Impeller device of wind turbine generator

Abstract

The impeller device comprises a hub, blades, an inner variable-pitch bearing and an outer variable-pitch bearing, the hub comprises a hub center structure and three bearing seat structures with the same structure, and each bearing seat structure is provided with an inner mounting hole and an outer mounting hole; each blade comprises a blade root and a blade root connecting structure which are connected with each other, each blade root connecting structure comprises a transition section and a connecting section, each transition section gradually contracts and extends inwards from the connecting end face of the corresponding blade root in the radial direction of the impeller, each connecting section is located in the bearing seat structure, and each connecting section is provided with an inner and outer side mounting journal corresponding to the corresponding inner and outer side mounting hole. Outer rings of the inner and outer variable pitch bearings are embedded in the inner and outer mounting holes, and inner rings are sleeved on the inner and outer mounting journals. According to the scheme, the size of each variable-pitch bearing is not limited by the diameter of the root of the blade, the blade root connecting structure with the variable shaft diameter is designed, and the pair of variable-pitch bearings is arranged in the bearing seat structure, so that standardized model selection of the variable-pitch bearings can be realized, and the research and development and production cost is reduced; and the number of bolts and the maintenance cost are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to an impeller device of a wind turbine generator set. Background Art

[0002] In the current new energy field, with the increasing emphasis on clean energy, wind power generation technology continues to develop. Among them, the impeller system, as the core component of the wind turbine, plays a vital role. Its main function is to efficiently capture natural wind energy and convert it into mechanical kinetic energy, which in turn drives the generator to convert it into electrical energy, so as to achieve the effective use of clean energy.

[0003] The impeller system is mainly composed of key components such as blades, hubs, pitch bearings, and pitch bearing connecting bolts. Compared with general-purpose bearings in traditional mechanical equipment, pitch bearings have higher R&D and manufacturing costs due to their highly customized design. In addition, the high failure rate of pitch bearings and the high cost of maintenance and replacement have become key bottlenecks restricting the development of the wind power industry. In addition, the pitch bearing connecting bolts are the second most failed parts in the impeller system. Regular maintenance and replacement of some connecting bolts require high-altitude operations outside the cabin, which is difficult to construct and has poor working conditions.

[0004] In view of this, how to design a new impeller system that can adopt standardized variable pitch bearings and reduce the maintenance cost of bolts has become a technical problem that needs to be urgently solved in the current wind power industry. Summary of the invention

[0005] The purpose of the present invention is to solve the problems existing in the prior art and to provide an impeller device for a wind turbine.

[0006] In order to achieve the above object, the present invention provides an impeller device of a wind turbine generator set, comprising:

[0007] The hub comprises a hub center structure connected to the main shaft and three bearing seat structures of the same structure which are equally spaced and circumferentially distributed around the hub center structure, wherein the bearing seat structure is provided with inner mounting holes and outer mounting holes which are spaced apart in the radial direction of the impeller;

[0008] A blade, comprising a blade root and a blade root connection structure connected to each other, wherein the blade root connection structure comprises a transition section extending gradually inwardly from a connection end surface of the blade root along the impeller radial direction and a connection section located in the bearing seat structure, wherein the connection section is provided with an inner mounting journal corresponding to the inner mounting hole and an outer mounting journal corresponding to the outer mounting hole;

[0009] An inner pitch bearing, whose outer ring is embedded in the inner mounting hole and tightly fits with the inner mounting hole, and whose inner ring is sleeved on the inner mounting journal and tightly fits with the inner mounting journal;

[0010] The outer pitch bearing has an outer ring embedded in the outer mounting hole and tightly matched with the outer mounting hole, and an inner ring sleeved on the outer mounting journal and tightly matched with the outer mounting journal.

[0011] Furthermore, the impeller device also includes a pressure cover, which is connected to the inner end of the blade root connection structure by bolts and abuts against the inner end surface of the inner ring of the inner pitch bearing.

[0012] Furthermore, the connecting section is provided with a step portion abutting against an outer end surface of an inner ring of the outer pitch bearing.

[0013] Furthermore, the step portion is arranged at a position between the outer mounting journal of the connecting section and the transition section.

[0014] Furthermore, the bearing seat structure is provided with an inner step portion adjacent to the inner mounting hole and an outer step portion adjacent to the outer mounting hole, the inner step portion abuts against the outer end surface of the outer ring of the inner pitch bearing, and the outer step portion abuts against the inner end surface of the outer ring of the outer pitch bearing.

[0015] Furthermore, the inner step portion is arranged at a position where the bearing seat structure engages with the hub center structure.

[0016] Furthermore, the size of the inner pitch bearing is smaller than the size of the outer pitch bearing.

[0017] Further, the diameter of the outer mounting journal of the connecting section is greater than the diameter of the inner mounting journal, and the wall thickness at the outer mounting journal is greater than the wall thickness at the inner mounting journal.

[0018] Furthermore, the hub center structure and the bearing seat structure are integrally formed, and the transition section and the connecting section are integrally formed.

[0019] Furthermore, the inner pitch bearing and the outer pitch bearing adopt angular contact ball bearings that match each other.

[0020] The present application scheme arranges a bearing seat structure on the hub and a flange shaft structure at the blade root, so that the size of the variable pitch bearing is no longer limited by the blade root diameter. On the premise of meeting the load requirements, by designing a blade root connection structure with a variable shaft diameter and arranging a pair of variable pitch bearings spaced from each other along the axis direction of the bearing seat structure, it is possible to achieve standardized selection of variable pitch bearings and reduce R&D and production costs; and it is possible to reduce the number of bolts and reduce the maintenance cost of the bolts. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The following drawings of the present invention are used as part of the present invention for understanding the present invention. The drawings show the embodiments of the present invention and their descriptions, and are used to explain the device and principle of the present invention. In the drawings,

[0022] Figure 1 is a schematic diagram of the three-dimensional structure of an impeller device according to an embodiment of the present invention;

[0023] Figure 2 It is a front structural schematic diagram of an impeller device according to an embodiment of the present invention;

[0024] Figure 3 for Figure 2 AA section view in;

[0025] Figure 4 for Figure 3 A partial enlarged view of part B in FIG. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. The described embodiments are only preferred embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be understood that, unless otherwise defined, the technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The purpose of the terms used herein is only to describe specific embodiments and is not intended to limit the present invention. Terms such as "parts" and "pieces" that appear in this article can represent both single parts and combinations of multiple parts. The singular forms of "one", "an" and "said / the" are also intended to include plural forms unless the context clearly indicates otherwise. Ordinal numbers such as "first" and "second" are merely identifiers and do not have any other meaning, such as a specific order, etc. Moreover, for example, the term "first component" itself does not imply the existence of a "second component", and the term "second component" itself does not imply the existence of a "first component". When the terms "comprising" and / or "including" are used in this specification, it indicates the presence of the features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof. The terms "upper", "lower", "front", "back", "left", "right", "inside", "outside", "center", "vertical", "horizontal" and similar expressions are for illustrative purposes only and are not limiting. The terms "connect", "install", "connected", and "set" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be a communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The features described in this document in one embodiment may be applied to another embodiment alone or in combination with other features, unless the feature is not applicable in the other embodiment or otherwise specified.

[0028] Hereinafter, specific embodiments of the present invention will be described in more detail with reference to the accompanying drawings. These drawings show representative embodiments of the present invention and do not limit the present invention.

[0029] The present invention provides an impeller device of a wind turbine generator set, such as Figure 1-4As shown, the impeller device includes a hub 1, blades 2, an inner pitch bearing 3 and an outer pitch bearing 4. The hub 1 includes a hub center structure 11 connected to the main shaft of the unit and three bearing seat structures 12 of the same structure distributed equidistantly along the circumferential direction with the hub center structure 11 as the center. The bearing seat structure 12 extends radially outward from the hub center structure 11 and is provided with inner mounting holes and outer mounting holes spaced apart in the radial direction; the blade 2 includes a blade root 21 and a blade root connection structure 22 connected to each other. The blade root connection structure 22 includes a transition section 221 extending gradually inwardly from the connection end surface of the blade root along the impeller radial direction and a bearing seat located at the bearing seat. The connecting section 222 in the structure 12 is provided with an inner mounting journal corresponding to the inner mounting hole and an outer mounting journal corresponding to the outer mounting hole; the outer ring of the inner variable pitch bearing 3 is embedded in the inner mounting hole and the outer ring surface is tightly matched with the inner mounting hole, the inner ring is sleeved on the inner mounting journal and the inner ring surface is tightly matched with the inner mounting journal; the outer ring of the outer variable pitch bearing 4 is embedded in the outer mounting hole and the outer ring surface is tightly matched with the outer mounting hole, the inner ring is sleeved on the outer mounting journal and the inner ring surface is tightly matched with the outer mounting journal. Preferably, the inner variable pitch bearing 3 and the outer variable pitch bearing 4 use mutually matching angular contact ball bearings, which can simultaneously withstand large radial loads and axial loads, and improve the safety and reliability of the impeller. In order to improve the structural strength and the convenience of production and assembly, the hub center structure 11 and the bearing seat structure 12 are integrally formed, and the transition section 221 of the blade root connection structure 22 is integrally formed with the connecting section 222.

[0030] The hub and blades of traditional wind turbines are connected by a single pitch bearing. The inner ring of the pitch bearing is connected to the blade root flange end face and tightened by bolts, and the outer ring is connected to the hub flange end face and tightened by bolts. Therefore, the size of the pitch bearing is limited by the blade root diameter, and requires customized design and production and is connected by two inner and outer circles of bolts. The present application scheme sets a bearing seat structure on the hub and a flange shaft structure at the blade root, so that the size of the pitch bearing is no longer limited by the blade root diameter. Under the premise of meeting the load requirements, by designing a blade root connection structure with a variable shaft diameter, and setting a pair of pitch bearings spaced apart from each other along the axis direction in the bearing seat structure, the standardized selection of pitch bearings can be achieved, and the R&D and production costs can be reduced; and the number of bolts can be reduced and the maintenance cost of the bolts can be reduced.

[0031] According to an embodiment of the present invention, the impeller device further includes a gland 5. Accordingly, the inner end of the blade root connection structure 22 is set to a flange form with a threaded hole, so that the gland 5 is connected to the inner end of the blade root connection structure 22 by bolts and abuts against the inner end face of the inner ring of the inner pitch bearing 3 to achieve axial preload of the inner pitch bearing 3. Preferably, the connection section 222 of the blade root connection structure passes through the inside of the bearing seat structure 12 and extends into the hub center structure 11, so that the gland 5 is located inside the hub center structure 11, which is convenient for gland installation and subsequent bolt torque maintenance. Compared with the traditional form in which the inner and outer rings of the unit pitch bearing are respectively connected to the hub and the blade by bolts, this solution has advantages in terms of economy and convenience of later maintenance. Corresponding to the gland 5, the connection section 222 is provided with a step portion for abutting against the outer end face of the inner ring of the outer pitch bearing 4, and the step portion is arranged at a position between the outer mounting journal of the connection section 222 and the transition section 221. In addition, the outer side end of the blade root connection structure 22 may be provided with bolt holes distributed along the circumferential direction, so as to form a flange connection with the blade root 21 .

[0032] like Figure 3 and Figure 4 As shown, the bearing seat structure 12 is provided with an inner step portion adjacent to the inner mounting hole and an outer step portion adjacent to the outer mounting hole, the inner step portion abuts against the outer end surface of the outer ring of the inner pitch bearing 3, and the outer step portion abuts against the inner end surface of the outer ring of the outer pitch bearing 4. The inner step portion is provided at a position where the bearing seat structure 12 is engaged with the hub center structure 11.

[0033] Based on the load analysis of the inner pitch bearing 3 and the outer pitch bearing 4 under various working conditions, and combined with the compact design of the integral impeller device, the size of the inner pitch bearing 3 is designed to be smaller than the size of the outer pitch bearing 4. Accordingly, the diameter of the outer mounting journal of the connecting section 222 is larger than the diameter of the inner mounting journal, and the wall thickness at the outer mounting journal is larger than the wall thickness at the inner mounting journal. Figure 3 and Figure 4 As shown, the connection section 222 and the bearing seat structure 12 each include at least one section that shrinks inwardly along the impeller radial direction, so as to realize the differentiated design of the inner and outer pitch bearing sizes. In addition, the maximum diameter of the bearing seat structure 12 is smaller than the diameter of the joint end surface of the blade root 21 and the blade root connection structure 22, so as to realize the compact and lightweight design of the hub; as mentioned above, since the bearing seat structure 12 includes at least one section that shrinks inwardly along the impeller radial direction, the size of the hub center structure 11 is greatly reduced compared with the conventional unit hub connected with blades of the same size.

[0034] The present invention has been described through the above-mentioned embodiments, but it should be understood that the above-mentioned embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present invention is not limited to the above-mentioned embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of the protection claimed by the present invention. The protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. An impeller device of a wind turbine generator set, characterized in that: include: A wheel hub (1) comprises a wheel hub center structure (11) connected to a main shaft and three bearing seat structures (12) of the same structure which are equally spaced and circumferentially distributed around the wheel hub center structure (11), wherein the bearing seat structure (12) is provided with an inner mounting hole and an outer mounting hole which are spaced apart in the radial direction of the impeller; A blade (2), comprising a blade root (21) and a blade root connection structure (22) connected to each other, the blade root connection structure (22) comprising a transition section (221) extending gradually inwardly along the impeller radial direction from a connection end surface of the blade root, and a connection section (222) located in the bearing seat structure (12), the connection section (222) being provided with an inner mounting shaft neck corresponding to the inner mounting hole and an outer mounting shaft neck corresponding to the outer mounting hole; An inner pitch bearing (3), the outer ring of which is embedded in the inner mounting hole and tightly matched with the inner mounting hole, and the inner ring of which is sleeved on the inner mounting journal and tightly matched with the inner mounting journal; An outer variable pitch bearing (4) has an outer ring embedded in the outer mounting hole and tightly fitted with the outer mounting hole, and an inner ring sleeved on the outer mounting shaft neck and tightly fitted with the outer mounting shaft neck.

2. The impeller device according to claim 1, characterized in that: The impeller device also includes a pressure cover (5), which is connected to the inner end of the blade root connection structure (22) by bolts and abuts against the inner end surface of the inner ring of the inner pitch bearing (3).

3. The impeller device according to claim 1, characterized in that: The connecting section (222) is provided with a step portion that abuts against the outer end surface of the inner ring of the outer pitch bearing (4).

4. The impeller device according to claim 3, characterized in that: The step portion is arranged at a position between the outer mounting journal of the connecting section (222) and the transition section (221).

5. The impeller device according to claim 1, characterized in that: The bearing seat structure (12) is provided with an inner step portion adjacent to the inner mounting hole and an outer step portion adjacent to the outer mounting hole, the inner step portion abuts against the outer end surface of the outer ring of the inner pitch bearing (3), and the outer step portion abuts against the inner end surface of the outer ring of the outer pitch bearing (4).

6. The impeller device according to claim 5, characterized in that The inner step portion is arranged at a position of the bearing seat structure (12) that is engaged with the hub center structure (11).

7. The impeller device according to claim 1, characterized in that The size of the inner pitch bearing (3) is smaller than the size of the outer pitch bearing (4).

8. The impeller device according to claim 1, characterized in that The diameter of the outer mounting journal of the connecting section (222) is greater than the diameter of the inner mounting journal, and the wall thickness at the outer mounting journal is greater than the wall thickness at the inner mounting journal.

9. The impeller device according to claim 1, characterized in that: The hub center structure (11) and the bearing seat structure (12) are integrally formed, and the transition section (221) and the connecting section (222) are integrally formed.

10. The impeller device according to any one of claims 1 to 9, characterized in that: The inner variable pitch bearing (3) and the outer variable pitch bearing (4) adopt angular contact ball bearings that match each other.

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