WO2014192028A2

WO2014192028A2 - Reconfigurable mechanism for wind turbine blades

Info

Publication number: WO2014192028A2
Application number: PCT/IN2014/000362
Authority: WO
Inventors: Riyaz RAFIQUE; Prashant BAREDAR
Original assignee: Rafique Riyaz
Priority date: 2013-05-30
Filing date: 2014-05-29
Publication date: 2014-12-04
Also published as: WO2014192029A3; WO2014192029A2; WO2014192028A3

Abstract

The present disclosure discloses a reconfigurable mechanism for wind turbine blades. The wind turbine is provided with only a single actuator for reconfigurable mechanism which is adapted for expansion and contraction of blades. The reconfigurable mechanism for wind turbine blades comprises at least one wind turbine assembly, at least a plurality of blade, at least a linkage mechanism, at least one slider block, at least one slider link, at least one powering unit, at least one transmission mechanism, at least one generator and a frame. The frame supports at least one wind turbine assembly. Said at least one powering unit is isolated from said wind turbine assembly, wherein rotational motion of said wind turbine assembly is independent of motion transmission from said at least one powering unit to said slider link.

Description

RECONFIGURABLE MECHANISM FOR WIND TURBINE BLADES

FIELD OF THE INVENTION

The present invention relates to the field of wind turbine.

Particularly, the present invention relates to the field of reconfigurable mechanism for varying diameter of wind turbine blades.

Particularly, the present invention relates to the field of vertical axis wind turbine and horizontal axis wind turbine. BACKGROUND OF THE INVENTION

Wind turbines create power proportional to the swept area of their blades. Wind turbines having longer blades will increase the swept area, which in turn produces more power. At high wind speeds, a wind turbine having longer blades places greater demands on the components and creates more situations where the turbine must be shut down to avoid damaging components. Even in situations where the average wind speed is not high enough to cause damage, periodic wind gusts apply forces that may be strong enough to damage equipment. Accordingly, choosing a rotor diameter for a wind turbine has conventionally been a design trade-off between longer blades for more energy production in low winds and shorter blades for load limitation in high Winds.

Variable length rotor blade systems have also been used in an attempt to achieve higher power, and experience fewer shut downs and less damage to components. In such systems, the wind turbine rotor blades are telescopic so that their length can be adjusted based on the wind speed. The rotor blades can be extended to provide higher output in low wind conditions and retracted to lower loads in high wind conditions. US. Pat. No. 6,902,370 discloses a wind turbine system having telescoping wind turbine rotor blades. Conventional wind turbines are difficult to transport assembled as they are bulky, complex, and design is less user friendly. Hence, conventional wind turbines require assembling on site which requires huge resources.

1 Conventional mechanism for variable diameter wind turbine are not dynamically balanced, are not reconfigurable with single degree of freedom and compels to lots of components and or actuators to be rotated with the wind turbine which leads to less power generation.

OBJECTS OF THE INVENTION

Some of the objects of the system of the present disclosure, which at least one embodiment herein satisfies, are as follows:

An object of the present invention is to provide a wind turbine which can expand and contract the diameter of blades and utilizes least number of motors for high power generation safely and for ease in transportation.

An object of the present invention is to provide a turbine which can be configured differently, manually or automatically, for varying diameter of blades.

An object of the present invention is to provide a wind turbine in which only a single actuator for reconfigurable mechanism is utilized for expansion and contraction of blades. An object of the present invention is to provide a wind turbine in which weight of blades and all the components rotating with the blades, in all states of blades must be evenly distributed with better power management, while simplifying the drive-train.

An object of the present invention is to provide a wind turbine which is easy to operate and control for varying diameter of blades.

An object of the present disclosure is to provide a wind turbine which is safe, smooth, convenient, light weight, portable and user friendly.

Other objects and advantages of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures, which are not intended to limit the scope of the present disclosure.

SUMMARY OF THE INVENTION

In accordance with the present disclosure there is provided a reconfigurable mechanism responsible for expanding and contracting a polygon, circular form or say blades with any form for wind turbine. Wind turbine with varying diameter blades is reconfigurable with single degree of freedom mechanism. One of the applications is a wind turbine having at least one pair of blades adapted to vary the diameter to enable for high power generation and to be portable in closed position with least diameter.

The powering unit for varying diameter mechanism is independent of rotational motion ofrotor.

Variable-diameter wind turbine rotor blades offer a way to achieve higher power output in low wind conditions and to avoid equipment damage in high wind conditions.

The diameter of wind turbine can be adapted to be expanded or contracted based on the wind speed measured from an anemometer or any sensor or by the power produced by the generator.

BRIEF DESCRIPTION OF DRAWINGS

So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter that is regarded as the present invention, it is believed that the invention will be more fully understood from the following description taken in conjunction with the accompanying drawings. None of the drawings are necessarily to scale.

The wind turbine of the present disclosure will now be described with the help of accompanying drawings, in which:

FIG. 1 illustrates a closed blade mechanism which can be fitted on a wind turbine in accordance with the present invention;

FIG. 2 illustrates an interim position while expanding blade of mechanism shown in FIG. 1; FIG. 3 illustrates an expanded blade of the mechanism shown in FIG. 1;

FIG. 4 illustrates different states of a single blade;

FIG. 5 illustrates an exact straight line mechanism while blade is closed;

FIG. 6 illustrates an exact straight line mechanism showing all states;

FIG. 7 illustrates an exact straight line mechanism while blades are closed;

FIG. 8 illustrates an exact straight line mechanism for only two blades;

FIG. 9 illustrates an isometric view of mechanism for Slider Link;

FIG. 10 illustrates an isometric view of slider link mechanism with mounting block;

FIG. 11 illustrates a close view of slider link mechanism by removing left conical cover or left hollowed section when blades are closed;

FIG. 12 illustrates a close view of slider link mechanism by removing conical cover or left hollowed section while interim position of expanding blades;

FIG. 13 illustrates a close view of slider link mechanism by removing conical cover or left hollowed section while expanded blades;

FIG. 14 illustrates an alternate slider link mechanism as shown in FIG.9;

FIG. 15 illustrates an alternate arrangement of slider link mechanism with mounting block as shown in FIG.10;

FIG. 16 illustrates a connecting link and a blade with two holes for pivoting blade and connecting link;

FIG. 17 illustrates a connecting link pivoted with a link element with a pin;

FIG. 18 illustrates a blade with only a hole to couple with pin of link element;

FIG. 19 illustrates an isometric view of expanded blades in which each blade is coupled with each pin of link element and linkage mechanism is fully covered ;

FIG. 20 illustrates a closed blade mechanism with different blade as shown in FIG. 1 ; FIG. 21 illustrates an interim position while expanding blades of mechanism shown in

FIG. 20;

FIG. 22 illustrates an isometric view of wind turbine with interim position while expanding blades;

FIG. 23 illustrates an isometric view of wind turbine with two sets of expanding blades at interim position placed at different planes; FIG. 24 illustrates a top view of wind turbine where two sets of expanding blades at interim position are either placed at different planes or one is placed internally and other is placed externally rotating in same direction.

FIG. 25 illustrates a top view of wind turbine where two sets of expanding blades at interim position are either placed at different planes or one is placed internally and other is placed externally rotating in different directions.

DETAILED DESCRIPTION OF THE INVENTION WITH THE ACCOMPANYING DRAWINGS

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

Figure 1 is a conceptual illustration of closed wind turbine 1. Here 2 is the centre of the wind turbine. And, the each connecting links 3, 4, 5 and 6 are connected pivotally with the each individual blades 7, 8, 9 and 10 respectively of the wind turbine 1. In total there are four connecting links 3,4,5 and 6 and , circumference of wind turbine 1 is divided into four segments or say blades 7,8,9 and 10 . Individual blades 7, 8, 9 and 10 is pivoted at one end 16, 17, 18 and 19 respectively with the profiled outer plate 15.

For expanding the wind turbine 1 one ends 1 1, 12, 13 and 14 of the connecting links 3, 4, 5 and 6 respectively is pivoted to the blades of the wind turbine 1 and other ends 20, 21, 22 and 23 is shifted away from the centre of the wind turbine. Shifting of other ends 20, 21, 22 and 23 away from the centre of the wind turbine should be done simultaneously for all the connecting links. For example, here 20 of the above connecting link 3 is shifted above as shown with arrow and 21 of the below connecting link 4 is shifted below as shown with arrow. In the same way left and right side of the connecting links 6 and 5 are shifted accordingly, for expanding the wind turbine 1.

Figure 2 is a conceptual illustration of interim position while expanding wind turbine 1. Here interim position while expanding wind turbine 1 is shown with centre of the wind turbine as 2. Here, connecting link end initial position 20 have further shifted to new position 28 and 21 have further shifted to new position 29. In the same way left and right side of the connecting links 6 and 5 are shifted accordingly.

Figure 3 is a conceptual illustration of expanded wind turbine. Here expanded wind turbine 1 is shown with centre of the wind turbine as 2. Here, position 28 has further shifted to new position 30 and position 29 has further shifted to new position 31. In the same way left and right side of the connecting links 6 and 5 are shifted accordingly. Reconfigurable mechanism is broadly constituents of following mechanisms:- Linkage mechanism - This mechanism provides motion to the connecting link. This mechanism transforms the straight line motion into rotational motion of blades (segment of the circumference of the wind turbine) for expanding wind turbine diameter.

Mechanism for Slider link - This mechanism provides motion to the slider block, which transmits input motion to the above said linkage mechanism. This mechanism transforms the rotational motion of screw threaded shaft into translatory motion of nut.

Mechanism for slider link as stated above can be replaced by many other mechanisms for providing linear motion to the slider block 61 which is pivotally connected with the slider link 62. One replacement of this mechanism is conventional slider crank mechanism, where the role of crank is done by a gear (crank gear), and over the face of same crank gear is pivoted connecting rod at one end. And, at the other end of connecting rod is connected slider link (which is constrained to move linearly). Rotation of crank gear gives reciprocating motion of slider link. And half rotation of crank gear will open the wind turbine and the slider link is pivotally connected with the slider block which powers the exact straight line mechanism for expanding the wind turbine. Hence, other half rotation of crank gear will contract the wind turbine and will bring back into closed wind turbine position. Said crank gear can be powered by a second gear powered by motor.

Mechanism for varying wind turbine diameter is further mentioned here. Different states of a single blade 7 of proposed wind turbine 1 are illustrated in Figure 4. Here, closed wind turbine position 32 with centre of the wind turbine as 2 is shown. To achieve interim position 33 while expanding wind turbine 1 , end 20 of connecting link 3 have to be further shifted to 28. And, finally to achieve expanded wind turbine position 34, end 20 of connecting link have to be further shifted to 30. In the same way all the connecting links 3, 4, 5 and 6 are shifted accordingly away from the centre 2 of wind turbine 1. This figure clearly illustrates that exact straight line motion can deliver the desired motion. In the Figure 5, exact straight line mechanism while wind turbine 1 is closed is illustrated. The above mechanism can be referred as the Scott Russell Mechanism or a more descriptive name is the Scott Russell Exact Straight Line Mechanism. For this description to be true the acting length of the short link 39, needs to be half as long as the active length of the long link 40 and the pin 37 that connects them must be concentric with the midpoint of the long link 40. One more requirement is that the connection pin of slider link 41 needs to be sliding in a line that would intersect the static pivot end 38 of the short link 39.

In the Figure 6, 36 is shifted to 47 when slider link 41 is pushed in the direction of 36 to 38. Hence, initial position of connecting link end 20 is shifted to 28 in the direction of 38 to 28. In this way the interim position 33 while expanding wind turbine 1 is achieved. In the same way, connecting link end 28 is further shifted to 30 when slider link 41 is further pushed in the direction of 47 to 48. In this way the expanded wind turbine position 34 is achieved. In the Figure 6, all the states of exact straight line mechanism is illustrated. It is clear from this figure that shifting of slider link 41 in left expands the wind turbine diameter whereas shifting in right will contract the wind turbine diameter. In the Figure 7, exact straight line mechanism which is utilized to transfer motion away from the centre of the wind turbine 2 is represented. Slider link 41 is either pulled or pushed in the direction of 51 to 2 for expanding or 2 to 51 for contracting wind turbine. Here, 36 to 100 is slider block 41 which is pivoted over the slider link 41 at 51. And, static pivot end of the short link 39 is 101 and similarly for short link 53 is 54. Same is explained elaborately in Figure 8.

In the Figure 8, right side of imaginary line 49 to50 represents exact straight line mechanism which is utilized to transfer motion away and near from the centre of the wind turbine 2 on individual connecting links (here shown only 3 and 4 for ease in clarity) pivoted with each blade of wind turbine 7 and 8 respectively. Slider link 41 is either pulled or pushed in the direction of 51 to 2 for expanding or 2 to 51 for contracting wind turbine. Here, 36 to 100 is slider block 41 which is pivoted over the slider link 41 at 51. And, static pivot end of the short link 39 is 101 and similarly for short link 53 is 54. All the static pivot ends of the short links are adapted to be pivoted with outer plate 15. Left side of imaginary line 49, 50 represents two blades 7 and 8 of the wind turbine 1, and is on different plane than exact straight line mechanism shown at right side of imaginary line 49, 50. Only two of the blades 7 and 8 are shown here for avoiding any misinterpretation. Blade 7 shown above is pivoted with outer plate 15 at point 16 whereas blade 8 shown below is pivoted with outer plate 15 at point 17.

In the Figure 9, mechanism to provide linear motion for slider block 61 is illustrated. Mechanism for slider link is composed of shaft 55 with screw thread 56 (which is rotated) and cuboidal nut 57 (constrained to move only linear motion) with internal thread, which transforms rotational motion to linear motion. Shaft 55 with screw thread 56 is rotated which transmits linear motion to the cuboidal nut 57. Cuboidal nut 57 is constrained to move only linearly as one of its side is rolled over a pivotally mounted roller 58, which is mounted with supports 59 at both ends which are fixed with frame 60 (not shown in Fig. 9). Slider block 61 is pivotally mounted over the slider link 62 at one end where as cuboidal nut 57 is connected over the other end of slider link 62. Slider block 61 further delivers motion to the exact straight line mechanism. And, long link 40 and all long links are pivotally connected with this slider block 61 at one end and at the other end adapted to be pivotally connected with connecting links 3, 4, 5 and 6 at ends 20, 21, 22 and 23. To consider wind turbine rotation, rotation of said wind turbine should be independent from wind turbine expansion, so for actuating wind turbine expansion here it is embedded a shaft 55 with screw thread 56 further extended into a hollowed mounting block 63 which pivotally supports wheel gear 65 at embossed surface 64. At other end of wheel gear 65 disc of conical cover 66 is connected. Disc of conical cover 66 is connected with one end of conical cover 67 whereas inner plate 68 is connected at the other end of conical cover 67. The torque obtained by rotational motion of wheel gear 65 or say wind turbine assembly 1 is adapted to generate electricity through generator 104. A schematic of basic concept of this is shown in Figure 9. Mounting Block 63 is shown in Figure 10 in detail by shifting wheel gear 65 and disc 66 of sectional cover or say conical cover 67 aside and removing all other attachments. Mounting Block 63 is fixed with the frame 60 and is hollowed and adapted to pass the shaft 55 and slider link 62. Embossed surface 64 over mounting block 63 is utilized to pivotally mount the wheel gear 65 and disc of sectional cover 66. Slider block 61 is pivotally mounted over the slider link 62 which is connected with the cuboidal nut 57. Motor 105 is coupled with gear 205, said gear 205 is meshed with gear 305 mounted over the shaft 55. Said motor 105 is adapted to be powered to vary the diameter of wind turbine 1.

Shaft 55 is pivotally mounted with the help of plummer blocks 99 and 399. Generator 104 which is clamped with the frame 60 with clamps 101. Gear 201 is coupled with generator 104, which is meshed with wheel gear 65.Thus, generator 104 is adapted to generate electricity.

In the Figure 14, an alternate slider link mechanism as shown in Figure 9 is shown. Here, link 501 is coupled with slider link 62 at one end and with nut 757 at other end. Slider block 61 is adapted to be pivotally mounted over the said slider link 62.

In the Figure 15, an alternate arrangement as shown in Figure 10 of slider link mechanism with mounting block 63 is shown. Mounting block 63 is adapted to support rotatably shaft 55 and two further holes are adapted to pass the link 501 of slider link shown in Figure 14.

In the Figure 16, a connecting link 3 and a blade 7 with two holes for pivoting blade 7 and connecting link 3 is shown. In the Figure 17, a connecting link 3 is pivoted with a link element 510 with a pin at pivoted point 16. In the Figure 18, a blade 7 with only a hole to couple with said pin of link element 510 at different plane is shown.

In the Figure 19, an isometric view of expanded wind turbine 1 in which each blade is coupled with each pin of link element and linkage mechanism is fully covered by cover 777 to eliminate any blockage in operation due to entering foreign objects such as dust and dirt etc.

In the Figure 20, an alternate arrangement of a closed wind turbine 1 is shown where blade 565 is stacked one over the other either on same plane or different planes to enable maximum varying wind turbine diameter. In the Figure 21 , an interim position while expanding wind turbine 1 as mentioned above in Figure 20 is shown.

In the Figure 22, an isometric view of wind turbine 1 with another arrangement 61 1 with interim position while expanding blades 609 and linkage mechanisms fully covered by cover 777.

In the Figure 23, an isometric view of wind turbine 1 with one blade arrangement 611 and another blade arrangement 612 with two sets of expanding blades at interim position placed at different planes;

In the Figure 24, a top view of wind turbine 1 where two sets of expanding blade arrangements 609 and 612 at interim position are either placed at different planes or one is placed internally and other is placed externally rotating in same direction.

In the Figure 25, a top view of wind turbine 1 where two sets of expanding blade arrangements 609 and 612 at interim position are either placed at different planes or one is placed internally and other is placed externally rotating in different directions.

The diameter of wind turbine can be adapted to be expanded or contracted based on the wind speed measured from an anemometer or by the power produced by the generator. The axis of wind turbine assembly is either vertical axis or horizontal axis.

In the foregoing specification, specific embodiments of the present invention have been described. However, one of ordinary skill in the art will appreciate that various modifications and changes can be made without departing from the spirit and scope of the present invention as set forth in the various embodiments discussed above. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present invention. The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements as described herein.

Claims

I claim:

1. A reconfigurable mechanism for wind turbine blades having at least a pair of blades adapted to vary wind turbine diameter, said mechanism comprising:

• at least a wind turbine assembly having at least one profiled plate defining a plurality of blade fixing portions adapted to rotatably fix a plurality of blades about said plurality of blade fixing portions, each of said profiled plate adapted to be rotatably mounted on at least one coaxial shaft;

• at least a linkage mechanism adapted to transmit motion to said plurality of blades through at least one slider block;

• said at least one slider block adapted to be rotatably mounted on at least a slider link, said slider link is adapted to be coaxially mounted on said coaxial shaft;

• at least one powering unit, said at least one powering Unit is isolated from said wind turbine assembly, wherein rotational motion of said wind turbine assembly is independent of motion transmission from said at least one powering unit to said slider link;

• at least one transmission mechanism adapted to transmit motion from said at least one powering unit to said slider link to enable diameter variation of said wind turbine assembly;

• a frame adapted to support said wind turbine assembly, said frame adapted to support at least a drive arrangement adapted to transmit motion from said powering unit to said transmission mechanism; and

• at least one electricity generating unit, said electricity generating unit adapted to generate electricity from rotational motion of said at least one wind turbine assembly, wherein said electricity generating unit is adapted to be supported by said frame.

2. The mechanism as claimed in claim 1 , wherein said linkage mechanism is having at least one long link, at least one short link is adapted to be pivotally coupled with midpoint of said at least one long link, wherein one end part of said at least one long link is adapted to transmit motion to said plurality of blade and other end part of said at least one long link is adapted to be pivotally coupled with said at least one slider block, said at least one short link is adapted to be pivotally coupled with said at least one profiled plate at other end part , wherein said at least one slider link needs to be sliding in a line that would intersect static pivot end of said at least one short link.

3. The mechanism as claimed in claim 2, wherein said linkage mechanism further includes at least one connecting link, said at least one long link is adapted to transmit motion to said at least one blade through said at least one connecting link.

4. The mechanism as claimed in claim 1, wherein said transmission mechanism is adapted to convert rotary motion of said at least one powering unit to linear motion of said slider link.

5. The mechanism as claimed in claim 1, wherein said at least one powering unit is selected from the group consisting of manually operated unit and motor operated unit.

6. The mechanism as claimed in claim 1, wherein said at least one powering unit is selected from the group consisting of semi automatically operated unit and automatically operated unit.

7. The mechanism as claimed in claim 1, wherein axis of said at least one wind turbine assembly is selected from the group consisting of vertical axis and horizontal axis.

8. The mechanism as claimed in claim 1 , wherein said at least a pair of blade is stacked one over the other, wherein plane of stacking of said at least a pair of blade is selected from the group of plane consisting of same plane and different plane to enable maximum varying wheel diameter.

9. The mechanism as claimed in claim 1 , wherein said at least one wind turbine assembly is located within said at least one another wind turbine assembly.

10. The mechanism as claimed in claim 1 , wherein variation of diameter of said at least one wind turbine assembly on the basis of wind speed measured is selected from the group consisting of measured from an anemometer and measured by power produced.