WO2002064974A1

WO2002064974A1 - Wind power generating device

Info

Publication number: WO2002064974A1
Application number: PCT/JP2002/001122
Authority: WO
Inventors: Akira Obata
Original assignee: Akira Obata
Priority date: 2001-02-13
Filing date: 2002-02-12
Publication date: 2002-08-22
Also published as: JP3435540B2; JP2002242816A

Abstract

A wind power generating device, wherein a blade (1) having a torsionally flexible structure is installed at a boss part (7) so as to be moved freely only through a flap angle of β, and a control member utilizing a centrifugal force or an aerodynamic force is installed near the wing end of the blade (1), whereby, since the blade (1) is tilted to a downwind side in a wide flap angle range according to a wind velocity, the rotation of the blade can be controlled.

Description

Specification

Technical field of wind power generator

The present invention relates to a propeller-type wind power generator that rotates a rotor having a plurality of blades radially attached thereto.

Background art

In recent years, the use of clean renewable energy has been reconsidered, and a typical example is wind power, which is said to have the lowest energy cost. However, from the viewpoint of realizing the widespread use of wind power generation, drastic reduction of windmill manufacturing and assembly costs is required.

A variable pitch angle device is attached to the blade root of the conventional propeller type wind power generator to prevent over-rotation against strong winds. There was a problem that not only the centrifugal force due to the rotation of the plate but also a large bending load due to gusts and the like acts on the joint portion with the boss. It is necessary to increase the strength while reducing the weight by implementing a design that takes care of the fine grain of the wood.

However, this was also the reason why a radically simple and inexpensive blade was not allowed.

In addition, a device that 'changes the pitch angle' of a board with an appropriate mass must necessarily have high strength and high accuracy, which also increases the weight and cost of the wind turbine generator This was a major factor.

Thus, conventional propeller-type wind turbines must be equipped with high-strength and precise pitch angle variable devices, Since the cables had to withstand large bending loads and centrifugal loads, there was a problem that not only manufacturing costs but also transportation and assembly costs became large.

The present invention solves the above-mentioned problems. By making the blade portion of the wind turbine generator flexible, a lightweight and simple structure is made possible, and the costs involved in manufacturing, transporting, and assembling the device are reduced. The aim is to significantly reduce Disclosure of the invention

In order to solve the above-mentioned problems, the present inventor attaches a flexible blade to a boss portion so as to be freely rotatable only in the direction of the flap angle, that is, in the direction of the upper and lower surfaces of the blade, and near the blade tip. By installing a control member that uses centrifugal force or pneumatic force to the surface, it does not require conventional rigid blades or a pitch angle control device, and it can exceed the rating by changing the flap angle. It was found that overspeed due to the wind speed could be prevented. According to the wind power generator of the present invention, the skeleton of the invention of claim 1 forms a frame, and as shown in Fig. 2, the span of the rotor boss in the propeller type wind power generator is elastically twisted and deformed. The mounting bracket is attached via a flap's hinge so that the blade that can change the pitch angle in the direction can freely move the blade section in the vertical direction, and the blade tip of the blade is It is characterized in that an additional mass is attached to the leading edge or trailing edge near the wing tip, including the wing tip.

The invention described in claim 2 is a means for imparting an alignment function to the invention described in claim 1 as shown in FIG. 2, and is provided at the front or rear edge near the blade tip of the blade. The windmill is installed The invention according to claim 3 is characterized in that an additional mass body is attached to the trailing edge of the blade tip as the control member of the invention described in claim 1. It is characterized by

The invention described in claim 4 and subsequent claims is an invention necessary for putting the basic principle of the invention described in claims 1 to 3 into practical use. According to the invention described in claim 4, as shown in Fig. 3, the S-shaped plate panel A and the substantially linear plate spring B are fixedly mounted on the blade and the boss portion, respectively, and they are mounted as one. It is characterized in that it is connected with the hinge of the bracket so that the blade does not fall down when there is no wind, and that the blade does not flow downwind during startup.

According to the fifth aspect of the present invention, as shown in Fig. 4, the blade and the boss are connected by a coil-shaped panel coaxial with the hinge, and the blade does not fall down when there is no wind and the blade is started at the time of startup. It is characterized in that it does not flow downwind.

In the invention according to claim 6, as shown in Fig. 5, a stopper is provided on the blade or the boss portion by a top projection or a leaf spring C, and the stopper and the blade are provided. The special feature is that the blade is not completely swept downwind by the interference of the boss part 7 and the rotational force is maintained. '

According to the invention described in claim 7, a plate spring D is attached to the boss portion as shown in Fig. 6, and the movement of the blade in the concave cross-sectional direction is restrained by interference between the plate spring D and the plate. It is characterized by providing weather vane stability to the rotor. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an explanatory diagram of one embodiment of one blade in the wind turbine generator of the present invention. (A) is a perspective view. (B) is FIG. 3 is an explanatory view of a cross section of FIG 1 in a span direction. (C) is an explanatory sectional view in the span direction of another embodiment of Fig 1. (D) is a cross-sectional view taken along line A-A of Fig 1, (b) and line B-B of Fig 1 (c). (E) is a sectional view taken along the line C_C of Figl (c).

FIG. 2 is an explanatory diagram showing another embodiment of one blade in the wind turbine generator of the present invention. (Fig. 2-1) is a perspective view in which a control windmill is attached to the blade end via an additional mass body. (Fig. 2-2) is a cross-sectional view for explaining an embodiment in which additional mass bodies are attached to both sides of the blade. FIG. 3 is an explanatory view of a main part showing an embodiment of a mechanism for attaching a blade to the boss of the rotor of the wind turbine generator of the present invention. FIG. 4 is an enlarged front view of a main part of FIG. FIG. 5 is an enlarged side view of an essential part for explaining the mounting mechanism of the embodiment of the blade of the wind turbine generator of the present invention. FIG. 6 is an explanatory diagram of the windless state of FIG. FIG. 7 is a schematic diagram showing the operation of the wind turbine generator of the present invention. (Fig 7 — 1) indicates a windless state, (Fig 7 — 2) indicates a startup state,

(Fig 7-3) indicates the rated power generation state, (Fig 7-4) indicates the strong wind power generation state, and (Fig 7-5) indicates the rare power generator state under strong wind. Fig. 8 shows the relationship between the torsion angle of the blade at the blade tip of the wind turbine generator of the present invention and the stall, lift, and drag.

(Fig. 8-11) shows the relationship between lift and drag acting on a blade in a torsion angle state without stall. (Fig. 8-2) is a diagram showing the relationship between lift and drag acting on a blade in a torsion angle state that causes stall. Fig. 9 shows the torsion of the blade and the flange in the wind turbine generator of the present invention. Fig. 9 shows the relationship between the combined wind and the control wind turbine when the tip angle is large. (Fig 9-2) is the explanation from the plane and cross section of the plate. FIG. Fig. 10 shows the relationship between the combined wind and the control wind turbine when the flap angle is large. FIG. 11 is a diagram showing the relationship between the blade tip vortex and the rotation direction of the control wind turbine in the wind turbine generator of the present invention. (Fig 11 1 1 1) has a tip vortex. (Fig. 11-2) is an illustration of a single control windmill that draws a vortex in the wake. (Fig 11-3) describes another embodiment of a blade with weak tip vortex. FIG. 12 is a side view showing an outline of Embodiment 1 of the wind turbine generator of the present invention. Fig. 13 shows details of Example 1 of Fig. 12; (a) is a perspective view of the tip of the blade of Fig. 12; (b) is a view of the blade of Fig. 12; It is a principal part enlarged explanatory drawing which shows an attachment mechanism. FIG. 14 shows the outline of the embodiment '2 of the wind turbine generator of the present invention, where (a) is a side view and (b) is a perspective view of the blade tip of the blade. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the wind turbine generator of the present invention will be specifically described. Figure 2 shows the basic means.

Blade 1 is capable of changing pitch angle 0 in the span direction by elastic torsional deformation. For example, a thin blade having a single-arc-shaped structure is used. The blade 1 is freely rotatable with respect to the boss 7 only in the direction of the blade 1 flap (Figlb, Fig1c). Here, the flap shaft is not necessarily the rotating surface. As the wind speed increases, the blade 1 increases in the leeward direction; and the additional mass 2 is attached to the trailing edge of the wing tip of the pre- At the leading edge or trailing edge of the wing tip, a small control wind turbine 3 serving also as an additional mass body 2 that rotates substantially directly in the direction of travel of the blade 1 as a control member is provided. It is one of the main points of the present invention to impart the required elastic torsional deformation to the plate 1 during the rotation operation. Therefore, the material of the plate 1 is a tough, lightweight aluminum alloy having a wide elastic deformation range. Composite materials such as and FRP are desirable. The blade 1 in the present invention must have a property that it is much easier to twist than the blade 1 of a conventional wind turbine having a hollow or solid structure over its entire length, but the torsional rigidity (stiffness) is high. Has upper and lower limits.

The conditions of torsional rigidity that the blade 1 should satisfy in order to exert the function of the present invention include the inherent torsional rigidity of the blade 1, the total mass, the mass distribution, the generation of the blade 1 and the control windmill 3. It is difficult to determine the absolute value of the aerodynamic force, which varies depending on the number of revolutions, etc., but using the phenomenon that appears as a result of the interrelation of these factors, It can be described as follows.

When the blade tip pitch angle of the blade 1 in the mounted state is 0, that is, the angle between the rotation and the plane and the chord is positive, the upper limit of the torsional rigidity of the blade 1 is the blade 1 including the additional mass. Moment due to centrifugal force generated in the element and torsion moment generated by the blade 1 and the wind force generated by the control wind turbine 3 It is determined from the condition that the blade tip pitch angle 0 must be able to change to at least a negative value (pitch angle that gives the reverse rotation starting torque) in the following range. The lower limit of torsional stiffness is determined by the condition that the shape of the wing must be able to maintain its own shape against the gravity or the wind pressure below the starting wind speed in the cantilever support condition of the blade root. A typical example that satisfies the conditions is a thin, single-sheet arc wing with a thickness that is as small as possible without bending under its own weight.

Blade 1 to which the present invention can be applied is shown in Fig 1b. It is not limited to wings that have a thin cross section throughout the span direction. The condition for the elastic torsional deformation is that if the tip is twisted by about 30 degrees, which corresponds to the angle of attack at which stall will almost certainly occur with a normal airfoil, it is only within the elasticity range. That is, the cross section in the radial direction does not need to be a uniform thin plate structure, and as shown in Fig 1c, for example, the outside of the radius of approximately 1/2 is assumed to be an airfoil with a normal closed cross section, The inside of the remaining radius of approximately 1 Z 2 may be a thin plate structure, and the torsion may be handled by the thin plate structure.

Also, the cross section of the thin wing portion sharing twist is not necessarily an arc wing, but may be a cross section having excellent aerodynamic characteristics and easy to twist.

Now, blade 1 is freely rotatable in the flap direction, so that blade 1 above the rotating shaft does not fall down in the absence of wind and rotates when the wind blows. As shown in Fig. 3 and Fig. 4, the blade root of blade 1 is supported by leaf spring B or panel D to prevent it from being washed away. Here, if the leaf spring A is formed into an S-shape, the leaf spring A has a shape that is the most deformed, such that the S-shape is crushed even when the blade 1 is completely swept downwind. Therefore, it acts as a compressive force on the joint surface to the blade 1 and has a favorable effect on the strength design of the joint with the blade 1.

Also, if it is completely swept away by strong winds, the plate 1 loses its rotational force, the apparent rigidity due to centrifugal force also disappears, and it may be impossible to maintain its own shape under strong wind pressure. is there. Therefore, it is desirable to provide a device to limit the blade 1 from falling to the downstream side as shown in Fig5. For example, a stopper 8 or a panel C is attached. Furthermore, the wind turbine of the wind power generator of the present invention is In order to function as a downwind type without a weather vane, there must be a certain weather vane stabilizing effect, so a stopper such as a panel D as shown in Fig 6 must be used. It is desirable to provide.

Fig. 7 shows an outline of the operation status when the present invention is applied to a wind power generator.

When the wind blows, the plate 1 rotates around the flip axis against the restraint of the elastic members such as the panel panel by the wind pressure and flows downwind (Fig. 7-2). Since it is installed with a pitch angle of 0, it starts to rotate due to the torque component of its own aerodynamic force before it is completely swept away by the wind. When rotation starts, the flap angle returns to the windward side due to centrifugal force, and stable rotation is performed (Fig. 7-3). When the control wind turbine 3 is provided as a blade rotation control member, the control wind turbine 3 provides resistance to blade rotation.However, by setting the pitch angle の of the control wind turbine 3 deep, the rotor play is performed. The aerodynamic performance of the entire aircraft can be prevented from being significantly impaired. When the wind blows in a direction opposite to the wind direction in the 'operating state' as shown in Fig. 5, the blade 1 hits the stopper 8 and does not change its inclination. Therefore, the air resistance to blade 1 acts as a rotation moment about the windmill support shaft 11, so that blade 1 shows stable weather vane.

When the wind speed increases, the rotor speed increases, but as the speed increases, the plate-like plate 1 flattens at a pitch angle of 0 around the blade axis due to centrifugal force acting on each part. (Fig. 8-1). This effect is often known as the tennis 'racquet effect', where the wing tip is twisted in the direction of raising the head (leading edge) due to the moment, which makes it easy to twist. 1 makes the pitch angle 0 of the wing tip shallower. Also, if an additional mass is provided at the trailing edge of the wing tip, the wing tip (additional mass body) always tries to stay on the rotating surface due to centrifugal force. The torsional moment, which forcibly lowers the trailing edge of the wing tip toward the rotating surface, can be adjusted by the size of the additional mass. When the pitch angle 0 becomes shallower, the angle of attack α increases, and the wind pressure acting on the plate 1, that is, the force in the direction perpendicular to the rotating surface increases, acting to increase the flap angle, and confronting the wind Reduce the rotating area. A decrease in the rotating area leads to a decrease in the energy absorbed from the wind, which contributes to a decrease in the number of rotations, and consequently, the rotor does not increase the rotation speed and the change in the flap angle changes the wind speed. This will correspond to the increase. ,

As shown in Fig 8 _ 2, when blade 1 is twisted more than a certain degree, the blade tip of blade 1 with large deformation reaches pitch angle 近い close to zero or negative pitch angle 、, and the angle of attack α becomes too large and stall occurs at the tip of the wing. Since this stall slows down the rotation rate of the plate 1, the increase in the number of revolutions is suppressed and the flap angle] 3 is further increased (Fig 7-4).

If the additional mass is attached to the trailing edge of the blade wing and the torsional stiffness of the blade is set appropriately, the lap angle will automatically increase even if the wind speed further increases. Explain that it is possible to increase the wind pressure to escape the wind pressure and consequently to increase the rotation speed little.

At a certain wind speed, it is assumed that the flank angle is equal to or greater than a certain value, that is, the additional mass at the tip of the wing is balanced on the leeward side of the plane of rotation (Fig. 9-1). When the wind speed increases in this state, the aerodynamic force acting on the blade increases, so the rotation speed temporarily changes. However, due to the corresponding increase in centrifugal force, a torsional moment occurs in which the additional mass at the blade tip approaches the rotating surface. And the angle of attack at the tip of the wing will be further increased (Fig 9-2). As described later, when the flapping angle is large, the wind is obliquely received from the front of the blade root side (Fig. 10), so increasing the twist angle shifts the stall attack angle to the blade root side. Means this. In other words, the stall region of the blade further increases, and the lift component that gives the rotational torque decreases. Therefore, once the increased rotation speed decreases, the rotation speed increases, that is, the increase in the centrifugal force is suppressed in a stable and balanced state. On the other hand, the aerodynamic force consisting of the lift component and the anti-power component, which tries to increase the flap angle against the centrifugal force, increases as a whole due to the increase in the anti-power component. The flapping angle [3] determined by the ratio increases, and the blade 1 balances in such a way that the blade 1 flows downwind.

Thus, in principle, the position of the additional mass body at the trailing edge of the wing tip. Although the combination of the size and the torsional rigidity of the blade alone can suppress the increase in the number of revolutions, it is a real problem. These combinations may not be given freely. In that case, a wind turbine for controlling the wing tip can be provided to share the function of increasing the flap angle with the increase in wind speed.

The function of the control wind turbine is described below.

If the rigidity of the blade 1 is reduced and the additional mass 3 is attached to the blade tip, the torsion angle increases in accordance with the increase in the rotation speed due to the increase in wind speed, and the stall area increases. As the stall area increases, the rotational resistance of the plate increases; the rotational speed drops to a value close to the original value, and the centrifugal force does not change much. On the other hand, the wind pressure received in the direction of the rotation axis increases due to wind speed increase and stall. Therefore, the angle of inclination of the blade downstream, which is determined by the balance between the centrifugal force and the wind pressure in the direction of the rotating shaft, that is, the flapping angle] 3 increases. When the wind speed increases, the rotation speed does not change much and balances when the flapping angle] 3 increases. In some cases, flap control can be sufficiently performed. Too much twisting could cause blade 1 to bend by losing stiffness to movement in the plane of rotation. In such a case, it would exhibit dynamically unstable movement. Therefore, when the torsion angle or flap angle exceeds a certain value, it is desirable that the rotation speed can be controlled by a method other than the torsional deformation of the blade 1. The control wind turbine 3 performs this function. When the flapping angle increases, the control wind turbine 3 performs the function of increasing the flapping angle β only by aerodynamic characteristics.

FIG. 10 shows the relationship between the direction of the synthetic wind and the control wind turbine when the flap angle is large.

When the flapping angle [3] increases, blade 1 receives wind from obliquely forward on the blade root side with respect to the blade surface like a swept wing, and is placed at the tip of the blade. The control windmill 3 also receives the wind diagonally (Fig. 10a). The control wind turbine 3 that receives oblique wind generates not only drag against the relative wind but also lift (Fig 10b left side) in the direction perpendicular to the relative wind, like a disk wing formed on the rotating surface. Therefore, the resultant force becomes considerable, and both of them act as a resistance force (fig 10b right side) against the rotation of the blade 1.

In this case, Ω is the rotational angular velocity, and r is the radius of the plate. As a result, even if the wind speed increases, the rotation speed of the plate 1 does not increase and the centrifugal force does not increase. On the other hand, the force that increases the flap angle i3 of the plate 1 depends on the combined force of the lift and drag generated in the plate 1. You. Since the control wind turbine 3 does not generate a large force in the flap direction of the blade 1, the force for increasing the flap angle β does not decrease, and as a result, the blade 1 overcomes the centrifugal force. Therefore, the flapping angle J3 is further increased (Fig. 7-5).

Even if the windmill is located at the leading edge, it performs the same function. The rotation deceleration effect of the control wind turbine 3 increases with the flap angle, but as long as it is rotating, the rotation surface can be reduced even if the flap angle β increases. The feature is that it does not decline due to the effect of lift generation, and is effective until the flapping angle j3 force approaches S90 degrees. In other words, the wind turbine blade will continue to rotate and increase its flap angle until just before the umbrella is completely folded. At high wind speeds, it is easier to maintain the blade shape by continuing rotation, so blade 1 moves near the flapping angle force S 90 degrees and the sting shown in Fig 4 Stopped by eight.

As described above, the pitch angle Θ can be changed in the span direction by the elastic torsional deformation, and by using the blade 1 with the additional mass at the trailing edge of the wing tip, The additional moment by the additional mass body 3 provided at the trailing edge of the wing tip using the torsional moment, and the leading or trailing edge has a rotating surface generally facing the travel direction of the blade 1. By using or using the aerodynamic characteristics of the control wind turbine 3 mounted as described above as a control member, the flap angle / 3 is increased according to the wind speed over a large angle range, and the rotation speed is increased. Rotor that can suppress rising and maintain stable rotation ■ A blade can be realized. The rotation direction of the control wind turbine 3 is arbitrary, but the rotation in the direction to spread and diffuse the tip vortex reduces induction resistance due to the tip vortex and reduces noise. It is more desirable (Fig 11). The smaller the size of the control wind turbine 3, the better the overall efficiency of the wind turbine.

As described above, by using the plate 1 that can change the pitch angle 0 in the span direction by elastic torsional deformation, the torsional moment to the self due to the rotational inertia generated by the self and the leading or trailing edge By using the aerodynamic characteristics of the control wind turbine 3 mounted on the edge so as to have a rotating surface that roughly faces the direction of travel of the blade 1, it is possible to respond to the wind speed over a large angle range. By increasing the flap angle, it is possible to realize a rotor blade that can suppress a rise in the number of rotations and continue stable rotation.

The direction of rotation of the control wind turbine 3 is arbitrary, but rotation in the direction of spreading the tip vortex is desirable for reducing induced resistance and noise mitigation due to the tip vortex (Fig 11). The smaller the size of the control wind turbine 3, the higher the overall efficiency of the wind turbine.

By the way, in order to reduce the weight and cost, it is desirable that the blade 1 is a thin wing with a simple sectional shape of a single piece. For example, the arc wing is easily flap-hinged to the boss 7. Moreover, since it does not have a closed cross section, it has the characteristic of being easily twisted, which is convenient for application of the present invention. In addition, because the performance is not affected by the number of Reynolds, it is useful as a countermeasure for performance degradation when the number of Reynolds is small, which is an essential problem of conventional small wind turbines. It also has the advantage of

Example 1

Fig. 12 shows an example in which the blade mechanism of the wind power generator of the present invention is applied to a wind turbine of a wind power generator.

Blade 1 is an arc-shaped blade of blade 1 and a bar-shaped additional mass 2 is attached to the trailing edge of the blade tip. The rotation axis of the flap shaft of the wind turbine blade 1 is set so that only the flap angle j3 (the leeward angle of the blade) can rotate freely and the starting torque can be generated. It is mounted with a pitch angle 0 of about 20 degrees.

Plate panels A and B are attached to plate 1 and boss 7 via coupling hinge 5 to allow the flap movement of plate 1 and to prevent excessive movement on both the positive and negative sides. Have been. Note that a stopper is attached to the plate 1 so that the plate 1 hits the boss 7 when the plate 1 flows over a certain angle. In the embodiment, the upper limit is a flapping angle of] 380 degrees.

In the first embodiment, the blade 1 at the highest point is set to a flapping angle of about 30 degrees in a normal installation mode and no wind, and when the rotor surface becomes horizontal, the blade 1 The shape and strength of the panel are adjusted so that the flapping angle] 3 can be maintained at 0 degrees. In addition, the blade 1 is mounted so that one side of the rotor is on the leeward side during operation to obtain weather vane stability without the tail.

In the windless installation state, the plate 1 is within the range of the flapping angle of 30 ° to 0 ° due to the above-mentioned spring (FIG. 11).

'' For the wind from the convex side of blade 1, that is, the wind from the leeward side of the windmill, blade 1 attempts to reduce the flap angle, but its movement is restrained by the spring. Therefore, it shows the same weather vane stability as a normal down-wind propeller type wind turbine.

With respect to the wind from the concave side of blade 1, blade 1 had a flap angle of about 30 degrees, but the flap angle increased to about 45 degrees temporarily due to wind pressure. And each plate 1 has a pitch angle Θ Since it is installed in the center, it generates aerodynamic torque and starts to rotate (Fig. 7-2). When rotation starts, the flap angle e begins to decrease due to centrifugal force, and continues to rotate in a balanced state.

(Fig 7-3).

If this state is taken as the design point, the same performance as the conventional wind turbine can be achieved. '

As described above, the wind turbine continues to rotate while increasing the flapping angle / 3 without increasing the number of rotations significantly, as the wind speed increases. When the stall of the blade 1 starts, not only does the torsional moment acting on the additional mass on the wing tip increase with the wind speed, but also the angle of attack further decreases due to the moment. The circulation effect that the area is increased occurs, and the tendency that the flap angle increases as the wind speed increases but the rotation speed does not increase continues. As the wind speed further increases, blade 1 will keep rotating while hitting the stopper with the upper limit of flapper angle / 3. If the upper limit of the flap angle] 3 is set to 80 degrees, the frontal area of the rotor will be about 1/36 when the flap angle is zero, and the received dynamic pressure will also be 1/36. This means that if the rated wind speed is 10 m / s, the wind pressure is the same as that received during the rated operation even under a strong wind of 60 mZ s, and the strength is usually designed with an appropriate safety factor. In view of this, it is possible to design so that it can be operated without stopping rotation at practically any wind speed.

Example 2

Fig 14 shows another embodiment of the present invention.

The difference from the first embodiment is that a control windmill is attached to the trailing edge of the blade tip so as to make the control of the flap angle easier. As already described in detail for the operation of the control wind turbine, the wind speed does not depend strongly on the combination of the torsional stiffness of the blade and the additional mass, but is independent of itself when the flap angle is large. It has the advantage that it has the function of increasing the flap angle without increasing the number of revolutions, thereby facilitating the design of the blade system. The invention's effect

The wind power generator of the present invention can realize a method that does not cause over-rotation against a strong wind without providing a blade pitch angle control device, which is essential for a conventional wind turbine.

In addition, the concept of the present invention simplifies the structure of the blade, thus enabling significant cost reductions compared to conventional wind turbines, and significantly improving portability and ease of assembly. Can be expected. '

In addition, since a thin plate structure is acceptable for the blade, it is easy to ensure the quality, and the bending load is greatly reduced as compared with the conventional blade, and the stress acting on the blade is also reduced. Therefore, the present invention has a great advantage that it is superior to the conventional type in securing the fatigue strength, and has a great advantage in securing the fatigue strength. Since there is no concept of stopping a boat, that is, a blade, it has the feature that power generation near rated power can be continued even in strong winds.

In addition, thin blades such as arc blades do not have a drastic reduction in performance at low Reynolds numbers, which was inevitable for wind turbine blades with streamlined blade cross sections. It is possible to significantly improve the performance of wind turbines with a diameter of 10 m or less. Open the way. Industrial applicability

The wind turbine generator of the present invention provides clean wind energy by using clean renewable energy, even if the energy cost is low. It is an efficient wind turbine, improving many disadvantages of conventional wind turbines.

Claims

"The scope of the claims

'1

In the propeller type wind power generator, a blade capable of changing the pitch angle in the span direction by elastic torsional deformation is attached to the rotor post so that the blade section can freely rotate in the vertical direction. A wind power generator, characterized in that an additional mass is attached to the trailing edge near the wing tip including the wing tip. '

i'2

2. The wind power generator according to claim 1, wherein a small control wind turbine having a rotating surface substantially facing the traveling direction of the blade is attached to the blade tip of the blade.

;

An S-shaped leaf spring and a substantially linear leaf spring are fixed and attached to the blade and boss, respectively, and they are connected with a single hinge so that the blade does not fall down when there is no wind, and the blade does not fall when starting up. 3. The wind power generator according to claim 1, wherein the wind power generator is prevented from flowing downwindward.

! L4

The blade and the boss are connected by a coil-shaped panel coaxial with the flap hinge so that the blade does not fall down when there is no wind and the blade does not flow downwind during startup. Claims

Wind turbine generator according to 1 and 2.

Five

Provide a stopper in the form of a top projection or a leaf spring on the blade or boss so that it does not flow completely downwind due to interference between the stopper and the blade or boss. Claims 1 and 2 wherein the rotational force is maintained by A wind power generator as described.

; 6

Claims 1 and 2 characterized in that a leaf spring is attached to the pos part, and the movement of the blade in the concave cross-sectional direction is restrained by the interference between the leaf panel and the plate, thereby giving the rotor a stable weather vane. 2. The wind power generator according to 2.