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

• US 8,299,643 B2
• Filed: 08/29/2011
• Issued: 10/30/2012
• Est. Priority Date: 02/27/2004
• Status: Active Grant

• 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:
  US13/220,121
• Publication Number:
  US 20110309622A1
• Time in Patent Office: 428 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 due to vibrations of a nacelle is detected with an accelerometer attached to the nacelle. In an active damping unit, a pitch angle of windmill blades for generating a thrust on the windmill blades so as to cancel out the vibrations of the nacelle is calculated on the basis of the acceleration, and the pitch angle is output as a blade-pitch-angle command δθ* for damping. On the other hand, in a pitch-angle control unit, a pitch angle of the windmill blades for controlling the output to be a predetermined value is calculated, 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 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, wherein the mechanism comprises:

(a) a phase compensator which applies phase compensation by a predetermined amount,

(b) an integrator coupled to the phase compensator,

(c) a device which, on the basis of the results of the integration and the phase compensation, calculates 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, and

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

2. The generator of claim 1, wherein the phase compensator corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

<

1.

3. The generator of claim 1, wherein the phase compensator corresponds to a transfer function (1+sα

T1)/(1+sT1) wherein α

>

1.

4. The generator of claim 1, further comprising a device for calculating the blade-pitch-angle command provided by the device (d) taking into account the pitch angle calculated by the device (c) and other information.

5. The generator of claim 1, further comprising a limiter coupled to the device (c) for limiting a blade pitch angle.

6. The generator of claim 1, further comprising a limiter coupled to the device (c) for limiting a rate of variation of a blade pitch angle.

7. The generator of claim 1, wherein integrator (b) integrates the output of the phase compensator (a).

8. The generator of claim 4, wherein the other information comprises a pitch angle of the windmill blades for controlling the wind turbine generator calculated on the basis of wind speed, the rotational speed of a windmill rotor, or an output of the wind turbine generator.

9. The generator of claim 8, wherein the other information comprises the output in kW generated by the wind turbine generator.

10. 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, wherein the mechanism comprises:

a phase compensator which applies phase compensation by a predetermined amount, an integrator coupled to the phase compensator,

a calculation device which, on the basis of the results of the integration and the phase compensation, calculates a pitch angle of the windmill blades so as to generate a thrust on the windmill blades which tends to cancel out the vibrations on the nacelle, a combiner coupled to the calculation device which produces a blade-pitch-angle command value taking into account the pitch angle calculated by the calculation device and other information,

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

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