A coil array structure for an electromagnetic conversion device and an electromagnetic conversion device

Abstract

The application relates to a coil array structure for an electromagnetic conversion device and the electromagnetic conversion device, and belongs to the technical field of electromagnetic energy conversion. The coil array structure comprises a plurality of coil units, each coil unit comprising a first conductor segment for electromagnetic work and a second conductor segment for current conduction; the plurality of first conductor segments are coplanarly arranged on a first reference plane, the second conductor segments are offsetly arranged on a second plane along a thickness direction, and adjacent coil units are staggered and nested through a hollow avoiding area. The coil unit has a trapezoidal or wedge-shaped contour, a stepped offset step is arranged between the second conductor segment and the first conductor segment, and the cross-sectional area of the first conductor segment is smaller than that of the second conductor segment. The electromagnetic conversion device comprises the coil array structure and a magnetic rotor for forming an axial magnetic flux field, and a plurality of groups of the coil array structure and the magnetic rotor can be alternately stacked in layers along a central axis. The application realizes high-density arrangement of the conductors while maintaining a minimum working air gap, and significantly improves the power density and the electromagnetic conversion efficiency.

Description

Technical Field

[0001] This application relates to the field of electromagnetic energy conversion technology, and in particular to a coil array structure for electromagnetic conversion equipment and an electromagnetic conversion equipment. Background Technology

[0002] In electromagnetic conversion devices such as axial flux motors, generators, and electromagnetic actuators, the structural design of the stator coil array directly determines the power density and energy conversion efficiency of the device. In existing technologies, increasing the coil density is commonly used to improve output performance. However, traditional planar coil structures are loosely arranged with a low effective conductor ratio; while the partially overlapping winding scheme used to increase density increases the number of coils, it significantly increases the working air gap thickness between the permanent magnet and the flux return element, leading to a substantial decrease in working flux density and electromagnetic conversion efficiency. Therefore, how to achieve high-density coil arrangement without increasing the working air gap, while balancing high flux utilization and high power density, is a pressing technical problem in this field. Summary of the Invention

[0003] The technical problem to be solved by this application is that it is difficult to balance the existing coil arrangement density and working air gap thickness. In view of the above-mentioned defects of the prior art, a coil array structure and electromagnetic conversion device for electromagnetic conversion equipment are provided, which achieves the maintenance of minimum effective working air gap while high-density nested assembly.

[0004] To solve the above-mentioned technical problems, the technical solution adopted in this application is: A coil array structure for an electromagnetic conversion device is provided, comprising multiple coil units, each coil unit including a first conductor segment and a second conductor segment, the first conductor segment being used for electromagnetic work, and the second conductor segment being used for current conduction. The first conductor segments of the multiple coil units are coplanarly arranged on a first reference plane, and the second conductor segment of each coil unit is offset along the thickness direction and arranged on a second plane. Adjacent coil units achieve staggered nesting of the first conductor segments through hollow avoidance areas.

[0005] Preferably, the first conductor segment is a straight working segment, the second conductor segment is an extension segment connecting the two ends of the first conductor segment, and the hollow avoidance area is formed by the second conductor segment and the first conductor segment forming a hollow structure, with the first conductor segment on one side of the adjacent coil unit inserted into the hollow structure.

[0006] Preferably, the coil unit has a trapezoidal or wedge-shaped profile, and a stepped abrupt shift step is provided between the second conductor segment and the first conductor segment. The stepped abrupt shift step is used to achieve a height transition between the first reference plane and the second plane.

[0007] Preferably, the cross-sectional area of ​​the first conductor segment is smaller than the cross-sectional area of ​​the second conductor segment.

[0008] Preferably, the coil unit is made of flat copper strip with a rectangular cross-section.

[0009] Preferably, the coil array structure is encapsulated within an epoxy resin matrix, the surface of the epoxy resin matrix is ​​provided with a glass fiber reinforcement layer, and the outer side of the glass fiber reinforcement layer is provided with a polytetrafluoroethylene wear-resistant protective layer.

[0010] Preferably, the effective length of the first conductor segment is 42% of the critical radius of the coil array structure, where the critical radius is the radial distance from the central axis of the coil array structure to the outermost end of the first conductor segment.

[0011] This application also provides an electromagnetic conversion device, comprising: A coil array structure includes multiple coil units, each coil unit including a first conductor segment and a second conductor segment. The first conductor segment is used to participate in electromagnetic work, and the second conductor segment is used to conduct current. The first conductor segments of the multiple coil units are coplanarly arranged on a first reference plane, and the second conductor segment of each coil unit is offset along the thickness direction and arranged on a second plane. Adjacent coil units achieve staggered nesting of the first conductor segments through hollow avoidance areas. A magnetic rotor, which, in conjunction with a coil array structure, forms an axial magnetic flux field, and the magnetic lines of force are perpendicular to a first reference plane.

[0012] Preferably, the magnetic rotor includes an upper magnetic rotor and a lower magnetic rotor, and the coil array structure is arranged between the upper magnetic rotor and the lower magnetic rotor; Alternatively, the magnetic rotor may be arranged on one side of the coil array structure, and a soft iron disk may be provided on the other side of the coil array structure as a magnetic flux return element.

[0013] Preferably, the electromagnetic conversion device includes multiple sets of coil array structures and multiple magnetic rotors. The multiple sets of coil array structures and multiple magnetic rotors are arranged in layers and alternately stacked along the same central axis. Each layer of coil array structure operates independently within an independent axial magnetic flux gap formed by the separation of magnetic rotors.

[0014] The beneficial effects of this application are as follows: by decoupling the function and space of the coil unit, all the first conductor segments participating in electromagnetic work are arranged coplanarly on the first reference plane, thereby ensuring that all effective conductors are in the optimal position for magnetic field interaction, maintaining the minimum effective working air gap of the magnetic circuit, and maximizing the utilization of effective magnetic flux; at the same time, the second conductor segment, which only plays the role of current conduction, is shifted to the second plane along the thickness direction, and the hollow avoidance area is used to realize the staggered nesting of the first conductor segments of adjacent coil units. The structure combining functional partitioning and spatial layering avoids the defect of increased air gap caused by traditional overlapping coils. Without increasing the axial dimension of the equipment, the effective conductor arrangement density is doubled, which significantly improves the power density and electromagnetic conversion efficiency of the equipment. By designing differentiated conductor cross-sections, the cross-sectional area of ​​the first conductor segment is smaller than that of the second conductor segment. The current carrying capacity is matched according to whether the conductor segment participates in the work, effectively reducing the resistance loss of the non-work part while ensuring the output performance remains unchanged, thus optimizing the energy efficiency of the equipment. Combined with epoxy resin molding and composite protective structure, the mechanical strength, heat resistance and wear resistance of the coil array are improved, extending the service life of the equipment.

[0015] The electromagnetic conversion device built based on this coil array structure supports single-disc and multi-disc layered alternating stacking assembly. Under the condition of constant outer diameter of the device, it can increase the effective total working area of ​​the coil by increasing the number of stacking layers, breaking through the power limit of the traditional single-layer structure and meeting the development needs of miniaturization and high power density of electromechanical equipment. At the same time, it has good versatility and can be widely adapted to various application scenarios such as rotary motors, linear motors and various electromagnetic actuators. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the present application will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 This is a schematic diagram of the three-dimensional structure of a coil unit in a preferred embodiment of this application; Figure 2 This is a schematic diagram of the coil array nested assembly structure of a preferred embodiment of this application; Figure 3 This is a partial cross-sectional view of the complete annular coil disk according to a preferred embodiment of this application; Figure 4 This is a schematic diagram of a partially enlarged cross-section of the protective structure of the coil disk according to a preferred embodiment of this application; Figure 5 This is a schematic diagram of the nested assembly and wiring structure of a three-phase segmented coil array according to a preferred embodiment of this application; Figure 6 This is a schematic diagram of the axial magnetic flux assembly structure of the dual magnetic rotor clamping coil disk according to a preferred embodiment of this application; Figure 7 This is a schematic diagram of the assembly of a multi-disk stacked high-power coil array according to a preferred embodiment of this application. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, a clear and complete description will be provided below in conjunction with the technical solutions in the embodiments of this application. Obviously, the described embodiments are some embodiments of this application, but not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this application.

[0018] A preferred embodiment of this application provides a coil array structure for an electromagnetic conversion device; this application uses a rotating electric motor as an example for illustration. Figures 1-5 As shown, the system includes multiple coil units, each comprising a first conductor segment and a second conductor segment. The first conductor segment participates in electromagnetic work, while the second conductor segment conducts current. Dividing the coil unit into two parts separates the effective portion that cuts magnetic field lines to generate Lorentz force from the end portion that only serves an electrical connection, allowing for individual optimization of the conductors at both ends for different functional requirements. The first conductor segments of the multiple coil units are coplanarly arranged on a first reference plane, while the second conductor segment of each coil unit is offset along the thickness direction on a second plane. Adjacent coil units achieve staggered nesting of the first conductor segments through hollow clearance areas. Through the spatial layering layout of the first and second planes, all first conductor segments participating in work are at the same height, ensuring uniform and minimized air gaps between them and the magnetic rotor, thereby maximizing magnetic flux utilization. The second conductor segments, which do not perform work, are raised to a non-working plane, freeing up valuable radial arrangement space for the first conductor segments of adjacent coils. It should be noted that this method can also be used in linear motors or arc actuators, where the first conductor segment is the effective work segment perpendicular to the direction of magnetic field movement, and the second conductor segment is the conducting segment parallel to the direction of movement or connected by a bend, in order to satisfy the above-mentioned functional zoning and spatial layering, all of which fall within the protection scope of this application.

[0019] Furthermore, such as Figures 1-2As shown, the first conductor segment is a straight working segment, and the second conductor segment is an extension connecting the two ends of the first conductor segment. The hollow clearance area is formed by the second conductor segment and the first conductor segment enclosing a hollow structure. The first conductor segment on one side of an adjacent coil unit is inserted into this hollow structure. This enclosing hollow structure has a clearly defined receiving cavity. When adjacent coil units are assembled, the first conductor segment of one coil unit is precisely embedded in the hollow clearance area of ​​another coil unit, forming an interlocking nested relationship similar to a jigsaw puzzle. This structure doubles the number of effective conductors per unit circumference without increasing the axial thickness, solving the problems of loose arrangement and low conductor density in traditional planar coils. It also avoids the defects of increased air gap and increased magnetic reluctance caused by traditional overlapping winding.

[0020] Furthermore, such as Figure 1 As shown, the coil unit has a trapezoidal or wedge-shaped profile. A stepped abrupt offset step is provided between the second conductor segment and the first conductor segment to achieve a height transition between the first reference plane and the second plane. The trapezoidal or wedge-shaped profile of the coil unit is adapted to the radial arrangement of the ring array, which can effectively reduce the waste of the fan-shaped gap between adjacent coils. At the same time, the stepped abrupt offset step is a near-vertical bending transition. The abrupt transition shortens the axial projection length of the transition segment and also compresses the space occupied by the non-working area. In addition, the vertical surface of the step can serve as a self-positioning reference during assembly, providing mechanical limits during multi-layer stacking or molding, significantly improving the overall structural rigidity and dimensional accuracy of the array.

[0021] Furthermore, to optimize energy efficiency, the cross-sectional area of ​​the first conductor segment is smaller than that of the second conductor segment. Since the second conductor segment does not participate in electromagnetic energy conversion, its cross-sectional area does not affect torque output, but it directly affects resistance loss. By designing a larger cross-sectional area for the non-operating segment, the current density and Joule heat in this region can be effectively reduced; while keeping the cross-section of the operating segment smaller is to maximize the number of effective conductor turns within the limited slot space.

[0022] Furthermore, the coil unit is made of flat copper strip with a rectangular cross-section. Compared to round wires, flat copper strip with a rectangular cross-section has a higher fill factor within the trapezoidal profile, which can better fit the shape of the stepped abrupt shift, reducing internal gaps and thus further reducing the overall size of the coil unit while ensuring electrical performance.

[0023] Furthermore, such as Figure 4As shown, the coil array structure also includes a three-layer composite structure forming a protective system. The coil array structure is encased in an epoxy resin matrix; a glass fiber reinforcement layer is provided on the surface of the epoxy resin matrix; and a polytetrafluoroethylene (PTFE) wear-resistant protective layer is provided on the outside of the glass fiber reinforcement layer. The epoxy resin matrix fills the coil gaps through vacuum impregnation or molding processes, providing basic insulation performance and structural integrity; the glass fiber reinforcement layer, as the intermediate skeleton, significantly improves the tensile strength and heat resistance of the coil disk, preventing structural deformation caused by high-speed rotation centrifugal force; the outermost PTFE wear-resistant protective layer utilizes its extremely low coefficient of friction and excellent chemical stability to protect the surface of the coil disk from assembly wear and environmental corrosion, extending the service life of the equipment.

[0024] Furthermore, regarding coil dimensions, the effective length of the first conductor segment is 42% of the critical radius of the coil array structure; the critical radius is the radial distance from the central axis of the coil array structure to the outermost end of the first conductor segment. This proportional parameter is not an arbitrarily chosen empirical value, but rather a mathematical extreme value solution based on the electromagnetic torque output model. According to the torque generation principle of the axial flux motor, the electromagnetic torque generated by a single coil... It can be represented as: In the aforementioned public notice, It is a constant related to the winding coefficient. The air gap magnetic flux density is... For conductor current, The effective length of the first conductor segment. Let be the average lever arm radius of the first conductor segment. At the critical radius... Under the constraint of a fixed value, if we assume that the radius of the inner endpoint of the first conductor segment is... The effective length is The average lever arm is .Will Substituting into the torque formula and simplifying, we can see that the torque... It's about the effective length. The torque density function is a quadratic function. Taking the derivative of this function and setting it to zero yields the optimal effective length condition that maximizes torque output. Theoretical calculations show that, after considering the actual magnetic field edge effects and end leakage flux corrections, a critical radius ratio of 42% corresponds precisely to the peak range of the torque density function. Therefore, a coil array designed with these parameters can achieve the theoretically optimal torque output for a given outer diameter.

[0025] Furthermore, the coil array structure is also applicable to other types of electromagnetic conversion devices. In linear motor applications, multiple coil units can be nested sequentially along a straight line. In this case, the first conductor segment is arranged perpendicular to the direction of linear motion to generate thrust, while the second conductor segment extends along the direction of motion and is offset to avoid it. Alternatively, the array can also be made into an arc-shaped segmented structure for use in large-diameter direct-drive turntables or special servo mechanisms.

[0026] An electromagnetic conversion device according to a preferred embodiment of this application, such as... Figures 6-7 As shown, the device includes a coil array structure and a magnetic rotor. The coil array structure adopts the segmented nested array containing multiple coil units described in Embodiment 1. The specific coil array structure is the same as described above and will not be repeated here. The magnetic rotor and the coil array structure work together to form an axial magnetic flux field, and the magnetic lines of force are perpendicular to the first reference plane, thereby achieving high power density. Since all the first conductor segments of the coil units are coplanarly arranged on the first reference plane, when the magnetic lines of force pass through the plane strictly perpendicularly, all the first conductor segments participating in the work can cut the magnetic lines of force with the maximum effective length, thereby generating the maximum Lorentz force or induced electromotive force per unit volume. Compared with the case where the magnetic lines of force and conductors are distributed at complex angles in traditional radial flux motors, the orthogonal coupling method significantly improves the utilization rate of electromagnetic materials.

[0027] Furthermore, this embodiment provides two parallel single-disk assembly configurations to address different application scenarios and performance requirements. For example... Figure 6 The diagram shows a high-performance application configuration. The magnetic rotor includes an upper magnetic rotor and a lower magnetic rotor, with a coil array structure arranged between them. The upper and lower magnetic rotors are positioned opposite each other, with opposite magnetic pole polarities (e.g., N and S poles on opposite sides), thus forming a through-flowing axial main magnetic flux in the region where the coil array structure is located. This double-sided clamping structure fully utilizes the magnetic field energy of the permanent magnets on both sides, maximizing the air gap magnetic flux density. This configuration is suitable for applications such as servo motors and wind turbines where extreme torque density or power generation efficiency is required. In another low-cost or thinner application configuration, the magnetic rotor is arranged on one side of the coil array structure, while a soft iron disk serves as a magnetic flux return element on the other side. In this case, the soft iron disk is made of a high-permeability material and is used to guide the magnetic lines of force to close and form a complete magnetic circuit. Although its air gap magnetic flux density is slightly lower than that of the double-sided magnetic rotor structure, this configuration reduces the amount of permanent magnets by half, significantly lowering manufacturing costs and overall weight. It also reduces the axial dimension, making it ideal for cost-sensitive or space-constrained consumer electronics, miniature fans, and other devices. It should be noted that the core of both double-sided configurations is maintaining the perpendicular penetration characteristic of the axial magnetic flux relative to the first reference plane to ensure the electromagnetic conversion efficiency of the coil array structure.

[0028] Furthermore, in order to break through the single power limit, such as Figure 7 As shown, a multi-disc stacked expansion configuration is also provided. In this configuration, the electromagnetic conversion device includes multiple coil array structures and multiple magnetic rotors. The multiple coil array structures and multiple magnetic rotors are arranged in layers and alternately stacked along the same central axis. It should be noted that the stacking here is a modular combination based on magnetic circuit decoupling. Each layer of coil array structure operates independently within an independent axial magnetic flux gap formed by the separation of magnetic rotors. Each layer of coil array has a dedicated magnetic circuit working area defined by its two adjacent magnetic rotors (or the magnetic rotor at the end and the soft iron disk). The magnetic flux between layers is independent and does not interfere with each other. For example, the coil array located in the middle layer is simultaneously energized by the magnetic rotor above and below, without being affected by the leakage magnetic flux of the outermost magnetic circuit. This technology allows for a linear increase in the total effective working area of ​​the coil by increasing the number of stacked layers, while keeping the overall outer diameter of the device constant. This results in a significant increase in output power, solving the problem of volume expansion caused by increasing the outer diameter or lengthening the axial dimension when expanding the capacity of traditional motors. It enables the device to achieve extremely high power density in a compact space, meeting the urgent needs of electric vehicle drives, industrial precision direct drive, and other fields for high-power, small-volume power sources.

[0029] It should be understood that this application has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this application. Furthermore, based on the teachings of this application, these features and embodiments can be modified to suit specific circumstances and materials without departing from the spirit and scope of this application. Therefore, this application is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this application.

Claims

1. A coil array structure for an electromagnetic conversion device, comprising multiple coil units, each coil unit comprising a first conductor segment and a second conductor segment, the first conductor segment being used for electromagnetic work, and the second conductor segment being used for current conduction, characterized in that: The first conductor segments of multiple coil units are coplanarly arranged on a first reference plane, and the second conductor segment of each coil unit is offset along the thickness direction and arranged on a second plane. Adjacent coil units achieve staggered nesting of the first conductor segments through a hollow clearance area. The first conductor segment is a straight working segment, and the second conductor segment is an extension segment connecting the two ends of the first conductor segment. The hollow clearance area is formed by the second conductor segment and the first conductor segment enclosing a hollow structure. The first conductor segment on one side of an adjacent coil unit is inserted into the hollow structure.

2. The coil array structure according to claim 1, characterized in that: The coil unit has a trapezoidal or wedge-shaped profile. A stepped abrupt shift offset step is provided between the second conductor segment and the first conductor segment. The stepped abrupt shift offset step is used to achieve a height transition between the first reference plane and the second plane.

3. The coil array structure according to claim 1, characterized in that: The cross-sectional area of ​​the first conductor segment is smaller than that of the second conductor segment.

4. The coil array structure according to claim 3, characterized in that: The coil unit is made of flat copper strip with a rectangular cross-section.

5. The coil array structure according to claim 1, characterized in that: The coil array structure is encapsulated in an epoxy resin matrix, and a glass fiber reinforcement layer is provided on the surface of the epoxy resin matrix. A polytetrafluoroethylene wear-resistant protective layer is provided on the outside of the glass fiber reinforcement layer.

6. The coil array structure according to claim 1, characterized in that: The effective length of the first conductor segment is 42% of the critical radius of the coil array structure, and the critical radius is the radial distance from the central axis of the coil array structure to the outermost end of the first conductor segment.

7. An electromagnetic conversion device, characterized in that, include: A coil array structure includes multiple coil units, each coil unit including a first conductor segment and a second conductor segment. The first conductor segment is used to perform electromagnetic work, and the second conductor segment is used to conduct current. The first conductor segments of the multiple coil units are coplanarly arranged on a first reference plane, and the second conductor segment of each coil unit is offset along the thickness direction and arranged on a second plane. Adjacent coil units achieve staggered nesting of the first conductor segments through a hollow clearance area. The first conductor segment is a straight work segment, and the second conductor segment is an extension segment connecting the two ends of the first conductor segment. The hollow clearance area is formed by the second conductor segment and the first conductor segment enclosing a hollow structure. The first conductor segment on one side of an adjacent coil unit is inserted into the hollow structure. A magnetic rotor, which, in conjunction with a coil array structure, forms an axial magnetic flux field, and the magnetic lines of force are perpendicular to a first reference plane.

8. The electromagnetic conversion device according to claim 7, characterized in that: The magnetic rotor includes an upper magnetic rotor and a lower magnetic rotor, and the coil array structure is arranged between the upper magnetic rotor and the lower magnetic rotor; Alternatively, the magnetic rotor may be arranged on one side of the coil array structure, and a soft iron disk may be provided on the other side of the coil array structure as a magnetic flux return element.

9. The electromagnetic conversion device according to claim 8, characterized in that: The electromagnetic conversion device includes multiple sets of coil array structures and multiple magnetic rotors. The multiple sets of coil array structures and multiple magnetic rotors are arranged in layers and alternately stacked along the same central axis. Each layer of coil array structure works independently within the independent axial magnetic flux gap formed by the separation of magnetic rotors.

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