CN113883021A

CN113883021A - Shaft structure, wind generating set shafting and wind generating set

Info

Publication number: CN113883021A
Application number: CN202111275634.4A
Authority: CN
Inventors: 马加伟; 方涛; 李会勋
Original assignee: Xinjiang Goldwind Science and Technology Co Ltd
Current assignee: Xinjiang Goldwind Science and Technology Co Ltd
Priority date: 2021-10-29
Filing date: 2021-10-29
Publication date: 2022-01-04
Also published as: WO2023071041A1

Abstract

The invention provides a shaft structure, a wind generating set shaft system and a wind generating set, wherein the whole shaft structure is of a cylindrical structure and comprises a bearing matching section, a shaft shoulder section and a stress buffering section which are sequentially connected, the bearing matching section is used for mounting a bearing, the outer surface of the stress buffering section is a curved surface which is concave towards the inner side, and the minimum outer diameter of the stress buffering section is smaller than the outer diameter of the bearing matching section and larger than the inner diameter of the bearing matching section. Adopt as above structure, through set up stress buffer section at shaft shoulder section rear side position, the stress that acts on shaft shoulder section corner originally just can be cushioned by stress buffer section, and the dispersion is to other positions of keeping away from the shaft shoulder section, can prevent effectively that the phenomenon of stress concentration from appearing in the shaft shoulder section.

Description

Shaft structure, wind generating set shafting and wind generating set

Technical Field

The invention relates to the technical field of wind power generation, in particular to a shaft structure, a wind generating set shaft system and a wind generating set.

Background

With the vigorous development of wind power generation, the power generation power of a wind generating set is gradually increased, the load borne by the wind generating set is also gradually increased, and a bearing structure of the wind generating set needs to be capable of bearing larger load so as to meet the power generation requirement of the wind generating set.

The bearing structure includes a bearing and a bearing-carrying structure, both of which need to have sufficient load-bearing capacity. When the bearing structure is applied, due to the structural complexity, the problem that stress is concentrated usually exists at the shaft shoulder, and the shaft shoulder is not enough to bear load at a corresponding position, so that the bearing structure is extremely easy to damage or has unqualified quality and the like.

In the prior art, the bearing structure of the partial bearing is transited by designing the shaft shoulder into a large arc shape or an oval shape and the like, and although the implementation mode can reduce the problem of stress concentration at the shaft shoulder, the shaft shoulder cannot be directly matched with the bearing, and only a transition ring is additionally arranged to connect the shaft shoulder and the end face of the bearing, so that the cost and the assembly time of the bearing structure are greatly increased; the stress concentration of a part of bearing structure is relieved by adding the groove at the shaft shoulder, but the stress concentration can be reduced only in a small range due to the limited size of the groove which can be processed, the problem of integral stress concentration at the shaft shoulder cannot be solved, and the groove can also be called as a fatigue hot spot of the integral bearing structure.

Therefore, how to provide a bearing structure of a wind turbine generator system capable of solving the problem of stress concentration at a shaft shoulder is a technical problem to be solved urgently by those skilled in the art.

Disclosure of Invention

The invention aims to provide a bearing structure of a wind generating set, which can solve the problem of stress concentration at a shaft shoulder.

In order to solve the technical problem, the invention provides a shaft structure, wherein the whole shaft structure is a cylindrical structure and comprises a bearing matching section, a shaft shoulder section and a stress buffering section which are sequentially connected, the bearing matching section is used for mounting a bearing, the outer surface of the stress buffering section is a curved surface which is concave towards the inner side, and the minimum outer diameter of the stress buffering section is smaller than the outer diameter of the bearing matching section and larger than the inner diameter of the bearing matching section.

Adopt as above structure, through set up stress buffer section at shaft shoulder section rear side position, the stress that acts on shaft shoulder section corner originally just can be cushioned by stress buffer section, and the dispersion is to other positions of keeping away from the shaft shoulder section, can prevent effectively that the phenomenon of stress concentration from appearing in the shaft shoulder section.

Optionally, the curvature of the front end of the stress buffering section to the minimum outer diameter position thereof is greater than the curvature of the minimum outer diameter position to the rear end of the stress buffering section.

Optionally, the difference between the minimum outer diameter of the stress buffering section and the inner diameter of the bearing fitting section is not less than 20 mm.

Optionally, the shaft structure further includes a second transition section connected to the stress buffering section, where the second transition section is a bell-mouth shaped structure, and the diameter of the second transition section smoothly increases from one end connected to the stress buffering section to the other end.

Optionally, the shaft structure further comprises a connecting section connected with the second transition section; and/or the shaft structure further comprises a first transition section connected with the bearing matching section.

Optionally, the outer diameter of the connecting section is larger than the outer diameter of the bearing mating section.

Optionally, the shoulder section has an outer diameter greater than an inner diameter of the bearing.

Optionally, a corner of the shoulder section facing the bearing fitting section is provided with a chamfer.

Optionally, the chamfer is a circular arc chamfer with a diameter of between 8-12 mm.

The invention also provides a wind generating set shafting, which comprises a plurality of bearings, a first shaft structure and a second shaft structure, wherein the second shaft structure is the shaft structure; the first shaft structure and the second shaft structure are rotatably connected by at least one of the bearings.

The invention also provides a wind generating set, which comprises a hub and a fan base, and further comprises a wind generating set shaft system arranged between the hub and the fan base, wherein the wind generating set shaft system is the wind generating set shaft system described above.

Drawings

FIG. 1 is a cross-sectional view of a shaft structure provided by an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a shafting of a wind turbine generator system according to an embodiment of the present invention;

FIG. 3 is a schematic stress flow diagram of a shaft structure at a shoulder section in accordance with an embodiment of the present invention;

FIG. 4 is a schematic stress flow diagram of a prior art shaft configuration at the shoulder section;

FIG. 5 is an enlarged schematic view of the shoulder section and stress buffering section of FIG. 1.

The reference numerals in fig. 1-5 are illustrated as follows:

the structure comprises a first transition section 1, a bearing matching section 2, a shaft shoulder section 3, a chamfer 31, a stress buffering section 4, a second transition section 5, a connecting section 6, a bearing 7, a first shaft structure 8, a shaft shoulder section 01 and a corner 02.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.

The embodiment of the invention provides a shaft structure, which is particularly used for mounting a bearing 7 of a wind generating set, and please refer to fig. 1, the shaft structure is integrally of a cylindrical structure, particularly a cylindrical structure, and a first transition section 1, a bearing matching section 2 matched with the bearing 7, a shaft shoulder section 3, a stress buffering section 4, a second transition section 5 and a connecting section 6 are sequentially arranged from the front end to the rear end.

The bearing matching section 2 is used for mounting the bearing 7, the length of the bearing matching section can be determined according to the axial length of the bearing 7 in practical application, and specifically can be slightly greater than the length of the bearing 7 so as to mount the bearing 7 better; the outer diameter of the bearing can be determined according to the inner diameter of the bearing 7 in practical application, and can be slightly smaller than or equal to the inner diameter of the bearing 7. As shown in fig. 1, M in fig. 1 is the outer diameter of the bearing fitting section 2, and M is the inner diameter of the bearing fitting section 2.

The shaft shoulder section 3 is used for axially limiting the bearing 7, and the outer diameter of the shaft shoulder section is larger than the inner diameter of the bearing 7. The axial length and the radial width of the shaft shoulder section 3 can be selected according to actual needs, the shaft shoulder section can be a simple protruding structure which can independently play a limiting role, and can also be fixed and integrated with other structures, for example, other fixed supporting parts are integrated to play roles of fixing and supporting other structures, so that the whole layout of the wind generating set is more convenient.

It should be noted that the outer surface of the stress buffering section 4 is a curved surface recessed inward, and the minimum outer diameter of the stress buffering section 4 is smaller than the outer diameter of the bearing fitting section 2 and larger than the inner diameter of the bearing fitting section 2.

Adopt as above structure, through set up stress buffer section 4 in 3 rear side positions of shaft shoulder section, the concentrated stress that acts on 3 corners of shaft shoulder section originally just can be cushioned by stress buffer section 4, disperses to other positions of keeping away from shaft shoulder section 3, can prevent effectively that the phenomenon of stress concentration from appearing in shaft shoulder section 3.

Referring to fig. 4, in the prior art, stress flows to the shoulder section 01 of the shaft structure for mounting the bearing of the wind turbine generator set as shown by an arrow in fig. 4, because the structure at the rear end of the shoulder section 01 extends and gradually expands towards the radial outside, the distribution trend of the stress in the shoulder section 01 is towards the radial outside, at this time, the stress flow of the shaft structure is gradually expanded from the front to the rear, and the stress flow is distributed to the corner 02 of the shoulder section 01, that is, when the position is marked by a circle in fig. 4, the shape of the corner 02 is suddenly changed, so that the stress concentration problem is generated at the position.

In this embodiment, the rear end of the shaft shoulder section 3 is connected with the stress buffering section 4, and the stress buffering section 4 adopts the above size, because the stress buffering section 4 is sunken towards the radial inner side first, and then extends towards the radial outer side, the conduction of stress towards the radial outer side is delayed, the stress flow is distributed more evenly as a whole, and the minimum external diameter of the stress buffering section 4 is less than the external diameter of the bearing matching section 2 and is greater than the internal diameter of the bearing matching section 2, so that the stress distribution is close to the inner side of the shaft structure as much as possible and deviates from the outer surface of the bearing matching section 2. At this time, referring to fig. 3, at the corner of the shoulder section marked by a circle in fig. 3, due to the offset of the stress flow position (having a certain offset relative to fig. 4), the stress is less affected by the shape jump, so that the stress concentration at the position can be reduced or prevented.

Continuing with fig. 5, more specifically, the location of the minimum outer diameter of the stress buffering section 4 is identified as O, of course, the position may be a point position or a section, and as mentioned above, the whole outer surface of the stress buffering section 4 is a curved surface, the outer diameter of the stress buffering section 4 has a certain curvature, and in this embodiment, the curvature from the front end of the stress buffering section 4 to the minimum outer diameter position is greater than the curvature from the minimum outer diameter position to the rear end of the stress buffering section 4, in fig. 5, where the front end of the stress buffering section 4 is denoted by P and the rear end by Q, it can be seen that the curve from P to O is steeper, and the curved surface of O to Q is more gentle, and PO is more precipitous and easily realizes pulling down the stress flow as soon as possible, reduces the stress flow and distributes to the position of shaft shoulder section 3, and OQ is more gentle, is favorable to the evenly distributed of stress to and link up gently with the second transition section 5 of back.

It should be noted that, referring to fig. 1, the front end is the left end in fig. 1, the rear end is the right end in fig. 1, the axial direction is the left-right direction in fig. 1, and the radial direction is the up-down direction in fig. 1.

In the embodiment of the present invention, the first transition section 1 of the shaft structure is disposed at the foremost end, and may be used to bear other structures at the front end of the bearing 7, as shown in fig. 2, the first transition section 1 may be mounted with the bearing 7 at the front end. The specific length of the first transition section 1 may be determined according to the specific needs in practical applications, and the shape thereof may be a planar structure or a curved structure, which is not limited in the present invention.

Stress buffer segment 4 is as before for the stress of buffering shaft shoulder section 3 corner disperses to other positions of keeping away from shaft shoulder section 3, prevents that shaft shoulder section 3 from appearing stress concentration phenomenon. In fig. 1, N is the minimum outer diameter of the outer surface of the stress buffering section 4, in this embodiment, the minimum outer diameter of the stress buffering section 4 is smaller than the outer diameter of the bearing matching section 2 and larger than the inner diameter of the bearing matching section 2, that is, M is smaller than N and smaller than M, and when the minimum outer diameter of the stress buffering section 4 is within the range, the effect of buffering stress is better; the longer the axial length of the stress buffering section 4 is, the better the effect of buffering the stress is.

Further, in the embodiment, the difference between the minimum outer diameter of the stress buffering section 4 and the inner diameter of the bearing matching section 2 is not less than 20 mm, and when the minimum outer diameter of the stress buffering section 4 is in the above range, the effect of buffering the stress is better.

Second changeover portion 5 sets up in the rear end of stress buffer section 4, it is horn mouth shape structure, second changeover portion 5 is from the one end of connecting stress buffer section 4 to the one end diameter smooth increase of connecting link 6, its from the front end to the smooth increase of rear end diameter promptly, the gyration curve of horn mouth is shape such as circular arc or elliptical arc, so set up, it can with the cooperation of stress buffer section 4, the stress of better buffering shaft shoulder section 3, prevent that the stress concentration phenomenon from appearing in shaft shoulder section 3.

The connecting section 6 is used for connecting the shaft structure with other components, for example, the shaft structure can be fixed on a base of a wind generating set, the axial length of the connecting end 6 can be determined according to the length of a fastener used for connection in practical application, the invention is not limited to this, the outer diameter of the connecting end is larger than that of the bearing matching section 2, the difference is more, and the inner diameter can be equal to or close to that of the bearing 7.

In addition, a chamfer 31 may be provided at the front end corner of the shoulder section 3 to further reduce possible stress concentrations. Because this embodiment is provided with stress buffer section 4, has improved the stress concentration phenomenon, and chamfer 31 here can accomplish very little, for example between 8-12mm, can select the circular arc chamfer of diameter 10mm in this embodiment to can carry out spacing cooperation with bearing 7 better.

The present invention further provides a wind turbine generator system, please refer to fig. 2, which includes a plurality of bearings 7, a first shaft structure 8 and a second shaft structure, where the second shaft structure is the shaft structure described above, and since the shaft structure has the technical effects as above, the wind turbine generator system including the shaft structure should also have the same technical effects, and thus, the details are not repeated herein.

The first shaft structure 8 and the second shaft structure are rotatably connected through a plurality of bearings 7, and the first shaft structure and the second shaft structure can rotate relatively through the plurality of bearings 7 to drive the generator rotor and the generator stator to rotate mutually to generate electricity. The shaft structure of the present invention is not limited to being an inner shaft or an outer shaft, and is not limited to being a rotating shaft or a fixed shaft. As shown in fig. 2, the bearing 7 in the present embodiment includes a front bearing provided at the front end of the first transition section 1 and a rear bearing provided at the bearing fitting section 2.

The invention also discloses a wind generating set, which comprises a hub and a wind generator base, and also comprises a wind generating set shaft system arranged between the hub and the wind generator base, wherein the wind generating set shaft system is the wind generating set shaft system.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that it is obvious to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements should also be considered as the protection scope of the present invention.

Claims

1. A shaft structure, characterized in that: the whole tubular structure that is of shaft structure, it is including bearing cooperation section (2), shaft shoulder section (3) and the stress buffering section (4) that meet in proper order, bearing cooperation section (2) are used for installing bearing (7), the surface of stress buffering section (4) is the curved surface of inboard sunken, the minimum external diameter of stress buffering section (4) is less than the external diameter of bearing cooperation section (2), and is greater than the internal diameter of bearing cooperation section (2).

2. The shaft structure according to claim 1, wherein: the curvature from the front end of the stress buffering section (4) to the minimum outer diameter position of the stress buffering section is larger than the curvature from the minimum outer diameter position to the rear end of the stress buffering section (4).

3. The shaft structure according to claim 1, wherein: the difference between the minimum outer diameter of the stress buffering section (4) and the inner diameter of the bearing matching section (2) is not less than 20 mm.

4. A shaft structure according to any one of claims 1 to 3, characterized in that: the shaft structure further comprises a second transition section (5) connected with the stress buffering section (4), wherein the second transition section (5) is of a horn-mouth-shaped structure, and the diameter of the second transition section smoothly increases from one end connected with the stress buffering section (4) to the other end.

5. The shaft structure according to claim 4, wherein: the shaft structure further comprises a connecting section (6) connected with the second transition section (5);

and/or the shaft structure further comprises a first transition section (1) connected with the bearing matching section (2).

6. The shaft structure according to claim 5, wherein: the outer diameter of the connecting section (6) is larger than that of the bearing matching section (2).

7. A shaft structure according to any one of claims 1 to 3, characterized in that: the outer diameter of the shaft shoulder section (3) is larger than the inner diameter of the bearing (7).

8. A shaft structure according to any one of claims 1 to 3, characterized in that: and a chamfer (31) is arranged at the corner of the shaft shoulder section (3) facing the bearing matching section (2).

9. The shaft structure according to claim 8, wherein: the chamfer (31) is a circular arc chamfer with the diameter of 8-12 mm.

10. A wind generating set shafting which characterized in that: comprising a number of bearings (7), a first shaft structure (8) and a second shaft structure, the second shaft structure being a shaft structure according to any of claims 1-9;

the first shaft structure (8) and the second shaft structure are rotationally connected by means of at least one bearing (7).

11. The utility model provides a wind generating set, includes wheel hub and fan base which characterized in that: the wind turbine further comprises a wind turbine generator system shafting arranged between the hub and the fan base, wherein the wind turbine generator system shafting is the wind turbine generator system shafting of claim 10.