KR20100014204A - Vertical axis type darrieus windmill - Google Patents

Abstract

PURPOSE: A vertical axis Darrieus windmill is provided to enable use in a wide wind speed range by a driving unit for assisting the drive or rotation of a primary rotary shaft at low wind speed. CONSTITUTION: A vertical axis Darrieus windmill includes a driving unit which assists the drive or rotation of a primary rotary shaft at low wind speed. The driving unit includes a cut part(7) which generates drag by wind on one inner side of a primary blade facing the primary rotary shaft(35) and a sub windmill which is coupled with the primary rotary shaft and generates torque by the drag at low wind speed and by lift at high wind speed.

Description

Vertical axis type Darrieus windmill}

The present invention relates to a Darius windmill, and more particularly, to a vertical axis-type Darius windmill that is capable of maneuvering itself in a low wind speed region.

In general, a windmill rotates a blade by natural wind, and converts it into electrical power by rotating a generator by increasing the speed by using a gear mechanism or the like.

This method is called wind power generation. Wind power generation windmills are represented by Dutch windmills. The horizontal windmills whose rotation axis is horizontal with respect to the wind and the vertical windmills whose rotation axis is perpendicular to the wind are known. .

Among these, the vertical axis windmill is known as a drag type that rotates the windmill by the drag generated on the blade, such as a paddle type or savonius type, and a lift type that rotates the windmill by the lifting force generated on the blade, such as the Darius type or the gyromill type. have.

That is, the former rotates the windmill by the drag difference by reducing the resistance of the blade toward the blow-up side, while the latter rotates the windmill by the lift force generated in the blade.

In the case of the electron (drag type) of the vertical axis type, when the circumferential speed ratio (blade air foil end speed / wind speed) is 1, a moment for rotating the windmill no longer occurs, and even if the wind speed rises, even more rotational speed may be obtained. And low power generation efficiency.

In the latter case (lift type), the aerodynamic characteristics of the windmill are improved and the windmill can be efficiently rotated at a circumferential speed ratio of 1 or more, but the aerodynamic characteristics of the windmill are deteriorated at a circumferential speed ratio of 1 or less, so that the moment of rotating the windmill becomes small. In addition, there is a drawback that the starting moment is small and the starting from the stop state becomes very difficult.

Therefore, an attempt was made to increase the maneuvering efficiency at low speed by combining the former drag type windmill with the latter lift type windmill.

Japanese Laid-Open Patent Publication No. 2003-314432 discloses a hybrid windmill.

The windmill is a structure in which the Savonius windmill, which is a drag type windmill, is integrally installed on the rotary shaft of the Darius windmill, which is a lift type windmill. to be.

However, in the conventional hybrid windmill as described above, the Savonius windmill drives the Darius windmill at low speed, but at high wind speed, the Darius windmill drives the Savonius windmill, so the rotational speed is reduced, and thus, at a high speed compared to a single Darius windmill. There is a problem that the power generation efficiency is lowered.

The present invention has been made to improve the above problems, and has a good aerodynamic characteristics in high wind speed, while using the advantages of Darius windmill with high power generation efficiency, it is possible to provide a Darius windmill that can generate power by itself in a low wind speed region. Its purpose is to.

Another object of the present invention is to provide a Darius windmill that can increase the power generation capacity, the rotation speed is not lower than the conventional Darius windmill in the high wind speed region.

In order to achieve the above object, the vertical axis Darius windmill of the present invention is a Darius windmill that rotates a first rotational shaft vertically formed by the lifting force generated in the first blade. And a maneuvering means for assisting.

The maneuvering means is characterized in that it comprises an ablation section cut off so that drag is generated by the wind on one side of the inward surface of the first blade facing the first rotary shaft.

The starting means is coupled to the first rotating shaft to generate a rotation moment by the drag force at low wind speed, characterized in that it is provided as an auxiliary windmill for generating a rotation moment by lift force at high wind speed.

The auxiliary windmill may include a plurality of zones formed radially on the outer circumferential surface of the first rotary shaft, and second blades fixed to the supports and rotating horizontally around the first rotary shaft, respectively.

The second blade is formed in a streamlined cross-sectional shape of the air foil, characterized in that provided on one side of the inward facing surface facing the first rotating shaft is cut off so that the drag is generated by the wind.

The auxiliary windmill is coupled to the first rotary shaft at low wind speeds and interlocked, and at high wind speeds, the secondary windmill is separated from the first rotary shaft and rotates independently of the first rotary shaft. And a plurality of supports formed radially on the outer circumferential surface, and second blades fixed to the supports and rotating horizontally around the second rotation shaft.

The first rotary shaft is installed coaxially inside the second rotary shaft is hollow inside, characterized in that the one-way clutch is coupled between the second rotary shaft and the first rotary shaft.

The auxiliary windmill includes supporters formed on an outer circumferential surface of the first rotation shaft, and a second blade fixed to the supports to rotate horizontally around the first rotation shaft and spirally formed with respect to the first rotation shaft. It is done.

The starting means is further coupled to the first rotating shaft to generate a rotation moment by the drag force at low wind speed, and at a high wind speed further comprises an auxiliary windmill for generating a rotation moment by lift force.

As described above, according to the vertical axis Darius windmill of the present invention, in the low wind speed region, it is possible to start and rotate by itself due to the drag generated on the blades, and thus the power generation is possible at low wind speeds.

In addition, the rotation moment can be generated in any wind direction and wind speed, so it is easy to maneuver even in the city where the wind speed is very low or the fluctuation of the wind direction provides the advantage of power generation in a wide range of wind speed range.

In addition, the blades of the auxiliary windmill can generate high rotational moments by lifting force in the high wind speed region, thereby enabling high rotation, so that the advantages of Darius windmills having excellent aerodynamic characteristics in the high wind speed region can be used as they are.

Along with this, the auxiliary shaft may be provided with a separate rotary shaft, but may be configured to interlock with each other at a low wind speed, and may be configured to be separated at a high wind speed. In this case, power generation capacity may be greatly increased by independently connecting the power generation units to each rotary shaft.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the Darius windmill according to an embodiment of the present invention.

1 is a perspective view showing a Darius windmill according to an embodiment of the present invention, Figure 2 is a perspective view showing a Darius windmill according to another embodiment of the present invention, Figure 3 is a pressure distribution around the second blade applied to Figure 2 4 is a view illustrating a rotation operation of the second blade applied to FIG. 2, FIG. 5 is a cross-sectional view showing a Darius windmill according to another embodiment of the present invention, and FIG. 6 is applied to FIG. 5. 7 is a cross-sectional view illustrating a structure of a one-way clutch, and FIG. 7 is a cross-sectional view showing a Darius windmill according to another embodiment of the present invention, and FIGS. 8 to 9 are perspective views illustrating a Darius windmill according to still another embodiment of the present invention. .

The biggest feature of the Darius windmill of the present invention is to have a maneuvering means to enable self-maneuvering at low wind speeds. In the present invention, the maneuvering means is further provided by an auxiliary windmill or implemented by improving the structure of the blade of the conventional Darius windmill.

First, the Darius windmill of the present invention having an auxiliary windmill as a starting means will be described with reference to FIGS. 2 to 4. The present invention has a hybrid windmill structure in which a first windmill that is a Darius windmill is coupled to a second windmill that is an auxiliary windmill.

The first windmill uses a conventional Darius windmill. An example of the illustrated first windmill is composed of a first rotary shaft 35 formed perpendicular to the wind and two first blades 31 connected to the first rotary shaft 35. The upper end of the first blade 31 is fixed to the disk-shaped bracket 39 fixed to the upper end of the first rotary shaft 35, and the lower end is fixed to the lower outer peripheral surface of the first rotary shaft 35. The first blade 31 may be provided in three or more pieces.

The first blade 31 has an arc-shaped shape as a whole, and is formed in a streamlined air foil shape to rotate the first rotating shaft 35 by lifting force. The first blade 31 applied to the first windmill can be rotated at a high rotational speed by improving the aerodynamic characteristics of the windmill in a high wind speed region in which the main speed ratio (air foil end speed / wind speed of the blade) becomes one or more. In addition, since the first rotation shaft 35 is vertical, it has an advantage of not being affected by the wind direction.

And although not shown, the first windmill is capable of generating wind power when the lower end of the first rotary shaft 35 is connected to the power generation unit. However, the lift type first blade 31 of the first windmill has a problem in that it cannot generate power in the region of low wind speed because it can not start by itself at a speed ratio of 1 or less.

Therefore, in this invention, the 2nd windmill is provided as a starting means of a 1st windmill. The second windmill generates the rotation moment by the drag force at low wind speed, and generates the rotation moment by the lift force at high wind speed. The second windmill starts the first rotary shaft 35 by drag at low wind speed and rotates high by lift force at high wind speed, so that the second windmill hardly loads the first blade 31 which rotates at high wind speed at high speed. The advantages of the first windmill with good aerodynamic characteristics can be used as it is in the area.

In the conventional hybrid windmill combined with the Darius windmill and the Savonius windmill, since the Darius windmill rotates the Savonius windmill in the high wind speed region, generation loss due to the deceleration of the Darius windmill occurs, but the present invention rotates by lift Power generation loss at high wind speed is hardly generated by the second windmill.

As a specific example of the second windmill, a plurality of supports 27 are radially orthogonal to the first and second rotation shafts 35 on the outer circumferential surfaces of the upper and lower portions of the first rotation shaft 35 within the rotation region of the first blade 31. It is formed to extend. The second blade 20 is installed at the ends of the four supporters 27 in the circumferential direction of the same radius in the plane orthogonal to the first rotation shaft 35.

The second blade 20 is formed by pressing a thin plate-shaped material made of a metal material such as aluminum alloy, or extrusion molding using a resin.

The second blade 20 is formed in a streamlined air foil type used in an airplane whose cross section is represented by a four magnetic field air foil type, a RAF air foil type, a gettingen air foil type, etc., and faces the first rotating shaft 35. An incision 25 is formed on the inwardly facing surface B. The cutout portion 25 is formed by cutting over the trailing edge b at a position between 35% and 45% from the leading edge a. As a result, the second blade 20 is formed into an air foil type having a high lift coefficient with a low Reynolds number.

Around the second blade 20 having the above structure, a pressure distribution is formed against the wind from the front (arrow C direction) as shown in FIG. That is, in the pressure distribution of the air foil type used in the second blade 20, a pressure higher than the outside air pressure is distributed in the front portion (wind blowing direction) of the inner surface of the second blade 20, and in the rear portion, The pressure is about the same as the outside air pressure, and since the flow velocity is accelerated by the air foil shape on the outward surface, the pressure decreases to form a negative pressure. Therefore, even if the cutout part 25 is provided in the back of the inward face of the 2nd blade 20, the aerodynamic characteristic of an air foil is small.

As shown in FIG. 4, when the second blade 20 receives wind from the front (arrow C direction), the second blade 20 generates a lift force, and thus, the second blade 20 receives the second blade by the rotational direction component of the lift force generated in the second blade 20. The blade 20 rotates clockwise.

In addition, when the second blade 20 receives wind from the rear side (in the direction of arrow D in the drawing) in the low wind speed region as in the start-up, the second blade 20 is cut by the cutout portion 25 of the second blade 20. Large air resistance occurs at 20. As a result, a rotation moment is generated in the second blade 20 by the Savonius windmill effect, that is, air resistance, thereby generating starting torque of the windmill.

As a result, since the ablation part 25 is formed in the inward surface of the 2nd blade | wing 20, the rotation moment is reduced by the air resistance in the low wind speed area | region of 1 or less with respect to the wind from the D arrow direction of FIG. Is generated.

Then, the moment is applied to the rotational direction component force of the lifting force generated in the second blade 20 which receives the wind from the arrow C direction of FIG. 4, and rotates. It is rotated by the generated lift. That is, since the second blade 20 is formed in an air foil type having a high lift coefficient with a low Reynolds number, the second blade 20 can be rotated even at a low wind speed of 1 m / sec or less, thereby efficiently generating power. . In addition, since the second blade 20 uses a lightweight member such as an aluminum alloy, the weight of the second blade 20 as a whole becomes small, thereby reducing the load due to the centrifugal force generated in the second blade 20.

In the above embodiment, since the second blade type having a high lift coefficient is used with a low Reynolds number, air resistance and lift force due to wind are generated in the second blade 20, and the second blade 20 is driven by these forces. Rotate Therefore, in any wind direction and wind speed, the second blade 20 can generate a rotation moment necessary for power generation. As a result, the second blade 20 can be rotated over a wide range of wind speeds.

In addition, since the second blades 20 are arranged around the first rotating shaft 35, the second blades can be efficiently rotated against the wind from all directions. Since the first rotary shaft 35 can be rotated to generate power, the first rotary shaft 35 can be installed in a city center having high variability in wind direction.

In the above embodiment, four second blades 20 are arranged, but not limited thereto, and three or less blades or five or more blades may be used, and the same effects and effects as those of the above embodiments may be achieved. .

Although not shown, it is also possible to attach the tip cover for reducing air resistance to the second blade 20 at both ends, or to attach winglets for reducing the inductive resistance of the second blade 20 as necessary.

As described above, the hybrid windmill 10 of the present invention is started by the second blade 20 at low wind speed so that the first rotation shaft 35 rotates. When the wind speed increases and reaches the high wind speed region, high rotation is possible by the first blade 31 which is lift type. In this case, since the second blade 20 can also be rotated by lift, high load is hardly applied to the first blade 31 which rotates at high speed in the high wind speed region, so that power generation efficiency is not significantly reduced.

On the other hand, when the second blade 20 is initially started in the stop state and rotates at a predetermined speed or more, the inwardly facing surface B becomes lower than a predetermined speed in order to reduce the resistance of the air due to the vortex generated in the ablation section 25. It may have a structure in which the cut end of the) is in close contact with the outward surface (A) side.

This forms a second blade 20 having the shape shown above by using two sheets of plate material, the two sheets of plate material are connected to be rotatable with each other at the leading edge (a) of the second blade (20). And the front end of the support 27 passes through the inward surface (B) of the second blade 20 is fixedly connected to the outward surface (A). In this case, the diameter of the through hole of the inward surface B through which the support penetrates is made larger than the diameter of the support 27 so that the inward surface moves along the longitudinal direction of the support, and can rotate at an angle with respect to the outward surface A. Do it. And the support between the inward surface (B) and the outward surface (A) is provided with springs connected at both ends to the outward surface (A) and the inward surface (B) respectively to elastically bias the inward surface (B) in the direction of the rotation axis. In this case, the elastic force of the spring is set to be smaller than the centrifugal force acting on the inward surface when the second blade 20 rotates at a predetermined speed or more. Therefore, when the second blade 20 is stopped or below a certain speed, the tip of the inwardly facing surface B is spaced apart from the outwardly facing surface A by a predetermined distance, but the centrifugal force is higher than the elastic force of the spring acting on the inwardly facing surface B above a certain speed. This becomes larger and the tip of the inwardly facing surface B is in close contact with the outwardly facing surface A, which can greatly reduce the resistance of air due to vortices.

On the other hand, while the second blade has been described in the vertically formed structure, as shown in Figure 8, the second blade 105 may be formed spirally with respect to the first rotating shaft (35). The spiral second blade 105 is fixed to the supports 107 formed horizontally on the outer circumferential surface of the first rotation shaft 35.

Since the aerodynamic characteristics acting on the blade 105 acts along the spiral of the second blade 105, the second blade 105 can be easily rotated even in various wind directions, thereby improving the maneuverability of the first rotating shaft 35. .

5 and 6, in another embodiment of the present invention, the second windmill is provided with a second rotating shaft 45 to which the second blade 20 is coupled coaxially with the first rotating shaft. The second rotary shaft 45 rotates in association with the first rotary shaft 35 at low wind speeds, and is separated from the first rotary shaft 35 at high wind speeds to rotate independently of the first rotary shaft.

The first rotary shaft 35 connected to the lower portion of the power generation unit 93 is vertically formed, and the first blade 31 of the lift type is installed on the first rotary shaft 35. In addition, a second rotating shaft 45 surrounding the outer circumferential surface of the first rotating shaft 35 positioned below the rotating region of the first blade 31 is provided coaxially with the first rotating shaft 35. In this case, the second rotating shaft 45 is supported and installed to be rotatable in the housing 91. The first rotary shaft 35 is inserted to pass through the center of the second rotary shaft 45 having a hollow inside, and the inner circumferential surface of the second rotary shaft 45 is installed to be spaced apart from the outer circumferential surface of the first rotary shaft 35.

And the one-way clutch 80 that can be rotated in only one direction is coupled between the inner circumferential surface of the second rotary shaft 45 and the outer circumferential surface of the first rotary shaft 35. The inner rotating body 83 of the one-way clutch 80 is coupled to the first rotating shaft 35, and the outer rotating body 81 is coupled to the second rotating shaft 45.

Therefore, when the second rotation shaft 45 rotates clockwise due to the drag generated in the second blade 20 in the low wind speed region, the roller 87 supported by the spring 85 moves to the opposite side of the spring and rotates outward. The whole 81 is pressed while contacting the inner rotor 83. Therefore, the first rotary shaft 35 rotates in a state coupled with the second rotary shaft 45.

When the wind speed increases to reach the high wind speed region, the spring of the one-way clutch is at a time when the rotation speed of the first rotation shaft 35 is increased than the rotation speed of the second rotation shaft 45 by the high speed rotation of the first blade 31. As shown in FIG. 6, the outer rotating body 81 is spaced apart from the inner rotating body 83 as the roller 87 supported by the roller 87 moves toward the spring 85 so that the first rotating shaft 35 is the second rotating shaft 45. The first rotary shaft rotates independently from

In addition, when the rotational speed decreases, the first rotational shaft rotates in combination with the second rotational shaft by the action of the one-way clutch 80.

As described above, when the rotation speeds of the first and second rotation shafts are different from each other in the high wind speed region, in particular, when the rotation speed of the first rotation shaft 35 is earlier than the second rotation shaft 45, the first rotation shaft 35 The load for rotating the two rotary shafts 45 together disappears, so that the power generation efficiency of the first rotary shaft 35 is not lowered.

As another embodiment of the present invention, as shown in FIG. 7, the second blade 20 is installed in the rotation region of the first blade 31. In this case, the first rotating shaft 35 to which the lower end of the first blade 31 is fixed is rotatably supported by the housing 91 and installed vertically. In addition, the second rotating shaft 45 to which the second blade 20 is coupled is installed coaxially through the center of the first rotating shaft 35 having a hollow inside, and the second rotating shaft 45 is the first rotating shaft 35. It is formed to extend a predetermined length from both ends of the).

Power generation units 95 and 97 are connected to lower portions of the first rotation shaft 35 and the second rotation shaft 45, respectively, and the second blade 20 fixed to the supports 27 is connected to the second rotation shaft 45. Is installed. And the upper end of the second rotating shaft 45 is provided with a disk-shaped rotating bracket 75 that can be rotated independently of the second rotating shaft 45, the first blade 31 is fixed to the rotating bracket 75, the upper end The lower end is fixed to the outer circumferential surface of the first rotary shaft 35. The one-way clutch 70 is coupled to the first and second rotation shafts 35 and 45.

When the hybrid windmill reaches the high wind speed region, the first rotation shaft 35 is separated from the second rotation shaft 45 to generate power while independently rotating. In addition, since the second rotary shaft 45 is also connected to a separate power generation unit 97, the present invention is the first rotary shaft 35 and the second rotary shaft 45 at high wind speed, each independently responsible for power generation capacity. Can greatly improve.

1 shows a Darius windmill according to another embodiment of the present invention. Referring to Figure 1, the present invention is characterized in that the conventional Darius wing for improving the magnetic force in the low wind speed region.

Both ends of the first blade 5 are fixed to the upper and lower supporters 1 and 3 fixed to the upper and lower portions of the outer circumferential surface of the first rotating shaft 35 formed vertically. In addition to the first blade 5, three or four pieces may be installed. The cross section of the first blade 5 has a streamlined air foil shape, and an ablation portion 7 is formed on an inward surface facing the first rotation shaft 35. Since the cutout 7 has the same operation and effect as the cutout of the second blade illustrated in FIG. 2, detailed description thereof will be omitted.

In the first blade 5 having the above structure, a large air resistance is generated by the cutout portion 7 in the low wind speed region. The rotational moment is generated on the first blade 5 by the air resistance, and the starting torque of the windmill is generated to start by itself.

9, the auxiliary windmill shown in FIG. 2 may be coupled to the first rotation shaft 35.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent embodiments thereof are possible.

Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

1 is a perspective view showing a Darius windmill according to an embodiment of the present invention,

2 is a perspective view showing a Darius windmill according to another embodiment of the present invention;

3 is a diagram showing a pressure distribution around the second blade applied to FIG.

4 is a view showing a rotation operation of the second blade applied to FIG.

5 is a cross-sectional view showing a Darius windmill according to another embodiment of the present invention;

6 is a cross-sectional view showing the structure of a one-way clutch applied to FIG.

7 is a cross-sectional view showing a Darius windmill according to another embodiment of the present invention;

8 to 9 are perspective views showing a Darius windmill according to another embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

20: Second Blade 27: Support

31: first blade 35: first rotating shaft

45: second rotary shaft 80: one-way clutch

Claims (9)

In the Darius windmill for rotating the first rotating shaft formed vertically by the lifting force generated in the first blade, A vertical axis Darius windmill, characterized in that it comprises a starting means for assisting the starting or rotation of the first rotary shaft at low wind speed. The vertical axis type Darius windmill according to claim 1, wherein the maneuvering means has a cut-out portion that is cut off so that drag is generated by wind on one side of the inward surface of the first blade facing the first rotating shaft. The vertical axis type Darius according to claim 1, wherein the maneuvering means has an auxiliary windmill coupled to the first rotational shaft to generate a rotation moment by drag at low wind speed and a rotation moment by lift force at high wind speed. windmill. The auxiliary windmill according to claim 3, wherein the auxiliary windmill comprises a plurality of supports formed radially on the outer circumferential surface of the first rotation shaft, and a second blade fixed to the supports and rotating horizontally around the first rotation shaft, respectively. Featuring a vertical Darius windmill. The vertical shaft of claim 4, wherein the second blade has a cross section formed in a streamlined shape of an airfoil, and one side of the inward surface facing the first rotation shaft includes a cut-off portion generated to generate drag by wind. Darius windmill. 4. The secondary windmill of claim 3, wherein the auxiliary windmill is coupled to the first rotary shaft at low wind speeds and interlocks. The secondary windmill is coupled to the first rotary shaft at high wind speeds, and is coupled to the first rotary shaft to rotate independently of the first rotary shaft. And a plurality of supports formed radially on the outer circumferential surface of the second rotary shaft, and a second blade fixed to the supports and rotating horizontally around the second rotary shaft, respectively. The vertical shaft of claim 6, wherein the first rotary shaft is installed coaxially in the second rotary shaft, and a one-way clutch is coupled between the second rotary shaft and the first rotary shaft. Darius windmill. According to claim 3, The auxiliary windmill is a support formed on the outer circumferential surface of the first rotary shaft, and the second fixed to the support to rotate around the first rotary shaft horizontally and formed spirally with respect to the first rotary shaft Darius windmill vertical axis characterized in that it comprises a blade. The vertical shaft type of claim 2, wherein the maneuvering means is further provided with an auxiliary windmill coupled to the first rotational shaft to generate a rotation moment by drag at low wind speed and a rotation moment by lift force at high wind speed. Darius windmill.

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