CN110778455A - A wind turbine pitch connection structure - Google Patents

Abstract

The invention discloses a pitch connection structure of a wind turbine, comprising a hub, a pitch bearing and blades; it is characterized in that it further comprises an elastic mechanism, and the outer ring or the inner ring of the pitch bearing is connected with the wheel hub through a bolt group; The inner ring or outer ring of the paddle 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 the bolt group; the elastic mechanism enables the blade to be relative to the inner ring or outer ring of the pitch bearing connected to it. The loop twists and can be reset. The invention has simple structure and low cost, and the pitch bearing and the blade are indirectly connected by an elastic mechanism, so that relative torsion can occur between the blade and the outer ring or the inner ring of the pitch bearing connected to it under the action of wind load, The system flexibility is increased; the load of the pitch components is smaller and smoother under extreme working conditions, and the reliability of the wind turbine is improved.

Description

A wind turbine pitch connection structure

technical field

The invention relates to the technical field of wind power generators, in particular to a pitch connection structure of a wind power generator set.

Background technique

The wind turbine pitch device is an important part of the wind turbine, consisting of the hub, the pitch bearing and the blades. The pitch device of the large megawatt wind turbine is usually provided with a pitch gear on the inner ring of the fixed pitch bearing or the outer ring of the fixed pitch bearing. When the wind load is large, it is driven by the pitch mounted on the hub. , drive the pitch bearing and the blade to rotate in the way of gear meshing, so as to reduce the aerodynamic load by changing the angle of attack of the blade, and ensure the safe and reliable operation of the wind turbine.

The traditional wind turbine pitch connection structure is shown in Figure 1. The outer ring 2-1 of the pitch bearing 2 is connected and fixed with the hub 1 through the bolt group 11, while the inner ring 2-2 of the pitch bearing is connected by the bolt group 12 and the blade 4. Connection is fixed. The pitch connection structure has more than 10 years of application experience in wind power large-megawatt units, and has the advantages of high reliability of the transmission structure. However, as the diameter of the impeller continues to increase, the working conditions of the fan are getting worse and worse, and the following drawbacks of this structure are becoming increasingly prominent:

1. When generating power, the pitch motor is locked, and there is a rigid connection between the blade and the hub, which makes the pitch system directly bear a larger energy impact when the wind load is large, which causes the pitch bearing and blade to be overburdened. High loads and shocks, leading to premature failure of pitch components;

2. When pitching, the pitch motor is subject to large load fluctuations, which is prone to slow pitching in the early stage and too fast pitching in the later stage, which accelerates the damage to the pitching components;

3. Under extreme working conditions, the load is large and the blades are easily blown apart, resulting in a huge difference in the blade angles of the three blades, resulting in a very large additional aerodynamic unbalanced load, resulting in premature failure of the pitch components.

SUMMARY OF THE INVENTION

In order to solve the problems existing in the prior art, the present invention provides a wind turbine pitch connection structure with simple structure and low cost. Absorb the extreme energy of wind load, and at the same time at low load, it has a self-reset function, which helps the load stability of the motor pitch; and it can effectively alleviate the asynchronous situation of the three blades under extreme wind conditions, reducing the aerodynamic unbalanced load .

The technical scheme adopted in the present invention is as follows: a pitch connection structure of a wind turbine, including a hub, a pitch bearing, an elastic mechanism and blades; an outer ring or an inner ring of the pitch bearing is connected to the wheel hub through a bolt group; When the outer ring of the bearing is connected with the hub, the inner ring of the pitch bearing is connected with one end of the elastic mechanism through the bolt group. When the inner ring of the pitch bearing is connected with the hub, the outer ring of the 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 and reset relative to the inner or outer ring of the pitch bearing connected to it.

In the above-mentioned wind turbine pitch connection structure, the elastic mechanism includes two flanges and a connecting cylinder, the two flanges are coaxially arranged, and the two flanges are connected by a connecting cylinder and a plurality of rib plates, and the flanges are connected with each other. Coaxial with the connecting cylinder, a plurality of rib plates are evenly arranged along the circumferential direction, the two ends of the rib plate are respectively connected with two flanges, the inner side of the rib plate is connected with the outer cylindrical surface of the connecting cylinder; the two flanges are respectively connected with the pitch Bearing and blade connection.

In the above-mentioned variable-pitch connection structure of the wind turbine, the connection cylinder and the rib are made of polymer material, rubber or metal material.

In the above-mentioned wind turbine pitch connection structure, the elastic mechanism includes two flanges and a corrugated pipe, and the two flanges are connected by a plurality of double-ended studs; the two ends of the corrugated pipe are respectively connected to the two flanges. One flange connection; two flanges are respectively connected with the pitch bearing and the blade.

In the above-mentioned wind turbine pitch connection structure, the outer cylindrical surface of the flange is provided with a plurality of connection ears, the plurality of connection ears are evenly arranged along the circumferential direction, and the connection ears are provided with bolt holes, and the double connection ears are provided with bolt holes. The head stud passes through the bolt hole of the connecting ear, and is fixed by two nuts, and the two nuts are respectively located on both sides of the connecting ear.

Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention has a simple structure and low cost, and the pitch bearing and the blade are indirectly connected by an elastic mechanism, so that the outer ring or the outer ring or the outer ring of the pitch bearing connected to the blade is connected with it. Relative torsion can occur between the inner rings under the action of wind load, which increases the flexibility of the system; this makes the load of the pitch components smaller and gentler under extreme working conditions, which improves the reliability of the wind turbine.

Description of drawings

FIG. 1 is a schematic diagram of an existing pitch connection structure.

FIG. 2 is a schematic structural diagram of Embodiment 1 of the present invention.

FIG. 3 is a schematic diagram of Embodiment 1 of the elastic mechanism of the present invention.

FIG. 4 is a schematic diagram 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 ways

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in FIG. 2 , the present invention includes a hub 1 , a pitch bearing 2 , an elastic mechanism 3 and a blade 4 . The outer ring 2-1 of the pitch bearing 2 is fixedly connected to the hub 1 through the bolt group 11, and the inner ring 2-2 of the pitch bearing 2 is fixedly connected to one end of the elastic mechanism 3 through the bolt group 12. The connection structure shown in Figure 5 can also be used: the inner ring 2-2 of the pitch bearing 2 is fixedly connected to the wheel hub 1 through the bolt group 11; the outer ring 2-1 of the pitch bearing 2 is connected by the bolt group 12 and the elastic mechanism 3. fixed connection at one end. The pitch bearing 2 is provided with rolling elements 2-3 in the middle, so that the outer ring 2-1 and the inner ring 2-2 can rotate relative to each other under the action of the load. The other end of the elastic mechanism 3 is connected and fixed with the blade 4 through the bolt group 13 .

The elastic mechanism 3 is a flexible structure, and its two ends are respectively provided with a flange 31 for connecting with the 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, which can realize torsion under large wind load, and automatically twist and reset under 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 arranged, and the two flanges 31 are connected by a connecting cylinder 32 and a plurality of ribs 33 , The flange 31 is coaxial with the connecting cylinder 32 . The plurality of rib plates 33 are evenly arranged along the circumferential direction, two ends of the rib plates 33 are respectively connected with the two flanges 31 , and the inner surface of the rib plates 33 is connected with the outer cylindrical surface of the connecting cylinder 32 . The two flanges 31 are respectively connected with the pitch bearing 2 and the blade 4 . The connecting cylinder 32 and the rib plate 33 are made of polymer material, rubber or metal material. The axial rigidity of the elastic mechanism 3 is large, and it is difficult to be stretched and compressed. On the other hand, the elastic mechanism 3 has relatively weak torque stiffness, so that when subjected to external torsional load, the elastic mechanism 3 will twist under a large load, and automatically twist and reset under a small load.

The elastic mechanism 3 can also adopt the structure shown in FIG. 4 . As shown in FIG. 4 , the elastic mechanism 3 includes two flanges 31 and a bellows 34 , the two flanges 31 are coaxially arranged, and the two flanges 31 are connected by a plurality of studs 35 , a plurality of studs are evenly arranged in the circumferential direction. The outer cylindrical surface of the flange 31 is provided with four connecting ears 311 (the number of connecting ears 311 is not limited to four, it can be less than four, at least two, or more than four.), four The connecting ears 311 are evenly arranged in the circumferential direction, and the connecting ears 311 are provided with bolt holes. The double-ended studs 35 pass through the bolt holes of the connecting ears 311 and are fixed by two nuts 36. The two nuts 36 are respectively located in the connecting ears. Both sides of the 311. The two ends of the bellows are respectively connected with two flanges, and the bellows and the flanges are coaxial; the two flanges 31 are respectively connected with the pitch bearing 2 and the blade 4 . The two flanges 31 are fixedly connected by four studs 35 and nuts 36, and the axial rigidity is large, which makes it difficult to deform in the axial direction. On the other hand, the bellows 34 makes the torsional rigidity of the elastic mechanism 3 smaller.

Claims (5)

1. a wind turbine pitch connection structure, comprising hub, pitch bearing and blade; it is characterized in that: also comprise elastic mechanism, the outer ring or inner ring of described pitch bearing is connected by bolt group and wheel hub; pitch When the outer ring of the bearing is connected with the hub, the inner ring of the pitch bearing is connected with one end of the elastic mechanism through the bolt group. When the inner ring of the pitch bearing is connected with the hub, the outer ring of the 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 and reset relative to the inner or outer ring of the pitch bearing connected to it. 2. The pitch connection structure of the wind turbine according to claim 1, wherein the elastic mechanism comprises two flanges and a connecting cylinder, the two flanges are coaxially arranged, and the two flanges are connected by The tube is connected with a plurality of rib plates, the flange is coaxial with the connecting tube, the plurality of rib plates are evenly arranged along the circumferential direction, the two ends of the rib plate are respectively connected with two flanges, and the inner side of the rib plate is connected with the outer cylindrical surface of the connecting tube. Connection; two flanges are connected to the pitch bearing and the blade respectively. 3 . The pitch connection structure for wind turbines according to claim 2 , wherein the connecting cylinder and the ribs are made of polymer material, rubber or metal material. 4 . 4. The pitch connection structure for wind turbines according to claim 1, wherein the elastic mechanism comprises two flanges and a corrugated pipe, and the two flanges are connected by a plurality of double-ended studs; The two ends of the bellows are respectively connected with two flanges; the two flanges are respectively connected with the pitch bearing and the blades. 5. The pitch connection structure for wind turbines according to claim 4, characterized in that: the outer cylindrical surface of the flange is provided with a plurality of connection ears, the plurality of connection ears are evenly arranged along the circumferential direction, and the connection ears Bolt holes are provided on the studs, and the double-ended studs pass through the bolt holes of the connecting ears and are fixed by two nuts, which are respectively located on both sides of the connecting ears.

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