MITIGATING WIND TURBINE BLADE NOISE GENERATION

• US 20140142888A1
• Filed: 11/19/2012
• Published: 05/22/2014
• Est. Priority Date: 11/19/2012
• Status: Abandoned Application

• Current Assignee: Elwha LLC (Intellectual Ventures LLC)
• Original Assignee: Elwha LLC (Intellectual Ventures LLC)
• Inventors: Duncan, William David, Hyde, Roderick A., Tuckerman, David B., Wood, Lowell L. Jr.
• Application Number:
  US13/681,196
• Publication Number:
  US 20140142888A1
• Time in Patent Office: Days
• US Class Current: 702/150
• CPC Class Codes: F03D 7/0296 to prevent, counteract or reduce noise emissions
• CPC Class Codes: F05B 2240/30 Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor
• CPC Class Codes: F05B 2260/962 by means creating "anti-noise"
• CPC Class Codes: F05B 2270/333 Noise or sound levels
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

Described embodiments include a wind turbine system. In this embodiment, the system includes a rotor blade attached to a rotor hub drivingly coupled to an electric generator. The system includes a sensor configured to detect a rotational position of the rotor blade relative to a surface of the ground. The system includes a noise controller configured to implement a noise mitigation measure responsive to the detected rotational position of the rotor blade relative to the surface of the ground. In an embodiment, the system further includes a support structure mounted on or in the ground and maintaining the rotor hub a sufficient distance above the surface of the ground to allow the rotor blade to rotate about the rotor hub without contacting the surface of the ground.

Claims

1. A wind turbine system comprising:

a rotor blade attached to a rotor hub drivingly coupled to an electric generator;

a sensor configured to detect a rotational position of the rotor blade relative to a surface of the ground; and

a noise controller configured to implement a noise mitigation measure responsive to the detected rotational position of the rotor blade relative to the surface of the ground.

4. The wind turbine system of claim 1, wherein the sensor is configured to detect a descending motion of a tip of the rotor blade relative to the surface of the ground.

5. The wind turbine system of claim 1, wherein the sensor is configured to detect an ascending motion of a tip of the rotor blade relative to the surface of the ground.

6. The wind turbine system of claim 1, wherein the sensor is configured to detect a motion of a tip of the rotor blade generally parallel to the surface of the ground.

7. The wind turbine system of claim 1, wherein the sensor is configured to detect a rotational position of the rotor blade relative to a portion of the surface of the ground proximate to a structure supporting the rotor hub.

9. The wind turbine system of claim 1, wherein the sensor is configured to detect a rotor blade angle within the generator.

10. The wind turbine system of claim 1, wherein the sensor includes a trigger indexed to the rotor blade.

11. The wind turbine system of claim 1, wherein the sensor includes a microphone.

12. The wind turbine system of claim 1, wherein the sensor includes a pressure sensor.

13. The wind turbine system of claim 1, wherein the sensor includes an optical sensor.

14. The wind turbine system of claim 1, wherein the noise controller is configured to select and implement a noise mitigation measure responsive to the detected rotational position of the rotor blade.

15. The wind turbine system of claim 1, wherein the noise mitigation measure includes changing an orientation of at least a portion of the rotor blade.

16. The wind turbine system of claim 1, wherein the noise mitigation measure includes dynamically shaping airflow over at least a portion of a rotor blade.

17. The wind turbine system of claim 1, wherein the noise mitigation measure includes releasing air from a region on the rotor blade.

18. The wind turbine system of claim 1, wherein the noise mitigation measure includes creating a transpiration airflow on at least a portion of the rotor blade.

19. The wind turbine system of claim 1, wherein the noise mitigation measure is responsive to a detected descending motion of a tip of the rotor blade relative to the surface of the ground.

20. The wind turbine system of claim 1, wherein the noise mitigation measure is responsive to a detected ascending motion of a tip of the rotor blade relative to the surface of the ground.

21. The wind turbine system of claim 1, wherein the noise mitigation measure is responsive to a detected rotational position of the rotor blade relative to the surface of the ground.

22. The wind turbine system of claim 1, wherein the noise mitigation measure varies asymmetrically depending upon a detected rotational position of the rotor blade relative to the surface of the ground.

23. The wind turbine system of claim 1, wherein the noise mitigation measure is implemented by an apparatus carried on at least a portion of the rotor blade.

24. The wind turbine system of claim 23, wherein the rotor blade includes a dynamically shapeable region of the rotor blade located at a first portion of the longitudinal length of the rotor blade, and the noise mitigation measure is implemented by the dynamically shapeable region.

25. The wind turbine system of claim 1, wherein the noise mitigation measure is implemented by a speaker.

26. The wind turbine system of claim 25, wherein the speaker is carried by the rotor blade.

27. The wind turbine system of claim 25, wherein the speaker is carried by a structure supporting the rotor hub.

28. The wind turbine system of claim 25, wherein the speaker is carried by a structure other than a structure supporting the rotor hub.

29. The wind turbine system of claim 1, wherein the system further includes another rotor blade attached to the rotor hub.

32. The wind turbine system of claim 1, wherein the system further includes:

a support structure mounted on or in the ground and maintaining the rotor hub a sufficient distance above the surface of the ground to allow the rotor blade to rotate about the rotor hub without contacting the surface of the ground.

2. (canceled)

3. (canceled)

8. (canceled)

30. (canceled)

31. (canceled)

33. A method comprising:

detecting a position relative to a surface of the ground of a rotating rotor blade of a wind turbine driven electric generator;

authorizing a noise mitigation measure responsive to the detected position of the rotating rotor blade; and

implementing the authorized noise mitigation measure.

34. The method of claim 33, wherein the detecting a position includes detecting a position of a tip of the rotating rotor blade.

35. The method of claim 34, wherein the authorizing includes authorizing a noise mitigation measure responsive to the detected position of the tip of the rotating rotor blade.

36. The method of claim 33, wherein the detecting a position includes detecting a position relative to a surface of the ground closest to a propeller disc described by the rotating rotor blade of a rotating rotor blade of a wind turbine driven electric generator.

39. The method of claim 33, wherein the authorized noise mitigation measure includes dynamically shaping airflow over at least a portion of the rotor blade.

40. The method of claim 33, wherein the authorized noise mitigation measure includes releasing air from a region of the rotor blade.

41. The method of claim 33, wherein the authorized noise mitigation measure includes creating a transpiration airflow on at least a portion of the rotor blade.

42. The method of claim 33, wherein the implementing includes implementing the authorized noise mitigation measure using an apparatus carried on at least a portion of the rotor blade.

43. The method of claim 33, wherein the implementing includes implementing the authorized noise mitigation measure using a speaker.

44. The method of claim 43, wherein the speaker is carried by a structure supporting the rotor hub.

45. The method of claim 43, wherein the speaker is carried by carried by a structure other than a structure supporting the rotor hub.

46. The method of claim 33, wherein the implementing includes implementing the authorized noise mitigation measure using an apparatus not physically coupled with a structure supporting the rotor hub.

37. (canceled)

38. (canceled)

47. A wind turbine system comprising:

a rotor blade attached to a rotor hub drivingly coupled to an electric generator;

a support structure mounted on or in the ground and maintaining the rotor hub a sufficient distance above the surface of the ground to allow the rotor blade to rotate about the rotor hub without contacting the surface of the ground;

a sensor configured to detect a rotational position of the rotor blade relative to the support structure; and

a noise controller configured to implement a noise mitigation measure responsive to the detected rotational position of the rotor blade relative to the support structure.

48. The wind turbine system of claim 47, wherein the sensor is configured to detect a position of a tip of the rotor blade relative to the support structure.

49. The wind turbine system of claim 47, wherein the sensor is configured to detect the rotor blade sweeping past the support structure.

51. The wind turbine system of claim 47, wherein the noise controller is further configured to predict when the rotor blade will sweep past the support structure, and to further implement the noise mitigation measure responsive to the predicted sweep of the rotor blade past the support structure.

52. The wind turbine system of claim 47, wherein the noise mitigation measure is implemented by a controllable feature located on the rotor blade.

53. The wind turbine system of claim 47, wherein the noise mitigation measure is implemented by an apparatus located on the support structure.

54. The wind turbine system of claim 47, wherein the noise mitigation measure is implemented by an apparatus carried by a structure other than a structure supporting the rotor hub.

55. The wind turbine system of claim 47, wherein the noise mitigation measure is responsive to the rotor blade sweeping past the support structure.

56. The wind turbine system of claim 47, wherein the noise mitigation measure is responsive to a detected rotational position of the rotor blade relative to the support structure.

50. (canceled)

57. (canceled)

58. (canceled)

59. A method comprising:

detecting a position relative to a support structure of a rotating rotor blade of a wind turbine driven electric generation system, the support structure mounted on or in the ground and maintaining the rotor hub a sufficient distance above the surface of the ground to allow rotation of the rotor blade about the rotor hub without the rotor blade contacting the ground; and

implementing a noise mitigation measure responsive to the detected position of the rotating rotor blade.

62. The method of claim 59, further comprising:

authorizing the implementing the noise mitigation measure.

66. The method of claim 59, further comprising:

predicting when the rotating rotor blade will pass the support structure.

69. The method of claim 66, wherein the implementing includes implementing a noise mitigation measure responsive to the detected position of the rotating rotor blade and responsive to the predicted passage of the rotating rotor blade past the support structure.

70. The method of claim 59, wherein the implementing includes implementing a noise mitigation measure using an apparatus located on the support structure.

71. The method of claim 59, wherein the implementing includes dynamically shaping airflow over at least a portion of a rotor blade.

73. The method of claim 59, wherein the implementing includes changing an orientation of at least a portion of the rotating rotor blade.

74. The method of claim 59, wherein the implementing includes releasing air from a region of the rotor blade.

75. The method of claim 59, wherein the implementing includes releasing air from a region of the rotor blade as the rotor blade rotates past the support structure.

76. The method of claim 59, wherein the implementing includes creating a transpiration airflow on at least a portion of the rotor blade.

78. The method of claim 59, wherein the implementing includes implementing a noise mitigation measure using an apparatus carried on at least a portion of the rotor blade.

79. The method of claim 59, wherein the implementing includes implementing a noise mitigation measure using an apparatus carried by the support structure.

81. The method of claim 59, wherein the implementing includes implementing a noise mitigation measure using a speaker carried by a structure other than the support structure.

60. (canceled)

61. (canceled)

63. (canceled)

64. (canceled)

65. (canceled)

67. (canceled)

68. (canceled)

72. (canceled)

77. (canceled)

80. (canceled)