JP2005061291A - Windmill structure of wind power generation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a windmill structure capable of preventing damage due to strong wind. <P>SOLUTION: In the windmill structure of a wind power generation device driving a generator by rotation of a windmill provided with one or a plurality of radially extending blades, the blades include a frame body composed of a center rod extending from a blade support part in a radial direction, an upper part rod attached to a tip part of the center rod, a lower part rod rotatably attached to a base end part of the center rod, and a side edge rod, and sheet part stretched in a space surrounded by the frame body, and a control means rotating the lower part rod in response to wind speed is included. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a structure of a windmill having a plurality of blades in a wind power generator.

  2. Description of the Related Art A wind power generator that generates power by rotating a windmill including a plurality of propeller blades (blades) is known. FIG. 5 is a diagram schematically showing one conventional example of such a wind turbine generator. In the wind power generator of FIG. 5, the windmill 100 and the power generation unit are installed at the upper end of the support column 115. The windmill 100 includes three blades 120a, 120b, and 120c arranged at equal angular intervals extending radially from the central blade support portion 113. The blade support part 113 is connected to the main shaft 111 via the main bearing 112, and the rotation of the windmill is transmitted to the main shaft 111. The rotor of the generator 114 is driven by the rotation of the main shaft 111 to generate electricity.

Usually, a sensor 116 such as an anemometer and an anemometer is also attached, and the windmill 100 is directed in the direction in which the wind blows based on information from the anemometer. That is, the windmill 100 is rotated about the support column 115 as indicated by an arrow R1. The windmill 100 rotates as indicated by an arrow R2 by the wind blowing from the front. There are many known technologies such as Patent Documents 1 and 2 for a wind turbine generator having such a windmill.
JP-A-8-128385 JP 2000-87841 A

  As described above, a windmill including radial blades may be damaged by a strong wind exceeding the durability of the windmill. From the viewpoint of wind power generation efficiency, it is preferable to increase the wind receiving area of the blades, but durability against strong winds is reduced. Therefore, a shape in which the blades are thinned to withstand strong winds and the blades are long in order to increase the wind receiving area as much as possible is often used.

  Patent Documents 1 and 2 disclose a structure for preventing breakage by controlling the effective area for receiving wind by changing the angle of one blade with respect to wind as a countermeasure against strong wind. By making the surface of the blade parallel to the direction of the wind, the resistance to the wind is made zero.

  However, as shown in FIG. 5, the blades of the windmill are not flat but twisted so as to draw a spiral from the base end to the tip like a propeller. This is because the shape is suitable for obtaining rotational force, that is, for obtaining higher power generation efficiency. However, even if the mounting angle of the blade 120a or the like twisted in this manner with respect to the blade support portion 113 is changed, that is, the blade 120a or the like is rotated around the axis C, the entire surface of the blade is parallel to the wind. Can not be. In such a blade having a spirally twisted surface, any part is always subjected to wind resistance, and may be damaged by strong winds exceeding durability.

  In view of the above-described problems, the present invention includes a blade having a spiral surface suitable for obtaining high power generation efficiency in a wind turbine structure of a wind turbine generator, and can prevent breakage due to strong wind. The purpose is to provide a structure.

In order to achieve the above object, the present invention provides the following wind turbine structure.
(1) The wind turbine structure of the wind turbine generator according to claim 1 transmits the rotation of the wind turbine including one or a plurality of blades extending radially from the blade support portion at the tip of the main shaft to the main shaft. It is a windmill structure of the wind power generator which drives a generator. A center rod extending radially from the blade support portion, a top rod attached to a tip portion of the center rod via a connecting portion, and a base rod of the center rod with the center rod as an axis It has a frame composed of a lower rod that is pivotably attached, and a side edge rod that is attached via a connecting portion so as to connect the tip ends of the upper rod and the lower rod. Furthermore, it has a sheet | seat part stretched in the space enclosed by the frame which consists of these four rods. Still further, there is provided control means for rotating the lower rod so as to change an angle of the lower rod with respect to the upper rod viewed from the axial direction of the central rod in accordance with a wind speed.

(2) The wind turbine structure of the wind turbine generator according to claim 2 is characterized in that, in claim 1, an angle range for rotating the lower rod is a range of 90 degrees.

(3) The wind turbine structure of the wind turbine generator according to claim 3 is the wind turbine structure according to claim 2, wherein the range of 90 degrees is between a direction perpendicular to the main axis and a direction parallel to the main axis. It is characterized by.

(4) The wind turbine structure of the wind turbine generator according to claim 4 is the rod-shaped rotation support portion extending from the tip end portion of the lower rod toward the blade support portion according to any one of claims 1 to 3, The rotation guide groove is formed on the blade support portion, and the rotation support portion moves in the rotation guide groove as the lower rod rotates.

(5) The wind turbine structure of the wind turbine generator according to claim 5 is characterized in that in any one of claims 1 to 4, the sheet portion is a sheet made of stainless steel fibers.

  A wind turbine structure of a wind turbine generator according to the present invention includes a frame body composed of four rods, a center rod, an upper rod, a lower rod, and a side edge rod, and a seat portion stretched in a space surrounded by the frame body. Each blade extends radially from the blade support.

  When the wind speed is within the allowable range, the lower rod is at a position that forms a predetermined angle with the upper rod when viewed from the axial direction of the center rod. Preferably, the angle is 90 degrees, and more preferably, the lower rod faces in a direction perpendicular to the main axis, and the upper rod faces in a direction parallel to the main axis. At this time, the sheet portion forms a spirally twisted surface. Thereby, it becomes a blade | wing shape which can convert wind energy efficiently into rotational energy.

  When the wind speed exceeds the allowable range, the lower rod is rotated by a predetermined angle, and the angle formed with the upper rod is changed (specifically, reduced). Thereby, the twist of the spiral surface of a sheet | seat part becomes small, and it becomes a blade shape nearer to a plane. Further, the direction of the blades is close to the direction parallel to the wind, and the wind pressure received is reduced. In the most extreme case, the lower rod is rotated to a position where the angle between the lower rod and the upper rod is 0 degree, that is, parallel. Thus, the blade shape is completely flat and parallel to the wind direction. At this time, the wind pressure is not received at all.

  In the present invention, by controlling the rotation angle of the lower rod according to the wind speed, the blade shape is changed between the spiral shape and the planar shape, and the direction of the blade is changed from the direction receiving the wind pressure to the direction not receiving at all. And can be changed. As a result, damage to the blades due to wind pressure can be prevented. Moreover, the shape of the blades can be widened to increase the wind receiving area, and the shape can be made high in conversion efficiency. Furthermore, in the case of the same wind receiving area, the length of the blades can be made shorter than before by increasing the width, so that it can be constructed compactly and at low cost.

  FIG. 1 is a schematic external perspective view showing a wind turbine structure of a wind turbine generator according to the present invention. The windmill 10 is installed with a generator at the upper end of a support (not shown). A blade support portion 13 is attached via a main bearing 12 to a tip portion (left side in FIG. 1) of the main shaft 11 for driving a generator (not shown). Three blades 20 a, 20 b, and 20 c that extend radially with respect to the main shaft 11 are attached to the illustrated blade support portion 13 at equal angular intervals. The axis of the main shaft 11 is denoted by reference numeral C1. The axis C1 of the main shaft 11 is rotationally controlled so as to face the blowing wind (arrow R1). This rotation control is performed by an output signal from an anemometer (not shown).

  The wind turbine structure according to the present invention is characterized by the structure of one blade. Therefore, each blade has the same structure, and the number of blades may be one or plural. When the blades 20a and the like rotate together with the blade support portion 13 by the wind, the rotation is transmitted to the main shaft 11 (arrow R2), and the generator is driven by the rotation of the main shaft 11 to generate electric power.

  The structure of one blade 20a will be described. The blade | wing 20a comprises the frame comprised from four rods. The 1st rod which comprises a frame is the center rod 21 with which a base end part is attached on the blade | wing support part 13, and is extended to radial direction with respect to the axis | shaft C1. The axis | shaft of the center rod 21 is shown with code | symbol C2. The second rod is an upper rod 23 attached to the tip of the center rod 21 via a connecting portion 27. The third rod is a lower rod 24 that is rotatably attached to the proximal end portion (including the vicinity of the proximal end portion) of the central rod 21 with the central rod 21 as an axis. Further, the fourth rod is a side edge rod 22 attached via connecting portions 28 and 29 to connect the tip ends of the upper rod 23 and the lower rod 24, respectively. The material of the rod may be a lightweight and strong rigid body, for example, made of metal. The connecting portions 27, 28, and 29 are connected so that both connected rods can be bent in either direction.

  Furthermore, it has the sheet | seat part 26 extended | stretched in the space enclosed by the frame which consists of these four rods 21, 22, 23, and 24. FIG. The area facing the wind of the seat portion 26 serves as a wind receiving area that actually receives the wind. The seat part 26 is made of a flexible and elastic sheet material, and is preferably lightweight and strong. For example, a sheet made of stainless steel fibers can be used. As will be described later, since the shape of the seat portion 26 is deformed as the lower rod 24 is rotated, the seat portion 26 is elastic and flexible enough to allow the deformation and maintain a tensioned state without slack. Cost.

  In the present invention, the lower rod 24 is controlled to rotate around the axis of the central rod 21 according to the wind speed (arrow R3). The control means includes a motor shaft 30 to which the base end portion of the lower rod 24 is connected, and a motor 31 that rotationally drives the motor shaft 30. Furthermore, an anemometer (not shown) that supplies a control signal to the motor 31. The anemometer generates an output signal corresponding to the wind speed and supplies it to the motor 31 as a control signal. In the illustrated example, a bearing 32 is interposed between the motor shaft 30 and the center rod 21, and the center rod 21 is not affected by the motor 31.

  The state of the lower rod 24 in FIG. 1 is when the wind speed is within the allowable range. In this case, the lower rod 24 is oriented in a direction substantially perpendicular to the axis C1 of the main shaft 11, while the upper rod 23 is rearward substantially parallel to the axis C1 of the main shaft 11 (rightward direction in FIG. 1). ) That is, the lower rod 24 and the upper rod 23 are substantially perpendicular (90 degrees) when viewed from the direction of the axis C2 of the center rod 21. Therefore, the sheet portion 26 forms a spiral twisted surface from the lower rod 24 toward the upper rod 23. In this state, the wind receiving area is the largest and the power generation efficiency is maximized.

  In the illustrated example, in order to smoothly rotate the lower rod 24, a rod-shaped rotation support portion 25 extending from the tip end portion of the lower rod 24 toward the blade support portion 13 is provided. In addition, a rotation guide groove 14 having a shape corresponding to the rotation range of the lower rod 24 is formed on the blade support portion 13. The distal end portion of the rotation support portion 25 is inserted into the rotation guide groove 14, and the rotation support portion 25 moves along the rotation guide groove 14 as the lower rod 24 rotates.

  In the state of FIG. 1, if the allowable range of the wind speed is exceeded, the motor 31 rotates the lower rod 24. As a result, the angle of the lower rod 24 relative to the upper rod 23 as viewed from the axial direction of the center rod 21 changes. Accordingly, the shape of the seat portion 26 and the direction with respect to the wind change, and the wind receiving area changes.

  Next, the mechanism of the wind turbine structure of the present invention will be described in more detail with reference to FIGS.

  FIG. 2A is a schematic external perspective view of the blades of the windmill in the same state as FIG. The direction of the white arrow represents the direction of the wind, and the thickness of the arrow relatively represents the wind speed (contrast with FIGS. 3 and 4). The lower rod 24 forms approximately 90 degrees with the upper rod 23 when viewed from the axial direction of the center rod 21. The surface of the sheet portion 26 has a spiral shape. FIG. 2B is a view of the blade state of FIG. 2A viewed from the axial direction of the center rod 21. At this time, the effective area directly facing the wind, that is, the wind receiving area is maximized. FIG. 2C is a diagram schematically showing an angle formed by the lower rod 24 and the upper rod 23 when viewed from the axial direction of the center rod 21 in the state of the blade of FIG. At this time, the angle formed by the lower rod 24 and the upper rod 23 is approximately 90 degrees, and the lower rod 24 faces a direction substantially perpendicular to the axis of the main shaft. On the other hand, the upper rod 23 faces the direction substantially along the axis of the main shaft.

  FIG. 3A is a schematic external perspective view of the blades of the windmill in a state where the lower rod 24 is rotated to a substantially intermediate position in the rotation range when the wind speed exceeds the allowable range in the state of FIG. It is. The wind speed is stronger than in the case of FIG. The lower rod 24 forms approximately 45 degrees with the upper rod 23 when viewed from the axial direction of the center rod 21. The side rod 22 rises from the state shown in FIG. 2 by the rotation of the lower rod 24 and pushes up the tip of the upper rod 23. The surface of the sheet portion 26 is spiral, but the twist is smaller than in the state of FIG. FIG. 3B is a view of the blade state of FIG. 3A viewed from the axial direction of the central rod 21. At this time, the effective area directly facing the wind, that is, the wind receiving area, is smaller than in the case of FIG. Thereby, the wind pressure which receives is smaller than the case of FIG. FIG. 3C is a diagram schematically showing an angle formed by the lower rod 24 and the upper rod 23 when viewed from the axial direction of the center rod 21 in the state of the blade of FIG. At this time, the angle formed by the lower rod 24 and the upper rod 23 is approximately 40 degrees. The direction of the upper rod 23 remains in the direction substantially along the axis of the main shaft.

  4A is a schematic external perspective view of the blades of the windmill in a state where the lower rod 24 is rotated to almost the final position in the rotation range when the wind speed exceeds the allowable range in the state of FIG. It is. The wind speed is even stronger than in the case of FIG. The lower rod 24 forms substantially 0 degree with the upper rod 23 when viewed from the axial direction of the central rod 21, that is, is parallel to the upper rod 23. The side edge rod 22 rises further than the state of FIG. 3 and pushes the tip of the upper rod 23 further. At this time, the sheet portion 26 is planar. FIG. 4B is a view of the state of the blade of FIG. 4A as viewed from the axial direction of the central rod 21. At this time, the effective area directly facing the wind, that is, the wind receiving area is almost zero, and hardly receives wind pressure. FIG. 4C is a diagram schematically showing an angle formed by the lower rod 24 and the upper rod 23 when viewed from the axial direction of the center rod 21 in the state of the blade of FIG. At this time, the angle formed by the lower rod 24 and the upper rod 23 is approximately 0 degrees.

  In FIG. 3 above, the lower rod 24 is rotated to a substantially intermediate position in the rotation range and stopped. However, the lower rod 24 can be stopped at any position within the rotation range of the lower rod 24. Needless to say. As described above, the angle range for rotating the lower rod 24 is approximately 90 degrees. As the lower rod 24 rotates in this range, the blade seat portion changes from a spiral shape to a planar shape, and the wind receiving area changes from the maximum direction to zero. As a result, the wind turbine can be prevented from being damaged by the wind speed exceeding the allowable range, and extremely high power generation efficiency can be obtained if the wind speed is within the allowable range.

  Preferably, the range of approximately 90 degrees, which is the rotation range of the lower rod 24, is between a direction perpendicular to the axis of the main axis and a direction parallel to the axis of the main axis. However, they may be displaced in any angular direction.

1 is a schematic external perspective view showing a wind turbine structure of a wind turbine generator according to the present invention. (A) is a schematic external perspective view of the blade | wing of a windmill in the same state as FIG. (B) is the figure which looked at the state of the blade | wing of (A) from the axial direction of the center rod. (C) is the figure which showed typically the angle which the lower rod and upper rod looked at from the axial direction of the center rod at the time of the blade | wing of (A). (A) is a schematic external perspective view of the blades of the windmill in a state where the lower rod is rotated to a substantially intermediate position in the rotation range when the wind speed exceeds the allowable range in the state of FIG. (B) is the figure which looked at the state of the blade | wing of (A) from the axial direction of the center rod. (C) is the figure which showed typically the angle which the lower rod 24 and upper rod looked at from the axial direction of the center rod in the state of the blade | wing of (A). (A) is a schematic external perspective view of the blades of the windmill in a state in which the lower rod 24 is rotated to almost the final position in the rotation range when the wind speed exceeds the allowable range in the state of FIG. 3. . (B) is the figure which looked at the state of the blade | wing of (A) from the axial direction of the center rod. (C) is the figure which showed typically the angle which the lower rod and upper rod looked at from the axial direction of the center rod at the time of the blade | wing of (A). It is the figure which showed one of the prior art examples of a wind power generator roughly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Windmill 11 Main shaft 12 Main bearing 13 Blade | wing support part 20a, 20b, 20c Blade | wing 21 Center rod 22 Side edge rod 23 Upper rod 24 Lower rod 25 Rotation support part 26 Seat part 27, 28, 29 Connection part 30 Motor shaft 31 Motor 32 Bearing 100 Windmill 111 Main shaft 112 Main bearing 113 Blade support 114 Generator 115 Strut 116 Sensor

Claims (5)

In the wind turbine structure of the wind turbine generator that drives the generator by transmitting the rotation of the wind turbine including one or more blades extending radially from the blade support portion at the tip of the main shaft to the main shaft,
A center rod extending radially from the blade support portion, a top rod attached to a tip portion of the center rod via a connecting portion, and a base rod of the center rod with the center rod as an axis Surrounded by the frame, a frame comprising a lower rod that is pivotally attached, and a side edge rod that is attached via a connecting portion to connect the tip of each of the upper rod and the lower rod. And a control means for rotating the lower rod so as to change the angle of the lower rod with respect to the upper rod as seen from the axial direction of the central rod according to the wind speed. A wind turbine structure of a wind turbine generator, comprising:   The wind turbine structure of the wind turbine generator according to claim 1, wherein an angle range in which the lower rod is rotated is a range of 90 degrees.   The wind turbine structure of the wind turbine generator according to claim 2, wherein the range of 90 degrees is between a direction perpendicular to the main axis and a direction parallel to the main axis.   A rod-shaped rotation support portion extending from the tip of the lower rod toward the blade support portion; and a rotation guide groove formed on the blade support portion, and accompanying the rotation of the lower rod The wind turbine structure of the wind turbine generator according to any one of claims 1 to 3, wherein the rotation support portion moves in the rotation guide groove.   The wind turbine structure of the wind power generator according to any one of claims 1 to 4, wherein the sheet portion is a sheet made of stainless steel fibers.

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