METHOD AND DEVICE FOR POWER GENERATION

• US 20130076036A1
• Filed: 11/19/2012
• Published: 03/28/2013
• Est. Priority Date: 09/17/2009
• Status: Active Grant

• Current Assignee: The Board of Trustees of Western Michigan University
• Original Assignee: Western Michigan University
• Inventors: Liu, Tianshu
• Granted Patent: US 9,464,623 B2
• Time in Patent Office: Days
• US Class Current: 290/44
• CPC Class Codes: F03D 3/068 mechanically controlled by the rotor structure
• CPC Class Codes: F03D 7/00 Controlling wind motors supplying or distributing electrical power H02J, e.g. arrangements for adjusting, eliminating or compensating reactive power in networks H02J3/18; controlling electric generators H02P, e.g. arrangements for controlling electric generators for the purpose of obtaining a desired output H02P9/00
• CPC Class Codes: Y02E 10/74 Wind turbines with rotation axis perpendicular to the wind direction

Abstract

A fluid flow-powered generator and a method for using the same are described herein. The generator has a rotatable frame, with a first wing and a second wing. The first wing and second wing are pivotally mounted to the frame to allow the angle of attack to be adjusted. A controller is also provided to direct adjustment of the angle of attack of the first wing and the second wing in a coordinated manner while the fluid flow-powered generator is in use. In certain embodiments, the fluid flow-powered generator is operable as an oscillating generator and in other embodiments, the fluid flow-powered generator is operable as a rotating generator. The rotating generator can be arranged along a horizontal axis or a vertical axis. Additionally, certain horizontally oriented generators may be operated as either oscillating generators or rotating generators.

Claims

1. A fluid flow-powered generator, comprising:

a rotatable frame;

a first wing and a second wing, each wing having a leading edge, a trailing edge, a first end and a second end;

each wing having an angle of attack determined by the orientation of a chord line extending through the leading and trailing edges thereof, and each wing pivotally mounted to the frame to allow the angle of attack to be adjusted; and

a controller to direct adjustment of the angle of attack of the first wing and the second wing in a coordinated manner while the fluid flow-powered generator is in use.

2. The fluid flow-powered generator of claim 1, wherein the rotatable frame comprises a central axis member, a first pair of transverse arms and a second pair of transverse arms, each extending from the central axis member and wherein the first wing is mounted at its first end and second end between the first pair of transverse arms and the second wing is mounted at its first end and second end between the second pair of transverse arms.

3. The fluid flow-powered generator of claim 2, wherein the first and second pairs of transverse arms and central axis member are on approximately the same plane, and where the frame is rotatable around the central axis member.

4. The fluid flow-powered generator of claim 3, wherein the frame is mounted on a rotatable table which is adjustable to align the central axis member of the frame perpendicularly with the direction of a fluid flow.

5. The fluid flow-powered generator of claim 3, further comprising a spring system to restrain the rotation of the frame about the central axis member, wherein the rotation of the frame is constrained to an angular position between about −

π

/2 and about π

/2.

6. The fluid flow-powered generator of claim 1, further comprising:

an accelerometer located to measure the rotational rate and angular position of the frame, and a sensor to measure fluid flow speed, wherein the controller directs adjustment of the angle of attack of the first wing and the second wing based upon the rotational rate and angular position of the frame, and the fluid flow speed.

7. The fluid flow-powered generator of claim 6, wherein the controller maintains the angle of attack of the first wing and the second wing at a maximum effective angle of attack before stall.

8. The fluid flow-powered generator of claim 1, wherein the first wing and second wing are mounted to the transverse arms along the chord line at one quarter of the distance from the leading edge to the trailing edge, and wherein the first wing and second wing are pivotable about this mounting position.

9. A rotary fluid flow-powered generator, comprising:

a rotatable frame;

a first wing and a second wing, each wing having a leading edge, a trailing edge, a first end and a second end;

each wing having an adjustable angle of attack; and

a controller to direct adjustment of the angle of attack of the first wing and the second wing in a coordinated manner while the fluid flow-powered generator is in use.

10. The rotary fluid flow-powered generator of claim 9, wherein the rotatable frame comprises a central axis member, a first pair of transverse arms and a second pair of transverse arms, each pair of transverse arms extending from the central axis member, wherein the first and second pairs of transverse arms are on approximately the same plane, and wherein the first wing is mounted at its first end and second end between the first pair of transverse arms and the second wing is mounted at its first end and second end between the second pair of transverse arms.

11. The rotary fluid flow-powered generator of claim 10, wherein the central axis member is oriented in a generally vertical direction.

12. The rotary fluid flow-powered generator of claim 10, wherein the central axis member is oriented in a generally horizontal direction.

13. The rotary fluid flow-powered generator of claim 9, wherein the angle of attack of each wing is determined by the orientation of a chord line extending through the leading and trailing edges thereof, and each wing is pivotally mounted to the frame to allow the angle of attack to be adjusted.

14. The rotary fluid flow-powered generator of claim 9, further comprising:

an accelerometer located to measure the rotational rate and angular position of the frame, and a sensor to measure fluid flow speed, wherein the controller directs adjustment of the angle of attack of the first wing and the second wing based upon the rotational rate and angular position of the frame, and the fluid flow speed.

15. The rotary fluid flow-powered generator of claim 14, wherein the controller maintains the angle of attack of the first wing and the second wing at a maximum effective angle of attack before stall.

16. The rotary fluid flow-powered generator of claim 14, wherein the frame rotates through a full rotational cycle from 0 to 2π

, and wherein in the first and fourth quarters of the rotational cycle the first and second wing are maintained at an effective angle of attack having a first sign and in the second and third quarters of the rotational cycle the first and second wing are maintained at an effective angle of attack having a second sign, wherein the first sign and the second sign are opposite.

17. A method of generating electricity, comprising the steps of:

providing a fluid flow-powered generator having a rotatable frame with a central axis member, a first wing and a second wing attached to the frame, and a controller, wherein the first wing and second wing each have an adjustable angle of attack;

actively adjusting the angle of attack of the first wing and the angle of attack of the second wing in a coordinated manner;

translating the motion of the central axis member into electrical energy.

18. The method of claim 17, further comprising the steps of:

measuring the rotational rate and angular position of the frame, and the fluid flow speed; and

directing adjustment of the angle of attack of the first wing and the angle of attack of the second wing based upon the rotational rate and angular position of the frame, and the fluid flow speed.

19. The method of claim 18, wherein fluid flow-powered generator is an oscillating fluid flow-powered generator wherein the rotation of the frame is constrained to an angular position between about −

π

/2 and about π

/2, and wherein the angle of attack of the first wing and the angle of attack of the second wing are adjusted to facilitate the oscillation of the frame between the angular positions.

20. The method of claim 18, wherein the fluid flow-powered generator is a rotary fluid flow-powered generator wherein the frame rotates through a full rotational cycle from 0 to 2π

, and wherein in the first and fourth quarters of the rotational cycle the first and second wing are maintained at an effective angle of attack having a first sign and in the second and third quarters of the rotational cycle the first and second wing are maintained at an effective angle of attack having a second sign, wherein the first sign and the second sign are opposite.