Rotor assembly, electric machine and electric vehicle

Abstract

The application provides a rotor assembly, a motor and an electric vehicle. The rotor assembly comprises a rotor lamination, wherein the V-shaped opening is provided with an auxiliary slot on one side of the outer periphery; one of the slot holes in the V-shaped opening is close to one side edge of the outer periphery of the rotor lamination, and a first gap is arranged on one end close to the outer periphery of the rotor lamination; the other slot hole in the V-shaped opening is close to one side edge of the outer periphery of the rotor lamination, and a second gap is arranged on one end away from the outer periphery of the rotor lamination. The asymmetric auxiliary slot and / or gap arranged at a specific position of the rotor lamination optimizes the magnetic circuit, controls the torque ripple and the no-load harmonic content of the motor to be within 3%, does not generate axial force, improves the smoothness and reliability of the motor operation, reduces the noise and vibration of the motor, and improves the comfort of the vehicle operation.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electric vehicles, and particularly relates to a rotor assembly, a motor and an electric vehicle. BACKGROUND

[0002] The core power device of a new energy vehicle is mostly a permanent magnet synchronous motor. Compared with electric excitation, the permanent magnet synchronous motor rotor can generate a magnetic field without external energy, thereby saving the energy required for excitation, improving efficiency, and eliminating the excitation winding, brush and commutator structure required by the traditional electric excitation motor, so that the motor structure is simplified and the operation reliability is higher.

[0003] Because the V-shaped magnetic pole has a magnetic gathering function and high torque density, the new energy main drive motor currently mostly adopts this magnetic pole. In order to reduce motor operation harmonics and torque pulsation, thereby reducing electromagnetic noise and fluctuation generated in the vehicle driving process, improving safety and experience, the currently mostly used setting mode is stator skew slot or rotor skew pole; however, skew slot or skew pole not only reduces output torque, but also generates axial force, affecting the service life of motor bearings, spring washers and other parts. SUMMARY

[0004] Therefore, the application provides a rotor assembly, a motor and an electric vehicle, which can solve the problem that skew slot or skew pole in the prior art generates axial force and affects the service life of the motor.

[0005] In order to solve the above problems, the application provides a rotor assembly, comprising:

[0006] The rotor lamination is uniformly provided with a plurality of slot holes for placing magnetic steel in the circumferential direction; adjacent slot holes form a V shape, and the opening faces the outer periphery of the rotor lamination;

[0007] An auxiliary slot is arranged on the outer periphery opposite to the V-shaped opening, and the auxiliary slot is located on one side of the d-axis of the rotor lamination;

[0008] One of the slot holes in the V shape is close to one side of the outer periphery of the rotor lamination, and a first gap is arranged on one end close to the outer periphery of the rotor lamination, so that the magnetic steel inserted in the slot hole and the slot hole wall are spaced apart;

[0009] The other slot hole in the V shape is close to one side of the outer periphery of the rotor lamination, and a second gap is arranged on one end away from the outer periphery of the rotor lamination, so that the magnetic steel inserted in the slot hole and the slot hole wall are spaced apart.

[0010] Optionally, the auxiliary slot and the first gap are located on the same side of the d-axis of the rotor lamination in the V shape.

[0011] Optionally, the auxiliary grooves are provided in at least three, which are distributed circumferentially along the outer periphery.

[0012] Optionally, the auxiliary grooves are provided as arc grooves, the centers of all the arc grooves are located on the same circle with the center of the rotor lamination as the center; the radius of the rotor lamination is provided as R1, the radius of the circle with the center of the arc groove as the center is provided as R2, the radius of the circle with the arc groove as the center is provided as R3, and R2+R3>R1 is satisfied.

[0013] Optionally, R1 is 50mm-100mm, and R3 is 0.3mm-0.5mm.

[0014] Optionally, the auxiliary grooves are provided as three first, second and third grooves which are sequentially close to the d-axis of the rotor lamination, the angle between the line connecting the center of the first groove and the center of the rotor lamination and the nearest q-axis of the rotor lamination is provided as Δ1, and Δ1=13deg-15deg is satisfied; and / or, the angle between the line connecting the center of the first groove and the center of the rotor lamination and the line connecting the center of the second groove and the center of the rotor lamination is provided as Δ2, and Δ2=1.5deg-3deg is satisfied; and / or, the angle between the line connecting the center of the second groove and the center of the rotor lamination and the line connecting the center of the third groove and the center of the rotor lamination is provided as Δ3, and Δ3=1.5deg-3deg is satisfied.

[0015] Optionally, the first gap is provided as a wedge shape, and the corresponding angle is provided as Δ4, and Δ4=0.5deg-1deg is satisfied.

[0016] Optionally, the length of the side corresponding to the first gap is provided as L1, and the oblique side of the first gap intersects with the side; in the extension direction of the side, the length of the first gap is provided as L2, and the length of the other side opposite to the first gap is provided as L3, and L2+L3≤L1 is satisfied, and L3 / L1=0.4-0.6.

[0017] Optionally, the second gap is provided as a wedge shape, and the corresponding angle is provided as Δ5, and Δ5=0.8deg-1.2deg is satisfied.

[0018] Optionally, the length of the side corresponding to the second gap is provided as L1, and the oblique side of the second gap intersects with the side; in the extension direction of the side, the length of the second gap is provided as L4, and the length of the other side opposite to the first gap is provided as L5, and L4+L5≤L1 is satisfied, and L5 / L1=0.4-0.6.

[0019] According to another aspect of the present application, a motor is provided, which comprises the rotor assembly as described above.

[0020] According to another aspect of the present application, there is provided an electric vehicle comprising the rotor assembly as described above or the motor as described above.

[0021] The rotor assembly provided by the present application comprises: a rotor lamination uniformly provided with a plurality of slot holes for placing magnetic steel in the circumferential direction; adjacent slot holes form a V shape, and the opening faces the outer periphery of the rotor lamination; an auxiliary slot is arranged on the outer periphery opposite to the V-shaped opening, and the auxiliary slot is located on one side of the d-axis of the rotor lamination; one of the slot holes in the V shape is close to one side edge of the outer periphery of the rotor lamination, and a first gap is arranged on one end close to the outer periphery of the rotor lamination, so that the magnetic steel inserted into the slot hole is arranged in a spaced manner with the wall of the slot hole; the other slot hole in the V shape is close to one side edge of the outer periphery of the rotor lamination, and a second gap is arranged on one end away from the outer periphery of the rotor lamination, so that the magnetic steel inserted into the slot hole is arranged in a spaced manner with the wall of the slot hole.

[0022] The asymmetric auxiliary slot and / or gap arranged at a specific position of the rotor lamination optimizes the magnetic circuit, controls the torque ripple and the no-load harmonic content of the motor to be within 3%, does not generate axial force, improves the smoothness and reliability of the motor operation, reduces the noise and vibration of the motor, and improves the comfort of the vehicle operation. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 FIG. 1 is a structural schematic diagram of a rotor assembly of an embodiment of the present application;

[0024] Figure 2 FIG. 2 is a partial enlarged view of A in FIG. 1; Figure 1

[0025] Figure 3 FIG. 3 is a partial enlarged view of B in FIG. 1; Figure 1

[0026] Figure 4 FIG. 4 is a structural schematic diagram of a magnetic steel slot in the rotor assembly of the embodiment of the present application;

[0027] Figure 5 FIG. 5 is an output torque detection diagram of a traditional rotor assembly;

[0028] Figure 6 FIG. 6 is an output torque detection diagram of the rotor assembly of the embodiment of the present application;

[0029] Figure 7 FIG. 7 is a no-load harmonic content detection diagram of a traditional rotor assembly;

[0030] Figure 8 FIG. 8 is a no-load harmonic content detection diagram of the rotor assembly of the embodiment of the present application.

[0031] The reference signs are represented as:​​

[0032] 1, rotor lamination; 11, first slot hole; 111, first gap; 12, second slot hole; 121, second gap; 13, auxiliary slot; 131, first slot; 132, second slot; 133, third slot; 2, magnetic steel. DETAILED DESCRIPTION

[0033] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions will be described clearly and completely below with reference to the specific embodiments of the present application and corresponding drawings. Obviously, the described embodiments are only a 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 those skilled in the art without creative work fall within the scope of protection of the present application.

[0034] It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in other than the order illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a list of steps or units does not necessarily limit those steps or units to the clearly listed ones, but can include other steps or units not clearly listed or inherent to those processes, methods, products or devices.

[0035] Reference should be made to Figures 1 to 8 According to the embodiments of the present application, a rotor assembly is shown, comprising:

[0036] The rotor lamination 1 is uniformly provided with a plurality of slot holes for placing magnetic steels 2 in the circumferential direction; adjacent slot holes form a V shape, and the opening faces the outer periphery of the rotor lamination 1;

[0037] The V-shaped opening is provided with an auxiliary slot 13 on the outer periphery opposite to the V-shaped opening, and the auxiliary slot 13 is located on one side of the rotor lamination d-axis; and / or,

[0038] One of the slot holes in the V shape is close to one side edge of the outer periphery of the rotor lamination 1, and a first gap 111 is provided on one end close to the outer periphery of the rotor lamination 1, so that the magnetic steel 2 inserted in the slot hole is spaced apart from the wall of the slot hole; and / or,

[0039] The other slot in the V-shaped slot is close to one side of the outer periphery of the rotor lamination 1, and a second gap 121 is arranged at one end away from the outer periphery of the rotor lamination 1, so that the magnetic steel 2 inserted in the slot is arranged in a spaced manner with the wall of the slot.

[0040] The application sets asymmetric auxiliary slots 13 and / or gaps at specific positions of the rotor lamination, optimizes the magnetic circuit, does not generate axial force, controls the torque ripple and no-load harmonic content of the motor to within 3%, improves the smoothness and reliability of the motor operation, reduces the noise and vibration of the motor, and improves the comfort of the vehicle operation.

[0041] The application uses asymmetric auxiliary slots and / or gaps, all magnetic steels have consistent angles in the axial direction of the rotor, so that no axial force is generated; at the same time, the rotor magnetic resistance and air gap magnetic resistance are changed, the air gap magnetic density is optimized, the air gap magnetic density is more uniform, and the torque ripple and no-load harmonic content of the motor are controlled to within 3%.

[0042] In some embodiments, the auxiliary slots 13 and the first gaps 111 are located on the same side of the d-axis of the rotor lamination 1 in the V-shaped slot.

[0043] Since the auxiliary slots 13 and the first gaps 111 change the magnetic resistance to optimize the air gap magnetic density to achieve torque ripple and harmonic, the auxiliary slots 13 change the air gap magnetic resistance, and the first gaps 111 change the rotor magnetic resistance; the magnetic steels on both sides of the d-axis are symmetrically distributed, the magnetic resistance of the magnetic steels is the largest, the d-axis can be used as a boundary, and the auxiliary slots 13 and the first gaps 111 are optimized.

[0044] In some embodiments, the auxiliary slots 13 are provided in at least three and are distributed in a circumferential direction along the outer periphery. Preferably, the auxiliary slots 13 are arc-shaped slots, and the centers of all the arc-shaped slots are located on the same circle with the center of the rotor lamination 1 as the center; the radius of the rotor lamination 1 is R1, the radius of the circle where the center of the arc-shaped slot is located is R2, and the radius of the circle where the arc-shaped slot is located is R3, and R2+R3>R1 is satisfied. More preferably, R1 is 50mm-100mm, and R3 is 0.3mm-0.5mm.

[0045] Optionally, the auxiliary groove 13 is provided with three first grooves 131, second grooves 132 and third grooves 133 in sequence close to the rotor lamination d-axis, the angle between the line connecting the center of the first groove 131 and the center of the rotor lamination 1 and the nearest rotor lamination q-axis is set as Δ1, and Δ1=13deg-15deg is satisfied; and / or, the angle between the line connecting the center of the first groove 131 and the center of the rotor lamination 1 and the line connecting the center of the second groove 132 and the center of the rotor lamination 1 is set as Δ2, and Δ2=1.5deg-3deg is satisfied; and / or, the angle between the line connecting the center of the second groove 132 and the center of the rotor lamination 1 and the line connecting the center of the third groove 133 and the center of the rotor lamination 1 is set as Δ3, and Δ3=1.5deg-3deg is satisfied.

[0046] The rotor outer circle is shaped, and three grooves, the first groove 131, the second groove 132 and the third groove 133, are excavated; the design structure is an asymmetric hole excavation design of the rotor outer circle, and the asymmetry refers to a symmetric hole excavation structure not related to the magnetic pole center axis (d-axis) on the same pole, but the structure is uniformly distributed on the rotor outer circle, and the relative positions on each pole are the same.

[0047] In some embodiments, the first gap 111 is wedge-shaped, and the corresponding angle is set as Δ4, and Δ4=0.5deg-1deg is satisfied. Preferably, the length of the side corresponding to the first gap 111 is set as L1, the oblique side of the first gap 111 intersects with the side; in the extension direction of the side, the length of the first gap 111 is set as L2, and the length of the other side opposite to the first gap 111 is set as L3, and L2+L3≤L1 is satisfied, and L3 / L1=0.4-0.6.

[0048] The side oblique edge of the first groove 131 hole 11 closest to the rotor outer circle where the magnetic steel 2 is placed is partially widened, which is equivalent to that after the magnetic steel 2 is inserted into the first groove 131 hole 11, the first gap 111 is still reserved.

[0049] In some embodiments, the second gap 121 is wedge-shaped, and the corresponding angle is set as Δ5, and Δ5=0.8deg-1.2deg is satisfied. Preferably, the length of the side corresponding to the second gap 121 is set as L1, the oblique side of the second gap 121 intersects with the side; in the extension direction of the side, the length of the second gap 121 is set as L4, and the length of the other side opposite to the first gap 111 is set as L5, and L4+L5≤L1 is satisfied, and L5 / L1=0.4-0.6.

[0050] In the first slot 131 hole 11 where the first gap 111 is located, the second slot 132 hole 12 is axially symmetrical about the rotor lamination 1d, and the second gap 121 is arranged on the inclined edge away from the inner circle of the rotor lamination 1 and the end close to the inner circle of the rotor lamination 1, so that after the magnetic steel 2 is inserted into the second slot 132 hole 12, the magnetic steel 2 is arranged in a spaced manner with the inclined edge.

[0051] According to another aspect of the present application, a motor is provided, comprising the rotor assembly as described above.

[0052] By setting the auxiliary slot 13 and / or the gap on the rotor lamination 1 as described above, the motor torque ripple and harmonic content are optimized, such as Figures 5-8 By comparison, the torque ripple is reduced from 3.4% to 2.9%, and the torque ripple is controlled within 3%; the harmonic is reduced from 3.66% to 2.76%, and the reduction is 24.6%.

[0053] According to another aspect of the present application, an electric vehicle is provided, comprising the rotor assembly as described above or the motor as described above.

[0054] It is easy for those skilled in the art to understand that the above-mentioned embodiments can be freely combined and superimposed without conflict.

[0055] The above is only the preferred embodiment of the present application, and does not limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and variations can be made, which should be regarded as the protection scope of the present application.

Claims

1. A rotor assembly characterized by, The application relates to a rotor lamination (1) which is uniformly provided with a plurality of slot holes for placing magnetic steel (2) in the circumferential direction; adjacent slot holes form a V shape, and the opening faces the outer periphery of the rotor lamination (1); an auxiliary slot (13) is arranged on the outer periphery opposite to the V-shaped opening; one of the slot holes in the V shape is close to one side of the outer periphery of the rotor lamination (1), and a first gap (111) is arranged on one end close to the outer periphery of the rotor lamination (1); the first gap (111) enables the magnetic steel (2) inserted into the slot hole to be spaced apart from the wall of the slot hole; the other slot hole in the V shape is close to one side of the outer periphery of the rotor lamination (1), and a second gap (121) is arranged on one end away from the outer periphery of the rotor lamination (1); the second gap (121) enables the magnetic steel (2) inserted into the slot hole to be spaced apart from the wall of the slot hole; the auxiliary slot (13) is arranged as three first, second and third slots (131), (132) and (133) which are sequentially close to the d-axis of the rotor lamination; the first, second and third slots (131), (132) and (133) are asymmetrically cut hole structures of the outer circle of the rotor; the first gap (111) and the second gap (121) are wedge-shaped; the first slot hole (11) for placing the magnetic steel (2) is partially widened on the side inclined edge closest to the outer circle of the rotor lamination (1), thereby obtaining the first gap (111); the first slot hole (11) is symmetrically provided with a second slot hole (12) about the d-axis of the rotor lamination (1); the second slot hole (12) is away from the inner circle of the rotor lamination (1) and has an inclined edge on one end close to the inner circle of the rotor lamination (1); the second gap (121) is arranged on the inclined edge, so that the magnetic steel (2) inserted into the second slot hole (12) is spaced apart from the inclined edge. The auxiliary slot (13) and the first gap (111) are located on the same side of the d-axis of the rotor lamination (1) in the V shape. The auxiliary slot (13) is arranged as an arc-shaped slot, and the centers of all the arc-shaped slots are located on the same circle with the center of the rotor lamination (1) as the center; the radius of the rotor lamination (1) is R1, the radius of the circle where the center of the arc-shaped slot is located is R2, and the radius of the circle where the arc-shaped slot is located is R3, and R2+R3>R1 is satisfied. The value range of R1 is 50mm-100mm, and the value range of R3 is 0.3mm-0.5mm. ​ ​ ​ 2. The rotor assembly of claim 1, wherein ​ 3. The rotor assembly of claim 1, wherein ​ 4. The rotor assembly of claim 3, wherein ​ 5. The rotor assembly of claim 3, wherein An included angle between a line connecting a center of the first slot (131) and a center of the rotor lamination (1) and a nearest q-axis of the rotor lamination is set as Δ1, and the included angle Δ1 is in a range of 13 deg-15 deg; and / or, an included angle between a line connecting a center of the first slot (131) and a center of the rotor lamination (1) and a line connecting a center of the second slot (132) and the center of the rotor lamination (1) is set as Δ2, and the included angle Δ2 is in a range of 1.5 deg-3 deg; and / or, an included angle between a line connecting a center of the second slot (132) and the center of the rotor lamination (1) and a line connecting a center of the third slot (133) and the center of the rotor lamination (1) is set as Δ3, and the included angle Δ3 is in a range of 1.5 deg-3 deg.

6. The rotor assembly of claim 1 or 2, wherein The first gap (111) is set as a wedge shape, and a corresponding included angle is set as Δ4, and the included angle Δ4 is in a range of 0.5 deg-1 deg.

7. The rotor assembly of claim 6, wherein A length of a side corresponding to the first gap (111) is set as L1, and an oblique side of the first gap (111) intersects with the side; in a direction of extension of the side, a length of the first gap (111) is set as L2, and a length of another side opposite to the first gap (111) is set as L3, and L2+L3≤L1 is satisfied, and L3 / L1 is in a range of 0.4-0.

6.

8. The rotor assembly of claim 1 or 2, wherein, The second gap (121) is set as a wedge shape, and a corresponding included angle is set as Δ5, and the included angle Δ5 is in a range of 0.8 deg-1.2 deg.

9. The rotor assembly of claim 8, wherein, A length of a side corresponding to the second gap (121) is set as L1, and an oblique side of the second gap (121) intersects with the side; in a direction of extension of the side, a length of the second gap (121) is set as L4, and a length of another side opposite to the first gap (111) is set as L5, and L4+L5≤L1 is satisfied, and L5 / L1 is in a range of 0.4-0.

6.

10. An electric machine characterized by A rotor assembly as claimed in any one of claims 1-9.

11. An electric vehicle, characterized by An electric machine as claimed in claim 10.

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