Wind turbines and wind power generation equipment

Abstract

To provide a wind turbine capable of improving rotational energy conversion efficiency.SOLUTION: A wind turbine includes a shaft, a blade, and a support material. The wind turbine is rotatable about a center axis of the shaft. The blade has a blade main body portion extending along an axial direction as a direction of the center axis. The blade main body portion includes a front edge as a front-side end in a rotating direction of the wind turbine, and a rear edge as a rear-side end in the rotating direction in a cross-sectional view orthogonal to the axial direction. The support material connects the shaft and the blade main body portion by being orthogonal to the axial direction and extending along a radial direction passing through the center axis. The support material has a first part adjacent to the blade main body portion, and a second part adjacent to the first part at a side opposite to the blade main body portion. The support material has a rear end as a rear-side end in the rotating direction. In a blade chord direction as a direction of a blade chord line connecting the front edge and the rear edge, a position of the rear end of the first part approaches a position of the rear edge, as it approaches the blade main body portion.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a wind turbine and a wind power generating device. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2011-169292 (Patent Document 1) describes a vertical wind turbine for wind power generation. The vertical wind turbine described in Patent Document 1 has a rotor, blades (wings), and horizontal support arms (support members). The rotor is rotatable around a central axis. The wings have main parts extending along the direction of the rotor's central axis (axial direction). The support members connect the main parts of the blades to the rotor by extending along a direction perpendicular to the axial direction and passing through the rotor's central axis (radial direction). The support members are approximately fish-shaped in a cross section perpendicular to the radial direction.

[0003] Japanese Patent No. 5527783 (Patent Document 2) describes a rotor for wind power generation. The rotor described in Patent Document 1 has a rotating shaft, blades (wings), and a support base (support material). The rotating shaft is rotatable around a central axis. The wings extend along the direction of the central axis of the rotating shaft (axial direction). The support material connects the blades to the rotating shaft by extending along a direction (radial direction) that is perpendicular to the axial direction and passes through the central axis of the rotating shaft. The support material is streamlined in a cross section perpendicular to the radial direction. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-169292 [Patent Document 2] Patent No. 5527783 Summary of the Invention [Problem to be solved by the invention]

[0005] In the wind turbine described in Patent Document 1 and the rotor described in Patent Document 2, the cross-sectional shape of the support material perpendicular to the radial direction is generally fish-shaped or streamlined, thereby reducing the air resistance of the support material itself and improving rotational energy conversion efficiency. However, the wind turbine described in Patent Document 1 and the rotor described in Patent Document 2 do not focus on airflow turbulence at the connection between the support material and the blades. Therefore, the wind turbine described in Patent Document 1 and the rotor described in Patent Document 2 leave room for improvement in rotational energy conversion efficiency.

[0006] The present invention has been made in view of the above-mentioned problems of the prior art, and more specifically, to provide a wind turbine and a wind power generation device that can improve the efficiency of rotational energy conversion. [Means for solving the problem]

[0007] A wind turbine according to a first aspect of the present invention comprises a shaft, a blade, and a support member. The wind turbine is rotatable around the central axis of the shaft. The blade has a blade main body extending along the axial direction, which is the direction of the central axis. In a cross-sectional view perpendicular to the axial direction, the blade main body includes a leading edge, which is the end on the forward side in the direction of rotation of the wind turbine, and a trailing edge, which is the end on the rear side in the direction of rotation. The support member connects the shaft and the blade main body by extending along a radial direction perpendicular to the axial direction and passing through the central axis. The support member has a first portion adjacent to the blade main body and a second portion adjacent to the first portion from the side opposite the blade main body. The support member has a rear end, which is the end on the rear side in the direction of rotation. In the chord direction, which is the direction of the chord line connecting the leading edge and the trailing edge, the position of the rear end of the first portion approaches the position of the trailing edge as it approaches the blade main body.

[0008] In the wind turbine according to the first aspect of the present invention, the support material may have a first member that extends radially to connect the shaft and the blade main body, and a pair of plate-shaped second members that axially sandwich the end of the first member on the blade main body side.

[0009] In the wind turbine according to the first aspect of the present invention, the length of the first portion in the radial direction may be equal to or less than a chord length, which is the distance between the leading edge and the trailing edge in the chord direction.

[0010] In the wind turbine according to the first aspect of the present invention, the thickness of the first portion in the axial direction may be smaller than the thickness of the second portion in the axial direction.

[0011] A wind turbine according to a second aspect of the present invention comprises a shaft, blades, and a support. The wind turbine is rotatable around the central axis of the shaft. The blades have blade main bodies extending along the axial direction, which is the direction of the central axis. The support connects the shaft and the blade main bodies by extending along a radial direction that is perpendicular to the axial direction and passes through the central axis. The support has a first portion adjacent to the blade main body and a second portion adjacent to the first portion from the side opposite the blade main body. The thickness of the first portion in the axial direction is smaller than the thickness of the second portion in the axial direction.

[0012] In the wind turbine according to the second aspect of the present invention, the blade main body may include, in a cross section perpendicular to the axial direction, a leading edge that is the end on the forward side in the direction of rotation of the wind turbine and a trailing edge that is the end on the rear side in the direction of rotation. The length of the first portion in the radial direction may be equal to or less than a chord length that is the distance between the leading edge and the trailing edge in the chord direction, which is the direction of a chord line connecting the leading edge and the trailing edge.

[0013] A wind turbine generator according to the present invention includes the wind turbine according to the first or second aspect of the present invention, and a generator that generates electricity by rotation of the wind turbine about its central axis. [Effects of the Invention]

[0014] According to the wind turbine according to the first aspect of the present invention, the wind turbine according to the second aspect of the present invention, and the wind power generator according to the present invention, it is possible to improve the rotational energy conversion efficiency. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a front view of a wind turbine generator 100. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 2 is a cross-sectional view of the wind turbine generator 200. [Figure 4] FIG. 10 is a cross-sectional view of a wind turbine generator 100 according to a modified example. [Figure 5] FIG. 2 is a perspective view of a wind turbine generator 300. [Figure 6] FIG. 2 is a cross-sectional view of a wind turbine generator 300. [Figure 7] FIG. 4 is a cross-sectional view of a wind turbine generator 400. [Figure 8] FIG. 4 is an enlarged side view of the wind turbine generator 400. [Figure 9] FIG. 2 is a perspective view of a wind turbine generator 500. [Figure 10] FIG. 2 is a cross-sectional view of a wind turbine generator 500. DETAILED DESCRIPTION OF THE INVENTION

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the embodiments of the present invention will be described with reference to the accompanying drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and redundant description will not be repeated.

[0017] (First embodiment) A wind turbine generator according to a first embodiment (hereinafter referred to as a "wind turbine generator 100") will be described.

[0018] <Configuration of Wind Turbine Generator 100> The configuration of the wind turbine generator 100 will be described below.

[0019] Fig. 1 is a front view of a wind turbine generator 100. As shown in Fig. 1, the wind turbine generator 100 has a wind turbine 10 and a generator 20. The generator 20 generates electricity when the wind turbine 10 rotates around a central axis A, which will be described later.

[0020] Wind turbine 10 is a vertical axis wind turbine (upright wind turbine). Wind turbine 10 has a shaft 11, blades 12, and support members 13. The central axis of shaft 11 is referred to as central axis A. The direction of central axis A is referred to as the axial direction. The direction perpendicular to the axial direction and passing through central axis A is referred to as the radial direction. Wind turbine 10 is rotatable around central axis A.

[0021] The shaft 11 extends in the axial direction. The shaft 11 is rotatable around a central axis A. The wing 12 has a wing main body 12a, a wing tip inclined portion 12b, and a wing tip inclined portion 12c. The wing main body 12a extends along the axial direction. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. As shown in FIG. 2, the wing main body 12a is, for example, a lift-type wing when viewed in a cross section perpendicular to the axial direction.

[0022] In a cross-sectional view perpendicular to the axial direction, the blade main body 12a has a leading edge 12aa and a trailing edge 12ab. The leading edge 12aa is the end of the blade main body 12a that is on the forward side in the direction of rotation of the wind turbine 10 (indicated by the arrow in FIG. 2). The trailing edge 12ab is the end of the blade main body 12a that is on the rear side in the direction of rotation of the wind turbine 10. The possible line connecting the leading edge 12aa and the trailing edge 12ab is defined as the chord line 12ac. The direction of the chord line 12ac is defined as the chord direction.

[0023] As shown in Figure 1, the blade tip inclined portion 12b is connected to one axial end (upper end) of the blade main body 12a. The blade tip inclined portion 12b extends upward from the upper end of the blade main body 12a, sloping radially inward. The blade tip inclined portion 12c is connected to the other axial end (lower end) of the blade main body 12a. The blade tip inclined portion 12c extends downward from the lower end of the blade main body 12a, sloping radially inward.

[0024] The support material 13 extends in the radial direction. The support material 13 extends in the radial direction, thereby connecting the shaft 11 and the blade 12 (blade main body portion 12a). As shown in FIG. 2, the support material 13 has a front end 13a and a rear end 13b in a plan view (when viewed along the axial direction). The front end 13a is the end of the support material 13 that is on the front side in the rotation direction of the wind turbine 10. The rear end 13b is the end of the support material 13 that is on the rear side in the rotation direction of the wind turbine 10.

[0025] The support member 13 has a first portion 13c and a second portion 13d. The first portion 13c is the portion of the support member 13 adjacent to the wing main body portion 12a, and the second portion 13d is the portion of the support member 13 adjacent to the first portion 13c from the side opposite the wing main body portion 12a.

[0026] In the chord direction, the position of the trailing end 13b of the first portion 13c approaches the trailing edge 12ab as it approaches the blade main body 12a. From another perspective, the line indicating the position of the trailing end 13b of the first portion 13c forms an obtuse angle with the line indicating the position of the trailing end 13b of the second portion 13d. From yet another perspective, the width of the first portion 13c in the chord direction increases as it approaches the blade main body 12a.

[0027] The line indicating the position of the leading end 13a of the first portion 13c and the line indicating the position of the leading end 13a of the second portion 13d are, for example, collinear. The position of the trailing end 13b of the first portion 13c at the end on the blade main body 12a side preferably coincides with the position of the trailing edge 12ab. Furthermore, it is preferable that the position of the trailing end 13b of the first portion 13c does not protrude beyond the position of the trailing edge 12ab in the blade chord direction.

[0028] The length of the first portion 13c in the radial direction is preferably equal to or less than the length of the chord line 12ac (i.e., the chord length). The width of the second portion 13d in the chord direction is smaller than the width of the first portion 13c in the chord direction. However, at the boundary between the first portion 13c and the second portion 13d, the width of the second portion 13d in the chord direction is equal to the width of the first portion 13c in the chord direction.

[0029] <Effects of the wind power generation device 100> The effects of the wind turbine generator 100 will be explained below in comparison with a wind turbine generator according to a comparative example (hereinafter referred to as "wind turbine generator 200"). The configuration of the wind turbine generator 200 is the same as the configuration of the wind turbine generator 100, except for the details of the support member 13.

[0030] Fig. 3 is a cross-sectional view of the wind turbine generator 200. Fig. 3 shows a cross-section at a position corresponding to II-II in Fig. 1. As shown in Fig. 3, in the wind turbine generator 200, the support member 13 is not divided into a first portion 13c and a second portion 13d. That is, in the support member 13, the line indicating the position of the front end 13a is made up of a single straight line, and the line indicating the position of the rear end 13b is also made up of a single straight line. From another perspective, in the wind turbine generator 200, the width of the support member 13 in the chord direction is constant throughout the radial direction.

[0031] According to the findings of the present inventors, in wind turbine generator 200, airflow turbulence can occur at a position (the region indicated by the dotted line in Figure 3) rearward in the direction of rotation from the connection between support member 13 and blade main body 12a. This airflow turbulence interferes with the blade surface (i.e., the surface of blade main body 12a), inducing separation of the airflow flowing over the blade surface.

[0032] On the other hand, in the wind turbine generator 100, the position of the rear end 13b of the first portion 13c approaches the position of the trailing edge 12ab as it approaches the blade main body 12a in the blade chord direction, so that the support material 13 is also present in the region indicated by the dotted line in Figure 3. As a result, in the wind turbine generator 100, the position where turbulence in the airflow occurs moves further rearward in the direction of rotation, making it less likely for the turbulence to interfere with the blade surface. In this way, with the wind turbine generator 100, separation of the airflow flowing over the blade surface is less likely to be induced, improving the rotational energy conversion efficiency.

[0033] In wind turbine generator 100, rear end 13b of first portion 13c juts out toward trailing edge 12ab, which increases the weight of support material 13 and increases the centrifugal force acting on support material 13 when wind turbine 10 rotates, compared to wind turbine generator 200. If the radial length of first portion 13c is equal to or less than the chord length of blade main body 12a, it is possible to improve rotational energy conversion efficiency while suppressing the weight increase.

[0034] <Modification> Fig. 4 is a cross-sectional view of a wind turbine generator 100 according to a modified example. Fig. 4 shows a cross section taken along a line II-II in Fig. 1. As shown in Fig. 4, the rear end 13b of the first portion 13c may be curved.

[0035] (Second embodiment) A wind turbine generator according to a second embodiment (hereinafter referred to as "wind turbine generator 300") will be described. Here, differences from the wind turbine generator 100 will be mainly described, and overlapping descriptions will not be repeated.

[0036] The wind turbine generator 300 has a wind turbine 10 and a generator 20. The wind turbine 10 has a shaft 11, blades 12, and a support member 13. The support member 13 has a first portion 13c and a second portion 13d. In these respects, the configuration of the wind turbine generator 300 is common to the configuration of the wind turbine generator 100.

[0037] Fig. 5 is a perspective view of the wind turbine generator 300. Fig. 6 is a cross-sectional view of the wind turbine generator 300. Fig. 6 shows a cross-section at a position corresponding to II-II in Fig. 1. As shown in Figs. 5 and 6, the support member 13 is made up of a first member 14 and a pair of second members 15. In this respect, the configuration of the wind turbine generator 300 differs from the configuration of the wind turbine generator 100.

[0038] The first member 14 extends in the radial direction. This connects the shaft 11 and the blade 12 (blade main body portion 12a) via the first member 14. The pair of second members 15 sandwich the end of the first member 14 on the blade main body portion 12a side in the axial direction. The second members 15 are plate-shaped members. The pair of second members 15 and the end of the first member 14 sandwiched between the pair of second members 15 constitute the first portion 13c, and the portion of the first member 14 not sandwiched between the pair of second members 15 constitutes the second portion 13d.

[0039] Since the wind turbine generator 300 has the first portion 13c, separation of the airflow flowing over the blade surface is less likely to occur, as in the wind turbine generator 100, and as a result, rotational energy conversion efficiency can be improved. Note that in the above example, the first member 14 and the pair of second members 15 are separate members, but the same effect can be achieved by forming them into a single member with the same structure. Also, while the second member 15 is shown as a pair of separate members in FIG. 6, they may also be formed into a single structure by bending a single member.

[0040] (Third embodiment) A wind turbine generator according to a third embodiment (hereinafter referred to as "wind turbine generator 400") will be described. Here, differences from the wind turbine generator 100 will be mainly described, and overlapping descriptions will not be repeated.

[0041] <Configuration of wind turbine generator 400> The configuration of the wind turbine generator 400 will be described below.

[0042] The wind turbine generator 400 has a wind turbine 10 and a generator 20. The wind turbine 10 has a shaft 11, blades 12, and a support member 13. The support member 13 has a first portion 13c and a second portion 13d. In these respects, the configuration of the wind turbine generator 400 is common to the configuration of the wind turbine generator 100.

[0043] FIG. 7 is a cross-sectional view of the wind turbine generator 400. FIG. 7 shows a cross-section at a position corresponding to II-II in FIG. 1. FIG. 8 is an enlarged side view of the wind turbine generator 400. As shown in FIGS. 7 and 8, in the wind turbine generator 400, the rear end 13b of the first portion 13c does not protrude toward the trailing edge 12ab. That is, in the wind turbine generator 400, the width of the first portion 13c in the chord direction is constant throughout the radial direction. Furthermore, in the wind turbine generator 400, the axial thickness of the first portion 13c is smaller than the axial thickness of the second portion 13d. In these respects, the configuration of the wind turbine generator 400 differs from the configuration of the wind turbine generator 100.

[0044] In wind turbine generator 400, the width of first portion 13c in the chord direction is preferably smaller than the width of second portion 13d in the chord direction. Also, in wind turbine generator 400, the length of first portion 13c in the radial direction is preferably equal to or shorter than the chord length of blade main body 12a.

[0045] <Effects of the wind power generation device 400> The effects of the wind turbine generator 400 will be described below.

[0046] As the projected area of ​​the support material 13 when viewed from the side (the thickness of the support material 13 in the axial direction) increases, the turbulence of the airflow generated from the support material 13 increases. In the wind turbine generator 400, the portion of the support material 13 with a large projected area when viewed from the side (second portion 13d) is located away from the blade main body 12a, so the turbulence of the airflow generated by the support material 13 is less likely to interfere with the blade main body 12a.

[0047] Furthermore, in wind turbine generator 400, the portion of support material 13 with a small projected area when viewed from the side (first portion 13c) is adjacent to blade main body 12a, so that the rotational resistance of support material 13 in the portion of support material 13 where the peripheral speed is high can be reduced, and the turbulence of the airflow that occurs can be reduced compared to second portion 13d. Therefore, wind turbine generator 400 improves the rotational energy conversion efficiency.

[0048] In the wind power generation device 400, the cross-sectional area of ​​the first portion 13c is small, but by making the radial length of the first portion 13c equal to or less than the chord length of the blade main body portion 12a, it is possible to improve the rotational energy conversion efficiency while suppressing a decrease in the rigidity of the support material 13.

[0049] (Fourth embodiment) A wind turbine generator according to a fourth embodiment (hereinafter referred to as a "wind turbine generator 500") will be described. Here, differences from the wind turbine generator 100 will be mainly described, and overlapping descriptions will not be repeated.

[0050] The wind turbine generator 500 has a wind turbine 10 and a generator 20. The wind turbine 10 has a shaft 11, blades 12, and a support member 13. The support member 13 has a first portion 13c and a second portion 13d. In these respects, the configuration of the wind turbine generator 500 is common to the configuration of the wind turbine generator 100.

[0051] Fig. 9 is a perspective view of the wind turbine generator 500. Fig. 10 is a cross-sectional view of the wind turbine generator 500. Fig. 10 shows a cross section taken along the line II-II in Fig. 1. As shown in Figs. 9 and 10, the thickness of the first portion 13c in the axial direction is smaller than the thickness of the second portion 13d in the axial direction. In this respect, the configuration of the wind turbine generator 500 differs from the configuration of the wind turbine generator 100.

[0052] The configuration of the wind turbine generator 500 is a combination of the configurations of the wind turbine generator 100 and the wind turbine generator 400. Therefore, the wind turbine generator 500 can further improve the rotational energy conversion efficiency compared to the wind turbine generator 100 or the wind turbine generator 400.

[0053] Although the embodiments of the present invention have been described above, the above-described embodiments can be modified in various ways. Furthermore, the scope of the present invention is not limited to the above-described embodiments. The scope of the present invention is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. [Industrial Applicability]

[0054] The above-described embodiment is particularly advantageously applied to a vertical axis wind turbine and a wind power generation system having a vertical axis wind turbine. [Explanation of symbols]

[0055] 10 wind turbine, 11 shaft, 12 blade, 12a blade main body, 12aa leading edge, 12ab trailing edge, 12ac chord line, 12b, 12c wing tip slope, 13 support, 13a leading end, 13b trailing end, 13c first part, 13d second part, 14 first member, 15 second member, 20 generator, 100, 200, 300, 400, 500 wind power generation device, A central axis.

Claims

1. A windmill, a shaft, a wing, and a support; The wind turbine is rotatable around a central axis of the shaft, The blade has a blade main body portion extending along an axial direction that is the direction of the central axis, the blade main body includes, in a cross-sectional view perpendicular to the axial direction, a leading edge that is an end on a front side in a rotation direction of the wind turbine and a trailing edge that is an end on a rear side in the rotation direction, the support member extends along a radial direction perpendicular to the axial direction and passing through the central axis, thereby connecting the shaft and the blade main body portion; the support member has a first portion adjacent to the wing main body portion and a second portion adjacent to the first portion from the side opposite to the wing main body portion, the support member has a rear end that is a rear end in the rotation direction, In a chord direction, which is a direction of a chord line connecting the leading edge and the trailing edge, the position of the rear end of the first portion approaches the position of the trailing edge as it approaches the wing main body, a position of the trailing end of the first portion at the end of the blade body side coincides with a position of the trailing edge.

2. 2. The wind turbine according to claim 1, wherein the support material comprises a first member that extends in the radial direction to connect the shaft and the blade main body, and a pair of plate-shaped second members that sandwich an end of the first member on the blade main body side in the axial direction.

3. A wind turbine as described in claim 1, wherein the thickness of the first portion in the axial direction is smaller than the thickness of the second portion in the axial direction.

4. A wind turbine as described in any one of claims 1 to 3, wherein the length of the first part in the radial direction is less than or equal to the chord length, which is the distance between the leading edge and the trailing edge in the chord direction.

5. A windmill, a shaft, a wing, and a support; The wind turbine is rotatable around a central axis of the shaft, The blade has a blade main body portion extending along an axial direction that is the direction of the central axis, the support member extends along a radial direction perpendicular to the axial direction and passing through the central axis, thereby connecting the shaft and the blade main body portion; the support member has a first portion adjacent to the wing main body portion and a second portion adjacent to the first portion from the side opposite to the wing main body portion, a thickness of the first portion in the axial direction is smaller than a thickness of the second portion in the axial direction; the blade main body includes, in a cross-sectional view perpendicular to the axial direction, a leading edge that is an end on a front side in a rotation direction of the wind turbine and a trailing edge that is an end on a rear side in the rotation direction, the support member has a rear end that is a rear end in the rotation direction, a position of the trailing end of the first portion at the end of the blade body side coincides with a position of the trailing edge.

6. 6. The wind turbine according to claim 5, wherein a length of the first portion in the radial direction is equal to or less than a chord length that is a distance between the leading edge and the trailing edge in a chord direction that is a direction of a chord line connecting the leading edge and the trailing edge.

7. The wind turbine according to any one of claims 1 to 6; a generator that generates electricity by rotation of the wind turbine about the central axis.

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