Assembly tools and methods for direct-drive wind turbine generator

Abstract

To provide methods and tools for assembling a hub and a generator for a wind turbine.SOLUTION: The present disclosure relates to methods and tools for assembling a hub and a generator for a wind turbine, and more specifically to methods and tools for assembling a hub, a generator and a main frame for a direct-drive wind turbine. A method comprises providing a wind turbine hub, a generator and a main frame. The method further comprises vertically moving at least one of the hub and generator towards the other of the hub and generator; attaching the hub and the generator to each other to form a hub-generator assembly; turning the hub-generator assembly while gripping the wind turbine hub; and attaching the hub-generator assembly to the main frame.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to methods and tools for assembling a hub and a generator for a wind turbine, and more particularly, to methods and tools for assembling a hub, a generator, and a frame for a direct-drive wind turbine.

Background Art

[0002] Modern wind turbines are commonly used to supply electricity to the power grid. This type of wind turbine generally includes a tower and a rotor disposed on the tower. The rotor, typically including a hub and a plurality of blades, is adapted to rotate under the influence of wind on the blades. The rotation typically generates torque that is transmitted directly ( "direct drive" or "gearless") to the generator via a rotor shaft or via a gearbox. In this way, the generator produces electricity that can be supplied to the power grid.

[0003] In a wind turbine with a gearbox, the gearbox can usually increase the speed of the wind-driven rotor, thus reducing the required size of the generator. In contrast, a direct-drive generator operates at the same rotational speed as the rotor. Thus, these generators generally have a much larger diameter than generators used in wind turbines with gearboxes to supply a similar amount of power as a wind turbine with a gearbox.

[0004] A direct-drive wind turbine generator can have a diameter of, for example, 6 to 10 meters (236 to 328 inches), a length of, for example, 2 to 3 meters (79 to 118 inches), and can rotate at a low speed in the range of, for example, 2 to 20 rpm (revolutions per minute). Alternatively, the generator may also be coupled to a gearbox that increases the rotational speed of the generator to, for example, 50 to 500 rpm or more.

[0005] A generator generally comprises a rotor, a stator, and an air gap separating the rotor and stator, for example, radially. The stator may be an internal structure, and the rotor may surround the stator. The generator may also be a permanent magnet excited generator (PMG).

[0006] Permanent magnets (PMs) are generally mounted on the rotor (although they can also be arranged alternately in the stator structure), while winding elements (e.g., coils) are usually contained within the stator (although they can also be arranged alternately in the rotor structure). An air gap separates the permanent magnets from the coils. Permanent magnet generators are generally considered reliable and require less maintenance than other types of generators. This is a key reason why permanent magnet generators are used in offshore wind turbines, particularly direct-drive offshore wind turbines.

[0007] In direct-drive wind turbines, a frame is generally provided above the tower. The frame typically supports the hub and generator and transmits the load to the tower. The frame, or at least a portion of the frame, may be made of cast steel. The nacelle, a housing located at the top of the wind turbine tower, can cover and protect at least a portion of the frame.

[0008] Once the generator for a direct-drive wind turbine is assembled, that is, the rotor and stator are assembled, the generator must be joined to the wind turbine hub and frame. For example, the generator may be raised and mounted horizontally to the frame. Then, the hub may be mounted to the generator, also horizontally.

[0009] Due to the size and weight of the generator, appropriate tools are required to lift and move it. In particular, the generator must be handled with care so as not to deform the stator and / or rotor, and therefore not to deform the air gap between them.

[0010] To minimize the risk of air gap collapse when handling the generator, the generator may be reinforced. For example, one or more reinforcing members may be attached to the generator to provide additional rigidity before joining it to the frame. Attaching the reinforcing members to the generator, and removing them once the generator is joined to the frame and hub, can be time-consuming. Specific tools may also be required to operate the reinforced generator. [Overview of the Initiative]

[0011] One aspect of the present disclosure provides a method. The method includes the steps of providing a wind turbine hub, a main frame, and a generator. The method further includes the steps of moving at least one of the wind turbine hub and the generator perpendicularly toward the other of the wind turbine hub and the generator; mounting the wind turbine hub and the generator to form a hub-generator assembly; rotating the hub-generator assembly while gripping the wind turbine hub; and mounting the hub-generator assembly to a main frame.

[0012] In this embodiment, the hub and generator are first mounted and then inverted via the hub. The hub-generator assembly can then be joined to the main frame. In this way, the generator is not directly operated, thus protecting the generator's air gap and preventing collapse. By performing the rotation via the hub, the center of gravity of the hub-generator assembly can be placed within the hub, thereby avoiding deformation of the generator.

[0013] Since the hub is the one being reversed, it may become unnecessary to reinforce the generator.

[0014] In a further aspect of the present invention, a tool for operating a hub is provided. The tool comprises a hub operating assembly configured to grip a hub. The tool further comprises two lateral supports for supporting the hub operating assembly between them. The hub operating assembly is configured to displace along the lateral supports and rotate relative to the lateral supports.

[0015] A further embodiment of the present invention provides a method, which includes the steps of: grasping a hub, wherein the portion of the hub configured to be attached to a generator is facing downward; raising the hub; lowering the hub above the generator; raising the hub with the generator attached; and rotating the hub with the generator attached. [Brief explanation of the drawing]

[0016] [Figure 1] This diagram schematically shows a perspective view of an example of a wind turbine. [Figure 2] Figure 1 is a simplified internal cross-sectional view of an example of a wind turbine nacelle and rotor hub. [Figure 3] This is a schematic diagram showing the flowchart of the method. [Figure 4A] This figure schematically shows an example of an implementation of the method shown in Figure 3. [Figure 4B] This figure schematically shows an example of an implementation of the method shown in Figure 3. [Figure 4C] This figure schematically shows an example of an implementation of the method shown in Figure 3. [Figure 4D] This figure schematically shows an example of an implementation of the method shown in Figure 3. [Figure 4E] This figure schematically shows an example of an implementation of the method shown in Figure 3. [Figure 4F] This figure schematically shows an example of an implementation of the method shown in Figure 3. [Figure 4G] This figure schematically shows an example of an implementation of the method shown in Figure 3. [Figure 5]A diagram schematically showing a flowchart of a further method. [Figure 6] A diagram schematically showing a perspective view of an example of a tool for operating a wind turbine hub. [Figure 7] A diagram schematically showing a perspective view of an example of a side support for the tool of FIG. 6. [Figure 8] A diagram schematically showing a perspective view of an example of a hub operation assembly of the tool of FIG. 6. [Figure 9] A diagram schematically showing a top view of the tool of FIG. 6. **DETAILED DESCRIPTION OF THE INVENTION**

[0017] Here, embodiments of the present invention will be referred to in detail, with one or more examples shown in the drawings. Each example is presented as an illustration of the present invention, not as a limitation thereof. In fact, it will be apparent to those skilled in the art that various modifications and changes can be made to the present invention without departing from the scope or spirit thereof. For example, features illustrated or described as part of one embodiment can also be used in conjunction with another embodiment to yield a further embodiment. Accordingly, the present invention is intended to encompass such modifications and changes that fall within the scope of the appended claims and their equivalents.

[0018] FIG. 1 shows a perspective view of an example of a wind turbine 160. In this example, the wind turbine 160 is a horizontal-axis wind turbine. As shown, the wind turbine 160 includes a tower 170 extending from a support surface 150, a nacelle 161 mounted on the tower 170, and a rotor 115 coupled to the nacelle 161. The rotor 115 includes a rotatable rotor hub 110 and at least one rotor blade 120 coupled to the rotor hub 110 and extending outwardly from the rotor hub 110. For example, in the illustrated example, the rotor 115 includes three rotor blades 120. However, in alternative embodiments, the rotor 115 may include more or fewer than three rotor blades 120. Each rotor blade 120 may be spaced from the rotor hub 110 to facilitate rotation of the rotor 115 such that kinetic energy can be converted from the wind into usable mechanical energy and subsequently into electrical energy. For example, the rotor hub 110 may be rotatably coupled to a generator 3 (FIG. 2) to enable the production of electrical energy.

[0019] The tower 170 may be manufactured from tubular steel to define a cavity (not shown in FIG. 1) between the support surface 150 and the nacelle 161. In alternative embodiments, the tower 170 may be any suitable type of tower having any suitable height. According to an alternative form, the tower may be a hybrid tower comprising a concrete portion and a tubular steel portion. Also, the tower may be a partial or complete lattice tower.

[0020] In the example, the rotor blade 120 may have a length in the range of about 15 meters (m) to about 90 meters, 120 meters or more. The rotor blade 120 may have any suitable length that allows the wind turbine 160 to function as described herein. For example, non-limiting examples of blade length include lengths of 20 meters or less, or lengths greater than 37 meters, 48.7 meters, 50.2 meters, 52.2 meters, or 91 meters. When wind strikes the rotor blade 120 from the wind direction, the rotor 115 rotates about the rotor axis. As the rotor blade 120 rotates and is subjected to centrifugal force, the rotor blade 120 is also subjected to various forces and moments. Thus, the rotor blade 120 can be deflected and / or rotated from a neutral or non-deflected position to a deflected position.

[0021] Furthermore, the pitch angle of the rotor blades 120, i.e., the angle that determines the orientation of the rotor blades 120 relative to the wind direction, can be changed by the pitch system, and the load and power generated by the wind turbine 160 can be controlled by adjusting the angular position of at least one rotor blade 120 relative to the wind vector. During the operation of the wind turbine 160, the pitch system can specifically change the pitch angle of the rotor blades 120 so that the angle of attack of (part of) the rotor blades is reduced, thereby facilitating a reduction in rotational speed and / or facilitating a stall of the rotor 115.

[0022] The blade pitch of each rotor blade 120 may be controlled individually by the wind turbine controller 180 or a pitch control system. Alternatively, the blade pitch of all rotor blades 120 may be controlled simultaneously by the control system.

[0023] Furthermore, as the wind direction changes, the yaw direction of the nacelle 161 can be rotated around the yaw axis, thereby positioning the rotor blades 120 relative to the wind direction.

[0024] The wind turbine controller 180 may be located in the center of the nacelle 161. However, in other examples, the wind turbine controller 180 may be located within any other component of the wind turbine 160, or outside the wind turbine. Furthermore, the controller 180 may be communicatively coupled to any number of components of the wind turbine 160 to control the operation of such components.

[0025] The wind turbine controller 180 may include one or more processors and associated memory devices configured to perform various computer implementation functions (e.g., performing methods, steps, calculations, etc. disclosed herein, and storing associated data disclosed herein). The wind turbine controller can perform a variety of different functions, such as receiving, transmitting, and / or executing wind turbine control signals, and controlling the overall operation of the wind turbine. The wind turbine controller may be programmed to control the overall operation based on information received from sensors indicating, for example, load, wind speed, wind direction, turbulence disturbances of components, etc.

[0026] As used herein, the term “processor” refers not only to integrated circuits as they are called in the art as being included in a computer, but also to controllers, microcontrollers, microcomputers, programmable logic controllers (PLCs), application-specific integrated circuits, and other programmable circuits. A processor is also configured to compute advanced control algorithms and communicate with various Ethernet or serial-based protocols (such as Modbus, OPC, and CAN). Furthermore, memory devices may include, but are not limited to, computer-readable media (e.g., random-access memory (RAM)), computer-readable non-volatile media (e.g., flash memory), floppy disks, compact disk read-only memory (CD-ROM), magneto-optical disks (MODs), digital multi-purpose disks (DVDs), and / or other suitable memory elements. Such memory devices may be configured to store suitable computer-readable instructions that, when implemented by a processor, constitute a controller performing the various functions described herein.

[0027] The wind turbine 160 in Figure 1 may be installed at sea or on land. The wind turbine in Figure 1 may also be a direct-drive wind turbine.

[0028] Figure 2 shows a simplified internal cross-sectional view of the nacelle 161 and rotor hub 110 of a direct-drive wind turbine 160, such as that in Figure 1. Some elements of the wind turbine 160 are not shown for clarity. As shown, a generator 3 may be coupled to the rotor hub 110 of the wind turbine 160 to generate electricity from the rotational energy produced. Thus, the rotation of the rotor hub 110 drives the generator 3.

[0029] It should be understood that the frame 1 and generator 3 can generally be supported by a support frame or bed plate 17 positioned at the top of the wind turbine tower 170. The bed plate 17 may be at the bottom or bonded to the bottom flange of the frame 1. The nacelle 161 is rotatably coupled to the tower 170. The bed plate 17 may also be rotatably coupled to the wind turbine tower 170.

[0030] The direct-drive wind turbine 160 in Figure 2 includes a generator 3 mounted on a frame 1. The generator 3 comprises a generator stator 32 and a generator rotor 31 configured to rotate around a rotation axis RA. The frame 1 has a rear section 16 and a front section or a protruding section 11. The protruding section 11 may be formed integrally with the rear section 16 or it may be a separate part. If it is formed separately, fasteners 4 such as bolts can be used to attach the front section 11 and the rear section 16 of the frame 1. The protruding section 11 extends beyond the generator 3. The rear section 16 is provided between the front section 11 and the tower 170.

[0031] The rear portion 16 of frame 1 may be referred to as the main frame 16. The main frame can transmit the loads and vibrations acting on the rotor 115 of the wind turbine 160 to the tower 170 of the wind turbine 160. The main frame may be made of cast steel. The main frame may have a bottom opening, a front opening, and a rear opening. The bottom opening can allow passage between the main frame and the inside of the tower 170, the front opening can allow passage between the main frame and the inside 111 of the rotor hub 110, for example, through the front 11, and the rear opening can allow passage between the main frame and the inside of the nacelle 161.

[0032] In Figure 2, the projection 11 extends along the rotation axis RA toward the rotor hub 110 of the wind turbine 160. Therefore, the projection 11 may extend in the windward direction along the rotation axis RA. At least a portion of the projection 11 may be installed in a space 111 defined inside the rotor hub 110. The space 111 may be defined as a hollow body of the rotor hub 110.

[0033] The protruding portion 11 of frame 1 may be referred to as the main frame 11. The main frame 11 may comprise a first structure and a second structure. The first and second structures are configured to rotate relative to each other about a rotation axis RA. The first structure may be mounted on the generator stator 32, and the second structure may be mounted on the generator rotor 31. The terms first and second are interchangeable herein.

[0034] In Figure 2, the first structure is the inner structure 13, and the second structure is the outer structure 12. In another example, the first structure may be the outer structure, and the second structure may be the inner structure. In both examples, the inner and outer structures can rotate relative to each other about the axis of rotation RA.

[0035] The outer structure 12 may be operably connected to the rotor hub 110 via the generator rotor 31. The latter can be achieved, for example, by a series of bolts 4. The bolts 4 may join the rotor hub 110, the outer structure 12, and the generator rotor 31 to each other such that at least a portion of the generator rotor 31 is sandwiched between the rotor hub 110 and the outer structure 12. This exemplary joining allows the rotational motion of the rotor hub 110 to be transmitted to the outer structure 12 via the generator rotor 31. Conversely, if the outer structure 12 is braked, for example, the generator rotor 31 and the rotor hub 110 can also be braked. In another example, the joining may be achieved by any fasteners available on the market or by welding.

[0036] The first structure, for example, the inner structure 13, may have a tapered region 18 toward the rotor hub 110. The second structure, for example, the outer structure 12, may be rotatably mounted on the tapered region 18. That is, the second structure may rotate about the rotation axis RA and the first structure. The tapered region 18 may, at least partially, protrude from the generator 3 toward the rotor hub 110.

[0037] The direct-drive wind turbine 160 may further include a pair of bearings 15 between a second structure, such as an outer structure 12, and a first structure, such as an inner structure 13. The pair of bearings 15 may be spaced apart from each other along the rotation axis RA. Alternatively, a single bearing may rotatably connect the first structure and the second structure.

[0038] In Figure 2, the generator rotor 31 rotatably surrounds the generator stator 32. However, in other examples, the generator stator may surround the generator rotor.

[0039] One aspect of this disclosure provides Method 200. A schematic diagram of Method 200 is provided in Figure 3. Examples of possible implementations of Method 200 are shown in Figures 4A to 4G. Method 200 can be implemented by using a tool configured to perform the steps of Method 200. Examples of such a tool 400 can be seen, for example, in Figures 4A to 4G and Figure 6.

[0040] The method includes the step of providing a wind turbine hub 110, a generator 3, and a main frame 16 in block 210. The method includes the step of moving at least one of the hub 110 and the generator 3 perpendicularly toward the other in block 220. The hub 110 and the generator 3 are brought closer together so that a portion of the hub configured to be attached to the generator faces a portion of the generator configured to be attached to the hub. Any generator suitable for a direct-drive wind turbine may be used. For example, an electric-excited generator may be used. In other examples, a permanent magnet-excited generator may be used. In some examples, the generator may be a superconducting generator.

[0041] In some examples, the hub 110 may descend toward the generator 3. This is schematically represented in Figure 4C. In Figure 4C, the tool 400 holds the hub 110 such that a portion of the hub configured to connect to the generator faces downward. The generator 3 is positioned below the hub 110, so that the hub and generator can be mounted as the hub descends toward the generator. The generator may be mounted on a generator support 35. In this example, the generator 3 remains stationary and does not move toward the hub 110.

[0042] The tool 400 may include one or more sensors 443 (see, for example, Figure 8) configured to detect the generator 3. For example, a laser and / or camera may be provided on the tool, for example, on the tool's hub operating assembly 430, so that the position of the hub 110 relative to the generator can be determined. A sensor suitable for measuring the distance between the hub 110 and the generator 3 may be used. One or more sensors, targets, and / or marks may be provided on the generator 3 for use with one or more sensors 443 in the tool 400.

[0043] In some other examples, the generator 3 may move vertically toward the hub 110, for example, by a platform that is movable vertically, for example, upward. The generator 3 may move in addition to, or instead of, moving the hub 110. Because the generator is inherently less rigid than the hub, operation of the generator can cause deformation. In Figures 4C and 4D, the hub remains stationary. This helps to avoid deformation of the air gap between the stator and rotor.

[0044] In some examples, the generator 3 may be provided pre-mounted, for example, attached to the front frame 11. The front frame 11 is configured to be attached to the main frame 16. For example, in Figure 4C, the generator 3 is attached to the front frame 11. The attachment of the generator 3 and the front frame 11 may be performed before installing the generator 3 in a position suitable for joining the generator 3 to the hub 110, for example substantially below the hub 110. The front frame 11 may include a portion configured to support the generator 3, for example, an inner structure 13, and a portion configured to be attached to the wind turbine hub 110, for example, an outer structure 12.

[0045] The method further includes the step of mounting the hub 110 and the generator 3 in block 230 to form a hub-generator assembly 5. Figure 4D illustrates this step. Fasteners such as bolts 4 may be used. In general, any suitable type of fastener may be used. If the generator is mounted on the front frame 11, the hub 110 may be mounted on a portion configured to be mounted on the wind turbine hub 110, for example, the outer structure 12 in the example of Figure 2.

[0046] By having the generator 3 on the ground or on a support 35 on the ground, the installation of the hub and generator can be facilitated. Furthermore, operation of the generator 3 that could lead to air gap collapse can be avoided.

[0047] The method further includes the step of rotating the hub-generator assembly 5 while gripping the hub 110 in block 240. Figure 4F shows an example of this. In Figure 4F, the tool 400 grips the hub 110 and rotates the hub-generator assembly 5 around the rotation axis 460 (see also, for example, Figures 6 and 9). That is, the hub-generator assembly is inverted from a substantially vertical orientation to a substantially horizontal orientation.

[0048] As the rotating shaft 460 crosses the hub 110, the force and load are concentrated on the hub. The rotating shaft 460 may be located near the center of gravity of the hub-generator assembly 5. Thus, the hub 110 and tool 400 are used as counterweights to reinforce the connection with the generator 3. In contrast to directly manipulating the generator, such as by pivoting it on its outer surface, the air gap of the generator 3 can be protected from collapse or deformation. Furthermore, it may be unnecessary to add reinforcing materials to the generator to avoid deformation.

[0049] Before rotating the hub generator assembly 5, the hub generator assembly may be raised. Raising it allows for sufficient space to rotate the hub generator assembly 5 without damaging it. Raising it also allows for positioning the hub generator assembly 5 at a suitable height (distance from the floor) for joining to the main frame 16. If a support structure 35 is used to support the generator 3 (or the generator 3 and the front frame 11), the structure 35 may be removed before rotating the hub 110. The hub generator assembly 5 is raised in Figure 4E before it rotates in Figure 4F.

[0050] The hub generator assembly may be rotated by 70° to 110°, specifically 80° to 100°. For example, the hub generator assembly may be rotated by approximately 85°, 90°, or 95°. Such rotations facilitate the orientation of the hub generator assembly 5 for coupling to the main frame 16. The hub operating assembly 430 of the tool 400, for example, may be reinforced 445 in the portion below the hub generator assembly 5 after rotation.

[0051] The method further includes the step of mounting the hub generator assembly 5 to the main frame 16 in block 250. The main frame 16 can move toward the hub generator assembly 5, for example, substantially horizontally. If the generator 3 is supplied without being mounted to the front frame 11, the main frame 16 may be mounted to the front frame 11 before mounting the hub generator assembly to the main frame 16. Mounting the hub generator assembly 5 to the main frame 16 may also be done by the front frame 11. If the main frame 16 and the front frame 11 are supplied as a single unit, movement of the main frame 16 includes movement of the front frame 11; that is, frame 1 moves. A portion of frame 1 configured to be mounted to the hub generator assembly 5, for example a portion of the front frame 11, may be positioned to face a portion of frame 1, for example a portion of frame 11, which is configured to be mounted to the hub generator assembly 5. Sensors may be installed on the hub generator assembly 5 and / or frame 1 to assist in alignment. Targets or marks may be installed additionally or alternatively on either the hub generator assembly or the frame.

[0052] If the hub generator assembly 5 includes the front portion 11 of the frame 1, the hub generator assembly 5 may be mounted in particular to the main frame 16. For example, the front frame 11, and optionally the internal structure 13 (see Figure 2), may be mounted to the main frame 16. Any suitable fasteners, including bolts 4, may be used. For example, nuts and bolts may be used to join the rear flange of the internal structure 13 to the front flange of the main frame 16.

[0053] As shown in Figure 4G, the main frame 16 may be incorporated into the nacelle 161, and the nacelle 161 having the main frame 16 may move toward the hub generator assembly 5. The movable platform 36 can move the nacelle 161 horizontally.

[0054] By performing Method 200, the hub 110, generator 3, and main frame of the direct-drive wind turbine 160 can be mounted without damaging the generator's air gap. The risk of damaging the generator's air gap can be reduced by first joining the hub and generator, and then inverting the assembly while gripping the hub. Since the generator does not rotate directly (i.e., the generator rotates, but through the hub), it may not be necessary to add reinforcement to the generator. Mounting the parts can be done faster and simpler than first operating the generator to mount it to the frame and then attaching the hub to the generator. Also, joining the hub and generator vertically is easier and safer than joining them horizontally, as it requires fewer tools and structural manipulations above the ground in the first case.

[0055] In relation to Method 200 and further to Figures 4A and 4B, the hub 110 may be gripped before step 210. For example, the tool 400 may grip and raise the hub 110 before moving the hub 110 toward the generator 3, for example, by lowering it. Gripping may involve lowering the hub operating assembly 430 of the tool 400 so that the hub operating assembly 430 surrounds the hub 110. Figure 4A shows the hub 110 positioned below the tool. The hub 110 may be mounted on the hub support 37. The hub is mounted such that a portion of the hub configured to be attached to the generator 3 faces downward. The hub may be mounted such that when the tool is operated to grip the hub, for example by lowering the hub operating assembly 430 of the tool 400, the engagement pin 440 for gripping the hub is positioned between the hub openings for mounting the wind turbine blades 120.

[0056] A sensor 443 on the hub operating assembly 430 of the tool 400 can assist in precisely positioning the tool portion relative to the hub, for example, around the hub. The hub operating assembly 430 may move vertically and horizontally to adjust its position relative to the hub. The lateral support 410 of the tool may assist in moving the hub operating assembly 430 vertically and horizontally.

[0057] Gripping the hub 110 may include clamping the hub 110 at at least two points between the hub openings for mounting the wind turbine blades 120. The hub 110 may be particularly reinforced in these areas so that the hub-generator assembly 5 can be rotated without deforming the hub 110. Clamping the hub in these areas may be particularly suitable for later swiveling the hub-generator assembly 5 and protecting the generator's air gap.

[0058] The hub operating assembly 430 of tool 400 may include a hub engagement pin 440. The pin 440 moves toward the hub and engages with the hub, for example, the hub surface between openings, to position the wind turbine blades 120 as shown in Figure 4B. The engagement pin 440 may be configured to mate with a receptacle on the hub. A male-female coupling may be formed.

[0059] Further aspects of this disclosure provide a method 300 schematically shown in Figure 5. This method can be performed by a tool 400, as will be further described below with respect to Figures 6-9, for example.

[0060] The method includes a step of gripping the hub 110 in block 310, with the hub portion configured to be attached to the generator 3 facing downward. The hub operating assembly 430 of tool 400 may be lowered. The hub operating assembly 430 of tool 400 may surround the hub 110. The hub 110 may be clamped between the hub openings for attaching the wind turbine blades. The hub engagement pin 440 may move toward the hub 110 for this purpose. These embodiments can be seen in Figures 4A and 4B.

[0061] The method further includes the step of raising the hub in block 320. The generator 3 may be positioned substantially below the hub 110, either independently or mounted on the front frame 11.

[0062] The method further includes, in blocks 330 and 340, the steps of lowering the hub above the generator and attaching the generator 3 to the hub 110 (see Figures 4C and 4D). The step of lowering the hub may include the step of measuring the distance between a tool, such as the hub operating assembly 430, and the hub.

[0063] This method further includes the step of raising the hub 110 with the generator 3 attached in block 350. The tools for raising the hub and generator can be seen in Figure 4E.

[0064] This method further includes the step of rotating the hub in block 360 with the generator attached. The rotation may be 80° to 100°. After rotation, the main frame 16 and generator 3 may be attached. A tool for rotating the hub-generator assembly can be seen in Figure 3F. If the generator is supplied mounted on the front frame 11, the hub-generator assembly may be attached to the main frame 16 via the front frame 11.

[0065] Aspects of Method 200 can be combined with aspects of Method 300. The explanations provided for Method 200 also apply to Method 300, and vice versa.

[0066] Further aspects of the present disclosure provide a tool for operating a hub. The tool comprises two lateral supports and a hub operating assembly. The lateral supports are configured to support the hub operating assembly between them. The hub operating assembly is configured to grip a hub. The hub operating assembly is also configured to move along the lateral supports and rotate relative to the lateral supports. The methods 200 and 300 described above can be performed using this tool.

[0067] Figure 6 shows a perspective view of an example of tool 400. Tool 400 comprises two lateral supports 410 and a hub operating assembly 430. The hub operating assembly 430 may rotate about a pivot axis 460. The hub operating assembly 430 may comprise a base 431 and two arms 435 mounted on either side of the base 431. The arms 435 are movably connected to the lateral supports 410. The direction along the length of the arms 435 defines the pivot axis 460. When parallel to the ground, the pivot axis 460 defines the Y-axis.

[0068] The hub operating assembly 430 may move parallel to the ground along the Y and X axes (see Figure 6). The hub operating assembly 430 may also move perpendicularly along the Z axis, i.e., perpendicular to the ground. The X, Y, and Z axes are perpendicular to each other. The hub operating assembly 430 may also rotate about any of the X, Y, and Z axes. The lateral support 410 may, if necessary, allow movement of the hub operating assembly in all of these directions. The lateral support 410 may also allow rotation of the hub operating assembly about the rotation axis 460.

[0069] Figure 7 shows a perspective view of an example of a lateral support 410. The lateral support 410 may include a hub operating assembly engaging element 411. The element 411 is configured to engage with and rotate the hub operating assembly 430, for example, the arm 435 of the hub operating assembly 430. An actuator, such as a motor, may be incorporated into the lateral support 401 and connected to the hub operating assembly engaging element 411, causing the rotating element 411, and therefore the hub operating assembly 430, to rotate about a rotation axis 460, for example, about the Y-axis. The element 411 may be a shaft, or may include a shaft.

[0070] The hub operating assembly engaging element 411 may move up and down along the Z-axis. The lateral support 410 may include a vertical guide system 415 for this purpose. The vertical guide system 415 can vertically guide the element 411, which is configured to engage with and rotate the hub operating assembly 430. The vertical guide system may include two vertical guides 416 along which the hub operating assembly engaging element 411 can be vertically displaced. The vertical guides 416 may be screws, such as worm screws. The vertical guides 416 may be separated along the X-direction.

[0071] The hub operating assembly engaging element 411 may be supported by a support 412 for the hub operating assembly engaging element. This support 412 may be able to move perpendicularly in the Z direction along the guide 416.

[0072] The lateral support 410 may include a frame 413 on which the vertical guide system 415 is arranged. The frame 413 can support, for example, the vertical guide 416. In addition to, or instead of, the vertical guide 416, a rail 417 may be provided. The frame 413 can support the rail 417. The support 412 for the engaging element 411 for the hub operating assembly 430 can slide vertically on the rail 417.

[0073] The frame 413 may include vertical beams 418 and horizontal beams 419 and have, for example, a rectangular shape. The height of the frame 413 may be the maximum height (length along the Z-axis) of the lateral support 410, but may be sufficient to vertically raise and rotate the hub 110 attached to the generator 3 for the direct-drive wind turbine. Such a height may be 10 to 15 meters in some examples.

[0074] The frame 413 may include a cap 414, which is the top of the frame 413. The cap 414 may include one or more actuators for moving the hub operating assembly engaging element 411 up and down. For example, a motor can rotate a vertical guide 416, moving the support 412 of the engaging element 411, and thus the element 411, vertically to engage with the hub operating assembly 430.

[0075] The support 412 for the hub operating assembly engaging element 411 may include one or more actuators, such as a motor or a hydraulic linear actuator, for moving the hub operating assembly engaging element 411 along the Y-axis and X-axis.

[0076] In this way, the hub operating assembly 430 can be rotated and moved in any direction, and the hub 110 held by the hub operating assembly can be reliably brought close to and joined to the generator 3.

[0077] The lateral support 410 may further comprise one or more reinforcing structures 420. To enhance the stability and robustness of the frame, and therefore the lateral support 410, the reinforcing structures 420 may be attached to the frame 413. The reinforcing structures 420 may have a triangular shape and may comprise horizontal beams 419 and inclined beams 421.

[0078] The width (length along the X direction, see Figure 7) of the lateral support 410 for the hub operating assembly 430 may be 10 to 20 meters, for example 13 to 17 meters, in some examples. The two lateral supports 410 may be substantially equal with respect to the guide system 415, frame 413, and reinforcing members 420. The distance between the two lateral supports 410 (which hold the hub operating assembly 430 along the Y direction, see Figure 6) may be 15 to 30 meters, for example 20 to 25 meters, in some examples.

[0079] Perspective views of an example of a hub operating assembly 430 can be seen in Figures 6 and 8. The hub operating assembly 430 may have a base 431. The base 431 may have an annular or similar shape. The base may be formed by several substantially linear segments joined at their longitudinal ends. The hub operating assembly, in particular the base, may be configured to surround the hub 110 of a direct-drive wind turbine 160.

[0080] The hub operating assembly 430 may include one or more hub engagement pins 440. The pins 440 are configured to grip and support the wind turbine hub 110. The pins 440 can clamp the hub 110. The pins 440 may be configured to mate with a receptacle on the hub. Three hub engagement pins 440 can be seen in Figures 6, 8, and 9. The hub engagement pins 440 may be attached to the hub operating assembly base 431 by supports 442 for the hub engagement pins 440. The supports 442 for the hub engagement pins 440 may include one or more actuators for moving the pins 440 closer to 451 and further away from 452 the hub 110. In some examples, the pins 440 can be actuated hydraulically or electrically.

[0081] Figure 6 shows a top view of the tool 400 that holds the hub 110. In this figure, the orientations related to the hub operating assembly 430 can be seen. The axis of rotation 460 defines the first direction, namely the Y' direction. The Y' axis may coincide with the Y axis. The second and third directions perpendicular to the Y' direction are the X' and Z' directions. In Figure 6, the X' and Z' axes coincide with the X and Z axes, respectively. However, this coincidence does not apply when the hub operating assembly 430 rotates, because the X' and Z' axes rotate around the Y' axis.

[0082] The rotation axis or Y' axis divides the hub operating assembly into two parts: a first part 472 and a second part 471. If the hub operating assembly 430 supports the generator 3 and the hub 110 and mounts them to the main frame 16 substantially horizontally (for example, the Z' axis in Figure 9 is parallel to the X axis in Figure 6), then the second part 471 may primarily support the weight of the hub and the generator. For this reason, the first part 472 may be referred to as the upper part and the second part 471 as the lower part.

[0083] The hub operating assembly 430 may further include a reinforcing bar 445 between two consecutive engagement pins 440 (see Figures 6 and 8). The reinforcing bar 445 may be provided to assist in supporting the hub 110 and the generator 3. The reinforcing bar 445 may be provided in the second portion (lower part) 471 of the hub operating assembly 430.

[0084] The support 442 of the pin 440 may extend in the Z' direction, particularly in the +Z' direction (towards the reader in Figure 9). When the hub 110 or the hub 110 attached to the generator 3 rises or falls, having the engagement pin 440 above the base 431 allows the force applied to the engagement pin 440 by the hub to be directed toward the base 431, thus assisting in supporting and stabilizing the load.

[0085] The engaging pins 440 may be equipped with ball joints 441 (see Figures 6 and 8). In particular, each engaging pin 440 may be equipped with a ball joint 441. The ball joint 441 can help improve contact between the engaging pin 440 and the hub 110. The ball joint 441 can also help absorb the load applied to the engaging pin 440 when, for example, the hub and the generator are rotated.

[0086] The tool 400 may include one or more sensors 443 configured to detect the generator 3 and / or the hub 110. For example, the engagement pins 440, in particular each engagement pin 440, may include one or more sensors 443. The sensors 443 may be included in a support for the engagement pins. One or more sensors 443 can be used when lowering the hub operating assembly 430 to grip the hub 110. The sensors 443 can help to precisely position the hub operating assembly 430 and the engagement pins 440 around the hub 110. The sensors may include a camera and / or a laser.

[0087] To assist in positioning the hub operating assembly 430 in the desired location, one or more sensors 443 may be provided on the hub operating assembly 430. For example, a laser and / or camera may be provided on the hub operating assembly base 431 so that the position of the hub relative to the generator can be determined. The sensors can detect the generator. These sensors 443 can also assist in correctly attaching the hub operating assembly pins 440 to the hub 110. Sensors suitable for measuring distance may be used.

[0088] The pins 440 may be arranged at substantially equal intervals around the hub operating assembly 430. For example, if there are three engagement pins, two consecutive pins may be spaced about 120 degrees apart around the base 231. The pins 440 may be configured to grip the hub 110 between the hub openings for mounting the wind turbine blades 120. The area of ​​the hub between these openings can provide sufficient robustness and rigidity for support or against forces and loads when rotating the hub and generator without being subjected to deformation.

[0089] The two pins 440 may be located in the second part 471 of the hub operating assembly. When the hub generator assembly is rotated and the set is positioned for mounting to the main frame 16, the two pins 440 may be located below the hub 110 and the generator 3, thereby improving the support and stabilization of the hub generator assembly. The two pins 440 of the second part 471 may be specifically configured to support a compressive load during rotation of the hub generator assembly.

[0090] One of the pins 440 may be located in the first part 472 of the hub operating assembly. This pin may be configured to hold the hub 110 in place during rotation of the hub generator assembly 5 and to compensate for any possible deflection of the assembly during rotation.

[0091] This specification discloses the present invention, including preferred embodiments, by example, and enables a person skilled in the art to practice the invention, including by constructing and using any device or system and by performing any incorporated method. The patentable scope of the present invention is defined by the claims and may include other examples that a person skilled in the art may conceive. Such other examples are intended to be within the claims if they have structural elements that do not differ from the wording of the claims, or if they include equivalent structural elements that do not substantially differ from the wording of the claims. A person skilled in the art may construct further embodiments and techniques in accordance with the principles of this application by combining and adapting aspects from the various embodiments described above and other known equivalents for each such aspect. Where reference numerals related to the drawings are placed in parentheses within the claims, those reference numerals are merely for clarity of the claims and should not be construed as limiting the claims. [Explanation of Symbols]

[0092] 1 frame 3 Generators 4 bolts, fasteners 5 Hub Generator Assembly 11 Front frame, main frame, protruding part, front 12 External structure 13 Inner structure 15 Pair of bearings 16 Main frame, rear 17 Bed Plate 18. Tapered Region 31 Generator Rotor 32 Generator Stator 35 Support structure, generator support 110 Hub 111 Space, Inside 115 Rotor 120 rotor blades, wind turbine blades 150 Support surface 160 Wind Turbine 161 Nacer 170 Wind Turbine Towers 180 Wind Turbine Controller 200 ways 231 Base 300 ways 400 Tools 401 Lateral supports 410 Lateral supports 411 Rotating element, hub operating assembly engaging element 412 Support 413 frames 414 Cap 415 Vertical Guide System 416 Vertical Guide 417 Rail 418 Vertical beam 419 Horizontal beam 420 Reinforcement structure, reinforcement material 421 Inclined beam 430 Hub Operating Assembly 431 Hub Operating Assembly Base 435 Arm 440 Hub Engagement Pins, Hub Operating Assembly Pins 441 Ball joint 442 Support 443 Sensor 445 Reinforcement, reinforcement bar 460 Rotation axis 471 Part 2 472 Part 1 RA rotation axis

Claims

1. providing a wind turbine hub (110), a main frame (16), and a generator (3) (step 210); vertically moving at least one of the wind turbine hub (110) and the generator (3) towards the other of the wind turbine hub (110) and the generator (3) (step 220); attaching the wind turbine hub (110) and the generator (3) to form a hub-generator assembly (5) (step 230); rotating the hub-generator assembly (5) while gripping the wind turbine hub (110) (step 240); and attaching the hub-generator assembly (5) to the main frame (16) (step 250). A method (200) comprising the above steps.

2. The method (200) according to claim 1, wherein the vertically moving step (220) includes lowering the wind turbine hub (110) towards the generator (3).

3. The method (200) according to claim 1, wherein the step of providing the generator (3) (step 210) includes providing the generator (3) mounted on a front frame (11), and the front frame (11) is configured to be attached to the main frame (16).

4. The method (200) according to claim 3, wherein the front frame (11) includes a portion (13) configured to support the generator (3) and a portion (12) configured to be attached to the wind turbine hub (110).

5. The method (200) according to claim 1, further including a step of raising the hub-generator assembly (5) before the step of rotating the hub-generator assembly (5) (step 240).

6. The method (200) according to claim 1, wherein the hub-generator assembly (5) is rotated at 70 to 110 degrees, specifically 80 to 100 degrees.

7. The method (200) according to any one of claims 2 to 6, wherein the step of lowering the wind turbine hub (110) includes gripping the hub (110).

8. The method (200) according to claim 7, wherein the gripping step includes clamping the hub (110) at two points between hub openings for attaching wind turbine blades (120). **Claim 9**: A tool (400) for operating a wind turbine hub (110) and a hub generator assembly (5), wherein the hub generator assembly (5) is formed by attaching the wind turbine hub (110) to a wind turbine generator (3), the tool (400) comprising: a hub operating assembly (430) configured to grip the hub (110); two lateral supports (410) for supporting the hub operating assembly (430) therebetween (410); and the hub operating assembly (430) is configured to be displaced vertically along the lateral supports (410) to move the wind turbine hub (110) and the hub generator assembly (5) vertically while gripping the wind turbine hub (110), and to rotate about the lateral supports (410) to rotate the hub generator assembly (5) while gripping the wind turbine hub (110) (240). **Claim 10**: The tool (400) according to claim 9, wherein the hub operating assembly (430) is configured to surround the hub (110). **Claim 11**: The tool (400) according to claim 10, wherein the hub operating assembly (430) comprises a base (431) and two arms (435) attached to both sides of the base (431), and the arms (435) are movably connected to the lateral supports (410). **Claim 12**: The tool (400) according to claim 10, wherein the hub operating assembly (430) comprises one or more hub engagement pins (440) for mating with receptacles of the hub (110). **Claim 13**: The tool (400) according to claim 10, wherein the lateral support (410) comprises an element (411) configured to engage and rotate the hub operating assembly (430). **Claim 14**: The tool (400) according to claim 13, wherein the lateral support (410) further comprises a vertical guide system (415) configured to vertically move the element (411) configured to engage and rotate the hub operating assembly (430). **Claim 15**: The tool (400) according to any one of claims 9 to 14, further comprising one or more sensors (443) configured to detect the hub (110) and / or the wind turbine generator (3).

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