Sub-pair variable gauge winding process and design method

Abstract

The sub-mother layer variable wire gauge winding process and design method is characterized in that: all the parallel wound windings are designed according to the sub-layer winding principle, so that there is zero voltage between the sub-layer windings, and very thin insulation process can be used for insulation, so as to further improve the copper fullness rate, and more layers can be accommodated, and the skin effect is reduced; similarly, the end winding can also be designed as much as possible to separate the sub-mother layer, so that the number of adjacent cross layers of different phase windings of the end winding is greatly reduced, and the safety is improved.

Description

Technical Field

[0001] This invention belongs to the field of electric motor and new energy vehicle design and manufacturing technology. Background Technology

[0002] With the rapid development of the new energy vehicle industry, especially the pure electric vehicle industry, higher demands are being placed on the high-speed performance and high power density of electric motors. As motor speeds increase, higher requirements are being placed on the performance of motors and related components. More stringent requirements are being placed on the high-speed performance NVH of motor rotors, high-speed bearings, and gears, leading to increased costs and the emergence of issues such as safety and failure rates. Flat wire motors can improve slot fill factor and power density, but the current flat wire winding and core structure, as well as the forming and assembly process, result in a large cross-sectional area of ​​flat wire, leading to significant skin effect and proximity effect. Furthermore, they are basically made in a fixed shape, and the basic production process involves slot paper → manufacturing hairpins → inserting hairpins → end ring shaping → end ring welding → star point connection → insulation treatment at the welding point, etc. The process is complex and requires specialized equipment. Winding schemes for flat wire motors include: Hair-pin, i-pin, x-pin, w-pin, etc. W-pin is a continuous wave winding. Its advantages are that there are almost no solder joints in the entire winding except for the current output and input ports. However, it requires the use of open slots for assembly, which increases the cogging torque. For permanent magnet rotors, in order to minimize magnetic leakage and improve the high-speed mechanical performance of the rotor, the design of the magnetic blocking slots in the rotor core structure is very demanding. In order to ensure sufficient safety, it is unavoidable to form a certain magnetic circuit closure, which leads to magnetic leakage and reduces electromechanical conversion efficiency. Another approach is to use a structure with high-strength carbon fiber wound externally, which increases costs and increases the air gap, also affecting its performance. Summary of the Invention

[0003] Based on the following prior and related applications: 202410619722.9 Second-order three-phase end winding process design and manufacturing method 202410643792.8 Design and Manufacturing Method of Second-Order Three-Phase Axial Flux End Winding 202410684267.0 Design and Manufacturing Method of Bidirectional Axial Flux Second-Order Three-Phase End Winding 202410796145.0 Second-order variable-order three-phase end winding process design and manufacturing method 202410815412.4 Design and Manufacturing Method of Two-Way Flux Second-Order Three-Phase End Winding 202410909726.0 Independent forming process and design method for end windings of motor slot windings 202410930855.8 Independent Forming Process and Design Method for End Windings of Slot-Mounted Axial Flux Motor 202410938850.X Motor slot winding end winding independent forming process 202410947555.0 Separate winding forming process and design method for electric motors 202411008099.X Matrix Flat Wire Winding Process Design and Manufacturing Method 202411244382.2 Design and Manufacturing Method of Triangular Arc Slot-Crossing Winding 202411319540.6 Low-loss winding process design and manufacturing method 202411390722.2 Design and Manufacturing Method of Split Low-Loss Winding 202411448081.1 Low-loss circuit board type end circuit process design and manufacturing method 202411553914.0 Design and manufacturing method for mother-daughter layer circuits to reduce skin effect. Based on the aforementioned prior applications, this invention improves upon the specific embodiments of the series of "distributed split winding process design and manufacturing methods" in the prior applications by proposing a "mother-daughter layer winding and variable wire gauge process and design method". Its features include: designing all parallel windings according to the principle of daughter-layer windings, resulting in zero voltage between daughter-layer windings, allowing for insulation using a very thin insulation process to further improve the copper fill factor, while also accommodating more layers and reducing the skin effect; similarly, the end windings can also be designed with mother-daughter layer separation as much as possible, greatly reducing the number of adjacent cross layers between different phase windings of the end windings and improving safety. Variable gauge type: The cross-sectional dimensions of the gauge can have different shapes in different spaces, and the cross-section inside the groove is different from the cross-section at the outer end of the groove, such as: second-order type, third-order type; double short-pitch type, It can have a structure similar to a continuous wave winding, with no solder joints on either side. Due to the ultra-flat wire's parent-child layer and combined variable gauge size structure, that is: the gauge is composed of a straight slot gauge and a continuous wave gauge superimposed. The straight slot gauge is only present in the slot area (it can slightly extend out of the slot to obtain better equal cross-sectional conductivity), while the continuous wave gauge exists both inside and outside the slot. The two overlap in the slot area, and are electrically connected only on both sides of the slot opening to form a parallel electrical connection. The middle area is insulated with an insulating film to reduce the yielding effect. To obtain an equivalent conductive cross-sectional area, the continuous wave gauge becomes very wide in the slot area, that is: its cross-sectional area is equal to The cross-sectional area of ​​the slot area is approximately equal to, greater than, or less than the design principle: if the goal is to reduce resistance and improve efficiency, the total cross-sectional area of ​​the external slot winding is greater than the total cross-sectional area of ​​the related parallel windings inside the slot; if the goal is to reduce cost and size, the external slot area is smaller than the internal slot conductive cross-sectional area; generally, it is equal to or approximately equal to the design principle; different materials can also be used, see prior application) of the straight slot in-slot wire gauge plus the continuous wave wire gauge in the slot area. Note: The straight slot in-slot wire gauge plus the continuous wave wire gauge can be one or more layers combined; the thickness of the flat wire in the end winding area extending out of the slot can be very thin, allowing for cross-slot insertion between end windings of different phases (two-phase or three-phase lines); Since this continuous wave is only a part of the thin flat wire of the combined wire gauge, its continuous wave winding flat wire is very thin and can be easily slid into the stator core slot, ensuring that the slot is still a semi-open slot, unlike the current continuous wave whose slot is an open slot. It achieves a winding process similar to that of a round wire motor, but the overall and end dimensions are significantly shorter than those of a round wire. Because the flat wire is regular and neat, its continuous wave wire gauge can be neatly arranged and slid into the slot. Its axial dimension can be precisely designed so that after winding, it is regular, neat and has a very short axial dimension, as shown in the figure. Note: Continuous wave does not specifically refer to waveform winding; it can be either continuous wave winding or continuous lap winding. To simplify assembly, it can be either a segmented continuous wave winding or a segmented continuous lap winding. Alternatively, it can be a discontinuous structure, similar to the split winding mentioned in the prior applications of this series, where the end winding is separated from the slot winding. It can be a split type at both ends, or a continuous type on one side and a split type on the other. That is, similar to a hairpin flat wire, it is pre-formed, inserted from one side of the iron core, and then connected to the split end winding on the other side for electrical connection. The electrical connection can be achieved by welding or mechanical contact pressure connection.

[0004] It can be a two-order or three-order relationship; see the attached circuit diagram for details. Alternatively, to minimize the number of adjacent interleavings between different phases in the end winding region, multiple sub-layers can be stacked and then divided into two- or three-order relationships. That is, the end windings extending out of the slot for cross-slot connections are also composed of multiple layers. For example, there are 36 layers per phase per slot, and the total number of layers of the end windings extending out of the slot for cross-slot connections is 12. The goal is to combine as many adjacent layers as possible into a parallel winding and parallel electrical connection relationship for transmission. This can reduce the number of layers that need to be insulated at the line voltage and high voltage level, that is, reduce the number of layers with line voltage between adjacent layers of the end winding, reduce the number of high voltage insulation layers, and improve safety. See the attached circuit diagram.

[0005] Meanwhile, a series of configuration schemes based on independent forming of slot windings and end windings were disclosed. The key points include: the end windings are all thin copper strips bent into shape, which can be interwoven to realize cross-slot wiring of different phases. Note: the end windings in this embodiment have the same shape and structure. For ease of description, they are named first-order, second-order, and third-order end windings, which correspond to the electrical connection of slot windings of different phases, respectively. Among them: 1. Iron core (For the sake of simplicity in the attached drawings, only the outline of the iron core is shown. The actual structure is composed of laminated silicon steel sheets. See attached drawing for details.) Figure 7 1. Two lamination orientation structures are shown respectively; 2. In-slot winding (strictly speaking: the structure in this example is no longer a winding structure but a heterogeneous conductive post); 3, 4, and 5 correspond to the first, second, and third order end windings of the inner ring; 6, 7, and 8 correspond to the first, second, and third order end windings of the outer ring; the principle of this structure can also be found in the previous application. As mentioned above: the naming of first-order, second-order, and third-order is only for ease of explanation and to distinguish the definitions from the perspective of spatial termination. The attached diagram shows that each corresponds to a winding of a different phase. In this scheme with three-order spatial misalignment, the busbar thickness of the winding at the end of each phase can only be 1 / 3 or slightly less than 1 / 3 of the busbar thickness of the winding in the slot. See attached diagram. Figure 14 If it is divided into two-order spatial misalignment, then the busbar thickness of the end winding of each phase (note: also a three-phase electrical winding) can be 1 / 2 or slightly less than 1 / 2 of the busbar thickness of the winding in the slot. See Appendix. Figure 13 : All independently separated end windings in the prior application can be pre-formed or independently formed, manufacturing all end windings (including various types such as enameled wire windings and bare copper plate bent plates) into an integrated flat cylindrical end winding module. This module is then installed and mated onto the stator core, just like installing a motor end cover. It ensures that the end windings in the end cover correspond one-to-one with the windings in the slot and that there is a good electrical connection. It also ensures that there are reliable insulation characteristics between them. The electrical connection can be achieved by pressure mating and pressing, or by welding, using processes such as high-current resistance welding, laser welding, electron beam welding, and plasma welding.

[0006] The relevant outlines for this series of applications are listed below: On May 17, 2024, a high- and low-order scheme for the end winding was first proposed. On July 8, 2024, a 1 / 2 thickness concentric arc copper tile scheme and a split winding scheme were first proposed; and on July 11 and 7.12, a winding scheme and related schemes for an axial flux motor based on relevant theories were proposed. On July 15, 2024, a cross-layer oblique arc copper tile scheme was first proposed; it is a wave winding (or a lap winding, see prior application); a circuit board scheme was proposed in the interim period between the two. On November 29, 2024, a scheme for concentric arc copper tiles with a thickness of 1 / 3 was proposed; the winding is lapped.

[0007] The new application filed on November 28, 2025, combines the above-mentioned approach and focuses on the priority application based on November 29, 2024. It is basically divided into two categories, as follows: Category 1: A separate design for cross-layer oblique arc copper tile schemes, where the electrical connection between the slot winding and the end winding can be achieved through pressure butt welding or welding; it is a wave winding (or a lap winding, see prior application); see appendix. Figure 1-6 Appendix Figure 12-15 and appendix Figure 21-26 , including Figure 21 For the appendix Figure 3 A magnified view of the area corresponding to part number 10, attached. Figure 22-26 With appendix Figure 1-6 The principle of the end winding is the same; this is to further clarify its structural and technological principles. Figure 1-6 The corresponding slot winding has 12 layers (see attached reference). Figure 12-15 ); Appendix Figure 22-26 The corresponding slot winding has 4 layers, which allows for a clearer demonstration of its structure. (Attached) Figure 22-26 For details, please refer to the prior application (including its corresponding part number identification description).

[0008] Category Two: Original Works Figures 7-11 The diagram shows a stator winding scheme for a 48-slot, 8-pole, 3-layer motor with a 1 / 3 bidirectional short-pitch, three-stage interleaving design. It utilizes a 1 / 3 thickness, concentric arc-shaped copper tile design within the same layer. Due to the simultaneous crossing of three-phase windings in the end winding area, the end winding thickness is designed to be less than or equal to 1 / 3 of the winding thickness within the slot to facilitate interleaving wiring at the ends. The circuit diagram is attached. Figure 19 , 20 (Pay attention to the key points) Figure 20It has 48 slots and 8 poles, with 2 pole-phase slots. A, B, and C correspond to different line types, representing different phase windings (A corresponds to dashed line, B to dotted line, and C to double-dotted line). The end winding thickness of this scheme is 1 / 3 of the winding thickness in the slot. For an explanation of the thickness relationship diagram, please refer to the attached diagram. Figure 28 The three diagrams (left, middle, and right) represent different phase windings. The thickness inside the slot is three times that outside the slot. In this example, the winding inside the slot is a busbar winding, with each busbar layer composed of three sub-layers. The middle area is insulated from each other to improve the skin effect. The two ends are connected as a whole to ensure a parallel electrical connection, and each end is electrically connected to the end winding along the corresponding sub-layer position shown in the diagram. This connection can be made by mechanical pressure contact or welding. The diagram shows a lap winding. Therefore, the wiring relationships of the end windings at both ends are shown in the appendix. Figure 10 , Figure 11 One end is a concentric arc copper tile structure of the same layer ( Figure 11 The other end is a multi-layer structure ( Figure 10 The two ends of the structure, when combined, form a closed concentric lapped winding circuit, which can be combined with... Figure 7-9 Let's read and analyze.

[0009] Alternatively: Another important implementation of this application: the mother-daughter layer winding and variable wire gauge process and design method, if the thickness offset orientation of the in-slot and end windings is changed in a timely manner, the end winding thickness can be half that of the in-slot winding, achieving a proper interleaved wave winding relationship between the three-phase windings. See Appendix. Figure 16-18 Part number 11 represents the in-slot winding, and part number 12 represents the end winding.

[0010] The application content is illustrated with relevant case studies: The flat busbar scheme can be divided into pre-entry welding and post-entry welding schemes. 1. Before entering the tank, the busbars at both ends are fused and welded together to form a whole. The welding process can be resistance welding. The advantage of pre-entry welding is that it can weld a large number of busbars at once. After that, the busbars with welded ends will be treated the same as the current thick flat busbars. The subsequent processes are basically the same, including: twisting, flaring, cutting flat, welding, coating, etc. The welding can be laser welding. The advantages of welding after slotting are as follows: Since the busbars and sub-busbars are separated before being installed in the stator slots, each sub-busbar is independent, and its thickness is less than the width of the stator slot opening. Therefore, a sliding-in assembly from the narrow slot opening of the stator core can be used. The flat wire can be pre-formed and uniformly pre-formed outside the slot according to the twist-flaring requirements, eliminating the twist-flaring process after the flat wire winding is installed in the slot. After installation, the mutual fusion welding between the busbars and sub-busbars, as well as the welding between adjacent layers of busbars (i.e., the ends of the busbars to be welded), are completed all at once, combining the welding processes. However, this method still has its limitations. While this may reduce production efficiency, from an efficiency standpoint, pre-welding might be more efficient overall, especially with this busbar design. The busbar has fewer layers and, being composed of multiple thin, flat wires, offers better flexibility during twisting. Therefore, pre-welding before placement in the slot, followed by twisting, flattening, and laser welding after placement, might be preferable. However, if dip welding (see prior application) is used, welding after placement is recommended. For most motors, the maximum temperature limit at peak power is below 200 degrees Celsius, so dip welding is feasible. Therefore, uniform welding after placement is suggested. Furthermore, due to limitations on the bending angle of the busbar, an i-pin-like method with welding at both ends is recommended.

[0011] Analysis: The reason why flat wire motor winding structure has become mainstream is that it is indeed a very good structural solution. Therefore, the cross-bracing I-PIN solution of this application is also a good solution (see also the relevant prior applications). Alternatively, a separate winding scheme can be adopted (see relevant prior applications). The end windings can be copper tiles or copper plates, and are electrically connected to the slot-mounted flat wire straight posts by pressure butt welding or welding. Figuratively speaking, the slot-mounted windings can be called copper posts, and the end windings can be called copper tiles, copper discs, copper fan blades, etc. Alternatively, the rotor can be installed first, and then the end windings can be joined and welded together. This scheme is advantageous because the end windings occupy a smaller area than the air gap, which can reduce the length of the end windings. This is especially true for motors with a small number of pole pairs, where the length of the end windings can be significantly reduced.

[0012] Alternatively, the X-PIN approach could be further modified by changing the soldering area to a horizontal butt joint or overlapping parallel butt joint before soldering (see appendix). Figure 27This can increase the overlapping area and welding area; another approach is the "busbar or longitudinal and transverse busbar" scheme disclosed in this related application. While ensuring that the number of busbar series turns in each phase winding meets the motor parameter requirements, it minimizes the number of parallel branches, preferably with a parallel branch count of 1. It also optimizes the skin effect by maximizing the number of sub-layers in each busbar and by rationally adjusting and optimizing the total number of stator slots. Generally speaking, after balancing manufacturability, mechanical strength, reliability, and cost, it maximizes the total number of slots to further reduce the number of busbar layers in each slot. For example, after the above optimization, the number of busbar layers in each slot can be only two, optimizing performance while simplifying the process, reducing manufacturing costs, and improving reliability. Attached Figure Description Figures 1-6 : Stator winding scheme diagram of equidistant third-order 72-slot 12-pole 36-layer continuous wave winding motor Figures 7-11 The stator winding scheme of a 48-slot, 8-pole, 3-mother-layer motor with a 1 / 3 bidirectional short-pitch three-order interleaved design is shown in the figure. In this scheme, the slots contain 3*3=9 layers of conductors. However, each adjacent 3 layers are sub-layers, connected in parallel, with an insulation layer in between to optimize the skin effect (or, each sub-layer can be composed of thinner conductor layers stacked and connected to further reduce the skin effect), forming 3 mother layers. The mother layers are connected in series with a voltage difference, while the sub-layers have zero voltage, allowing for very thin insulation. One-third of each mother layer's sub-layer is connected to the corresponding end winding. Since the end winding thickness is only one-third of that in the corresponding slot, interleaving between different phases across slots is possible. See the attached figure for details. This embodiment is a double short-pitch concentric lap winding structure; the wiring relationship of the end windings on both sides is shown in the attached figure. Figure 7-11 The corresponding overall diagram and enlarged diagram are shown in the image. Figure 12 The diagram shows the corresponding winding layer arrangement and explanation, where: 1. Straight-line slot wire gauge; 2. Continuous wave wire gauge slot portion; 3. Continuous wave wire gauge slot portion - forming the end winding; Figure 13 For a design scheme to reduce the number of line voltage layers in the end windings, please refer to the attached diagram and related text description.

[0013] Figure 14 , 15 For the appendix Figure 1-6 The wiring diagram of this embodiment is not a corresponding wiring diagram. It is borrowed from the drawings of a prior application and is only used to illustrate the wiring principle.

[0014] Figure 16 , 17 18 adopts a continuous wave third-order variation double-order interleaving scheme, wherein: Appendix Figure 18The scheme is a continuous wave with two dragons on the same trajectory and moving in parallel, three-order variation, two-order interlacing. The end thickness is 1 / 2 of the groove thickness and the end axial direction is two rows of parallel parallel lines. Therefore, the axial dimension = 2*2 = 4 times the groove thickness = 12 mm (Note: the groove width is taken as 3 mm, the width of one dragon at the end is 2 times, and the width of two dragons is 2*2 = 4 times. The gap between the two dragons is not considered). Figure 19 Schematic diagram of stator winding connection for a 48-slot, 8-pole, 3-layer motor with a 1 / 3 bidirectional short-pitch, three-order interleaved configuration. Figure 20 : Circuit diagram of double short-pitch third-order winding Figure 21 Regarding the appendix Figure 3 The enlarged view corresponding to the area marked 10 in the attached figure. Figure 22-26 : A structural diagram illustrating the slot winding and end winding of a motor with four slot winding layers (details of this four-layer scheme can also be found in the prior application "2025109758709 Motor Separate Winding Forming Process and Design Method"). Figure 27 : Welding area is a horizontal butt weld or overlapping parallel butt weld scheme illustration diagram Figure 28 Diagram illustrating the relationship between the end winding thickness and the slot winding thickness (1 / 3 of the end winding thickness). Note: Appendix Figure 16-19 For the sake of clarity, the axial overlap area of ​​the end windings has been widened; in reality, the axial overlap of the end windings is real. The connection between the end winding and the slot winding can be made by mechanical pressurization to ensure a reliable electrical connection. A certain pressure can be applied, and external pressure testing methods can be used, such as axial pressure, radial pressure, or welding processes, etc. Radial pressure can be generated by inserting wedge blocks at the stator slot opening to apply pressure to the winding laminations, or by using an external wedge ring scheme, similar to a tensioning connection process. This mechanically wedges the laminations to generate sufficient pressure. To ensure uniform and sufficient pressure and eliminate uneven load, the wedge blocks can be designed as multi-lobed, or even each winding lamination can have its own dedicated wedge block, resulting in more reliable clamping force. Generally, the conductive contact area for electrical connection via physical contact is designed to be much larger than the cross-sectional area of ​​the conductive body. Therefore, pressure-based electrical connection is more effective than welding processes. It does not produce welding defects such as localized burning and oxidation, and it is also beneficial for secondary disassembly and maintenance. The overall resistance may even be lower than that of a non-connected continuous wave winding because the connection area is a conductive overlap and parallel relationship, increasing the conductive area.

[0015] Alternatively, to ensure that the cross-sectional deformation in the transition region from the radially thick area of ​​the slot winding to the radially narrow area of ​​the end winding does not create a resistance bottleneck, the slot winding can be extended to a certain length, extending into a wide area to eliminate the resistance bottleneck. See the attached diagram.

[0016] To ensure that cooling oil can fully enter the end windings, for winding configurations with two or more windings on the same side (such as concentric lap windings with 2 or more pole phase slots, which will generally have a similar appearance of double or triple parallel windings, see relevant prior applications and figures), the isolation insulation layer of the windings can be added to each of their respective surfaces in advance. In this way, the insulation layer in the end area is not a whole, and there are gaps that allow cooling oil to enter. At the same time, the windings can be bound together through the gaps between the separate insulation layers, similar to the binding process of round wire motors, to ensure that even if the adhesive on the insulation tape falls off, it will not creep and cause a short circuit.

[0017] Because it is very thin and flexible, it can adopt a similar assembly process to a circular wire. It can slide in from the stator slot opening, and has a high slot fill factor, good temperature resistance, and short end dimensions.

[0018] Note: To reduce eddy current losses, the inner support ring and outer wedge ring / wedge block of the end winding used for wedge tightening connection should be equipped with corresponding measures to reduce eddy current losses. They can be made of non-magnetic and non-conductive materials, or a process similar to thin lamination of silicon steel can be used. That is, the support ring can be made of multiple layers of very thin metal rings, such as steel, silicon steel, copper, aluminum, etc. The lamination process can be wrapped with a high-strength heat-resistant insulating film or bonded with heat-resistant adhesive. The wedge gap area in contact with the winding can be isolated by adding a pressure-resistant insulating layer. The support ring or wedge block or wedge ring that is far away from the winding after isolation can also be made of metal materials, such as high-strength steel.

[0019] The wedge support ring is made of thin copper sheet and tightly wound with Teflon. It can be wound in the gap area between the support ring and the winding support, or it can be wound with fine enameled wire in the gap area where the support ring does not contact the winding. The outer side is also first wound with Teflon and then with nylon tiles or slot paper before directly installing aluminum or copper wedges and wedge rings. If welding is used, the copper sheets can be welded using processes such as laser welding and brazing. Alternatively, a folding technique with a slit that is two or three times wider can be used. This involves leaving the slit open, maintaining connection on both sides, and folding along the slit area to create a conductive surface on both sides with a layered middle section (insulation is required between adjacent contact surfaces in the middle area). See attached diagram. To ensure the withstand voltage safety of the end windings, the end windings can be flared and moved towards the larger diameter direction to increase the gap between the end windings of different phases, making it easier to adopt safer insulation processes. Example

[0020] 1. The conductive copper sheet is made of multiple layers with a base unit thickness of 0.3 mm, which makes it easy to bend, connect, and weld. Resistance welding and soldering are both easy, and it is easy to insert into the groove, just like a round wire. 2. The copper tile solution (see prior application) can have fewer layers, using a combination of thick and thin layers. If welding is difficult, pressure electrical connection can be used. The thin layer is the copper tile extending out of the groove, controlling the axial dimension to about 9 mm. The end insulation of the copper tile is easier and does not require flaring. Two types can be made.

[0021] 2.2 Using the sloping area of ​​the semi-open slot of the iron core groove for wedging is also a good solution. The strength is sufficient and safe. The tensile strength of the metal is very strong. After the pressure contact installation is completed, potting or sealing can be performed. This solution is called slot pressurization. It uses miniature wedges inserted into the slot to pressurize the conductor lamination.

[0022] The impregnation and waxing process greatly improves efficiency. Only one tooling is needed. Each busbar is wound with two layers of 0.02mm thick material, and finally wrapped with a layer of Teflon before being inserted into the stator slot. This method is the safest, ensuring mechanical strength, wear resistance, corona insulation, and tight winding. The total thickness is 0.1mm + 0.04mm = 0.14mm, which allows for easy insertion into the iron core without loosening. Slight stretching during tight winding can slightly thin the material, making it easier to insert into the slot.

[0023] The iron core is lined with two layers of polyimide or one layer of Teflon, which provides high strength and safety. During the process of sliding into the slot, the parallel straight conductor can be removed first, and then inserted after completion, which will provide more space.

[0024] Alternatively, an ultra-thin silver film with better conductivity and softer texture can be added between the contact surfaces of the pressure electrical connection to facilitate a smooth transition and improve the performance of the pressure electrical connection. Alternatively, the permanent magnet rotor can be a two-layer magnetic steel composite rotor, as described in the previous application, which eliminates magnetic leakage and ensures mechanical safety; the silicon steel between the two layers is mechanically connected by a high-strength, high-magnetic-resistance material. Calculation of shape to reduce skin effect, and calculation of optimal diameter and aspect ratio; Choose copper strip with the lowest resistivity for processing; The key points of this application are: the concept of parent-child layers, which greatly reduces the gap between parallel winding layers, and the flattening allows for cross-slot insertion, solving the cross-slot problem, reducing the skin effect, improving heat dissipation, and enabling surface contact conduction to the enclosure for heat dissipation; it also greatly reduces the number of layers, and the use of double short-pitch windings reduces the current path and concentric windings reduces the bus layer voltage. Furthermore, this approach, with parallel deployment of in-phase lines, also reduces the proximity effect. Summarize: 1. A 1 / 3 bidirectional short-pitch three-order interleaving scheme is adopted (see attached figure). The end thickness is 1 / 3 of the slot thickness, but the end axial direction is a single row of parallel lines, so the axial dimension = 3 times the slot thickness = 9 mm. However, it must be a concentric lap winding with slot-crossing lines. Concentric lap winding is not suitable for current continuous processing and requires welding. It would be perfect if it could be converted into a continuous wave. The advantage of the three-stage thickness reduction scheme is that it facilitates the circulation of adjacent layer circuits on the other side of the bidirectional short-distance circuit. The axial dimension of the shortest side U-shaped side is 9-10 mm, and the axial dimension of the open side = 4+4+9=17 (the first 4 is due to the rotor end plate, and the second 4 is the area where the wedge-tightening pressure ring is located). This is also acceptable, as both reduce the thickness by 10 mm compared to Geely's design. 2. The same-line double-dragon continuous wave three-stage interlacing scheme is adopted. The end thickness is 1 / 3 of the groove and the end axis is double-row parallel. Therefore, the axial dimension = 3 * 2 = 6 times the groove = 18 mm. However, it is a continuous wave, which is suitable for the current process. There is no cross-groove line and no welding is required. 3. A double-dragon continuous wave three-order variant double-order interleaving scheme is adopted. The end thickness is 1 / 2 of the slot thickness, but the end axial direction is double-row parallel, so the axial dimension = 2*2 = 4 times = 12 mm. However, it is a continuous wave, which is suitable for current technology. There are no cross-slot lines and no welding is required. The end thickness is 1 / 2 of the three-order variant double-order continuous wave winding, that is, the end thickness is 1 / 2 of the three-phase continuous wave scheme is realized. See the attached figure.

[0025] If the two dragons were to overlap radially, it would be perfect; if they didn't overlap, assembly would be much easier.

[0026] 4. The earliest patented high and low order interleaving scheme, double ring concentric winding, the thickness is 1 / 2 of the slot, but the end axial direction is double parallel, so the axial dimension = 4 times the slot = 12 mm; but it must be a concentric lap winding, with cross slot lines, which is not suitable for the current continuous processing, requires welding, and is only suitable for 4, 8, and 12 poles, not suitable for 6 and 10 poles. 5. Circuit board designs must be laser welded, butt welded, or pressure welded; pressure welds are divided into axial planar welds and radial arc-face welds.

[0027] 6. Now that there are many layers, a diagonal cross-slot continuous wave scheme can be used. There are only 6 basic units in the slot, and then the arc thickness can be determined. The thickness of the basic unit is determined according to the arc thickness, and that's it! The best solution has almost no solder joints. It can be designed with reference to continuous wave winding.

[0028] More attention should be paid to the line voltage of the end windings, as the voltage difference cannot be controlled. It is actually possible to control it, but it's difficult because the voltage changes over time, with potential maximum and minimum voltage differences. Therefore, at least 0.05mm insulation film should be used between different phases; 0.02mm might also be acceptable, which would be more aesthetically pleasing, ensuring a perfectly flush fit without the need for flaring. The connection of branches can be as follows: if 6 branches in the same slot are connected in series, then branches in adjacent slots can be connected in parallel. If adjacent slots are connected in series, then only 3 branches in the same slot are connected in series, and the rest are connected in parallel. Therefore, the connection principle is: the fewest solder joints, the shortest line, and the lowest adjacent voltage.

[0029] Alternatively, a conductive heat dissipation sleeve can be added to the outside of the end winding, and an aluminum sleeve and expansion component can be pressed tightly in the pressure-binding area to make close contact with the housing, and thermally conductive silicone can be used for installation; at the same time, in order to reduce eddy currents, a similar thin silicon steel sheet stacking scheme can be adopted, and the sheet material can be copper, aluminum, silicon steel, etc. To ensure that all conductors inside the motor are completely insulated from the outside world and air, a final process such as impregnation, vacuum impregnation, potting, or vacuum potting can be adopted. The end windings provide better heat dissipation, allowing the heat to be conducted directly to the enclosure using aluminum blocks. Welding on the other side can be done around the rotor diameter; 72 slots: With 3 pole phase slots, based on the lap winding and double-order (high-low order) (there is a cross-slot line on the other side, but one less layer, so the line length is equivalent), there are long and short pitches, which will definitely exceed the stator air gap. The preferred scheme is 72 slots, and the minimum axial dimension is 3*6=18. Or diagonal slot-equidistant, requires an even number of layers, high interlayer voltage, minimum value 13; looks more aesthetically pleasing, the other side circuit board solution, laser peripheral welding, thinner, exceeds the air gap radius; Alternatively, both sides can use diagonal cross-slots, with one side being integrated into the slot as a whole, and the other side using an arc-shaped wedge pressure conductive scheme. 48 slots: If the number of polar phase slots is 2, then it follows the double short-pitch third order; the other side circuit board solution, laser peripheral welding, is thinner, 5-7 mm, exceeding the air gap radius; it is still safer to use the arc wedge pressure conductive solution, which is safer than welding and has better conductivity; Use the largest possible end cross-section and aluminum conduction heat dissipation to reduce resistance, lower temperature, and reduce skin effect! In summary: Don't worry too much about long-pitch and cross-slot wires, as the actual wire length is about the same. Prioritize concentric lap windings to reduce interlayer voltage. The arc-shaped wedge pressure conductivity solution may be the best solution, and it will also be the best solution for future mass production. It is much better than welding and can even be applied to existing flat wire motors. Yes, the welding end of the existing hairpin flat wire can be pre-formed (similar to my 3D printed parts). Then, half of the flat wire extending from the groove is removed and bent at 90 degrees. The pre-formed end is also bent at 90 degrees and half is removed. The opening can be appropriately widened. After adding pressure-resistant release paper, it is compacted with a wedge ring and then coated and potted with paint! The end size is shorter and the welding process is eliminated, as well as the twisting, cutting, and welding processes. What are the seven major processes? My hairpin flat wire forming technology is simply a matter of stamping and bending copper plates, which can be made extremely compact. By the way, there's no need to bend it 90 degrees to cut it in half; just extrude it directly to 1 / 2 thickness. Both the inside and outside of the groove should be extruded to 1 / 2 thickness. Alternatively, resistance welding can be used, with uniform clamping and one-time resistance welding! The inside of the groove also uses my patented method: stamping and folding. The advantage is using bare copper with a high-temperature resistant insulating layer! Or, after extreme flaring, you don't need to cut it in half for the butt joint. You can also use my extreme flaring solution to greatly reduce the axial dimension of the hair clip, see the 3D printed part! Note: Insulation between sub-layers or even parent layers can also be achieved by coating with insulating varnish. This can be done using the traditional enameled wire coating process for motors, or by impregnation. Alternatively, the conductive areas on both sides of the conductor sheet used for parallel electrical connections can be pre-isolated and protected to ensure that the varnish film does not adhere to the sides during impregnation, thus avoiding a secondary varnish removal process. Or, because such windings do not undergo frequent bending and do not undergo significant mechanical deformation after impregnation, a wider variety of insulating or insulating varnishes can be used, such as temperature-resistant metallic varnishes or other high-temperature resistant coatings or films.

[0030] Note: Some lines on the same plane appearing in the attached diagram are generated by default when converting 3D to 2D and do not represent special shapes. You can refer to the relevant diagrams when reading.

[0031] The above solution is also applicable to axial flux motors.

[0032] This invention improves upon previously filed series of "distributed split winding process design and manufacturing methods" by proposing "a design method for end winding assemblies that can reduce the skin effect." Its features include: the end winding is separate and independent from the slot winding; the end winding is composed of several relatively thin wires or enameled wires connected in parallel to form a large total conductive cross-sectional area to meet the requirements of large current conduction; the electrical connection between the end winding and the slot winding can be achieved through conductive surface pressure contact butt welding or welding. See the attached drawings for details and specific implementation examples. To achieve a conductive surface pressure contact butt joint, the butt joint ends need to be machined into a neat and flat cross-section to ensure excellent conductivity of the butt joint connection. Additionally, the butt joint ends need to be designed to facilitate the application of pressure, or the entire thin, flexible wire should be cured, such as through potting, to ensure a proper butt joint and good conductivity after pressure is applied. Figure 1-3 The images show various schemes, including thin round lines and thin flat lines.

[0033] Generally, parallel thin wires or enameled wires are brazed at the ends, such as the most common soldering or tin-immersion treatment, so that the ends form a parallel electrical connection. Note: If it is an enameled wire, the insulation varnish needs to be removed from its ends. The conductor can be enameled wire or ultra-flat wire, see relevant prior applications, and the bare copper wire (or bare aluminum wire) can be isolated and insulated with a high-temperature resistant insulation layer; Its conductor cross-section can be round or flat, and the enameled wire can be enameled round or enameled flat; If the fine wire has not undergone curing treatment, pressure contact is not ideal. Welding or brazing methods, such as tin soldering or silver soldering, can be used. To ensure high-temperature resistance, hard brazing can be used. The process specifications include: brazing with a filler metal melting point above 450℃ is considered hard brazing. Hard filler metals include copper-based, silver-based, and aluminum-based alloys. Common fluxes include borax, boric acid, fluorides, and chlorides. Heating methods include flame heating, salt bath heating, resistance heating, and high-frequency induction heating. Hard brazed joints have a strength up to 490MPa and are suitable for workpieces subjected to high stress and operating at high temperatures.

[0034] Soft soldering can also be used. The process specifications include: soldering with a filler metal melting point below 450℃ is considered soft soldering. Commonly used filler metals are tin-lead alloys. Commonly used fluxes include rosin and ammonium chloride solution. Commonly used methods include soldering irons and other flame heating.

[0035] Technical Note: Brazing involves heating the brazing filler metal (with a lower melting point than the base metal) and the workpiece together. The filler metal melts (while the workpiece remains unmelted), wetting and filling the gaps between the base metal and the weldment. The filler metal and base metal diffuse into each other, forming a strong bond. Subject Area: Electrical Engineering (First-level Discipline); Thermal Automation, Power Plant Chemistry and Metallurgy (Second-level Disciplines).

[0036] Brazing is a welding method in which both the filler metal and the workpiece are heated to their melting temperatures simultaneously, and the liquid filler metal fills the gaps between the solid workpieces to join the metals. Before brazing, the oxide film and oil on the contact surfaces of the base materials must be removed to allow the capillary action of the filler metal to function properly after it melts, increasing its wettability and capillary flow. Depending on the melting point of the filler metal, brazing is divided into hard brazing and soft brazing. Brazing results in minimal deformation and a smooth, aesthetically pleasing joint, making it suitable for welding precision, complex components composed of different materials, such as honeycomb panels, turbine blades, carbide cutting tools, and printed circuit boards. Before brazing, the workpieces must be meticulously machined and thoroughly cleaned to remove oil and excessively thick oxide films, ensuring a proper fit at the interface. The fit is generally required to be between 0.01 and 0.1 mm. Compared to fusion welding, only the filler metal melts during brazing; unlike pressure welding, no pressure is applied to the workpieces during brazing. The weld formed by brazing is called a braze seam.

[0037] Alternatively, the above scheme can also adopt a similar hairpin flat wire structure, with one end winding and the slot winding connected as a single unit, or with the slot integrally formed or welded outside the slot, and the other end winding and the slot winding connected by pressure contact or post-welding. During welding, the protruding end of the slot winding can also be widened to improve the convenience of welding or docking.

[0038] To ensure mechanical stability, all end windings can be integrally cured and potted after assembly, or cured with ceramic (or a thin layer of high-temperature resistant insulating material such as ceramic, mica, or basalt can be sprayed onto the surface of the end windings; or a uniform high-temperature resistant insulating protective layer can be formed using conventional ceramic-metal surface adhesion processes; or, to ensure good heat dissipation, a discontinuous insulating coating can be used, i.e., supporting and isolating adjacent conductors to achieve insulation), or grouting and curing can be performed using packaging processes similar to integrated circuits, or even using silicate cement for grouting and curing, while considering both heat dissipation and thermal conductivity. See attached diagram. Another assembly and positioning scheme for the end winding is to use an independent aluminum disc carrier frame for the end winding, which is centered and angled with the stator housing. It can be positioned at the keyway on the outer periphery of the corresponding iron core, and then screwed onto the existing end cover by set screws.

[0039] To further refine the design, the radial shape of the busbar conductive cross-section of the in-slot winding can be transformed into a circumferential arc shape. That is, the busbar conductive cross-section of the in-slot winding has a long radial dimension and a short circumferential dimension. A conductor is used to transition the conductive cross-section connecting it to the end winding, transforming it into a conductive cross-section with a short radial dimension and a long circumferential dimension. This helps reduce the space occupied by the end winding, further refining the structure, shortening the conductive path to reduce resistance, reducing material usage, improving efficiency, and lowering costs. Of course, the shape should be changed while maintaining the conductive cross-sectional area as much as possible to ensure an equivalent conductive cross-sectional area. For example... Figure 3 As shown (see enlarged view for details).

[0040] Note: In the scheme of reducing the skin effect by opening gaps between conductors in different layers, the gaps between adjacent layers can be staggered, similar to how brick joints between adjacent layers are staggered when building a wall to ensure the final integrated strength.

[0041] Advantages of separation: The century-old motor manufacturing process has undergone a major transformation, eliminating the need for enameled wire, making rotor assembly easier, eliminating spatial interference, allowing windings to extend beyond the rotor area, simplifying assembly and all processes, eliminating defective products, and enabling the use of matrix windings, regardless of the number of layers; improved temperature resistance, and conductivity can be achieved through pressure; welding is not necessarily better than butt welding, as butt welding involves precision machining, while welding may result in issues such as incomplete or partial welds or defects; good maintainability, high recyclability, and industry advancements; no more damage, even if welding is used; once separated, it means that the process can be diversified, even using photolithography, achieving zero voltage on the same layer, and nanometer-level insulation; To reduce the skin effect and heat dissipation, it can be made thinner and wider, which is the best solution! Patent it immediately; also apply for the process. First, press it into a diagonal seam with the two sides connected, fold it in half, bend it into a circle, and then pot and cure it with the end cap. After removing the connected parts on both sides and processing it into a mirror surface, it can be connected. Alternatively, it can be resistance welded, one-time welded, or high-current welded. Or, the other side can be directly stamped into shape with the winding in the slot in one go, and then welded to the other side, or it can be made into a W-PIN directly.

[0042] This is especially true for axial flux motors, which can be formed by punching the groove and the end in one go and then bending it.

[0043] Axial magnetic flux can be achieved by stamping, stacking, and welding together; or by bending flat wire into a series of circularly wound planar fan shapes, which is the best W-PIN.

[0044] Regarding the aforementioned online applications, especially 202410619722.9; 202410643792.8; 202410684267.0; 202410796145.0; and 202410815412.4, a method can be adopted where subdivided enameled flat wires are pre-assembled into a coarser matrix flat wire group. That is, each original flat wire with a larger cross-section is subdivided into many smaller cross-section micro-flat wire micro-units. After assembly, each micro-unit is densely and compactly combined to improve slot fill factor. These micro-units are then neatly arranged to form a coarse flat wire group. Within the same coarse flat wire group, the micro-units are essentially connected in parallel, similar to the principle of fine enameled wire winding in a circular wire motor, to reduce the skin effect. This structure is simply referred to as a "matrix flat wire winding." See Appendix. Figure 4-5 Among them, part numbers 1 and 3 indicate the outer contour of the matrix flat wire winding; each differential unit of matrix flat wire windings 2 and 4 is insulated from each other; Note: Figure 4 Represents radial flux motor windings. Figure 5 The windings of axial flux motors are described using low-order windings as examples, as detailed in prior applications. Furthermore, since each thick flat wire group is composed of flat wire micro-units, the overall outer contour of the thick flat wire group can be a non-rectangular cross-section. Therefore, the core slot shape can be designed as non-rectangular to further improve the slot fill factor, and can be similar to the core slot shape of a round wire motor, such as... Figure 26-28 As shown, see the earlier application.

[0045] The advantages of "matrix flat wire winding" include reducing the skin effect, greatly increasing the flexibility of the winding, making it easier to bend and shape, causing less damage to the wire, allowing for a larger curvature of bending, and forming a very small bending transition arc, which is conducive to further compaction; in addition, the fine flat wires within the same thick flat wire group are connected in parallel, so the voltage between them is zero, so their insulation film can be very thin, further improving the slot fill factor; Alternatively, the "ultra-flat wire combination method" mentioned multiple times in previous applications can be used; see appendix. Figure 25 Or, see appendix. Figure 24 .

[0046] Alternatively, a coarser flat wire can be formed by combining subdivided flat wire gauges.

[0047] It is more conducive to heat dissipation, and a pre-set cooling channel network can fully immerse the micro-flat wire windings in the coolant environment. An integral potting, casting, or embedded structure can be adopted to form an integrated module with all end windings, increasing the insulation safety level and mechanical safety, improving insulation and heat dissipation, and reducing electromagnetic noise. Alternatively, previous applications can be consulted. The related applications in this series, especially those concerning 202410619722.9; 202410643792.8; 202410684267.0; 202410796145.0; and 202410815412.4, describe structures that are also applicable to split winding designs, such as... Figure 1-3 As shown, where, Figure 1 This represents a single-sided separation, similar to a hairpin flat wire, which is inserted from one side and then joined to the other side; Figure 2 This represents separation on both sides, meaning that the winding in the middle slot is independent, and the windings at both ends are also separate. See: 7.11 Independent forming process and design method for end windings in slots of axial flux motors; 7.12 Independent forming process for end windings in slots of motors; 7.15 Separate winding forming process and design method for motors (newly applied for, application number not yet received). Various welding methods or pressure butt contact electrical connections can be used, or a bare copper plus insulation material solution can be used to improve temperature resistance; Note: This paragraph and its corresponding figures are borrowed from the figures in the previous patent application, and this approach can be used in this application: Appendix Figure 24 , 25 The description refers to further subdividing the winding cross-section to reduce the skin effect; 36 is the subdivided conductor; 37 is the outer conductor, and 37 represents the conductive substrate of the same layer, i.e., the flat wire group concept of this application; or, metal 3D printing, printed circuit, photolithography chip forming and other processes can be adopted, and 35, 38 and 39 are integral conductor blocks, which can realize parallel electrical connection of all conductors in the 36 and 37 regions, where 38 and 39 are integral, which means that the electrical connection cross-sectional area can be bent or expanded, which can increase the electrical connection cross-sectional area, or, the docking space of the end winding can be shifted and dispersed, see the prior application.

[0048] Figure 25 Similar to the previous ultra-flat wire structure, see the prior application; 40, overall outer contour of the ultra-flat wire group; 41, conductor region of the ultra-flat wire; 42, insulation region.

[0049] Figure 28 Similarly, to further subdivide the winding cross section to reduce the skin effect; 45 each pointing region represents different layers or different flat wire groups, and the basic requirement is that different layers have equal resistance characteristics; 46 each pointing region represents different conductors in the same layer, which are in parallel and can have different resistance values.

[0050] Note: This paragraph and its corresponding illustrations are borrowed from the illustrations in the previous patent application, and this design can be used in this application. Appendix Figure 6-9Part numbers 5, 6, 7, 8, and 9 correspond to different axial sections of the motor core and their functions. They are improvements to prior applications (such as: 202410619722.9 Second-order three-phase end winding process design and manufacturing method and related prior applications mentioned above). The magnetic flux density uniformity compensation cores 5 and 8 can improve the problem of uneven magnetic flux density distribution caused by insufficient magnetic yoke space due to the high-order winding clearance slot. Part number 6 is a magnetic shielding material disc, which is a selective function and can be removed. Its purpose is to prevent the formation of spatial magnetic circuits in this area, which would lead to an increase in eddy currents. As shown in the figure, 6 points to 3 types, and any one can be selected during use. 7 is the central main core area; 9 is the filling compensation core, which fully fills the contact gap between the high-order and low-order end windings and the core, so that the magnetic field of the end windings can fully enter the closed main magnetic circuit to participate in excitation, thereby improving the power density and efficiency of the motor. Figure 8 for Figure 7 The corresponding overall assembly drawing can also correspond to the prior application attachment. Figure 9 It is attached Figure 9 Detailed interpretation diagram (see prior application "202410619722.9 Second-order three-phase end winding process design and manufacturing method 5.17") Note: The previous patent application, "Motor Separate Winding Molding Process and Design Method 7.15 (Just filed, application number not yet received)," is attached. Figure 14-19 All of these are optimized designs to enhance conductivity; among them, part number 33 with a narrow gap is designed to reduce the skin effect by subdividing the end winding into several parallel copper plates that are connected in parallel.

[0051] The above solution is applicable to radial flux and axial flux motors; All independently separated end windings in the prior application can be pre-formed or independently formed, manufacturing all end windings (including various types such as enameled wire windings and bare copper plate bent plates) into an integrated flat cylindrical end winding module. This module is then installed and mated onto the stator core, just like installing a motor end cover. It ensures that the end windings in the end cover correspond one-to-one with the windings in the slot and that there is a good electrical connection. It also ensures that there are reliable insulation characteristics between them. The electrical connection can be achieved by pressure mating and pressing, or by welding, using processes such as high-current resistance welding, laser welding, electron beam welding, and plasma welding.

[0052] Including the hairpin winding mentioned in the prior application "Independent forming process of end winding of motor slot winding" in 7.12, after the end winding of the existing hairpin winding is separated, it can also be pre-formed or independently formed, and all hairpin type end windings are manufactured into an integrated end winding flat cylindrical module. It is installed and mated to the stator core like installing motor end cover, and it is ensured that the end winding in the end cover corresponds one-to-one with the slot winding and ensures a good electrical connection relationship, and ensures that there are reliable insulation characteristics between them. The electrical connection method can be pressure mating and pressing contact, or welding method can be used, such as high current resistance welding, laser welding, electron beam welding, plasma welding and other processes.

[0053] Alternatively, all winding modules can be encapsulated into a single cylindrical ingot; alternatively, a heat dissipation and cooling labyrinth channel can be pre-designed inside; or insulating ceramic material can be installed on the surface of the copper tile, which can be distributed in a mesh, rod, or granular form. In short, it can isolate and insulate adjacent copper tiles while allowing coolant to enter the gaps between the copper tiles. The copper tile has a large surface area and excellent heat dissipation. The side of the integrated end winding module that connects with the slot winding can be precision machined to form a precise flat surface or other curved surfaces that match the slot winding, such as a layout annular conical surface, etc. (as shown in the figure). In short, the mating surfaces of the integrated end winding and the slot winding are precision machined, or even paired and precision machined, so that the two can be precisely and accurately mated to achieve good conductivity. They can be mated by pressure contact to conduct electricity, or by welding processes, such as high-current resistance welding, laser welding, electron beam welding, plasma welding, etc.

[0054] Clearly, in this series of solutions, both the end windings and the slot windings can be pre-formed and manufactured. The slot windings can be pre-formed into a single unit before being inserted into the iron core, which can protect the windings and achieve high interlayer density, improving slot fill factor and thermal conductivity. Furthermore, the structure in this application simplifies the slot windings to straight copper rods (commonly known as "copper pillars"), and the end windings to bent copper plates (commonly known as "copper tiles"). This is no longer a traditional winding made of enameled wire. Similar to the previously applied ultra-flat wire series motors, it allows for the separate design and later synthesis of the conductor layer and insulation layer. This enables the insulation layer to be made of various high-temperature resistant materials, or even air isolation, greatly improving the winding's heat resistance, increasing slot fill factor and winding yield, while reducing process difficulty and cost. See previous applications; Ensure that the inductance of each phase is identical to eliminate circulating current. The above design method applies to relevant prior applications, especially to patent application schemes 202410619722.9; 202410643792.8; 202410684267.0; 202410796145.0; and 202410815412.4. This principle also applies to axial flux motors; counter-rotating dual rotor motors; and internal and external dual flux types. Axial flux motors can refer to the relevant solutions in the prior application, namely: arranging two or more relatively independent axial flux windings and permanent magnets (or non-permanent magnet current excitation windings) according to the corresponding phase difference angles, and controlling them according to the complementary waveform relationship, can achieve the same effect. Since the axial force of the axial flux motor is very large, it is basically used in the form of double disks or multiple disks to balance the axial force. Moreover, the axial flux motor has the characteristic of short axial dimension. Therefore, it is more advantageous to use the double disk or multiple disk scheme described in this patent application to design a compact high power density motor.

[0055] It can be a single-rotor or dual-rotor motor, as well as a dual-rotor motor with magnetic flux on both sides and a counter-rotating dual-rotor motor. Its electromagnetic wires can be round or flat; the current waveform can be: square wave, square wave + composite wave, or sine wave; Regarding the method of introducing rotor winding current from the outside for dual-rotor motors, please refer to the prior applications (202211030428.1 Dual-rotor motor current dynamic and static physical ports, 202211098410.5 Constant reluctance rotary transformer and core design and manufacturing method) and related solutions below.

[0056] The above solution can also be used for conventional single-rotor motors, such as replacing existing brushless or brushed solutions.

[0057] Note: The above solution applies to all types of electric motors and generators, including asynchronous motors, synchronous motors, brushless motors, brushed motors, induction motors, permanent magnet motors, switched reluctance motors, etc.

[0058] The three-phase lines mentioned above can be the input / output harness terminals of a three-phase motor, a three-phase induction asynchronous motor, a brushless DC motor, or a permanent magnet synchronous motor.

[0059] Alternatively, the dynamic and static port connection method described in this article can also be a sliding brush method, or a sliding carbon brush solution that is easy to replace.

[0060] Note: The terms used for the dynamic and static physical ports in this article are relative and interchangeable in practice. The terms for inner and outer rotors are relative and have interactive mechanical properties, and they can be used interchangeably as inner and outer rotors.

[0061] Note: The part numbering in the attached drawings uses the same numbering for common parts in different drawings, while different numbering is used for related equivalent functional parts in specific drawings. This is entirely to help the instruction manual to more clearly and accurately describe their working principles.

[0062] All design ideas, structures, methods, and theories presented in this document can be used to guide design. The technical content disclosed in its design theories, methods, implementation models, structures, schematic diagrams, structural diagrams, simplified diagrams, mechanism diagrams, and specific embodiments can be used to design and manufacture various types of engine devices. The implementation mechanisms listed in this patent are typical examples; not all specific facility schemes and mechanism types are listed here. Any cross-reorganization, mutual reference, combination, or arrangement of design theories, ideas, methods, models, mechanisms, or components disclosed in this document, as well as various application examples of this technical category, fall within the scope of this intellectual property protection. Any unauthorized use of these principles in design or application constitutes infringement. For example, the relevant design theories and methods are applicable to traditional electric motors, generators, and other similar power sources.

Claims

1. The process and design method of variable wire gauge winding with mother and daughter layers, including motor windings, stator, rotor, and housing, is characterized by: All parallel windings are designed according to the principle of sub-layer windings, so that there is zero voltage between sub-layer windings. Insulation can be carried out with very thin insulation technology to further improve the copper full rate. At the same time, more layers can be accommodated and the skin effect is reduced. Similarly, the end windings can also be designed with parent and child layers separated as much as possible, so that the number of adjacent cross layers of different phase windings of the end windings is greatly reduced, and safety is improved. Variable gauge type: The cross-sectional dimensions of the gauge can have different shapes in different spaces, and the cross-section inside the groove is different from the cross-section at the outer end of the groove, such as: second-order type, third-order type; double short-pitch type, It can have a structure similar to a continuous wave winding, with no solder joints on either side. Due to the super-flat wire's parent-child layer and the combined variable wire gauge size structure, that is: the wire gauge is composed of a straight slot wire gauge and a continuous wave wire gauge. The straight slot wire gauge is only present in the slot area (it can slightly extend out of the slot to obtain a better equal cross-sectional conductivity effect), while the continuous wave wire gauge exists both inside and outside the slot. The two overlap in the slot area and are only electrically connected on both sides of the slot to form a parallel electrical connection. The middle area is insulated with an insulating film to reduce the yielding effect. In order to obtain an equivalent conductive cross-sectional area, the continuous wave wire gauge becomes very wide in the slot area, that is: its cross-sectional area is equal to or approximately equal to or greater than or less than (determined according to design principles: if it is desired to reduce resistance and improve efficiency, the total cross-sectional area of ​​the slot winding is greater than the total cross-sectional area of ​​the related parallel windings inside the slot). If the goal is to reduce costs and size, the conductive cross-sectional area outside the slot should be smaller than that inside the slot. Generally, the design principle of equal or approximately equal to is adopted; different materials can also be used (see prior application) The total cross-section of the slot area of ​​the straight slot wire gauge plus the continuous wave wire gauge. Note: The straight slot wire gauge plus the continuous wave wire gauge can be one or more layers combined; the thickness of the flat wire in the end winding area extending out of the slot can be very thin, and cross-slot insertion between end windings of different phases (two-phase or three-phase lines) can be carried out. Since this continuous wave is only a part of the thin flat wire of the combined wire gauge, its continuous wave winding flat wire is very thin and can be easily slid into the stator core slot, ensuring that the slot is still a semi-open slot, unlike the current continuous wave whose slot is an open slot. It achieves a winding process similar to that of a round wire motor, but the overall and end dimensions are significantly shorter than those of a round wire. Because the flat wire is regular and neat, its continuous wave wire gauge can be neatly arranged and slid into the slot. Its axial dimension can be precisely designed so that after winding, it is regular, neat and has a very short axial dimension, as shown in the figure. Note: Continuous wave does not specifically refer to waveform winding; it can be either continuous wave winding or continuous lap winding. To simplify assembly, it can be either a segmented continuous wave winding or a segmented continuous lap winding. Alternatively, it can be a discontinuous structure, similar to the split winding mentioned in the earlier applications of this series, where the end winding is separated from the slot winding. It can be a split type at both ends, or a continuous type on one side and a split type on the other. That is, similar to a hairpin flat wire, it is pre-formed, inserted from one side of the iron core, and then connected to the split end winding on the other side for electrical connection. The electrical connection can be achieved by welding or mechanical contact pressure connection. It can be a two-order or three-order relationship; see the attached circuit diagram for details. Alternatively, to minimize the number of adjacent interleavings between different phases in the end winding region, multiple sub-layers can be stacked and then divided into two- or three-order relationships. That is, the end windings extending out of the slot for cross-slot connections are also composed of multiple layers. For example, there are 36 layers per phase per slot, and the total number of layers of the end windings extending out of the slot for cross-slot connections is 12. The goal is to combine as many adjacent layers as possible into a parallel winding and parallel electrical connection relationship for stacking and transmission. This can reduce the number of layers that need to be insulated at the line voltage and high voltage level. In other words, it reduces the number of layers with line voltage between adjacent layers of the end winding, reduces the number of high voltage insulation layers, and improves safety. See the attached circuit diagram. Meanwhile, a series of configuration schemes based on independent forming of slot windings and end windings were disclosed. The key points include: the end windings are all thin copper strips bent into shape, which can be interwoven to realize cross-slot wiring of different phases. Note: the end windings in this embodiment have the same shape and structure. For ease of description, they are named first-order, second-order, and third-order end windings, which correspond to the electrical connection of slot windings of different phases, respectively. Wherein:

1. Iron core (for the sake of simplicity, only the outline of the iron core is shown in the attached diagram. The actual structure is composed of silicon steel laminations. See attached diagram 7, which shows two lamination orientations); 2. In-slot winding (strictly speaking, the structure in this example is no longer a winding structure but an anisotropic conductive post); 3, 4, and 5 correspond to the first, second, and third order end windings of the inner ring; 6, 7, and 8 correspond to the first, second, and third order end windings of the outer ring. The principle of this structure can also be found in the previous application. As mentioned above: the naming of first-order, second-order, and third-order is only for ease of explanation and to distinguish the definitions from the perspective of spatial arrangement. The attached diagram can correspond to windings of different phases respectively. In this scheme, which is divided into three-order spatial misalignment, the busbar thickness of the end winding of each phase can only be 1 / 3 or slightly less than 1 / 3 of the busbar thickness of the winding in the slot, see attached diagram 14; if it is divided into two-order spatial misalignment, the busbar thickness of the end winding of each phase (note: also a three-phase electrical winding) can be 1 / 2 or slightly less than 1 / 2 of the busbar thickness of the winding in the slot, see attached diagram 13. All independently separated end windings applied for earlier can be pre-formed or independently formed, manufacturing all end windings (including various types such as enameled wire windings, bare copper plate bending plates, etc.) into an integrated flat cylindrical end winding module, which is installed and mated onto the stator core like installing motor end covers, ensuring that the end windings in the end cover correspond one-to-one with the windings in the slot and ensuring a good electrical connection, and ensuring reliable insulation characteristics between them. The electrical connection can be achieved by pressure mating and pressing contact, or by welding, such as high current resistance welding, laser welding, electron beam welding, plasma welding, etc. The relevant outlines for this series of applications are listed below: On May 17, 2024, a high- and low-order scheme for the end winding was first proposed. On July 8, 2024, a 1 / 2 thickness concentric arc copper tile scheme and a split winding scheme were first proposed; and on July 11 and 7.12, a winding scheme and related schemes for an axial flux motor based on relevant theories were proposed. On July 15, 2024, a cross-layer oblique arc copper tile scheme was first proposed; it is a wave winding (or a lap winding, see prior application); a circuit board scheme was proposed in the interim period between the two. On November 29, 2024, a scheme for concentric arc copper tiles with a thickness of 1 / 3 was proposed; this is a lap winding scheme. The new application filed on November 28, 2025, combines the above-mentioned approach and focuses on the priority application based on November 29, 2024. It is basically divided into two categories, as follows: Category 1: A separate design for cross-layer oblique arc copper tile, where the electrical connection between the slot winding and the end winding can be achieved by pressure butt welding or welding; it is a wave winding (or a lap winding, see prior application); see Figures 1-6; Figures 12-15 and 21-26, where Figure 21 is a partial enlarged view of the area corresponding to part number 10 in Figure 3; Figures 22-26 have the same end winding principle as Figures 1-6, and are used to further clarify its structural and technological principles; Figures 1-6 correspond to 12 layers of slot winding (see Figures 12-15 for reference); Figures 22-26 correspond to 4 layers of slot winding, which can more clearly show its structure; details related to Figures 22-26 can be found in prior applications (including their corresponding part number identification descriptions). Category 2: Original, Figures 7-11: 1 / 3 bidirectional short-pitch three-stage interleaving scheme for 48-slot 8-pole 3-mother-layer motor stator windings, using a 1 / 3 thickness concentric arc copper tile scheme. The end winding area has a problem of three-phase windings simultaneously crossing each other, so the end winding thickness is less than or equal to 1 / 3 of the thickness of the winding in the slot as the design basis to facilitate interleaving wiring at the ends; see attached figures 19 and 20 for circuit diagrams (focus on Figure 20); it is 48 slots 8 poles, with 2 pole-phase slots. A, B, and C correspond to different line types, representing different phase windings (A corresponds to dashed line, B to dotted line, C to double dotted line); the thickness relationship diagram of the end winding thickness being 1 / 3 of the thickness of the winding in the slot can be seen in attached figure 28. The three figures on the left, middle and right represent different phase windings. The thickness inside the slot is three times that outside the slot. In this example, the winding inside the slot is a bus-and-sub-bus winding. Each bus layer is composed of three sub-layers. The middle area is insulated from each other to improve the skin effect. The two ends are connected as one to ensure a parallel electrical connection. Each end is electrically connected to the end winding along the corresponding sub-layer position area shown in the figure. This can be done by mechanical pressure contact or welding. The scheme shown is a lap winding. Therefore, the wiring relationship of the end windings at both ends is shown in Figures 10 and 11. One end is a concentric arc copper tile structure in the same layer (Figure 11), and the other end is a cross-layer structure (Figure 10). The two end structures are combined to form a closed concentric lap winding circuit relationship, which can be read and analyzed in conjunction with Figures 7-9. Alternatively: Another important implementation of this application: the process and design method of the mother-daughter layer winding and variable wire gauge, if the thickness offset orientation of the slot winding and the end winding is changed in time, the thickness of the end winding can be half the thickness of the slot winding to achieve the effect of the three-phase windings being appropriately interleaved. See Figures 16-18, where part number 11 represents the slot winding and 12 represents the end winding. The application content is illustrated with relevant case studies: The flat busbar scheme can be divided into pre-entry welding and post-entry welding schemes.

1. Before entering the tank, the busbars at both ends are fused and welded together to form a whole. The welding process can be resistance welding. The advantage of pre-entry welding is that it can weld a large number of busbars at once. After that, the busbars with welded ends will be treated the same as the current thick flat busbars. The subsequent processes are basically the same, including: twisting, flaring, cutting flat, welding, coating, etc. The welding can be laser welding. The advantages of welding after slotting are as follows: Since the busbars and stator windings are separate before being installed in the stator slots, each busbar is independent and its thickness is less than the width of the stator slot opening. This allows for a sliding-in assembly from the narrow slot opening of the stator core. Therefore, the flat wire can be pre-formed and uniformly pre-formed outside the slot according to the twist-flaring requirements, eliminating the twist-flaring process after the flat wire winding is installed. After installation, the mutual fusion welding between the busbars and stator windings, as well as the welding between adjacent busbar layers (i.e., the ends of the busbars to be welded), are completed all at once, combining the welding processes. However, this method may still reduce production efficiency. From a production efficiency perspective, it might be better to advance the process earlier. The welding method offers higher overall production efficiency, especially when using this busbar design. Since the busbar has fewer layers and is composed of multiple thin, flat wires, it exhibits better flexibility during twisting. Therefore, welding before placement in the slot, followed by twisting, cutting, and laser welding after placement, may be preferable. However, if dip welding (see prior application) is used, welding after placement in the slot is recommended. For most motors, the maximum temperature limit at peak power is within 200 degrees Celsius, so dip welding is feasible. Therefore, uniform welding after placement in the slot is recommended. Additionally, due to the limited bending angle of the busbar, a method similar to an i-pin is recommended, with welding at both ends. Analysis: The reason why flat wire motor winding structure has become mainstream is that it is indeed a very good structural solution. Therefore, the cross-bracing I-PIN solution of this application is also a good solution (see also the relevant prior applications). Alternatively, a separate winding scheme can be adopted (see relevant prior applications). The end windings can be copper tiles or copper plates, and are electrically connected to the slot-mounted flat wire straight posts by pressure butt welding or welding. Figuratively speaking, the slot-mounted windings can be called copper posts, and the end windings can be called copper tiles, copper discs, copper fan blades, etc. In addition, the rotor can be installed first, and then the end windings can be joined and welded together. This scheme is advantageous because the end windings occupy a smaller area than the air gap, which can reduce the length of the end windings. Especially for motors with a small number of pole pairs, the length of the end windings can be significantly reduced. Alternatively, the X-PIN approach can be further modified by changing the welding area to a horizontal butt joint or overlapping parallel butt joint before welding (see Figure 27). This can increase the overlapping area and the welding area. Another approach is the "busbar or longitudinal and transverse busbar" scheme disclosed in this related application. While ensuring that the number of busbar series turns in each phase winding meets the motor parameter requirements, the number of parallel branches should be minimized, preferably with 1 parallel branch. The skin effect can be optimized by maximizing the number of sub-layers in each busbar. The total number of stator slots of the motor can be optimized by reasonably adjusting and optimizing the total number of slots. Generally speaking, after balancing manufacturability, mechanical strength, reliability, and cost, the total number of slots should be maximized to further reduce the number of busbar layers in each slot. For example, after the above optimization, the number of busbar layers in each slot can be only two, which optimizes performance, simplifies the process, reduces manufacturing costs, and improves reliability.

2. The variable gauge winding process and design method for the mother-daughter layer according to claim 1, characterized in that: Equidistant three-order continuous wave winding motor stator winding; Figures 1-6: Equidistant three-order 72-slot 12-pole 36-layer continuous wave winding motor stator winding scheme; Figure 12 is its corresponding winding layer arrangement and explanation diagram, where:

1. Straight-type slot wire gauge; 2. Continuous wave wire gauge slot part; 3. Continuous wave wire gauge slot part - forming the end winding; Figures 7-11: 1 / 3 bidirectional short-pitch three-order interleaved scheme 48-slot 8-pole 3-mother-layer winding motor stator winding scheme diagram, as shown in the figure, this scheme shows 3*3=9 layers of conductors in the slot, however, each adjacent 3 layers are sub-layers, which are parallel windings, with insulation in between. The insulation layer optimizes the skin effect (or each sub-layer can be stacked and connected by thinner conductor layers to further reduce the skin effect), forming a 3-layer mother layer. The mother layers are connected in series with a voltage difference, while the sub-layers have zero voltage, allowing for very thin insulation. In this case, 1 / 3 of the sub-layer of each mother layer is connected to the corresponding end winding. Since the thickness of the end winding is only 1 / 3 of that in the corresponding slot, different phases can be interleaved across slots. See the attached figure for details. This embodiment is a double short-pitch concentric lap winding structure. The wiring relationship of the end windings on both sides is shown in the overall view and enlarged view in Figure 7-11. Figure 13 is a design scheme diagram for reducing the number of line voltage layers in the end winding. Please refer to the attached figure and related text description. Figures 14 and 15 are schematic diagrams illustrating the wiring principle of the embodiments in Figures 1-6, but they are not corresponding wiring diagrams. They are borrowed from the drawings in the prior application and are only used to illustrate the wiring principle. You can refer to these figures. Figures 16, 17, and 18 show the continuous wave three-order variation double-order interlacing scheme. Among them, Figure 18 shows the continuous wave three-order variation double-order interlacing scheme with two dragons on the same trajectory and in parallel. The end thickness is 1 / 2 of the groove and the end axis is two rows of parallel parallel lines. Therefore, the axial dimension = 2*2 = 4 times the groove width = 12 mm (Note: The groove width is taken as 3 mm, the width of one dragon at the end is 2 times, and the width of two dragons is 2*2 = 4 times. The gap between the two dragons is not considered). Figure 19 is a schematic diagram of the stator winding connection of a 48-slot, 8-pole, 3-mother-layer motor with a 1 / 3 bidirectional short-pitch three-order interleaving scheme. Note: Figures 16-19 are for clarity by showing the axial overlap of the end windings; in reality, the end windings overlap axially. The connection between the end winding and the slot winding can be made by mechanical pressurization to ensure a reliable electrical connection. A certain pressure can be applied, and external pressure testing methods can be used, such as axial pressure, radial pressure, or welding processes, etc. Radial pressure can be generated by inserting wedge blocks at the stator slot opening to apply pressure to the winding laminations, or by using an external wedge ring scheme, similar to a tensioning connection process. This mechanical wedge surface generates sufficient pressure. To ensure uniform and sufficient pressure and eliminate uneven load, the wedge blocks can be designed as multi-lobed split types, or even each winding lamination can have its own dedicated wedge block, which can achieve more reliable clamping force. Generally, the design principle is that the conductive contact area for electrical connection through physical contact is designed to be much larger than the cross-sectional area of ​​the conductive body. Therefore, pressure electrical connection is better than welding and other processes. It does not produce welding defects such as local burns and oxidation, and it is also beneficial for secondary disassembly and maintenance. The overall resistance is even lower than that of non-connected continuous wave windings because the docking area has a conductive overlapping parallel relationship, which increases the conductive area. Alternatively, in order to ensure that the cross-sectional deformation of the transition region from the radially thick area of ​​the slot winding to the radially narrow area of ​​the end winding creates a transition resistance bottleneck, the slot winding can be extended to a certain length, extending into a wide area to eliminate the resistance bottleneck; see attached figure. In order to ensure that the cooling oil can fully enter the end windings, for winding configurations with two or more windings on the same side (such as concentric lap windings with 2 or more pole phase slots, which will generally have a similar appearance of double or triple parallel windings, see relevant prior applications and drawings), the isolation insulation layer of the windings can be added to each of their respective surfaces in advance. In this way, the insulation layer in the end area is not a whole, and there are gaps that allow the cooling oil to enter. At the same time, the windings can be bound by the gaps between the separate insulation layers, similar to the binding process of round wire motors, to ensure that even if the adhesive on the backing tape falls off, it will not creep and cause a short circuit. Because it is very thin and flexible, it can adopt a similar assembly process to a circular wire. It can slide in from the stator slot opening, and has a high slot fill factor, good temperature resistance, and short end dimensions. Note: To reduce eddy current losses, the inner support ring and outer wedge ring / wedge block of the end winding used for the wedge tightening connection should be equipped with corresponding measures to reduce eddy current losses. These can be made of non-magnetic and non-conductive materials, or similar thin-layer lamination processes like silicon steel can be used. That is, the support ring can be made of multiple layers of very thin metal rings, such as steel, silicon steel, copper, aluminum, etc. The lamination process can be wrapped with a high-strength, heat-resistant insulating film or bonded with heat-resistant adhesive. A voltage-resistant insulating layer can be added to the wedge gap area in contact with the winding for isolation. The support ring, wedge block, or wedge ring located far from the winding after isolation can also be made of metal materials, such as high-strength steel. The wedge support ring is made of thin copper sheet and tightly wound with Teflon. It can be wound in the gap area between the support ring and the winding support, or it can be wound with fine enameled wire in the gap area where the support ring does not contact the winding. The outer side is also first wound with Teflon and then with nylon tiles or slot paper before directly installing aluminum or copper wedges and wedge rings. If welding is used, the copper sheets can be welded using processes such as laser welding and brazing. Alternatively, a folding technique with a slit that is two or three times wider can be used. This involves leaving the slit open, maintaining connection on both sides, and folding along the slit area to create a conductive surface on both sides with a layered middle section (insulation is required between adjacent contact surfaces in the middle section). See attached diagram. To ensure the withstand voltage safety of the end windings, the end windings can be flared and moved towards the larger diameter direction to increase the gap between the end windings of different phases, making it easier to adopt safer insulation processes.

3. The variable wire gauge winding process and design method of the mother-daughter layer according to claim 1, characterized in that: Example:

1. The conductive copper sheet uses a 0.3 mm base unit thickness for multi-layer stacking, making it easy to bend, connect, and weld. Resistance welding and soldering are both easy, and it is easy to insert into the groove, similar to a round wire; 2. The copper tile solution (see prior application) can have fewer layers, using a combination of thick and thin layers. If welding is difficult, pressure electrical connection can be used. The thin layer is the copper tile extending out of the groove, controlling the axial dimension to about 9 mm. The end insulation of the copper tile is easier and does not require flaring; 2.2 Using the sloping area of ​​the semi-open groove of the iron core groove for wedging is also a good solution. The strength is sufficient and safe, and the tensile strength of the metal is very high. Strong, pressure contact installation can be potted or sealed after installation; this scheme is called slot pressurization, which uses micro wedges inserted into the slot to pressurize the conductor laminations; the impregnation and waxing process greatly improves efficiency, and only one tooling is needed. Each busbar is wound with two layers of 0.02, and finally wrapped with a layer of Teflon before being inserted into the stator slot. This is the safest method, which ensures mechanical strength, wear resistance, corona insulation, and tight winding. The total thickness = 0.1 + 0.04 = 0.14, which can be easily inserted into the iron core and ensures that it does not loosen. When tightly wound, a slight stretching can slightly thin it, making it easier to insert into the slot. The iron core is lined with two layers of polyimide or one layer of Teflon, which provides high strength and safety. During the process of sliding the conductor into the slot, the parallel straight conductor can be removed first, and then inserted after completion, which will provide more space. Alternatively, an ultra-thin silver film with better conductivity and softer texture can be added between the contact surfaces of the pressure electrical connection to facilitate a smooth transition and improve the performance of the pressure electrical connection. Alternatively, the permanent magnet rotor can be a two-layer magnetic steel composite rotor, as described in the previous application, which eliminates magnetic leakage and ensures mechanical safety; the silicon steel between the two layers is mechanically connected by a high-strength, high-magnetic-resistance material. Calculation of shape to reduce skin effect, and calculation of optimal diameter and aspect ratio; Choose copper strip with the lowest resistivity for processing; The key points of this application are: the concept of parent-child layers, which greatly reduces the gap between parallel winding layers, and the flattening allows for cross-slot insertion, solving the cross-slot problem, reducing the skin effect, improving heat dissipation, and enabling surface contact conduction to the enclosure for heat dissipation; it also greatly reduces the number of layers, and the use of double short-pitch windings reduces the current path and concentric windings reduces the bus layer voltage. Furthermore, this approach, with parallel deployment of in-phase lines, also reduces the proximity effect. Summarize:

1. A 1 / 3 bidirectional short-pitch three-stage interleaving scheme is adopted (see attached figure). The end thickness is 1 / 3 of the slot thickness, but the end axial direction is a single row of parallel lines, so the axial dimension = 3 times the slot thickness = 9 mm. However, it must be a concentric lap winding with cross-slot lines. Concentric lap winding is not suitable for the current continuous processing and requires welding. It would be perfect if it could be converted into a continuous wave. The advantage of the three-stage thickness reduction scheme is that it facilitates the circulation of adjacent layer circuits on the other side of the bidirectional short distance. The axial dimension of the shortest side U-shaped side is 9-10 mm, and the axial dimension of the open side = 4+4+9 = 17 (the first 4 is due to the rotor end plate, and the second 4 is the area where the wedge-tightening pressure ring is located). This is also acceptable, both of which reduce the thickness by 10 mm compared to Geely.

2. The same-line double-dragon continuous wave three-stage interlacing scheme is adopted. The end thickness is 1 / 3 of the groove and the end axis is double-row parallel. Therefore, the axial dimension = 3 * 2 = 6 times the groove = 18 mm. However, it is a continuous wave, which is suitable for the current process. There is no cross-groove line and no welding is required.

3. A double-dragon continuous wave three-order variant double-order interleaving scheme is adopted. The end thickness is 1 / 2 of the slot thickness, but the end axial direction is double-row parallel, so the axial dimension = 2*2 = 4 times = 12 mm. However, it is a continuous wave, which is suitable for current technology. There are no cross-slot lines and no welding is required. The end thickness is 1 / 2 of the thickness of the three-order variant double-order continuous wave winding, that is: the end thickness of the three-phase continuous wave scheme is realized. See the attached figure. If the two dragons were to overlap radially, it would be perfect; if they didn't overlap, assembly would be much easier.

4. The earliest patented high-low order interleaving scheme, double ring concentric winding, the thickness is 1 / 2 of the slot, but the end axial direction is double parallel, so the axial dimension = 4 times the slot = 12 mm; but it must be a concentric lap winding, with cross slot lines, which is not suitable for the current continuous processing, requires welding, and is only suitable for 4, 8, and 12 poles, not suitable for 6 and 10 poles.

5. Circuit board designs must be laser welded, butt welded, or pressure welded; pressure welds are divided into axial planar welds and radial arc-face welds.

6. With many layers now, a diagonal cross-slot continuous wave scheme can be used. Six basic units can be set within each slot, and then the arc thickness can be determined. The thickness of the basic unit can be determined based on the arc thickness, which is simply a matter of arrangement! This optimal scheme has almost no solder joints; it can be designed with reference to continuous wave windings. More attention should be paid to the line voltage of the end windings, as the voltage difference cannot be controlled. In fact, it can be controlled, but it is not easy to control. The voltage changes over time, and there will be a maximum and minimum voltage difference at any time. Therefore, at least 0.05mm insulation film should be used between different phases. 0.02 might also work, that would be even more aesthetically pleasing, and it would be perfectly flush without needing to be flared; The connection of branches can be as follows: if 6 branches in the same slot are connected in series, then branches in adjacent slots can be connected in parallel. If adjacent slots are connected in series, then only 3 branches in the same slot are connected in series, and the rest are connected in parallel. Therefore, the connection principle is: the fewest solder joints, the shortest line, and the lowest adjacent voltage. Alternatively, a conductive heat dissipation sleeve can be added to the outside of the end winding, and an aluminum sleeve and expansion component can be pressed tightly in the pressure-binding area to make close contact with the housing, and thermally conductive silicone can be used for installation; at the same time, in order to reduce eddy currents, a similar thin silicon steel sheet stacking scheme can be adopted, and the sheet material can be copper, aluminum, silicon steel, etc. To ensure that all conductors inside the motor are completely insulated from the outside world and air, a final process such as impregnation, vacuum impregnation, potting, or vacuum potting can be adopted. The end windings provide better heat dissipation, allowing the heat to be conducted directly to the enclosure using aluminum blocks. Welding on the other side can be done around the rotor diameter; 72 slots: The number of pole phase slots is 3. According to the lap winding and double-order-high-low order (there is a cross-slot line on the other side, but one less layer, so the line length is equivalent), there are long and short pitches, which will definitely exceed the stator air gap. The preferred solution for 72 slots is that the axial dimension is 3*6=18 minimum value; or diagonal cross-slot-equidistant, which requires an even number of layers, with high interlayer voltage, and a minimum value of 13; it looks more aesthetically pleasing. The other side circuit board solution uses laser peripheral welding, which is thinner and exceeds the air gap radius; or, both sides can use diagonal cross-slots, with one side being integrated with the slot and the other side being an arc-shaped wedge pressure conduction solution. 48 slots: If the number of polar phase slots is 2, then follow the double short-pitch third order; the other side circuit board solution, laser peripheral welding, thinner, 5-7 mm, exceeding the air gap radius; it is still safer to use the arc wedge pressure conductive solution, safer than welding, and has better conductivity; Use the largest possible end cross-section and aluminum conduction heat dissipation to reduce resistance, lower temperature, and reduce skin effect! In summary: Don't worry too much about long-pitch and cross-slot wires, as the actual wire length is about the same. Prioritize concentric lap windings to reduce interlayer voltage. The arc-shaped wedge pressure conductivity solution may be the best solution, and it will also be the best solution for future mass production. It is much better than welding and can even be applied to existing flat wire motors. Yes, the welding end of the existing hairpin flat wire can be pre-formed (similar to my 3D printed parts). Then, half of the flat wire extending from the groove is removed and bent at 90 degrees. The pre-formed end is also bent at 90 degrees and half is removed. The opening can be appropriately widened. After adding pressure-resistant release paper, it is compacted with a wedge ring and then coated and potted with paint! The end size is shorter and the welding process is eliminated, as well as the twisting, cutting, and welding processes. What are the seven major processes? My hairpin flat wire forming technology is simply a matter of stamping and bending copper plates, which can be made extremely compact. By the way, there's no need to bend it 90 degrees to cut it in half; just extrude it directly to 1 / 2 thickness. Both the inside and outside of the groove should be extruded to 1 / 2 thickness. Alternatively, resistance welding can be used, with uniform clamping and one-time resistance welding! The inside of the groove also uses my patented method: stamping and folding. The advantage is using bare copper with a high-temperature resistant insulating layer! Or, after extreme flaring, you don't need to cut it in half for the butt joint. You can also use my extreme flaring solution to greatly reduce the axial dimension of the hair clip, see the 3D printed part! Note: Insulation between sub-layers or even parent layers can also be achieved by coating with insulating varnish. This can be done using the traditional enameled wire coating process for motors, or by impregnation. Alternatively, the conductive areas on both sides of the conductor sheet used for parallel electrical connections can be pre-isolated to ensure that the varnish film does not adhere to the sides during impregnation, thus avoiding a secondary varnish removal process. Or, because such windings do not undergo frequent bending and do not undergo significant mechanical deformation after impregnation, a wider variety of insulating or insulating varnishes can be used, such as heat-resistant metallic varnishes or other high-temperature coatings or films. Note: Some lines on the same plane appearing in the attached diagram are generated by default when converting 3D to 2D and do not represent special shapes. You can refer to the relevant diagrams when reading. The above solution is also applicable to axial flux motors; This invention improves upon previously filed series of "distributed split winding process design and manufacturing methods" by proposing "a design method for end winding assemblies that can reduce the skin effect." Its features include: the end winding is separate and independent from the slot winding; the end winding is composed of several relatively thin wires or enameled wires connected in parallel to form a large total conductive cross-sectional area to meet the requirements of large current conduction; the electrical connection between the end winding and the slot winding can be achieved through conductive surface pressure contact butt welding or welding. See the attached drawings for details and specific implementation examples. To achieve a conductive surface pressure contact butt joint, the butt joint ends need to be machined into a neat and flat cross-section to ensure excellent conductivity of the butt joint connection. In addition, the butt joint ends need to be designed to facilitate the application of pressure, or the entire thin and soft wire needs to be cured, such as by potting and curing, so that it can be fully connected and meet good conductivity after pressure is applied; as shown in Figures 1-3, these are solutions for thin round wire, thin flat wire, etc. Generally, parallel thin wires or enameled wires are brazed at the ends, such as the most common soldering or tin-immersion treatment, so that the ends form a parallel electrical connection. Note: If it is an enameled wire, the insulation varnish needs to be removed from its ends. The conductor can be enameled wire or ultra-flat wire, see relevant prior applications, and the bare copper wire (or bare aluminum wire) can be isolated and insulated with a high-temperature resistant insulation layer; Its conductor cross-section can be round or flat, and the enameled wire can be enameled round or enameled flat; If the fine wire has not undergone curing treatment, pressure contact is not ideal. Welding or brazing methods, such as tin soldering or silver soldering, can be used instead. To ensure high-temperature resistance, hard brazing can be used. The process specifications include: brazing with a filler metal melting point above 450℃ is considered hard brazing; filler metals include copper-based, silver-based, and aluminum-based alloys; commonly used fluxes include borax, boric acid, fluorides, and chlorides; heating methods include flame heating, salt bath heating, resistance heating, and high-frequency induction heating; hard brazed joints have a strength up to 490MPa and are suitable for workpieces subjected to high stress and operating at high temperatures. Soft soldering can also be used. The process instructions include: soldering with a solder melting point below 450℃ is called soft soldering; commonly used solders are tin-lead alloys; commonly used fluxes are rosin, ammonium chloride solution, etc.; commonly used soldering irons and other flame heating methods are used. Technical Notes: Brazing involves heating the brazing filler metal (with a lower melting point than the base metal) and the workpiece together, causing the filler metal to melt (while the workpiece does not melt). The melted filler metal then wets and fills the gaps between the base metals, and the filler metal and base metal diffuse into each other to form a strong bond. Subject Area: Electrical Engineering (First-level Discipline); Thermal Automation, Power Plant Chemistry and Metallurgy (Second-level Disciplines). Brazing is a welding method in which both the filler metal and the workpiece are heated to their melting temperatures simultaneously, and the liquid filler metal fills the gaps between the solid workpieces to join the metals. Before brazing, the oxide film and oil on the contact surfaces of the base materials must be removed to allow the capillary action of the filler metal to function properly after it melts, increasing its wettability and capillary flow. Depending on the melting point of the filler metal, brazing is divided into hard brazing and soft brazing. Brazing results in minimal deformation and smooth, aesthetically pleasing joints, making it suitable for welding precision, complex components made of different materials, such as honeycomb panels, turbine blades, carbide cutting tools, and printed circuit boards. Before brazing, the workpieces must be meticulously processed and thoroughly cleaned to remove oil and excessively thick oxide films, ensuring proper interface clearance. The clearance is generally required to be between 0.01 and 0.1 mm. Compared to fusion welding, only the filler metal melts during brazing, not the base material. Compared to pressure welding, no pressure is applied to the workpieces during brazing. The weld formed by brazing is called a brazed joint. Alternatively, the above scheme can also adopt a similar hairpin flat wire structure, with one end winding and the slot winding connected as a whole, or with the slot integrally formed or welded outside the slot, and the other end winding and the slot winding connected by pressure contact or post-welding. During welding, the protruding end of the slot winding can also be widened to improve the convenience of welding or docking. To ensure mechanical stability, all end windings can be integrally cured and potted after assembly, or cured with ceramic (or a thin layer of high-temperature resistant insulating material such as ceramic, mica, or basalt can be sprayed onto the surface of the end windings; or a uniform high-temperature resistant insulating protective layer can be formed using conventional ceramic-metal surface adhesion processes; or, to ensure good heat dissipation, a discontinuous insulating coating can be used, i.e., supporting and isolating adjacent conductors to achieve insulation), or grouting and curing can be performed using packaging processes similar to integrated circuits, or even using silicate cement for grouting and curing, while considering heat dissipation and thermal conductivity; see attached diagram. Another assembly and positioning scheme for the end winding is to use the end winding + independent aluminum disk carrier frame to make centering and angle fit with the stator housing. It can be positioned at the keyway on the periphery of the corresponding iron core, and then screwed onto the existing end cover by set screws. To further refine the design, the radial shape of the busbar conductive cross-section of the in-slot winding can be transformed into a circumferential arc shape. That is, the busbar conductive cross-section of the in-slot winding is long in the radial dimension and short in the circumferential dimension. By using a conductor to transition and connect it to the end winding, the conductive cross-section is transformed into a conductive cross-section shape with a short radial dimension and a long circumferential dimension. This helps to reduce the space occupied by the end winding, further refine the structure, shorten the conductive path to reduce resistance, reduce material usage, improve efficiency, and reduce costs. Of course, the shape should be changed while keeping the conductive cross-sectional area unchanged as much as possible to ensure the equivalent conductive cross-sectional area; as shown in Figure 3 (see enlarged view for details). Note: In the scheme of reducing the skin effect by opening gaps between conductors in different layers, the gaps between adjacent layers can be staggered, similar to how brick joints between adjacent layers are staggered when building a wall to ensure the final integrated strength. Advantages of separation: The century-old motor manufacturing process has undergone a major transformation, eliminating the need for enameled wire, making rotor assembly easier, eliminating spatial interference, allowing windings to extend beyond the rotor area, simplifying assembly and all processes, eliminating defective products, and enabling the use of matrix windings, regardless of the number of layers; improved temperature resistance, and conductivity can be achieved through pressure; welding is not necessarily better than butt welding, as butt welding involves precision machining, while welding may result in issues such as incomplete or partial welds or defects; good maintainability, high recyclability, and industry advancements; no more damage, even if welding is used; once separated, it means that the process can be diversified, even using photolithography, achieving zero voltage on the same layer, and nanometer-level insulation; To reduce the skin effect and heat dissipation, it can be made thinner and wider, which is the best solution! Patent it immediately; also apply for the process. First, press it into a diagonal seam with the two sides connected, fold it in half, bend it into a circle, and then pot and cure it with the end cap. After removing the connected parts on both sides and processing it into a mirror surface, it can be connected. Alternatively, it can be resistance welded, one-time welded, or high-current welded. Or, the other side can be directly stamped into shape with the winding in the slot in one go, and then welded to the other side, or it can be made into a W-PIN directly. This is especially true for axial flux motors, which can be formed by punching the groove and the end in one go and then bending it. Axial magnetic flux can be achieved by stamping, stacking, and welding the sheets together; or by bending flat wire into a series of circularly wound planar fan shapes, which is the best W-PIN. Regarding the aforementioned online applications, especially 202410619722.9; 202410643792.8; 202410684267.0; 202410796145.0; and 202410815412.4, a method can be adopted where subdivided enameled flat wires are pre-assembled into a coarser matrix flat wire group. That is, each original flat wire with a larger cross-section is subdivided into many smaller cross-section micro-flat wire micro-units. After assembly, each micro-unit is densely and compactly combined to improve slot fill factor. After neat arrangement, they form a coarse flat wire group. Within the same coarse flat wire group, the micro-units are essentially electrically connected in parallel, similar to... The principle of parallel winding of fine enameled wire in a round wire motor reduces the skin effect. This structure is simply referred to as a "matrix flat wire winding", see Figures 4-5. Among them, part numbers 1 and 3 are the outer contours of the matrix flat wire windings; each differential unit of the matrix flat wire windings 2 and 4 is insulated from each other. Note: Figure 4 represents a radial flux motor winding, and Figure 5 represents an axial flux motor winding. Both are described using low-order windings as examples. See prior applications. At the same time, since each thick flat wire group is composed of flat wire micro-units, the overall outer contour shape of the thick flat wire group can be a non-rectangular cross-section. Therefore, the core slot shape can be designed as non-rectangular to further improve the slot fill factor. It can be similar to the core slot shape of a round wire motor. The advantages of "matrix flat wire winding" include reducing the skin effect, greatly increasing the flexibility of the winding, making it easier to bend and shape, causing less damage to the wire, allowing for a larger curvature of bending, and forming a very small bending transition arc, which is conducive to further compaction; in addition, the fine flat wires within the same thick flat wire group are connected in parallel, so the voltage between them is zero, so their insulation film can be very thin, further improving the slot fill factor; The "ultra-flat wire combination method" mentioned multiple times in the previous application can also be used; Alternatively, a coarser flat wire can be formed by combining subdivided flat wire gauges. It is more conducive to heat dissipation, and a pre-set cooling channel network can fully immerse the micro-flat wire windings in the coolant environment. An integral potting, casting, or embedded structure can be adopted to form an integrated module for all end windings, thereby increasing the insulation safety level and mechanical safety, improving insulation and heat dissipation, and reducing electromagnetic noise. Alternatively, prior applications can be consulted. The related applications in this series, especially those concerning 202410619722.9; 202410643792.8; 202410684267.0; 202410796145.0; and 202410815412.4, describe structures that are also applicable to split winding designs, as shown in Figures 1-3. Figure 1 represents single-sided splitting, similar to a hairpin flat wire, inserted from one side and then joined to the other side. Figure 2 represents two-sided splitting, i.e., the winding in the middle slot is independent, and the windings at both ends are also separate. See: 7.11 Independent forming process and design method for end windings in slots of axial flux motors; 7.12 Independent forming process for end windings in slots of motors; 7.15 Split winding forming process and design method for motors (newly applied, application number not yet received). Various welding methods or pressure butt contact electrical connections can be used, or a bare copper plus insulation material solution can be used to improve temperature resistance; Note: This paragraph and the corresponding figures in this application are borrowed from the figures in the previous patent application. This scheme can be used in this application: Figures 24 and 25 illustrate further subdivision of the winding cross-section to reduce the skin effect; 36 is a subdivided conductor; 37 is an outer conductor, and 37 represents the conductive substrate of the same layer, i.e., the flat wire group concept of this application; or, metal 3D printing, printed circuit, photolithography chip forming and other processes can be adopted, 35, 38, and 39 are integral conductor blocks, and all conductors in the 36 and 37 regions can be connected in parallel. Among them, 38 and 39 are integral, which means that the cross-sectional area of ​​the electrical connection can be bent or expanded, which can increase the cross-sectional area of ​​the electrical connection, or the docking space of the end winding can be shifted and dispersed. See the prior application; Figure 25 is similar to the previous ultra-flat wire structure, see earlier application; 40, overall outer contour of ultra-flat wire group; 41, conductor region of ultra-flat wire; 42, insulation region; Similarly, Figure 28 further subdivides the winding cross-section to reduce the skin effect; 45 Each pointing region represents different layers or different flat wire groups, and the basic requirement is that different layers have equal resistance characteristics; 46 Each pointing region represents different conductors in the same layer, which are in parallel and can have different resistance values. Note: This paragraph and its corresponding illustrations are borrowed from the illustrations in the previous patent application, and this design can be used in this application. In Figures 6-9, part numbers 5, 6, 7, 8, and 9 correspond to different axial sections of the motor core and their functions. These improvements address prior applications (such as: 202410619722.9, Second-Order Three-Phase End Winding Process Design and Manufacturing Method, and related prior applications mentioned above). The magnetic flux density uniformity compensation cores 5 and 8 can improve the uneven magnetic flux density distribution caused by insufficient yoke space due to the high-order winding clearance slots. Part number 6 is a magnetic shielding material disc; its function is selective and can be removed. Its addition is to prevent spatial magnetic flux density generation in this area. The increased eddy currents are caused by the circuit, as shown in Figure 6, which points to three types. Any one type can be selected during use; 7. The central main iron core area; 9. The filling compensation iron core fully fills the contact gap between the high-order and low-order end windings and the iron core, so that the magnetic field of the end windings can fully enter the closed main magnetic circuit to participate in excitation, thereby improving the power density and efficiency of the motor; Figure 8 is the overall assembly drawing corresponding to Figure 7, which can also correspond to Figure 9 in the prior application. It is a detailed interpretation of Figure 9 (see prior application "202410619722.9 Second-order three-phase end winding process design and manufacturing method 5.17"); Note: Figures 14-19 of the previous patent application "Motor Separate Winding Molding Process and Design Method 7.15" are all optimized designs to enhance conductivity; among them, part number 33 narrow gap is to reduce skin effect, subdividing the end winding into several parallel copper plates connected in parallel. The above solution is applicable to radial flux and axial flux motors; All independently separated end windings applied for earlier can be pre-formed or independently formed, manufacturing all end windings (including various types such as enameled wire windings, bare copper plate bending plates, etc.) into an integrated flat cylindrical end winding module, which is installed and mated onto the stator core like installing motor end covers, ensuring that the end windings in the end cover correspond one-to-one with the windings in the slot and ensuring a good electrical connection, and ensuring reliable insulation characteristics between them. The electrical connection can be achieved by pressure mating and pressing contact, or by welding, such as high current resistance welding, laser welding, electron beam welding, plasma welding, etc. Including the hairpin winding mentioned in the prior application "Independent forming process of end winding of motor slot winding" in 7.12, after the end winding of the existing hairpin winding is separated, it can also be pre-formed or independently formed, and all hairpin type end windings are manufactured into an integrated end winding flat cylindrical module. It is installed and mated to the stator core like installing motor end cover, and it is ensured that the end winding in the end cover corresponds one-to-one with the slot winding and ensures a good electrical connection relationship, and ensures that there are reliable insulation characteristics between them. The electrical connection method can be pressure mating and pressing contact, or welding method can be used, such as high current resistance welding, laser welding, electron beam welding, plasma welding and other processes. Alternatively, all winding modules can be encapsulated into a single cylindrical ingot; alternatively, a heat dissipation and cooling labyrinth channel can be pre-designed inside; or insulating ceramic material can be installed on the surface of the copper tile, which can be distributed in a mesh, rod, or granular form. In short, it can isolate and insulate adjacent copper tiles while allowing coolant to enter the gaps between the copper tiles. The copper tile has a large surface area and excellent heat dissipation. The side of the integrated end winding module that connects with the slot winding can be precision machined to form a precise flat surface or other curved surfaces that match the slot winding, such as a layout annular cone surface, etc. (as shown in the figure). In short, the mating surfaces of the integrated end winding and the slot winding are precision machined, or even paired and precision machined, so that the two can be precisely and accurately mated to achieve good conductivity. They can be mated by pressure contact to conduct electricity, or by welding processes, such as high-current resistance welding, laser welding, electron beam welding, plasma welding, etc. Clearly, in this series of solutions, both the end windings and the slot windings can be pre-formed and manufactured in advance. The slot windings can be pre-formed into an integral unit before being inserted into the iron core, which can protect the windings and achieve high interlayer density, improving slot fill factor and thermal conductivity. Furthermore, the structure in this application simplifies the slot windings to straight copper rods (commonly known as "copper pillars") and the end windings to bent copper plates (commonly known as "copper tiles"). This is no longer a winding made of enameled wire in the traditional sense. Similar to the ultra-flat wire series motors in the prior application, it allows for the separate design and later synthesis of the conductor layer and insulation layer. This enables the insulation layer to be made of various high-temperature resistant materials, or even air isolation, which greatly improves the heat resistance of the windings, increases the slot fill factor and winding yield, and reduces the process difficulty and cost. See the prior application. Ensure that the inductance of each phase is identical to eliminate circulating current. The above design method applies to relevant prior applications, especially to patent application schemes 202410619722.9; 202410643792.8; 202410684267.0; 202410796145.0; and 202410815412.

4. This principle also applies to axial flux motors; counter-rotating dual rotor motors; and internal and external dual flux types. Axial flux motors can refer to the relevant solutions in the prior application, namely: arranging two or more relatively independent axial flux windings and permanent magnets (or non-permanent magnet current excitation windings) according to the corresponding phase difference angles, and controlling them according to the complementary waveform relationship, can achieve the same effect. Since the axial force of the axial flux motor is very large, it is basically used in the form of double disks or multiple disks to balance the axial force. Moreover, the axial flux motor has the characteristic of short axial dimension. Therefore, it is more advantageous to use the double disk or multiple disk scheme described in this patent application to design a compact high power density motor. It can be a single-rotor or dual-rotor motor, as well as a dual-rotor motor with magnetic flux on both sides and a counter-rotating dual-rotor motor. Its electromagnetic wires can be round or flat; the current waveform can be: square wave, square wave + composite wave, or sine wave; Regarding the method of introducing rotor winding current from the outside for dual-rotor motors, please refer to the prior applications (202211030428.1 Dual-rotor motor current dynamic and static physical ports, 202211098410.5 Constant reluctance rotary transformer and core design and manufacturing method) and the related solutions below; The above solution can also be used for conventional single-rotor motors, such as replacing existing brushless solutions and brushed solutions; The above solution is applicable to all types of electric motors and generators, including asynchronous motors, synchronous motors, brushless motors, brushed motors, induction motors, permanent magnet motors, switched reluctance motors, etc.

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