Direct-driven generator and vertical-axis wind turbine generator

Abstract

The utility model discloses a direct-driven generator and a vertical shaft wind turbine generator. The direct-driven generator comprises a stator, a rotor, a first end cover and a second end cover, and the direct-driven generator adopts an inner rotor form. And the first end cover and the second end cover are respectively arranged on two end surfaces of the stator along the axial direction of the direct-driven generator. The first end cover and the second end cover support the two bearings respectively, and the two bearings support the rotating shaft of the rotor to rotate relative to the stator. The first end cover extends along the radial direction of the direct-driven generator to form a first end cover flange, and the second end cover extends along the radial direction of the direct-driven generator to form a second end cover flange. The first end cover flange and the second end cover flange are connected through a supporting piece. The special structure of the generator can simplify the impeller rotating shaft structure of the vertical shaft unit, and the generator bearing also serves as the main bearing of the unit, so that the cost is reduced. And the load except the torque is directly transmitted to the tower through the end cover, so that the stress condition of the generator is optimized.

Description

Technical Field

[0001] The utility model belongs to the technical field of wind power generation, and particularly relates to a direct-drive generator and a vertical-axis wind turbine unit. Background Technique

[0002] Wind power is the most valuable power generation method for large-scale development and commercial development prospects in the field of renewable energy. The available wind energy is widely distributed and has huge reserves globally.

[0003] Vertical-axis wind turbine units have always been favored for small wind turbine applications due to their insensitivity to wind direction changes and low noise during impeller rotation. The topological structure of vertical-axis wind turbine units is relatively simple. The blades are fixed on the impeller rotating shaft through connecting rods, and the impeller rotating shaft is directly connected to the rotor of the direct-drive generator. The stator of the direct-drive generator in the vertical-axis wind turbine unit is connected to the top of the tower. Vertical-axis wind turbine units with gearboxes are relatively rare. The first reason is that although the gearbox can increase the generator speed and thus reduce the generator cost, due to the relatively small rated capacity of vertical-axis wind turbine units, the total cost of the gearbox and the generator is not much different from the cost of a low-speed direct-drive generator. The second reason is that as a high-speed rotating machine, the gearbox will bring more operation and maintenance workload and cost to the entire vertical-axis wind turbine unit, and also increases the risk points.

[0004] Most conventional vertical-axis wind turbines are adapted to use existing direct-drive generator products on the market. That is to say, vertical-axis wind turbine manufacturers will adjust the structural form of their turbines according to the existing direct-drive generator products. Since the existing direct-drive generator products on the market are usually not specifically designed for wind power and need to take into account other application fields, the bearings of the direct-drive generator cannot be used as the main bearings of the wind turbine. The main reason is that the bearings of the direct-drive generator cannot meet the load-bearing requirements of the wind turbine. Therefore, the current solution of vertical-axis wind turbine manufacturers is to set up independent main bearings on the impeller of the vertical axis. That is to say, including the bearings of the generator, the entire turbine contains three to four bearings. At the same time, due to the special structure of the impeller of the vertical axis, the blades need to be fixed to the impeller rotating shaft of the vertical axis through connecting rods. Therefore, the impeller rotating shaft of the vertical axis must be relatively fixed to the outer ring (i.e., the moving ring) of the main bearing and rotate together relative to the inner ring (i.e., the fixed ring). Then, a fixed shaft must be set inside the impeller rotating shaft, which is very similar to the structure of a conventional horizontal-axis direct-drive wind turbine. Further, since the impeller rotating shaft of the vertical axis is outside the fixed shaft and the impeller rotating shaft of the vertical axis needs to be connected to the rotor of the direct-drive generator, the direct-drive generator must adopt an outer-rotor structure form. This configuration of a fixed shaft, a rotating shaft, an independent main bearing, and an outer-rotor generator is relatively complex in structure and high in cost. Apparently, vertical-axis wind turbine manufacturers choose existing direct-drive generator products, which can reduce the cost of the generator. In fact, because of these existing direct-drive generator products, the structure of the turbine is forced to be more complex, thus increasing the cost of the entire turbine. Therefore, a new turbine solution or generator solution needs to be proposed to replace this configuration of a fixed shaft, a rotating shaft, an independent main bearing, and an outer-rotor generator, so as to achieve the technical effects of simplifying the turbine structure, optimizing the load-bearing, and reducing the cost. Summary of the Invention

[0005] In order to solve at least one of the above technical problems, in a first aspect, a direct-drive generator is provided, which includes a stator, a rotor, a first end cover, and a second end cover; the direct-drive generator adopts an inner-rotor form; the first end cover and the second end cover are respectively arranged at two end faces of the stator along the axial direction of the direct-drive generator; the first end cover and the second end cover are respectively provided with two bearings; the two bearings support the rotating shaft of the rotor to rotate relative to the stator; the first end cover extends radially along the direct-drive generator to form a first end-cover flange, and the second end cover extends radially along the direct-drive generator to form a second end-cover flange; the first end-cover flange and the second end-cover flange are connected by a support member; the support member is located outside the outer surface of the base of the stator.

[0006] In a further technical solution, the first end-cover flange is arranged at intervals or continuously in the circumferential direction of the first end cover, and the second end-cover flange is arranged at intervals or continuously in the circumferential direction of the second end cover.

[0007] Flanges are provided at two end faces of the base of the stator along the axial direction of the direct-drive generator, and are respectively connected to the first end cover and the second end cover.

[0008] Heat dissipation ribs are provided on the outer surface of the base of the stator, and the heat dissipation ribs are arranged perpendicular or parallel to the axial direction of the direct-drive generator, or partially perpendicular to the axial direction of the direct-drive generator and partially parallel to the axial direction of the direct-drive generator.

[0009] Both the first end cover and the second end cover are conical end covers.

[0010] In a second aspect, a vertical-axis wind turbine is provided, which includes a direct-drive generator, a vertical-axis impeller and a tower described in the first aspect; the top of the tower is connected to the second end cover of the direct-drive generator, and the rotating shaft of the vertical-axis impeller is connected to the rotor of the direct-drive generator; the blades in the vertical-axis impeller are connected to the rotating shaft of the vertical-axis impeller through blade connecting rods.

[0011] In a further technical solution, the rotating shaft of the vertical-axis impeller adopts a hollow tubular structure or a lattice structure.

[0012] A brake disc is provided between the rotating shaft of the vertical-axis impeller and the rotating shaft of the rotor of the direct-drive generator, and the brake disc rotates coaxially with the vertical-axis impeller and the rotor of the direct-drive generator.

[0013] A braking device is provided on the end face of the first end cover of the direct-drive generator close to the vertical-axis impeller.

[0014] The top of the tower is connected to the second end cover through the flange of the second end cover, or directly connected to the end face of the second end cover.

[0015] The beneficial effects of the present utility model are as follows: The direct-drive generator proposed in this solution adopts an inner-rotor form, and two end covers respectively support two bearings, and the two bearings support the rotation of the rotor rotating shaft. The impeller rotating shaft can be directly connected to the generator rotor, without the need to set additional main bearings and fixed shafts, which not only simplifies the structure but also reduces the cost of the impeller. The two bearings of the generator are also the main bearings of the entire wind turbine, and the axial force and radial force from the impeller are directly transmitted to the tower along the end cover, and the generator can be rotated by a pure torque load to generate electric energy, and the stress condition of the entire load-bearing structure is optimized. Description of the Drawings

[0016] Figure 1 Schematic diagram of a direct-drive generator according to an embodiment of the present utility model;

[0017] Figure 2 Axonometric view of a direct-drive generator according to an embodiment of the present utility model;

[0018] Figure 3 Schematic diagram of an end cover of a direct - drive generator according to an embodiment of the present utility model;

[0019] Figure 4 Schematic diagram of a flange of an end cover of a direct - drive generator according to an embodiment of the present utility model;

[0020] Figure 5 Schematic diagram of a support member for connecting an end cover of a direct - drive generator according to an embodiment of the present utility model;

[0021] Figure 6 Schematic diagram of a vertical - axis wind turbine according to an embodiment of the present utility model;

[0022] Figure 7 Schematic diagram of a rotating shaft of an impeller of a vertical - axis wind turbine according to an embodiment of the present utility model;

[0023] Figure 8 Schematic diagram of a partial connection between an impeller and a generator of a vertical - axis wind turbine according to an embodiment of the present utility model;

[0024] Figure 9 Schematic diagram of a vertical - axis wind turbine with a lattice tower according to an embodiment of the present utility model;

[0025] Figure 10 Schematic diagram of a vertical - axis wind turbine with a cylindrical tower according to an embodiment of the present utility model.

[0026] Explanation of the reference numerals in the drawings:

[0027] 1. Stator, 1.1. Stator end flange, 1.2. Heat dissipation ribs, 2. Rotor, 2.1. Rotor rotating shaft, 3. First end cover, 3.1. First end - cover flange, 4. Second end cover, 4.1. Second end - cover flange, 5. Bearing, 6. Support member, 7. Direct - drive generator, 8. Vertical - axis impeller, 8.1. Impeller rotating shaft, 8.2. Blade connecting rod, 8.3. Blade, 9. Lattice tower, 9.1. Main chord, 10. Cylindrical tower.

[0028] It should be noted that the above - mentioned drawings are used to illustrate the features of the present utility model, and are not intended to show any actual structure or reflect details such as the dimensions and relative proportions of various components. For a clearer display of the principle of the present utility model and to avoid obscuring the principle of the present utility model with unnecessary details, the examples in each figure have been simplified. These drawings will not cause inconvenience to those skilled in the relevant art in understanding this patent, while the actual embodiments may include more modules or components. Detailed implementation manners

[0029] For the purpose of making the objectives and technical solutions of the embodiments of the present utility model clearer, the following will describe the embodiments of the present utility model completely in combination with the relevant drawings of the embodiments of the present utility model. The patents described herein are only a part of the embodiments, not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0030] An embodiment of a direct-drive generator

[0031] As Figure 1 shown, a direct-drive generator includes a stator (1), a rotor (2), a first end cover (3) and a second end cover (4). The two end faces of the stator (1) along the axial direction of the direct-drive generator are respectively connected to the first end cover (3) and the second end cover (4). As Figure 2 shown, the first end cover (3), the second end cover (4) are connected and the end flange (1.1) surfaces of the stator are opposite, and are connected by bolts.

[0032] The direct-drive generator adopts an inner-rotor form, that is, the rotor (2) of the generator is arranged inside the stator (1). As Figure 3 shown, the generator is provided with a total of two bearings (5), and the first end cover (3) and the second end cover (4) respectively support the two bearings (5). Further, the two bearings (5) support the rotation of the rotating shaft (2.1) of the rotor relative to the stator (1). Since the direct-drive generator of this solution is mainly applied to a vertical-axis wind turbine, it can be clearly seen from Figure 3 that one of the bearings (5) has a higher specification (the intuitive feeling is that the radial dimension of the raceway is larger and the roller size is also larger). The reason for this configuration is that the load from the impeller in the vertical-axis wind turbine is transmitted from top to bottom, and the bearing (5) near the upper end needs to bear more load.

[0033] As Figure 4 shown, the first end cover (3) extends radially along the direct-drive generator to form a first end cover flange (3.1), and the second end cover (4) extends radially along the direct-drive generator to form a second end cover flange (4.1). The number of the first end cover flanges (3.1) and the second end cover flanges (4.1) is the same. In this embodiment, in order to cooperate with the tower structure below, the number of the first end cover flanges (3.1) and the second end cover flanges (4.1) is three. Other embodiments can be adjusted according to actual situations. It is particularly worth noting that in some special embodiments, the first end cover flange (3.1) and / or the second end cover flange (4.1) are integrally extended radially by the first end cover (3) and / or the second end cover (4), that is to say, the first end cover flange (3.1) and / or the second end cover flange (4.1) are continuously distributed in the circumferential direction of the first end cover (3) and / or the second end cover (4), rather than like Figure 4be spaced apart like that.

[0034] As Figure 5 shown, the first end - cover flange (3.1) and the second end - cover flange (4.1) are connected by a support member (6). Since the first end - cover flange (3.1) and the second end - cover flange (4.1) are respectively located at the outermost parts of the first end - cover (3) and the second end - cover (4), that is, outside the flange - face bolt holes, the support member (6) is located outside the base of the stator (1). In this embodiment, the first end - cover flange (3.1) and the second end - cover flange (4.1) can be approximately considered to be arranged at positions corresponding to each other along the axial direction of the direct - drive generator. Therefore, the support member (6) can also be approximately considered to be arranged along the axial direction of the direct - drive generator.

[0035] The novelty and advantages of the above - mentioned technical solution are as follows:

[0036] a) The direct - drive generator adopts an inner - rotor form, which can simplify the structure of the impeller rotating shaft of the wind turbine and greatly reduce the cost of the impeller part.

[0037] b) The bearing (5) of the direct - drive generator is also the main bearing of the entire wind turbine, reducing the number of bearings.

[0038] c) The first end - cover (3) and the second end - cover (4) act as bearing seats. The first end - cover (3) and the second end - cover (4) are connected by a support member (6). The load can be directly transmitted through the end - cover to the tower below. The base of the generator stator (1) does not need to bear the load from the impeller and only needs to fix the electromagnetic part of the stator (1), optimizing the load - bearing condition of the generator.

[0039] d) The base of the generator, the rotor (2) and the electromagnetic part of the stator (1) can still retain the structure of the original conventional generator. In this solution, only the first end - cover (3), the second end - cover (4), the bearing (5) and the rotor rotating shaft (2.1) need to be added on the basis of the existing motor, reducing the development cost of the new motor.

[0040] As Figure 1 shown, one end of the rotating shaft (2.1) of the rotor close to the first end - cover (3) extends out of the direct - drive generator and is provided with an impeller connection flange for connecting the impeller rotating shaft of the wind turbine.

[0041] The outer surface of the base of the stator (1) is provided with heat dissipation ribs (1.2), and the heat dissipation ribs (1.2) are arranged perpendicular or parallel to the axial direction of the direct drive generator, or a part of the heat dissipation ribs (1.2) are arranged perpendicular or to the axial direction of the direct drive generator, and the remaining heat dissipation ribs (1.2) are arranged parallel to the axial direction of the direct drive generator. In this embodiment, the heat dissipation ribs (1.2) are arranged parallel to the axial direction of the direct drive generator, and this arrangement has the effect of increasing the stiffness of the base and increasing the heat exchange area at the same time. In other embodiments, the heat dissipation ribs (1.2) can also be arranged parallel to the axial direction of the direct drive generator (when the heat dissipation ribs (1.2) are arranged parallel to the axial direction of the direct drive generator, the heat dissipation ribs (1.2) also have the function of "reinforcing ribs" and play a role in increasing the supporting ability), or a combination can be made: there are heat dissipation ribs (1.2) arranged perpendicular to the axial direction of the direct drive generator, and there are also heat dissipation ribs (1.2) arranged parallel to the axial direction of the direct drive generator.

[0042] As Figure 5 shown, both the first end cover (3) and the second end cover (4) are conical end covers. Different from general generators that are only subjected to torque loads. The direct drive generator proposed in this solution is applied to the wind power field, and the rotating shaft of the impeller is directly connected to the rotating shaft (2.1) of the generator rotor. All kinds of loads from the impeller need to be borne by the generator. In addition to enclosing the electromagnetic part of the generator inside the generator, the first end cover (3) and the second end cover (4) also have an important function as bearing seats. The axial and radial loads transmitted by the bearing (5) are continuously transmitted downward through the first end cover (3) and the second end cover (4). Therefore, the shape of the conical end cover is also for axial and radial load bearing, increasing the stiffness of the first end cover (3) and the second end cover (4). If the first end cover (3) and the second end cover (4) both adopt a conventional planar structure, the first end cover (3) and the second end cover (4) may undergo large deformations under the action of radial loads.

[0043] An embodiment of a vertical axis wind turbine

[0044] As Figure 6 shown, it includes a direct drive generator (7), a vertical axis impeller (8) and a tower (9) mentioned in the foregoing content. The top of the tower (9) is connected to the second end cover (4) of the direct drive generator (7), and the rotating shaft (8.1) of the vertical axis impeller is connected to the direct drive generator rotor (2). The blades (8.3) in the vertical axis impeller (8) are connected to the rotating shaft (8.1) of the vertical axis impeller through blade connecting rods (8.2).

[0045] In the configuration of the above vertical-axis wind turbine, the rotor shaft (2.1) of the direct-drive generator cantilever supports the vertical-axis impeller (8). The rotor shaft (2.1) is equivalent to the main shaft of the vertical-axis wind turbine, the bearings (5) of the generator are equivalent to the main bearings of the vertical-axis wind turbine, the first end cover (3) and the second end cover (4) are equivalent to the bearing seats of the vertical-axis wind turbine, and the first end cover (3) or the second end cover (4) is connected to the top of the tower, so that the load from the vertical-axis impeller (8) can be quickly and directly transmitted to the foundation. The whole configuration has a simple structure and clear division of labor, simplifying the complex structure of the impeller shaft of the conventional vertical-axis wind turbine (see the description in the foregoing background art). In fact, the current vertical-axis wind turbines do not adopt the technical solution of this structural configuration of the present application.

[0046] Furthermore, as Figure 7 shown, since the direct-drive generator (7) adopts an inner-rotor structure, the bearings (5) of the direct-drive generator serve as the bearings of the entire vertical-axis wind turbine, making the structure of the shaft (8.1) of the vertical-axis impeller very simple, and a hollow tubular structure or a lattice structure can be directly adopted. In this embodiment, the shaft (8.1) of the vertical-axis impeller is composed of a section of round tube.

[0047] As Figure 8 shown, a brake disc is arranged between the shaft (8.1) of the vertical-axis impeller and the shaft (2.1) of the direct-drive generator rotor, and the shaft (8.1) of the vertical-axis impeller and the shaft (2.1) of the direct-drive generator rotor are respectively connected to the two end faces of the brake disc. The brake disc rotates coaxially with the vertical-axis impeller (8) and the direct-drive generator rotor (2).

[0048] It is particularly worth noting that, combining Figure 6 the overall structure diagram and Figure 8 the partial illustration, it can be seen that the support member (6) between the first end cover (3) and the second end cover (4) of the direct-drive generator and the main chord (9.1) of the lower lattice tower are both made of round tubes. In this embodiment, the support member (6) and the main chord (9.1) of the lattice tower are integrated, that is, the main chord (9.1) extends from the first end cover (3) all the way to the foundation.

[0049] A brake device is arranged on the end face of the first end cover (3) of the direct-drive generator close to the vertical-axis impeller (8). In this embodiment, the brake device adopts a caliper form and can be driven by a motor or a hydraulic device to clamp the brake disc.

[0050] As Figure 9As shown in the figure, when a vertical-axis wind turbine uses a lattice tower (9), it can be considered that the top of the tower (9) is connected to the second end cover (4) through the second end cover flange (4.1). Of course, it can also be regarded as the top of the tower (9) being connected to the first end cover (3) through the first end cover flange (3.1) (in this case, the support member (6) will be regarded as a part of the main chord (9.1) of the lattice tower (9)). As Figure 10 As shown in the figure, when a vertical-axis wind turbine uses a steel cylindrical tower (10), the flange at the top of the cylindrical tower (10) can be directly butt-jointed with the flange of the second end cover (4). In some other embodiments, it can also be regarded as the flange at the top of the cylindrical tower (10) being connected to the first end cover flange (3.1). At this time, the first end cover flange (3.1) should be continuously distributed circumferentially on the first end cover (3), and the support member (6) will be regarded as a part of the cylindrical tower (10), and the stator of the generator is surrounded inside the cylindrical tower (10).

[0051] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "up, down, front, back, left and right" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0052] Unless otherwise clearly defined and limited in the present invention, the terms "installation, connection, and connection" should be understood in a broad sense. For example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, and can also be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0053] Although the present invention has been described with reference to the preferred embodiments, various improvements can be made to it and its components can be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A direct-drive generator, characterized in that, it includes a stator (1), a rotor (2), a first end cover (3) and a second end cover (4); the direct-drive generator adopts an inner-rotor form; the first end cover (3) and the second end cover (4) are respectively arranged on two end faces of the stator (1) along the axial direction of the direct-drive generator; the first end cover (3) and the second end cover (4) are respectively provided with two bearings (5); the two bearings (5) support the rotation of the rotating shaft (2.1) of the rotor relative to the stator (1); the first end cover (3) extends radially along the direct-drive generator to form a first end cover flange (3.1), and the second end cover (4) extends radially along the direct-drive generator to form a second end cover flange (4.1); the first end cover flange (3.1) and the second end cover flange (4.1) are connected by a support member (6); the support member (6) is located outside the outer surface of the base of the stator (1).

2. The direct-drive generator according to claim 1, wherein, The first end cover flange (3.1) is arranged at intervals or continuously in the circumferential direction of the first end cover (3), and the second end cover flange (4.1) is arranged at intervals or continuously in the circumferential direction of the second end cover (4).

3. A direct drive generator according to claim 1, characterized in that, Flanges are arranged on two end faces of the base of the stator (1) along the axial direction of the direct-drive generator, and are respectively connected to the first end cover (3) and the second end cover (4).

4. A direct drive generator according to claim 1, characterized in that, Heat dissipation ribs (1.2) are arranged on the outer surface of the base of the stator (1), and the heat dissipation ribs (1.2) are arranged perpendicular or parallel to the axial direction of the direct-drive generator, or partially perpendicular to the axial direction of the direct-drive generator and partially parallel to the axial direction of the direct-drive generator.

5. A direct drive generator according to claim 1, characterized in that, Both the first end cover (3) and the second end cover (4) are conical end covers.

6. A vertical-axis wind turbine, characterized in that, it includes a direct-drive generator according to any one of claims 1-5, a vertical-axis impeller (8) and a tower (9); the top of the tower (9) is connected to the second end cover (4) of the direct-drive generator (7), and the rotating shaft (8.1) of the vertical-axis impeller is connected to the rotor (2) of the direct-drive generator; the blades (8.3) in the vertical-axis impeller (8) are connected to the rotating shaft (8.1) of the vertical-axis impeller through blade connecting rods (8.2).

7. The vertical axis wind turbine according to claim 6, wherein, The rotating shaft (8.1) of the vertical-axis impeller adopts a hollow tubular structure or a lattice structure.

8. A vertical axis wind turbine according to claim 6, characterized in that, A brake disc is arranged between the rotating shaft (8.1) of the vertical-axis impeller and the rotating shaft (2.1) of the rotor of the direct-drive generator, and the brake disc rotates coaxially with the vertical-axis impeller (8) and the rotor (2) of the direct-drive generator.

9. A vertical axis wind turbine according to claim 6, characterized in that, A brake device is arranged on the end face of the first end cover (3) of the direct-drive generator close to the vertical-axis impeller (8).

10. A vertical axis wind turbine according to claim 6, characterized in that, The top of the tower (9) is connected to the second end cover (4) through the second end cover flange (4.1), or is directly connected to the end face of the second end cover (4).

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