A vertical axis wind turbine adaptive variable airfoil device based on wind vane and cam linkage

Abstract

This invention relates to an adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam. It includes a generator drive shaft and a support column. A vertical wind turbine rotor is fixedly connected to the upper part of the generator drive shaft extending from the support column. The wind turbine rotor includes a hub fixedly attached to the generator drive shaft. Several annularly distributed vertical airfoil blades are arranged around the hub. Each airfoil blade includes a trailing edge and a leading edge. The front end of the leading edge and the rear end of the trailing edge are hinged together. The trailing edge is fixed to the outer end of a blade mounting rod, and the inner end of the blade mounting rod is fixed to the hub. A grooved cam disk is provided on the support column below the hub, and a cam groove is formed on the grooved cam disk outside the generator drive shaft. This device designs the airfoil blades of the vertical axis wind turbine as having a movable leading edge. Based on the mechanical control of the cam, the leading edge is periodically adjusted to achieve the angle of attack for maximum lift generated by the airfoil blades, thereby improving the power generation efficiency of the vertical axis wind turbine.

Description

Technical Field

[0001] This invention relates to the technical field of wind turbines, and more specifically to an adaptive variable airfoil device for a vertical axis wind turbine based on the linkage between a wind vane and a cam. Background Technology

[0002] A vertical axis wind turbine is a wind power generation device whose rotor axis is perpendicular to the ground or the airflow direction. Its structure includes a tower, main shaft, blades, generator set, and control system. It features low wind speed start-up (1 m / s), no need for wind direction adjustment, and no noise. Currently, many vertical axis wind turbines use airfoil blades as their generating blades. However, these airfoil blades are generally fixed structures. During rotation, the angle of attack of the airfoil blades in a vertical axis wind turbine changes drastically with the azimuth angle. Fixed airfoils are in a stall or inefficient state at most azimuth angles. Therefore, some have proposed designing a movable structure for the leading edge of the airfoil blade, meaning the angle of the leading edge can be adjusted. The core idea is to adjust the leading edge camber in real time so that the blade maintains an optimal angle of attack that generates maximum lift at any azimuth angle. This is equivalent to installing a "smart flap" on each blade, whose deflection is periodic and a function of the azimuth angle. Therefore, it is necessary to design an airfoil blade with a periodically adjustable leading edge to improve the power generation efficiency of the vertical axis wind turbine. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing an adaptive variable airfoil device for vertical axis wind turbines based on the linkage of a wind vane and a cam. This device designs the airfoil blades of the vertical axis wind turbine as having a movable leading edge, and uses mechanical control based on the cam to periodically adjust the angle of the leading edge, thereby achieving the angle of attack at which the airfoil blades generate maximum lift and improving the power generation efficiency of the vertical axis wind turbine.

[0004] An adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam includes a power generation drive shaft and a support column of the vertical axis wind turbine. The power generation drive shaft is connected to the support column via bearings. The upper part of the power generation drive shaft extends out of the support column and is fixedly connected to a vertical wind turbine impeller. The wind turbine impeller includes a hub that is fixedly connected to the power generation drive shaft. Several annularly distributed vertical airfoil blades are provided around the hub. The airfoil blades include a trailing edge and a leading edge. The front end of the leading edge and the rear end of the trailing edge are hinged together. The trailing edge is fixed to the outer end of the blade mounting rod, and the inner end of the blade mounting rod is fixed to the hub.

[0005] A grooved cam disk is provided on the support column below the hub, and a cam groove is formed on the grooved cam disk on the outside of the generator drive shaft; a guide seat is fixed to the blade mounting rod, and a cam connecting rod is inserted into the guide seat. A roller is hinged to the inner end of the cam connecting rod through a pin, and the roller is inserted into the cam groove of the grooved cam disk. A leading edge connecting rod is hinged to the outer end of the cam connecting rod through a pin, and the outer end of the leading edge connecting rod is hinged to the leading edge.

[0006] The cam groove on the grooved cam disk consists of a first arc-shaped groove that gradually deflects from the outside to the inside, a second arc-shaped groove that rapidly deflects from the inside to the outside and quickly changes direction, a third arc-shaped groove that gradually deflects from the inside to the outside, and a fourth arc-shaped groove that gradually deflects from the inside to the outside.

[0007] Preferably, the leading edge of the airfoil blade has a hinge post with a horizontal cross-section of a circle at the front end, and arc-shaped hinge grooves are formed on the trailing edges on both sides of the hinge post; the leading edge has a slot with a horizontal cross-section of a circle at the rear end, and arc-shaped hinge pieces are formed on the leading edges on both sides of the slot, the hinge pieces are respectively inserted into the arc-shaped hinge grooves of the trailing edge, and the hinge post of the trailing edge is inserted into the slot of the leading edge.

[0008] The cam groove is formed on the upper end face of the grooved cam disk, and a vertical hinge support shaft is inserted and fixed on the rear edge. The end of the hinge support shaft is hinged to the front edge connecting rod.

[0009] Preferably, the leading edge connecting rod has two sets, upper and lower, distributed on the upper and lower sides of the airfoil blade, and a vertical linkage rod is fixedly connected to the cam connecting rod.

[0010] Preferably, the width of the cam groove on the grooved cam disk is equal to the diameter of the roller.

[0011] Preferably, a wind vane is fixed to the lower end of the grooved cam disk, and the wind vane is located below the wind turbine impeller;

[0012] The upper end of the support column is formed with a connecting shaft, and the grooved cam disk is connected to the connecting shaft through a bearing.

[0013] Preferably, the pitch angle of the trailing edge is 2° to 4°.

[0014] The beneficial effects of this invention are as follows:

[0015] This device designs the airfoil blades of the vertical axis wind turbine as having a movable leading edge. Based on the mechanical control of the cam, the leading edge is periodically adjusted to achieve the angle of attack at which the airfoil blades generate maximum lift, thereby improving the power generation efficiency of the vertical axis wind turbine. Attached Figure Description

[0016] Figure 1 This is a partial cross-sectional view of the present invention from the frontal view.

[0017] Figure 2 This is a top-view cross-sectional diagram of the present invention;

[0018] Figure 3 for Figure 2 A magnified view of a portion of point A in the middle.

[0019] Figure 4 This is a top-view structural diagram of the grooved cam disk in this invention.

[0020] In the diagram: 1. Generator drive shaft; 2. Support column; 21. Connecting shaft; 3. Hub; 4. Blade mounting rod; 5. Airfoil blade; 51. Trailing edge; 52. Leading edge; 6. Groove cam disk; 61. Cam groove; 7. Cam connecting rod; 8. Roller; 9. Guide seat; 10. Leading edge connecting rod; 11. Wind vane; 12. Linkage rod. Detailed Implementation

[0021] Example: See Figures 1 to 4 As shown, an adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam includes a power generation drive shaft 1 and a support column 2 of the vertical axis wind turbine. The power generation drive shaft 1 is connected to the support column 2 via bearings. A vertical wind turbine impeller is fixedly connected to the upper part of the power generation drive shaft 1 extending out of the support column 2. The wind turbine impeller includes a hub 3 fixedly connected to the power generation drive shaft 1. Several vertically arranged airfoil blades 5 are evenly distributed in annular rings around the hub 3. The airfoil blades 5 include a trailing edge 51 and a leading edge 52. The front end of the leading edge 52 and the rear end of the trailing edge 51 are hinged together. The trailing edge 51 is fixed to the outer end of the blade mounting rod 4. The inner end of the blade mounting rod 4 is fixed to the hub 3.

[0022] A grooved cam disk 6 is provided on the support column 2 below the hub 3, and a cam groove 61 is formed on the grooved cam disk 6 on the outer side of the generator drive shaft 1; a guide seat 9 is fixedly connected to the blade mounting rod 4, and a cam connecting rod 7 is inserted into the guide seat 9. A roller 8 is hinged to the inner end of the cam connecting rod 7 through a pin. The roller 8 is inserted into the cam groove 61 of the grooved cam disk 6. A leading edge connecting rod 10 is hinged to the outer end of the cam connecting rod 7 through a pin. The outer end of the leading edge connecting rod 10 is hinged to the leading edge 52.

[0023] The cam groove 61 on the grooved cam disk 6 is composed of a first arc groove 611 that gradually deflects from the outside to the inside, a second arc groove 612 that rapidly deflects from the inside to the outside and quickly changes direction, a third arc groove 613 that gradually deflects from the inside to the outside, and a fourth arc groove 614 that gradually deflects from the inside to the outside.

[0024] The airfoil blade 5 has a hinge post 511 with a horizontal cross-section and a circular shape at the front end of its trailing edge 51. Arc-shaped hinge grooves 512 are formed on the trailing edges 51 on both sides of the hinge post 511. The leading edge 52 has a slot 521 with a horizontal cross-section and a curved hinge piece 522 on the leading edges 52 on both sides of the slot 521. The hinge piece 522 is inserted into the arc-shaped hinge groove 512 of the trailing edge 51, and the hinge post 511 of the trailing edge 51 is inserted into the slot 521 of the leading edge 52. The airfoil blade 5 with the above structure is hinged together through the slot structure, so that the trailing edge 51 and the leading edge 52 are effectively connected together, which can effectively reduce the wind resistance on the windward surface of the airfoil blade 5.

[0025] The cam groove 61 is formed on the upper end face of the grooved cam disk 6. A vertical hinge support shaft is inserted and fixed on the trailing edge 51. The end of the hinge support shaft is hinged to the leading edge connecting rod 10. The leading edge connecting rod 10 does not contact the windward surface of the airfoil blade 5, which can reduce interference.

[0026] The leading edge connecting rod 10 is provided with two sets, upper and lower, distributed on the upper and lower sides of the airfoil blade 5. A vertical linkage rod 12 is fixedly connected to the cam connecting rod 7. The upper and lower ends of the leading edge 52 are controlled by the cam connecting rod 7, which can improve the stability of the angle adjustment of the leading edge 52.

[0027] The width of the cam groove 61 on the grooved cam disk 6 is equal to the diameter of the roller 8, so that the roller 8 matches the cam groove 61 and reduces the wobbling of the leading edge 52 on the trailing edge 51.

[0028] The upper end of the support column 2 is formed with a connecting shaft 21, and the grooved cam disk 6 is connected to the connecting shaft 21 through a bearing; a wind vane 11 is fixed to the lower end of the grooved cam disk 6. The wind vane 11 is located below the wind turbine, so that the wind vane 11 will not interfere with the wind turbine. At the same time, the distribution position of each arc groove on the cam groove 61 on the grooved cam disk 6 is automatically controlled based on the wind vane 11, thereby improving the power generation efficiency of the wind turbine.

[0029] The pitch angle of the trailing edge 51 is 2° to 4°, which is the mounting angle of the trailing edge 51. Figure 2 Taking the schematic diagram as an example, the pitch angle of the trailing edge 51 is the chord line of the trailing edge 51 and... Figure 2 The angle between the horizontal planes in the left and right directions has an optimal pitch angle of 4°; the mounting angle of the trailing edge 51 and the movable leading edge 52 work in tandem, with the mounting angle of the trailing edge 51 serving as the impeller's reference angle of attack, determining the position of the leading edge 52 in a "neutral" position. Figure 2When the leading edge 52 is at its uppermost position, the blade's basic aerodynamic performance throughout the entire rotation cycle is measured. The leading edge 52 is dynamically and periodically fine-tuned based on the reference angle of attack to optimize the instantaneous angle of attack at each azimuth angle.

[0030] When the blade is rotating, its average effective angle of attack is a positive value. An installation angle of 4° is closer to this average value. This means that the movable leading edge only needs to make small adjustments most of the time to achieve the optimal angle of attack, rather than making extreme large deflections. This reduces the load and energy consumption of the mechanism.

[0031] Working principle: This structure is an adaptive variable airfoil device for vertical axis wind turbines based on the linkage between the wind vane and the cam. The device has the following three technical points: the first is the movable leading edge 52 structure; the second is the cam groove 61 layout structure, which can generate the effective maximum lift angle by periodically rotating the leading edge 52; the third is the cam groove 61 layout structure that is adaptive to the wind direction.

[0032] First, regarding the movable leading edge 52, the leading edge 52 is hinged to the trailing edge 51, and the trailing edge 51 is fixed to the blade mounting rod 4. When the airfoil blade 5 rotates due to wind force, it will drive the guide seat 9 on the blade mounting rod 4 to move together. That is, the leading edge 52 and the guide seat 9 on the airfoil blade 5 revolve synchronously, which will drive the cam connecting rod 7 and the leading edge connecting rod 10 to move together. Due to the restriction of the cam groove 61, the cam connecting rod 7 will also slide on the guide seat 9, and then the leading edge 52 will rotate at an angle on the trailing edge 51 through the leading edge connecting rod 10.

[0033] Secondly, regarding the layout structure of the cam groove 61, such as Figure 4 As shown, its cam groove 61 consists of four arc-shaped grooves. The wind turbine rotates counterclockwise in the top view. The four arc-shaped grooves of its cam groove 61 can be set as quadrants I, II, III, and IV, respectively. Quadrant I is the driving zone, quadrant II is the maximum driving zone, quadrant III is the drag zone, and quadrant IV is the preparation zone. Its set windward direction is... Figure 2 At the very top, the azimuth angle of the very top is 0°, combined with Figure 2 The state of each airfoil 5 is used to describe the changes in the quadrant region, and the state is shown in the table below;

[0034] Azimuth (θ) Quadrant Aerodynamic targets Direction of leading edge deflection Impact on angle of attack 0° - 90° I Generate positive lift Turn inward (towards the center) Effectively increases angle of attack and optimizes lift generation 90° - 180° II Generate maximum lift torque Deflecting outwards (away from the center) Compensate for the loss of angle of attack due to trajectory velocity, and maintain a large angle of attack. 180° - 270° III Minimize headwind resistance Turn inward (towards the center) This allows the airfoil to "follow the flow," greatly reducing negative torque. 270° - 360° IV Preparing to enter the next cycle Gradually return to the correct direction from internal bias. Smooth transition to the initial state, preparing for the 0° position.

[0035] Furthermore, the wind vane 11 enables the grooved cam disk 6 to adapt to the wind direction, meaning that the azimuth angle on the cam groove 61 is 0° and can face the wind direction directly.

[0036] The embodiments described are illustrative of the invention and are not intended to limit the invention. Any person skilled in the art can modify the embodiments without departing from the spirit and scope of the invention; therefore, the scope of protection of the invention should be as set forth in the claims.

Claims

1. An adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam, comprising a power generation drive shaft (1) and a support column (2) of a vertical axis wind turbine, wherein the power generation drive shaft (1) is connected to the support column (2) via bearings, and a vertical wind turbine impeller is fixedly connected to the upper part of the power generation drive shaft (1) extending out of the support column (2), the wind turbine impeller comprising a hub (3) fixedly connected to the power generation drive shaft (1) by a sleeve, and a plurality of uniformly distributed vertical airfoil blades (5) are provided around the hub (3), characterized in that: The airfoil blade (5) includes a trailing edge (51) and a leading edge (52). The front end of the leading edge (52) and the rear end of the trailing edge (51) are hinged together. The trailing edge (51) is fixed to the outer end of the blade mounting rod (4), and the inner end of the blade mounting rod (4) is fixed to the hub (3). A grooved cam disk (6) is provided on the support column (2) below the hub (3), and a cam groove (61) is formed on the grooved cam disk (6) on the outside of the generator drive shaft (1); a guide seat (9) is fixedly connected to the blade mounting rod (4), and a cam connecting rod (7) is inserted into the guide seat (9). A roller (8) is hinged to the inner end of the cam connecting rod (7) through a pin. The roller (8) is inserted into the cam groove (61) of the grooved cam disk (6), and a leading edge connecting rod (10) is hinged to the outer end of the cam connecting rod (7) through a pin. The outer end of the leading edge connecting rod (10) is hinged to the leading edge (52). The cam groove (61) on the grooved cam disk (6) is composed of a first arc groove (611) that gradually deflects from the outside to the inside, a second arc groove (612) that deflects rapidly from the inside to the outside and changes direction rapidly, a third arc groove (613) that gradually deflects from the inside to the outside, and a fourth arc groove (614) that gradually deflects from the inside to the outside. The airfoil blade (5) has a hinge post (511) with a horizontal cross-section of a circle formed at the front end of the upper trailing edge (51), and arc-shaped hinge grooves (512) formed on the trailing edge (51) on both sides of the hinge post (511); the front edge (52) has a slot (521) with a horizontal cross-section of a circle formed at the rear end, and arc-shaped hinge pieces (522) formed on the front edge (52) on both sides of the slot (521). The hinge pieces (522) are respectively inserted into the arc-shaped hinge grooves (512) of the trailing edge (51), and the hinge post (511) of the trailing edge (51) is inserted into the slot (521) of the front edge (52). The cam groove (61) is formed on the upper end face of the grooved cam disk (6), and a vertical hinge support shaft is inserted and fixed on the rear edge (51). The end of the hinge support shaft is hinged to the front edge connecting rod (10).

2. The adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam, as described in claim 1, is characterized in that: The leading edge connecting rod (10) is provided with two sets, upper and lower, and distributed on the upper and lower sides of the airfoil blade (5). A vertical linkage rod (12) is fixedly connected to the cam connecting rod (7).

3. The adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam, as described in claim 1, is characterized in that: The width of the cam groove (61) on the grooved cam disk (6) is equal to the diameter of the roller (8).

4. The adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam, as described in claim 1, is characterized in that: A wind vane (11) is fixed to the lower end of the grooved cam disk (6), and the wind vane (11) is located below the wind turbine. The upper end of the support column (2) is formed with a connecting shaft (21), and the grooved cam disk (6) is connected to the connecting shaft (21) through a bearing.

5. The adaptive variable airfoil device for a vertical axis wind turbine based on the linkage of a wind vane and a cam, as described in claim 1, is characterized in that: The pitch angle of the trailing edge (51) is 2° to 4°.

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