WO2020013019A1

WO2020013019A1 - Rotor blade support structure for electrical generator

Info

Publication number: WO2020013019A1
Application number: PCT/JP2019/026211
Authority: WO
Inventors: 広平小野; 近藤　博光
Original assignee: Ntn株式会社
Priority date: 2018-07-09
Filing date: 2019-07-02
Publication date: 2020-01-16
Also published as: JP7042176B2; JP2020007978A

Abstract

This rotor blade support structure for an electrical generator rotatably supports a vertical axis type rotor blade (1) and transmits the rotation of the rotor blade (1) to an electrical generator (2) located below the rotor blade (1). A circular cylindrical bearing case (4) is rotatably mounted on the outer periphery of the case (5) of the electrical generator (2) through ring-shaped bearings (9, 9). The bearing case (4) is coaxially joined to the rotor blade (1) and is connected to the electrical generator shaft (2a) of the electrical generator (2). The bearing case (4) is provided with a circular cylindrical case body (4a) and an end plate (4b) which is provided at one axial end of the case body (4a) and to which the rotor blade (1) is joined.

Description

Rotor blade support structure for generator

Related application

This application claims the priority of Japanese Patent Application No. 2018-130131 filed on Jul. 9, 2018, the entire contents of which are incorporated herein by reference.

The present invention relates to a rotor supporting structure for a generator, and to a technique applied to a wind power generator and a hydroelectric generator.

Since a wind power generator is generally installed in a natural environment and operates basically using irregular wind energy as a power, a relatively large load acts on components of the wind power generator (Patent Document 1, 2).

FIG. 5 is a sectional view showing the arrangement and configuration of a generator and the like used in a conventional vertical axis wind turbine. In the wind power generator, in addition to the power generation torque generated by the lift or drag of the blade 50a of the rotary wing 50, a bending load generated by the wind pressing the wind receiving surface of the blade 50a is generated. The bending load and the generated torque are received by the generator shaft 51a and the bearing 52 of the generator 51, and the diameter of the shaft is increased to cope with this.
FIG. 6 shows a structure in which the intermediate shaft 53 is set to reduce the bending load acting on the generator shaft 51a of the generator 51, and the load is not directly received by the generator shaft 51a of the generator 51. In this case, the bending load can be absorbed by the intermediate shaft 53, but the distance between the shafts increases, and the entire device becomes larger.

The power generation torque is relatively stable because the moment of inertia of the rotor impedes rapid changes, while the bending load that the wind pushes against the wind receiving surface is extremely shocking. In the calculation, it is necessary to estimate many static effects, and as a result, the shaft diameter must be increased.

On the other hand, some large wind turbines have an assist mechanism for improving startability (Patent Document 3), but it is difficult to provide an assist mechanism for a small wind turbine from the viewpoint of cost.

JP 2016-89736 A JP 2006-322445 A JP-A-8-322298

因子 Factors attributable to the startability of a wind turbine without an assist mechanism include friction loss, inertia loss, and viscous loss. In this case, friction loss is dominant because the problem before starting movement is a problem. Although friction loss occurs from an oil seal, a bearing, and the like, it has been technically shown that in both cases, the friction loss largely depends on the shaft diameter. Therefore, suppressing the bending load unnecessary for power generation and reducing the shaft diameter leads to an improvement in startability.

An object of the present invention is to provide a rotor supporting structure for a generator that can improve the startability of a power generator and improve power generation efficiency.

The rotor support structure for a generator according to the present invention rotatably supports a vertical shaft type rotor, and transmits the rotation of the rotor to a generator or a gearbox located below the rotor. Rotor support structure of
A cylindrical bearing case is rotatably mounted on the outer periphery of the case of the generator or the gearbox via a ring-shaped bearing, and the bearing case is coaxially coupled to the rotating blade and the generator Or the input shaft of the gearbox.

According to this configuration, a cylindrical bearing case is rotatably installed on the outer periphery of the case of the generator or the gearbox via a ring-shaped bearing, and this bearing case is connected to the rotor blades and the power generation of the generator. Connected to the input shaft of the gearbox or gearbox. For this reason, a load other than the rotational force generated when the rotor blades receive wind power or hydraulic power, that is, a bending load acting on the generator shaft or the input shaft of the gearbox, can be received by the bearing case and the bearing.
In this case, it becomes possible to increase the section modulus of the structure as compared with receiving a bending load on the shaft, and the bearing only needs to have a small load capacity. Further, since the generator shaft or the input shaft of the gearbox is connected to the bearing case and is not directly connected to the rotor, the bending load hardly acts, and therefore, only the torsional load, which is the power generation torque, is applied. This can be taken into consideration, and the shaft diameter can be reduced. As a result, the friction loss of the generator or the gearbox can be reduced, the startability of the power generator can be improved, and the power generation efficiency can be improved.

The bearing case may be connected to a generator shaft of the generator or an input shaft of the gearbox via a torque transmission coupling. Even when the generator shaft or the input shaft of the gearbox and the rotor are provided coaxially, a deviation in coaxiality may occur due to an installation error or aging deterioration. In this case, due to the alignment of the torque transmitting coupling, the coaxiality is adjusted to a desired value by absorbing a deviation of the coaxiality due to an installation error between the generator shaft or the input shaft of the gearbox and the rotating blade or deterioration over time. Can be secured. Therefore, the friction loss of the generator or the gearbox can be further reduced, and the startability of the power generator can be improved.

The bearing case includes a cylindrical case main body, and an end plate provided at one axial end of the case main body and coupled with the rotating blade, and the end plate is fitted to the case main body with an intaglio. You may. According to this configuration, since the bearing case and the rotor are coaxial, and the rotor is coupled to the end plate of the bearing case, the end plate and the rotor are coaxial.
Further, since a cylindrical case body is rotatably installed via bearings on the outer periphery of the case of the generator or the speed-up gear, the input shaft of the generator shaft or the speed-up gear rotatably supported by the case, Desired coaxiality is secured with respect to the axis of the case body. Furthermore, since the end plate is fitted to the case body, the coaxiality between the generator shaft or the input shaft of the gearbox and the rotor can be easily secured to a desired value, thereby reducing costs. Can be planned. Therefore, the friction loss of the generator or the gearbox can be further reduced, and the startability of the power generator can be improved.

環状 An annular seal member may be provided at a fitting portion between the case body and the end plate. In this case, the sealing property in the bearing case is sufficiently ensured, and the life of the generator or the gearbox can be extended.

ベアリング The bearing case may be provided with one or both of a concave portion and a convex portion for increasing the surface area. In this case, since the surface area of the bearing case increases, heat radiation from the bearing case is promoted. As the recess, for example, a slit may be provided at a position other than the bearing fitting portion of the bearing case.

放熱 A fan for heat dissipation may be provided in the generator or the speed increaser. In this case, for example, by rotating the fan in synchronization with the rotation of the generator or the gearbox, heat radiation of the generator or the gearbox can be promoted.

どの Any combination of at least two configurations disclosed in the claims and / or the specification and / or the drawings is included in the present invention. In particular, any combination of two or more of the following claims is included in the present invention.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and figures are for illustration and description only and should not be used to define the scope of the invention. The scope of the invention is defined by the appended claims. In the attached drawings, the same part numbers in a plurality of drawings indicate the same parts.
It is a sectional view of a rotor supporting structure of a generator concerning a 1st embodiment of this invention. It is the expanded sectional view which expanded a part of the rotating blade support structure. It is the end view of the modification form which changed the rotary wing support structure partially. It is an end elevation of another modification which changed the same rotor support structure partially. It is sectional drawing of the rotor support structure of the generator which concerns on 2nd Embodiment of this invention. It is sectional drawing showing the rotating blade support structure of the generator of the prior art example. It is sectional drawing showing the rotor blade support structure of the generator of other conventional examples.

[First Embodiment]
A rotor support structure for a generator according to a first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows an example in which the rotor support structure of the generator is applied to a vertical axis wind turbine type wind power generator. The vertical axis wind turbine type wind turbine includes a rotor 1, a generator 2, and a rotor support 3.

<Rotary wing 1>
The rotor 1 has a plurality of blades 1a extending in the vertical direction and a support 1b. The rotary wing 1 is of a lift type that rotates by the lift received by the blade 1a. A plurality of blades 1a are attached to a rotor support 3 described later via a support 1b extending in the horizontal direction. The number of the blades 1a is, for example, two, and is provided at a position having a phase difference of 180 ° with respect to the rotation axis L. The number of blades 1a may be three or more.

<Generator 2>
The generator 2 is located below the rotor 1. The generator 2 is provided in a bearing case 4 of the rotor support 3. The generator 2 generates electric power by rotating the generator shaft 2 a by the rotation of the rotor 1. The generator 2 is, for example, a three-phase AC generator of a permanent magnet synchronous type, an induction type or the like, or a single-phase AC generator, and includes a case 5, a stator 2b, a rotor 2c, a bearing 6 in the generator, and a generator shaft 2a. Have.

The case 5 has a cylindrical shape extending in the up-down direction, and the lower end in the axial direction of the case 5 is supported and attached to the support plate 7. A generator shaft 2a is rotatably supported on the inner peripheral surface of the case 5 via generator

inner bearings

6,6. The bearing 6 in the generator is a rolling bearing such as a deep groove ball bearing, an angular ball bearing, and a tapered roller bearing. The stator 2b is fixed to the inner peripheral surface of the case 5, and the rotor 2c is fixed to the outer peripheral surface of the generator shaft 2a. The rotor 2c faces the stator 2b with a predetermined gap therebetween. When the rotor 2c rotates together with the generator shaft 2a, the generator 2 generates power. The power generated by the generator 2 is supplied to an external power system via a wiring (not shown).

<Rotary wing support part 3>
As shown in FIGS. 1 and 2, the rotor support section 3 rotatably supports the rotor 1 and transmits the rotation of the rotor 1 to the generator 2. The rotor support 3 includes a support member 7, a bearing case 4, a bearing 9, a torque transmission coupling 10, and an annular seal member 11. The support member 7 in this example has a support substrate 7a fixed to the upper end member 12a of the tower support 12 by bolts 13 and a fixing member 7b fixed to the upper surface of the support substrate 7a. However, the support member 7 may be an integral member formed from the same material. The tower support 12 is formed of, for example, a steel tower, and a plate-like upper end member 12a extending in the horizontal direction is provided at the top of the steel tower. Cylindrical bearing cases 4 are rotatably installed at a plurality of upper and lower locations on the outer periphery of a case 5 of the generator 2 via ring-shaped

bearings

9, 9. The ring-shaped bearing 9 is a so-called thin-type rolling bearing in which a bearing height obtained by dividing a value obtained by subtracting the inner ring inner diameter from the outer ring inner diameter from the outer ring by 2 is formed thinner than a general bearing. , Rolling bearings such as deep groove ball bearings, angular contact ball bearings, and tapered roller bearings.

The bearing case 4 is coaxially coupled to the rotor 1 and connected to the generator shaft 2a of the generator 2 via a torque transmitting coupling 10 having an aligning property. The bearing case 4 includes a cylindrical case main body 4a and an end plate 4b fastened to the case main body 4a by bolts 14. The support 1b is fixed to the upper end surface of the end plate 4b via a bracket 15. An annular seal portion 16 is provided on the lower surface of the end plate 4b, and the end plate 4b is fitted to the upper end portion (one axial end portion) of the case body 4a in the axial direction by the seal portion 16. An annular seal member 11 is provided at a fitting portion between the case main body 4a and the end plate 4b.

例えば As the annular seal member 11, for example, packing or the like is applied. At the center of the lower surface of the end plate 4b, a shaft portion 17 protruding in the axial direction is provided, and the shaft portion 17 is provided coaxially with the generator shaft 2a. The generator shaft 2 a is connected to the shaft portion 17 via the torque transmission coupling 10. Although the shaft portion 17 is provided coaxially with the generator shaft 2a, a deviation in coaxiality may occur due to an installation error or aging deterioration. The torque transmission coupling 10 absorbs a deviation in coaxiality due to an attachment error between the shaft portion 17 and the generator shaft 2a or deterioration over time. Note that the generator shaft 2a can be directly connected to the shaft portion 17 of the end plate 4b without the torque transmission coupling 10 interposed therebetween.

<Effects>
According to the rotating blade support structure of the generator described above, the cylindrical bearing case 4 is rotatably installed on the outer periphery of the case 5 of the generator 2 via the ring-shaped

bearings

9, 9. 4 is connected to the rotor 1 and connected to the generator shaft 2a of the generator 2. For this reason, the bearing case 4 and the

bearings

9 and 9 can receive a load other than the rotational force generated when the rotor blade 1 receives the wind, that is, a bending load acting on the generator shaft 2a.
In this case, it becomes possible to increase the section modulus of the structure as compared with receiving a bending load on the shaft, and the bearing 9 need only have a small load capacity. Further, since the generator shaft 2a is connected to the bearing case 4 and is not directly connected to the rotary wing 1, no bending load is applied. Therefore, only the torsional load, which is the generation torque, needs to be considered. The diameter can be reduced. As a result, the friction loss of the generator 2 can be reduced, the startability of the wind turbine generator can be improved, and the power generation efficiency can be improved.

The bearing case 4 is connected to the generator shaft 2a via a torque transmission coupling 10. Because of the alignment of the torque transmitting coupling, the coaxiality between the generator shaft 2a and the rotary blade 1 can be maintained at a desired value. Therefore, the friction loss of the generator 2 can be further reduced, and the startability of the wind power generator can be improved.
Since the bearing case 4 and the rotor 1 are coaxial, and the rotor 1 is coupled to the end plate 4b of the bearing case 4, the end plate 4b and the rotor 1 are coaxial.
In addition, since the cylindrical case body 4a is rotatably installed on the outer periphery of the case 5 of the generator 2 via the bearing 9, the generator shaft 2a rotatably supported by the case 5 has the axis center of the case body 4a. , A desired coaxiality is secured. Further, since the end plate 4b is fitted to the case main body 4a with the intaglio, the coaxiality between the generator shaft 2a and the rotary wing 1 can be easily secured to a desired value, whereby the cost can be reduced. . Therefore, the friction loss of the generator 2 can be further reduced, and the startability of the wind power generator can be improved.
Since the annular seal member 11 is provided at the fitting portion between the case main body 4a and the end plate 4b, the sealing property inside the bearing case 4 is sufficiently ensured, and the life of the generator 2 can be extended.

発電 As shown in FIG. 1, the generator 2 may be provided with a fan 18 for heat radiation. In this example, the rotating shaft 18a of the fan 18 is connected to the lower end of the generator shaft 2a. In this case, by rotating the fan 18 in synchronization with the rotation of the generator 2, wind can be sent from a ventilation hole (not shown) formed in the tower support 12, and heat radiation of the generator 2 can be promoted.

<Other embodiments>
In the following description, the same reference numerals are given to portions corresponding to the items described earlier in each embodiment, and overlapping description will be omitted. In the case where only a part of the configuration is described, the other parts of the configuration are the same as the previously described embodiment unless otherwise specified. The same operation and effect can be obtained from the same configuration. Not only the combination of the parts specifically described in the respective embodiments, but also the embodiments can be partially combined with each other as long as the combination is not particularly hindered.

<Heat dissipation structure>
3a and 3b show an example in which the shape of the bearing case 4 is changed in the first embodiment, and a part (for example, line III-III in FIG. 2) of the case body 4a is cut in a horizontal direction and viewed. FIG. As shown in FIG. 3A, a plurality of recesses 19 that are recessed radially inward from the outer peripheral surface may be formed on the outer peripheral surface of the case main body 4 a of the bearing case 4. The recesses 19 are recesses for increasing the surface area, and are formed, for example, at regular intervals in the circumferential direction and include slits extending in the axial direction.

As shown in FIG. 3B, the concave portions 19 and the convex portions 20 may be alternately formed in the circumferential direction on the outer peripheral surface of the case main body 4a. Each projection 20 is formed of a ridge extending in the axial direction. Although not shown in the following, a plurality of convex portions may be formed on the outer peripheral surface of the case main body 4a so as to project a predetermined distance radially outward from the outer peripheral surface. Either one or both of the concave portion and the convex portion may be provided at a portion other than the bearing fitting portion on the inner peripheral surface of the case main body 4a. One or both of the concave portion and the convex portion may be provided in a part of the end plate 4b. One or both of the concave portion and the convex portion may be formed in an annular shape on the peripheral surface of the case main body 4a.
According to these configurations, since the surface area of the bearing case 4 increases, heat radiation from the bearing case 4 is promoted.

<Example of application to gearbox>
As shown in FIG. 4, a speed increaser 21 for increasing the rotation of the rotor 1 and transmitting the rotation to the generator 2 is provided like the rotor support structure of the generator according to the second embodiment of the present invention. A cylindrical bearing case 4 may be rotatably mounted on the outer periphery of a case 21 a of the speed change device 21 via ring-shaped

bearings

9, 9. The bearing case 4 is coaxially coupled to the rotor 1 and is connected to the input shaft 21b of the gearbox 21.

For example, the speed increaser 21 increases the rotation of the input shaft 21b and transmits the rotation to a low-speed shaft (not shown). And a secondary speed increasing device (not shown) for transmission. The input shaft 21b is connected to the shaft 17 of the end plate 4b in the bearing case 4, and the output shaft 21c is connected to the generator 2. Although not shown, the angle of the rotating shaft may be changed by 90 ° by connecting the output shaft 21c of the gearbox 21 to the generator shaft via a bevel gear or the like.

<Drag-type vertical axis wind turbine>
In each embodiment, an example is shown in which the vertical axis wind turbine is a lift type. However, in some cases, the configuration of the present invention may be applied to a drag type vertical axis wind turbine.

<Example of application to a hydroelectric generator>
In each embodiment, the rotor support structure is applied to a vertical axis windmill type wind power generator, but the rotor support structure may be applied to a hydraulic power generator.

As described above, the preferred embodiment has been described with reference to the drawings. However, those skilled in the art will readily see various changes and modifications within the obvious scope by referring to the present specification. Accordingly, such changes and modifications are to be construed as being within the scope of the invention as defined by the appended claims.

DESCRIPTION OF SYMBOLS 1 ... Rotor blade 2 ... Generator 2a ... Generator shaft 5 ... Case 4 ... Bearing case 4a ... Case main body 4b ... End plate 9 ... Bearing 10 ... Torque transmission coupling 11 ... Annular sealing member 18 ... Fan 19 ... Depression Reference numeral 20: convex portion 21: gearbox 21b: input shaft

Claims

A rotor support structure for a generator that rotatably supports a vertical axis type rotor and transmits the rotation of the rotor to a generator or a gearbox located below the rotor,
A cylindrical bearing case is rotatably installed on the outer periphery of the case of the generator or the speed increaser via a ring-shaped bearing. A rotor support structure for a generator connected to a generator shaft of the machine or an input shaft of the gearbox.
The generator rotor blade supporting structure according to claim 1, wherein the bearing case is connected to a generator shaft of the generator or an input shaft of the gearbox via a coupling for transmitting torque. Rotor wing support structure.
3. The rotating blade support structure for a generator according to claim 1, wherein the bearing case is provided at a cylindrical case main body and an end provided at one axial end of the case main body and coupled with the rotor blade. 4. A rotating blade support structure for a generator, comprising: a plate;
The rotating blade support structure for a generator according to claim 3, wherein an annular seal member is provided at a fitting portion between the case body and the end plate.
The power generator according to any one of claims 1 to 4, wherein the bearing case includes one or both of a concave portion and a convex portion for increasing a surface area. Rotor wing support structure of the machine.
The rotor blade support structure for a generator according to any one of claims 1 to 5, wherein the generator or the speed increaser is provided with a fan for heat radiation.