SHUTDOWN CONTROLLER FOR A WIND TURBINE AND A METHOD OF SHUTTING DOWN A WIND TURBINE

• US 20140334927A1
• Filed: 11/21/2012
• Published: 11/13/2014
• Est. Priority Date: 11/21/2011
• Status: Active Grant

• Current Assignee: Vestas Wind Systems A/S
• Original Assignee: Vestas Wind Systems A/S
• Inventors: Hammerum, Keld
• Granted Patent: US 9,810,199 B2
• Time in Patent Office: Days
• US Class Current: 416/1
• CPC Class Codes: F03D 7/0224 Adjusting blade pitch
• CPC Class Codes: F03D 7/0264 for stopping; controlling in emergency situations orientating out of wind F03D7/0208
• CPC Class Codes: F03D 7/042 by means of an electrical or electronic controller
• CPC Class Codes: F03D 7/045 with model-based controls
• CPC Class Codes: F05B 2270/327 Rotor or generator speeds
• CPC Class Codes: F05B 2270/328 Blade pitch angle
• CPC Class Codes: F05B 2270/331 Mechanical loads
• CPC Class Codes: F05B 2270/332 Maximum loads or fatigue criteria
• CPC Class Codes: F05B 2270/334 Vibration measurements
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

The invention provides a shutdown controller for a wind turbine. To improve the estimation of a state of the wind turbine, the controller comprises at least two sensors being adapted to provide sensor data significant for different mechanical states in the wind turbine. The controller can provide an estimated state of the wind turbine based on the sensor data from the at least two sensors and compare the state of the wind turbine with a predefined detection limit to provide a shutdown signal if the estimated state is outside the detection limit.

Claims

1. A shutdown controller for a wind turbine, the controller comprising at least two sensors being adapted to provide sensor data significant for different mechanical states in the wind turbine, the controller being adapted to provide an estimated state of the wind turbine based on the sensor data from the at least two sensors, wherein the controller is adapted to compare the state of the wind turbine with a predefined detection limit, and to provide a shutdown signal if the estimated state is outside the detection limit.

2. A controller according to claim 1, further comprising a communications interface adapted to communicate with a blade pitching device such that shutdown is initiated by blade pitching.

3. A controller according to claim 2, wherein the communications interface is adapted to communicate a pitching speed to the blade pitching device.

4. A controller according to claim 2, wherein the communications interface is adapted to communicate a pitching signal for several blades individually such that shutdown can be initiated by individual blade pitching.

5. A controller according to claim 1, where the estimated state contains at least two quantities selected from the group consisting of rotor speed ω

_R, pitch angle θ

, tower deflection γ

_t, and blade deflection β

.

6. A controller according to claim 1, further comprising selection logic adapted to select between different control schemes each specifying at least one of the detection limit and a shutdown pitching strategy.

7. A controller according to claim 6, wherein the selection logic is adapted to select between the control schemes based on the age of the turbine.

8. A controller according to claim 6, wherein the selection logic is further adapted to select between different control schemes based on experienced loads.

9. A controller according to claim 6, wherein the selection logic is further adapted to count a number of experienced loads above a predefined load limit and to use that number for selecting a suitable control scheme.

10. A controller according to 9claim 6, wherein the selection logic is further adapted to determine a fatigues load history and to select the control scheme there from.

11. A controller according to claim 1, further comprising logic further adapted to adaptively adjust the detection limit based on historical data related to the wind turbine.

12. A controller according to claim 1, wherein the detection limit is expressed as a convex hull.

13. A controller according to claim 12, wherein the controller is adapted to determine whether the state of the wind turbine is within the detection limit by solving a linear program.

14. A controller according to claim 13, where solving of the linear program includes the use of a Simplex-algorithm.

15. A method of shutting down a wind turbine in case of emergency, the method comprising:

providing at least two different sets of data, the sets being significant for different mechanical states in the wind turbine;

providing from the at least two different sets of data, a state of the wind turbine; and

shutting the wind turbine down based on a comparison between the state of the wind turbine and a predefined detection limit.

16. A method according to claim 15, where the detection limit is defined at least partly based on capabilities of a shutdown system of the wind turbine.

17. A method according to claim 15, where the detection limit is defined at least partly based on structural properties of the turbine.

18. A method according to claim 15, further comprising:

determining the detection limit as a convex hull; and

determining if the state of the wind turbine is within the hull by solving a linear program.

19. A method according to claim 18, where solving of the linear program involves the use of a Simplex algorithm.