JP2007309287A - Wind power generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wind power generator having a simple configuration and exhibiting high power generation efficiency. <P>SOLUTION: This wind power generator is provided with: a duct having a small diameter part with minimum inner diameter between a front end part and a rear end part and swollen inwardly; a cylindrical container supported by and fixed to a support column erected on an inside face of the duct, extended along a central axis of the duct and storing a rotating shaft and a power generator; and an impeller connected to the rotating shaft. The support column supports the cylindrical container in the rear side from the small diameter part of the duct, and a blade of the impeller is provided in a position in the rear side from the support column and within the duct rear end part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wind turbine generator.

  A wind power generator is a device that rotates an impeller by wind and converts the rotational energy into electric energy by a generator to generate electric power. In order to increase the power generation efficiency of the wind turbine generator, it is common to increase the diameter of the impeller so that a large torque is generated in the impeller by the wind. However, since the wind turbine generator becomes large when the diameter of the impeller is increased, it takes time to manufacture, transport, and install it.

  In order to solve such a problem, a wind turbine generator having a configuration in which a cylindrical duct is arranged around an impeller has been developed. In such a wind power generator, the shape of the duct is devised (the inner diameter of the duct is enlarged or reduced along its length direction), so that the wind flowing into the duct is accelerated and brought into contact with the impeller. Therefore, it is possible to reduce the size of the apparatus.

Patent Literature 1 discloses a wind power generator in which a wind passage (air channel) is formed in a wall of a duct (shroud) from a front end portion or an outer surface of the duct to an inner surface behind the duct. Yes. And by forming such a wind passage, it is said that peeling at the duct rear part (diffuser section) of the wind flowing inside the duct, which causes a decrease in the performance of the wind turbine generator, can be prevented. Yes. In addition, it is desirable that this wind turbine generator is provided with a column (stator blade) that supports and fixes a container for housing the generator in front of the blade (rotor blade) of the impeller. ing. In addition, the blade | wing of the impeller of this wind power generator is arrange | positioned in the position (throat) where the internal diameter inside a duct becomes the minimum.
British Patent Application No. 1508752

  As described above, the wind power generator disclosed in Patent Document 1 prevents wind separation at the duct rear portion, which causes the performance of the device to be degraded, by the wind passage formed in the wall of the duct. However, since this wind power generator needs to form a wind passage inside the wall of the duct, its configuration is complicated and it takes time to manufacture.

  An object of the present invention is to provide a wind turbine generator having a simple configuration and high power generation efficiency.

  The present invention relates to a duct bulged inward having a small-diameter portion having a minimum inner diameter between a front end portion and a rear end portion, and a central axis of the duct that is supported and fixed to a support column erected on the inner surface of the duct. A wind turbine generator that includes a cylindrical container that accommodates the rotating shaft and the generator, and an impeller connected to the rotating shaft, wherein the support column is located behind the small-diameter portion of the duct. The wind turbine generator is characterized in that the cylindrical container is supported, and the blades of the impeller are provided at a position behind the column and not beyond the rear end of the duct.

The preferable aspect of the wind power generator of this invention is as follows.
(1) The opening diameter (Df) at the front end portion of the duct, the inner diameter (Dm) of the small diameter portion, and the opening diameter (De) at the rear end portion satisfy the following formulas (I) and (II).
(I) Df / Dm = 1.4-2.6
(II) De / Dm = 1.1 to 1.6
(2) Df / Dm is in the range of 1.8 to 2.3, and De / Dm is in the range of 1.2 to 1.4.
(3) The distance from the small diameter part of the duct to the support column is 10% or more of the distance from the small diameter part of the duct to the rear end part.
(4) The inner surface of the duct is streamlined.

  The wind power generator of the present invention increases the speed of the wind that has flowed into the duct in the region from the front end of the duct to the small diameter portion, and generates power by rotating the impeller with the increased wind.

  In the wind power generator of the present invention, the arrangement inside the duct of the supporting column and impeller blades supporting and fixing the cylindrical container in which the generator is accommodated is devised, and the wind flowing into the duct is ducted. It can be used for power generation after increasing to a sufficiently high speed in the region between the front end and the small diameter part, and the wind used for power generation (the wind that passed through the impeller) is moved outside the duct. High power generation efficiency (high output power) is exhibited because it can be quickly discharged and a large amount of wind can flow into the duct to increase speed.

  In addition, the wind power generator of the present invention can be configured by arranging the above-mentioned struts and blades at predetermined positions inside the duct, and it is not necessary to form a gas passage inside the wall of the duct. The structure is simple and easy to manufacture.

  A wind power generator according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a front view showing a configuration example of a wind turbine generator according to the present invention, and FIG. 2 is a portion of a wind turbine generator 10 in which a duct 14 is cut along a cut line II-II written in FIG. It is sectional drawing.

  A wind turbine generator 10 shown in FIGS. 1 and 2 is erected on an inner surface of a duct 14 that has a small-diameter portion 13 having a minimum inner diameter between a front end portion 11 and a rear end portion 12, and an inner surface of the duct 14. A cylindrical container 19 that accommodates a rotating shaft 17 and a generator 18 that extends along a central axis 16 of a duct (a cross section forms an airfoil) 14 that is supported and fixed to the support column 15, and a rotating shaft 17. It is comprised from the impeller 20 connected to.

  In the wind power generator 10, the wind flowing into the duct 14 is accelerated because the inner diameter of the duct is gradually reduced from the front end portion 11 to the small diameter portion 13, and the impeller 20 is rotated by the increased wind. Generate electricity. Further, since the inner diameter of the duct 14 is gradually enlarged from the small diameter portion 13 to the rear end portion 12, the air pressure decreases at the rear side of the small diameter portion 13 of the duct, and a larger amount of wind flows into the duct and increases. Speed up.

  And in the wind power generator 10 of this invention, the support | pillar 15 is supporting the cylindrical container 19 in the back side rather than the small diameter part 13 of a duct, and the blade | wing 21 of the impeller 20 is a back side rather than the support | pillar 15. And it is provided in the position which does not exceed the duct rear end part 12. Thus, by arrange | positioning the support | pillar 15 and the blade | wing 21 of the impeller 20, the electric power generation efficiency of a wind power generator can be made high. The reason is understood as follows.

  For example, as represented by the wind power generator disclosed in Patent Document 1, in order to obtain high power generation efficiency, in the conventional wind power generator, the blades of the impeller are in a state where the duct is a single unit (the blades inside the duct). Generally, it is arranged in the small diameter portion of the duct where the wind speed is maximum in a state where no car or the like is arranged.

  However, if the impeller blades are arranged in the small diameter portion of the duct, the impeller blades become a resistance (obstacle) to the wind flowing into the duct, and the wind speed in the small diameter portion is reduced (disposed in the small diameter portion). As the wind approaches the blade, the wind will not be able to increase sufficiently). For this reason, the wind speed inside a duct becomes the maximum in the front side rather than a small diameter part (position where the blade | wing is arrange | positioned). The maximum value of the wind speed on the front side of this small-diameter portion is that the wind flowing into the duct does not reach the small-diameter portion (not sufficiently increased), so the wind speed value of the small-diameter portion in the state of the duct alone Indicates a smaller value. As described above, the impeller disposed in the small-diameter portion of the duct (or the front side of the small-diameter portion) becomes a cause of hindering the acceleration of the wind flowing into the duct. Similarly, a support column that supports and fixes a cylindrical container that houses a generator or the like also causes an increase in the speed of wind flowing into the duct.

  And in the wind power generator 10 of this invention, both the support | pillar 15 used as the resistance with respect to the wind which flowed into the duct 14, and the blade | wing 21 of the impeller 20 are arrange | positioned rather than the small diameter part 13 of the duct 14. In particular, since the blade 21 of the impeller 20 having a relatively high resistance to wind is not disposed in the small diameter portion 13 of the duct 14 but is disposed further rearward than the small diameter portion 13, The wind that has flowed in is increased to a sufficiently high speed before reaching the small diameter portion 13 from the front end portion 11.

  On the other hand, even if the wind that has flowed into the duct 14 is increased to a sufficiently high speed before reaching the small diameter portion 13, the inner diameter of the duct is reduced from the small diameter portion 13 to the rear end portion. Since the speed is gradually increased toward 12, the blade 21 of the impeller 20 is disposed on the rear side of the small diameter portion 13 of the duct, and it is difficult to obtain high power generation efficiency.

  However, the wind that has passed through the small-diameter portion 13 of the duct 14 tends to flow backward along the inner surface of the duct. That is, the wind flowing from the small-diameter portion 13 to the rear side in the duct 14 is not uniformly decelerated, but is not effectively used for power generation that flows in the rear side near the central axis 16 of the duct 14 (of the blades 21). Wind that contacts the base side and does not generate sufficient torque at the impeller 20 is greatly decelerated, whereas wind (blade) that is effectively used for power generation that flows backward near the inner surface of the duct 14. The wind that comes into contact with the tip end portion 21 and generates a large torque at the impeller 20 is relatively difficult to decelerate.

  For this reason, in the wind turbine generator 10 of the present invention, the vane 21 of the impeller 20 is arranged on the rear side of the small-diameter portion 13 of the duct 14, but on the tip portion side of the vane 21 (in the small-diameter portion 13 Although the speed is slightly lower than the wind speed, power generation can be performed with high efficiency because of relatively high-speed wind contact.

  Further, when the blade 21 of the impeller 20 is disposed on the rear side of the small-diameter portion 13 of the duct 14, an impeller having a large diameter capable of generating a larger torque can be used. It becomes possible to efficiently convert the energy of the flowing wind into electric energy.

  Further, in the wind turbine generator 10 of the present invention, the blades 21 of the impeller 20 are arranged on the rear side of the support column 15, and therefore, in an oblique direction with respect to the central axis 16 of the duct 14 after passing through the impeller. The advancing wind does not contact the support column 15, thereby preventing the wind flow from being disturbed on the rear side of the impeller inside the duct (eg, generating a wind vortex). Therefore, the wind that has passed through the impeller 20 is quickly discharged from the rear end portion 12 of the duct 14 to the outside, and an increase in air pressure on the rear side of the impeller inside the duct can be suppressed. Compared with the case where it is arranged on the front side, a larger amount of wind can flow into the duct to increase the speed.

  That is, the wind power generator 10 of the present invention is used for power generation after increasing the wind flowing into the duct 14 to a sufficiently high speed in the region between the front end portion 11 and the small diameter portion 13 of the duct 14. High power generation efficiency (high output power) in order to quickly discharge the wind used for power generation (the wind that has passed through the impeller) to the outside of the duct and to increase the speed of the wind through the duct. Indicates.

  In addition, the wind power generator 10 of the present invention can be configured by arranging the struts 15 and the blades 21 of the impeller 20 at the predetermined positions inside the duct 14, and gas inside the duct wall body. Since it is not necessary to form a passage, the structure is simple and the manufacture is easy.

As shown in FIG. 2, the distance L ₁ from the small-diameter portion 13 of the duct to the column 15 is preferably 10% or more of the distance L ₂ from the small-diameter portion 13 to the rear end portion 12 of the duct. As a result, the support column 15 and the blades 21 of the impeller 20 that are likely to hinder the speed increase of the wind that has flowed into the duct 14 are disposed sufficiently rearward inside the duct. This is because it is possible to sufficiently increase the wind speed increase rate in the region between the two.

  In addition, since the cylindrical container 19 is normally set in the shape which shows low resistance with respect to the wind which flows in into the duct 14, the front end part side of the container 19 is arrange | positioned ahead of the small diameter part 13 of a duct. However, as shown in FIG. 2, the front end portion of the container 19 is also preferably arranged on the rear side of the small diameter portion 13 of the duct. As this cylindrical container 19, the case of the main body of the generator 18 can also be used. When the generator 18 is accommodated inside the cylindrical container 19 as described above, maintenance and replacement when the generator fails are easy.

In the wind turbine generator of the present invention, it is preferable that the opening diameter Df at the front end of the duct, the inner diameter Dm of the small diameter portion, and the opening diameter De at the rear end satisfy the following formulas (I) and (II). .
(I) Df / Dm = 1.4-2.6
(II) De / Dm = 1.1 to 1.6

  This is because if the value of Df / Dm is less than 1.4, it is difficult for the wind flowing into the duct 14 to increase in the region between the front end portion 11 and the small diameter portion 13 of the duct, If the value of Dm exceeds 2.6, the side of the front end of the duct expands to a wide angle, the resistance to the wind at the front end 11 of the duct and its vicinity increases, and the wind flows from the front end of the duct. This is because it becomes difficult (a part of the wind flows outside the duct).

  On the other hand, if the value of De / Dm is less than 1.1, the atmospheric pressure rises on the rear side of the small-diameter portion 13 of the duct 14 and it becomes difficult for the wind to flow from the front end portion 11 of the duct. On the other hand, when the value of De / Dm exceeds 1.6, the wind flowing from the small diameter portion 13 of the duct 14 to the rear end portion 12 is peeled off from the inner surface of the duct, thereby disturbing the flow of the wind. The speed of the wind coming into contact with the 20 blades 21 is reduced, so that the output power is reduced or the output power is unstable.

  It is particularly preferable that the value of Df / Dm is in the range of 1.8 to 2.3, and the value of De / Dm is in the range of 1.2 to 1.4. A duct with a shape that satisfies this condition has a high wind speed increase rate in the region between the front end and the rear end of the duct, and the pressure rises behind the small diameter portion of the duct and the wind from the inner surface of the duct. This is because the wind power generation apparatus exhibits extremely high power generation efficiency because the peeling of the wind power is effectively suppressed.

  In order to make the flow of the wind inside the duct 14 smooth, the inner surface of the duct is preferably streamlined. Further, as shown in FIG. 2, the duct 14 is preferably set in a shape like an airfoil having a rounded front end portion 11 of the wall cross section and showing a low resistance to wind.

  Moreover, as shown in FIG.1 and FIG.2, in the wind power generator 10, from the outer surface of the duct provided along the circumference | surroundings of the duct in the outer surface behind the center of the length direction of the duct 14 A skirt 31 having an inclined surface 31a extending to the rear outer side of the duct, and a surface connected to the inclined surface 31a of the hem 31 and extending to the outer side of the duct with an angle β larger than an inclination angle α with respect to the duct central axis 16 of the inclined surface 31a. It is preferable that an annular wind direction adjuster 30 comprising an edge 32 having 32a is provided.

  The wind direction adjuster 30 causes the direction of the wind toward the rear side along the outer surface of the duct 14 to gradually move toward the outside in the radial direction of the duct at the skirt portion 31, and then suddenly at the edge portion 32. Adjust to go radially outward. Thereby, a space region (hereinafter also referred to as a decompression region) having a low air pressure is generated on the rear side of the duct 14 and the edge portion 32 and further on the rear side of the radially outer region of the edge portion 32. By generating such a reduced pressure region, a larger amount of wind can flow from the front end portion 11 of the duct 14 to increase the speed.

  If the wind direction adjuster is not provided with a skirt, the wind contacts at an angle close to the edge, so that a space area with low air pressure is generated on the rear side of the duct and the edge. Since the air pressure on the rear side of the radially outer region of the edge portion does not greatly decrease, the amount of wind flowing from the front end portion of the duct is smaller than in the case of the air direction adjuster 30 having the skirt portion 31 described above.

  The inclination angle α of the inclined surface 31a of the skirt 31 is preferably in the range of 20 to 30 degrees. When the inclination angle α is less than 20 degrees, it becomes difficult to generate a low atmospheric pressure space region on the rear side of the radially outer region of the edge, and when the inclination angle α exceeds 30 degrees, This is because the size (that is, the outer diameter of the edge portion 32) becomes large, and it becomes difficult to handle the wind power generator 10 or to carry it by a vehicle.

  Moreover, it is preferable that the edge part 32 is provided in the rear-end part 12 of the duct 14 because the manufacture becomes easy. The outer diameter of the edge 32 is preferably in the range of 115 to 145% of the opening diameter Df at the front end 11 of the duct 14. This is because if the outer diameter of the edge portion 32 is too small, it is difficult to generate the above-described reduced pressure region, and if the diameter is too large, it is difficult to handle the wind power generator 10 as described above. In order to make it easy to generate the reduced pressure region, the inclination angle β of the surface 32a of the edge 32 with respect to the duct center axis 16 is preferably in the range of 80 to 100 degrees.

It is preferable that the length L ₃ along the central axis direction of the duct of the air direction adjusting tool 30 is in the range of 5 to 25% of the length L ₀ of the duct in the central axis direction. If the length of the wind direction adjuster is too short, it is difficult to generate the above-described reduced pressure region, and if the length is too long, the size of the wind direction adjuster becomes too large, making it difficult to handle the wind power generator 10 as described above. Because it becomes.

  As described above, since the wind power generation apparatus of the present invention has high power generation efficiency, sufficiently high output power can be obtained even with low-speed wind, and the apparatus can be easily downsized. For this reason, the wind power generator of the present invention can be installed on a wall surface or a rooftop of a building such as a mountainous area or a building, which has conventionally been difficult to transport and install the wind power generator.

  First, a frame having substantially the same shape as the duct was prepared, and an FRP (glass fiber reinforced polyester resin) sheet was attached to the inside and outside thereof, thereby producing the duct 14 shown in FIGS.

The opening diameter Df at the front end portion of the duct 14 is 2075 mm, the inner diameter Dm of the small diameter portion is 1037 mm, and the opening diameter De at the rear end portion is 1352 mm, that is, the value of Df / Dm of the duct is 2.0. And the value of De / Dm was set to 1.3. The total length L ₀ of the duct was set to 3614 mm, and the distance L ₂ from the small diameter portion 13 to the rear end portion 12 was set to 2176 mm.

Further, the length L ₃ along the central axis direction of the duct 14 of the wind direction adjusting tool 30 was set to 482 mm, that is, 13% of the length L ₀ of the duct in the central axis direction. The inclination angle α of the slope 31a of the skirt 31 of the wind direction adjusting tool 30 was set to 25 degrees, and the inclination angle β of the surface 32a of the edge 32 was set to 90 degrees. The outer diameter Ds of the edge portion 32 was set to 2700 mm, that is, the length of 130% of the opening diameter Df at the front end portion 11 of the duct 14.

Next, a generator (synchronous three-phase AC generator) 18 and a rotating shaft 17 are accommodated in the cylindrical container 19, and an impeller 20 having a diameter (FIG. 1: Dp) of 1130 mm is accommodated in the rotating shaft 17. Attached. This cylindrical container was fixed to the inner surface of the duct using four support columns 15. At this time, the distance L ₁ from the small-diameter portion 13 of the duct to the support column 15 was set to 431 mm, that is, 20% of the distance from the small-diameter portion 13 to the rear end portion 12 of the duct.

  Thus, the wind power generator 10 shown in FIG. 1 was produced. The output power of the generator 18 is taken out through the electric wiring 33 embedded in the support column 15 and the duct 14.

  When wind with a wind speed of 10.5 m / sec was passed from the front side of the duct of the produced wind power generator 10, the output power of the generator 18 was 4330W. In addition, a commercial wind turbine generator having a duct around the impeller (diameter 1200 mm) (the impeller is disposed in the small diameter portion of the duct, and the cylindrical container is fixed to the inner surface of the duct by the support column at the rear side thereof. Even if the wind speed is 12 m / sec, the output power is about 1200 to 1500 W, and it can be seen that the power generation efficiency of the wind power generator of the present invention is extremely high.

It is a front view which shows the structural example of the wind power generator of this invention. It is a fragmentary sectional view of the wind power generator 10 which cut | disconnected the duct 14 along the cutting line II-II line entered in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Wind power generator 11 Front end part 12 Rear end part 13 Small diameter part 14 Duct 15 Support | pillar 16 Central axis 17 Rotating shaft 18 Generator 19 Cylindrical container 20 Impeller 21 Blade 30 Wind direction adjustment tool 31 Bottom part 31a Slope of bottom part 32 Edge Part 32a Edge surface 33 Electric wiring

Claims (5)

  A duct that bulges inward with a small-diameter portion having the smallest inner diameter between the front end portion and the rear end portion, and extends along the central axis of the duct that is supported and fixed to a support column erected on the inner surface of the duct. A wind turbine generator including a cylindrical container for accommodating a rotating shaft and a generator, and an impeller connected to the rotating shaft, wherein the column is disposed on the rear side of the small diameter portion of the duct. And the blade of the impeller is provided at a position behind the support column and not exceeding the rear end of the duct. The opening diameter (Df) at the front end portion of the duct, the inner diameter (Dm) of the small diameter portion, and the opening diameter (De) at the rear end portion satisfy the following formulas (I) and (II). Wind power generator:
(I) Df / Dm = 1.4-2.6
(II) De / Dm = 1.1-1.6.   The wind power generator according to claim 2, wherein Df / Dm is in a range of 1.8 to 2.3 and De / Dm is in a range of 1.2 to 1.4.   The wind turbine generator according to any one of claims 1 to 3, wherein a distance from the small diameter portion of the duct to the support column is 10% or more of a distance from the small diameter portion of the duct to the rear end portion.   The wind power generator according to any one of claims 1 to 4, wherein an inner surface of the duct is streamlined.

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