JP2013113285A - Wind power generation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sail-type wind turbine capable of controlling a blade angle almost without being affected by a centrifugal force with rotation of the wind turbine.SOLUTION: A wind power generation apparatus includes: a plurality of rods 4 that extend radially from a hollow rotary shaft 3; a blade 5 that is fixed between adjoining rods 4 and has a leading edge 5a which is fixed to an adjoining rod 4 positioned on a front side in a rotational direction in a manner of variable relative angle; a coil spring that is disposed in a hollow portion of the rotary shaft 3 and elongates and contracts in a shaft length direction of the rotational direction; and a rope one end of which is fixed to a trailing edge 5b of the blade 5, which is then suspended over the rod 4 on a back side in the rotational direction and is guided in the rotary shaft 3, and the other end of which is connected with a free end of the coil spring.

Description

The present invention relates to a wind turbine generator that converts wind energy into rotational power.

Propeller type windmills operate efficiently in places where the average wind speed is 3 meters per second or more, but there are not many places in Japan. On the other hand, since the sail type windmill operates even in a relatively light wind place where the average wind speed is less than 3 meters per second, there are more places where it can be installed.
The wind turbine always generates stable rotational power in a wide range of wind speeds from weak winds to strong winds and prevents damage to the wind turbine components by preventing excessive force from being applied to the components of the wind turbine. Therefore, a mechanism for changing the blade angle (pitch angle) is provided.

Although the wind turbine disclosed in Patent Document 1 is a propeller type wind turbine, it has a spring that expands and contracts in the axial direction of the rotating shaft, and presses the cam against this to give elasticity to the rotation of the cam to What adjusts a rotation angle is disclosed. However, because it is a propeller type, it cannot be used in windy areas.
In the wind turbines disclosed in Patent Documents 2 and 3, the blades of the sail type wind turbine are supported by the blade elastic body, and when the wind becomes strong, the elastic body is stretched to change the blade angle. However, if the windmill rotates faster, the elastic body itself is driven out to the outer peripheral side by centrifugal force, and the accuracy of blade angle control is impaired.

JP 2011-106272 A JP 2010-265823 A JP 2011-47291 A

In the sail type windmill, as shown in Patent Documents 2 and 3, the blade angle is changed by changing the distance between the trailing edge of the blade and the blade shaft adjacent thereto. As the blade angle increases, the trailing edge of the blade increases in distance from the blade axis adjacent to the blade. Therefore, the expansion / contraction length of the elastic body must correspond to this. For example, if the length of one side of the outer peripheral side of the blade is 1 meter, a minimum of 1.4 meters (1 × √) is allowed to allow a blade angle of 90 degrees (the blade is parallel to the wind direction). A coil spring having a stretchable length of 2) is required. If a coil spring having a free length comparable to the extension / contraction length is used, a length of about 3 meters, which is about twice this 1.4 meter, must be secured for the coil spring and its extension / contraction.

On the other hand, if a long coil spring is used, a long expansion / contraction length can be accommodated. However, if a long coil spring is installed between the trailing edge of the blade and the blade shaft, the area of the blade is reduced. In addition, when the weight of the coil spring increases and the windmill rotates faster, the coil spring itself is driven out to the outer peripheral side by centrifugal force, and in the case of a sail type windmill, it cannot be actually installed. Further, even if the coil springs are arranged radially along the blade axis, the coil springs are driven out to the outer periphery by their own weight due to centrifugal force, and the accuracy of blade angle control is impaired.
An object of the present invention is to provide a sail-type windmill capable of controlling the blade angle without being substantially affected by the weight of the coil spring against the centrifugal force accompanying the rotation of the windmill.

The wind turbine generator according to the present invention is fixed between a plurality of rods projecting radially from a hollow rotating shaft and adjacent rods, and the front edge is fixed to the front rod in the rotational direction so that the relative angle can be changed. The wing body, a coil spring having an expansion / contraction range in the axial length direction of the rotation shaft in the hollow of the rotation shaft, the rear edge of the wing body is indexed, and is suspended on the rod on the rear side in the rotation direction. A rope guided in the rotating shaft and connected at the other end to the free end of the coil spring, and a generator having at least a hollow tube as a main shaft from the inlet to the back beyond the position where the rotor is fixed. The rotating shaft is inserted into the hollow of the main shaft of the generator, and the expansion / contraction range of the coil spring is a range including a position where the rotor is fixed.

According to the present invention, when there is no wind, it is close to the rod that is suspended, and when the wind becomes strong, the length between the trailing edge of the wing body and the rod that is away from the rod is supported with a long extension length. A long coil spring is accommodated in the main shaft in the generator, and the expansion and contraction direction of the coil spring is orthogonal to the direction of the centrifugal force acting by the rotation of the windmill. Therefore, a long coil spring can be used without opening between the wind turbine and the generator, and the expansion and contraction of the coil spring is hardly affected by the centrifugal force, and the blade angle can be accurately controlled.

It is a perspective view of a windmill. It is a perspective view which shows the coupling structure of a rod and a wing body. It is sectional drawing of a rotating shaft. It is a figure which shows the connection relation of a generator and a windmill. It is a perspective view which shows the other coupling structure of a rod and a wing body.

FIG. 1 shows a sail-type windmill 100 according to an embodiment and a wind power generator 200 using the same.
The windmill 100 includes a plurality of rods 4 projecting radially from the boss 15 and a wing body 5 deployed between the rods 4. The windmill 100 is connected to a generator 300 installed in the nacelle 2 on the support 1 to constitute a wind power generator 200. The nacelle 2 is controlled to turn on the column 1 by an azimuth control mechanism (not shown) so that the windmill 100 is always directed toward the windward b1.

The rod 4 is a hollow tube and projects radially from the outer periphery of the boss 15 (FIG. 2) located at the tip of the rotating shaft 3. The rotating shaft 3 extends through the generator 300 to the rear thereof. A plurality of rods 4 are provided, and there are eight rods in the illustrated example. The wing body 5 has a front edge 5a coupled to the rod 4 on the front side in the rotational direction b2.

FIG. 2 shows the wing body 5 deployed between the rods 4. The wing body 5 is formed of a blade 6 and a string-like member 7. The blades 6 are generally triangular, and circular holes c1, c2, and c3 for passing strings from the bosses 15 in the counterclockwise direction are formed at the apex portions of the blades 6, respectively. As the blade 6, a thin plate-like polycarbonate is used. This is because it is light and sticky and is difficult to break, and because it forms a wing shape by receiving wind, and weather resistance can also be expected.

The front edge 5 a of the wing body 5 includes a front side 6 a of the blade 6 and a string-like member 7. The front side 6a is formed in a cylindrical shape, and a string-like member 7 is passed through it. A strip member 8 having a C-shaped cross section is fixed to the outer peripheral surface of the rod 4 along the longitudinal direction thereof. The openings 8b are substantially the same as the thickness of the blade 6 and are fixed to the strip member 8 by inserting the front side 6a of the blade 6 into the strip member 8 from the opening 8a on the outer side. . Further, the string-like member 7 is inserted into and tied to the string passing members 9 a and 9 b on the original side (boss 15 side) of the rod 4 and the tip side of the rod 4 and the circular holes c 1 and c 2 of the blade 6. In this way, the leading edge 5 a of the wing body 5 is fixed to the rod 4. By receiving the wind pressure, the rope 10 moves as shown in addition to the twist of the string-like member 7 or the flexibility of the blade 6 itself, and the blade body 5 tilts backward with respect to the rod 4, so that the blade angle can have θ.

At the trailing edge 5 b of the wing body 5, one end of the rope 10 is stopped in the circular hole c <b> 3 at the rear of each wing body 5, thereby indexing the wing body 5. The rope 10 is suspended by the tip e1 of the rod 4 and guided into the hollow of the rod 4. A first sliding member 14a that reduces the frictional force associated with the feeding of the rope 10 is fixed to the tip e1 of the rod 4. The first sliding member 14a is a 90-degree bent cylindrical member, and is entirely formed of a material (for example, polytetrafluoroethylene) having a smaller friction coefficient than the material of the rod 4.

In FIG. 2, d1 indicates the rotating surface of the rod 4, and d2 indicates a state in which the wing body 5 is retracted to the leeward side. D3 shows a state in which the wind is strong and the wing body 5 is retracted to a wing angle of about 90 degrees. The blade angle θ is an angle formed by the blade body 5 and the rotating surface of the rod 4.
FIG. 3 shows a cross-sectional structure of the rotating shaft 3 including the boss 15 and the cylindrical shaft body 16 that follows the boss 15. The boss 15 is disposed concentrically on the front side of the shaft body 16 and includes two annular plates 15 a. Are connected together. A cover 15b is detachably mounted on the front end surface of the boss 15 via a bolt. The space inside the boss 15 communicates with the hollow of the rod 4, and the rope 10 that has reached the original side of the rod 4 is guided to the internal space of the boss 15.

The hollow of the shaft body 16 communicates with the inner space of the boss 15. The front end portion e <b> 2 of the shaft body 16 is positioned at the root position of the rod 4. The rope 10 that has reached the inside of the boss 15 through the hollow of each rod 4 is guided to the front end portion e2 of the shaft body 16, and then bent 90 degrees and guided to the hollow of the shaft body 16. The front end portion e2 guides the rope 10 in a bent shape, and a second sliding member 14b for reducing the frictional force accompanying the sliding of the rope 10 is fixed. The second sliding member 14b has an arcuate cross-sectional shape on the outer surface of the front half, and is entirely formed of a material having a smaller friction coefficient than that of metal (for example, polytetrafluoroethylene).

In the shaft body 16, the coil spring 12 which is an elastic body concentrically is disposed along the axial length. The rear end of the coil spring 12 is stopped at the back of the shaft body 16, and the front end (boss 15 side) is a free end.

A disc body 13 is fixed to the free end of the coil spring 12. Eight rope fastening holes g1 are concentrically formed in the disc body 13, and the other end of the rope 10 led to the free end side through the inside of the coil spring 12 is formed in each rope fastening hole g1. It is fastened. An annular protrusion f1 is formed in the hollow of the shaft body 16, and the disk body 13 comes into contact therewith. The expansion / contraction range H obtained by adding the free length and the expansion / contraction length of the coil spring is a range from the inner part of the shaft body 16 to the annular ridge f1, and the coil spring expands and contracts in the expansion / contraction range H. The position of the rope 10 is adjusted so that each rope 10 is in contact with the second sliding member 14b with a relatively small tensile force based on the elasticity of the coil spring 12 due to the initial compression even when the wing body 5 is not receiving wind. It is preferable for stabilization of

Since the wing body 5 has a long expansion / contraction length so that the wing angle may be 90 degrees, the length of the coil spring 12 is also increased, and the length of the shaft body 16 for accommodating the coil spring 12 is also increased. If the generator is arranged after the shaft body 16, the rotating shaft from the windmill 100 to the generator 300 becomes long. Therefore, in this embodiment, the main shaft 11 of the generator 300 is configured by a hollow tube. The space between the windmill 100 and the generator 300 is narrowed by inserting the shaft body 16 therein.

FIG. 4 shows how the generator 300 is connected to the boss 15 and the shaft body 16. The generator 300 may be any generator, but the main shaft 11 is at least hollow in a range extending from the tip 11a to the back beyond the position 301a where the rotor 301 is fixed (in the embodiment, the main shaft 11). Is a tube having a hollow through from the inlet to the outlet). A shaft body 16 is inserted and fixed to the main shaft 11 (FIG. 4B).

When the main shaft 11 is a hollow tube, the wind turbine 100 can be easily assembled. Further, when the shaft body 16 is disposed through the fixing position 301 a of the rotor 301, the expansion / contraction range H of the coil spring 12 and the shaft body 16 become a range including the position 301 a to which the rotor 301 is fixed. For this reason, a separate connecting shaft is not required to transmit the rotation. In the embodiment, the shaft body 16 penetrates the main shaft 11 and extends to the rear side of the generator 300.

As such a generator, for example, a generator disclosed in Japanese Patent Application No. 2011-236601 by the present applicant can be used. This generator is an axial gap type generator in which a plurality of permanent magnets 302 of the rotor 301 are arranged in the main axis direction. A stator pole 303 is arranged in the main axis direction, and the stator pole 303 is lengthened and wound. It is a generator whose length in the main axis direction is increased by increasing the dose. For this reason, the long coil spring 12 can be accommodated in the main shaft.

Next, the operation of the wind turbine according to this embodiment will be described.
Under a windless state, in this state, each rope 10 is only given a relatively small tensile force based on the elasticity of the initial tension of the coil spring 12, and each wing body 5 has a rear portion thereof that is the first by the rope 10. Since it is tension-suspended on the rod 4 at the position of the sliding member 14a, the blade angle θ is maintained in a deployed state where the blade angle θ is substantially zero as shown in FIG.

When the wind turbine receives wind, the nacelle 2 is turned so as to go upwind by the action of an azimuth control mechanism (not shown). Thereby, each wing body 5 always receives wind from the front, and each wing body 5 is given a force by which the rear portion is moved backward by the wind energy. This force is transmitted to the corresponding rope 10 and then transmitted to the coil spring 12 via the disc body 13. As a result, the coil spring 12 is elastically deformed, and each rope 10 is drawn out from the first sliding member 14a by this elastic deformation amount, and each blade body 5 increases the blade angle θ. The windmill 100 is rotated by wind energy and transmitted to the load device in the nacelle 2. At this time, centrifugal force acts on the coil spring 12, but since the direction of elastic deformation of the coil spring is perpendicular to the direction in which the centrifugal force acts, there is almost no influence on the elastic deformation of the coil spring 12.

Under such an operating state, when the wind energy received by the windmill increases, each blade body 5 further increases the blade angle θ to cause the wind energy to flow backward. Thereby, it is suppressed that the rotation speed of the windmill 100 increases too much. On the other hand, when the wind speed received by the windmill decreases and the energy decreases, each wing body 5 reduces the blade angle θ to promote the utilization of wind energy.

Since the rope 10 is lightweight, the magnitude of the centrifugal force generated is relatively small. On the other hand, the coil spring 12 expands and contracts in the axial length direction of the rotary shaft 3 and is different from the direction in which the centrifugal force acts. Therefore, even if the wind speed received by the windmill 100 increases, the control of the blade angle θ is stabilized without being affected by the centrifugal force.

Moreover, since the coil spring 12 and the disk body 13 are located concentrically on the inner side of the rotating shaft 3, the influence of centrifugal force due to the rotation of the rotating shaft 3 is suppressed. The coil spring 12 and the disk body 13 can be prevented from being exposed to wind and rain, and the blade angle control function can be well maintained over a long period of time. Further, since the rope 10 is coupled to the disk body 13 through the inside of the rod 4 and the inside of the rotary shaft 3, the rope 10 can be made difficult to interfere with the wing body 5.

A first sliding member 14a and a second sliding member 14b made of a material capable of reducing the frictional force are fixed to a portion of the rod 4 and the rotating shaft 3 that guides the rope 10 in a bent shape. By being received by the arcuate surfaces of the sliding members 14a and 14b, the sliding members 14a and 14b are deformed into a curved shape and slide. For this reason, noise can be reduced compared with the case where the rope 10 is guided by a pulley.

In the present embodiment, a polycarbonate plate is used as the wing body 5, but other types of plastic thin plates may be used. Alternatively, canvas may be used instead of polycarbonate. Further, the connection between the wing body 5 and the rod 4 is formed as shown in FIG. 5 by forming or sewing the sides of the blades 6 on the side of the circular holes c1 and c2 to form a cylindrical front edge 5a. You may make it pass the rod 4 in it. By doing so, the shape of the leading edge 5a is streamlined, so the air resistance is reduced.

Moreover, you may make it guide a wire rope by rotation of these guide wheels by making each of the 1st sliding material 14a and the 2nd sliding material 14b into a rotatable pulley.
Further, in the embodiment, the blade angle θ is increased by extending the coil spring 12, but the blade angle θ may be increased by compressing the coil spring 12. In this case, the front end of the coil spring 12 is received by the annular protrusion f1 of the shaft body 16, and the rear end is a free end. The disc body 13 is disposed so as to abut against the rear end of the coil spring 12. Although the point which fixes the other end of the rope 10 to the disc body 13 is the same as the previous Example, the rope 10 is arrange | positioned through the coil spring 12 toward the 2nd sliding material 14b. .

In this embodiment, the rod 4 is a hollow tube, but it need not be hollow. In this case, the rope 10 is arranged along the rod 4. However, in the embodiment of FIG. 5, for example, when the cylindrical front edge 5a of the wing body 5 located on the rear side in the rotational direction becomes a streamlined type, a space formed on the rear side of the rod 4 entering the cylinder. The rope 10 may be arranged in the 5c, and in this case, the circumference of the rope 10 can be surrounded by the cylindrical front edge 5a.
In this embodiment, the windmill 100 is disposed on the windward side of the generator 300, but may be disposed on the leeward side (downwind type).

In this embodiment, one coil spring 12 is used for eight ropes 10, but a plurality of coil springs are used to individually or several for each rope 10. A coil spring may be assigned. The blade angle θ varies depending on the position of each wing part 5, and it becomes possible to allow the degree of extension of the rope 10 to change.

3 Rotating shaft 4 Rod 5 Wing body 5a Leading edge 10 Rope 12 Coil spring 14a First sliding member 14b Second sliding member

Claims (1)

A plurality of rods projecting radially from a hollow rotating shaft;
A wing body between adjacent rods, the front edge of which is fixed to the rod on the front side in the rotational direction so that the relative angle can be changed;
A coil spring having a range of expansion and contraction in the axial direction of the rotary shaft within the hollow of the rotary shaft;
A rope indexing the rear edge of the wing body, suspended on the rod on the rear side in the rotation direction and guided in the rotation shaft, and having the other end connected to the free end of the coil spring;
A generator having at least a hollow tube as a main shaft from the entrance to the back beyond the position where the rotor is fixed,
The wind turbine generator according to claim 1, wherein the rotating shaft is inserted into a hollow of a main shaft of a generator, and an expansion / contraction range of the coil spring is a range including a position where the rotor is fixed.