Wind turbine generator, active damping method thereof, and windmill tower

• US 8,546,968 B2
• Filed: 02/13/2013
• Issued: 10/01/2013
• Est. Priority Date: 02/27/2004
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Wakasa, Tsuyoshi, Ide, Kazunari, Hayashi, Yoshiyuki, Shibata, Masaaki
• Primary Examiner(s): Cuevas, Pedro J
• Application Number:
  US13/766,061
• Publication Number:
  US 20130230396A1
• Time in Patent Office: 230 Days
• Field of Search: 290/44, 290/55
• US Class Current: 290/44
• CPC Class Codes: F03D 7/0224 Adjusting blade pitch
• CPC Class Codes: F03D 7/0296 to prevent, counteract or reduce noise emissions
• CPC Class Codes: F03D 7/043 characterised by the type of control logic
• CPC Class Codes: F03D 9/25 the apparatus being an electrical generator F03D9/22 takes precedence
• CPC Class Codes: F05B 2260/71 as a function of flow velocity
• CPC Class Codes: F05B 2260/74 by turning around an axis perpendicular the rotor centre line
• CPC Class Codes: F05B 2260/821 Parameter estimation or prediction
• CPC Class Codes: F05B 2260/96 Preventing, counteracting or reducing vibration or noise
• CPC Class Codes: F05B 2270/1021 by keeping it below damagingly high values
• CPC Class Codes: F05B 2270/309 Rate of change of parameters
• CPC Class Codes: F05B 2270/334 Vibration measurements
• CPC Class Codes: F05B 2270/404 active, predictive, or anticipative
• CPC Class Codes: F05B 2270/807 Accelerometers
• CPC Class Codes: Y02B 10/30 Wind power
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

A wind turbine generator, an active damping method thereof, and a windmill tower in which vibrations of the wind turbine generator itself or the windmill tower can be reduced at low cost are provided. The acceleration is detected with an accelerometer attached to the nacelle. In an active damping unit, a pitch angle of windmill blades for generating a thrust is calculated on the basis of the acceleration, and the pitch angle is output as a blade-pitch-angle command δθ* for damping. In a pitch-angle control unit, a pitch angle of the windmill blades for controlling the output, and the pitch angle is output as a blade-pitch-angle command θ* for output control. The blade-pitch-angle command δθ* for damping is combined with the blade-pitch-angle command θ* for output control using a subtracter. The pitch angle of the windmill blades is controlled on the basis of the resulting blade-pitch-angle command after combining.

Claims

1. A method for reducing the vibration in a wind turbine generator comprising a plurality of blades attached to a hub within a nacelle and a mechanism for active damping of the wind turbine generator including a pitch-angle control mechanism for controlling a pitch angle of the blades on the basis of a blade-pitch-angle command, and an accelerometer, attached to a nacelle, for detecting the acceleration due to vibrations of the nacelle, the method comprising:

(a) applying phase compensation by a predetermined amount,

(b) coupling an integrator to a phase compensator to calculate a speed,

(c) calculating a pitch angle of the blades so as to generate a thrust on the blades which tends to cancel out the vibrations on the nacelle,

(d) providing a blade-pitch-angle command to the pitch angle control mechanism based on the calculated pitch angle and other information, and

(e) coupling a limiter to a device for calculating a pitch angle of the blades for limiting either a blade pitch angle or a rate of variation of the blade pitch angle.

2. The method of claim 1, wherein applying phase compensation comprises a phase lag compensation and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the blade pitch angle.

3. The method of claim 1, wherein applying phase compensation comprises a phase lead compensation and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the blade pitch angle.

4. The method of claim 1, wherein applying phase compensation comprises a phase lag compensation and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the rate of variation of the blade pitch angle.

5. The method of claim 1, wherein applying phase compensation comprises a phase lead compensation and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the rate of variation of the blade pitch angle.

6. The method of claim 1, wherein applying phase compensation corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

<

1, and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the blade pitch angle.

7. The method of claim 6, wherein applying phase compensation is digital.

8. The method of claim 1, wherein applying phase compensation corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

>

1, and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the blade pitch angle.

9. The method of claim 8, wherein applying phase compensation is digital.

10. The method of claim 1, wherein applying phase compensation corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

<

1, and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the rate of variation of the blade pitch angle.

11. The method of claim 10, wherein applying phase compensation is digital.

12. The method of claim 1, wherein applying phase compensation corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

>

1, and wherein coupling a limiter to the device for calculating a pitch angle of the blades limits the rate of variation of the blade pitch angle.

13. The method of claim 12, wherein applying phase compensation is digital.

14. A method for reducing the vibration in a wind turbine generator comprising a plurality of blades attached to a hub within a nacelle and a mechanism for active damping of the wind turbine generator including a pitch-angle control mechanism for controlling a pitch angle of the blades on the basis of a blade-pitch-angle command, and an accelerometer, attached to a nacelle, for detecting the acceleration due to vibrations of the nacelle, the method comprising:

using a phase compensator to apply a phase compensation by a predetermined amount,

coupling an integrator to the phase compensator, wherein using the phase compensation includes at least one of phase lag compensation or phase lead compensation,

using a calculation device to calculate a pitch angle of the blades so as to generate a thrust on the blades which tends to cancel out the vibrations on the nacelle,

coupling a combiner to the calculation device to produce a blade-pitch-angle command value taking into account the pitch angle calculated by the calculation device and other information,

coupling a limiter to the calculation device for limiting either a pitch angle value or the rate of variation of a pitch angle value,

providing the blade-pitch-angle command to the pitch angle control mechanism based on the calculated pitch angle.

15. The method of claim 14, wherein using the phase compensation comprises the phase lag compensation and wherein coupling a limiter to the calculation device limits the pitch angle.

16. The method of claim 14, wherein using the phase compensation comprises the phase lead compensation and wherein coupling a limiter to the calculation device limits the blade pitch angle.

17. The method of claim 14, wherein using the phase compensation comprises the phase lag compensation and wherein coupling a limiter to the calculation device limits the rate of variation of the blade pitch angle.

18. The method of claim 14, wherein using the phase compensation comprises the phase lead compensation and wherein coupling a limiter to the calculation device limits the rate of variation of the blade pitch angle.

19. The method of claim 14, wherein using the phase compensator corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

<

1, and wherein coupling a limiter to the calculation device limits the blade pitch angle.

20. The method of claim 19, wherein the phase compensation is digital.

21. The method of claim 14, wherein using the phase compensator corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

>

1, and wherein coupling a limiter to the calculation device limits the blade pitch angle.

22. The method of claim 21, wherein the phase compensation is digital.

23. The method of claim 14, wherein using the phase compensator corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

<

1, and wherein coupling a limiter to the calculation device limits the rate of variation of the blade pitch angle.

24. The method of claim 23, wherein the phase compensation is digital.

25. The method of claim 14, wherein using the phase compensator corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

>

1, and wherein coupling a limiter to the calculation device limits the rate of variation of the blade pitch angle.

26. The method of claim 25, wherein the phase compensation is digital.