JP2001020850A - Wind power generating device having damping function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wind power generating device having a damping device to damp a tower in correspondence to the frequency band of vibration generated by rotation of blades or the like. SOLUTION: This device comprises a generator 14 having a drive source being the rotation force of blades 12 generated by a wind force; and a tower 16 to support the blades. The tower is provided with a damping device 18 to perform damping by variably synchronizing vibration, generated by rotation of the blades and wind, with its frequency. The damping device is provided with an elastically deformable engaging means 30 to engage a movable mass body 20 and the tower with each other and a function to vary the spring constant of the engaging means. The engaging means forms a movable joint member located between an elastically deformable rod-form member 32, erected on the tower, and the mass body. Further, this device comprises a moving means for a joint member; a detecting means for number of revolutions of blade; and control means 26 to control a moving amount of the moving means according to the result of the detecting means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wind power generator for generating power using wind power, and more particularly to a wind power generator having a vibration damping function for damping a tower that supports blades rotated by wind at a predetermined height. Related to the device.

[0002]

2. Description of the Related Art A wind power generator that generates power by utilizing the energy of natural wind has a blade that is rotated by wind power attached to the top of a tower, and a generator is operated by using the rotating force of the blade as a drive source. ing.

[0003] Such wind power generators are shifting to large wind power generators that can cope with changing wind intensities. For example, in this large-scale wind power generator, there is a type in which the blade length (rotation diameter) of a blade is 40 m to 50 m or more and a variable pitch type is used. In this case, the tower has a height to allow rotation of the blade. Is 30 m to 40 m or more. The vibration frequency at the optimum rotation speed of the blade of the large-sized wind turbine is 0.75H.
z is about 1.5 Hz. On the other hand, height 30m-40m
The primary natural vibration frequency of a class-grade tower is about 1.0 Hz, so the vibration frequency generated by the blade may match the natural vibration frequency of the tower, preventing both resonances occurring in this case. For this purpose, the tower is provided with a passive vibration damping device adapted to its natural vibration frequency.

[0004]

The range of wind speeds at which power can be generated by such a conventional wind power generator is limited to a narrow range in accordance with the number of revolutions of the generator. The range of wind speeds at which power can be generated has been widened by methods such as intervening transmissions, and it has become possible to generate power at low wind speeds of several m / s to strong winds of 20 m / s.

However, the range of wind speeds at which power can be generated includes tens of m / sec, which is a resonance wind speed that causes divergent vibration due to Karman vortex excitation of the tower, and the tower may resonate.

[0006] In addition, since the range of wind speeds at which power can be generated is widened, the frequency of blades and the frequency band of forced vibration generated by the rotation are also widened. In particular, in the case of a steel tower having a low vibration damping property, there is a problem that the durability of the tower may not be secured against the resonance due to the resonance wind speed or the forced vibration due to the rotation of the blade. there were.

Accordingly, the present invention has been made in view of such a conventional problem, and the durability of the tower is ensured by damping the tower in accordance with the frequency band of the vibration generated by the rotation of the blade or the like. It is an object of the present invention to provide a wind power generation device provided with a vibration damping device that can perform the operation.

[0008]

According to a first aspect of the present invention, there is provided a wind power generator provided with a vibration damping device, comprising: a blade rotating by wind power; And a tower that supports the blade at a predetermined height, wherein the vibration frequency to be damped in the tower in the frequency band of the vibration generated by the rotation of the blade or the wind And a vibration damping device that variably tunes the vibration damper is provided.

That is, the vibration damping device provided in the tower can change the frequency of vibration damping within the frequency band of vibration generated in the tower by the rotation or wind of the blade. Since it can be tuned variably to various frequencies of generated vibration, even if the rotation frequency of the blade fluctuates according to the wind speed that changes from time to time, even if the vibration frequency generated in the tower changes, it can be tuned to the vibration frequency Tower vibration can be effectively suppressed.

According to a second aspect of the present invention, there is provided a wind power generator provided with a vibration damping device, wherein the vibration damping device comprises a mass, a support for movably supporting the mass, and a tower. And an elastically deformable engaging means for engaging the mass body, wherein the engaging means is formed so that a spring constant relating to the elastic deformation can be changed.

That is, since the mass body is movably supported by the tower, the mass body can move with the vibration of the tower, and the mass body and the tower are elastically deformed with a considerable spring constant. Since the tower is engaged by the engagement means, the tower is provided with a passive-type vibration damping device that damps by moving the mass body under the elasticity of the engagement means. By changing the spring constant of the combining means, the frequency to be damped (tuning frequency) can be variably adjusted.

Therefore, even if the frequency of the forced vibration due to the rotation of the blade changes due to a change in the wind speed, the spring constant of the engaging means is changed, and the vibration damping device is variably tuned to that frequency to thereby oscillate the tower. Can be easily suppressed.

Further, in the wind power generator provided with the vibration damping device according to the third aspect of the present invention, the engaging means may include an elastically deformable rod-shaped member which is fixed to the lower end and erected on the tower. And a joint member interposed between the rod-shaped member and the mass body, wherein the joint member is formed so as to be movable along the rod-shaped member.

That is, since the bar-shaped member having the lower end fixed to the tower is engaged with the mass body via the movable joint member, the rod-shaped member and the mass body come into contact with each other by the joint member. When the mass body moves, a stress due to the mass body acts on the rod-shaped member at the contact portion with the joint member. At this time, the elastically deformable rod-shaped member is flexed and deformed by receiving a stress from the mass with the fixing portion to the tower as a fulcrum, and the mass moves within a range where the rod-shaped member can be flexed and deformed.

When the frequency at which the mass body moves and the vibration frequency of the tower are synchronized, the mass body moves with a delay with respect to the vibration phase of the tower, thereby canceling the mutual vibrations and thereby causing the vibration of the tower. Thus, a passive type vibration damping device capable of suppressing vibration is formed. At this time, the tuning frequency of the vibration damping device is set by the distance between the fixed end of the rod-shaped member and the contact portion of the joint member.

Further, since the joint member is formed so as to be movable along the rod-shaped member, the vibration damping device can be variably tuned to the vibration frequency of the tower, thereby easily suppressing the vibration of the tower. Can be.

Further, a wind power generator provided with a vibration damping device according to a fourth aspect of the present invention is a moving means for moving the joint member along the rod-shaped member, and a detecting means for detecting the number of rotations of the blade. And control means for controlling the amount of movement of the moving means according to the detection result of the detecting means.

That is, since the rotation speed of the blade is detected,
The frequency of the forced vibration of the tower generated by the rotation of the blade is provided because the rotation speed of the blade fluctuating due to the wind can be accurately grasped and the moving means for moving the joint member according to the detected rotation speed is provided. Can easily and accurately tune the damping device,
This makes it possible to reliably and efficiently suppress the vibration of the tower.

[0019]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 6 show an embodiment of a wind power generator according to the present invention. FIG. 1 is an external view showing the entirety of a wind power generator provided with a vibration damper. FIG. FIG. 3 is a plan view showing the structure of the vibration damping device provided in the wind power generator, FIG. 4 is a side view showing the structure of the vibration damping device, and FIG. FIG. 6 is a detailed plan view of the means for engaging with the mass body, and FIG. 6 is a block diagram showing a control method of the vibration damping device in the present embodiment.

As shown in FIG. 1, the basic structure of a wind power generator 10 according to the present invention is as shown in FIG.
And a generator 14 driven by the rotational force of the blade 12
And a tower 16 for supporting the blade 12 at a predetermined height. The tower 16 is provided with a vibration damping device 18 for damping the vibration of the tower 16.

The blades 12 are provided at equal intervals in the circumferential direction with respect to the center of rotation, and three blades 12 are provided.
Is provided with a variable pitch mechanism that is rotatable at its mounting portion. The rotation of the blade 12 is controlled by the generator 14
The power is input to a power generation rotor via a transmission incorporated therein, and power is generated by rotation of the rotor. The blades 12 are integrally attached to a generator 14 and the integrated blades 12 and generator 14 are
At a predetermined height. The tower 16 is constructed in a S-shaped structure using a steel plate into a tapered cylindrical shape with a slight taper, and is erected from a foundation B cast on the ground G.

In this embodiment, the generator 14 has a power generation capacity of 500 kW and a power generation wind speed of 2.5 m / s to 22.0 m / s.
And the blade length of the variable pitch type blade 12 is set to 46 m. The rotation speed of the blade 12 is 45 rpm (0.75 rpm) at a wind speed of 3 m / s to 4 m / s.
Hz) and 90 rpm (1.5 Hz) when the wind speed is 10 m or more, and the rotor rotation speed at this time is 3 m / s to 4
The speed is 14 rpm (0.25 Hz) at m / s, and 29 rpm (0.5 Hz) at a wind speed of 10 m or more. Further, the generator 14
The size of the tower 16 that supports is 34.35 m in height,
The outer diameter is 2.90 m at the bottom and 2.20 m at the top, and its natural frequency is 1.05 Hz.

As shown in FIG. 2, the vibration damping device 18 has a mechanical portion 28 which constitutes a mechanical structural portion of the vibration damping device 18,
A rotation speed detecting means provided on the rotation axis of the blade, and a control means for setting a mechanism unit to a frequency to be tuned in accordance with a detection result of the detection means; Is mounted on a stage 36 provided on the upper end side.

As shown in FIGS. 3 to 6, the mechanism section 28 is made of a rectangular parallelepiped mass body 20 and a laminated rubber for movably supporting the four corners of the mass body 20 on the stage 36 of the tower 16. It comprises a support body 22 and an engagement means 30 for engaging the stage 36 with the mass body 20.

The engaging means 30 is provided on a stage 36 and is made of a steel rod-shaped member 32 which is deformed by being pressed by stress within its allowable elastic deformation range, and a rod-shaped member penetrating through the rod-shaped member 32. The joint member 34 includes a joint member 34 movably provided along the line 32, a moving unit 38 for moving the joint member 34, and a driving unit 42 for driving the moving unit 38.
Is provided with a well-known position detecting means 46 for detecting a distance L between the joint member 34 and the stage 36.

The mass body 20 is provided with a through hole 20a vertically penetrating the center of the mass body 20. The through hole 20a has a planar shape along the longitudinal direction of the mass body 20, and one end thereof. Has a rectangular shape, the other end has a semicircular shape, and the diameter thereof is formed as a hole width.

A semicircular inner peripheral wall of the through hole 20a is provided with a steel pipe 20b having a circular shape and the same diameter, and a half of the outer peripheral surface thereof is fixedly provided. Are divided into two to form two spaces. Further, a slit 20c is formed in the center of the outer peripheral surface facing the inside of the through hole 20a of the steel pipe 20b along the vertical direction.
Is provided, and the two spaces communicate with each other.

In the steel pipe 20b, the rod-shaped member 3 of the engaging means 30 erected from the stage 36 of the tower 16 is provided.
2 is inserted and provided with a joint member 34 penetrated by the rod-shaped member 32 and formed to be vertically movable.

The joint member 34 has a substantially ring shape, and an inner peripheral portion thereof is provided with a bearing for sliding in contact with the outer periphery of the rod-shaped member 32. The outer peripheral surface of the joint member 34 is formed of the steel pipe 20b. Slide on the inner peripheral surface.

The joint member 34 is provided with a connecting portion 34a for connecting with the moving means 38 extending from a slit 20c provided in the steel pipe 20b.

In the outer space of the steel pipe 20b in the through hole 20a, an elevating shaft 38a having a screw forming a feed screw mechanism formed on the surface thereof is rotatable at the upper and lower ends of the mass body 20. In addition to being supported and provided, the elevating shaft 38a is extended upward, and a gear 38c is provided at the extended portion.

On the other hand, a motor 38 is provided above the mass body 20.
b is provided, and a gear 38d provided on the motor shaft is engaged with a gear 38c of the elevating shaft 38a. Further, the elevating shaft 38a has an elevating body 38 which forms a feed screw mechanism together with the elevating shaft 38a.
e is screwed.

The elevating body 38e is connected to the connecting portion 34a of the joint member 34 in the through hole 20a to form an integral body.

That is, when the motor 38b provided above the mass body 20 rotates, the moving means 38
The elevating shaft 38a connected via c and 38d rotates, and the elevating body 38 screwed to the elevating shaft 38a
e rises and falls along the inner peripheral surface of the through hole 20a. At this time, the joint member 34 integrated with the elevating body 38e
Is formed so as to move up and down while sliding on the inner peripheral surface of the steel pipe 20b along the rod-shaped member 32, and change the position where the rod-shaped member 32 comes into contact with the mass body 20 via the joint member 34 up and down. .

The distance L from the fixed portion of the rod-shaped member 32 to the contact position with the joint member 34 receiving the stress of the mass body 20 is changed by the moving means 38,
The spring constant of the rod-shaped member 32 can be changed to an arbitrary value.

FIG. 6 is a block diagram showing the control of the tuning frequency of the vibration damping device 18 in this embodiment.

The means 24 for detecting the number of revolutions and wind speed of the blade 12 comprises an encoder or the like provided on a rotating shaft between the blade 12 and the generator 14. The detection results are sequentially transmitted to the control means 26. ing.

The control means 26 includes the detection means 2
4, the frequency of the forced vibration by the blade 12 is calculated based on the detection result sent from the
In order to synchronize 8, the spring constant relating to the bending deformation of the rod-shaped member 32 is changed.

That is, the vibration damping device 18 in this embodiment
In this control, the number of rotations and the rotation speed of the blade 12 are detected by the detecting means 24, and the detection result and the detected wind speed are sequentially transmitted to the control means 26.

In addition to the detection means 24, the tower 1
A vibration detecting means 40 for detecting the vibration of the stage 36 representing the vibration of No. 6 is provided.

Further, the position data of the joint member 34 is transmitted from the position detecting means 46 of the joint member 34 to the control means 26.

The detection results sent from the detection means 24 and the vibration detection means 40 are input to the control means 26 through the interface 44, and based on the detection results, the rotation of the blade 12 and the The frequency of the forced vibration is calculated, and the spring constant of the bar-shaped member 32 is calculated to tune the vibration damping device 18 to the calculated frequency.

The rod-shaped member 32 is calculated based on the calculated spring constant.
The driving means 4 is controlled by the control means 26 so that the
2, a control signal is transmitted to the motor 3 of the moving means 38.
8b, the joint member 34 is moved up and down while comparing the position of the joint member 34 with the data transmitted from the position detecting means 46. Then, the mass body 2 engaged with the rod-shaped member 32 by the joint member 34
0 is tuned to the forced vibration frequency of the blade 12 and moved.

In the wind power generator 10 of the present embodiment having the above configuration, the vibration damper 18 provided in the tower 16
Is tuned to the vibration frequency generated in the tower 16 by the rotation of the blade 12 or the wind, so that the rotation frequency of the blade 12 fluctuates according to the wind speed that changes from time to time, and the vibration frequency generated in the tower 16 changes. The vibration of the tower 16 can be effectively suppressed by tuning the vibration damping device 18 to the vibration frequency.

Further, the mass body 20 can be freely moved.
, The mass body 20 can move with the vibration of the tower 16, and the mass body 20 and the tower 16 are engaged by the engagement means 30 that elastically deforms with a considerable spring constant. Therefore, the tower 16 is formed with a passive type vibration damping device 18 for damping by the movement of the mass body 20 under the elasticity of the engaging means 30. By changing the spring constant of 30, the tuning frequency can be variably adjusted.

That is, since the bar-shaped member 32 which is fixed to the tower 16 and constitutes the engaging means 30 is engaged with the mass body 20 via the movable joint member 34, the rod-shaped member 32 is provided. The member 32 contacts the mass body 20 by the joint member 34, and when the mass body 20 moves, the rod-shaped member 32
Is applied. At this time, the elastically deformable rod-shaped member 32 is fixed to the tower 16 as a fulcrum, and the mass 2
The flexure is deformed by receiving a stress from 0, and the mass body 20 moves within a range where the flexure is possible.

When the vibration frequency generated by the movement of the mass body 20 and the vibration frequency of the tower 16 are synchronized with each other, the mass body 20 moves with a delay with respect to the vibration phase of the tower 16, so that the two move mutually. The passive type vibration damping device 18 that can suppress the vibration of the tower 16 by canceling the vibration is formed.

The frequency to be tuned by the vibration damping device 18 is
The spring constant is set by the spring constant of the rod-shaped member 32, and the spring constant is adjusted by the distance L between the fixed end of the rod-shaped member 32 and the contact portion of the joint member 34. Further, since the joint member 34 is formed so as to be movable along the rod-shaped member 32, the vibration damping device 18 can be variably tuned to the vibration frequency of the tower 16.

That is, even if the frequency of the forced vibration caused by the rotation of the blade 12 changes due to a change in the wind speed, the spring constant is changed, and the vibration of the tower 16 is variably tuned to the frequency to reduce the vibration of the tower 16. It can be easily suppressed.

Further, since the rotation speed of the blade 12 is detected, the rotation speed of the blade 12 which fluctuates due to the wind can be accurately grasped, and the joint member 34 is moved by the moving means 38 according to the detected rotation speed. The tower 1 generated by the rotation of the blade 12
6 can be accurately and easily tuned to the frequency of the forced vibration, and the tower 16 can be effectively tuned.
Vibration can be suppressed.

In the present embodiment, the embodiment in which the steel rod-shaped member 32 is used for the elastically deformable engaging means 30 of the vibration damping device 18 has been described, but the member used for the engaging means 30 is not limited to this. The invention is not limited to this, and any material may be used as long as it has elasticity such as a leaf spring and can easily change the spring constant as in the above embodiment, and the material is not limited to steel.

Although the support 22 of the mass body 20 is made of laminated rubber, the support 22 is not limited to this.

[0053]

As described above, in the wind power generator provided with the vibration damping device according to the first aspect of the present invention, the vibration damping device provided on the tower is adjusted to the vibration frequency generated by the rotation of the blade. Even if the frequency of rotation of the blade fluctuates according to the wind speed that changes from time to time and the vibration frequency generated in the tower changes, the vibration control device is tuned to the vibration frequency to effectively tune the tower vibration. Can be suppressed.

In the wind power generator having the vibration damping device according to the second aspect of the present invention, the spring constant relating to the elastic deformation of the engaging means for engaging the mass body and the tower can be changed. Since it is formed, the tuning frequency can be variably adjusted by changing its spring constant.
Therefore, the vibration of the tower can be suppressed by easily tuning the vibration damping device to the forced vibration frequency of the blade.

Further, in the wind power generator having the vibration damping device according to claim 3 of the present invention, the elastically deformable rod-shaped member fixed to the tower is connected to the mass body via the movable joint member. The engagement allows the tuning frequency of the vibration damping device to be variably adjusted by moving the position of the joint member, thereby easily tuning the vibration damping device to the vibration frequency of the tower, and Can be suppressed.

Furthermore, since the wind turbine generator having the vibration damping device according to the fourth aspect of the present invention detects the rotation speed of the blade, it can accurately grasp the fluctuating rotation speed of the blade. The joint member is moved by the moving means in accordance with the detected number of rotations, and the vibration damping device can be accurately tuned to the forced frequency generated in the tower, so that the tower vibration can be reliably and effectively suppressed.

[Brief description of the drawings]

FIG. 1 is an external view showing an entire embodiment of a wind turbine generator provided with a vibration damping device of the present invention.

FIG. 2 is an explanatory diagram showing an installation state of a vibration damping device provided in a wind turbine generator according to an embodiment of the present invention.

FIG. 3 is a plan view illustrating a structure of a vibration damping device provided in the wind turbine generator according to the embodiment of the present invention.

FIG. 4 is a side sectional view showing a structure of a vibration damping device provided in a wind turbine generator according to an embodiment of the present invention.

FIG. 5 is a detailed plan view of engagement means between a tower and a mass body of the vibration damping device provided in the wind turbine generator according to the embodiment of the present invention.

FIG. 6 is a block diagram illustrating control of a damping frequency of a damping device provided in the wind turbine generator according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Wind power generator 12 Blade 14 Generator 16 Tower 18 Vibration suppression device 20 Mass body 20a Through hole 20b Steel pipe 20c Slit 22 Support body 24 Detecting means 26 Control means 28 Mechanism part 30 Engaging means 32 Rod member 34 Joint member 38 Moving means 38a lifting shaft 38b motor 38c, 38d gear 38e lifting body 40 vibration detecting means

Claims (4)

[Claims] 1. A wind turbine generator comprising: a blade that is rotated by wind power; a generator that uses a rotational force of the blade as a driving source; and a tower that supports the blade at a predetermined height. A wind power generator having a vibration damping function, wherein a vibration damping device is provided, which variably tunes to a vibration frequency to be damped in a frequency band of vibration generated by the rotation of the blade or wind. . 2. The vibration damping device according to claim 1, further comprising: a mass body; a support body that movably supports the mass body; and an elastically deformable engagement unit that engages the tower with the mass body. The wind power generator having a vibration damping function according to claim 1, wherein the engagement means is formed so as to be able to change a spring constant related to its elastic deformation. 3. An elastically deformable rod-shaped member, the lower end of which is fixed to the tower, and which is fixed to the tower, and a joint member interposed between the rod-shaped member and the mass body. The wind power generator having a vibration damping function according to claim 2, wherein the joint member is formed so as to be movable along the rod-shaped member. 4. A moving means for moving the joint member along the rod-like member, a detecting means for detecting the number of rotations of the blade, and controlling a moving amount of the moving means according to a detection result of the detecting means. The wind power generator having a vibration damping function according to claim 3, further comprising a control unit that performs the control.