CN111322201A

CN111322201A - Direct-drive wind generating set

Info

Publication number: CN111322201A
Application number: CN201811526110.6A
Authority: CN
Inventors: 刘勇; 于晨光; 赵兴胜
Original assignee: Jiangsu Goldwind Science and Technology Co Ltd
Current assignee: Jiangsu Goldwind Science and Technology Co Ltd
Priority date: 2018-12-13
Filing date: 2018-12-13
Publication date: 2020-06-23
Anticipated expiration: 2038-12-13
Also published as: CN111322201B

Abstract

The invention provides a direct-drive wind generating set. The direct-drive wind generating set comprises: the generator comprises a hub, a plurality of generators, a main shaft and a main shaft bearing, wherein the hub is rotatably arranged on the main shaft through the main shaft bearing, the hub forms a generator outer shell of the generators, and the generators are arranged in the generator outer shell in parallel. According to the direct-drive wind generating set, the generator can be arranged in the hub, so that the number of parts for connecting the generator and the hub is reduced, a transmission chain is shortened, the transmission efficiency is improved, and the reliability and the economy of a product are improved.

Description

Direct-drive wind generating set

Technical Field

The invention relates to the technical field of wind generating sets, in particular to a direct-drive wind generating set.

Background

With the rapid development of the wind power industry, the horizontal axis direct drive type wind generating set is widely applied in the field of wind power. The conventional structure of the wind generating set is that a hub for mounting the blades and a direct-drive generating set are separately designed, and the hub is mostly in a star-shaped or spherical structure. The hub and the generator are of two independent split structures, the hub is connected with the generator rotor through the main shaft, and mechanical energy is transmitted from the impeller to the generator rotor, so that power generation is performed.

However, the wind generating set with such a structure has the following disadvantages: (1) the generator and the hub are designed in a split mode, the rotor is connected with the hub through the main shaft, the length of the main shaft is long, the kinetic energy transmission chain is too long, and the transmission efficiency is low; (2) the distance between the hub and the cabin base serving as a supporting point is long, and the stability is poor; (3) the connection between the rotor and the hub can be realized only by connecting a plurality of parts for many times, and the structure is complex, the maintenance-free performance is insufficient, and the reliability is poor; (4) the assembly process of the hub and the power generation and the assembly process of the generator and the main frame are complex, the installation process is complicated, and the process feasibility is poor; (5) the split hub and generator rotor support structure has larger body, non-compact structure, more steel consumption and high cost; the generator and the hub are assembled in a split mode, transportation cost is overlapped, and economy is poor.

Disclosure of Invention

The embodiment of the invention provides a technical scheme for integrating a generator rotor mounting shell and a hub, which aims to overcome the defects of a wind generating set in the prior art.

According to an aspect of the present invention, there is provided a direct drive wind turbine generator system, including: a hub rotatably mounted on the main shaft by the main shaft bearing, the hub forming a generator housing for the plurality of generators, the plurality of generators being mounted in parallel within the generator housing.

According to an aspect of the present invention, the hub may include a disk-shaped spoke portion and an outer flange, and the outer flange may extend a predetermined length in an axial direction from an outer circumference of the spoke portion to form the generator outer case.

According to an aspect of the present invention, a main shaft bearing mounting portion is formed at a middle portion of the spoke portion, a bearing outer race of the main shaft bearing is closely fitted to the main shaft bearing mounting portion, a bearing inner race of the main shaft bearing is closely fitted to the main shaft, and stators and rotors of the plurality of generators are located between the outer flange and the main shaft.

According to an aspect of the invention, the plurality of generators are located on both sides of the spoke portion or on the same side of the spoke portion.

According to an aspect of the invention, the hub further includes at least two blade mounting flanges formed on an outer circumference of the spoke portion, the blade mounting flanges protruding outward by a predetermined length with respect to the outer flange in a radial direction of the spoke portion.

According to one aspect of the invention, at least one blade variable pitch device mounting part is formed on the inner side or the outer side of the blade mounting flange, the flange end face of the blade mounting flange inclines towards the front of the hub by a preset angle, and at least one lightening hole is formed in the spoke part.

According to an aspect of the present invention, a through hole is formed at a middle portion of the spoke portion, the spindle bearing mounting portion is an inner flange extending in an axial direction from the through hole, and an axial thickness of the spindle bearing mounting portion is greater than an axial thickness of the spoke portion.

According to an aspect of the invention, the wind turbine further comprises a nacelle mounted on a front side of the hub, and a diameter of the nacelle is smaller than a diameter of the hub.

According to an aspect of the invention, the wind turbine further includes a nacelle cover mounted on a rear side of the hub, a diameter of a portion of the nacelle cover connected to the hub being smaller than a diameter of the hub.

According to an aspect of the present invention, the plurality of generators includes a first generator mounted at a rear side of the spoke portion and a second generator mounted at a front side of the spoke portion.

According to the technical scheme of the invention, the hub is designed to be provided with the concave cylindrical space for mounting the generator rotor, so that the number of parts for connecting the generator and the hub can be greatly reduced, and the reliability and the economical efficiency of a product are improved.

Drawings

The above and other objects and features of the present invention will become more apparent from the following detailed description of the embodiments of the present invention with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a hub according to an embodiment of the present invention;

FIG. 2 is a front view of a hub according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view taken along line A-A in FIG. 2;

FIG. 4 shows a schematic cross-sectional view of a generator built into a hub;

FIG. 5 shows a cross-sectional view of two generators provided in the hub;

FIG. 6 shows a schematic cross-sectional view of a generator base formed as a unitary structure with a main shaft;

FIG. 7 illustrates a perspective view of a hub of a built-in generator mounted with a generator mount according to an exemplary embodiment of the present invention;

FIG. 8 shows a cross-sectional view of a nacelle portion of a wind park according to an embodiment of the invention, wherein a hub is employed;

fig. 9 shows a perspective view of a nacelle part of a wind park according to an embodiment of the invention.

Detailed Description

The embodiment of the invention provides a technical scheme for integrally designing a hub and a generator shell. The generator housing is formed by a hub, and a rotor of the generator is mounted on the generator housing formed by the hub. Through in with the built-in wheel hub of generator, greatly reduced the quantity of connecting piece and the volume, weight and the cost of generating set. Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in fig. 1 to 3, a wheel hub 100 according to an embodiment of the present invention is generally disc-shaped, and includes a disc-shaped spoke portion 10, an outer flange 20 formed on an outer circumference of the spoke portion 10, the outer flange 20 extending a predetermined length in an axial direction of the wheel hub 100 to form a generator outer housing. Specifically, the outer flange 20 extends a predetermined length in the axial direction from the outer edge of the spoke portion 10, thereby forming a cylindrical accommodation chamber in which the generator can be built. The inner circumferential surface of the outer flange 20 may serve as a generator rotor mounting surface, thereby enabling the rotor of the generator to be mounted directly to the hub 100 or to the hub 100 via a rotor bracket. Alternatively, the rotor may be mounted outside the stator, and thus, in an embodiment of the present invention, the generator outer rotor mounting case is formed using the hub 100, and the outer rotor of the generator is mounted on the hub 100.

The outer flange 20 may extend a predetermined length in an axial direction with respect to the spoke portion 10 toward the rear of the hub 100 (i.e., a side facing the generator base), thereby forming a receiving cavity at the rear side of the hub 100. The outer flange 20 may also extend a predetermined length in the axial direction toward the front of the hub 100 with respect to the spoke portion 10, thereby forming a receiving cavity at the front side of the hub 100. Therefore, in the case of installing one generator, the generator may be installed at the front side of the spoke portion 10 or at the rear side of the spoke portion 10.

As shown in fig. 3, at least two generators may be installed in the hub 100 according to an embodiment of the present invention. Accordingly, a receiving cavity for receiving at least two generators may be formed in the hub 100. In the case of mounting two generators, a first accommodation chamber 21 may be formed at the rear side of spoke portion 10 and a second accommodation chamber 22 may be formed at the front side of spoke portion 10, respectively. The first generator may be installed in the first accommodation chamber 21, the second generator may be installed in the second accommodation chamber 22, and the circuits of the two generators may be connected in parallel or in series.

As shown in fig. 3 to 5, the spoke portion 10 is formed at a middle portion thereof with a main shaft bearing mounting portion 11 for cooperating with a main shaft 40 of the generator through a main shaft bearing 41 such that the hub 100 can freely rotate about the main shaft 40 of the generator. Specifically, a circular through hole is formed in the middle of the spoke portion 10, the circumferential surface of the circular through hole serves as a bearing mounting surface, and is interference-fitted with the bearing outer race of the spindle bearing 41, and the bearing inner race is interference-fitted with the outer circumferential surface of the spindle 40 to be fixedly mounted.

Further, in order to reduce the weight of the hub 100, the thickness of the spoke portion 10 may be made small relative to the thickness of the spindle bearing mounting portion 11, in which case the spindle bearing mounting portion 11 is formed as an inner flange projecting in the axial direction from the inner circumference of the spoke portion 10. In order to ensure the installation space of the stator, the axial extension length of the inner flange is not too long so as not to interfere with the stator. In addition, as shown in fig. 1-2, a plurality of lightening holes 12 may be formed in the spoke portion 10 in order to further reduce the weight of the hub 100. The lightening hole 12 may also be used as a manhole, a maintenance channel, a heat dissipation channel, or the like.

At least two blade mounting flanges 30 are also formed on the outer circumference of the spoke portion 10 for connection with the blades. The number of blade mounting flanges 30 corresponds to the number of blades to be mounted, and a plurality of blade mounting flanges 30 are evenly arranged along the circumference of the hub 100. In the example shown in the drawings, three blade mounting flanges 30 are formed on the outer circumference of the spoke portion 10. A pitch drive mounting portion 31 may also be formed on the inner side of the impeller mounting flange 30 for mounting a pitch drive. However, the present invention is not limited thereto, and the pitch drive mounting portion may be mounted outside the impeller mounting flange 30 depending on the position of the blade with respect to the blade mounting flange 30. In the case where at least two blade pitch drive drives are provided, the number of pitch drive mounts 31 may also be at least two.

The axial direction of the blade mounting flange 30 substantially coincides with the radial direction of the spoke portion 10, but has a predetermined angle (e.g., about 3-7 degrees) with the radial direction of the spoke portion 10 to ensure that the blade is inclined toward the front of the nacelle after being mounted, thereby avoiding collision of the blade with the tower. Thus, the flange end faces of the blade mounting flanges 30 have a certain inclination with respect to the axial direction of the hub 100.

Fig. 4 shows a schematic cross-sectional view of a generator built into the hub 100.

As shown in fig. 4, the main shaft 40 is mounted on the main shaft bearing mounting portion 11 through the main shaft bearing 41, and the hub 100 is rotated around the main shaft 40. The main shaft bearing 41 may be a double row tapered roller bearing, and a bearing outer race is closely fitted to an inner circumferential surface of the main shaft bearing mounting part 11 to be fixed to each other, and a bearing outer race is closely fitted to an outer circumferential surface of the main shaft 40 to be fixed to each other. The generator 50 may be mounted on the rear side of the hub 100. Rotor 51 of generator 50 is fixed to an outer rotor mounting case formed by hub 100, and is fixed to hub 100 so as to be rotatable together with hub 100. The stator 52 is supported by the main shaft 40. For example, a stator mounting flange 42 is formed on the main shaft 40, a stator bracket is mounted on the stator mounting flange 42, and a stator 52 is mounted on the stator bracket, is located radially inward of the rotor 51, and forms an air gap between the rotor 51 and the stator 52 in the radial direction. The rotor 51 rotates with the hub 100 to rotate around the stator 52, and conversion of wind energy into electric energy is achieved.

Compared with the structure of the direct-drive wind generating set in the prior art, the wind generating set adopting the hub provided by the embodiment of the invention has the advantages that the generator is arranged in the hub 100, and the length of the main shaft is greatly shortened, so that the transmission distance from the hub to the main shaft of the generator is greatly shortened, the kinetic energy transmission efficiency is improved, the steel consumption is reduced, the cost is saved, and the volume of the generator is reduced.

In addition, because the length of the main shaft is shortened, the generator and the hub can be stably supported by adopting a single main shaft bearing. And the distance between the generator and the main shaft bearing is shorter, and the mass center of the generator and the hub is closer to the main shaft bearing, so that the bending moment born by the main shaft bearing is reduced, and the service life of the main shaft bearing is prolonged.

In the embodiment of the invention, the main shaft and the generator base can be of a separate structure or can be of an integral structure. In the case of a main shaft manufactured separately from the generator base, the fixed connection of the main shaft to the generator base can be realized by means of a connecting flange.

Although fig. 4 shows a schematic view of one generator being installed in the hub, the present invention is not limited thereto, and a plurality of generators may be installed in parallel in the generator case formed by the hub 100. Fig. 5 shows a cross-sectional view of two generators arranged in the hub.

As shown in fig. 5, the outer flange 20 extends forward and backward in the axial direction from the outer circumference of the spoke portion 10, so that one generator housing chamber is formed at the rear side and the front side of the spoke portion 10, respectively, thereby forming a first rotor mounting case at the rear side and a second rotor mounting case at the front side by the hub 100. A first generator 70 is mounted on the rear side of the spoke portion 10, and a rotor 71 of the first generator 70 is mounted on a first rotor mounting case. The second generator 80 is mounted on the front side of the spoke portion 10, and the rotor 81 of the second generator 80 is mounted on the second rotor mounting case. The hub 100 is fitted to the outer race of the spindle bearing 41 through the spindle bearing mounting portion 11, and the spindle 40 is fitted to the inner race of the spindle bearing 41 through the spindle bearing 41. The stator of the first generator 70 is mounted on the main shaft 40 through a stator bracket and is located at the rear side of the spoke portion 10. The stator 82 of the second generator 80 is mounted on the main shaft 40 through a stator bracket and is located at the front side of the spoke portion 10. As the hub 100 rotates about the main shaft 40, the rotor 71 of the first generator 70 and the rotor 81 of the second generator 80 rotate about their

stators

72 and 82, respectively, thereby effecting conversion of wind energy into electrical energy. In the example shown in the drawings, the first generator 70 and the second generator 80 are provided in parallel on the main shaft 40, but the internal circuits of the first generator 70 and the second generator 80 may be connected in parallel with each other or in series with each other.

Although an example in which two generators are installed is shown in fig. 5, the number of generators is not limited to two, and may be three or more. Further, the mounting positions of the plurality of generators are not limited to being mounted on the front and rear sides of the spoke portion 10, respectively, but may be mounted on the same side of the spoke portion 10.

In the case of incorporating a plurality of generators in the hub, the structure of the generator is made more compact. Meanwhile, the distance between the center of mass of the generator and the hub relative to the main shaft bearing is greatly shortened, and the bending moment applied to the main shaft bearing is reduced.

Fig. 6 shows a schematic cross-sectional view of a generator base formed as a unitary structure with a main shaft. Fig. 7 illustrates a perspective view of the hub 100 and the main frame 200 of the internal generator mounted together according to an exemplary embodiment of the present invention. Fig. 8 shows a cross-sectional view of a nacelle part of a wind park according to an embodiment of the invention, wherein a hub is applied. Fig. 9 shows a perspective view of a nacelle part of a wind park according to an embodiment of the invention.

As shown in fig. 6-9, the lower end of the main frame 200 is fixedly connected to the tower via a tower connection flange, thereby forming a support structure for supporting the generator. The main chassis 200 further includes a main shaft part 240 formed at a front end of the main chassis 200. Main shaft portion 240 integrally extends from the main frame 200 body portion toward hub 100 by a predetermined length to form a main shaft for supporting the generator. The main shaft portion 240 is mounted to the main shaft bearing mounting portion 11 of the hub 100 through the main shaft bearing 40, so that the main shaft portion 240 and the hub 100 are fitted to each other such that the hub 100 can rotate about the main shaft portion 240.

The front side of the hub 100 according to an embodiment of the present invention may be provided with a nacelle connecting part so that the nacelle 300 is mounted on the front side of the hub 100. The rear side of the hub 100 may also be provided with a nacelle cover connection to thereby connect with the nacelle cover 400. As an example, the outer diameter of the pod 300 is smaller than the outer diameter of the outer flange 20, and the pod 300 is mounted on and covers the front surface of the hub 100, not the outer circumferential surface of the hub 100. The nacelle cover 400 is mounted on and covers the rear surface of the hub 100. As an example, the outer diameter of the connection portion of the nacelle cover 400 with the hub 100 is smaller than the outer diameter of the outer flange 20, and therefore, the nacelle cover 400 does not cover the outer circumferential surface of the hub 100 either. According to the embodiment of the invention, the hub 100 is exposed, and the design mechanism for spacing the hub 100 between the air guide sleeve 300 and the nacelle cover 400 effectively reduces the size and the design and processing difficulty of the air guide sleeve 300 or the hub 100.

According to the embodiment of the invention, as the generator accommodating cavity is arranged in the hub 100 and the outer rotor shell for installing the outer rotor of the generator is formed by the hub 100, the generator can be internally arranged in the hub 100, and compared with the prior art, the structure and the installation process are simplified, and the structure is more compact. In addition, the steel consumption is saved, and the transportation cost is reduced. Therefore, according to the embodiment of the invention, the hub and the generator are designed into a whole, and the generator is arranged in the hub, so that the reliability and the economy of the product can be improved.

According to an embodiment of the invention, the nacelle base is formed as a one-piece structure with the main shaft. Namely, the front end of the main frame plays a role of the main shaft, so that the connecting structure and the connecting process of the main shaft and the cabin base in the prior art are reduced, the transmission connection is shortened, and the transmission efficiency is improved. The distance between the hub and the cabin base serving as a supporting point is reduced, so that the stability of the wind generating set is further improved.

In addition, because the generator is arranged in the hub, compared with a conventional wind generating set, the diameter of the outer circumference of the hub is increased, and the mounting positions of the blade mounting flanges on the hub extend outwards, so that the wind sweeping area of the impeller can be effectively increased and the generating capacity can be improved under the condition of mounting the blades with the same length. Furthermore, the blade mounting flange may protrude outwardly with respect to the outer flange of the hub. To further increase the swept area, the blade mounting flange 30 may protrude outward a predetermined length with respect to the outer flange 20 in the radial direction of the spoke portion 10, so that the mounting position of the blade mounting flange on the hub extends further outward.

Although the present invention has been described with reference to preferred embodiments, the above description of the embodiments is only for the purpose of helping to understand the principle and spirit of the present invention. It should be noted that various modifications could be made to the invention by those skilled in the art without departing from the principle of the invention, and these modifications would fall within the scope of the claims of the invention.

Claims

1. A direct drive wind turbine generator system, comprising: a hub (100), a plurality of generators (70, 80), a main shaft (40) and a main shaft bearing (41),

the hub (100) is rotatably mounted on the main shaft (40) by the main shaft bearing (41), the hub (100) forms a generator outer housing for the plurality of generators (70, 80), and the plurality of generators (70, 80) are mounted in parallel within the generator outer housing.

2. The direct drive wind power plant according to claim 1, wherein the hub (100) comprises a disk-shaped spoke portion (10) and an outer flange (20), the outer flange (20) extending a predetermined length in an axial direction from an outer circumference of the spoke portion (10) to form the generator outer housing.

3. The direct drive wind turbine generator set according to claim 2, wherein a main shaft bearing mounting portion (11) is formed at a middle portion of the spoke portion (10), a bearing outer race of the main shaft bearing (41) is tightly fitted to the main shaft bearing mounting portion (11), a bearing inner race of the main shaft bearing (41) is tightly fitted to the main shaft (40), and stators (71, 81) and rotors (72, 82) of the plurality of generators (70, 80) are located between the outer flange (20) and the main shaft (40).

4. The direct drive wind generator according to claim 2, characterized in that the plurality of generators (70, 80) are located on both sides of the spoke portion (10) or on the same side of the spoke portion (10).

5. The direct drive wind turbine according to any of claims 1 to 4, wherein the hub (100) further comprises at least two blade mounting flanges (30) formed on an outer circumference of the spoke portion (10), the blade mounting flanges (30) protruding outwardly by a predetermined length with respect to the outer flange (20) in a radial direction of the spoke portion (10).

6. The direct-drive wind generating set according to claim 5, wherein at least one blade pitch device mounting part (31) is formed on the inner side or the outer side of the blade mounting flange (30), the flange end surface of the blade mounting flange (30) is inclined to the front of the hub (100) by a preset angle, and at least one lightening hole is formed on the spoke part (10).

7. The direct drive wind turbine generator set according to claim 3, wherein a through hole is formed in the middle of the spoke portion (11), the main shaft bearing mounting portion (11) is an inner flange extending from the through hole in the axial direction, and the axial thickness of the main shaft bearing mounting portion (11) is greater than the axial thickness of the spoke portion (10).

8. The direct drive wind park according to claim 1, wherein the wind park further comprises a spinner (300), the spinner (300) being mounted on the front side of the hub (100), and the diameter of the spinner (300) being smaller than the diameter of the hub (100).

9. The direct drive wind park according to claim 1, wherein the wind park further comprises a nacelle cover mounted on the rear side of the hub (100), the diameter of the part of the nacelle cover (100) connected to the hub (100) being smaller than the diameter of the hub (100).

10. A direct drive wind park according to claim 2, wherein the plurality of generators (70, 80) comprises a first generator (70) and a second generator (80), the first generator (70) being mounted at a rear side of the spoke portion (10) and the second generator (80) being mounted at a front side of the spoke portion (10).