JP2007107483A - Straight wing vertical axis windmill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a straight wing vertical axis windmill of good windmill efficiency and startability and a simple structure. <P>SOLUTION: Three upper level straight wings 1a are attached on a rotation axis 3 via each upper arm 2a, and three lower level straight wing 1b are attached on the rotation axis 3 via each lower arm 2b. The rotation axis 3 is rotatably supported by a rotation axis column 4. The upper level straight wing 1a and the upper arm 2a form an upper level rotor 10a, and the lower level straight wing 1b and the lower arm 2b form a lower level rotor 10b. A ring shape end plate 5c is provided between the upper level rotor 10a and the lower level rotor 10b. The ring shape end plate 5c is connected or joined to a lower side wing tip of the upper level straight wing 1a by using a fastener such as a screw, and is connected or joined to an upper side wing tip of the lower level straight wing 1b. Consequently, the upper level rotor 10a and the lower level rotor 10b are integrated by the ring shape end plate 5c. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a straight blade vertical axis wind turbine.

  Straight-blade vertical axis wind turbines (that is, wind turbines with straight blades attached to the vertical shaft) have the characteristic that they are less susceptible to the effects of severe wind direction changes, and they are more structured than horizontal-axis wind turbines. There is an advantage such as simplicity. However, a straight blade vertical axis wind turbine generally has a problem in startability (self-startability). That is, when the wind speed is low, it may be difficult to start itself depending on the wind direction. Hereinafter, this problem will be described by taking a three-blade one-stage straight blade vertical axis wind turbine having no end plate as an example.

  FIG. 6 is a perspective view of a three-blade one-stage linear blade vertical axis wind turbine having no end plate. As shown in FIG. 6, in this conventional linear blade vertical axis windmill W1 (hereinafter referred to as “windmill W1” for short), three straight blades 101 are connected via an upper arm 102a and a lower arm 102b. Attached to the rotating shaft 103. Here, the rotating shaft 103 is rotatably supported by the rotating shaft column 104.

FIG. 7 is a graph showing the static torque of the conventional windmill W1 shown in FIG. 6 with respect to the rotor azimuth, and also shows the average static torque. The “average static torque” is a static torque generated when a wind with a wind speed of 3 m / s hits a stationary blade in a fixed rotor azimuth range (between −180 degrees and 180 degrees). Is the average value. As is apparent from FIG. 7, the conventional wind turbine W1 shown in FIG. 6 has a drawback that the static torque tends to depend on the rotor azimuth angle, that is, the wind direction, although the average static torque is large. On the other hand, there are two improvement measures. That is, the first improvement measure is to increase the number of wings, and the second improvement measure is to stack the wings with different phases (see, for example, Patent Document 1).
JP 2002-235656 A (paragraph [0022], FIG. 1)

  FIG. 8 is a perspective view of a six-blade one-stage linear blade vertical axis wind turbine according to the first improvement measure. FIG. 9 is a graph showing the static torque of the straight blade vertical axis wind turbine shown in FIG. 8 with respect to the rotor azimuth, and also shows the average static torque. As shown in FIG. 8, in this conventional linear blade vertical axis windmill W2 (hereinafter referred to as “windmill W2” for short), six straight blades 101 are connected via an upper arm 102a and a lower arm 102b. Attached to the rotating shaft 103. As is apparent from FIG. 9, the conventional wind turbine W2 shown in FIG. 8 has a drawback that the average static torque is reduced although the fluctuation of the static torque due to the rotor azimuth angle, that is, the wind direction is improved. In addition, there is a disadvantage that the windmill efficiency is lowered.

  Further, for example, in the straight blade vertical axis wind turbine according to the second improvement measure disclosed in Patent Document 1, although the fluctuation of the static torque due to the wind direction and the average static torque are improved, the upper rotor and the lower rotor There is a drawback that the structure becomes complicated because it is necessary to install a gantry between them and to strengthen the structural strength by providing a column. Therefore, it is necessary to develop a straight blade vertical axis wind turbine having a simple structure while taking into consideration startability and wind turbine efficiency.

  The present invention has been made to solve the above-described conventional problems, and it is an object or object of the present invention to provide a straight-blade vertical axis wind turbine having good wind turbine efficiency and good startability and a simple structure. Let it be an issue.

  A straight blade vertical axis wind turbine according to the present invention made to solve the above-described problem is a rotor having a straight blade attached to a rotating shaft, arranged in multiple stages in the direction in which the rotating shaft extends, and the rotating shaft circumference of the straight blade In a linear blade vertical axis wind turbine in which the mounting position in each direction is different for each rotor, the linear blades of each rotor are attached to one common rotating shaft, and the rotors adjacent to each other in the direction in which the rotating shaft extends are And is integrated by a ring-shaped end plate that connects the straight blades of one rotor and the straight blades of the other rotor.

  In the straight blade vertical axis wind turbine according to the present invention, the ring-shaped end plates are respectively attached to the blade ends on the terminal end side of the straight blades of the rotors located at both ends in the extending direction of the rotating shaft. preferable.

  In the straight blade vertical axis wind turbine according to the present invention, a plurality of rotors are supported by one common rotating shaft, and adjacent rotors are integrated by a ring-shaped end plate, and substantially all the rotors are one. Since the rotor is formed, a complicated mechanism for connecting or supporting a plurality of rotors, for example, a frame between the rotors, a support column for enhancing structural strength, or the like is not required. For this reason, the structure of the straight blade vertical axis wind turbine is simplified. Further, since the attachment positions of the straight blades in the circumferential direction of the rotation axis are different for each rotor, the wind turbine efficiency and startability (self-startability) are good.

  Hereinafter, embodiments of the present invention (best mode for carrying out the invention) will be described in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing a configuration of a straight blade vertical axis wind turbine in which two rotors are coupled by a ring-shaped end plate according to an embodiment of the present invention. 2 (a) and 2 (b) are a plan view and a front view of a wind turbine generator using the straight blade vertical axis wind turbine shown in FIG. 1, respectively.

As shown in FIGS. 1 and 2 (a) and 2 (b), in this straight blade vertical axis windmill W (hereinafter referred to as "windmill W") or a wind power generator, three upper straight blades 1a are used. Are respectively attached to the rotary shaft 3 via the upper arm 2a. Further, three lower straight blades 1b are attached to the rotary shaft 3 via lower arms 2b. Here, the rotating shaft 3 is rotatably supported by the rotating shaft support 4. The rotating shaft 3 passes through the rotating shaft column 4 and is connected to the power generation unit 6, and rotates a rotor (not shown) in the power generation unit 6 to generate electric power. The power generation unit 6 is supported by the device support 7.

  In the wind turbine W, the upper straight blade 1a and the upper arm 2a form an upper rotor 10a, and the lower straight blade 1b and the lower arm 2b form a lower rotor 10b. That is, the wind turbine W is basically a three-blade two-stage linear blade vertical axis wind turbine in which an upper rotor 10a and a lower rotor 10b that are adjacent to each other in the direction in which the rotating shaft 3 extends are arranged in two stages. It is.

  A ring-shaped end plate 5a is attached to the upper wing tip (end side) of the upper straight wing 1a using a fastener such as a screw. Similarly, a ring-shaped end plate 5b is also attached to the lower (terminal side) blade tip of the lower straight blade 1b using a fastener. Further, a ring-shaped end plate 5c is disposed between the upper rotor 10a and the lower rotor 10b. Here, the ring-shaped end plate 5c is connected to or coupled to the lower blade tip of the upper straight blade 1a and is connected to or coupled to the upper blade tip of the lower straight blade 1b by using a fastener such as a screw. Has been. In other words, the upper rotor 10a and the lower rotor 10b are integrated by the ring-shaped end plate 5c. In addition, you may adhere | attach each linear blade 1a, 1b and each ring-shaped end plate 5a, 5b, 5c with an adhesive agent.

  Thus, in the windmill W, since the upper rotor 10a and the lower rotor 10b are attached to one common rotating shaft 3 and integrated by the ring-shaped end plate 5c, they rotate together (synchronously rotate). . Therefore, it can be said that the upper rotor 10a and the lower rotor 10b substantially form or constitute one rotor.

  In the upper rotor 10a, the three upper straight blades 1a and the three upper arms 2a are arranged at equal angular intervals at positions that are 120 degrees apart from the center angle with respect to the rotation axis center in the positional relationship in the circumferential direction of the rotation axis. Yes. Each upper arm 2a extends radially in the horizontal direction with respect to the rotary shaft 3, and connects the upper linear blade 1a and the rotary shaft 3 extending in the vertical direction to support the upper rotor 10a. . In the lower rotor 10b as well, basically, as in the case of the upper rotor 10a, the three lower straight blades 1b and the three lower arms 2b are arranged at equiangular intervals at positions that are 120 degrees apart from each other. 2b supports the lower rotor 10b by connecting the lower linear blade 1b extending in the vertical direction and the rotary shaft 3 to each other.

  However, in the upper rotor 10a and the lower rotor 10b, the phases of the attachment positions in the circumferential direction of the rotation axis of the linear blades 1a, 1b and the arms 2a, 2b (center angle with respect to the rotation axis center) are shifted from each other by 60 degrees. That is, when the three upper straight blades 1a are located at the center angles of 0 degrees, 120 degrees, and 240 degrees in the upper rotor 10a, the three lower straight blades 1b are disposed at the center angles of 60 degrees, 180 degrees, and 300 in the lower rotor 10b. Will be in the position of degrees. Therefore, when the upper rotor 10a and the lower rotor 10b are integrated with the ring-shaped end plate 5c, the upper straight blades 1a and the lower straight blades 1b are alternately turned at a central angle of 60 degrees with respect to the rotation axis center. What is necessary is just to attach to the ring-shaped end plate 5c by shifting each other and reversing the positional relationship between the top and bottom.

  Thus, in the windmill W or the wind power generator according to the embodiment of the present invention, the upper rotor 10a and the lower rotor 10b are supported by one common rotating shaft 3 and integrated by the ring-shaped end plate 5c. Therefore, a complicated mechanism for connecting or supporting the rotors 10a and 10b, for example, a frame between the rotors required in the vertical axis wind power generator according to Patent Document 1, and a column for strengthening structural strength Etc. are not required. For this reason, the structure of the windmill W or the wind power generator is simplified. Further, since the upper rotor 10a and the lower rotor 10b have different attachment positions in the circumferential direction of the rotation axis of the straight blades 1a and 1b, the wind turbine efficiency and the startability (self-startability) are good.

Hereinafter, the function or performance of the wind turbine W according to the embodiment of the present invention will be described.
FIG. 3 is a graph showing the static torque of the three-blade two-stage wind turbine W shown in FIG. 1 with respect to the rotor azimuth, and also shows the average static torque. As shown in FIG. 3, the static torque of the windmill W shown in FIG. 1 is smoothed similarly to the static torque of the conventional six-blade one-stage windmill W2 shown in FIG. Therefore, the windmill W according to the embodiment is not easily affected by fluctuations in the wind direction. The average static torque of the wind turbine W according to the embodiment is 0.090 Nm, which is larger than the average static torque (0.084 Nm) of the conventional three-blade one-stage wind turbine W 1 shown in FIG. Therefore, it can be said that the startability of the windmill W according to the embodiment is good.

  4 shows a three-blade two-stage wind turbine W shown in FIG. 1, a conventional three-blade one-stage wind turbine W1 shown in FIG. 7, and a conventional one shown in FIG. 9 under a wind speed of 6 m / s. It is a graph which shows the result of having compared the output characteristic about the 6-blade 1-stage type windmill W2. The three-blade two-stage wind turbine W according to the embodiment of the present invention has a slightly lower wind turbine efficiency than the conventional three-blade one-stage wind turbine W1, but the conventional six-blade one-stage wind turbine W1. It can be seen that the wind turbine efficiency is very high compared to W2.

  As described above, in the wind turbine W according to the embodiment of the present invention, the ring-shaped end plate 5a is attached to the upper blade tip of the upper straight blade 1a, while the ring-shaped end is mounted on the lower blade tip of the lower straight blade 1b. Although the plate 5b is attached, these ring-shaped end plates 5a and 5b reduce the tip loss of both the straight blades 1a and 1b and increase the structural strength of the rotors 10a and 10b. In the following, the functions, functions, and effects of these ring-shaped end plates 5a and 5b will be described.

  Unlike the drag type Savonius wind turbine or the like, the conventional three-blade one-stage wind turbine W1 shown in FIG. 6 mainly generates a rotational force. However, in general, vortices are released from the tip of the straight blade 101, which reduces lift and causes tip loss.

FIG. 5 is a graph showing the calculation results of the output characteristics of the conventional three-blade one-stage wind turbine W1 shown in FIG. 6 with and without the blade tip loss based on the blade element momentum theory. is there. The calculation conditions are as follows.
(Calculation condition)
Number of blades: 3 Rotor radius: 0.4m
Height: 1.25m
Wind receiving area: 1m ²
Chord length: 0.24m
Solidity: 1.8 (number of blades x chord length / rotor radius)

  As shown in FIG. 5, when the peripheral speed ratio at which the output coefficient is substantially maximum is 1.25, a tip loss of about 5% occurs. However, if the same ring-shaped end plates 5a and 5b as in the case of the windmill W shown in FIG. 1 are attached to the conventional three-blade one-stage windmill W1 shown in FIG. Wind turbine efficiency can be increased.

It is a perspective view which shows the structure of the linear blade | wing vertical axis windmill which couple | bonded two rotors based on embodiment of this invention with the ring-shaped end plate. (A) And (b) is the top view and front view of a wind power generator which respectively used the linear blade | wing vertical axis windmill shown in FIG. 2 is a graph showing the static torque of the three-blade two-stage linear blade vertical axis wind turbine shown in FIG. 1 with respect to the rotor azimuth, and also shows the average static torque. Comparison of output characteristics between a three-blade two-stage straight-blade vertical-axis wind turbine according to an embodiment of the present invention and a conventional three-blade one-stage and six-blade one-stage straight-blade vertical-axis wind turbine It is a graph which shows the result. It is a graph which shows the result of having calculated the output characteristic of the conventional three-blade one-stage type linear blade vertical axis wind turbine shown in FIG. 6 with and without a blade tip loss. It is a perspective view of the conventional three-blade one-stage linear blade vertical axis wind turbine. FIG. 7 is a graph showing the static torque of the straight blade vertical axis wind turbine shown in FIG. 6 with respect to the rotor azimuth angle, and also shows the average static torque. It is a perspective view of the conventional 6 blade 1 step type straight blade vertical axis wind turbine. FIG. 9 is a graph showing the static torque of the straight blade vertical axis wind turbine shown in FIG. 8 with respect to the rotor azimuth, and also shows the average static torque.

Explanation of symbols

  W Straight blade vertical axis wind turbine, 1a Upper straight blade (blade), 1b Lower straight blade (blade), 2a Upper arm, 2b Lower arm, 3 Rotating shaft, 4 Rotating shaft post (pole), 5a Ring-shaped end plate, 5b Ring-shaped end plate, 5c Ring-shaped end plate, 6 Power generation unit, 7 Device support (pole), 10a Upper rotor, 10b Lower rotor.

Claims (2)

In a linear blade vertical axis wind turbine in which a rotor having straight blades attached to a rotating shaft is arranged in a plurality of stages in the direction in which the rotating shaft extends, and the mounting positions of the straight blades in the circumferential direction of the rotating shaft are different for each rotor,
The straight blades of each rotor are attached to one common rotating shaft,
Rotors adjacent to each other in the direction in which the rotation axis extends are integrated by a ring-shaped end plate that is located between the two rotors and connects the straight blades of one rotor and the straight blades of the other rotor. Straight wing vertical axis windmill.   2. The straight blade vertical axis according to claim 1, wherein ring-shaped end plates are respectively attached to the blade ends on the terminal side of the straight blades of the rotors located at both ends in the direction in which the rotating shaft extends. Axial windmill.

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