Drag-type wind turbines and wind power generation systems

Abstract

To provide a drag-type wind turbine with reduced costs. [Solution] The drag-type wind turbine comprises a power generation unit having blades, a first plate connected to the upper end of the blades, a second plate connected to the lower end of the blades, a generator, and a first shaft connected to the generator; a connecting member fixed to one of the first plate and the second plate and having a first hole into which the first shaft of the power generation unit is fitted; a second shaft arranged along the central axis of the drag-type wind turbine; and a holding member for holding the second shaft. Each of the first plate and the second plate has a main body that rotates with respect to the central axis of the drag-type wind turbine and a through hole positioned to coincide with the central axis. The second shaft is inserted through the respective through holes of the first plate and the second plate while being held by the holding member. As the first plate and the second plate rotate, the first shaft of the power generation unit rotates, while the second shaft 50 held by the holding member does not rotate.

Description

Technical Field

[0001] The present disclosure relates to a drag-type windmill and a wind power generation system.

Background Art

[0002] Patent Document 1 discloses a wind power generator including a main shaft, a bearing rotatably attached to the main shaft via a bearing, a rotary blade mechanism in which a rotary shaft to which blades for receiving power are attached is fixed coaxially with the main shaft above the bearing, and a generator unit. The wind power generator disclosed in Patent Document 1 includes at least two bearings each attached to the main shaft via a different bearing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the wind power generator disclosed in Patent Document 1, the structure for rotatably supporting the main shaft is complicated, which may lead to an increase in cost.

[0005] The disclosed technology aims to reduce the cost of the drag-type windmill.

Means for Solving the Problems

[0006] The drag wind turbine according to this disclosure is a vertical-axis drag wind turbine and comprises a power generation unit having blades, a first plate connected to the upper end of the blades, a second plate connected to the lower end of the blades, a generator, and a first shaft connected to the generator; a connecting member fixed to one of the first plate and the second plate and having a first hole into which the first shaft of the power generation unit is fitted; a second shaft arranged along the central axis of the drag wind turbine; and a holding member for holding the second shaft, wherein each of the first plate and the second plate has a main body that rotates with respect to the central axis of the drag wind turbine and a through hole positioned to coincide with the central axis, and the second shaft is inserted through the respective through holes of the first plate and the second plate while being held by the holding member, and the first shaft of the power generation unit rotates in accordance with the rotation of the first plate and the second plate, while the second shaft held by the holding member does not rotate.

[0007] The wind power generation system according to this disclosure is a wind power generation system comprising a vertical-axis drag wind turbine, the drag wind turbine comprising: a power generation unit having blades, a first plate connected to the upper end of the blades, a second plate connected to the lower end of the blades, a generator, and a first shaft connected to the generator; a connecting member fixed to one of the first plate and the second plate and having a first hole into which the first shaft of the power generation unit is fitted; a second shaft arranged along the central axis of the drag wind turbine; and a holding member for holding the second shaft, wherein each of the first plate and the second plate has a main body that rotates with respect to the central axis of the drag wind turbine and a through hole positioned to coincide with the central axis, the second shaft is inserted through the respective through holes of the first plate and the second plate while being held by the holding member, and the first shaft of the power generation unit rotates in accordance with the rotation of the first plate and the second plate, while the second shaft held by the holding member does not rotate. [Effects of the Invention]

[0008] According to the disclosed technology, the cost of drag-type wind turbines can be reduced. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic front view showing a drag-type wind turbine according to the first embodiment. [Figure 2] This is a longitudinal cross-sectional view showing a simulated drag-type wind turbine according to the first embodiment. [Figure 3] This is a schematic plan view showing the blades of a drag-type wind turbine according to the first embodiment. [Figure 4] This is a longitudinal cross-sectional view of the first flat plate provided in the drag-type wind turbine according to the first embodiment. [Figure 5] This is a longitudinal cross-sectional view of the second flat plate of the drag-type wind turbine according to the first embodiment. [Figure 6] This is a longitudinal cross-sectional view of the third flat plate of the drag-type wind turbine according to the first embodiment. [Figure 7] This is a schematic longitudinal cross-sectional view showing the power generation section of a drag-type wind turbine according to the first embodiment. [Figure 8] This is a schematic perspective view showing the power generation section of a drag-type wind turbine according to the first embodiment. [Figure 9] This is a perspective view showing an example of the connection configuration between the second flat plate and the connecting member of a drag-type wind turbine according to the first embodiment. [Figure 10] This is a longitudinal cross-sectional view of a connecting member provided in a drag-type wind turbine according to the first embodiment. [Figure 11] This is a longitudinal cross-sectional view showing an example of a holding member provided in a drag-type wind turbine according to the first embodiment. [Figure 12] This is a longitudinal cross-sectional view showing another example of a retaining member provided in a drag-type wind turbine according to the first embodiment. [Figure 13] This is a schematic block diagram showing the overall configuration of the wind power generation system according to the second embodiment. [Modes for carrying out the invention]

[0010] Hereinafter, embodiments for implementing the invention will be described with reference to the drawings. In each drawing, the same reference numerals are assigned to the same constituent parts, and duplicate descriptions are omitted as appropriate. In the drawings, as a direction expression, there may be cases where the X-axis, Y-axis, and Z-axis orthogonal to each other are shown. Also, in the X-axis direction, the side where the arrow points is referred to as the +X side, and the side opposite to the arrow is referred to as the -X side. In the Y-axis direction, the side where the arrow points is referred to as the +Y side, and the side opposite to the arrow is referred to as the -Y side. In the Z-axis direction, the side where the arrow points is referred to as the +Z side, and the side opposite to the arrow is referred to as the -Z side.

[0011] [First Embodiment] <Overall Configuration> Referring to FIGS. 1 to 6, an example of the configuration of the drag-type windmill 10 according to the first embodiment will be described. FIG. 1 is a front view schematically showing the drag-type windmill 10 according to the first embodiment. FIG. 2 is a longitudinal sectional view schematically showing the drag-type windmill 10 according to the first embodiment. FIG. 3 is a plan view schematically showing the blade 211 included in the drag-type windmill 10 according to the first embodiment. FIG. 4 is a longitudinal sectional view of the first flat plate 212a included in the drag-type windmill 10 according to the first embodiment. FIG. 5 is a longitudinal sectional view of the second flat plate 212b included in the drag-type windmill according to the first embodiment. FIG. 6 is a longitudinal sectional view of the third flat plate 212c included in the drag-type windmill according to the first embodiment.

[0012] As shown in FIGS. 1 and 2, the drag-type windmill 10 is a vertical-axis type and rotates by the drag force when the wind blows against the blade 211. Also, the drag-type windmill 10 may be a hybrid-type windmill that further includes a mechanism that rotates by the lift force when the wind blows against the blade 211. That is, "drag-type" in this specification may include at least a part of a mechanism that rotates by the drag force when the wind blows against the blade 211.

[0013] Examples of the types of the drag-type windmill 10 include the Savonius type, the cross-flow type, and the Bach type. In the example shown in FIG. 1, the drag-type windmill 10 is a Bach-type windmill. However, the drag-type windmill 10 may be a vertical-axis drag-type windmill other than these.

[0014] As shown in FIGS. 1 and 2, the drag-type wind turbine 10 includes a blade 211, a first flat plate 212a, a second flat plate 212b, a power generation unit 30, a connecting member 40, a shaft 50, and a holding member 60. The drag-type wind turbine 10 may further include other components such as a pedestal 70. When explaining a plurality of flat plates including the first flat plate 212a and the second flat plate 212b without distinction, these are collectively referred to as "flat plate 212" hereinafter.

[0015] The shaft 50 is disposed along the central axis of the drag-type wind turbine 10. In the example shown in FIGS. 1 and 2, the central axis extends along the Z-axis direction. For convenience of explanation, the shaft 50 is hereinafter referred to as the "second shaft 50". The holding member 60 holds the second shaft 50 in a state of being connected to the pedestal 70. The pedestal 70 is connected to the power generation unit 30 and the holding member 60, respectively.

[0016] The second shaft 50 is inserted into through holes (through holes such as the first through hole 222 and the second through hole 232 described later) of the flat plates 212 such as the first flat plate 212a and the second flat plate 212b while being held by the holding member 60. Since the second shaft 50 is fixed while being held by the holding member 60, the second shaft 50 does not rotate even when the first flat plate 212a and the second flat plate 212b rotate. In the example shown in FIGS. 4 and 5, the second shaft 50 is inserted into the inner ring 223a of a bearing (first bearing) 223 described later that the first flat plate 212a has, and the inner ring 243a of a bearing (second bearing) 233 described later that the second flat plate 212b has. The first flat plate 212a and the second flat plate 212b are separated while being supported by the first bearing 223 and the second bearing 233, respectively. The blade 211 is disposed in the space between the first flat plate 212a and the second flat plate 212b and is disposed so as to be sandwiched between the first flat plate 212a and the second flat plate 212b. On the other hand, the second flat plate 212b and the power generation unit 30 are connected via the connecting member 40. That is, by connecting the second flat plate 212b and the power generation unit 30 via the connecting member 40, the shaft 32 (first shaft 32) connected to the generator 31 of the power generation unit 30 can be rotated with respect to the central axis of the drag-type wind turbine 10 by the rotation of the first flat plate 212a and the second flat plate 212b with respect to the central axis of the drag-type wind turbine 10.

[0017] <Blade 211, flat plate 212> In the examples shown in Figures 1 and 2, two blades 211a and 211b are positioned between the first plate 212a and the second plate 212b. The two blades 211a and 211b are fixed to the first plate 212a and the second plate 212b. Each of the first plate 212a and the second plate 212b rotates with respect to the central axis of the drag-type wind turbine 10. The two blades 211a and 211b are positioned between the first plate 212a and the second plate 212b. The blades 211a and 211b, along with the first plate 212a and the second plate 212b, constitute a blade stage 21a. The number of blades 211 in the blade stage 21a is not limited to two. The number of blades 211 included in the blade stage 21a may be three or more.

[0018] In the examples shown in Figures 1 and 2, the drag-type wind turbine 10 is equipped with two stages of blades 21, consisting of vertically connected blade stages 21a and 21b. However, the number of stages of blades 21 equipped with the drag-type wind turbine 10 may be one or three or more. Blade stage 21b, like blade stage 21a, is equipped with blades 211c, 211d, a third plate 212c, and a first plate 212a. The third plate 212c and the first plate 212a each rotate with respect to the central axis of the drag-type wind turbine 10. The number of blades 211 equipped with blade stage 21b may be three or more.

[0019] Blade stage 21a and blade stage 21b share the first flat plate 212a. However, blade stage 21a and blade stage 21b do not necessarily have to share the first flat plate 212a. That is, blade stage 21b may have another flat plate 212 instead of the first flat plate 212a.

[0020] As shown in Figures 3(a) and 3(b), in the blade stage 21a, the blades 211a and 211b are arranged point-symmetrically with respect to the central axis (second shaft 50) of the drag wind turbine 10 in a plan view. Even when the drag wind turbine 10 is a different type of wind turbine than the Bach type, it is preferable that the multiple blades 211 of the blade stage 21a are arranged point-symmetrically with respect to the central axis of the drag wind turbine 10.

[0021] As shown in Figures 3(a) and 3(b), the blades 211a and 211b are arranged facing each other with the central axis of the drag-type wind turbine 10 in between. Blade 211a is positioned at a distance from blade 211b. A portion of the second shaft 50 is positioned in the space between blades 211a and 211b. As shown in Figure 3, each of the blades 211a and 211b has a first portion 2111 and a second portion 2112. Each of the blades 211a and 211b may further have other components different from the first portion 2111 and the second portion 2112. Depending on the wind direction and / or the rotation angle of the blade 211, either the front and back surfaces, or both, of the first portion 2111 and the second portion 2112 become the wind-receiving surfaces.

[0022] The first part 2111 extends outward from the vicinity of the central axis of the drag-type wind turbine 10 in a plan view. The first part 2111 may extend in a straight line in a plan view. Also, the first part 2111 has a substantially rectangular shape in a front view. The first part 2111 extends between the lower surface of the first plate 212a and the upper surface of the second plate 212b. However, the configuration of the first part 2111 is not limited thereto.

[0023] In a plan view, the second part 2112 curves in an arc from the outer end of the first part 2111. The outer end of the second part 2112 is located inside or overlaps with the outer edge C of the operating region through which the plate 212 passes when it rotates with respect to the central axis of the drag wind turbine 10. As shown in Figure 3(a), the outer edge C has a circular shape in a plan view. Here, the circle corresponding to the outer edge C shown in Figure 3 is a virtual circle obtained by projecting the operating region through which the plate 212 passes when it rotates with respect to the central axis of the drag wind turbine 10 onto a horizontal plane perpendicular to the central axis of the drag wind turbine 10. In the example shown in Figure 3, the virtual circle corresponding to the outer edge C overlaps with the first plate 212a and the second plate 212b, respectively, in a plan view. The second part 2112, like the first part 2111, extends between the lower surface of the first plate 212a and the upper surface of the second plate 212b.

[0024] As shown in Figure 4, the first flat plate 212a has a main body (first main body) 221, a through hole (first through hole) 222, and a bearing (first bearing) 223. The first main body 221 has a substantially disc shape that rotates with respect to the central axis of the drag-type wind turbine 10. That is, the first main body 221 has a substantially circular shape in plan view. However, the first main body 221 may have a shape other than substantially circular, such as a substantially ellipse, in plan view.

[0025] The first through-hole 222 is positioned to coincide with the central axis of the drag-type wind turbine 10. The first through-hole 222 is defined by the inner surface of the first main body 221. The second shaft 50 is located inside the first through-hole 222. In plan view, the first through-hole 222 has a substantially circular shape. However, in plan view, the first through-hole 222 may have a shape other than substantially circular, such as a substantially elliptical shape.

[0026] The first bearing 223 is attached to the first main body 221. The first bearing 223 supports the first main body 221. In the example shown in Figure 4, the first bearing 223 is located on the upper side of the first main body 221. However, the first bearing 223 may also be located on the lower side of the first main body 221.

[0027] In the example shown in Figure 4, the first bearing 223 is a rolling bearing. The first bearing 223 has an inner ring 223a, an outer ring 223b, and rolling elements 223c. The inner ring 223a is mounted on the outer circumference of the second shaft 50, which is located inside the first through hole 222. The outer ring 223b is positioned radially outward from the inner ring 223a. The outer ring 223b is fixed to the first body portion 221. The rolling elements 223c are positioned between the inner ring 223a and the outer ring 223b. The rolling elements 223c are balls or rollers. However, the first bearing 223 may also be a sliding bearing.

[0028] As shown in Figures 1 and 2, the first flat plate 212a is connected to the upper ends of the blades 211a and 211b, respectively. More specifically, the first main body 221 of the first flat plate 212a is connected to the upper ends of the blades 211a and 211b, respectively. When the blades 211a and 211b receive wind, they cause the first flat plate 212a and the second flat plate 212b to rotate around the central axis of the drag-type wind turbine 10, causing the first main body 221 to rotate. In addition, the outer ring 223b of the first bearing 223 rotates in conjunction with the rotation of the first main body 221. On the other hand, the inner ring 223a of the first bearing 223 does not rotate. The first flat plate 212a can be rotatably supported by the first bearing 223 with such a simple configuration.

[0029] The first flat plate 212a further includes, for example, a first guide rib 214 into which the upper end of the blade 211a is fitted, and a second guide rib 215 into which the upper end of the blade 211b is fitted. In the examples shown in Figures 2 and 4, each of the first guide rib 214 and the second guide rib 215 of the first flat plate 212a is composed of a pair of protruding walls that project downward (towards the -Z side) from the lower surface of the first flat plate 212a.

[0030] The upper end of the blade 211a is fitted between a pair of protruding walls that make up the first guide rib 214. The upper end of the blade 211b is fitted between a pair of protruding walls that make up the second guide rib 215.

[0031] As shown in Figure 5, the second flat plate 212b has a main body (second main body) 231, a through hole (second through hole) 232, and a bearing (second bearing 233). The second main body 231 has a substantially disc shape that rotates with respect to the central axis of the drag-type wind turbine 10. That is, the second main body 231 has a substantially circular shape in plan view. However, the second main body 231 may have a shape other than substantially circular, such as a substantially ellipse, in plan view.

[0032] The second through-hole 232 is positioned to coincide with the central axis of the drag-type wind turbine 10. The second through-hole 232 is defined by the inner surface of the second main body 231. The second shaft 50 is located inside the second through-hole 232. In plan view, the second through-hole 232 has a substantially circular shape. However, in plan view, the second through-hole 232 may have a shape other than substantially circular, such as a substantially elliptical shape.

[0033] The second bearing 233 is attached to the second body 231. In the example shown in Figure 5, the second bearing 233 is located on the lower side of the second body 231. The second bearing 233 is provided facing the connecting member 40. The second bearing 233 supports the second body 231. In the example shown in Figure 5, the second bearing 233 is a rolling bearing. The second bearing 233 has an inner ring 233a, an outer ring 233b, and rolling elements 233c. The inner ring 233a is mounted on the outer circumference of the second shaft 50 located inside the second through hole 232. The outer ring 233b is located radially outward from the inner ring 233a. The outer ring 233b is fixed to the second body 231. The rolling elements 233c are located between the inner ring 233a and the outer ring 233b. The rolling elements 233c are balls or rollers. However, the second bearing 233 may be a sliding bearing.

[0034] As shown in Figures 1 and 2, the second plate 212b is connected to the lower end of blade 211a and the lower end of blade 211b, respectively. More specifically, the second body portion 231 of the second plate 212b is connected to the lower end of blade 211a and the lower end of blade 211b, respectively. When blades 211a and 211b receive wind, they cause the first plate 212a and the second plate 212b to rotate around the central axis of the drag-type wind turbine 10, causing the second body portion 231 to rotate. In addition, the outer ring 233b of the second bearing 233 rotates as the second body portion 231 rotates. On the other hand, the inner ring 233a of the second bearing 233 does not rotate. The second plate 212b can be rotatably supported by the second bearing 233 with such a simple configuration. Therefore, the cost of the drag-type wind turbine 10 can be reduced.

[0035] The second flat plate 212b may also have a first guide rib 214 and a second guide rib 215. The first guide rib 214 of the second flat plate 212b fits the lower end of the blade 211a. The second guide rib 215 of the second flat plate 212b also fits the lower end of the blade 211b. In the examples shown in Figures 2 and 5, the first guide rib 214 and the second guide rib 215 of the second flat plate 212b are each composed of a pair of protruding walls that project upward (towards the +Z side) from the upper surface of the second flat plate 212b.

[0036] By supporting the blade 211a on the first guide rib 214, the blade 211a can be stably fixed in a position approximately perpendicular to the first plate 212a and the second plate 212b, respectively. Similarly, by supporting the blade 211b on the second guide rib 215, the blade 211b can be stably fixed in a position approximately perpendicular to the first plate 212a and the second plate 212b, respectively. As a result, the rotational stability of the blades 211a and 211b can be improved, and the power generation efficiency of the drag-type wind turbine 10 can be improved by reducing mechanical losses.

[0037] In the blade stage 21b, the configuration of blades 211c and 211d may be the same as that of blades 211a and 211b. The third flat plate 212c of the blade stage 21b is connected to the upper ends of blades 211c and 211d. A third guide rib 216 for fitting the upper end of blade 211c may be provided on the lower surface of the third flat plate 212c. Alternatively, a fourth guide rib 217 for fitting the upper end of blade 211d may be provided on the lower surface of the third flat plate 212c. The first flat plate 212a of the blade stage 21b is connected to the lower ends of blades 211c and 211d. A third guide rib 216 for fitting the lower end of blade 211c may be provided on the upper surface of the first flat plate 212a. Alternatively, a fourth guide rib 217 for fitting the lower end of blade 211d may be provided on the upper surface of the first flat plate 212a. The configuration of the third guide rib 216 and the fourth guide rib 217 may be the same as that of the first guide rib 214 and the second guide rib 215.

[0038] As shown in Figure 6, the third plate 212c has a main body (third main body) 241, a through hole (third through hole) 242, and a bearing (third bearing) 243. The third main body 241 has a substantially disc shape that rotates with respect to the central axis of the drag-type wind turbine 10. That is, the third main body 241 has a substantially circular shape in plan view. However, the third main body 241 may have a shape other than substantially circular, such as a substantially ellipse, in plan view.

[0039] The third through-hole 242 is positioned to coincide with the central axis of the drag-type wind turbine 10. The third through-hole 242 is defined by the inner surface of the third main body 241. The second shaft 50 is located inside the third through-hole 242. In plan view, the third through-hole 242 has a substantially circular shape. However, in plan view, the third through-hole 242 may have a shape other than substantially circular, such as a substantially elliptical shape.

[0040] The third bearing 243 is attached to the third main body 241. In the example shown in Figure 6, the third bearing 243 is located on the upper side of the third main body 241. The third bearing 243 is provided so as to face the retaining member 60 and the upper beam 71 of the frame 70. However, the third bearing 243 may also be located on the lower side of the third main body 241. The third bearing 243 supports the third main body 241. In the example shown in Figure 6, the third bearing 243 is a rolling bearing. The third bearing 243 has an inner ring 243a, an outer ring 243b, and rolling elements 243c. The inner ring 243a is mounted on the outer circumference of the second shaft 50 located inside the third through hole 242. The outer ring 243b is located radially outward from the inner ring 243a. The outer ring 243b is fixed to the third main body 241. The rolling element 243c is positioned between the inner ring 243a and the outer ring 243b. The rolling element 243c is either a ball or a roller. However, the third bearing 243 may be a sliding bearing.

[0041] When the blades 211c and 211d receive wind, they cause the first plate 212a and the third plate 212c to rotate around the central axis of the drag-type wind turbine 10, causing the third main body 241 to rotate. In addition, the outer ring 243b of the third bearing 243 rotates in conjunction with the rotation of the third main body 241. On the other hand, the inner ring 243a of the third bearing 243 does not rotate. The third bearing 243, with its simple configuration, can rotatably support the third plate 212c.

[0042] <Power generation unit 30> An example of the configuration of the power generation unit 30 will be described with reference to Figures 7 and 8. Figure 7 is a schematic longitudinal cross-sectional view showing the power generation unit 30 of the drag-type wind turbine 10 according to the first embodiment. Figure 8 is a schematic perspective view showing the power generation unit 30 of the drag-type wind turbine 10 according to the first embodiment.

[0043] As shown in Figures 7 and 8, the power generation unit 30 includes a generator 31 having a rotor (not shown) and a stator (not shown), and a shaft 32. The shaft 32 is connected to the rotor of the generator 31. For convenience of explanation, the shaft 32 will be referred to as the "first shaft 32" below. The power generation unit 30 generates electricity in accordance with the rotation and torque of the first shaft 32.

[0044] The power generation unit 30 may be an AC generator equipped with a core winding with 10 poles or less. Furthermore, a generator equipped with a core winding with 10 poles or less is a generator that utilizes or repurposes a brushless motor equipped with a core winding. In other words, compared to a dedicated generator, a brushless motor equipped with a core winding, which is generally produced in large quantities, can be repurposed as the power generation unit 30, thus reducing costs. However, the configuration of the power generation unit 30 is not limited to this.

[0045] The power generation unit 30 may further include a case 33, support members such as ball bearings (not shown), a first fixing plate 34 for fixing the generator 31, a second fixing plate 35 for fixing the case 33, V-rings 36a, 36b, O-ring 36c, a grommet 37a, a power supply line 37b, and other components. This improves the dustproof and waterproof properties of the drag-type wind turbine 10 which is placed outdoors. For the sake of explanation, the middle section of the power supply line 37b is omitted in Figure 7. The power generation unit 30 is electrically connected to an external load. The power generation unit 30 may also be electrically connected to an external load via a power conversion device that converts the power output from the power generation unit 30.

[0046] As shown in Figure 8, the power generation unit 30 is connected to the lower beam 72 of the frame 70 (see Figures 1 and 2). More specifically, the lower surface of the second fixing plate 35 of the power generation unit 30 is connected to the lower beam 72. On the other hand, the upper surface of the second fixing plate 35 is connected to the first fixing plate 34. Preferably, the first fixing plate 34, the second fixing plate 35, and the lower beam 72 are made of a material with excellent heat dissipation properties, such as metal. This allows the heat from the generator 31 during power generation to be dissipated (heat exhausted) to the outside of the power generation unit 30 via the first fixing plate 34, the second fixing plate 35, and the lower beam 72. This reduces the possibility of the temperature of the power generation unit 30 becoming excessively high during power generation. However, the power generation unit 30 does not necessarily have to be connected to the lower beam 72 of the frame 70.

[0047] <Connecting member 40> An example of the configuration of the connecting member 40 will be described with reference to Figures 9 and 10. Figure 9 is a perspective view showing an example of the connection configuration between the second flat plate 212b and the connecting member 40 of the drag-type wind turbine 10 according to the first embodiment. Figure 10 is a longitudinal cross-sectional view of the connecting member 40 provided in the drag-type wind turbine 10 according to the first embodiment.

[0048] In the examples shown in Figures 9 and 10, the connecting member 40 connects the second plate 212b and the power generation unit 30. One example of the connecting member 40 is a rigid coupling. By using a coupling as the connecting member 40, the second plate 212b and the power generation unit 30 can be connected with a simple configuration. Alternatively, a flexible coupling may be used as the connecting member 40. By using a flexible coupling as the connecting member 40, misalignment between the central axis of the power generation unit 30 and the central axis of the drag-type wind turbine 10 can be tolerated, absorbing uneven wear of the second bearing 233 and vibrations of components such as the second plate 212b, thereby improving quietness. However, the connecting member 40 may be a different component from a coupling, as long as it has a configuration that can connect the second plate 212b and the power generation unit 30.

[0049] As shown in Figures 9 and 10, the connecting member 40 has a first hole 41, a second hole 42, a pin 43, and a screw insertion hole 44. The first hole 41 is recessed upward from the lower surface of the connecting member 40. The first shaft 32 of the power generation unit 30 is fitted into the first hole 41. The connecting member 40 and the power generation unit 30 are connected when the first shaft 32 is fitted into the first hole 41 and fastened and secured with a screw.

[0050] The second hole 42 is recessed downward from the upper surface of the connecting member 40 (the surface facing the second flat plate 212b). The second bearing 233 is fitted into the second hole 42. The pin 43 protrudes from the upper surface of the connecting member 40 toward the second flat plate 212b. The second flat plate 212b has a pin insertion hole 234 into which the pin 43 is inserted. The screw insertion hole 44 is a hole through which a screw 441 is inserted to fix the connecting member 40 to the second flat plate 212b. The screw insertion hole 44 penetrates the connecting member 40 radially and communicates with the second hole 42. The screw 441 inserted through the screw insertion hole 44 contacts the outer surface of the second bearing 233 fitted into the second hole 42. The second bearing 233 is fitted into the second hole 42, and the pin 43 is inserted into the pin insertion hole 234. The second bearing 233 is then fastened and secured with a screw 441, thereby connecting the connecting member 40 and the second plate 212b. As a result, the second plate 212b and the first shaft 32 of the power generation unit 30 are connected via the connecting member 40.

[0051] The second plate 212b and the first shaft 32 of the power generation unit 30 are connected via a connecting member 40, thereby transmitting the rotational motion (speed and torque) of the second plate 212b to the first shaft 32. In other words, the rotational motion (speed and torque) of the blade stage 21 can be transmitted to the first shaft 32 via the second plate 212b and the connecting member 40. This prevents the blade stage 21 from free-rotating relative to the first shaft 32 with a simple configuration. Furthermore, because the rotational motion (speed and torque) of the blade stage 21 can be transmitted to the first shaft 32 with a simple configuration, the cost of the drag-type wind turbine 10 can be reduced.

[0052] <Holding member 60> An example of the configuration of the retaining member 60 will be described with reference to Figures 11 and 12. Figure 11 is a longitudinal cross-sectional view showing an example of the retaining member 60 provided in the drag-type wind turbine 10 according to the first embodiment. Specifically, Figure 11(a) is a longitudinal cross-sectional view showing a part of the drag-type wind turbine 10, which is the region including the retaining member 60, cut along the XZ plane. Figure 11(b) is a longitudinal cross-sectional view showing a part of the drag-type wind turbine 10, which is the region including the retaining member 60, cut along the YZ plane. Figure 12 is a longitudinal cross-sectional view showing another example of the retaining member 60 provided in the drag-type wind turbine 10 according to the first embodiment.

[0053] As shown in Figure 11(a), the holding member 60 includes a bearing 61 that supports the second shaft 50, a housing 62 that houses the bearing 61, and a connecting member 63 that connects the housing 62 to the upper beam 71 of the frame 70. Thus, the holding member 60 holds the second shaft 50 while connected to the frame 70. The upper end of the second shaft 50 is fixed to the upper beam 71 of the frame 70.

[0054] The bearing 61 is, for example, a spherical plain bearing. The inner surface of the bearing 61 is in contact with the second shaft 50. The outer surface of the bearing 61 is in contact with the inner surface of the housing 62. By using a spherical plain bearing 61, the outer surface of the bearing 61 can be slid against the inner surface of the housing 62. Furthermore, since spherical plain bearings have an auto-aligning function, the second shaft 50 supported by the bearing 61 can be properly supported by the upper beam 71 of the frame 70.

[0055] The connecting member 63 includes, for example, a bolt 631, a nut 632, and a collar 633. The bolt 631 penetrates the side end piece 621 of the housing 62 and reaches the upper beam 71. The nut 632 is positioned above the side end piece 621 of the housing 62 and holds the bolt 631. The collar 633 is fitted around the outer circumference of the bolt 631 and is positioned between the side end piece 621 of the housing 62 and the upper beam 71. However, the configuration of the connecting member 63 is not limited to this.

[0056] As shown in Figure 11(b), the bearing 61 may further have a screw insertion hole 611 that reaches the second shaft 50, and a screw 612 that is inserted into the screw insertion hole 611. The second shaft 50 is fastened and fixed to the bearing 61 by the screw 612 inserted into the screw insertion hole 611.

[0057] The bearing 61 supports the second shaft 50 in a suspended state. In other words, the bearing 61 supports the blade stage 21 via the second shaft 50. This reduces the load from the blade stage 21 applied to the power generation unit 30.

[0058] The configuration of the retaining member 60 is not limited to the configuration shown in Figure 11. The retaining member 60 does not need to have a bearing 61 such as a spherical sliding bearing, as long as it has a configuration that can hold the second shaft 50. If the drag-type wind turbine 10 has only blade stages 21a, the retaining member 60 may be placed between the first flat plate 212a and the upper beam 71 of the frame 70. In this case, the first bearing 223 of the first flat plate 212a faces the retaining member 60.

[0059] Referring to Figure 12, an example of the configuration of the retaining member 60 without a spherical plain bearing will be described. As shown in Figure 12, the bearing 64 has a hole 641 through which the second shaft 50 is inserted. The second shaft 50, inserted through the hole 641, is fastened and fixed to the bearing 64 by a screw (not shown) inserted into a screw insertion hole (not shown) provided in the bearing 64. In the example shown in Figure 12, the second shaft 50 is fastened and fixed to the bearing 64 by a screw inserted into a screw insertion hole. The bearing 64 supports the second shaft 50 in a suspended state. That is, the bearing 64 supports the blade stage 21 via the second shaft 50. This reduces the load from the blade stage 21 applied to the power generation unit 30.

[0060] [Second Embodiment] <Wind power generation system 1> Next, with reference to Figure 13, an example of the overall configuration of the wind power generation system 1 according to the second embodiment will be described. Figure 13 is a schematic block diagram showing the overall configuration of the wind power generation system 1. In the example shown in Figure 13, the wind power generation system 1 includes a drag-type wind turbine 10 according to the first embodiment.

[0061] As shown in Figure 13, the wind power generation system 1 further includes a power conversion device 2 in addition to the drag wind turbine 10. The wind power generation system 1 may also further include other components such as a rectifier circuit 3 and a diode 4. The rectifier circuit 3 is electrically connected to the drag wind turbine 10. The rectifier circuit 3 converts the AC power output from the drag wind turbine 10 into DC power.

[0062] Diode 4 is positioned between the rectifier circuit 3 and the power converter 2. Power (current and voltage) output from the drag-type wind turbine 10 is transmitted to the power converter 2 through the rectifier circuit 3 and diode 4. Diode 4 prevents reverse current flow from the power converter 2 to the rectifier circuit 3.

[0063] The power converter 2 converts and outputs power from the drag-type wind turbine 10. As shown in Figure 13, the power converter 2 includes, for example, a detection unit 2a, an arithmetic processing unit 2b, and an adjustment unit 2c. The power converter 2 may also further include other components such as a wind speed detection unit (for example, a wind speed sensor).

[0064] The detection unit 2a detects the current and voltage output from the drag-type wind turbine 10. Examples of the detection unit 2a include a current sensor and a voltage sensor. The types of current sensors and voltage sensors are not limited. The detection unit 2a outputs detection signals indicating the detected current and voltage values ​​to the arithmetic processing unit 2b.

[0065] The arithmetic processing unit 2b calculates the optimal current and voltage to obtain maximum power based on the current and voltage output from the drag-type wind turbine 10. The arithmetic processing unit 2b may be an arithmetic processing circuit such as a microcomputer, which includes, for example, a processor 2b1 such as a CPU (Central Processing Unit), a memory 2b2 such as a ROM (Read Only Memory) and flash memory, and an input / output interface 2b3 for inputting and outputting various signals. The processor 2b1 controls the operation of the arithmetic processing unit 2b according to the program stored in the memory 2b2. The memory 2b2 is an example of a storage medium for storing a program.

[0066] The optimal current and voltage combination for obtaining maximum power varies depending, for example, on the wind speed acting on the drag-type wind turbine 10. The arithmetic processing unit 2b may calculate the optimal current and voltage using the wind speed acting on the drag-type wind turbine 10. The arithmetic processing unit 2b may obtain the wind speed value from the wind speed sensor of the power converter 2, or it may calculate the wind speed value by referring to a characteristic table stored in memory 2b2 from the current and voltage values ​​obtained from the detection unit 2a. The arithmetic processing unit 2b outputs control signals to the adjustment unit 2c to adjust the current and voltage output from the drag-type wind turbine 10 to the optimal current and voltage. As an example, the arithmetic processing unit 2b outputs a PWM (Pulse Width Modulation) signal to the adjustment unit 2c to adjust to the optimal current and voltage.

[0067] The adjustment unit 2c adjusts the current and voltage output from the drag-type wind turbine 10 to the optimal current and voltage in accordance with the control signal from the calculation processing unit 2b. Examples of the adjustment unit 2c include a step-down converter circuit, a step-up converter circuit, and a step-up / step-down converter circuit.

[0068] As a result of the adjustment unit 2c adjusting the current and voltage output from the drag-type wind turbine 10 to the optimal current and voltage, the power output from the drag-type wind turbine 10 is converted by the power converter 2.

[0069] Although preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various modifications and substitutions can be made to the embodiments described above without departing from the scope of the present invention.

[0070] Examples of the present invention are as follows: <1> A vertical-axis drag-type wind turbine, The blade and A first flat plate connected to the upper end of the blade, A second flat plate connected to the lower end of the blade, A power generation unit having a generator and a first shaft connected to the generator, A connecting member fixed to one of the first plate and the second plate, and having a first hole into which the first shaft of the power generation unit is fitted, A second shaft is arranged along the central axis of the aforementioned drag-type wind turbine, A retaining member that holds the aforementioned second shaft, Equipped with, Each of the first and second plates has a main body that rotates with respect to the central axis of the drag-type wind turbine, and a through hole positioned to coincide with the central axis. The second shaft, while held by the holding member, is inserted through the respective through holes of the first and second plates. In accordance with the rotation of the first and second plates, the first shaft of the power generation unit rotates, while the second shaft, which is held by the holding member, does not rotate. Drag type windmill. <2> The connecting member has a pin that protrudes toward the flat plate side of the first and second flat plates to which the connecting member is fixed. The first and second flat plates, the one to which the connecting member is fixed, has a pin insertion hole for inserting the pin. The aforementioned <1> A drag-type wind turbine as described above. <3> At least one of the first plate and the second plate further has a bearing attached to the main body, The bearing has an inner ring mounted on the outer circumference of the second shaft, which is located inside the through hole. The aforementioned <1> or the above <2> A drag-type wind turbine as described above. <4> The aforementioned connecting member is a coupling. The aforementioned <1> from the above <3> A drag-type wind turbine as described in any one of the following. <5> A wind power generation system equipped with a vertical-axis drag-type wind turbine, The aforementioned drag-type wind turbine is The blade and A first flat plate connected to the upper end of the blade, A second flat plate connected to the lower end of the blade, A power generation unit having a generator and a first shaft connected to the generator, A connecting member fixed to one of the first plate and the second plate, and having a first hole into which the first shaft of the power generation unit is fitted, A second shaft is arranged along the central axis of the aforementioned drag-type wind turbine, A retaining member that holds the aforementioned second shaft, Equipped with, Each of the first and second plates has a main body that rotates with respect to the central axis of the drag-type wind turbine, and a through hole positioned to coincide with the central axis. The second shaft, while held by the holding member, is inserted through the respective through holes of the first and second plates. In accordance with the rotation of the first and second plates, the first shaft of the power generation unit rotates, while the second shaft, which is held by the holding member, does not rotate. Wind power generation system. [Explanation of Symbols]

[0071] 1... Wind power generation system, 10... Drag-type wind turbine, 211... Blades, 212... Flat plate, 214... First guide rib, 215... Second guide rib, 30... Power generation section, 32... First shaft, 40... Connecting member, 41... First hole, 42... Second hole, 43... Pin, 50... Second shaft, 60... Holding member, 70... Mounting frame

Claims

1. A vertical-axis drag-type wind turbine, The blade and A first flat plate connected to the upper end of the blade, A second flat plate connected to the lower end of the blade, A power generation unit having a generator and a first shaft connected to the generator, A connecting member fixed to one of the first plate and the second plate, and having a first hole into which the first shaft of the power generation unit is fitted, A second shaft is arranged along the central axis of the aforementioned drag-type wind turbine, A retaining member that holds the second shaft, Equipped with, Each of the first and second plates has a main body that rotates with respect to the central axis of the drag-type wind turbine, and a through hole positioned to coincide with the central axis. The second shaft, while held by the holding member, is inserted through the respective through holes of the first and second plates. In accordance with the rotation of the first and second plates, the first shaft of the power generation unit rotates, while the second shaft, which is held by the holding member, does not rotate. Drag type windmill.

2. The connecting member has a pin that protrudes toward the flat plate side of the first and second flat plates to which the connecting member is fixed. The first plate and the second plate to which the connecting member is fixed have a pin insertion hole for inserting the pin. The drag-type wind turbine according to claim 1.

3. At least one of the first plate and the second plate further has a bearing attached to the main body, The bearing has an inner ring mounted on the outer circumference of the second shaft, which is located inside the through hole. A drag-type wind turbine according to claim 1 or claim 2.

4. The aforementioned connecting member is a coupling. A drag-type wind turbine according to claim 1 or claim 2.

5. A wind power generation system equipped with a vertical-axis drag-type wind turbine, The aforementioned drag-type wind turbine is The blade and A first flat plate connected to the upper end of the blade, A second flat plate connected to the lower end of the blade, A power generation unit having a generator and a first shaft connected to the generator, A connecting member fixed to one of the first plate and the second plate, and having a first hole into which the first shaft of the power generation unit is fitted, A second shaft is arranged along the central axis of the aforementioned drag-type wind turbine, A retaining member that holds the second shaft, Equipped with, Each of the first and second plates has a main body that rotates with respect to the central axis of the drag-type wind turbine, and a through hole positioned to coincide with the central axis. The second shaft, while held by the holding member, is inserted through the respective through holes of the first and second plates. In accordance with the rotation of the first and second plates, the first shaft of the power generation unit rotates, while the second shaft, which is held by the holding member, does not rotate. Wind power generation system.

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