Generator utilizing fluid-induced oscillations

• US 7,821,144 B2
• Filed: 07/20/2009
• Issued: 10/26/2010
• Est. Priority Date: 12/01/2006
• Status: Expired due to Fees

• Current Assignee: Humdinger Wind Energy LLC
• Original Assignee: Humdinger Wind Energy LLC
• Inventors: Frayne, Shawn M.
• Primary Examiner(s): Patel; T C
• Assistant Examiner(s): Mohandesi; Iraj A
• Application Number:
  US12/506,099
• Publication Number:
  US 20090309362A1
• Time in Patent Office: 463 Days
• Field of Search: 290/1.R, 290/40.C, 605/13
• US Class Current: 290/1.00R
• CPC Class Codes: F03B 17/06 using liquid flow with predominantly kinetic energy conversion, e.g. of swinging-flap type , "run-of-river", "ultra-low head" F03B13/264 takes precedence
• CPC Class Codes: F03D 5/00 Other wind motors controlling thereof F03D7/00
• CPC Class Codes: H02K 35/04 with moving coil systems and stationary magnets
• CPC Class Codes: H02K 7/1876 with reciprocating, linearly oscillating or vibrating parts
• CPC Class Codes: Y02B 10/30 Wind power
• CPC Class Codes: Y02B 10/70 Hybrid systems, e.g. uninterruptible or back-up power supplies integrating renewable energies
• CPC Class Codes: Y02E 10/20 Hydro energy
• CPC Class Codes: Y02E 10/30 Energy from the sea, e.g. using wave energy or salinity gradient
• CPC Class Codes: Y02E 10/70 Wind energy
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

An electrical generator including a magnetic field generator and at least one energy converter for converting energy present in fluid flows into vibrations or oscillations. The converter includes a flexible membrane having at least two fixed ends. The membrane vibrates when subject to a fluid flow. One of the electrical conductor and the magnetic field generator is attached to the membrane and configured to move with the membrane. The vibration of the membrane caused by the fluid flow causes a relative movement between the electrical conductor and the applied magnetic field. The relative movement causes a change in the strength of the magnetic field applied to the electrical conductor, and the change in the strength of the magnetic field applied to the electrical conductor induces a current flowing in the conductor.

Claims

1. A method for modifying the performance of an electrical generator in response to environmental conditions comprising the steps of:

providing a flexible membrane having at least two fixed ends;

allowing the membrane to vibrate when subject to a fluid flow;

providing an electrical conductor, providing a magnetic field generator that applies a magnetic field to the electrical conductor, and attaching one of the electrical conductor and the magnetic field generator to the membrane;

detecting the speed of the fluid flow;

adjusting the membrane based upon the detected speed of the fluid flow.

2. The method of claim 1, wherein the step of detecting the speed of the fluid flow includes the step of detecting and comparing the voltage generated by the electrical generator.

3. The method of claim 1, wherein the step of adjusting the membrane includes adjusting the tensioning of the membrane.

4. The method of claim 3, wherein the step of adjusting the tensioning of the membrane includes the step of adjusting the tension of the membrane if the detected speed of the fluid flow is greater than a predetermined value.

5. The method of claim 4, wherein the step of adjusting tensioning of the membrane includes reducing the tension of the membrane.

6. The method of claim 3, wherein the step of adjusting tensioning of the membrane includes maintaining a predetermined tension in the membrane.

7. The method of claim 6, wherein the step of adjusting tensioning of the membrane includes the steps of providing a constant force mechanism, coupling the constant force mechanism to the two fixed ends of the membrane, and allowing the constant force mechanism to maintain a predetermined tension in the membrane.

8. The method of claim 7, wherein the step of providing a constant force mechanism includes the step of providing a constant force spring.

9. The method of claim 1, wherein the step of adjusting the membrane includes twisting the membrane.

10. The method of claim 9, wherein the step of twisting the membrane includes twisting the entire membrane.

11. The method of claim 9, wherein the step of twisting the membrane includes twisting the membrane if the detected speed of the fluid flow is greater than a predetermined value.

12. An electrical generator and fluid flow detector comprising:

a flexible membrane having at least two fixed ends, wherein the membrane vibrates when subject to a fluid flow;

an electrical conductor and a magnetic field generator that applies a magnetic field to the electrical conductor, wherein one of the electrical conductor and the magnetic field generator is attached to the membrane and configured to move with the membrane;

wherein the vibration of the membrane caused by the fluid flow causes a relative movement between the electrical conductor and the applied magnetic field;

whereby the relative movement causes a change in the strength of the magnetic field applied to the electrical conductor; and

the change in the strength of the magnetic field applied to the electrical conductor induces a current flowing in the conductor; and

wherein the current is detected to indicate the presence of a fluid flow.

13. The generator of claim 12, further comprising a second magnetic field generator that is used to stimulate oscillation.

14. The generator of claim 13, further comprising a linear generator that includes a magnet, wherein the second magnetic field generator is used to stimulate oscillation of the magnet of the linear generator.

15. The generator of claim 13, wherein the second magnetic field generator is incorporated into the membrane.

16. The generator of claim 13, wherein the second magnetic field generator is used to stimulate oscillation without contact by providing a force selected from the group consisting of repulsion and attraction.

17. The generator of claim 12, further comprising a linear generator coupled to the membrane.

18. The generator of claim 12, further comprising a low profile mass provided on the membrane that reduces torsion of the vibration of the membrane.

19. The generator of claim 18, wherein the low profile mass is of a symmetric shape.

20. The generator of claim 12, wherein the electrical conductor includes a set of coil that is filled with a flux enhancer selected from the group consisting of ferrite powder and a laminated ferrous metal.

21. The generator of claim 12, wherein the magnetic field generator includes magnetic core that is surrounded with a field enhancer selected from the group consisting of laminated ferromagnetic material, powdered ferromagnetic material, and ferromagnetic material.

22. The generator of claim 12, wherein the magnetic field generator is an electromagnet.

23. The generator of claim 22, wherein the electromagnet includes a ferromagnetic core surrounded by a conductor.

24. The generator of claim 23, wherein the conductor is a coil.

25. The generator of claim 12, wherein the magnetic field generator is composed of a material selected from the group consisting of:

NdFeB rare earth magnet, ceramic magnet, Alnico magnet, and Samarium-cobalt magnet.

26. The generator of claim 12, wherein the flexible membrane has a substantially elongated shape.

27. The generator of claim 26, wherein the flexible membrane has a shape selected from the group consisting of:

tapered, flat, and airfoil-like.

28. An electrical generator and fluid flow detector comprising:

a flexible membrane having at least two fixed ends, wherein the membrane vibrates when subject to a fluid flow;

a supporting structure, wherein the fixed ends of the membrane are affixed to the supporting structure,

an electrical conductor and a magnetic field generator that applies a magnetic field to the electrical conductor, wherein the magnetic field generator is attached to the membrane and the electrical conductor is positioned on the supporting structure;

wherein the vibration of the membrane caused by the fluid flow causes a relative movement between the electrical conductor and the applied magnetic field;

whereby the relative movement causes a change in the strength of the magnetic field applied to the electrical conductor; and

the change in the strength of the magnetic field applied to the electrical conductor induces a current flowing in the conductor.

29. The generator of claim 28, further comprising at least one additional flexible membrane that includes at least two ends fixed to the supporting structure and an attached magnetic field generator that applies a magnetic field applied to an electrical conductor, wherein

the at least one additional flexible membrane vibrates when subject to a fluid flow;

and

the vibration of the at least one additional flexible membrane caused by the fluid flow causes a relative movement between the magnetic field generator attached to the additional flexible membrane and the electrical conductor;

whereby the relative movement causes a change in the strength of the magnetic field applied to the electrical conductor attached to the at least one additional membrane; and

the change in the strength of the magnetic field applied to the electrical conductor attached to the at least one additional membrane induces a current flowing in the conductor.

30. The generator of claim 29, further comprising an additional electrical conductor.

31. The generator of claim 29, wherein the current induced by the relative movement of the magnetic field generator on the flexible membrane is out of phase from the current induced by the relative movement of the magnetic field generator on the at least one additional flexible membrane.

32. The generator of claim 29, further comprising a second support structure, and wherein the at least two fixed ends of the at least one additional flexible membrane are fixed to the second support structure.

33. The generator of claim 32, wherein the support structure and the second support structure have a predetermined relative spatial relationship.

34. The generator of claim 33, further comprising frame work that determines the relative spatial relationship between the support structure and the second support structure.

35. An electrical generator and fluid flow detector comprising:

a flexible membrane having a fixed end, wherein the membrane vibrates when subject to a fluid flow;

an electrical conductor;

a magnetic field generator attached to the membrane, wherein the magnetic field generator applies a magnetic field to the electrical conductor;

wherein the vibration of the membrane caused by the fluid flow causes a relative movement between the electrical conductor and the applied magnetic field;

whereby the relative movement causes a change in the strength of the magnetic field applied to the electrical conductor; and

the change in the strength of the magnetic field applied to the electrical conductor induces a current flowing in the conductor.

36. The generator of claim 35, wherein the flexible membrane has two fixed ends.

37. The generator of claim 36, wherein the magnetic field generator is positioned at a location on the membrane substantially closer to a fixed end than to the middle of the membrane in between the two fixed ends of the membrane.

38. The generator of claim 35, wherein the magnetic field generator is positioned underneath the flexible membrane.

39. The generator of claim 35, further comprising a second magnetic field generator attached to the membrane.

40. The generator of claim 35, further comprising a second electrical conductor.

41. The generator of claim 35, further comprising a supporting structure, and wherein the electrical conductor is positioned on the supporting structure.

42. The generator of claim 35, wherein the electrical conductor is positioned adjacent to the magnetic field generator, and wherein the vibration of the membrane caused by the fluid flow causes the magnetic field generator to move substantially along a plane adjacent but not intersecting with the electrical conductor.

43. The generator of claim 42, further comprising a second electrical conductor positioned substantially opposite of the electrical conductor, and wherein the vibration of the membrane caused by the fluid flow causes the magnetic field generator to move substantially along a plane adjacent but not intersecting with both the electrical conductor and the second electrical conductor.

44. The generator of claim 43, wherein the electrical conductor and the second electrical conductor are positioned on opposite sides of the magnetic field generator.

45. A method for generating electricity from fluid flow comprising the steps of:

providing a housing;

providing a stationary element contained within the housing;

providing a moving element contained within the housing;

allowing the moving element to move within a range of motion relative to the stationary element when subject to a fluid flow;

wherein there is no physical grinding between the moving element with both the housing and the stationary element within the range of motion;

wherein the relative movement between the stationary element and the moving element generates electricity.