Armature assembly for power generator, and assembly method

Abstract

To provide an armature assembly for assembling a permanent magnet power generator for a wind turbine, and a method for operating the armature assembly.SOLUTION: The present disclosure relates to an armature assembly for assembling a permanent magnet electric machine, and a method for assembling the permanent magnet electric machine. The armature assembly comprises an armature having a plurality of coils. The armature assembly further comprises a power supply and a control system constituted to selectively supply power to the plurality of coils when one of a field magnet with one or more permanent magnets and the armature approaches the other of the field magnet and the armature during assembly of the permanent magnet electric machine. The permanent magnet electric machine may be a permanent magnet power generator for a wind turbine, especially a direct drive wind turbine.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to armature assemblies for electromechanical devices and methods for operating them. More particularly, the present disclosure relates to armature assemblies for assembling permanent magnet generators for wind turbines and methods for operating armature assemblies.

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 usually generates torque that is transmitted directly ( "direct drive" or "gearless") through the rotor shaft to the generator or through a gearbox. In this way, the generator generates electricity that can be supplied to the power grid.

[0003] The wind turbine hub may be rotatably coupled to the front of the nacelle. The wind turbine hub can be connected to a rotor shaft, which can then be rotatably mounted within the nacelle using one or more rotor shaft bearings disposed inside the nacelle. The nacelle is, for example, a housing disposed at the top of a wind turbine tower that typically houses and protects additional components such as a gearbox (if present) and a generator, as well as a power converter and auxiliary systems, depending on the wind turbine.

[0004] The generator can have a field and an armature, the field being configured to generate a magnetic field and the armature being configured to support a voltage induced in its windings due to a time-varying magnetic field generated by the relative movement of the armature and the field. In one example, the armature may be stationary during operation and the field may be rotatable, for example, by a shaft. The shaft may be the rotor shaft of the wind turbine rotor.

[0005] The field can include permanent magnets. Permanent magnet generators are considered more reliable and require less maintenance than other types of generators. They may be particularly suitable for offshore wind turbines. The permanent magnets may be provided in a permanent magnet module, which can be mounted on the field as a single piece. The permanent magnet module can be located on the outer or inner circumference of the rim of the field.

[0006] A permanent magnet module may be defined as a unit having multiple permanent magnets, so that the multiple magnets can be mounted and unmounted together. Such a module may have a module base having a shape suitable for housing or receiving multiple permanent magnets. The magnets may be fixed to the base in various ways. The base may be configured to be fixed to a field rim, for example, a rotor rim, so that the multiple magnets are fixed together to the field rim through the module base. The use of a permanent magnet module can facilitate the manufacture of a generator field.

[0007] Whether or not permanent magnets are grouped into modules, magnets are typically arranged to generate magnetic flux that travels a path across the air gap between the field, for example, the rotor's permanent magnets and the armature, for example, the stator's coils, thereby reaching the armature and being affected by the magnetic flux.

[0008] It is known that large electromachines, such as direct-drive wind turbine generators, can be assembled by carrying the rotor inside the stator, or vice versa. After the field and armature have already been integrated, the magnets can be magnetized and attached to the field. Since these steps are performed on the main production line of the generator, this can be a relatively slow and time-consuming process.

[0009] A faster assembly process can be enabled by attaching permanent magnets to the field before the field and armature come into contact. For example, a rotor with already magnetized magnets can be placed on top of a stator with coils. However, the presence of already magnetized magnets can cause the field to magnetically attract the armature quite strongly. A magnetic field exceeding 1 Tesla can be generated between the armature and the field. The magnetic force between the armature and the field may exceed 400,600 kN or more. Therefore, the possibility of deforming and damaging the stator and / or rotor can increase with this option. The presence of already magnetized magnets in the field can complicate the integration of the armature and field in an effective, easy, rapid, and safe manner.

[0010] While this disclosure focuses on wind turbine generators, particularly permanent magnet generators for direct-drive wind turbines (which are much larger and heavier than the generators used in wind turbines with gearboxes), similar problems and challenges can arise in other electromechanical assemblies. [Overview of the Initiative]

[0011] In one aspect of the present disclosure, an armature is provided. The armature assembly comprises an armature including a plurality of coils. The armature assembly further comprises a power supply and control system configured to selectively supply the plurality of coils when one of a field and armature, comprising one or more permanent magnets, approaches the other of the field and armature during the assembly of a permanent magnet electromachine. The electromachine may be a permanent magnet generator for a wind turbine, in particular a direct-drive wind turbine.

[0012] According to this embodiment, an electric current can be injected into the armature to generate a magnetic field that opposes (in direction) the magnetic field generated by the permanent magnets. Thus, the resulting overall magnetic field can be reduced, and the attractive force between the field and the armature, which has magnetized permanent magnets, can be reduced and compensated for. Thus, deformation and damage to the rotor and / or stator can be avoided during the assembly process.

[0013] The generator assembly process can be faster because the magnets can be bonded to the outer field of the generator's main production line. Furthermore, quality inspection and control during field pre-assembly can be easier if performed before bonding to the armature.

[0014] In a further embodiment, a method is provided for assembling a generator rotor and a generator stator supporting permanent magnets. The method includes moving at least one of the generator rotor and the generator stator toward the other of the generator rotor and the generator stator. The method further includes simultaneously supplying power to the armature of the generator stator.

[0015] In yet another embodiment, another method is provided for assembling a permanent magnet generator comprising an armature and field for a wind turbine. The method includes lowering the field axially and vertically toward the armature. The method further includes injecting current into the armature while the field is being lowered. [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. [Figure 3] This diagram schematically shows a side view of an example of an armature assembly. [Figure 4] This diagram schematically shows a side view of an example in which a generator rotor equipped with a field magnet and a generator stator equipped with an armature are located close together. [Figure 5] This diagram schematically shows a perspective view of an example of a generator stator with an armature supported by a frame. [Figure 6] This diagram schematically illustrates one example of a method for assembling a permanent magnet generator for wind turbines. [Figure 7] This diagram schematically illustrates another example of a method for assembling a permanent magnet generator for a wind turbine. [Modes for carrying out the invention]

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

[0018] While an example of an armature for a wind turbine generator is specifically shown, the same or similar armature assemblies and methods can be used for other applications.

[0019] Figure 1 is a perspective view of an example of a wind turbine 10. In this example, the wind turbine 10 is a horizontal-axis wind turbine. Alternatively, the wind turbine 10 may be a vertical-axis wind turbine. In this example, the wind turbine 10 includes a tower 100 extending from a support system 14 on the ground 12, a nacelle 16 mounted on the tower 100, and a rotor 18 coupled to the nacelle 16. The rotor 18 includes a rotatable hub 20 and at least one rotor blade 22 coupled to the hub 20 and extending outward from the hub 20. In this example, the rotor 18 has three rotor blades 22. In an alternative embodiment, the rotor 18 includes more or fewer than three rotor blades 22. The tower 100 can be fabricated from tubular steel to define a cavity (not shown in Figure 1) between the support system 14 and the nacelle 16. In an alternative embodiment, the tower 100 is any suitable type of tower having any suitable height. In alternative configurations, the tower may be a hybrid tower comprising concrete and tubular steel sections. Alternatively, the tower may be a partially or fully lattice tower.

[0020] The rotor blades 22 may be spaced apart around the hub 20 to facilitate the rotation of the rotor 18 and to allow kinetic energy to be transferred from the wind to usable mechanical energy, and subsequently to electrical energy. The rotor blades 22 are fitted to the hub 20 by coupling the blade root portion 24 to the hub 20 with a plurality of load transfer regions 26. The load transfer regions 26 may have hub load transfer regions and blade load transfer regions (neither of which are shown in Figure 1). The load induced on the rotor blades 22 is transferred to the hub 20 via the load transfer regions 26.

[0021] In an example, the rotor blade 22 can have a length ranging from about 15 meters (m) to about 90 m or more. The rotor blade 22 may have any suitable length that enables the wind turbine 10 to function as described herein. For example, non-limiting examples of blade lengths include lengths less than 20 m, 37 m, 48.7 m, 50.2 m, 52.2 m, or greater than 91 m. When wind hits the rotor blade 22 from the wind direction 28, the rotor 18 rotates about the rotor shaft 30. When the rotor blade 22 rotates and is subject to centrifugal force, the rotor blade 22 also receives various forces and moments. Thus, the rotor blade 22 can deflect and / or rotate from a neutral or non-deflected position to a deflected position.

[0022] Furthermore, the pitch angle of the rotor blade 22, i.e., the angle that determines the orientation of the rotor blade 22 with respect to the wind direction, is changed by the pitch system 32, and by adjusting the angular position of at least one rotor blade 22 with respect to the wind vector, the load and power generated by the wind turbine 10 can be controlled. The pitch axis 34 of the rotor blade 22 is also shown. During operation of the wind turbine 10, the pitch system 32 can specifically change the pitch angle of the rotor blade 22 such that the angle of attack of (a part of) the rotor blade is reduced, thereby facilitating a reduction in the rotational speed and / or facilitating a stall of the rotor 18.

[0023] In this example, the blade pitch of each rotor blade 22 is individually controlled by the wind turbine controller 36 or the pitch control system 80. Alternatively, the blade pitch for all rotor blades 22 may be controlled simultaneously by the said control system.

[0024] Furthermore, in this example, as the wind direction 28 changes, the yaw direction of the nacelle 16 can be rotated about the yaw axis 38 to position the rotor blade 22 with respect to the wind direction 28.

[0025] In this example, the wind turbine controller 36 is shown as being concentrated within the nacelle 16, but the wind turbine controller 36 may be a distributed system located throughout the wind turbine 10, on the support system 14, within the wind power plant, and / or in a remote control center. The wind turbine controller 36 includes a processor 40 configured to carry out the methods and / or steps described herein. Furthermore, many of the other components described herein include processors.

[0026] As used herein, the term “processor” is not limited to integrated circuits referred to as computers in the prior art, but broadly includes controllers, microcontrollers, microcomputers, programmable logic controllers (PLCs), application-specific integrated circuits, and other programmable circuits, and these terms are used interchangeably herein. It should be understood that processors and / or control systems may also include memory, input channels, and / or output channels.

[0027] Figure 2 is an enlarged cross-sectional view of a portion of the wind turbine 10. In this example, the wind turbine 10 includes a nacelle 16 and a rotor 18 rotatably coupled to the nacelle 16. More specifically, the hub 20 of the rotor 18 is rotatably coupled to an electric generator 42 positioned within the nacelle 16 by a main shaft 44, a gearbox 46, a high-speed shaft 48, and a coupling 50. In this example, the main shaft 44 is positioned at least partially coaxial with the longitudinal axis (not shown) of the nacelle 16. The rotation of the main shaft 44 drives the gearbox 46, which in turn drives the high-speed shaft 48 by converting the relatively slow rotational motion of the rotor 18 and the main shaft 44 into the relatively fast rotational motion of the high-speed shaft 48. The latter is connected to the generator 42 to produce electrical energy with the help of the coupling 50. Furthermore, a transformer 90 and / or appropriate electronic equipment, switches, and / or an inverter can be placed in the nacelle 16 to convert the electrical energy generated by the generator 42, which has a voltage of 400V to 1000V, into electrical energy having a medium voltage (10 to 35kV). The electrical energy is then conducted from the nacelle 16 to the tower 100 via power cables.

[0028] The gearbox 46, generator 42, and transformer 90 may be supported by the main support structure frame of the nacelle 16, or optionally embodied as the main frame 52. The gearbox 46 may include a gearbox housing connected to the main frame 52 by one or more torque arms 103. In this example, the nacelle 16 also includes a main front support bearing 60 and a main rear support bearing 62. Furthermore, the generator 42 may be mounted to the main frame 52 by isolation support means 54, in particular to prevent vibrations of the generator 42 from being introduced into the main frame 52 and thereby causing a noise emission source.

[0029] Optionally, the main frame 52 is configured to bear the weight of the components of the rotor 18 and nacelle 16, as well as the entire load caused by the wind and rotational load, and further to introduce these loads into the tower 100 of the wind turbine 10. The rotor shaft 44, generator 42, gearbox 46, high-speed shaft 48, coupling 50, and any associated fastening, support, and / or fixing devices, including but not limited to supports 52, front support bearings 60, and rear support bearings 62, may be referred to as the drivetrain 64.

[0030] In some examples, the wind turbine may be a direct-drive wind turbine without a gearbox 46. The generator 42 operates at the same rotational speed as the rotor 18 in the direct-drive wind turbine. Therefore, they generally have a much larger diameter than the generators used in wind turbines with a gearbox 46 in order to provide a similar amount of power as wind turbines with a gearbox.

[0031] The nacelle 16 may also include a yaw drive mechanism 56 that can be used to rotate the nacelle 16 and, consequently, the rotor 18 around the yaw axis 38, thereby controlling the viewpoint of the rotor blades 22 with respect to the wind direction 28.

[0032] To properly position the nacelle 16 with respect to the wind direction 28, the nacelle 16 may also include at least one weather measurement system, which may include a wind vane and an anemometer. The weather measurement system 58 can provide the wind turbine controller 36 with information, which may include wind direction 28 and / or wind speed. In this example, the pitch system 32 is at least partially located within the hub 20 as a pitch assembly 66. The pitch assembly 66 includes one or more pitch drive systems 68 and at least one sensor 70. Each pitch drive system 68 is coupled to each rotor blade 22 (shown in Figure 1) to modulate the pitch angle of the rotor blade 22 along the pitch axis 34. Only one of the three pitch drive systems 68 is shown in Figure 2.

[0033] In this example, the pitch assembly 66 includes a hub 20 and at least one pitch bearing 72 coupled to each rotor blade 22 (shown in Figure 1) to rotate each rotor blade 22 around a pitch axis 34. The pitch drive system 68 includes a pitch drive motor 74, a pitch drive gearbox 76, and a pitch drive pinion 78. The pitch drive motor 74 is coupled to the pitch drive gearbox 76 so that the pitch drive motor 74 imparts mechanical force to the pitch drive gearbox 76. The pitch drive gearbox 76 is coupled to the pitch drive pinion 78 so that the pitch drive pinion 78 is rotated by the pitch drive gearbox 76. The pitch bearing 72 is coupled to the pitch drive pinion 78 so that the rotation of the pitch drive pinion 78 causes the rotation of the pitch bearing 72.

[0034] The pitch drive system 68 is coupled to the wind turbine controller 36 to adjust the pitch angle of the rotor blades 22 upon receiving one or more signals from the wind turbine controller 36. In this example, the pitch drive motor 74 is any suitable motor driven by a power and / or hydraulic system that enables the pitch assembly 66 to function as described herein. Alternatively, the pitch assembly 66 may include any suitable structure, configuration, arrangement, and / or component, but is not limited to, a hydraulic cylinder, spring, and / or servo mechanism. In a particular embodiment, the pitch drive motor 74 is driven by energy extracted from a stored energy source (not shown) that supplies the rotational inertia and / or energy of the hub 20 to the components of the wind turbine 10.

[0035] The pitch assembly 66 may also include one or more pitch control systems 80 for controlling the pitch drive system 68 in accordance with control signals from the wind turbine controller 36 in certain priority situations and / or during rotor overspeed. In this example, the pitch assembly 66 includes at least one pitch control system 80 communicably coupled to each pitch drive system 68 in order to control the pitch drive system 68 independently of the wind turbine controller 36. In this example, the pitch control system 80 is coupled to the pitch drive system 68 and the sensor 70. During normal operation of the wind turbine 10, the wind turbine controller 36 can control the pitch drive system 68 to adjust the pitch angle of the rotor blades 22.

[0036] According to one embodiment, for example, a power generator 84 comprising a battery and an electric capacitor is located in or within the hub 20 and coupled to the sensor 70, the pitch control system 80, and the pitch drive system 68 to provide a power source to these components. In this example, the power generator 84 provides a continuous power source to the pitch assembly 66 during the operation of the wind turbine 10. In an alternative embodiment, the power generator 84 provides power to the pitch assembly 66 only during power loss events of the wind turbine 10. Power loss events may include power grid loss or depletion, malfunction of the wind turbine 10's electrical system, and / or failure of the wind turbine controller 36. During a power loss event, the power generator 84 operates to provide power to the pitch assembly 66 so that the pitch assembly 66 can operate during the power loss event.

[0037] In this example, the pitch drive system 68, sensor 70, pitch control system 80, cable, and power generator 84 are each positioned within a cavity 86 defined by the inner surface 88 of the hub 20. In an alternative embodiment, the components may be positioned relative to the outer surface of the hub 20 and coupled directly or indirectly to the outer surface.

[0038] One aspect of the present disclosure provides an armature assembly 300. The armature assembly 300 comprises an armature 310 including a plurality of coils 315. The armature assembly 300 further comprises a power supply 330 and a control system 335 configured to selectively supply power to the plurality of coils 315 when one of the field 320 and the armature 310, which comprises one or more permanent magnets 325, approaches the other of the field 320 and the armature 310 during the assembly of the permanent magnet electromachine. The permanent magnet electromachine may be a permanent magnet generator for a wind turbine 10, more particularly for a direct-drive wind turbine.

[0039] Figures 3 and 4 show an example of an armature assembly 300 in which the armature 310 is mounted on the generator stator 307. In other examples, the armature 310 may be mounted on the generator rotor 317.

[0040] The coils 315 of the armature 310 may be grouped into windings. A winding can be understood as an electrical conductor included in the armature, for example, a wire. A winding may be wound, for example, to form turns around an armature tooth. A group of turns may be called a coil. Thus, a winding may consist of one or more coils. For example, a winding may consist of 15 coils, each coil being wound around an armature tooth.

[0041] The armature 310 may have two or more windings. For example, the armature 310 may have three, six, nine, or more windings. Each winding may be configured to provide an electrical phase that is typically different from other electrical phases.

[0042] Figure 4 shows how the field 320 and armature 310 (i.e., the rotor 317 with the field 320 and the stator 307 with the armature 310) can be located in close proximity. In Figure 4, the field 320 is located in the rotor 317, but in other examples, the field 320 may be located in the stator 307.

[0043] The assembled rotor 317 and stator 307 in Figure 4 form a radial field electromachine, but the present disclosure may also be applicable to axial field or transverse field electromachines.

[0044] As shown in Figure 4, the field 320 can be lowered, for example, vertically and axially 350, so that the field 320 radially surrounds the armature 310. In some other examples, the field 320 may be configured to be mounted radially inward of the armature 310. In some examples, the armature 310 may be lowered toward the field 320.

[0045] In some other examples, the field 320 and armature 310 may be arranged side by side or configured to approach each other in any suitable direction. Generally, one or both of the field 320 and armature 310 can be moved toward the other.

[0046] When a field 320 comprising one or more permanent magnets 325 and an armature 310 is assembled, a magnetic attractive force may be generated between the field 320 and the armature 310. For example, when the permanent magnets 325 in the field 320 and the coils 315 in the armature 310 begin to face each other or begin to align in the radial direction 355, a magnetic attractive force may be generated in the radial direction 355.

[0047] In some examples, for instance, the air gap 370 between the field 320 and the armature 310 in the radial direction 355 may be less than 10 mm, for example, 5-7 mm. Thus, very strong magnetic fields can be generated between these structures, reaching and exceeding 1T. Consequently, the field 320 and / or armature 310 may deform, even collide with each other, and be damaged, potentially destroying the assembly of the generator 42.

[0048] The circulating current along the armature 310 while the field magnet 320 and armature 310 are in close proximity can generate a magnetic field in the opposite direction to the magnetic field generated by the permanent magnet. The resulting overall magnetic field, and therefore the magnetic attractive force between these structures, can also be reduced, enabling a more efficient and safer assembly of the generator 42.

[0049] The power supply 330 may be configured to supply power to the coil 315 of the armature 310. The power supply can include any suitable electric battery of any kind. In some examples, a converter can be used to supply power to the coil 315.

[0050] The power supply 330 may be connected to the coil 315. The connection may require, for example, two wires or cables, one for guiding the current towards the coil and the other for guiding the current out of the coil to close the electrical circuit.

[0051] The power supply 330 can supply power to one or more windings of the armature 310. In some examples, the current can circulate simultaneously through all the windings of the armature 310. In some other examples, the current can circulate simultaneously through some, but not all, of the windings of the armature 310. In any example, the current can circulate simultaneously through at least partially two or more windings.

[0052] More than one power supply may be used to power the windings. For example, the number of power supplies may be equal to the number of windings in the armature 310. In this example, each winding has its own dedicated power supply 330.

[0053] It may also be possible to use one or more switches to change which winding receives power.

[0054] The armature 310 may be supplied with either DC or AC current. In the case of DC current, the amplitude and direction of the supply current circulation may be adapted to generate a magnetic field in the opposite direction to the magnetic field generated by the permanent magnet, thereby canceling out the attractive force between the armature 310 and the field 320.

[0055] In some examples, the armature 310 may be divided into two or more sectors 365. A sector 365 (see Figure 5) can be understood as part of the armature 310 comprising multiple coils 315. The coils may be continuous. A sector 365 may be supplied independently from the other sectors by a power supply 330. Control of the distance between the armature 310 and the field 320, for example, the air gap 370, can be enhanced in this way. In some examples, a sector 365 may contain only one coil. It may be possible to supply power to all or only a portion of the windings of the sector.

[0056] The control system 335 is configured to control the current injected into the multiple coils 315 while the armature 315 and field 320 are in contact. The control system 335 may include a controller, which may comprise memory and a processor. The memory may contain instructions that are read and executed by the processor. The memory may also contain data, such as data measured by one or more sensors with respect to the field 320 and / or armature 310. The processor can read and execute instructions stored in memory. The controller may be a main controller.

[0057] The control system 335, for example, the controller, can be communicatively coupled to the power supply 330. If there are additional power supplies, the control system 335 may be communicatively coupled to some or all of the additional power supplies. The control system 335 can indicate to one or more power supplies the voltage applied to the windings or the current supplied to the windings.

[0058] The control system 335 can indicate the amplitude and / or direction of current circulation. The control system 335 can indicate which winding is supplied and for how long. Multiple supplies can be supplied to the same winding while the field 320 and armature 310 are being assembled.

[0059] The control system may have additional controllers to adjust the current circulation through the windings while the field 320 and armature 310 are approaching. For example, a local controller may be provided for each winding. A local controller may also control two or more windings. In one example, the armature 310 may have six windings, and a first local controller may be configured to control three of the windings, and a second controller may be configured to control the remaining three windings. Similarly, a local controller may be provided for controlling a specific sector 365 of the armature 310.

[0060] The armature assembly 300 may further comprise one or more sensors 340. The control system 335 can be configured to control the current injected into the armature 310 based on measurements provided by one or more sensors.

[0061] One or more sensors 340 may be configured to determine the distance between the armature 310 and the field 320 at one or more locations. This distance may be the air gap 370. The distance may be a horizontal distance or a radial distance. In an example, multiple sensors 340 may be placed around the circumference of the rotor and / or stator to determine whether the air gap is constant along the circumference. If a deviation is measured, a current may be injected to compensate for such deviation. The vertical distance or axial distance between the armature 310 and the field 320 may be determined additionally or alternatively.

[0062] Any suitable sensor can be used to detect how close the armature 310 and the field 320 are to each other, and in particular how close the magnetized permanent magnet and the coil are to each other. This distance can be determined in the direction in which the magnetic flux flows from the permanent magnet to the coil 315 once the armature 310 and the field 320 are assembled. In Figure 4, this direction is radial or horizontal 355.

[0063] The determination may be direct or indirect. A direct determination may include measuring the distance between the armature and the field. An indirect determination may include measuring a first distance between a reference and the field 320, and a second distance between the reference and the armature 310. The distance between the field 320 and the armature 310 can then be obtained from the first and second distances. The reference may be a sensor. An indirect determination may include measuring any suitable physical quantity (e.g., force) and determining the distance between the field and the armature, e.g., the air gap 370, from that value by either the sensor 340 or the control system 335.

[0064] The sensor may be connected to or mounted on the armature 310, the field 320, or a specific support. The specific support may not support or be connected to the armature 310, the field 320, or any of them.

[0065] The sensor 340 can be connected to the control system 335 in a communicative manner. When the sensor measures one or more values, the sensor can transmit the values ​​to the control system 335. The control system 335 can instruct the power supply 330 to modify the power supplied to the coil 315 of the armature 310. Modifying may include changing the magnitude of the voltage or current applied to one or more windings. Modifying may also include changing the direction of the current circulating through one or more windings. The magnitude and / or direction of the current may be modified.

[0066] Depending on the values ​​determined by one or more sensors 340, the control system 335 may instruct the power supply 330 to continue supplying power to one or more windings instead of changing the power.

[0067] If there are two or more sensors for measuring the distance between the armature 310 and the field 320, for example, the air gap 370, the above description also applies to other distance sensors.

[0068] For example, as shown in Figures 3 to 5, if the generator 42 is a radial machine, multiple distance sensors can be mounted in the tangential direction 360. They may be equally spaced. For example, six distance sensors may be mounted around the armature 310 (or field 320), and the space between any two consecutive sensors at any position along the tangential direction 360 may be 60°.

[0069] The armature assembly 300 may include one or more sensors 345 configured to determine the torque exerted on either the field or the armature. When the armature 310 and the field 320 come into close proximity, the magnetic force between them can cause the armature 310 and / or the field 320 to rotate relative to the other. For example, in Figure 4, the field 320 and / or the armature 310 may begin to rotate tangentially 360. Such rotation (and possibly some deformation in other directions) can be stopped or reduced at least partially by a structure or frame 380 that holds the components, such as an armature frame. However, this may not be sufficient to avoid deformation due to magnetic attraction and to allow for accurate and effective assembly of the field 320 and the armature 310.

[0070] Sensor 345 for determining the torque or rotation of one of the armature 310 and field 320 relative to the other can provide direct or indirect determination. Indirect determination may include measuring one or more appropriate physical quantities and extracting a torque value therefrom. In some examples, angular velocity can be measured. One or more values ​​measured or determined by sensor 345 can be transmitted to a control system, for example, a controller. Such a controller may be a main controller or another controller.

[0071] The torque sensor 345 may comprise a load cell or a linear or angular encoder. Other torque sensors are also possible. The torque sensor may be mounted or connected to the field 320 or armature 310. For example, the torque sensor may be mounted or connected to a structure (armature 310 or field 320) configured to move toward another structure (field 320 or armature 310). Two or more torque sensors may be used.

[0072] A controller, for example, a main controller, can adjust the power supplied to one or more windings according to torque values ​​received or determined from one or more torque sensors. If a support or frame supports or holds the field 320 or armature 310, the support can be moved, for example, rotated, to compensate for the torque.

[0073] The armature assembly 300 may further comprise an armature frame or mechanical reinforcement 380 configured to hold the armature 310. An example of such a frame 380 is shown in Figure 5. In this example, the frame 380 is configured to avoid, or at least reduce, the deformation that the armature 310 undergoes when approaching the field 320. The armature frame 380 may be configured to move the armature 310 toward the field 320.

[0074] Similarly, the armature assembly 300 may further comprise a field frame 390 configured to hold the field 320. The field frame may be configured to move the field 320 toward the armature 310. The field frame 390 may comprise, for example, two or more arms 395, and the arms 395 may comprise one or more clamps 396. The clamps 396 can hold the field 320 in order to lower it toward the armature 310, as shown in Figure 4. The arms 395 may allow the field 320 to rotate in the tangential direction 360. Such rotation can compensate for torque detected by one or more torque sensors 345.

[0075] The field frame 390 may include any components that allow the field 320 to be mechanically moved as needed to control the tangential movement of the field 320. For example, the field frame 390 may move according to previous measurements of one or more sensors, such as a load cell, to avoid or reduce rotation of the field 320 in the circumferential direction, such as the rotor. Any suitable sensor capable of measuring the displacement of the field 320 in the circumferential direction can be used.

[0076] The armature assembly 300 may further comprise a field 320 containing a plurality of permanent magnets. The magnets may be arranged within a magnet module. The permanent magnets are magnetized before they come into contact with the armature and the field.

[0077] In Figures 3 to 5, the generator is a wind turbine generator for a direct-drive wind turbine. The armature is mounted on the stator, but in other examples, the armature may be on the rotor. In Figure 4, the field is mounted on the rotor, but in other examples, the field may be on the stator.

[0078] Further aspects of this disclosure provide a method 400 for assembling a generator rotor 317 and a generator stator 307 supporting permanent magnets. Any armature assembly 300 described above can be used with respect to Figures 3 to 5.

[0079] The method involves moving at least one of the generator rotor 317 and the generator stator 307 toward the other in block 410. For example, at least one of the generator rotor and the generator stator may be moved along the axis of rotation of the generator rotor such that one of the generator rotor and the generator stator radially surrounds the other. The armature 310 and the field 320 can approach each other in the axial and vertical directions 350, as shown in Figure 4. At least one of the generator rotor 317 and the generator stator 307 may be moved vertically. In some other examples, they can approach each other in the axial and horizontal directions. In general, they can approach each other in any suitable direction.

[0080] In this specification, approaching should be understood as bringing the armature 310 and the field 320 closer to each other in order to assemble the generator 42. Approaching may include moving one of the armature 310 and the field 320 toward the other. For example, the field 320 may be moved toward the armature 310, as shown in Figure 4. Approaching may also include moving both the armature 310 and the field 320 toward the other.

[0081] The armature 310 and / or field 320 may be held by the frames 380, 390 during approach. For example, the mechanical reinforcement 380 may hold the armature 310 as shown in Figure 5 to reduce deformation of the armature 310 when the field 320 approaches the armature 310.

[0082] The frame 390 can move at least one of the generator rotor 317 and the generator stator 307. For example, the field frame 390, which has a plurality of arms 395 with clamps 396, can be used to hold and move the field 320. For example, the plurality of arms 395 with clamps 396 can move the field 320 toward the armature 310, for example, by lowering it, as shown in Figure 4. In other examples, such a frame can move the armature 310.

[0083] The method further includes simultaneously supplying power to the armature 310 of the generator stator 307 in block 420. One or more power supplies 330 may perform this task. The current does not necessarily have to be supplied from the start of the displacement of the rotor and / or stator. The supply of current can be started after a certain distance or position is reached between the field 320 and the armature 310, or after a certain value of a certain magnitude is reached.

[0084] The current injected into the armature may be either AC or DC. When DC current is used, positive and negative DC currents may be supplied to the armature 310. For example, a positive DC current may be supplied to one or more windings, and a negative DC current may be supplied to one or more different windings. The amplitude and direction of the current circulating through the windings may be selected to generate a magnetic field that counteracts the magnetic field generated by the permanent magnets and compensate for the magnetic attraction between the armature 310 and the field 320.

[0085] The distance between the generator rotor 317 and the generator stator 307 at one or more locations, for example, the radial distance, can be determined. The armature 310 may be powered at least partially based on the determined distance. The distance between the armature 310 and the field 320 may also be determined.

[0086] For example, the air gap 370 can be determined when the permanent magnet 325 begins to face the coil 315 in the radial direction 355. A distance sensor can determine such a distance 370 directly or indirectly. The control system 335 can receive information from one or more sensors 340, for example, one or more distance sensors, and indicate one or more power supplies 330 to correct or maintain the power supplied to the armature 310. The magnetic force generated by the current circulating through the windings of the armature 310 can cancel out the magnetic attractive force between the armature 310 and the field 320 in a controlled manner.

[0087] The armature 310 may be divided into two or more sectors 365 or parts. Part 365 of the armature 310 may be powered independently of other parts 365 of the armature 310. Control of the magnetic force between the armature 310 and the field 320, and therefore control of the assembly process, can be improved in this way.

[0088] The method may further include determining the torque applied to at least one of the generator rotor 317 and the generator stator 307, and supplying power to the armature 310 based at least in part on the determined torque. In other words, the rotation between the field 320 and the armature 310 can be measured. One or more torque sensors 345 can determine the torque directly or indirectly, and one or more controllers of the control system 335 can take this information into account when instructing one or more power supplies 330 to supply power to the armature 310.

[0089] The control system 330 may additionally or alternatively include actuators that mechanically counteract the detected torque. For example, an arm 370 that holds the field 320 can reduce the torque that rotates the field 320, thereby better controlling the proximity of the field 320 and the armature 310.

[0090] A further aspect of the present disclosure provides another method 500 for assembling a permanent magnet generator comprising an armature 310 and a field 320 for a wind turbine 10. Similar to method 400 described above, any armature assembly 300 described with respect to Figures 3 to 5 can be used.

[0091] The method includes lowering the field 320 axially and vertically toward the armature 310 in block 510. If the field 320 is included in the rotor 317, the rotor 317 can be lowered. The armature 310 may be held in place by mechanical reinforcement 380, for example, as shown in Figure 5. If the armature is provided in the stator 307, the stator is a stator held in place.

[0092] The method further includes injecting current into the armature 310 in block 520 while the field 320 is descending. The injected current may be a DC current. One or more power supplies 330 may inject current into the armature 310.

[0093] The method may further include determining the horizontal distance between the armature 310 and the field 320. The horizontal distance may be the air gap 370. One or more distance sensors 340 can detect the horizontal distance directly or indirectly.

[0094] The method may further include determining the torque of the field 320. One or more torque sensors 345 may be used to detect the torque.

[0095] The explanations provided with respect to Figures 3 to 5 can be applied to this method 500. Similarly, one or more embodiments of method 400 can be applied to method 500.

[0096] This specification discloses the present invention, including preferred embodiments, using examples, and enables a person skilled in the art to practice the invention, including by fabricating and using any device or system and by carrying out 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 are not different from the language of the claims, or if they include equivalent structural elements that do not substantially differ from the language 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 in the claims, those reference numerals are merely for clarity of the claims and should not be construed as limiting the claims. [Explanation of symbols]

[0097] 10 Wind Turbines 12 Ground 14 Support System 16 Nacer 18 rotors 20 Hubs 22 rotor blades 24. Base of the blade 26 Load transfer region 28 Wind direction 30 rotor shaft 32 Pitch System 34 Pitch axis 36 Wind Turbine Controller 38 Yaw axis 40 processors 42 Electric generators 44 Main shaft, rotor shaft 46 Gearbox 48 High-speed shaft 50 Couplings 52 Main frame, support 54 Separation support means 56 Yaw drive mechanism 58 Weather Measurement Systems 60 Main forward support bearing 62 Main rear support bearing 64 Drivetrain 66 Pitch Assembly 68 Pitch Drive System 70 sensors 72 pitch bearing 74 Pitch drive motor 76 Pitch Drive Gearbox 78 Pitch Drive Pinion 80 Pitch Control System 84 Power Generators 86 Hollow 88 Inner self 90 Transformer 100 Towers 103 Torque Arm 300 Armature Assembly 307 Generator Stator 310 Armature 315 Coils, armature 317 Generator Rotor 320 Field 325 Permanent Magnet 330 Power supply and control systems 335 Control System 340 sensors 345 Torque Sensor 350 vertical, axial 355 Radial, horizontal 360 tangential direction 365 sectors, part of the armature 370 Air gap, distance, arm 380 Armature frame, mechanical reinforcement 390 Field Frame 395 Arm 396 Clamp 400 ways 410 blocks 420 blocks 500 ways 510 blocks 520 blocks

Claims

1. A method (400) for assembling a generator rotor (317) carrying permanent magnets (325) and a generator stator (307), comprising the steps of: moving (410) at least one of the generator rotor (317) and the generator stator (307) towards the other of the generator rotor (317) and the generator stator (307); simultaneously energizing (420) the armature (310) of the stator (307) such that a current circulating along the armature generates a magnetic field in a direction opposite to the magnetic field generated by the permanent magnets (325) while at least one of the generator rotor (317) and the generator stator (307) is moving toward the generator rotor (317) and the generator stator (307); The method (400).

2. The method (400) of claim 1, wherein positive and negative DC currents are supplied to the armature (310).

3. The method (400) of claim 1, wherein a frame (380, 390) moves at least one of the generator rotor (317) and the generator stator (307).

4. The method (400) of claim 1, wherein a portion of the armature (310) is powered independently from another portion of the armature (310).

5. determining a distance (370) between the generator rotor (317) and the generator stator (307) at one or more locations; energizing the armature (310) based at least in part on the determined distance (370); and The method of claim 1 , further comprising:

6. The method (400) of claim 1, wherein the at least one of the generator rotor (317) and the generator stator (307) is moved in a vertical direction (350).

7. determining a torque exerted on at least one of the generator rotor (317) and the generator stator (307); energizing the armature (310) based at least in part on the determined torque; The method of claim 1 , further comprising:

8. an armature (310) having a plurality of coils (315); a power source (330) and a control system (335) configured to selectively supply the plurality of coils (315) such that, during assembly of the permanent magnet electric machine, when one of a field (320) comprising one or more permanent magnets (325) and the armature (310) approaches the other of the field (320) and the armature (310), a current flowing along the armature (310) while the field (320) and the armature (310) are approaching each other, generates a magnetic field in a direction opposite to the magnetic field generated by the permanent magnets (325); An armature assembly (300).

9. 10. The armature assembly (300) of claim 8, further comprising one or more sensors (340) configured to determine a distance (370) between the armature (310) and the field (320) at one or more locations.

10. The armature assembly (300) of claim 8, further comprising one or more sensors (345) configured to determine a torque exerted on one of the field (320) and the armature (310).

11. The armature assembly (300) of claim 8, further comprising an armature frame (380) configured to hold the armature (310).

12. The armature assembly (300) of claim 11, wherein the armature frame (380) is configured to move the armature (310) toward the field (320).

13. The armature assembly (300) of claim 8, further comprising a field frame (390) configured to hold a field (320) of the permanent magnets (325).

14. The armature assembly (300) of claim 13, wherein the field frame (390) is configured to move the field (320) toward the armature (310).

15. The armature assembly (300) of claim 8, wherein the permanent magnet electric machine is a generator, and more particularly a wind turbine generator (42) for a direct drive wind turbine.

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