Multipole rotor, electric machine and automobile

Abstract

The application relates to a multi-pole rotor, a motor and a car, which rotates along a central axis of the multi-pole rotor, and the multi-pole rotor comprises a plurality of radial magnets and a plurality of tangential magnets. The plurality of radial magnets are distributed along the circumferential direction of the central axis, and the magnetization direction of the radial magnet is along the radial direction of the central axis; each tangential magnet is arranged between two adjacent radial magnets, and the magnetization direction of the tangential magnet is along the tangential direction of the central axis; along the circumferential direction of the central axis, the angles occupied by the radial magnets and the tangential magnets are different. By adopting the radial magnets and the tangential magnets with different magnetization directions, the plurality of magnets with different magnetization directions jointly form a complete magnetic circuit, the sizes of the radial magnets and the tangential magnets can be designed according to the direction and intensity of the magnetic field, the high-order harmonic content and the cogging torque are reduced, the magnetic field of the motor is more ideal, the motor runs more stably, the motor loss is reduced, and the efficiency of the motor is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the rotor technical field, and particularly relates to a multi-pole rotor, a motor and a vehicle. BACKGROUND

[0002] Traditional slotted motors use a core to guide the magnetic field and support the winding, while the air-core cup motor discards the stator core, which greatly reduces the overall weight and volume of the motor. Due to the removal of the core, the air-core cup motor reduces the energy loss caused by the core, including eddy current loss and hysteresis loss, thereby improving the efficiency of the motor.

[0003] Compared with the traditional slotted motor, although the air-core cup motor does not have stator slots, in actual application, due to the distribution of permanent magnets on the rotor and the unevenness of magnetization, a certain cogging torque will still be generated, which will increase the loss of the motor, reduce the efficiency of the motor, and affect the stability of the system. SUMMARY

[0004] The embodiment of the present application provides a multi-pole rotor, which reduces the cogging torque of the multi-pole rotor to at least partially solve the above technical problems.

[0005] In order to achieve the above-mentioned purpose, according to the first aspect of the present application, a multi-pole rotor is provided, which rotates along a central axis of the multi-pole rotor, and the multi-pole rotor comprises:

[0006] a plurality of radial magnets, which are distributed in a circumferential direction of the central axis, and the magnetization direction of the radial magnet is in a radial direction of the central axis;

[0007] a plurality of tangential magnets, each of which is arranged between two adjacent radial magnets, and the magnetization direction of the tangential magnet is in a tangential direction of the central axis;

[0008] The angles occupied by the radial magnets and the tangential magnets in the circumferential direction of the central axis are different.

[0009] Optionally, the magnetization direction of one of the two adjacent radial magnets is towards the central axis, and the magnetization direction of the other is away from the central axis;

[0010] The magnetization directions of the two adjacent tangential magnets are symmetric about the middle surface of each other.

[0011] Optionally, the ratio of the angle occupied by the radial magnet to the angle occupied by the tangential magnet in the circumferential direction of the central axis is greater than 1 and less than or equal to 2; or,

[0012] The ratio of the angle occupied by the tangential magnet to the angle occupied by the radial magnet is greater than 1 and less than or equal to 2.

[0013] Optionally, four of the radial magnets and four of the tangential magnets are provided, and along the circumferential direction of the central axis, an angle occupied by one of the radial magnets is greater than or equal to 30° and less than 45°, or greater than 45° and less than or equal to 60°, and an angle occupied by one of the tangential magnets is greater than or equal to 30° and less than 45°, or greater than 45° and less than or equal to 60°, and the sum of the angle occupied by one of the radial magnets and the angle occupied by one of the tangential magnets is 90°.

[0014] Optionally, along the circumferential direction of the central axis, an angle occupied by one of the radial magnets is greater than or equal to 37° and less than or equal to 43°, or greater than or equal to 52° and less than or equal to 58°; or, an angle occupied by one of the tangential magnets is greater than or equal to 37° and less than or equal to 43°, or greater than or equal to 52° and less than or equal to 58°.

[0015] Optionally, along the circumferential direction of the central axis, an angle occupied by one of the radial magnets is 40° or 55°, or,

[0016] an angle occupied by one of the tangential magnets is 40° or 55°.

[0017] Optionally, a side of the radial magnet away from the central axis is provided with a first circular arc surface, a side of the tangential magnet away from the central axis is provided with a second circular arc surface, and the first circular arc surface and the second circular arc surface are located on a reference circumferential surface coaxial with the central axis.

[0018] Optionally, a side of an intersection of the radial magnet and the tangential magnet away from the central axis is provided with a tangential groove.

[0019] Optionally, along the circumferential direction of the central axis, a ratio of an angle occupied by the tangential groove to an angle occupied by the tangential magnet and the radial magnet as a whole is greater than or equal to 0.08 and less than or equal to 0.22.

[0020] Optionally, the multipole rotor further comprises a magnetic steel sheath, the magnetic steel sheath is sleeved on the outer circumferential side of the radial magnet and the tangential magnet, and the magnetic steel sheath is in interference fit with the radial magnet and the tangential magnet.

[0021] Optionally, a cavity between the tangential groove and the magnetic steel sheath is used to fill glue to connect the radial magnet, the tangential magnet as a whole and the magnetic steel sheath.

[0022] Optionally, along the circumferential direction of the central axis, angles occupied by each of the radial magnets are the same, and angles occupied by each of the tangential magnets are the same.

[0023] Optionally, the multi-pole rotor further comprises a mandrel coaxially arranged with the central axis, and the radial magnet and the tangential magnet are in abutment with the mandrel on the side thereof facing the central axis.

[0024] Optionally, the tangential magnet is provided with a glue hiding groove on the side thereof facing the central axis, and the glue hiding groove is used to fill glue to connect the tangential magnet and the mandrel.

[0025] Optionally, the glue hiding groove is arranged along the axial direction of the central axis and is located in the middle of the side of the tangential magnet facing the central axis.

[0026] Optionally, the bottom of the glue hiding groove is an arc surface, and the arc surface and the side of the tangential magnet facing the central axis are circularly arc transitioned.

[0027] Optionally, the tangential magnet and / or the radial magnet is a Halbach array magnet.

[0028] According to a second aspect of the present application, an electric machine is provided, comprising the above multi-pole rotor.

[0029] According to a third aspect of the present application, an automobile is further provided, comprising the above multi-pole rotor or the above electric machine.

[0030] In the multi-pole rotor of the embodiments of the present application, the radial magnet and the tangential magnet with different magnetizing directions are adopted, so that the tangential magnet and the two adjacent radial magnets form a magnetic circuit, and the sizes of the radial magnet and the tangential magnet are different, so that more magnetic lines in the magnetic circuit extend along the magnetizing direction of the magnet, the magnetic lines other than the magnetizing direction of the magnet are reduced, the magnetic lines extend along an optimal path, the strength of the magnetic lines is ensured, the content of high-order harmonics and the cogging torque are reduced, the magnetic field of the electric machine is more ideal, the electric machine runs more stably, the loss of the electric machine is reduced, and the efficiency of the electric machine is improved.

[0031] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0033] In order to more completely understand the present application and its beneficial effects, the following will be described in conjunction with the drawings, wherein the same reference numerals in the following description represent the same parts.

[0034] Figure 1 This is a schematic diagram of the structure of the first type of multi-pole rotor provided in an exemplary embodiment of this disclosure;

[0035] Figure 2 This is a schematic diagram of the structure of the second type of multi-pole rotor provided in an exemplary embodiment of this disclosure;

[0036] Figure 3 This is a schematic diagram of the structure of the third type of multi-pole rotor provided in the exemplary embodiments of this disclosure;

[0037] Figure 4 yes Figure 3 A schematic diagram of the magnetic field lines of the third type of multipole rotor is shown.

[0038] Figure 5 This is a schematic diagram of the structure of the fourth type of multi-pole rotor provided in the exemplary embodiments of this disclosure;

[0039] Figure 6 This is a schematic diagram of the structure of the fifth type of multi-pole rotor provided in the exemplary embodiments of this disclosure;

[0040] Figure 7 This is a curve showing the relationship between the angle occupied by the tangential magnet and the cogging torque provided in the exemplary embodiments of this disclosure;

[0041] Figure 8 This is a curve showing the relationship between the angle occupied by the tangential magnet and the back electromotive force provided in the exemplary embodiments of this disclosure;

[0042] Figure 9 yes Figure 1 An enlarged schematic diagram of part A in the middle;

[0043] Figure 10 This is a schematic diagram of the structure of the sixth type of multi-pole rotor provided in the exemplary embodiments of this disclosure;

[0044] Figure 11 yes Figure 10 Enlarged schematic diagram of part B in the middle;

[0045] Figure 12 yes Figure 10 A schematic diagram of the magnetic field lines of the sixth type of multipole rotor is shown.

[0046] Figure 13 yes Figure 10 The curves showing the relationship between the tangential slots and cogging torque of different sizes as a function of time are shown for the sixth type of multi-pole rotor.

[0047] Figure 14 These are the surface magnetic waveform curves of different magnets provided in the exemplary embodiments of this disclosure;

[0048] Figure 15 yes Figure 10Enlarged schematic view of the middle C portion.

[0049] Legend:

[0050] 1. Radial magnet; 11. First circular arc surface; 12. Tangential slot;

[0051] 2. Tangential magnet; 21. Second circular arc surface; 22. Hidden slot;

[0052] 3. Magnetic steel sheath; 4. Mandrel; 5. Central axis; 6. Reference circular surface. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person skilled in the art without creative labor fall within the protection scope of the present application.

[0054] According to the first aspect of the present application, referring to Figures 1 to 3 , a multipole rotor is provided, which rotates along a central axis 5 of the multipole rotor, and the multipole rotor comprises a plurality of radial magnets 1 and a plurality of tangential magnets 2. The plurality of radial magnets 1 are distributed in the circumferential direction of the central axis 5, and the magnetization direction of the radial magnet 1 is in the radial direction of the central axis 5; each tangential magnet 2 is arranged between two adjacent radial magnets 1, and the magnetization direction of the tangential magnet 2 is in the tangential direction of the central axis 5; along the circumferential direction of the central axis 5, the angles occupied by the radial magnet 1 and the tangential magnet 2 are different.

[0055] It can be understood that the magnetization direction of the radial magnet 1 is in the radial direction of the central axis 5, that is, a magnetic field is formed in which the magnetic force lines mainly diverge or converge in the radial direction; the magnetization direction of the tangential magnet 2 is in the tangential direction of the central axis 5, that is, a magnetic field is formed in which the magnetic force lines mainly diverge or converge in the tangential direction. And the angles occupied by the radial magnet 1 and the tangential magnet 2 in the circumferential direction are different, that is, the radial magnet 1 and the tangential magnet 2 are different in size. The magnetic field of the radial magnet 1 and the magnetic field of the tangential magnet 2 are superimposed in space to form a composite magnetic field, the content of high-order harmonics and the cogging torque are low, and the magnetic force line loop of the composite magnetic field is more ideal.

[0056] By setting the radial magnet 1 and the tangential magnet 2 with different magnetization directions and different sizes, the magnetic field of the radial magnet 1 and the magnetic field of the tangential magnet 2 are compounded in space to form a more ideal composite magnetic field, so that more magnetic lines of force in the magnetic circuit extend along the magnetization direction of the magnet, the magnetic lines of force along the optimal path are reduced, the strength of the magnetic lines of force is ensured, thereby reducing the high harmonic content and the tooth slot torque, reducing the additional loss of the motor, and improving the efficiency of the motor; at the same time, the reduction of the magnetic field fluctuation makes the rotation process of the rotor more stable, and the stability of the system is enhanced.

[0057] With reference to Figure 1 and Figure 2 In some embodiments, one of the two adjacent radial magnets 1 has a magnetization direction towards the central axis 5, and the other has a magnetization direction away from the central axis 5; the magnetization directions of the two adjacent tangential magnets 2 are symmetric about the middle surface between them.

[0058] It can be understood that, in the two adjacent radial magnets 1, the magnetic field lines of one radial magnet 1 mainly point to the central axis 5 in the radial direction, and the magnetic field lines of the other radial magnet 1 mainly point away from the central axis 5 in the radial direction; at the same time, the two adjacent tangential magnets 2 are symmetric about the middle surface between them due to the symmetry of the magnetization directions about the middle surface between them; with reference to Figure 4 Each tangential magnet 2 forms an independent magnetic circuit with the two adjacent radial magnets 1, and the two adjacent magnetic circuits are symmetric about the middle surface between them.

[0059] In some embodiments, by alternately arranging the magnetization directions of the adjacent radial magnets 1 towards and away from the central axis 5 and symmetrically distributing the magnetization directions of the adjacent tangential magnets 2, independent magnetic circuits are formed, which can make the magnetic lines of force of the composite magnetic field more in line with the ideal path, and further reduce the content of high harmonics. By arranging the tangential magnet 2 and the radial magnet 1, the stability of the magnetic circuit can be enhanced, the tooth slot torque fluctuation caused by uneven magnetic field distribution can be reduced, thereby further reducing the loss of the motor, improving the efficiency, and improving the stability of the system during operation.

[0060] With reference to Figure 1 and Figure 2 In some embodiments, along the circumference of the central axis 5, the ratio of the angle occupied by the radial magnet 1 to the angle occupied by the tangential magnet 2 is greater than 1 and less than or equal to 2; or, the ratio of the angle occupied by the tangential magnet 2 to the angle occupied by the radial magnet 1 is greater than 1 and less than or equal to 2.

[0061] It can be understood that, along the circumferential direction of the central axis 5, when the ratio of the angle occupied by the radial magnet 1 to the angle occupied by the tangential magnet 2 is greater than 1 and less than or equal to 2, it means that the radial magnet 1 occupies a larger angle range in the circumferential direction than the tangential magnet 2; and when the ratio of the angle occupied by the tangential magnet 2 to the angle occupied by the radial magnet 1 is greater than 1 and less than or equal to 2, it means that the tangential magnet 2 occupies a relatively larger angle range in the circumferential direction.

[0062] In some embodiments, by controlling the size ratio of the radial magnet 1 and the tangential magnet 2 to be greater than 1 and less than or equal to 2 (whether the radial magnet 1 is larger or the tangential magnet 2 is larger), the ratio can be 1.1, 1.16, 1.25, 1.57, 1.8, 2, etc., which can balance the strength of the radial magnetic field and the tangential magnetic field, make the magnetic field line distribution of the composite magnetic field more uniform and conform to the ideal path, further suppress the generation of high-order harmonics, reduce the cogging torque fluctuation caused by uneven magnetic field distribution, thereby further reduce motor loss, improve motor efficiency, and enhance the smoothness of system operation.

[0063] In some examples, the above ratio can be applicable to multi-pole rotors such as four-pole rotors, six-pole rotors, eight-pole rotors, etc. The following examples illustrate various application cases of the above ratio in four-pole rotors, six-pole rotors and eight-pole rotors:

[0064] Referring to Figure 1 and Figure 2 , the four-pole rotor corresponds to an angle of 90° per pole, and the radial magnet 1 and the tangential magnet 2 are respectively provided with 4, and the sum of the angles occupied by one tangential magnet 2 and one radial magnet 1 in the circumferential direction is 90°.

[0065] When the ratio of the radial magnet 1 to the tangential magnet 2 is greater than 1 and less than or equal to 2, if the radial magnet 1 is 30°, then the tangential magnet 2 is 60° (ratio = 2); if the radial magnet 1 is 35°, then the tangential magnet 2 is 55° (ratio ≈ 1.57); and if the radial magnet 1 is 40°, then the tangential magnet 2 is 50° (ratio = 1.25).

[0066] When the ratio of the tangential magnet 2 to the radial magnet 1 is greater than 1 and less than or equal to 2, if the tangential magnet 2 is 60°, then the radial magnet 1 is 30° (ratio = 2); if the tangential magnet 2 is 50°, then the radial magnet 1 is 40° (ratio = 1.25); and if the tangential magnet 2 is 55°, then the radial magnet 1 is 35° (ratio ≈ 1.57).

[0067] Referring to Figure 5 , the six-pole rotor corresponds to an angle of 60° per pole, and the radial magnet 1 and the tangential magnet 2 are respectively provided with 6, and the sum of the angles occupied by one tangential magnet 2 and one radial magnet 1 in the circumferential direction is 60°.

[0068] When the ratio of the radial magnet 1 to the tangential magnet 2 is greater than 1 and less than or equal to 2, if the radial magnet 1 is 20°, the tangential magnet 2 is 40° (ratio = 2); if the radial magnet 1 is 25°, the tangential magnet 2 is 35° (ratio ≈ 1.4); if the radial magnet 1 is 22°, the tangential magnet 2 is 38° (ratio ≈ 1.73).

[0069] When the ratio of the tangential magnet 2 to the radial magnet 1 is greater than 1 and less than or equal to 2, if the tangential magnet 2 is 40°, the radial magnet 1 is 20° (ratio = 2); if the tangential magnet 2 is 35°, the radial magnet 1 is 25° (ratio ≈ 1.4); if the tangential magnet 2 is 38°, the radial magnet 1 is 22° (ratio ≈ 1.73).

[0070] Referring to Figure 6 , the octupole rotor corresponds to an angle of 45° per pole pair, the radial magnet 1 and the tangential magnet 2 are respectively provided with 8, and one tangential magnet 2 and one radial magnet 1 occupy an angle of 45° in the circumferential direction.

[0071] When the ratio of the radial magnet 1 to the tangential magnet 2 is greater than 1 and less than or equal to 2, if the radial magnet 1 is 15°, the tangential magnet 2 is 30° (ratio = 2); if the radial magnet 1 is 18°, the tangential magnet 2 is 27° (ratio ≈ 1.5); if the radial magnet 1 is 20°, the tangential magnet 2 is 25° (ratio = 1.25).

[0072] When the ratio of the tangential magnet 2 to the radial magnet 1 is greater than 1 and less than or equal to 2, if the tangential magnet 2 is 30°, the radial magnet 1 is 15° (ratio = 2); if the tangential magnet 2 is 25°, the radial magnet 1 is 20° (ratio = 1.25); if the tangential magnet 2 is 27°, the radial magnet 1 is 18° (ratio ≈ 1.5).

[0073] Referring to Figure 1 and Figure 2 , in some embodiments, the radial magnet 1 and the tangential magnet 2 are each provided with 4, along the circumference of the central axis 5, one radial magnet 1 occupies an angle greater than or equal to 30° and less than 45°, or greater than 45° and less than or equal to 60°. In addition, one tangential magnet 2 also occupies an angle greater than or equal to 30° and less than 45°, or greater than 45° and less than or equal to 60°, and the sum of the angle occupied by one radial magnet 1 and the angle occupied by one tangential magnet 2 is 90°.

[0074] It can be understood that when the radial magnet 1 and the tangential magnet 2 are respectively provided with 4, the 4 radial magnets 1 and the 4 tangential magnets 2 are alternately distributed in sequence along the circumference, and the four-pole rotor is formed along the circumferential distribution of the central axis 5; wherein the angle occupied by each radial magnet 1 in the circumference is greater than or equal to 30° and less than 45°, or greater than 45° and less than or equal to 60°, the angle occupied by each tangential magnet 2 in the circumference is greater than or equal to 30° and less than 45°, or greater than 45° and less than or equal to 60°, and the sum of the angles of a single radial magnet 1 and a single tangential magnet 2 is 90°. In some examples, such as the angle occupied by the radial magnet 1 is 30°, 35°, 37°, 40°, 43°, 55° or 60°, then the angle occupied by the tangential magnet 2 is 60°, 55°, 43°, 50°, 37°, 35° and 30°. The whole forms a complete circumference of 360° around the central axis 5, constituting a four-pole layout with structural symmetry.

[0075] In some embodiments, by setting 4 radial magnets 1 and 4 tangential magnets 2, and making the sum of the angles of a single radial magnet 1 and a single tangential magnet 2 be 90°, and the respective angles be in the interval of greater than or equal to 30° and less than 45°, greater than 45° and less than or equal to 60°. Referring to Figure 7 , Figure 7 The curve is the relationship between the angle occupied by the tangential magnet 2 and the cogging torque, and the angle is selected in the angle range of greater than or equal to 30° and less than 45° or greater than 45° and less than or equal to 60°, the cogging torque is smaller, and the high-order harmonic content is reduced. Referring to Figure 8 , Figure 8 The curve is the relationship between the angle occupied by the tangential magnet 2 and the back electromotive force, series 1 is the maximum value curve of the back electromotive force, and series 2 is the effective value curve of the back electromotive force. In this embodiment, by adjusting the angle occupied by the tangential magnet 2 on the circumference, the influence on the amplitude of the back electromotive force is small, such as when the tangential magnet 2 changes from 40° to 55°, the maximum value of the back electromotive force changes by 4%, and the effective value of the back electromotive force changes by 1.6%, which can further reflect that the influence on the motor thrust is small, and it has good implementability and stability. Therefore, by selecting the angle in the angle range of greater than or equal to 30° and less than 45° or greater than 45° and less than or equal to 60°, the size ratio of the radial magnetic field and the tangential magnetic field is optimized, the distribution of the magnetic circuit is more uniform, the high-order harmonic content and the cogging torque are reduced, the distribution of the composite magnetic field is more suitable for the working requirements of the four-pole motor, thereby reducing the motor loss, improving the efficiency, and improving the stability of the four-pole rotor during operation.

[0076] Referring to Figure 1 and Figure 2In some embodiments, along the circumference of the central axis 5, the angle occupied by a radial magnet 1 is greater than or equal to 37° and less than or equal to 43°, or greater than or equal to 52° and less than or equal to 58°; or, the angle occupied by a tangential magnet 2 is greater than or equal to 37° and less than or equal to 43°, or greater than or equal to 52° and less than or equal to 58°.

[0077] Understandably, in a four-pole rotor, along the circumference of the central axis 5, when the angle occupied by a radial magnet 1 is greater than or equal to 37° and less than or equal to 43°, the angle occupied by a tangential magnet 2 is greater than or equal to 47° and less than or equal to 53°; and when the angle occupied by a radial magnet 1 is greater than or equal to 52° and less than or equal to 58°, the angle occupied by a tangential magnet 2 is greater than or equal to 32° and less than or equal to 38°, and the sum of the angles of a single radial magnet 1 and a single tangential magnet 2 is 90°. Similarly, when the angle occupied by a tangential magnet 2 is greater than or equal to 37° and less than or equal to 43°, the angle occupied by a radial magnet 1 is greater than or equal to 47° and less than or equal to 53°; and when the angle occupied by a tangential magnet 2 is greater than or equal to 52° and less than or equal to 58°, the angle occupied by a radial magnet 1 is greater than or equal to 32° and less than or equal to 38°, and the sum of the angles of a single radial magnet 1 and a single tangential magnet 2 is 90°.

[0078] In some embodiments, by limiting the circumferential angle range of the radial magnet 1 and the tangential magnet 2, the high-harmonic content of the composite magnetic field superimposed by the radial magnet 1 and the tangential magnet 2 can be further suppressed, referring to... Figure 7 The cogging torque is smaller, thereby reducing the additional losses of the motor, improving motor efficiency, and enhancing the smoothness of system operation.

[0079] Reference Figure 1 and Figure 2 In some embodiments, along the circumference of the central axis 5, a radial magnet 1 occupies an angle of 40° or 55°; or, a tangential magnet 2 occupies an angle of 40° or 55°.

[0080] In some embodiments, setting the angle occupied by the radial magnet 1 to 40° and the angle occupied by the tangential magnet 2 to 50°, or setting the angle occupied by the radial magnet 1 to 55° and the angle occupied by the tangential magnet 2 to 35°, or setting the angle occupied by the tangential magnet 2 to 40° and the angle occupied by the radial magnet 1 to 50°, or setting the angle occupied by the tangential magnet 2 to 55° and the angle occupied by the radial magnet 1 to 35°, can make the intensity and distribution of the radial magnetic field and the tangential magnetic field form a better ratio in the circumferential direction, making the magnetic field line distribution of the composite magnetic field closer to the ideal state, suppressing the high-order harmonic content to the maximum extent, minimizing the cogging torque, thereby further reducing the additional losses of the motor, significantly improving the motor efficiency, and greatly enhancing the stability of the system operation.

[0081] With reference to Figure 1 and Figure 9 In some embodiments, the side of the radial magnet 1 away from the central axis 5 is provided with a first circular arc surface 11, and the side of the tangential magnet 2 away from the central axis 5 is provided with a second circular arc surface 21, and the first circular arc surface 11 and the second circular arc surface 21 are located on the reference circumferential surface 6 coaxial with the central axis 5.

[0082] It can be understood that the first circular arc surface 11 and the second circular arc surface 21 are both on the same reference circumferential surface 6 coaxial with the central axis 5, that is, the outer periphery profiles of the radial magnet 1 and the tangential magnet 2 are on the same circumference, and the radii of the first circular arc surface 11 and the second circular arc surface 21 are equal.

[0083] In some embodiments, by letting the first circular arc surface 11 of the radial magnet 1 and the second circular arc surface 21 of the tangential magnet 2 be on the same coaxial reference circumferential surface 6, the outer periphery dimensions of the two are the same, simplifying the processing and assembly process of the magnet and facilitating manufacturing. Through the above structural design, the magnetic field boundary of the rotor outer periphery is more regular, which can reduce magnetic field distortion, reduce the generation of harmonics, reduce radial vibration caused by uneven magnet, and further reduce motor loss, improve efficiency, and enhance the stability of system operation.

[0084] With reference to Figure 10 and Figure 11 In some embodiments, the side of the intersection of the radial magnet 1 and the tangential magnet 2 away from the central axis 5 is provided with a tangential slot 12.

[0085] It can be understood that the side of the intersection of the radial magnet 1 and the tangential magnet 2 away from the central axis 5 is provided with a tangential slot 12. With reference to Figure 12 The arrangement of the tangential slot 12 can change the direction of the magnetic force lines at the pole transition part (i.e., the intersection of the radial magnet 1 and the tangential magnet 2), reduce the magnetic force line loop that needs to pass through both air and two magnets (the radial magnet 1 and the tangential magnet 2), and make more magnetic force line loops pass through only air and one of the magnets (the radial magnet 1 or the tangential magnet 2).

[0086] In some embodiments, by arranging the tangential slot 12 on the side of the intersection of the radial magnet 1 and the tangential magnet 2 away from the central axis 5, the magnetic force lines passing through multiple media at the pole transition part can be reduced, thereby reducing magnetic field distortion, weakening the peak of the surface magnetic waveform, reducing the content of high-order harmonics, reducing cogging torque, further reducing motor loss, improving efficiency, and enhancing the stability of system operation.

[0087] With reference to Figure 6 and Figure 7In some embodiments, the ratio of the angle occupied by the tangential slot 12 along the circumference of the central axis 5 to the angle occupied by the tangential magnet 2 and the radial magnet 1 as a whole is greater than or equal to 0.08 and less than or equal to 0.22.

[0088] In some examples, the angle of the tangential slot 12 in the four-pole rotor is greater than or equal to 7.2° and less than or equal to 19.8°, including but not limited to 7.2°, 7.7°, 8°, 10°, 12°, 15°, 16°, 17°, 19°, 19.25°, 19.8°.

[0089] In some examples, the angle of the tangential slot 12 in the six-pole rotor is greater than or equal to 4.8° and less than or equal to 13.2°, including but not limited to 4.8°, 5°, 7°, 9°, 11°, 12°, 13°, 13.2°.

[0090] In some examples, the angle of the tangential slot 12 in the eight-pole rotor is greater than or equal to 3.6° and less than or equal to 9.9°, including but not limited to 3.6°, 4°, 5°, 6.5°, 7°, 8.5°, 9.5°, 9.9°.

[0091] Referring to Figure 13 , Figure 13 The curves of the cogging torque over time for different sizes of tangential slots 12. Taking the four-pole rotor as an example, series 1 (the blue curve in Figure 13 ) has a tangential slot 12 occupying a central angle of 7.7°, series 2 (the orange curve in Figure 13 ) has a tangential slot 12 occupying a central angle of 12°, and series 3 (the gray curve in Figure 13 ) has a tangential slot 12 occupying a central angle of 19.25°. In the four-pole rotor, according to the process and implementation effect, the tangential slot 12 occupying a central angle of 12° is preferred, which has a better effect in reducing the cogging torque and reducing the content of high-order harmonics.

[0092] Referring to Figure 14 , Figure 14 The curves of the surface magnetic waveforms of different magnets. Taking the four-pole rotor as an example, series 1 (the blue curve in Figure 14 ) is an equal-division magnet, i.e., the angles occupied by the radial magnet 1 and the tangential magnet 2 are both 45°; series 2 (the orange curve in Figure 14 ) has a tangential magnet 2 occupying an angle of 40° and a radial magnet 1 occupying an angle of 50°, and is provided with a tangential slot 12; series 3 (the gray curve in Figure 14 ) has a tangential magnet 2 occupying an angle of 40° and a radial magnet 1 occupying an angle of 50°. From Figure 14It can be seen that the surface magnetic waveforms of the equal-division magnets (series 1) have more burrs, while the surface magnetic waveforms of the unequal-division permanent magnets (series 2 and series 3) are smoother. The surface magnetic waveforms of the unequal-division permanent magnets provided with the tangential grooves 12 (series 2) are further weakened in the sharp peaks of the surface magnetic waveforms, which can effectively reduce the content of high-order harmonics, reduce motor loss and improve motor efficiency.

[0093] It can be understood that, along the circumference of the central axis 5, the ratio of the angle occupied by the tangential groove 12 to the angle occupied by the whole tangential magnet 2 and radial magnet 1 is greater than or equal to 0.08 and less than or equal to 0.22, which can effectively reduce the magnetic field distortion of the pole transition part, weaken the sharp peaks of the surface magnetic waveforms, further reduce the content of high-order harmonics, reduce the cogging torque, thereby maintaining the motor efficiency and enhancing the stability of the system operation.

[0094] Referring to Figure 10 In some embodiments, the multi-pole rotor further comprises a magnetic steel sleeve 3, which is sleeved on the outer circumferential side of the radial magnet 1 and the tangential magnet 2, and the magnetic steel sleeve 3 is in interference fit with the radial magnet 1 and the tangential magnet 2.

[0095] In some embodiments, by providing the magnetic steel sleeve 3 and using interference fit, the whole of the plurality of radial magnets 1 and the plurality of tangential magnets 2 can be stably wrapped and fixed, the integrity and stability of the rotor structure are enhanced, the loosening or displacement of the magnets during high-speed operation of the rotor is effectively prevented, and the normal working performance of the rotor is ensured.

[0096] Referring to Figure 10 and Figure 11 In some embodiments, the cavity between the tangential groove 12 and the magnetic steel sleeve 3 is used to fill glue to connect the whole of the radial magnet 1 and the tangential magnet 2 with the magnetic steel sleeve 3.

[0097] It can be understood that the tangential groove 12 is used to fill glue, and the connection of the whole of the radial magnet 1 and the tangential magnet 2 with the magnetic steel sleeve 3 is realized through the glue. The material of the magnetic steel sleeve 3 is carbon fiber, stainless steel, etc.

[0098] In some embodiments, by filling glue in the cavity between the tangential groove 12 and the magnetic steel sleeve 3, the connection strength of the whole of the radial magnet 1 and the tangential magnet 2 with the magnetic steel sleeve 3 can be further enhanced, the stability of the rotor structure can be improved by cooperating with the interference fit, the relative sliding between the magnets and the sleeve can be avoided, and the structural reliability of the rotor in long-term operation can be ensured.

[0099] Referring to Figure 10 In some embodiments, along the circumference of the central axis 5, the angles occupied by each radial magnet 1 are the same, and the angles occupied by each tangential magnet 2 are the same.

[0100] It can be understood that, by making the respective radial magnets 1 occupy the same angle along the circumference and the respective tangential magnets 2 occupy the same angle along the circumference, the design is facilitated and the production and manufacturing process is simplified; if a design with different angles is adopted, more parameter variables will be involved, which is not conducive to design, and will also lead to an increase in the number of molds required for production, thereby increasing the cost.

[0101] Referring to Figure 10 In some embodiments, the multipole rotor further comprises a mandrel 4 coaxially arranged with the central axis 5, and the side of the radial magnets 1 and the tangential magnets 2 facing the central axis 5 abuts against the mandrel 4.

[0102] It can be understood that the mandrel 4 is located at the center of the rotor, providing internal support for the radial magnets 1 and the tangential magnets 2, so that they are circumferentially distributed around the mandrel 4. By arranging the mandrel 4 coaxially with the central axis 5 and making the side of the radial magnets 1 and the tangential magnets 2 facing the central axis 5 abut against the mandrel 4, stable internal positioning of the radial magnets 1 and the tangential magnets 2 can be provided, the structural strength of the multipole rotor as a whole is enhanced, the stability of the magnetic field distribution is maintained, the magnetic field distortion caused by the displacement of the magnets is reduced, which helps to reduce high-order harmonics and cogging torque, and improve the efficiency of the motor and the smoothness of the system operation.

[0103] Referring to Figure 10 and Figure 15 In some embodiments, the side of the tangential magnet 2 facing the central axis 5 is provided with a glue hiding groove 22, and the glue hiding groove 22 is used to fill glue to connect the tangential magnet 2 and the mandrel 4.

[0104] In some embodiments, by arranging the glue hiding groove 22 on the side of the tangential magnet 2 facing the central axis 5 and filling glue, the connection strength between the tangential magnet 2 and the mandrel 4 can be enhanced, preventing the tangential magnet 2 from loosening or displacing due to centrifugal force and other effects during rotation of the rotor, ensuring the positional stability of the tangential magnet 2, and helping to maintain the integrity of the magnetic circuit and the regular distribution of the composite magnetic field, thereby reducing the magnetic field distortion caused by the displacement of the magnets, reducing the high-order harmonic content and the cogging torque, and improving the efficiency of the motor and the smoothness of the system operation.

[0105] Referring to Figure 10 and Figure 15 In some embodiments, the glue hiding groove 22 is arranged along the axial direction of the central axis 5 and is located in the middle of the side of the tangential magnet 2 facing the central axis 5.

[0106] It can be understood that the magnetic field lines of the tangential magnet 2 are sparse at the middle part of the side facing the central axis 5, and therefore the glue groove 22 is arranged at the middle part, which has little influence on the magnetic force of the tangential magnet 2 as a whole. Therefore, the glue groove 22 can be used to fill glue to enhance the connection strength of the tangential magnet 2 and the mandrel 4, and the sparse magnetic field lines at the position reduce the adverse influence of the glue groove 22 on the magnetic force of the tangential magnet 2.

[0107] With reference to Figure 10 and Figure 15 In some embodiments, the bottom of the glue groove 22 is an arc surface, and the arc surface and the surface of the tangential magnet 2 on the side facing the central axis 5 are circularly arc-shaped.

[0108] In some embodiments, by setting the bottom of the glue groove 22 as an arc surface and circularly arc-shaped with the surface of the tangential magnet 2 on the side facing the central axis 5, the structural mutation of the tangential magnet 2 at the position can be reduced, the surface of the magnet is smoother, and the magnetic field distortion caused by the structural mutation is reduced. Therefore, by designing the glue groove 22 as an arc surface, the glue filling space can be ensured to enhance the connection strength, the interference with the magnetic field line distribution around the tangential magnet 2 is reduced, the regularity of the composite magnetic field is maintained, the high-order harmonic content and the cogging torque are further reduced, the motor efficiency is improved, and the stability of system operation is enhanced.

[0109] With reference to Figure 10 In some embodiments, the tangential magnet 2 and / or the radial magnet 1 is a Halbach array magnet.

[0110] It can be understood that at least one of the tangential magnet 2 and the radial magnet 1 adopts the structure of a Halbach array magnet, that is, the tangential magnet 2 can be a Halbach array magnet, the radial magnet 1 can be a Halbach array magnet, or both the tangential magnet 2 and the radial magnet 1 are Halbach array magnets. The Halbach array magnet is arranged through a special magnetizing direction, which can strengthen the magnetic field on one side and weaken the magnetic field on the other side, so as to optimize the magnetic field distribution around the magnet.

[0111] In some embodiments, by setting the tangential magnet 2 and / or the radial magnet 1 as a Halbach array magnet, the magnetic field strength of the rotor as a whole can be enhanced, the concentration and uniformity of the magnetic field are improved, and the stability of the composite magnetic field formed by the radial magnet 1 and the tangential magnet 2 is enhanced. In some embodiments, by using the above-mentioned Halbach array magnet, the high-order harmonic in the magnetic field can be further weakened, the cogging torque is reduced, and the operation efficiency and output performance of the motor are improved.

[0112] According to a second aspect of the present application, a motor is provided, which comprises the above-mentioned multipole rotor. The motor has all the beneficial effects of the above-mentioned multipole rotor, and the present disclosure will not be repeated here.

[0113] According to a third aspect of the present application, there is also provided a vehicle comprising the multipole rotor or the motor as described above. The vehicle has all the advantages of the multipole rotor or the motor as described above, and the disclosure will not be repeated here.

[0114] In the description of the present application, the terms "first", "second", are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0115] In the above embodiments, the description of each embodiment is focused on, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0116] The embodiments, implementation manners and related technical features of the present application can be combined or replaced with each other without conflict.

[0117] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification made to the above embodiment without departing from the technical solution of the present application and according to the technical essence of the present application still belongs to the scope of the technical solution of the present application.

Claims

1. A multipole rotor, characterized by, Rotatable along a central axis of the multipole rotor, the multipole rotor comprises: a plurality of radial magnets distributed along a circumferential direction of the central axis, the radial magnets being magnetized in a radial direction of the central axis; a plurality of tangential magnets, each of the tangential magnets being arranged between two adjacent radial magnets, the tangential magnets being magnetized in a tangential direction of the central axis; the radial magnets and the tangential magnets have different angles along the circumferential direction of the central axis; a tangential slot is arranged on a side of the intersection of the radial magnet and the tangential magnet away from the central axis, a wall surface of the tangential slot is a plane, and the tangential slot can change a magnetic field line direction at the intersection of the radial magnet and the tangential magnet; a ratio of an angle occupied by the tangential slot to an angle occupied by the tangential magnet and the radial magnet as a whole is greater than or equal to 0.08 and less than or equal to 0.22 along the circumferential direction of the central axis.

2. The multipole rotor of claim 1, wherein, one of the two adjacent radial magnets is magnetized toward the central axis, and the other is magnetized away from the central axis; magnetization directions of the two adjacent tangential magnets are symmetric about a middle surface of the two tangential magnets.

3. The multipole rotor of claim 1, wherein, a ratio of an angle occupied by the radial magnet to an angle occupied by the tangential magnet is greater than 1 and less than or equal to 2 along the circumferential direction of the central axis; or, a ratio of an angle occupied by the tangential magnet to an angle occupied by the radial magnet is greater than 1 and less than or equal to 2.

4. The multipole rotor of claim 3, wherein, The radial magnets and the tangential magnets are respectively provided with four, one of the radial magnets has an angle greater than or equal to 30° and less than 45° or greater than 45° and less than or equal to 60° along the circumferential direction of the central axis, one of the tangential magnets has an angle greater than or equal to 30° and less than 45° or greater than 45° and less than or equal to 60° along the circumferential direction of the central axis, and the sum of the angle of the radial magnet and the angle of the tangential magnet is 90°.

5. The multipole rotor of claim 4, wherein, one of the radial magnets has an angle greater than or equal to 37° and less than or equal to 43° or greater than or equal to 52° and less than or equal to 58° along the circumferential direction of the central axis; or, one of the tangential magnets has an angle greater than or equal to 37° and less than or equal to 43° or greater than or equal to 52° and less than or equal to 58° along the circumferential direction of the central axis.

6. The multipole rotor of claim 5, wherein, one of the radial magnets has an angle of 40° or 55° along the circumferential direction of the central axis; or, one of the tangential magnets has an angle of 40° or 55° along the circumferential direction of the central axis.

7. The multipole rotor of claim 1, wherein a first circular arc surface is arranged on a side of the radial magnet away from the central axis, a second circular arc surface is arranged on a side of the tangential magnet away from the central axis, and the first circular arc surface and the second circular arc surface are located on a reference circumferential surface coaxial with the central axis.

8. The multipole rotor of claim 1, wherein, The multipole rotor further comprises a magnetic steel sleeve, the magnetic steel sleeve is sleeved on an outer circumferential side of the radial magnet and the tangential magnet, and the magnetic steel sleeve is in interference fit with the radial magnet and the tangential magnet.

9. The multipole rotor of claim 8, wherein, A cavity between the tangential slot and the magnetic steel sleeve is used to fill glue to connect the radial magnet, the tangential magnet as a whole and the magnetic steel sleeve.

10. The multipole rotor of claim 1, wherein, Each of the radial magnets occupies the same angle along the circumference of the central axis, and each of the tangential magnets occupies the same angle.

11. The multipole rotor of claim 1, wherein, The multipole rotor further comprises a mandrel coaxially arranged with the central axis, and the radial magnets and the tangential magnets abut against the mandrel on the side facing the central axis.

12. The multipole rotor of claim 11, wherein, The tangential magnet is provided with a glue hiding groove on the side facing the central axis, and the glue hiding groove is used to fill glue to connect the tangential magnet and the mandrel.

13. The multipole rotor of claim 12, wherein, The glue hiding groove is arranged along the axial direction of the central axis and is located in the middle of the side of the tangential magnet facing the central axis.

14. The multipole rotor of claim 13, wherein, The bottom of the glue hiding groove is an arc surface, and the arc surface and the side of the tangential magnet facing the central axis are circularly arc transitioned.

15. The multipole rotor of claim 13, wherein, The tangential magnet and / or the radial magnet is a Halbach array magnet.

16. An electric machine characterized by The multipole rotor of any one of claims 1-15.

17. An automobile characterized by comprising: The electric machine of claim 16.

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