SELF REGULATING WIND TURBINE

• US 20110211957A1
• Filed: 10/06/2010
• Published: 09/01/2011
• Est. Priority Date: 02/26/2010
• Status: Abandoned Application

• Current Assignee: Curt Higgins, Mark Folsom
• Original Assignee: Curt Higgins, Mark Folsom
• Inventors: Folsom, Mark, Higgins, Curt
• Application Number:
  US12/898,862
• Publication Number:
  US 20110211957A1
• Time in Patent Office: Days
• US Class Current: 416/41
• CPC Class Codes: F03D 1/0658 Arrangements for fixing wind-engaging parts to a hub
• CPC Class Codes: F03D 7/0224 Adjusting blade pitch
• CPC Class Codes: F03D 7/0236 by changing the active surface of the wind engaging parts, e.g. reefing or furling
• CPC Class Codes: F05B 2240/2022 by means of teetering or coning blades
• CPC Class Codes: F05B 2260/77 the adjusting mechanism driven or triggered by centrifugal forces
• CPC Class Codes: F05B 2260/78 the adjusting mechanism driven or triggered by aerodynamic forces
• CPC Class Codes: F05B 2260/79 Bearing, support or actuation arrangements therefor
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

A wind turbine for use in a wide range of wind conditions is disclosed. The wind turbine uses blade pitch change and/or blade folding to accommodate wind conditions and maintain a substantially constant speed. The blades are configured to fold in unison for balanced wind turbine operation.

Claims

1. A wind turbine comprising:

a rotatable hub;

a plurality of blades configured to rotate about a central axis of the hub, the plurality of blades coupled to the hub such that each blade has at least three degrees of freedom with respect to the hub, such that;

each blade is extendable along an axis parallel to a length of the blade,

each blade is configured to rotate about the axis parallel to the length of the blade, and

each blade is configured to fold in unison toward the central axis of the hub.

2. The wind turbine of claim 1, wherein a surface area of each of the plurality of blades exposed to an oncoming wind increases with an increase in the oncoming wind.

3. The wind turbine of claim 2, further comprising a weighted arm configured to bias the rotation of each of the plurality of blades about the axis parallel to the length of the blade.

4. The wind turbine of claim 1, further comprising an automatic blade pitch adjustment configured to automatically adjust a pitch angle of each of the plurality of blades to apply a reverse torque on the rotation of the plurality of blades.

5. The wind turbine of claim 4, wherein the automatic blade pitch adjustment operates concurrently with an automatic blade folding adjustment to regulate the speed of the wind turbine such that the speed is substantially constant.

6. A wind turbine comprising a plurality of blades and an automatic blade folding adjustment, the blade folding adjustment configured to regulate a speed of the wind turbine such that the speed is substantially constant,

wherein the automatic blade folding adjustment is operative to fold the plurality of blades in unison in response to oncoming wind.

7. The wind turbine of claim 6, wherein each of the plurality of blades is configured to fold in unison based on a wind force applied to at least one of the plurality of blades.

8. The wind turbine of claim 6, wherein each of the plurality of blades is configured to extend along an axis parallel to a length of the blade, based on a centrifugal force applied to the blade.

9. The wind turbine of claim 6, wherein each of the plurality of blades is configured to rotate about an axis parallel to a length of the blade.

10. The wind turbine of claim 6, further comprising at least three mechanical pivot points associated with a folding of each of the plurality of blades.

11. The wind turbine of claim 10, further comprising a tie rod associated with each of the plurality of blades, wherein the tie rod provides at least two of the at least three mechanical pivot points associated with the folding of each of the plurality of blades.

12. The wind turbine of claim 6, further comprising a shaft spring operatively coupled to the plurality of blades and configured to bias the folding of the plurality of blades.

13. The wind turbine of claim 6, further comprising one or more magnets operatively coupled to the automatic blade folding adjustment, the one or more magnets configured to control the folding of the plurality of blades.

14. The wind turbine of claim 13, wherein the one or more magnets are electromagnets.

15. The wind turbine of claim 6, further comprising an automatic blade pitch adjustment configured to automatically adjust a pitch angle of each of the plurality of blades.

16. The wind turbine of claim 15, wherein the automatic blade pitch adjustment operates concurrently with the automatic blade folding adjustment to regulate the speed of the wind turbine such that the speed is substantially constant.

17. The wind turbine of claim 15, wherein the automatic blade pitch adjustment is configured to automatically adjust a pitch angle of each of the plurality of blades such that a surface area of each of the plurality of blades exposed to oncoming wind increases with an increase in the oncoming wind.

18. The wind turbine of claim 15, wherein the automatic blade pitch adjustment is configured to automatically adjust a pitch angle of each of the plurality of blades to apply a reverse torque on the rotation of the plurality of blades.

19. The wind turbine of claim 15, further comprising a blade pitch control slot associated with each of the plurality of blades, the blade pitch control slot configured to determine a limit whereby each of the plurality of blades may extend along an axis parallel to the length of the blade and a limit whereby each of the plurality of blades may rotate about an axis parallel to the length of the blade.

20. The wind turbine of claim 19, further comprising a blade pitch guide operatively coupled to the blade pitch control slot, the blade pitch guide configured to control the pitch angle of each of the plurality of blades based on the blade pitch control slot.

21. The wind turbine of claim 15, further comprising a blade pitch spring operatively coupled to each of the plurality of blades, the blade pitch spring configured to bias the extension of each of the plurality of blades.

22. A wind turbine comprising:

a plurality of blades coupled to a hub configured to rotate about a central axis of the hub, each blade being configured to extend along an axis parallel to a length of the blade, based on a centrifugal force applied to the blade, and to rotate about the axis parallel to the length of the blade, wherein the plurality of blades are configured to fold in unison toward the central axis of the hub;

a pitch control stage configured to automatically adjust a pitch angle of each blade such that a surface area of the blade exposed to oncoming wind increases with an increase in the oncoming wind, the pitch control stage including;

a blade pitch control slot associated with each blade, the blade pitch control slot configured to determine a limit whereby each blade may extend along the axis parallel to the length of the blade and a limit whereby each blade may rotate about the axis parallel to the length of the blade;

a blade pitch guide operatively coupled to the blade pitch control slot, the blade pitch guide configured to control the pitch angle of each blade based on the blade pitch control slot; and

a blade pitch spring operatively coupled to each blade, the blade pitch spring configured to bias the extension of each blade; and

a blade folding stage comprising at least three mechanical pivot points associated with a folding of each blade, the blade folding stage configured to automatically fold each blade in unison toward the central axis of the hub based on a wind force applied to the plurality of blades, the blade folding stage, including;

a plurality of tie rods, each tie rod mechanically coupled to each blade, each tie rod providing at least two of the three mechanical pivot points associated with the folding of each blade;

a collar assembly mechanically coupled to each tie rod, the collar assembly configured to control the folding of each blade, and further configured to fold each blade in unison, based on each tie rod;

a shaft spring operatively coupled to the collar assembly, the shaft spring configured to bias the folding of the plurality of blades; and

one or more linear bearings operatively coupled to the collar assembly,

wherein the pitch control stage and the blade folding stage operate concurrently to regulate a speed of the wind turbine such that the speed is substantially constant.