Stator core and axial flux motor
By incorporating a non-uniform air gap structure in the stator core design of the axial flux motor, the back electromotive force waveform is optimized, thus solving the harmonic problem in the axial flux motor, improving the motor's efficiency and performance, and reducing noise and electromagnetic losses.
Patent Information
- Application Number
- CN202423321858.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2034-12-31
AI Technical Summary
Existing axial flux motors suffer from harmonic distortion affecting performance and require improvement.
The stator core block is designed to face the magnet and has a first region, a second region, and a third region. The second region protrudes relative to the first and third regions and is less distant from the magnet than the first and third regions are from the magnet, forming a non-uniform air gap structure to optimize the back electromotive force waveform and reduce harmonic content.
By optimizing the back EMF waveform, reducing harmonic content, improving the efficiency and performance of the axial flux motor, reducing noise, vibration and electromagnetic losses, and enhancing heat dissipation.
Smart Images
Figure CN223729517U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of electric machines, in particular to a stator core and an axial flux electric machine. BACKGROUND
[0002] Electric machines can be divided into radial flux electric machines and axial flux electric machines, axial flux electric machines are widely concerned due to their compact structure, large torque density and short axial length, and are particularly suitable for occasions where the axial size is limited, but there are still many problems in the current axial flux electric machines that need to be improved, for example, the current axial flux electric machines have many harmonics which affect the performance and there is room for improvement. CONTENT OF THE UTILITY MODEL
[0003] The present application aims to at least partly solve one of the problems in the related art. To this end, the present application provides a stator core.
[0004] To achieve the above-mentioned purpose, the present application discloses a stator core, which is suitable for being arranged in the axial direction of a rotor, the rotor comprising a magnet, the stator core comprising a plurality of core blocks arranged in a ring shape, the core blocks facing the magnet having a first region, a second region and a third region arranged in sequence along the circumferential direction of the stator core, the second region being convex relative to the first region and the third region, and along the axial direction of the stator core, the distance between the second region and the magnet being smaller than the distance between the first region and the magnet, and smaller than the distance between the third region and the magnet.
[0005] In some embodiments of the present application, the first region and the third region are symmetrically arranged about the second region.
[0006] In some embodiments of the present application, the first region and the third region respectively constitute a groove structure, and the first region and one side of the circumferential direction of the core block are in communication, and the third region and the other side of the circumferential direction of the core block are in communication.
[0007] In some embodiments of the present application, the first region and the third region respectively constitute a groove structure, the first region extends along the radial direction of the stator core and is in communication with the two ends of the radial direction of the core block, and the third region extends along the radial direction of the stator core and is in communication with the two ends of the radial direction of the core block.
[0008] In some embodiments of the present application, the second region is convexly arranged in an arc shape towards the magnet.
[0009] In some embodiments of the present application, along the cross section of the stator core in the circumferential direction, in the cross section, the minimum distance between the first region and the third region is W1, and the maximum distance between the first region and the third region is W2, and W2>2*W1 is satisfied.
[0010] In some embodiments of the present application, the core block is adapted to form an air gap with the magnet, and along the axial direction of the stator core, the minimum width of the air gap is L1, and the maximum width of the air gap is L2, and L2>2*L1 is satisfied.
[0011] In some embodiments of the present application, the core block is molded by a soft magnetic composite material.
[0012] The second aspect of the present application discloses an axial flux motor, which comprises a rotor and the above-mentioned stator core, and the stator core is located in the axial direction of the rotor.
[0013] In some embodiments of the present application, the axial direction of the stator core is provided with the rotor on both sides, and the core block is provided with the first region, the second region and the third region facing one side of the rotor, and the core block is provided with the first region, the second region and the third region facing the other side of the rotor.
[0014] The technical scheme of the present application optimizes the back electromotive force waveform of the axial flux motor, reduces the harmonic content, improves the efficiency of the axial flux motor, and improves the performance of the axial flux motor by designing the second region to be convex relative to the first region and the third region, and the distance between the second region and the magnet is less than the distance between the first region and the magnet and the distance between the third region and the magnet.
[0015] Other advantages of the present application will be given in part in the following description, part will become apparent from the following description, or will be understood by those skilled in the art through practice of the present application. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other designs according to the structures shown in the drawings without creative labor.
[0017] Figure 1 The axial flux motor in some embodiments is shown schematically;
[0018] Figure 2 The axial flux motor in some embodiments is shown schematically;
[0019] Figure 3 Fig. 1 is a schematic diagram of a rotor in some embodiments;
[0020] Figure 4 Fig. 2 is a schematic diagram of a stator core in some embodiments;
[0021] Figure 5 Fig. 3 is a schematic diagram of a core block in some embodiments;
[0022] Figure 6 Fig. 4 is a sectional view of a core block in some embodiments;
[0023] Figure 7 Fig. 5 is a schematic diagram of a core block and a magnet cooperation in some embodiments;
[0024] Figure 8 Fig. 6 is a schematic diagram of a core block and a magnet cooperation (showing L1, L2) in some embodiments.
[0025] Brief Description of the Drawings:
[0026] Fig. 1 is a schematic diagram of a rotor in some embodiments; Fig. 2 is a schematic diagram of a stator core in some embodiments; Fig. 3 is a schematic diagram of a core block in some embodiments; Fig. 4 is a sectional view of a core block in some embodiments; Fig. 5 is a schematic diagram of a core block and a magnet cooperation in some embodiments; Fig. 6 is a schematic diagram of a core block and a magnet cooperation (showing L1, L2) in some embodiments.
[0027] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION
[0028] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.
[0029] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications will also change accordingly.
[0030] In the present application, unless specifically defined and limited otherwise, the terms "connected", "fixed", and the like should be interpreted broadly, for example, "fixed" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through an intermediate medium; can be internal connection of two elements, or interaction relationship of two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0031] In addition, in the present application, the description such as "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the fact that the technical solutions can be realized by those skilled in the art. When the combination of technical solutions contradicts each other or cannot be realized, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the present application.
[0032] The first aspect of the present application discloses a stator core 1100, which is adapted to be arranged in the axial direction of a rotor 2000, the rotor 2000 comprising a magnet 2100, in combination Figures 1 to 7 As shown, in some embodiments, the stator core 1100 comprises a plurality of core blocks 1110, the plurality of core blocks 1110 are arranged in an annular manner, the core blocks 1110 have a first region 1111, a second region 1112 and a third region 1113 facing the magnet 2100, the first region 1111, the second region 1112 and the third region 1113 are arranged in sequence along the circumferential direction of the stator core 1100, and the second region 1112 is convex relative to the first region 1111 and the third region 1113 (towards the magnet 2100), along the axial direction of the stator core 1100, the distance between the second region 1112 and the magnet 2100 is less than the distance between the first region 1111 and the magnet 2100, and less than the distance between the third region 1113 and the magnet 2100. By such arrangement, it is beneficial to optimize the back electromotive force waveform of the axial flux motor 3000, reduce the harmonic content, improve the efficiency of the axial flux motor 3000, and improve the performance of the axial flux motor 3000.
[0033] The stator 1000 is further described below in combination with the axial flux motor 3000, which includes the stator 1000 and a rotor 2000, and the rotor 2000 is located in the axial direction of the stator 1000, or the stator 1000 is located in the axial direction of the rotor 2000. It can be understood that the axial flux motor 3000 has various types, which can be in the form of a double-rotor single-stator, a single-rotor double-stator, a single-rotor single-stator, or a multi-rotor multi-stator. The rotor 2000 is the part of the axial flux motor 3000 that can rotate during operation, and the stator 1000 is the part of the axial flux motor 3000 that is fixed during operation.
[0034] The rotor 2000 includes a magnet 2100, and generally includes a support disc 2200. The magnet 2100 is fixed on the support disc 2200, and the magnet 2100 can be fixed on the support disc 2200 in various ways, such as by adhesion, integral molding, or other methods. The magnet 2100 can be made of various materials, such as a rare earth permanent magnet material, a ferrite permanent magnet material, or other composite materials. In this embodiment, the number of magnets 2100 is more than two, and the plurality of magnets 2100 are arranged in a ring shape. In the drawings, the number of magnets 2100 on a single rotor 2000 is 18.
[0035] The stator 1000 includes a stator core 1100, which includes a core block 1110. The number of core blocks 1110 is more than two, and the number of core blocks 1110 in the stator 1000 in the drawings is 18. The plurality of core blocks 1110 are arranged in a ring shape, and each core block 1110 is wound with a corresponding enameled wire (not shown in the drawings).
[0036] An air gap 3100 is formed between the core block 1110 and the magnet 2100, and the air gap 3100 ensures that the rotation of the rotor 2000 does not interfere with the stator 1000. More specifically, the core block 1110 has a first region 1111, a second region 1112, and a third region 1113 facing the magnet 2100, and at least part of the air gap 3100 formed between the core block 1110 and the magnet 2100 is formed between the first region 1111, the second region 1112, the third region 1113, and the magnet 2100, i.e., the first region 1111 and the magnet 2100 form part of the air gap 3100, the second region 1112 and the magnet 2100 form part of the air gap 3100, and the third region 1113 and the magnet 2100 form part of the air gap 3100. In this embodiment, the first region 1111, the second region 1112, and the third region 1113 are arranged in sequence along the circumferential direction of the stator core 1100 (i.e., the circumferential direction of the axial flux motor 3000, where the circumferential direction means the circumferential direction around the central axis of the axial flux motor 3000), and the second region 1112 is located between the first region 1111 and the third region 1113. Along the axial direction of the stator core 1100 (i.e., the axial direction of the axial flux motor 3000, where the radial direction is perpendicular to the axial direction), the distance between the second region 1112 and the magnet 2100 is smaller than the distance between the first region 1111 and the magnet 2100 and the distance between the third region 1113 and the magnet 2100. In this way, the air gap 3100 forms a non-uniform structural feature, which is conducive to optimizing the back EMF waveform of the axial flux motor 3000, reducing the harmonic content, improving the efficiency of the axial flux motor 3000, and improving the performance of the axial flux motor 3000.
[0037] For example, the surface of the magnet 2100 facing the core block 1110 is a plane, and along the axial direction of the stator core 1100, the distance between the second region 1112 and the magnet 2100 is relatively small, and the distance between the first region 1111, the third region 1113, and the magnet 2100 is relatively large. In this way, the air gap 3100 forms a non-uniform structural feature.
[0038] In combination Figures 5 to 7 As shown in some embodiments, the first region 1111 and the third region 1113 are symmetrically arranged about the second region 1112. In this embodiment, by symmetrically arranging the first region 1111 and the third region 1113, it is helpful to reduce the harmonics caused by the non-uniform distribution of the magnetic field, to further modify the back EMF waveform, and to reduce the torque ripple and the cogging torque of the axial flux motor 3000, thereby reducing the noise, vibration, and electromagnetic loss of the axial flux motor 3000 during operation.
[0039] In combination Figure 5As shown, in some embodiments, the first region 1111 and the third region 1113 respectively constitute a groove structure, and the first region 1111 communicates with one side of the circumferential direction of the core block 1110 (i.e. the circumferential direction of the stator core 1100), and the third region 1113 communicates with the other side of the circumferential direction of the core block 1110. Since the first region 1111, the second region 1112 and the third region 1113 are arranged in sequence along the circumferential direction of the stator core 1100, by such arrangement, the center of the air gap 3100 formed between the core block 1110 and the magnet 2100 is relatively narrow, and the circumferential direction of the two sides is relatively wide, which further improves the sine degree of the magnetic field of the air gap 3100, reduces the harmonic component, realizes further correction of the back electromotive force waveform, and the back electromotive force waveform is more smooth.
[0040] Since the second region 1112 is convex relative to the first region 1111 and the third region 1113, and based on the first region 1111 and the third region 1113 constituting a groove structure, such arrangement is conducive to increasing the heat dissipation area of the core block 1110, and is more conducive to heat dissipation of the stator core 1100.
[0041] In combination with Figure 5 As shown, in some embodiments, the first region 1111 and the third region 1113 respectively constitute a groove structure, the first region 1111 extends along the radial direction of the stator core 1100 and communicates with the two ends of the radial direction of the core block 1110, and the second region 1112 extends along the radial direction of the stator core 1100 and communicates with the two ends of the radial direction of the core block 1110.
[0042] By such arrangement, the correction of the waveform of the back electromotive force is strengthened, and the harmonic content is further reduced. On this basis, in some cases, heat dissipation can also be strengthened. For example, taking the axial flux motor 3000 as a double-rotor single-stator form, the two rotors 2000 hold the middle stator 1000, and the heat generated by the stator 1000 is difficult to spread along the axial direction to both sides. In the present embodiment, since the first region 1111 and the third region 1113 respectively constitute a groove structure, and communicate with the two ends of the radial direction of the core block 1110, the internal heat of the stator 1000 can be discharged along the groove structure, and the heat dissipation is strengthened. In addition, if the stator core 1100 is fixed by injection molding, the injection molding strength of the core block 1110 can also be strengthened by the arrangement of the groove structure, and effective support for the stator core 1100 is realized.
[0043] In combination with Figure 7As shown, in some embodiments, the second region 1112 is arranged in an arc shape towards the magnet 2100, compared with the second region 1112 being arranged in a plane, by arranging the second region 1112 in an arc shape towards the magnet 2100, it will help to further reduce the harmonic content, reduce the high frequency component in the back EMF waveform of the axial flux motor 3000, further correct the back EMF waveform, thereby improving the performance and efficiency of the axial flux motor 3000.
[0044] In combination Figure 6 As shown, in some embodiments, along the cross section of the core block 1110 in the circumferential direction of the stator core 1100, in the cross section, the minimum distance between the first region 1111 and the third region 1113 is W1, and the maximum distance between the first region 1111 and the third region 1113 is W2, satisfying the condition W2>2*W1, by limiting W1 and W2, it can realize the limitation of the first region 1111, the second region 1112 and the third region 1113, under the premise of satisfying the condition W2>2*W1, it is more conducive to the optimization of the back EMF waveform, so that the back EMF waveform is closer to a sine wave, further optimizing the performance of the axial flux motor 3000.
[0045] Optionally, in combination Figure 8 As shown, in some embodiments, an air gap 3100 is formed between the core block 1110 and the magnet 2100, along the axial direction of the stator core 1100, the minimum width of the air gap 3100 is L1, and the maximum width of the air gap 3100 is L2, satisfying L2>2*L1.
[0046] Taking the side of the magnet 2100 facing the core block 1110 as an example, the minimum width L1 of the air gap 3100 is formed between the second region 1112 and the magnet 2100, and the maximum width L2 of the air gap 3100 is formed between the first region 1111 and the magnet 2100 and between the third region 1113 and the magnet 2100, by optimizing the size of the air gap 3100, it is also conducive to the optimization of the back EMF waveform, so that the back EMF waveform is closer to a sine wave, further optimizing the performance of the axial flux motor 3000.
[0047] In some embodiments, the core block 1110 is molded from soft magnetic composite material, which is also called soft magnetic composite material, which is a composite material with soft magnetic function composed of soft magnetic ferrite and polymer matrix, and the relatively complex structure shape processing can be completed by molding processing.
[0048] The application also discloses an axial flux motor 3000, in combination Figures 1 to 8As shown, the axial flux motor 3000 comprises the rotor 2000 and the stator core 1100 located axially to the rotor 2000, the stator core 1100 comprises a plurality of core blocks 1110 arranged in an annular manner, the core blocks 1110 have a first region 1111, a second region 1112 and a third region 1113 facing the magnet 2100, the first region 1111, the second region 1112 and the third region 1113 are sequentially arranged along the circumference of the stator core 1100, and the second region 1112 is convex relative to the first region 1111 and the third region 1113 (towards the magnet 2100), along the axial direction of the stator core 1100, the distance between the second region 1112 and the magnet 2100 is smaller than the distance between the first region 1111 and the magnet 2100, and smaller than the distance between the third region 1113 and the magnet 2100, by such arrangement, it is beneficial to optimize the back electromotive force waveform of the axial flux motor 3000, reduce the harmonic content, improve the efficiency of the axial flux motor 3000, and improve the performance of the axial flux motor 3000. It can be understood that the stator core 1100 of the axial flux motor 3000 of the embodiment adopts the technical solutions of the above-mentioned embodiments, and therefore at least has the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here.
[0049] In combination Figures 1 to 2 As shown, in some embodiments, the axial sides of the stator core 1100 are respectively provided with the rotor 2000, that is, the axial flux motor 3000 in the embodiment constitutes a double-rotor single-stator form, the rotor 2000, the stator core 1100 and the rotor 2000 are sequentially arranged and coaxially arranged along the axial direction, the core blocks 1110 of the stator core 1100 facing one side of the rotor 2000 are provided with the first region 1111, the second region 1112 and the third region 1113, and the core blocks 1110 of the stator core 1100 facing the other side of the rotor 2000 are also provided with the first region 1111, the second region 1112 and the third region 1113, so that the axial sides of the stator core 1100 can form non-uniform air gaps 3100, greatly reducing the harmonic content and improving the performance of the double-rotor single-stator form axial flux motor 3000.
[0050] The above-mentioned is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, any equivalent structural transformation made by using the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.
Claims
1. A stator core (1100) adapted to be disposed axially in a rotor (2000), the rotor (2000) including magnets (2100), characterized in that, The stator core (1100) includes a plurality of core blocks (1110) arranged in annular alternation. The core blocks (1110) facing the magnet (2100) have a first region (1111), a second region (1112), and a third region (1113) arranged sequentially along the circumference of the stator core (1100). The second region (1112) protrudes relative to the first region (1111) and the third region (1113) and along the axial direction of the stator core (1100). The distance between the second region (1112) and the magnet (2100) is smaller than the distance between the first region (1111) and the magnet (2100), and smaller than the distance between the third region (1113) and the magnet (2100).
2. The stator core (1100) as described in claim 1, characterized in that, The first region (1111) and the third region (1113) are symmetrically arranged about the second region (1112).
3. The stator core (1100) as described in claim 1, characterized in that, The first region (1111) and the third region (1113) respectively form a groove structure, and the first region (1111) is connected to one side of the iron core block (1110) in the circumferential direction, and the third region (1113) is connected to the other side of the iron core block (1110) in the circumferential direction.
4. The stator core (1100) as described in claim 1, characterized in that, The first region (1111) and the third region (1113) respectively form a groove structure. The first region (1111) extends radially along the stator core (1100) and is connected to both radial ends of the core block (1110). The third region (1113) extends radially along the stator core (1100) and is connected to both radial ends of the core block (1110).
5. The stator core (1100) as described in claim 1, characterized in that, The second region (1112) is provided in an arc shape facing the magnet (2100).
6. The stator core (1100) as described in any one of claims 1 to 5, characterized in that, A cross section of the core block (1110) is made along the circumference of the stator core (1100). In the cross section, the minimum distance between the first region (1111) and the third region (1113) is W1, and the maximum distance between the first region (1111) and the third region (1113) is W2, satisfying W2>2*W1.
7. The stator core (1100) as described in any one of claims 1 to 5, characterized in that, The iron core block (1110) is adapted to form an air gap (3100) with the magnet (2100). Along the axial direction of the stator iron core (1100), the minimum width of the air gap (3100) is L1, and the maximum width of the air gap (3100) is L2, satisfying L2>2*L1.
8. The stator core (1100) as described in any one of claims 1 to 5, characterized in that, The iron core block (1110) is molded from a soft magnetic composite material.
9. An axial flux motor (3000), characterized in that, It includes a rotor (2000) and a stator core (1100) as described in any one of claims 1 to 8, the stator core (1100) being located axially on the rotor (2000).
10. The axial flux motor (3000) as described in claim 9, characterized in that, The stator core (1100) has rotors (2000) on both sides of its axial direction. The core block (1110) facing one side of the rotor (2000) has a first region (1111), a second region (1112), and a third region (1113). The core block (1110) facing the other side of the rotor (2000) has the same first region (1111), second region (1112), and third region (1113).