CN110778455A - Variable pitch connecting structure of wind generating set - Google Patents
Variable pitch connecting structure of wind generating set Download PDFInfo
- Publication number
- CN110778455A CN110778455A CN201911264431.8A CN201911264431A CN110778455A CN 110778455 A CN110778455 A CN 110778455A CN 201911264431 A CN201911264431 A CN 201911264431A CN 110778455 A CN110778455 A CN 110778455A
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- Prior art keywords
- variable
- flanges
- pitch bearing
- elastic mechanism
- variable pitch
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- 239000007769 metal material Substances 0.000 claims description 3
- 239000002861 polymer material Substances 0.000 claims description 3
- 239000005060 rubber Substances 0.000 claims description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
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Classifications
-
- 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
- F03D7/00—Controlling wind motors
- F03D7/02—Controlling wind motors the wind motors having rotation axis substantially parallel to the air flow entering the rotor
- F03D7/022—Adjusting aerodynamic properties of the blades
- F03D7/0224—Adjusting blade pitch
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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
- F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor
- F03D1/06—Rotors
- F03D1/065—Rotors characterised by their construction elements
- F03D1/0658—Arrangements for fixing wind-engaging parts to a hub
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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
- F03D13/00—Assembly, mounting or commissioning of wind motors; Arrangements specially adapted for transporting wind motor components
- F03D13/10—Assembly of wind motors; Arrangements for erecting wind motors
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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)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Wind Motors (AREA)
Abstract
The invention discloses a variable pitch connecting structure of a wind generating set, which comprises a hub, a variable pitch bearing and blades; the method is characterized in that: the outer ring or the inner ring of the variable-pitch bearing is connected with the hub through a bolt group; the inner ring or the outer ring of the variable-pitch bearing is connected with one end of the elastic mechanism through a bolt group; the other end of the elastic mechanism is connected with the blade through a bolt group; the elastic mechanism enables the blade to be twisted relative to the inner ring or the outer ring of the variable-pitch bearing connected with the blade and reset. The invention has simple structure and low cost, and the variable-pitch bearing and the blades are indirectly connected through the elastic mechanism, so that the blades and the outer ring or the inner ring of the variable-pitch bearing connected with the blades can be twisted relatively under the action of wind load, and the flexibility of the system is increased; the load of the variable pitch component is smaller and smoother under extreme working conditions, and the reliability of the wind generating set is improved.
Description
Technical Field
The invention relates to the technical field of wind driven generators, in particular to a variable pitch connecting structure of a wind generating set.
Background
A variable pitch device of a wind generating set is an important component of the wind generating set and comprises a hub, a variable pitch bearing and blades. The variable-pitch device of the large-megawatt wind generating set is generally provided with a variable-pitch gear on a fixed variable-pitch bearing inner ring or a fixed variable-pitch bearing outer ring, when the wind load is larger, the variable-pitch gear mounted on a hub drives a variable-pitch bearing and blades to rotate in a gear meshing mode, so that the aerodynamic load is reduced through the change of the attack angle of the blades, and the safe and reliable operation of the wind generating set is ensured.
A traditional wind generating set variable pitch connecting structure is shown in figure 1, an outer ring 2-1 of a variable pitch bearing 2 is fixedly connected with a hub 1 through a bolt group 11, and an inner ring 2-2 of the variable pitch bearing is fixedly connected with blades 4 through a bolt group 12. The variable-pitch connecting structure has more than 10 years of application experience on a wind power large megawatt unit, and has the advantage of high reliability of a transmission structure. But along with the impeller diameter is constantly increaseed, fan operating mode is more and more abominable, and the following drawback of this structure is prominent day by day:
1. during power generation, a variable pitch motor is locked, and blades and a hub are rigidly connected, so that when wind load is large, a variable pitch system directly bears large energy impact, and a variable pitch bearing and the blades bear excessive load and impact, so that a variable pitch component is damaged too early;
2. when the pitch is changed, the load fluctuation borne by the pitch motor is large, the pitch change in the early stage is slow, the pitch change in the later stage is too fast, and the damage of a pitch change component is accelerated;
3. under extreme conditions, the load is large, and the blade is easily blown open, leads to three blade angle differences huge, produces very big extra aerodynamic unbalance load to make the oar part become the premature failure.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a variable pitch connecting structure of a wind generating set, which has a simple structure and low cost, wherein blades of the variable pitch connecting structure are connected with a variable pitch bearing through a flexible structure, the blades absorb extreme wind load energy through torsion during high load, and simultaneously have a self-resetting function during low load, thereby being beneficial to the load stability of variable pitch of a motor; and the condition that the three blades are asynchronous under the extreme wind condition can be effectively relieved, and the pneumatic unbalanced load is reduced.
The technical scheme adopted by the invention is as follows: a variable pitch connecting structure of a wind generating set comprises a hub, a variable pitch bearing, an elastic mechanism and blades; the outer ring or the inner ring of the variable-pitch bearing is connected with the hub through a bolt group; when the outer ring of the variable pitch bearing is connected with the hub, the inner ring of the variable pitch bearing is connected with one end of the elastic mechanism through the bolt group, and when the inner ring of the variable pitch bearing is connected with the hub, the outer ring of the variable pitch bearing is connected with one end of the elastic mechanism through the bolt group; the other end of the elastic mechanism is connected with the blade through a bolt group; the elastic mechanism enables the blade to be twisted relative to the inner ring or the outer ring of the variable-pitch bearing connected with the blade and reset.
In the pitch-controlled connecting structure of the wind generating set, the elastic mechanism comprises two flanges and a connecting cylinder, the two flanges are coaxially arranged, the two flanges are connected through the connecting cylinder and a plurality of rib plates, the flanges are coaxial with the connecting cylinder, the plurality of rib plates are uniformly arranged along the circumferential direction, two ends of each rib plate are respectively connected with the two flanges, and the inner side surfaces of the rib plates are connected with the outer cylindrical surface of the connecting cylinder; the two flanges are respectively connected with the variable pitch bearing and the blade.
In the pitch-variable connecting structure of the wind generating set, the connecting cylinder and the rib plate are made of high polymer materials, rubber or metal materials.
In the pitch-variable connecting structure of the wind generating set, the elastic mechanism comprises two flanges and a corrugated pipe, and the two flanges are connected through a plurality of double-end studs; two ends of the corrugated pipe are respectively connected with the two flanges; the two flanges are respectively connected with the variable pitch bearing and the blade.
In the pitch-variable connecting structure of the wind generating set, the outer cylindrical surface of the flange is provided with the plurality of connecting lugs, the plurality of connecting lugs are uniformly arranged along the circumferential direction, the connecting lugs are provided with the bolt holes, the stud penetrates through the bolt holes of the connecting lugs and is fixed through the two nuts, and the two nuts are respectively positioned on two sides of the connecting lugs.
Compared with the prior art, the invention has the beneficial effects that: the invention has simple structure and low cost, and the variable-pitch bearing and the blades are indirectly connected through the elastic mechanism, so that the blades and the outer ring or the inner ring of the variable-pitch bearing connected with the blades can be twisted relatively under the action of wind load, and the flexibility of the system is increased; under extreme working conditions, the load of the variable-pitch component is smaller and smoother, and the reliability of the wind generating set is improved.
Drawings
FIG. 1 is a schematic view of a conventional pitch connection structure.
Fig. 2 is a schematic structural diagram of embodiment 1 of the present invention.
Fig. 3 is a schematic view of embodiment 1 of the elastic mechanism of the present invention.
Fig. 4 is a schematic view of embodiment 2 of the elastic mechanism of the present invention.
Fig. 5 is a schematic structural diagram of embodiment 2 of the present invention.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in fig. 2, the present invention comprises a hub 1, a pitch bearing 2, a resilient mechanism 3 and a blade 4. The outer ring 2-1 of the variable pitch bearing 2 is fixedly connected with the hub 1 through a bolt group 11, and the inner ring 2-2 of the variable pitch bearing 2 is fixedly connected with one end of the elastic mechanism 3 through a bolt group 12. A connection structure as shown in fig. 5 may also be employed: the inner ring 2-2 of the variable-pitch bearing 2 is fixedly connected with the hub 1 through a bolt group 11; an outer ring 2-1 of the variable pitch bearing 2 is fixedly connected with one end of the elastic mechanism 3 through a bolt group 12. The middle of the variable-pitch bearing 2 is provided with a rolling body 2-3, so that the outer ring 2-1 and the inner ring 2-2 can relatively rotate under the action of load. The other end of the elastic mechanism 3 is fixedly connected with the blade 4 through a bolt group 13.
The elastic mechanism 3 is a flexible structure, and two ends of the elastic mechanism are respectively provided with a flange 31 for connecting with the variable pitch bearing 2 and the blade 4. The elastic mechanism 3 has high axial rigidity and less deformation under the action of wind load; the torsional rigidity is relatively small, the torsion can be realized under a large wind load, and the automatic torsion resetting is realized under a small wind load.
As shown in fig. 3, the elastic mechanism 3 includes two flanges 31 and a connecting cylinder 32, the two flanges 31 are coaxially disposed, the two flanges 31 are connected by the connecting cylinder 32 and a plurality of ribs 33, and the flanges 31 are coaxial with the connecting cylinder 32. The rib plates 33 are uniformly arranged along the circumferential direction, two ends of each rib plate 33 are respectively connected with the two flanges 31, and the inner side surfaces of the rib plates 33 are connected with the outer cylindrical surface of the connecting cylinder 32. Two flanges 31 are connected to the pitch bearing 2 and the blade 4, respectively. The connecting cylinder 32 and the rib plate 33 are made of high polymer materials, rubber or metal materials. The elastic mechanism 3 has a large axial rigidity and is difficult to be stretched and compressed. On the other hand, the elastic mechanism 3 has a weak torque rigidity, so that when the elastic mechanism 3 is subjected to torsional external load, the elastic mechanism 3 can be twisted under a large load, and can be automatically twisted and reset under a small load.
The elastic means 3 may also adopt the structure shown in fig. 4. As shown in fig. 4, the elastic mechanism 3 includes two flanges 31 and a corrugated tube 34, the two flanges 31 are coaxially disposed, the two flanges 31 are connected by a plurality of studs 35, and the plurality of studs are uniformly arranged along a circumferential direction. The flange 31 is provided with four engaging lugs 311 on the outer cylindrical surface (the number of the engaging lugs 311 is not limited to four, and may be less than four, at least two, or may be more than four.), the four engaging lugs 311 are uniformly arranged along the circumferential direction, the engaging lugs 311 are provided with bolt holes, the stud 35 passes through the bolt holes of the engaging lugs 311, and is fixed by two nuts 36, and the two nuts 36 are respectively located on two sides of the engaging lugs 311. Two ends of the corrugated pipe are respectively connected with the two flanges, and the corrugated pipe is coaxial with the flanges; two flanges 31 are connected to the pitch bearing 2 and the blade 4, respectively. The two flanges 31 are fixedly connected by four studs 35 and nuts 36, and have high axial rigidity, so that the flanges are difficult to deform in the axial direction. While the bellows 34 makes the torsion stiffness of the elastic means 3 smaller.
Claims (5)
1. A variable pitch connecting structure of a wind generating set comprises a hub, a variable pitch bearing and blades; the method is characterized in that: the outer ring or the inner ring of the variable-pitch bearing is connected with the hub through a bolt group; when the outer ring of the variable pitch bearing is connected with the hub, the inner ring of the variable pitch bearing is connected with one end of the elastic mechanism through the bolt group, and when the inner ring of the variable pitch bearing is connected with the hub, the outer ring of the variable pitch bearing is connected with one end of the elastic mechanism through the bolt group; the other end of the elastic mechanism is connected with the blade through a bolt group; the elastic mechanism enables the blade to be twisted relative to the inner ring or the outer ring of the variable-pitch bearing connected with the blade and reset.
2. A wind generating set pitch connection structure according to claim 1, wherein: the elastic mechanism comprises two flanges and a connecting cylinder, the two flanges are coaxially arranged, the two flanges are connected through the connecting cylinder and a plurality of rib plates, the flanges are coaxial with the connecting cylinder, the plurality of rib plates are uniformly arranged along the circumferential direction, two ends of each rib plate are respectively connected with the two flanges, and the inner side surfaces of the rib plates are connected with the outer cylindrical surface of the connecting cylinder; the two flanges are respectively connected with the variable pitch bearing and the blade.
3. A wind generating set pitch connection structure according to claim 2, wherein: the connecting cylinder and the rib plate are made of high polymer materials, rubber or metal materials.
4. A wind generating set pitch connection structure according to claim 1, wherein: the elastic mechanism comprises two flanges and a corrugated pipe, and the two flanges are connected through a plurality of double-end studs; two ends of the corrugated pipe are respectively connected with the two flanges; the two flanges are respectively connected with the variable pitch bearing and the blade.
5. A wind generating set pitch connection structure according to claim 4, wherein: the outer face of cylinder of flange on be equipped with a plurality of engaging lugs, a plurality of engaging lugs evenly arrange along the circumferencial direction, are equipped with the bolt hole on the engaging lug, stud pass the bolt hole of engaging lug, it is fixed through two nuts, two nuts are located the both sides of engaging lug respectively.
Priority Applications (1)
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CN201911264431.8A CN110778455B (en) | 2019-12-11 | 2019-12-11 | Variable pitch connecting structure of wind generating set |
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CN201911264431.8A CN110778455B (en) | 2019-12-11 | 2019-12-11 | Variable pitch connecting structure of wind generating set |
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CN110778455A true CN110778455A (en) | 2020-02-11 |
CN110778455B CN110778455B (en) | 2021-06-29 |
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CN201911264431.8A Active CN110778455B (en) | 2019-12-11 | 2019-12-11 | Variable pitch connecting structure of wind generating set |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111963392A (en) * | 2020-07-22 | 2020-11-20 | 明阳智慧能源集团股份公司 | Method for solving zero tooth abrasion of variable pitch bearing of wind generating set |
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