Methods for producing rotors including co-curing and appropriate magnetization.

Abstract

The technology described herein provides rotors and methods for manufacturing rotors. In an embodiment, the method of manufacturing a rotor includes: forming a magnet array by assembling a plurality of magnets into a magnet array, providing a prepreg adjacent to the magnet array, co-curing the magnet array with the prepreg, and magnetizing the magnet array after forming the magnet array.

Description

[0001] This application is a divisional application. The parent application is entitled "Method for producing rotors including co-curing and magnetization at appropriate locations", filed on November 16, 2017, with application number 201780075040.4. Background Technology

[0002] Magnets are useful for a wide variety of applications, such as magnetic arrays in electric rotors and motors. One type of motor, for example, is the surface permanent magnet motor, where the rotor is formed by an array of alternating pole magnets, or a Halbach array. Ideally, the magnetic array has a concentrated magnetic field on one side of the array and essentially no magnetic field on the other side. However, current magnetic arrays cannot shape the magnetic field in this way. Coils are mounted on a stator assembly adjacent to the rotor. A sinusoidal field is generated from the coils and interacts with the sinusoidal magnetic field from the magnetic array to induce magnetic levitation. Currently, the manufacture of the magnetic array, rotor, and motor is complex and expensive, and the rotor can be inefficient and does not always perform as desired. Attached Figure Description

[0003] Various embodiments of the invention are disclosed in the following detailed description and accompanying drawings.

[0004] Figure 1 This is a flowchart illustrating an embodiment of the process used to manufacture a rotor.

[0005] Figure 2A This is a diagram illustrating an embodiment of a magnet array assembly.

[0006] Figure 2B This is a diagram illustrating an embodiment of a magnet array assembly.

[0007] Figure 3A This is a diagram illustrating an embodiment of the magnetization fixing device.

[0008] Figure 3B This is a diagram illustrating an embodiment of the magnetization fixing device.

[0009] Figure 3C This is a diagram illustrating an embodiment of the magnetization fixing device.

[0010] Figure 4A This is a diagram illustrating an embodiment of a magnet array having a magnetization fixing device.

[0011] Figure 4B This is a diagram illustrating an embodiment of a magnet array having a magnetization fixing device.

[0012] Figure 5 This is a diagram illustrating the magnetic field generated by the magnetizing fixing device in a portion of the magnet array according to an embodiment.

[0013] Figure 6 This is a diagram of the magnetic field in the magnet array according to an embodiment.

[0014] Figure 7A This is an illustration of an embodiment of an electric motor, the operation of which is facilitated by a rotor as described herein.

[0015] Figure 7B This is an exploded cross-sectional view of the rotor.

[0016] Figure 8A This is an illustration of an embodiment of an electric motor, the operation of which is facilitated by a rotor as described herein.

[0017] Figure 8B yes Figure 7A and 7B A cross-sectional view of the assembled electric motor.

[0018] Figure 9 This is a diagram of the magnetic field in an electric motor according to an embodiment.

[0019] Figure 10 This is an illustration of an aircraft employing a rotor. Detailed Implementation

[0020] This invention can be implemented in numerous ways, including as a process; an apparatus; a system; a component of matter; a computer program product embodied on a computer-readable storage medium; and / or a processor, such as a processor configured to execute instructions stored on and / or provided by memory coupled to the processor. In this specification, these implementations or any other forms in which the invention may take may be referred to as techniques. Generally, the order of steps of the disclosed process can be varied within the scope of this invention. Unless otherwise stated, a component described as being configured to perform a task, such as a processor or memory, can be implemented as: a general-purpose component temporarily configured to perform the task at a given time; or a special-purpose component manufactured to perform the task. As used herein, the term "processor" refers to one or more devices, circuits, and / or processing cores configured to process data (such as computer program instructions).

[0021] The principles of the invention are illustrated below. Figure 1This document provides a detailed description of one or more embodiments of the invention. The invention is described in conjunction with such embodiments, but is not limited to any particular embodiment. The scope of the invention is limited only by the claims, and the invention encompasses numerous alternatives, modifications, and equivalents. Numerous specific details are set forth in the following description to provide a thorough understanding of the invention. These details are provided for illustrative purposes, and the invention may be practiced without some or all of these specific details. For clarity, technical materials known in the art related to the invention have not been described in detail so as not to unnecessarily obscure the invention.

[0022] In rotor manufacturing, a trade-off is often made between manufacturing complexity (e.g., cost) and performance. The techniques disclosed herein address this trade-off by achieving high performance at a lower cost and with less complexity compared to typical rotor production. Rotors with improved performance compared to typical current rotors are also disclosed herein.

[0023] In one embodiment, the method of manufacturing the rotor includes: forming a magnet array by assembling a plurality of magnets into a magnet array, providing a fabric and an adhesive resin adjacent to the magnet array, co-curing the resin with the magnet array and the fabric, and magnetizing the magnet array after it has been formed.

[0024] In various embodiments, the fabric and adhesive resin are prepregs. For example, a prepreg refers to a fabric having a resin impregnated therein during a “B-stage”. The fabric can be a wide variety of textiles (e.g., various cloths, nonwovens, unidirectional fibers, etc.). In the B-stage, the resin has partially cured, making the fabric gel-like (rather than a liquid state prior to partial curing). Some B-stage fabrics are stored at temperatures below room temperature, causing curing to pause. When the B-stage fabric is brought to room temperature or another temperature threshold, the B-stage fabric continues to cure and eventually fully cures. The resin used for the prepreg fabric can be selected from a wide variety of epoxy resins or other resin systems such as bismaleimide (BMI). In various embodiments, the fabric and adhesive resin are adapted to a high-pressure resin transfer molding process.

[0025] Conventional manufacturing of magnet arrays involves arranging magnetized magnets in an arrangement such as a Halbach array. Because the magnetized magnets are tilted to move and cluster together, this arrangement is aided by a plate. This plate contains grooves to hold the magnets in place until they are bonded to a magnet carrier. The magnets are bonded to the carrier by heating to cure an adhesive material (e.g., epoxy resin). Once bonding is complete, the plate is removed. This process has several drawbacks. First, the plate limits automation in the manufacturing process because it is bulky and incompatible with most robotic arms. Second, the magnet carrier is expensive and heavy. Third, magnets lose strength when heated above a threshold temperature (typically around 80 degrees Celsius). However, in typical bonding steps, epoxy resin requires temperatures exceeding 80 degrees Celsius. This results in a reduction in the strength of the magnet array. Furthermore, the metal carrier adds to the weight of the magnet array, which can affect the mechanical devices that provide the array within it. For example, aircraft using such magnet arrays may consume more fuel.

[0026] A technique for producing rotors, including co-curing and appropriate magnetization, is disclosed. The technique disclosed herein provides an alternative to a typical method that utilizes magnetized magnets and / or magnetized thermomagnets to assemble magnet arrays. In one aspect, the magnets are assembled in an unmagnetized state. Because the magnets can be magnetized after a heating stage, this advantageously prevents loss of magnet strength, which would otherwise be caused by the heating stage. On the other hand, weight and cost are reduced because a magnet carrier is no longer required. Alternatively, the magnets can be co-cured in a glass fiber, polyaryl polyamide fiber, and / or carbon fiber composite structure. Typically, glass fiber and carbon composite structures are lighter and less expensive than the metallic materials used to produce the magnet carrier.

[0027] In various embodiments, the magnet array is generated during a co-curing process, in which unmagnetized magnets are co-cured into the composite structure. The co-cured magnet array is then magnetized at appropriate locations. The magnets used in the magnet array can be of any type, including conventional alternating pole magnets, Halbach array magnets, and multipole magnets such as tripole magnets.

[0028] Figure 1 This is a flowchart illustrating an embodiment of a process for manufacturing a rotor. For example, the process can produce a rotor, such as... Figure 7A and 7B Rotor 704.

[0029] At position 102, the magnets are assembled into an array together with the prepreg. Figure 2A and 2BAn example of a magnet assembly is shown. The magnets can be arranged in an array of any shape, including a circular array. Unlike typical techniques, here the magnets can be blanks at this stage (102) and then magnetized in place (106).

[0030] At 104, the magnet array is co-cured with a fabric (e.g., the prepreg at 102). In various embodiments, co-curing involves heating the fabric to cause it to expand. In some embodiments, heating is performed at a temperature sufficient to fully cure the fabric. For example, co-curing causes pressure and excessive resin exudation, resulting in a rotor with a low resin content. Co-curing can be performed at a variety of temperatures, including those exceeding 80 degrees Celsius. As non-limiting examples, the fabric includes glass fibers, polyaryl polyamide fibers, and / or carbon fibers, etc.

[0031] In various embodiments, the co-curing process utilizes a high-pressure resin transfer molding process (“HP-RTM”). In HP-RTM, the fabric and magnet are dried and assembled in a heated mold (e.g., without resin). For example, resin is injected into the mold in a manner similar to typical plastic injection molding. High pressure is used to infuse the fabric and magnet with resin. Due to the high temperature, the part can cure very quickly (e.g., 90 to 150 seconds). Assembly of the fabric and magnet, including the removal of the completed part, can be performed by a robot. The entire cycle time can range from approximately 2 minutes to approximately 5 minutes. In some cases, not only is the cycle time of HP-RTM less than that of using prepreg, but the raw materials used in HP-RTM are also less expensive.

[0032] At position 106, the magnet array is magnetized. For example, once the magnets have been arranged in the desired configuration, magnetization can be performed at the appropriate location. Magnetization induces a sufficiently strong magnetic field through the grains of the blank constituting the magnet array, causing the magnets in the array to become permanent magnets. Figures 3A-3C Various views of example magnetization fixtures that can be attached to a magnet array to magnetize the magnet array are shown. Figure 4A and 4B A view of an example magnet array with attached magnetization fixing devices is shown.

[0033] Figure 2A This is a diagram illustrating an embodiment of a magnet array assembly. Figure 2A This is an exploded view of an assembly that can be co-cured to produce a magnet array. The assembly includes: an upper fabric skin 202, at least one ring guide 204.1 and 204.2, a plurality of magnets 206, and a lower fabric skin 208.

[0034] The upper fabric skin 202 may include a prepreg, such as a composite fiber pre-impregnated with a matrix material. In some embodiments, the upper fabric skin may be partially cured. For example, in the stage shown at 202, the upper fabric is flexible and stretchable, which facilitates positioning relative to the magnet array. The upper fabric skin is fully cured when the magnet array assembly is fully assembled. For example, the upper fabric skin may include glass fiber, carbon fiber, Kevlar fiber, etc.

[0035] At least one ring guide 204.1 and 204.2 can hold multiple magnets 206 in place. For example, as shown, the ring can be circular to create a circular array. Other sizes and shapes are also possible. Typical techniques where the magnets are magnetized at this stage require heavy and expensive magnet carriers. In contrast, at least one ring guide 204.1 can be made of fibers such as unidirectional fibers (e.g., glass fiber, carbon fiber, etc.). This can lead to cost and weight savings, thereby reducing production complexity and improving the performance of the magnet array and the mechanical devices in which the magnet array is used. As shown, the at least one ring can be triangular to facilitate stability and prevent unwanted movement during the production process.

[0036] The plurality of magnets 206 may comprise any type of magnet. For example, at least one magnet in the magnet array may be a conventional alternating pole magnet, a magnet typically used in Halbach arrays, or a multipole magnet such as a tripole magnet. As shown, the plurality of magnets may be arranged in a ring array. In various embodiments, Figure 2A and 2B The magnet shown is a billet. For example, the billet is not magnetized, but can be magnetized in the appropriate location. For example, the billet can be magnetized by a magnetization fixing device, such as... Figures 3A-3C The fixing device shown.

[0037] The lower fabric skin 208 can be achieved using a prepreg. Unless otherwise described herein, the lower fabric skin 208 can have the same properties as the upper fabric skin 202. For example, the upper skin prevents the magnet from detaching from the lower skin. The lower skin can be part of the remainder of a next higher assembly, such as an electric motor, a lift fan, etc. The configuration of the lower skin can accommodate the loads expected to be seen by the next higher assembly during operation. For example, to prevent friction between the rotor and stator, the fabric used for the upper skin is not an electrical conductor (e.g., glass fiber or polyaryl polyamide fiber). The lower skin can include a fabric with high stiffness, such as carbon fiber. In some embodiments, the co-cured magnet assembly is secondary-bonded to the next higher assembly.

[0038] Figure 2B This is a diagram illustrating an embodiment of a magnet array assembly. Figure 2B This is an isometric cross-sectional view of an assembly that can be co-cured to produce a magnet array. The upper fabric is depicted as a semi-transparent fabric to show the interior of the assembly. The upper fabric can be of any color and have any level of opacity.

[0039] Figure 3A This is an illustration of an embodiment of a magnetizing fixing device. The magnetizing fixing device imparts magnetization with a desired orientation by inducing a sufficiently strong magnetic field in the material. In various embodiments, the magnetizing fixing device is capable of magnetizing multiple magnets simultaneously. The magnetizing fixing device shown here includes: a cooling plate 302, an electromagnet winding 304, and a frame 306.

[0040] Cooling plate 302 is adapted to cool electromagnetic winding 304. In various embodiments, the cooling plate has at least one channel 303 for coolant fluid flow. For example, the cooling plate cools the electromagnetic winding between each magnetization pulse. Coolant fluid can be pumped through at least one channel between each magnetization pulse to cool the magnetized fixing device.

[0041] The electromagnet winding 304 is adapted to generate a magnetic field. The electromagnet winding can be implemented using a coil that is energized to create the magnetic field. For example, a current pulse is propagated through the electromagnet winding. The intensity and timing of the pulse can be predetermined and adjustable. For example, the pulse can have a suitable intensity to generate a magnetic field, thereby creating a permanent magnet. For example, the pulse is between approximately 5,000 amperes and 50,000 amperes. The pulse can last from approximately 0.5 microseconds to 20 microseconds. In various embodiments, the electromagnet winding is energized by a magnetizer (not shown), such as a set of capacitors discharged through a magnetized fixing device.

[0042] Frame 306 is adapted to hold the components of the magnetization fixing device in place. In various embodiments, the frame holds the electromagnet winding 304 and the cooling plate 302 together. The frame may provide alignment holes to facilitate alignment of the magnetization fixing device components. The frame may include mounting features to allow the magnetization fixing device to be coupled to a magnet or array of magnets being magnetized. An example of a magnet array with attached magnetization fixing devices is shown in... Figure 4A and 4B As shown in the image.

[0043] Figure 3B This is a diagram illustrating an embodiment of the magnetization fixing device. Figure 3B yes Figure 3A An assembly view of the magnetization fixing device. As shown, the electromagnetic winding 304 is provided inside the frame, and the cooling plate is provided on the frame.

[0044] Figure 3CThis is a diagram illustrating an embodiment of the magnetization fixing device. Figure 3C yes Figure 3A A cross-sectional view of the magnetization fixing device. As shown, the electromagnetic winding 304 is provided inside the frame, and the cooling plate is provided on the frame.

[0045] Figure 4A This is an illustration of an embodiment of a magnet array having a magnetization fixing device. For example, the magnets in the magnet array 420 can be magnetized in place by the magnetization fixing device 430. Figure 2A and 2B An example of a magnet array is shown in the image. Figures 3A-3C An example of a magnetization fixing device is shown. As shown, the magnetization fixing device may include: a frame 436, an electromagnet winding 434, and a cooling plate 432. The magnetization fixing device can be detachably attached to the magnet array via a mounting member 440.

[0046] Figure 4B This is a diagram illustrating an embodiment of a magnet array having a magnetization fixing device. Figure 4B This is a cross-sectional view of a magnet array with a magnetization fixing device. A magnet array 420 fabric 428 surrounds at least one ring guide 424 and a plurality of magnets 426. As shown, a magnetization fixing device 430 is positioned on the magnet array, wherein an electromagnetic winding is aligned with region A of the plurality of magnets 426.

[0047] In operation, the magnetizing fixture can be moved to a desired region (A) and excited to generate a magnetic field and magnetize the magnets within the desired region. Magnetization can be completed during one or more pulses, wherein the intensity and timing of the pulses are predetermined, as further described herein. Between pulses, a cooling plate 432 can cool the magnetizing fixture. After magnetization of the magnets in region A is completed, the magnetizing fixture can be moved to another region to magnetize the magnets in that region. For example, the magnetizing fixture can be moved along a circular array to magnetize the array of magnets. In this way, after the magnets have been arranged in a desired configuration, the array of magnets can be magnetized in place.

[0048] In some embodiments, Figure 4A and 4B The magnet array shown magnetizes a single pole pair at a time. The magnet array can be indexed to magnetize all pole pairs (e.g., 77 in some instances). In some embodiments, the magnet array is configured to magnetize multiple pole pairs simultaneously.

[0049] Figure 5 This is a diagram illustrating the magnetic field generated by the magnetizing fixing device in a portion of a magnet array according to an embodiment. The diagram shows the electromagnetic winding 534 at the location of the magnetizing fixing device above a plurality of magnets 526. Each magnet in the magnet array is indicated by a dashed box.

[0050] In this example, the magnetizing fixture magnetizes the tripolar magnet along the illustrated axis. The magnetizing fixture magnetizes the magnet (526.2) directly below it, as well as half of each adjacent magnet (526.1 and 526.3). The magnetized area is shown as region "A". In some embodiments (not shown), it is possible to magnetize more magnets simultaneously. In some embodiments, the magnetizing fixture is adapted to magnetize all magnets in the magnet array.

[0051] In one aspect, the component of the magnetic flux generated by the magnetizing fixation device, aligned with the magnetization direction of the grains in the magnet, is effective when the magnetic flux at each point within the magnet meets a threshold level. In some embodiments, the magnetic flux at each point within the magnet exceeds approximately 10 to 30 kOe. If the magnetizing fixation device comprises a ferromagnetic material, the magnetic flux within that material may be relatively high. This level of magnetic flux would saturate all the ferromagnetic material. Therefore, in various embodiments, the magnetizing fixation device adapted to this level of magnetic flux does not include a ferromagnetic material.

[0052] Figure 6 This is a diagram illustrating the magnetic field in a magnet array according to an embodiment. Each magnet in the magnet array 626 is represented by a dashed box. In the example shown, essentially all the magnetic field is on the top side of array 626, and a negligible portion of the magnetic field is on the bottom side of the array. This type of magnetic field may be desirable in various applications where directional magnetic fields are preferred. For example, a magnet array with this pattern of magnetic field can replace a Halbach array. In this example, two pole pairs are shown. Pole pairs can be a large number (e.g., 77) of the complete magnet array. It can be determined according to... Figure 1 The process involves a magnetizing fixing device that generates the magnetic field in the magnet array 526, such as a magnetizing fixing device. Figures 3A-3C A magnetization fixing device. For example, it can be based on... Figure 4A and 4B A magnetic field is generated by magnetization.

[0053] Figure 7A This is an illustration of an embodiment of an electric motor, the operation of which is facilitated by a rotor as described herein. Figure 7A This is an exploded view of the electric motor; Figure 7B This is an exploded cross-sectional view of the rotor. The rotor includes: an upper rotor housing 702, an upper magnet array 704, a stator 706, a lower magnet array 708, a lower rotor housing 712, and multiple bearings 710.

[0054] The upper rotor housing 702 and the lower rotor housing chamber 712 respectively house the upper and lower rotors. In this example, the rotors are implemented by magnetic arrays described herein. An example upper rotor housing is shown with an output shaft on top. The upper magnet array 704 can be positioned such that substantially all of its magnetic field faces downwards. The lower magnet array 708 can be positioned such that substantially all of its magnetic field faces upwards. The stator 706 may include wirewinding mounted to the stator housing. For example, the stator may include a three-phase stranded wire winding mounted to the stator housing. Multiple bearings 710 control the movement between the upper rotor and the stator, and between the lower rotor and the stator.

[0055] Figure 8A This is an illustration of an embodiment of an electric motor, the operation of which is facilitated by a rotor as described herein. Figure 8A This is a cross-sectional view of the assembled electric motor. Figure 8B yes Figure 7A and 7B A cross-sectional view of the assembled electric motor. The electric motor includes: rotor housing 802, upper rotor 804, lower rotor 808, stator housing 807, and stator 806.

[0056] Figure 9 This is a diagram illustrating the magnetic field in an electric motor according to an embodiment. The motor includes a top magnet array 904 and a bottom magnet array 908. As shown, substantially all of the magnetic field of magnet array 904 faces downwards, while the vast majority of the magnetic field of magnet array 908 faces upwards. Therefore, the majority of the field is located in the region between the two arrays, for example, where the stranded windings of the stator are located. Outside this region, a negligible field exists, where energy is wasted. Therefore, Figure 9 This demonstrates the increased efficiency of motors using the rotors disclosed herein compared to typical magnets or magnet arrays.

[0057] Figure 10 This is an illustration of an aircraft employing a rotor. Figure 10 The aircraft shown is a multi-rotor aircraft with an angled rotor 1008. The angled rotor can be implemented using the rotors disclosed herein. For example, the rotor can be... Figure 7A and 7BThe electric motor described herein is used to achieve this. In various embodiments, multirotor aircraft as disclosed herein include a plurality of lifting fans or other rotors configured such that they surround the fuselage and / or other centrally located structures of the aircraft. In some embodiments, a first subset of the rotors may be disposed on one side of the aircraft, and a second subset of the rotors may be disposed on the opposite side of the aircraft. In various embodiments, the corresponding angles of at least a subset of the rotors mounted thereon can be determined at least in part to provide the ability to generate lateral force components in the horizontal plane of the aircraft at the rotor mounting location (which is offset from the center of gravity of the aircraft in the horizontal plane), so as to provide the ability to control the yaw (i.e., rotation about the vertical axis of the aircraft) of the aircraft by applying a torque about the vertical axis.

[0058] The techniques disclosed herein reduce manufacturing complexity by reducing cost and weight. In one aspect, the rotors described herein do not require a conventional magnet carrier. Instead, in various embodiments, the rotors described herein use prepregs such as glass fiber and / or carbon composites, which are lighter than magnet carriers currently typically used. In another aspect, the rotors described herein are lighter and thinner due to, among other things, the use of glass fiber and / or carbon composites.

[0059] Furthermore, the rotors described herein and the techniques used to produce them use fewer types of magnets than typical current magnet arrays. In some embodiments, the number of magnets used to form the array is half the number required for conventional magnet arrays. For example, instead of 308 magnets per array, 154 magnets are used per array, with each magnet being approximately twice the width. In various embodiments, the array comprises M=2, which is the same as the alternating poles, or half the number of magnets in a typical four-magnet array of each cyclic Halbach array. Moreover, the magnet arrays described herein can use fewer individual types of magnets compared to the types of magnets used to form typical current Halbach arrays. In some magnet arrays, two sinterd blanks are used to generate three different types of trapezoidal magnets: one magnetized upwards, one magnetized downwards, and one magnetized laterally. Here, only one sintered blank is available that can generate two different desired types of magnets.

[0060] In various embodiments, for the same magnet mass, the motors described herein have a stronger field in the air gap of the motor than current typical motors (such as those made using M=4 Halbach arrays). The techniques described herein are also compatible with a wide variety of co-curing assembly processes and production tools. For example, typical pick-and-place robots (e.g., robotic arms) can be used. In contrast, typical magnet arrays are produced using bulky magnet carriers and guide frames or rings, which are incompatible with most robots.

[0061] While the foregoing embodiments have been described in detail for clarity of understanding, the invention is not limited to the details provided. Many alternative ways of implementing the invention exist. The disclosed embodiments are illustrative and not restrictive.

Claims

1. A system comprising: a magnetization fixture comprising a frame, an electromagnet winding coupled to the frame, and a cooling plate, wherein the electromagnet winding is adapted to generate a magnetic flux to create a permanent magnet, wherein the cooling plate is adapted to cool the electromagnet winding; and an unmagnetized magnet array removably coupled to the magnetization fixture, wherein the magnetization fixture is adapted to simultaneously magnetize at least a portion of the unmagnetized magnet array comprising a plurality of unmagnetized magnets into a plurality of magnetized magnets, wherein the magnetization fixture and the unmagnetized magnet array are configured to move relative to each other such that the magnetization fixture magnetizes an adjacent portion of the magnetization fixture at each relative positioning of the magnetization fixture and the unmagnetized magnet array.

2. The system of claim 1, wherein a component of the magnetic flux generated by the magnetization fixture aligned with a grain magnetization direction in the unmagnetized magnet array is effective when the magnetic flux satisfies a threshold level at each point within the unmagnetized magnet array.

3. The system of claim 1, wherein the unmagnetized magnet array is formed of a plurality of unmagnetized magnets arranged in a circular array.

4. The system of claim 1, further comprising: a mount configured to removably attach the magnetization fixture to the unmagnetized magnet array. a second surface adjacent to the first surface and at least partially orthogonal thereto, and comprising a second magnetic pole having a second magnetic polarity opposite the first magnetic polarity; 5. The system of claim 1, wherein the magnetization fixture magnetizes each of the plurality of unmagnetized magnets into a tri-pole magnet having a first surface comprising a first magnetic pole having a first magnetic polarity. and a third surface adjacent to the first surface at an end opposite the second surface, and comprising a third magnetic pole having the second magnetic polarity.

6. The system of claim 1, wherein the plurality of magnetized magnets are provided in a rotor of an electric vehicle.

7. The system of claim 6, wherein the electric vehicle comprises an electric aircraft.

8. A method for magnetizing an unmagnetized magnet array, the method comprising: removably coupling a magnetization fixture to an unmagnetized magnet array comprising a plurality of unmagnetized magnets; energizing the magnetization fixture to generate a magnetic field; magnetizing a first subset of the plurality of unmagnetized magnets underneath the magnetization fixture into a plurality of permanently magnetized magnets with one or more pulses of the magnetic field generated by the magnetization fixture; completing magnetization of the first subset of the plurality of unmagnetized magnets; moving the magnetization fixture over a second subset of the plurality of unmagnetized magnets; and magnetizing the second subset of the plurality of unmagnetized magnets underneath the magnetization fixture with one or more pulses generated by the magnetization fixture.

9. The method of claim 8, further comprising: adjusting an intensity and timing of the one or more pulses of the magnetization fixture prior to energizing the magnetization fixture.

10. The method of claim 8, further comprising: cooling the magnetization fixture by providing a cooling fluid to a cooling plate coupled to the magnetization fixture between subsequent pulses generated by the magnetization fixture. ​ ​ 11. The method of claim 8, further comprising: arranging the plurality of un-magnetized magnets into a circular configuration; moving the magnetization fixture over the circular configuration to magnetize the plurality of un-magnetized magnets in place, one un-magnetized magnet subset at a time.

12. The method of claim 8, wherein the magnetization fixture is configured to magnetize a single pole pair at a time.

13. The method of claim 8, wherein the magnetization fixture is configured to magnetize all pole pairs of the un-magnetized magnet array at the same time.

14. The method of claim 8, wherein each of the plurality of permanently magnetized magnets is a tri-pole magnet having a first surface comprising a first magnetic pole having a first magnetic polarity. a second surface adjacent to the first surface and at least partially orthogonal thereto, and comprising a second magnetic pole having a second magnetic polarity opposite the first magnetic polarity; and a third surface adjacent to the first surface at an end opposite the second surface, and comprising a third magnetic pole having the second magnetic polarity.

15. The method of claim 8, wherein magnetizing a first subset of the plurality of un-magnetized magnets at the same time comprises: permanently magnetizing half of each of a first un-magnetized magnet directly below the magnetization fixture and an un-magnetized magnet adjacent to the first un-magnetized magnet directly below the magnetization fixture.

16. The method of claim 8, further comprising: forming a rotor comprising at least one magnetized array, the at least one magnetized array comprising the plurality of permanently magnetized magnets; and coupling the rotor to an electrically powered vehicle.

17. The method of claim 16, wherein the electrically powered vehicle comprises an electrically powered aircraft.

18. A magnetization fixture, comprising: a frame; an electromagnet winding coupled to the frame, wherein the electromagnet winding is adapted to generate magnetic flux to create permanent magnets from an array of un-magnetized magnets provided across the electromagnet winding; and a cooling plate coupled to the frame, wherein the cooling plate is adapted to cool the electromagnet winding, wherein a component of the magnetic flux generated by the magnetization fixture aligned with a grain magnetization direction in the array of un-magnetized magnets is effective when a threshold level of magnetic flux is satisfied at each point within the array of un-magnetized magnets.

19. The magnetization fixture of claim 18, wherein the cooling plate is embedded in the frame and the electromagnet winding is coupled to the frame over the cooling plate.

20. The magnetization fixture of claim 18, wherein the cooling plate comprises at least one channel for a coolant fluid to flow through.

21. The magnetization fixture of claim 18, wherein the electromagnet winding comprises an excitation coil, wherein current pulses are propagated through the electromagnet winding according to a predefined and tunable intensity and spacing.

22. The magnetization fixture of claim 18, wherein the magnetic flux comprises a plurality of pulses of tunable intensity and duration.

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