CN113969876A - Wind generating set shafting and wind generating set - Google Patents
Wind generating set shafting and wind generating set Download PDFInfo
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- CN113969876A CN113969876A CN202111277281.1A CN202111277281A CN113969876A CN 113969876 A CN113969876 A CN 113969876A CN 202111277281 A CN202111277281 A CN 202111277281A CN 113969876 A CN113969876 A CN 113969876A
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- bearing
- contact angle
- generating set
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- wind generating
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D80/00—Details, components or accessories not provided for in groups F03D1/00 - F03D17/00
- F03D80/70—Bearing or lubricating arrangements
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Wind Motors (AREA)
Abstract
The invention provides a wind generating set shafting and a wind generating set, wherein the wind generating set shafting comprises a fixed shaft and a rotating shaft sleeved on the radial outer side of the fixed shaft, the fixed shaft is connected with a fixed part of the wind generating set, the rotating shaft is connected with a hub, the fixed shaft and the rotating shaft are connected through a first bearing and a second bearing which are distributed along the axial direction, the first bearing is close to the center of the hub, the second bearing is far away from the center of the hub, the first bearing and the second bearing are both conical roller bearings, and the contact angle of the second bearing is between 18 and 26 degrees. Adopt as above structure, the second bearing mainly bears the axial force of wheel hub to the fan base, and when the second bearing adopted above-mentioned scope, its bearing axial force that can be better improved the load bearing capacity of wind generating set shafting, and compares other contact angle angles, and the second bearing can reach the same effect under the condition that the volume is littleer, effectively reduces the material cost of second bearing, and then reduces the overall cost of wind generating set shafting.
Description
Technical Field
The invention relates to the technical field of wind power generation, in particular to a wind generating set shafting 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 of the wind generating set comprises an upwind bearing and a downwind bearing, so that the hub can rotate relative to the fan base to drive the generator to generate electricity. When the upwind bearing and the downwind bearing both adopt tapered roller bearings, the whole load bearing capacity of the bearing structure is larger. The industry is currently not optimizing the specific arrangement of tapered roller bearings.
Disclosure of Invention
The invention aims to provide a specific optimized arrangement mode of a tapered roller bearing.
In order to solve the technical problems, the invention provides a wind generating set shafting and a wind generating set, which comprise a dead axle and a rotating shaft sleeved on the radial outer side of the dead axle, wherein the dead axle is fixed on a fan base, the dead axle is connected with a fixed part of the wind generating set, the rotating shaft is connected with a hub, the dead axle and the rotating shaft are connected through a first bearing and a second bearing which are distributed along the axial direction, the first bearing is close to the hub, the second bearing is far away from the hub, the first bearing and the second bearing are both conical roller bearings, and the contact angle of the first bearing is between 14 and 25 degrees.
Adopt as above structure, the second bearing mainly bears the axial force of wheel hub to the fan base, and when the second bearing adopted above-mentioned scope, its bearing axial force that can be better improved the load bearing capacity of wind generating set shafting, and compares other contact angle angles, and the second bearing can reach the same effect under the condition that the volume is littleer, effectively reduces the material cost of second bearing, and then reduces the overall cost of wind generating set shafting.
Optionally, the contact angle of the first bearing 5 is between 22 and 25 degrees and the contact angle of the second bearing 6 is between 21 and 24 degrees.
Optionally, the first bearing 5 has a contact angle between 14 and 17 degrees and the second bearing 6 has a contact angle between 24 and 26 degrees.
Optionally, the first bearing 5 has a contact angle between 18 and 21 degrees and the second bearing 6 has a contact angle between 18 and 21 degrees.
Optionally, the first bearing 5 has a contact angle between 14 and 25 degrees.
Optionally, the first bearing 5 has a contact angle between 14 and 18 degrees.
Optionally, the first bearing 5 has a contact angle between 15 and 17 degrees.
Optionally, the first bearing 5 has a contact angle between 19 and 21 degrees.
Optionally, the contact angle of the first bearing 5 is between 23 and 25 degrees.
A wind generating set 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.
Drawings
FIG. 1 is a cross-sectional view of a shafting of a wind turbine generator system according to the present invention;
fig. 2 is an enlarged schematic view of the positions of the first and second bearings of fig. 1.
The reference numerals in fig. 1-2 are illustrated as follows:
the fan comprises a fixed shaft 1, a rotating shaft 2, a fan base 3, a hub 4, a first bearing 5, a second bearing 6, a rotating shaft 7 and a fixing structure 8.
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 wind generating set shafting, please refer to fig. 1 and fig. 2, and the shafting comprises a fixed shaft 1 and a rotating shaft 2 sleeved on the radial outer side of the fixed shaft 1, wherein the fixed shaft 1 is connected with a fixed part of the wind generating set, the rotating shaft 2 is connected with a hub 4, the fixed shaft 1 and the rotating shaft 2 are connected through a first bearing 5 and a second bearing 6 which are distributed along the axial direction, the first bearing 5 is close to the center of the hub 4, the second bearing 6 is far away from the center of the hub 4, and the first bearing 5 and the second bearing 6 are both tapered roller bearings. The fixing component of the wind generating set may be a main frame or a fan base 3, and the fan base 3 is taken as an example for description hereinafter, but the fixing component in the present invention is not limited to the fan base 3.
As shown in fig. 1 and 2, α in fig. 1 and 2 is a contact angle of the first bearing 5, and β is a contact angle of the second bearing 6. Second bearing 6 sets up in the radial outside of dead axle 1, is close to fan base 3's one end, and second bearing 6 is located to the radial inboard cover of one end that pivot 2 is close to fan base 3, and dead axle 1 and pivot 2 can rotate relatively through second bearing 6, drive the relative generator stator mutual rotation who is connected with dead axle 1 with the generator rotor that pivot 2 is connected to generate electricity.
The inventor carries out stress research on the shafting of the wind generating set, as shown in fig. 1, the second bearing 6 is in a downwind direction and bears most of the axial force of the hub 4 to the fan base 3, and the sources of the axial force include the thrust of wind to the blades and the hub 4, for example.
Therefore, the second bearing 6 mainly bears the axial force of the hub 4 to the fan base 3 and needs better axial bearing capacity, so that the larger the contact angle of the second bearing 6 is, the stronger the axial force bearing capacity is, the better load bearing capacity is obtained, and the integral load bearing capacity of the shafting of the wind generating set is enhanced. The second bearing 6 in this embodiment is a tapered roller bearing and has a contact angle of between 18 and 26 degrees, preferably between 22 and 26 degrees.
In addition, a first bearing 5 is arranged between the rotating shaft 2 and the fixed shaft 1, and the first bearing 5 is in an upwind direction and bears most of radial force of the hub 4 to the fan base 3, and sources of the radial force comprise the hub 4, gravity of blades and the like.
Therefore, the first bearing 5 mainly bears the radial force and needs good radial bearing capacity, so that the first bearing 5 can have stronger bearing capacity when the contact angle is smaller, and the integral load bearing capacity of the shafting of the wind generating set is enhanced. The first bearing 5 of this embodiment is a tapered roller bearing and has a contact angle of between 14 and 25 degrees, preferably between 14 and 18 degrees.
In combination with the aforementioned stress analysis of the first bearing 5 and the second bearing 6, the combination of the two is further studied, and the service life of the two is considered when verifying the bearing capacity.
Through comparative analysis of different combinations of the contact angles of the first bearing 5 and the second bearing 6 through the central load of the hub 4, if the contact angle of the second bearing 6 is set to be 18 degrees, the smaller the contact angle of the first bearing 5 is, the longer the service life of the first bearing is, but an inflection point appears when the contact angle of the second bearing 6 reaches 16 degrees; if the contact angle of the first bearing 5 is fixed to 18 degrees, the service life of the second bearing 6 is longer as the contact angle is smaller, but the service life of the first bearing 5 is an inflection point when the contact angle of the second bearing 6 reaches 23 degrees. It can be seen that when the contact angle of one bearing is determined, an inflection point appears as the contact angle of the other bearing increases to some extent.
The second bearing 6 mainly bears an axial force, a contact angle can be relatively large, but the smaller the contact angle, the higher the fault tolerance rate of the end cover compression amount of the fan base 3 by the wind generating set shafting is, namely the smaller the contact angle, the easier the assembly with the fan base 3 is, in addition, the smaller the bearing contact angle, the smaller the weight and the lower the cost are, and at the moment, the service life is considered, the contact angle of the second bearing 6 can be smaller, preferably, the contact angle of the second bearing 6 is 21-24 degrees, the contact angle of the first bearing 5 is 22-25 degrees, the service life of the wind generating set shafting is longer, and the cost of the shafting is lower.
The contact angle of the first bearing 5 may also be set to be smaller in view of the service life of the second bearing 6, for example, the combination is selected such that the contact angle of the first bearing 5 is between 14 and 17 degrees and the contact angle of the second bearing 6 is between 24 and 26 degrees.
In addition, the influence of the static safety factor and the internal stability of the shafting of the wind generating set can be considered.
By comparing the combinations of the contact angles of the first bearing 5 and the second bearing 6 with the extreme load at the center of the hub 4, the inflection point appears when the contact angle of the first bearing 5 is about 14 to 16 degrees when the contact angle of the second bearing 6 is selected to be 18 to 20 degrees. In addition, in order to ensure the internal stability of the shafting of the wind generating set, the loads borne by the first bearing 5 and the second bearing 6 should be uniformly distributed as much as possible, and the analysis on the internal stability of the shafting of the wind generating set can be obtained by combining different contact angles of the first bearing 5 and the second bearing 6, the difference value of the contact angles of the first bearing 5 and the second bearing 6 is not too large, and the contact angle of the first bearing 5 is not too large, so that the loads of the first bearing 5 and the second bearing are distributed relatively uniformly, and the internal stability of the shafting of the wind generating set is improved. Therefore, the contact angle of the second bearing 6 is selected to be between 18 and 21 degrees, the contact angle of the first bearing 5 is selected to be between 18 and 21 degrees, the static safety factor and the internal stability of the wind generating set shafting are high, and compared with the above combination, the wind generating set shafting is the second preferred scheme.
In addition, the influence of temperature sensitivity is also taken into account.
Through the combination of different contact angles of the first bearing 5 and the second bearing 6, the comparison analysis of temperature sensitivity can be carried out, on the premise that the center span, the inner diameter and the outer diameter of the first bearing 5 and the second bearing 6 are determined, the smaller the contact angles of the first bearing 5 and the second bearing 6 are, the larger the influence of the pretightening force of the first bearing and the second bearing on the temperature sensitivity is, therefore, the larger the contact angles of the first bearing 5 and the second bearing 6 are, the lower the temperature sensitivity of the whole shafting of the wind generating set is, therefore, the combination of the contact angle of the second bearing 6 being selected between 18 and 20 degrees and the contact angle of the first bearing 5 being selected between 14 and 16 degrees also has better temperature sensitivity.
On the basis of this, the preferred contact angle of the first bearing 5 differs according to the depth of the first bearing 5 extending into the hub 4 and the distance between the first bearing 5 and the second bearing 6 in practical applications. The closer the first bearing 5 is to the hub 4, the smaller the preferable contact angle is, and the contact angle of the first bearing 5 is preferably between 15 and 17 degrees, and the arrangement mode is first preferable, the whole volume of the first bearing 5 is smaller, and the bearing capacity is higher;
the closer the distance between the first bearing 5 and the second bearing 6, the greater the preferred contact angle of the first bearing 5, in which case the contact angle of the first bearing 5 is preferably between 19 and 21 degrees, this arrangement being second preferred;
and when the first bearing 5 is farther from the hub 4 and closer to the second bearing 6, the contact angle of the first bearing 5 is preferably between 23 and 25 degrees, which is the third preferred arrangement.
Still include fixed knot structure 8 in this embodiment, fixed knot structure 8 can cooperate with pivot 2, carries on spacingly in axial direction to first bearing 5.
Referring to fig. 1, the fixing structure 8 is disposed at an end of the fixed shaft 1 away from the fan base 3, and cooperates with the rotating shaft 2 to limit the first bearing 5 therebetween, so that the first bearing cannot be separated from the space between the fixed shaft 1 and the rotating shaft 2.
The invention also discloses a wind generating set, which comprises a hub 4 and a fan base 3, and also comprises a wind generating set shaft system arranged between the hub 4 and the fan base 3, 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 (10)
1. A wind generating set shafting which characterized in that: locate including dead axle (1) and cover dead axle (1) pivot (2) in the radial outside, dead axle (1) is connected with wind generating set's fixed part, pivot (2) are connected with wheel hub (4), dead axle (1) with pivot (2) are connected through first bearing (5) and second bearing (6) along axial distribution, first bearing (5) are close to the center of wheel hub (4), keep away from second bearing (6) the center of wheel hub (4), first bearing (5) with second bearing (6) are tapered roller bearing, the contact angle of second bearing (6) is between 18 to 26 degrees.
2. A wind power generation assembly shafting according to claim 1, wherein: the first bearing (5) has a contact angle between 22 and 25 degrees and the second bearing (6) has a contact angle between 21 and 24 degrees.
3. A wind power generation assembly shafting according to claim 1, wherein: the first bearing (5) has a contact angle between 14 and 17 degrees and the second bearing (6) has a contact angle between 24 and 26 degrees.
4. A wind power generation assembly shafting according to claim 1, wherein: the first bearing (5) has a contact angle between 18 and 21 degrees and the second bearing (6) has a contact angle between 18 and 21 degrees.
5. A wind power plant shafting according to any of claims 1 to 4, wherein: the contact angle of the first bearing (5) is between 14 and 25 degrees.
6. A wind power generation assembly shafting according to claim 5, wherein: the contact angle of the first bearing (5) is between 14 and 18 degrees.
7. A wind power generation assembly shafting according to claim 5, wherein: the contact angle of the first bearing (5) is between 15 and 17 degrees.
8. A wind power generation assembly shafting according to claim 5, wherein: the contact angle of the first bearing (5) is between 19 and 21 degrees.
9. A wind power generation assembly shafting according to claim 5, wherein: the contact angle of the first bearing (5) is between 23 and 25 degrees.
10. A wind power plant comprising a hub (4) and a wind turbine foundation (3), characterized in that it further comprises a wind power plant shaft system arranged between said hub (4) and said wind turbine foundation (3), said wind power plant shaft system being a wind power plant shaft system according to any of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111277281.1A CN113969876B (en) | 2021-10-29 | 2021-10-29 | Wind generating set shafting and wind generating set |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111277281.1A CN113969876B (en) | 2021-10-29 | 2021-10-29 | Wind generating set shafting and wind generating set |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113969876A true CN113969876A (en) | 2022-01-25 |
| CN113969876B CN113969876B (en) | 2023-07-04 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111277281.1A Active CN113969876B (en) | 2021-10-29 | 2021-10-29 | Wind generating set shafting and wind generating set |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008064244A (en) * | 2006-09-08 | 2008-03-21 | Ntn Corp | Spindle supporting structure for wind power generator |
| EP1933027A1 (en) * | 2006-12-08 | 2008-06-18 | Harakosan Co. Ltd. | Hub for the rotor of a wind turbine |
| CN201475161U (en) * | 2009-09-01 | 2010-05-19 | 常州光洋轴承有限公司 | Special bearing for main shaft of direct-drive wind power generating set |
| CN104632880A (en) * | 2013-11-07 | 2015-05-20 | Skf公司 | Bearing arrangement for fluid machinery application |
| WO2016146115A1 (en) * | 2015-03-19 | 2016-09-22 | Schaeffler Technologies AG & Co. KG | Roller bearing, for example of a wind power plant |
| US20180128248A1 (en) * | 2012-08-21 | 2018-05-10 | Aktiebolaget Skf | Wind turbine rotor shaft arrangement |
| CN207349031U (en) * | 2017-10-26 | 2018-05-11 | 新疆金风科技股份有限公司 | The shafting and wind power generating set of wind power generating set |
| WO2018153419A1 (en) * | 2017-02-21 | 2018-08-30 | Vestas Wind Systems A/S | Wind turbine main rotor arrangement having improved bearing abutment configuration |
| WO2021060389A1 (en) * | 2019-09-26 | 2021-04-01 | Ntn株式会社 | Double row tapered roller bearing |
| CN113294443A (en) * | 2021-06-25 | 2021-08-24 | 东方电气集团东方电机有限公司 | Bearing device and wind power generation equipment |
| CN113446173A (en) * | 2021-07-15 | 2021-09-28 | 上海电气风电集团股份有限公司 | Wind generating set and transmission shaft system thereof |
-
2021
- 2021-10-29 CN CN202111277281.1A patent/CN113969876B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008064244A (en) * | 2006-09-08 | 2008-03-21 | Ntn Corp | Spindle supporting structure for wind power generator |
| EP1933027A1 (en) * | 2006-12-08 | 2008-06-18 | Harakosan Co. Ltd. | Hub for the rotor of a wind turbine |
| CN201475161U (en) * | 2009-09-01 | 2010-05-19 | 常州光洋轴承有限公司 | Special bearing for main shaft of direct-drive wind power generating set |
| US20180128248A1 (en) * | 2012-08-21 | 2018-05-10 | Aktiebolaget Skf | Wind turbine rotor shaft arrangement |
| CN104632880A (en) * | 2013-11-07 | 2015-05-20 | Skf公司 | Bearing arrangement for fluid machinery application |
| WO2016146115A1 (en) * | 2015-03-19 | 2016-09-22 | Schaeffler Technologies AG & Co. KG | Roller bearing, for example of a wind power plant |
| WO2018153419A1 (en) * | 2017-02-21 | 2018-08-30 | Vestas Wind Systems A/S | Wind turbine main rotor arrangement having improved bearing abutment configuration |
| CN207349031U (en) * | 2017-10-26 | 2018-05-11 | 新疆金风科技股份有限公司 | The shafting and wind power generating set of wind power generating set |
| WO2021060389A1 (en) * | 2019-09-26 | 2021-04-01 | Ntn株式会社 | Double row tapered roller bearing |
| CN113294443A (en) * | 2021-06-25 | 2021-08-24 | 东方电气集团东方电机有限公司 | Bearing device and wind power generation equipment |
| CN113446173A (en) * | 2021-07-15 | 2021-09-28 | 上海电气风电集团股份有限公司 | Wind generating set and transmission shaft system thereof |
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| Publication number | Publication date |
|---|---|
| CN113969876B (en) | 2023-07-04 |
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Address after: 830026 No. 107, Shanghai Road, Urumqi economic and Technological Development Zone, the Xinjiang Uygur Autonomous Region Patentee after: Jinfeng Technology Co.,Ltd. Address before: 830026 No. 107, Shanghai Road, Urumqi economic and Technological Development Zone, the Xinjiang Uygur Autonomous Region Patentee before: XINJIANG GOLDWIND SCIENCE & TECHNOLOGY Co.,Ltd. |
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