Electric machine rotor, permanent magnet electric machine and vehicle

Abstract

The application provides a motor rotor, a permanent magnet motor and a vehicle, wherein the motor rotor comprises a rotor body, a plurality of first magnetic steel grooves, the plurality of first magnetic steel grooves are distributed in the circumferential direction of the rotor body, the first magnetic steel grooves on each magnetic pole are asymmetrically distributed along the symmetry axis of the corresponding rotor part of the magnetic pole, a pair of permanent magnets is installed in each first magnetic steel groove, and the pair of permanent magnets are arranged on the left and right sides of the corresponding first magnetic steel groove. In the application, after the positions of the first magnetic steel grooves are determined, the shape and size of each permanent magnet do not need to be adjusted, the geometric shape of the magnetic circuit can be changed, the magnetic field offset is generated, the utilization rate of the reluctance torque is improved, higher torque is achieved under the condition of the same amount of magnetic steel, torque pulsation can be weakened, and the output efficiency of the permanent magnet motor is improved.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet motor technology, and more specifically, to a motor rotor, a permanent magnet motor, and a vehicle. Background Technology

[0002] A permanent magnet synchronous motor (PMSM) is a synchronous motor that generates a synchronous rotating magnetic field by exciting permanent magnets. Based on the permanent magnet structure, it can be classified into two types: surface permanent magnet synchronous motors (SPMSM) and internal permanent magnet synchronous motors (IPMSM). Currently, most motors used in new energy vehicles are permanent magnet motors, with the magnets mostly internally mounted, and the structure being I-shaped, V-shaped, or other combinations. PMSMs have advantages such as simple structure, high power factor, low loss, and high efficiency, but also the disadvantage of high cost of permanent magnets.

[0003] Most permanent magnet motors have symmetrically arranged magnets. However, for electric vehicles that are often used in unidirectional rotation, the symmetrical arrangement of magnets does not achieve the best matching effect between the reluctance torque and the permanent magnet torque, which is not conducive to improving motor efficiency and will also make the air gap magnetic flux density of the motor less sinusoidal.

[0004] There is currently no effective solution to the above problems. Summary of the Invention

[0005] The main objective of this invention is to provide a motor rotor, a permanent magnet motor, and a vehicle to solve the technical problem of how to improve torque output and overall output efficiency of the permanent magnet motor with the same amount of magnets.

[0006] To achieve the above objectives, according to one aspect of the present invention, an electric motor rotor is provided, comprising: a rotor body; a plurality of first magnetic slots, the plurality of first magnetic slots being distributed circumferentially on the rotor body, the first magnetic slots on each magnetic pole being asymmetrically distributed along the axis of symmetry of the rotor portion corresponding to the magnetic pole; and a pair of permanent magnets being installed in each first magnetic slot, the pair of permanent magnets being disposed on the left and right sides of the corresponding first magnetic slot.

[0007] Furthermore, the distance between one of the two permanent magnets installed in the same first magnet slot and the axis of symmetry of the rotor part is L1, and the distance between the other permanent magnet and the axis of symmetry of the rotor part is L2, where L1≠L2.

[0008] Furthermore, the first magnet slot includes: a first slot that passes perpendicularly through the axis of symmetry of the rotor portion; a second slot that is angularly connected to one end of the first slot, and one of a pair of permanent magnets is installed in the second slot; and a third slot that is angularly connected to the other end of the first slot, and the other of a pair of permanent magnets is installed in the third slot; wherein the first slot, the second slot, and the third slot form a trapezoidal structure with an open end, and the open end of the trapezoidal structure is disposed away from the axis of the rotor body.

[0009] Furthermore, a first magnetic barrier is formed at the end of the second slot away from the first slot, and a second magnetic barrier is formed at the end of the third slot away from the first slot. The cross-sectional areas of the first magnetic barrier and the second magnetic barrier are set differently.

[0010] Furthermore, the rotor body is provided with a second magnetic steel slot, which is arranged in a one-to-one correspondence with the first magnetic steel slot, and at least one third magnetic barrier is provided between the ends of the second magnetic steel slot and the first magnetic steel slot.

[0011] Furthermore, the second magnetic groove has a straight or V-shaped structure.

[0012] Furthermore, the third magnetic barrier is a circular or polygonal aperture.

[0013] Furthermore, magnetic barriers are formed at both ends of the second magnetic groove.

[0014] According to another aspect of the present invention, a permanent magnet motor is provided, including a motor rotor, wherein the motor rotor is the motor rotor described above.

[0015] According to another aspect of the present invention, a vehicle is provided, including a permanent magnet motor having the motor rotor described above.

[0016] Applying the technical solution of this invention, the first magnet slots are asymmetrically distributed along the axis of symmetry of the rotor portion corresponding to the magnetic pole. Each first magnet slot contains a pair of permanent magnets, positioned on the left and right sides of the corresponding slot. That is, the positions of the two permanent magnets in a pair are asymmetrically arranged about the axis of symmetry of the rotor portion. This structure, by gradually determining the position of the first magnet slots based on the centrally connected slot shape, allows the first magnet slots to be asymmetrically distributed along the axis of symmetry of the rotor portion corresponding to the magnetic pole. Without adjusting the shape and size of each permanent magnet, the geometry of the magnetic circuit can be changed, generating a magnetic field offset, improving the utilization rate of reluctance torque, achieving higher torque with the same amount of magnets, and reducing torque ripple, thereby improving the output efficiency of the permanent magnet motor. Simultaneously, the centrally connected structure eliminates the original magnetic bridge, further increasing the motor's torque. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0018] Figure 1 A schematic diagram of the structure of one embodiment of an optional motor rotor according to the present invention is shown;

[0019] Figure 2 A schematic diagram of a structural embodiment of an alternative motor rotor according to the present invention is shown;

[0020] Figure 3 A schematic diagram of another alternative embodiment of the motor rotor according to the present invention is shown.

[0021] The above figures include the following reference numerals:

[0022] 10. Rotor body; 11. Axis of symmetry of the rotor section;

[0023] 20. First magnetic groove; 21. First slot; 22. Second slot; 23. Third slot; 24. First magnetic barrier; 25. Second magnetic barrier;

[0024] 30. Second magnetic steel trough;

[0025] 40. The Third Magnetic Barrier;

[0026] 50. Permanent magnet. Detailed Implementation

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided so that the disclosure of this application is thorough and complete, and that the concept of these exemplary embodiments is fully conveyed to those skilled in the art. In the drawings, for clarity, the thickness of layers and regions may be exaggerated, and the same reference numerals are used to denote the same devices, and therefore their description will be omitted.

[0031] Combination Figures 1 to 3 As shown, according to a specific embodiment of this application, a motor rotor is provided.

[0032] like Figure 1 As shown, the motor rotor includes a rotor body 10, first magnet slots 20, and permanent magnets. There are multiple first magnet slots 20, distributed circumferentially on the rotor body 10. The first magnet slots 20 on each magnetic pole are asymmetrically distributed along the axis of symmetry 11 of the rotor portion corresponding to the magnetic pole. Each first magnet slot 20 contains a pair of permanent magnets 50, positioned on the left and right sides of the corresponding first magnet slot 20.

[0033] It should be noted that, as Figure 1 Taking the structure of one-eighth of the motor rotor as an example, two of the permanent magnets 50 in a pair are located on the left and right sides of the first magnetic slot 20. Since the first magnetic slot 20 is asymmetrically distributed along the axis of symmetry 11 of the rotor portion corresponding to the magnetic pole, the positions of the two permanent magnets 50 in the pair are asymmetrically set with respect to the axis of symmetry 11 of the rotor portion. Specifically, the angle between one of the permanent magnets 50 and the axis of symmetry 11 of the rotor portion is C1, and the angle between the other permanent magnet 50 in the pair and the axis of symmetry 11 of the rotor portion is C2, where C1 ≠ C2.

[0034] In the embodiments of this application, the first magnet slots 20 are asymmetrically distributed along the axis of symmetry 11 of the rotor portion corresponding to the magnetic poles. Each first magnet slot 20 contains a pair of permanent magnets 50, positioned on the left and right sides of the corresponding first magnet slot 20. That is, the positions of the two permanent magnets 50 in a pair are asymmetrically arranged about the axis of symmetry 11 of the rotor portion. With this structure, once the positions of the first magnet slots 20 are determined, the shape and size of each permanent magnet 50 do not need to be adjusted to change the geometry of the magnetic circuit, generating a magnetic field offset, improving the utilization rate of reluctance torque, achieving higher torque with the same amount of magnets, and reducing torque ripple, thereby improving the output efficiency of the permanent magnet motor. Simultaneously, the centrally connected structure eliminates the original magnetic isolation bridge, further increasing the motor's torque.

[0035] Furthermore, such as Figure 1 As shown, the distance between one of the two permanent magnets 50 installed in the same first magnet slot 20 and the axis of symmetry 11 of the rotor part is L1, and the distance between the other permanent magnet 50 and the axis of symmetry 11 of the rotor part is L2, where L1≠L2. Because the two permanent magnets 50 have different offset angles relative to the axis of symmetry 11 of the rotor part, the distances between the two permanent magnets 50 and the axis of symmetry 11 of the rotor part are also different, further changing the geometry of the magnetic circuit, generating magnetic field offset, and improving the utilization rate of reluctance torque.

[0036] Specifically, the first magnet slot 20 includes a first slot 21, a second slot 22, and a third slot 23. The first slot 21 passes perpendicularly through the axis of symmetry 11 of the rotor portion. The second slot 22 is connected at an angle to one end of the first slot 21, and one of a pair of permanent magnets 50 is installed in the second slot 22. The third slot 23 is connected at an angle to the other end of the first slot 21, and the other of a pair of permanent magnets 50 is installed in the third slot 23. The first slot 21, the second slot 22, and the third slot 23 form a trapezoidal structure with an open end, and the open end of the trapezoidal structure is located away from the axis of the rotor body 10.

[0037] In this embodiment, the first slot 21, the second slot 22 and the third slot 23 are all rectangular slots. The distance from the first end of the first slot 21 to the axis of symmetry 11 of the rotor part is L3, and the distance from the second end of the first slot 21 to the axis of symmetry 11 of the rotor part is L4, wherein L3≠L4.

[0038] like Figure 1As shown, a first magnetic barrier 24 is formed at the end of the second slot 22 away from the first slot 21, and a second magnetic barrier 25 is formed at the end of the third slot 23 away from the first slot 21. The cross-sectional areas of the first magnetic barrier 24 and the second magnetic barrier 25 are different. Specifically, the shape of the first magnetic barrier 24 can be different from the shape of the second magnetic barrier 25, or the size of the first magnetic barrier 24 can be different from the size of the second magnetic barrier 25. The overall rotor asymmetric structure, consisting of the first magnetic steel slot 20, the two end second magnetic steel slots 30, and the built-in permanent magnet 50, adjusts the shape of the rotor path, generates a magnetic field offset, and increases the torque density with a fixed amount of magnets.

[0039] As an alternative implementation method, such as Figure 2 As shown, the rotor body 10 is provided with a second magnet slot 30, which is arranged in a one-to-one correspondence with the first magnet slot 20. At least one third magnetic barrier 40 is provided between the ends of the second magnet slot 30 and the first magnet slot 20. Specifically, the shape of the second magnet slot 30 is the same as that of the first magnet slot 20, but the size is different, and the second magnet slot 30 is arranged parallel to the first magnet slot 20. The third magnetic barrier 40 is a circular hole or a polygonal hole. The third magnetic barrier 40 changes the magnetic flux flow direction, reduces output torque pulsation and radial electromagnetic force, and improves the NVH performance of the motor. Magnetic barriers are formed at both ends of the second magnet slot 30. The magnetic barriers at both ends can be designed with different shapes or different sizes.

[0040] As an alternative implementation, the second magnetic groove 30 can be a straight-line or V-shaped structure. Specifically, such as... Figure 3 As shown, the second magnet slot 30 has a straight-line structure and is located at the open end of the first magnet slot 20. The second magnet slot 30 passes perpendicularly through the axis of symmetry 11 of the rotor portion. The distance from the first end of the second magnet slot 30 to the axis of symmetry 11 of the rotor portion is not equal to the distance from the second end of the second magnet slot 30 to the axis of symmetry 11 of the rotor portion. The distance from the first end of the permanent magnet 50 located in the second magnet slot 30 to the axis of symmetry 11 of the rotor portion is a, and the distance from the second end of the permanent magnet 50 located in the second magnet slot 30 to the axis of symmetry 11 of the rotor portion is b, where a≠b.

[0041] According to another specific embodiment of the present invention, a permanent magnet motor is provided, including a motor rotor, wherein the motor rotor is the motor rotor in the above embodiment.

[0042] According to another specific embodiment of the present invention, a vehicle is provided, including a permanent magnet motor having a motor rotor as described in the above embodiments.

[0043] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0044] In addition to the above, it should be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this invention.

[0045] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A motor rotor, characterized in that, include: Rotor body (10); The first magnet slot (20) is multiple, and the multiple first magnet slots (20) are distributed in the circumferential direction of the rotor body (10). The first magnet slots (20) on each magnetic pole are asymmetrically distributed along the axis of symmetry (11) of the rotor part corresponding to the magnetic pole. Each of the first magnetic steel grooves (20) is equipped with a pair of permanent magnets (50), and the pairs of permanent magnets (50) are located on the left and right sides of the corresponding first magnetic steel grooves (20); The distance between one of the two permanent magnets (50) installed in the same first magnet slot (20) and the axis of symmetry (11) of the rotor portion is L1, and the distance between the other permanent magnet (50) and the axis of symmetry (11) of the rotor portion is L2, wherein L1≠L2; The first magnetic groove (20) includes: The first slot (21) passes perpendicularly through the axis of symmetry (11) of the rotor portion. The second slot (22) is connected at an angle to one end of the first slot (21), and one of the permanent magnets (50) is installed in the second slot (22). The third slot (23) is connected at an angle to the other end of the first slot (21), and the third slot (23) is equipped with the other permanent magnet (50) of the pair of permanent magnets (50). The first slot (21), the second slot (22) and the third slot (23) are arranged to form a trapezoidal structure with an open end, and the open end of the trapezoidal structure is set away from the axis of the rotor body (10). The first slot (21), the second slot (22) and the third slot (23) are all rectangular slots. The distance from the first end of the first slot (21) to the axis of symmetry (11) of the rotor part is L3, and the distance from the second end of the first slot (21) to the axis of symmetry (11) of the rotor part is L4, wherein L3 ≠ L4. A first magnetic barrier (24) is formed at the end of the second slot (22) away from the first slot (21), and a second magnetic barrier (25) is formed at the end of the third slot (23) away from the first slot (21). The cross-sectional area of ​​the first magnetic barrier (24) is set differently from that of the second magnetic barrier (25). The rotor body (10) is provided with a second magnetic steel groove (30), the second magnetic steel groove (30) is provided in a one-to-one correspondence with the first magnetic steel groove (20), and at least one third magnetic barrier (40) is provided between the ends of the second magnetic steel groove (30) and the first magnetic steel groove (20). The second magnetic groove (30) has a straight or V-shaped structure; The second magnetic groove (30) has the same shape as the first magnetic groove (20), but different in size. The second magnetic groove (30) is arranged parallel to the first magnetic groove (20).

2. The motor rotor according to claim 1, characterized in that, The third magnetic barrier (40) is a circular hole or a polygonal hole.

3. The motor rotor according to claim 1, characterized in that, Magnetic barriers are formed at both ends of the second magnetic groove (30).

4. A permanent magnet motor, comprising a motor rotor, characterized in that, The motor rotor is the motor rotor according to any one of claims 1-3.

5. A vehicle comprising a permanent magnet motor, characterized in that, The permanent magnet motor has a motor rotor as described in any one of claims 1-3.

Images