectors are at least partly controlled on the basis of measurements performed by the pressure sensors.

10. The method according to claim 9 , wherein the pitch angles of the wind turbine blades are at least partly controlled on the basis of measurements performed by the pressure sensors.

11. A control system for controlling a wind turbine, the wind turbine comprising a set of wind turbine blades, each wind turbine blade being provided with at least one air deflector being movable between an activated position in which it protrudes from a surface of the wind turbine blade and a de-activated position, the wind turbine being operated in a first operating state, the control system, comprising:
a memory containing code; and
a processor which, when executing the code, performs an operation comprising:
registering the occurrence of an event causing a change in operational conditions,
determining a new operating state for the wind turbine, the new operating state meeting requirements of the changed operational conditions, and
controlling the air deflectors of the wind turbine blades and pitch angles of the wind turbines blades in order to reach the new operating state for the wind turbine, wherein the control of the pitch angles of the wind turbine blades is performed while taking information regarding the control of the air deflectors into account, and wherein controlling the air deflectors and the pitch angles of the wind turbine blades comprises:
determining a load impact on the wind turbine and a transition time of reaching the new operating state in a situation where only air deflectors are deployed,
determining that the load impact is larger than a target load impact or that the transition time is larger than a target transition time,
determining a pitch response required in order to reach the target load impact or the target transition time, and
controlling the pitch angles of the wind turbine blades in accordance with the determined pitch response.

12. The control system according to claim 11 , wherein controlling the air deflectors and the pitch angles of the wind turbine blades comprises:
controlling the air deflectors based on one or more sensor input, using an air deflector controller,
the air deflector controller providing information regarding the control of the air deflectors to a pitch controller, and
controlling the pitch angles of the wind turbine blades, using the pitch controller, and taking the information regarding the control of the air deflectors into account.

13. The control system according to claim 11 , wherein controlling the air deflectors and the pitch angles of the wind turbine blades comprises:
determining an air deflector setting, based on the registered event,
controlling the air deflectors in accordance with the determined air deflector setting, and
controlling the pitch angles of the wind turbine blades while taking the determined air deflector setting into account.

14. The control system according to claim 13 , wherein determining an air deflector setting is further based on the first operating state or on the new operating state.

15. A wind turbine, comprising:
a tower;
a nacelle disposed on the tower;
a rotor extending from the nacelle;
a set of wind turbine blades disposed on one end of the rotor, each wind turbine blade being provided with at least one air deflector being movable between an activated position in which it protrudes from a surface of the wind turbine blade and a de-activated position, the wind turbine being operated in a first operating state; and

a control system operable to perform an operation, comprising:
registering the occurrence of an event causing a

Assignees

• Vestas Wind Sys As

Inventors

• Christensen Poul Brandt
• Thybo Claus
• Thomsen Jesper Sandberg

Classifications

• F03D17/00

  Monitoring or testing of wind motors, e.g. diagnostics (testing during commissioning of wind motors F03D13/30) · CPC title

• F05B2260/71

  as a function of flow velocity · CPC title

• F05B2240/3052

  adjustable · CPC title

• F05B2240/221

  with horizontal axis · CPC title

• F05B2270/20

  to optimise the performance of a machine · CPC title