CN220915016U - Rotor and spoke type permanent magnet motor - Google Patents

Abstract

The utility model discloses a rotor and spoke type permanent magnet motor, wherein the rotor comprises a rotor iron core and permanent magnets, and the permanent magnets and the rotor iron cores are sequentially and alternately arranged along the circumferential direction of the rotor; the rotor core comprises a core body and auxiliary salient poles, the auxiliary salient poles are arranged on the outer side of the core body, the size of each auxiliary salient pole in the radial direction of the rotor is increased and then reduced along the circumferential direction of the rotor, and the outer contour surfaces of the auxiliary salient poles extend to the outer circumferential surface of the core body at two ends of the circumferential direction of the rotor; the projection of the outer contour surface of the auxiliary salient pole on the end surface of the rotor forms a contour line, and the contour line is an inverse cosine curve. When the rotor provided by the embodiment of the utility model is applied to the spoke type permanent magnet motor, the cogging torque and the air gap harmonic wave of the spoke type permanent magnet motor can be reduced, so that the torque pulsation output by the spoke type permanent magnet motor is weakened.

Description

Rotor and spoke permanent magnet motor

Technical Field

The utility model relates to the technical field of spoke-type permanent magnet motors, in particular to a rotor and a spoke-type permanent magnet motor.

Background technique

Permanent magnet motors, especially NdFeB rare earth permanent magnet motors, have the advantages of small size, light structure, and reliable operation, and are therefore widely used in many fields from automobiles to aerospace. In recent years, with the continuous exploitation of rare earth resources and the implementation of relevant protection policies, the price of rare earths in the international market has continued to rise. The rotor structure of the spoke permanent magnet motor has a magnetic field concentration effect, which is conducive to improving the torque density of the motor, can greatly improve the utilization rate of permanent magnets, and reduce the material cost of permanent magnet motors. Therefore, the spoke permanent magnet motor has become a research hotspot in recent years.

The related art discloses a spoke-type permanent magnet motor, in which the rotor is rotatably arranged in the stator, an air gap is formed between the stator and the rotor, and the air gap is evenly distributed along the circumference of the rotor; the rotor includes a rotor core and permanent magnets, and the permanent magnets are arranged in the rotor core in a manner similar to wheel spokes. When the above rotor structure is adopted, the cogging torque generated when the permanent magnets interact with the stator is large, and the spoke-type permanent magnet motor generates redundant air gap harmonics during operation, resulting in a high torque pulsation output by the spoke-type permanent magnet motor.

Utility Model Content

The utility model aims to solve one of the technical problems in the related art at least to a certain extent.

To this end, an embodiment of the utility model provides a rotor, which, when applied to a spoke-type permanent magnet motor, can reduce the cogging torque and air gap harmonics of the spoke-type permanent magnet motor, thereby weakening the torque pulsation output by the spoke-type permanent magnet motor.

The rotor of an embodiment of the utility model includes a rotor core and permanent magnets, and the permanent magnets and the rotor core are alternately arranged in sequence along the circumference of the rotor; the rotor core includes a core body and auxiliary salient poles, and the auxiliary salient poles are arranged on the outside of the core body, and the radial size of the auxiliary salient poles first increases and then decreases along the circumference of the rotor, and the outer contour surface of the auxiliary salient poles extends to the outer circumferential surface of the core body at both ends of the circumference of the rotor; the projection of the outer contour surface of the auxiliary salient pole on the end surface of the rotor forms a contour line, and the contour line is an inverse cosine curve.

In some embodiments, the auxiliary salient poles are symmetrically arranged along the circumference of the rotor.

In some embodiments, the plurality of auxiliary salient poles are centrally symmetrically arranged along the circumference of the rotor.

In some embodiments, the auxiliary salient pole is integrally formed with the core body.

In some embodiments, the permanent magnet is bonded and fixed to the rotor core.

In some embodiments, a maximum dimension of the auxiliary salient pole in the radial direction of the rotor is 1 mm-2 mm.

The permanent magnet motor of the embodiment of the utility model comprises a stator and a rotor, wherein the rotor is the rotor described in any one of the above embodiments, and the rotor is rotatably disposed in the stator, and an air gap is formed between the rotor and the stator.

In some embodiments, the spoke-type permanent magnet motor further includes a connecting member and a rotating shaft, wherein the connecting member is made of a non-magnetic material and is passed through the rotor; the rotating shaft is passed through the connecting member, and the rotating shaft and the rotor are interconnected via the connecting member.

In some embodiments, a first clamping portion is provided on the rotor, and a second clamping portion is provided on the connecting member, and the second clamping portion is engaged with the first clamping portion to connect the connecting member and the rotor.

In some embodiments, the first clamping portion corresponds one-to-one to the rotor core, and the second clamping portion corresponds one-to-one to the first clamping portion.

The rotor of the embodiment of the utility model is provided with an auxiliary salient pole on the outer side of the core body, and the contour line formed by the projection of the outer contour surface of the auxiliary salient pole on the end surface of the rotor is an inverse cosine curve. When the rotor is used in a spoke-type permanent magnet motor, the air gap formed between the rotor and the stator is unevenly distributed along the circumference of the rotor. Compared with the air gap uniformly distributed along the circumference of the rotor in the related art, not only the tooth slot torque can be reduced, but also the air gap harmonics between the rotor and the stator can be reduced, thereby weakening the torque pulsation output by the spoke-type permanent magnet motor.

Therefore, when the rotor of the embodiment of the utility model is used in a spoke-type permanent magnet motor, the torque pulsation output by the spoke-type permanent magnet motor can be weakened.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of a rotor according to an embodiment of the present invention.

FIG. 2 is a schematic structural diagram of a rotor core of a rotor according to an embodiment of the present invention.

FIG3 is a schematic structural diagram of a spoke-type permanent magnet motor according to an embodiment of the present utility model.

FIG. 4 is a partial stereoscopic view of a spoke-type permanent magnet motor according to an embodiment of the present invention.

Reference numerals: 100, spoke-type permanent magnet motor;

10. rotor; 1. rotor core; 11. core body; 12. auxiliary salient pole; 121. contour line; 13. first clamping part; 2. permanent magnet;

20. stator; 201. air gap;

30. Connecting piece; 301. Second clamping portion;

40. Rotating axis.

Detailed ways

The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but cannot be understood as limiting the present invention.

As shown in Figures 1 and 2, the rotor 10 of the embodiment of the utility model includes a rotor core 1 and permanent magnets 2, and the permanent magnets 2 and the rotor core 1 are alternately arranged in sequence along the circumference of the rotor 10; the rotor core 1 includes a core body 11 and an auxiliary salient pole 12, and the auxiliary salient pole 12 is arranged on the outside of the core body 11. The radial size of the auxiliary salient pole 12 in the rotor 10 first increases and then decreases along the circumference of the rotor 10, and the outer contour surface of the auxiliary salient pole 12 extends to the outer peripheral surface of the core body 11 at both ends of the circumference of the rotor 10; the projection of the outer contour surface of the auxiliary salient pole 12 on the end surface of the rotor 10 forms a contour line 121, and the contour line 121 is an inverse cosine curve.

The rotor 10 of the embodiment of the utility model has an auxiliary salient pole 12 arranged on the outer side of the core body 11, and the contour line 121 formed by the projection of the outer contour surface of the auxiliary salient pole 12 on the end surface of the rotor 10 is an inverse cosine curve. When the rotor 10 is used in the spoke-type permanent magnet motor 100, the air gap formed between the rotor 10 and the stator 20 is unevenly distributed along the circumference of the rotor 10. Compared with the air gap uniformly distributed along the circumference of the rotor 10 in the related art, not only the cogging torque can be reduced, but also the air gap harmonics between the rotor 10 and the stator 20 can be reduced, thereby weakening the torque pulsation output by the spoke-type permanent magnet motor 100.

Optionally, as shown in Figure 1, eight rotor cores 1 and eight permanent magnets 2 are respectively provided, and the eight permanent magnets 2 and the eight rotor cores 1 are alternately arranged in sequence along the circumferential direction of the rotor 10, one permanent magnet 2 is provided between every two adjacent rotor cores 1, and one rotor core 1 is also provided between every two adjacent permanent magnets 2.

It can be understood that, as shown in Figure 2, the side of the auxiliary salient pole 12 close to the core body 11 is its inner contour surface, and the inner contour surface of the auxiliary salient pole 12 coincides with the outer peripheral surface of the core body 11; the radial size of the auxiliary salient pole 12 in the rotor 10 refers to: the distance between the two intersection points formed by a straight line extending along the radial direction of the rotor 10 and the inner contour surface and the outer contour surface of the auxiliary salient pole 12.

It can be understood that the outer peripheral surfaces of the multiple core bodies 11 are all located on the same cylindrical surface, and the side of the permanent magnet 2 away from the axis of the rotor 10 is located within the cylindrical surface. Therefore, the outer contour of the rotor 10 is concave at the position corresponding to the permanent magnet 2, and is convex at the position corresponding to the auxiliary salient pole 12.

In some embodiments, the auxiliary salient poles 12 are symmetrically arranged along the circumference of the rotor 10 .

By arranging the auxiliary salient poles 12 symmetrically along the circumference of the rotor 10 , the overall symmetry of the rotor 10 can be improved, and the stability of the rotor 10 can be higher, thereby weakening the torque pulsation output by the spoke-type permanent magnet motor 100 .

In some embodiments, the plurality of auxiliary salient poles 12 are centrally symmetrically arranged along the circumference of the rotor 10 .

By arranging the plurality of auxiliary salient poles 12 in a centrally symmetrical manner, the overall symmetry of the rotor 10 can be further improved, and the rotor 10 can run more stably, thereby weakening the torque pulsation output by the spoke-type permanent magnet motor 100 .

In some embodiments, the auxiliary salient pole 12 is integrally formed with the core body 11 .

By integrally forming the auxiliary salient pole 12 and the core body 11 , production and manufacturing are more convenient, and the strength of the formed rotor core 1 is also higher.

Optionally, the core body 11 and the auxiliary salient pole 12 are made of silicon steel.

In some embodiments, the permanent magnet 2 is bonded and fixed to the rotor core 1 .

The permanent magnet 2 and the rotor core 1 are fixed to each other by bonding, so that the assembly process of the permanent magnet 2 and the rotor core 1 is simpler and the production efficiency is higher.

Optionally, the glue used to bond the permanent magnet 2 to the rotor core 1 is made of a non-magnetic material.

In some embodiments, the maximum dimension of the auxiliary salient pole 12 in the radial direction of the rotor 10 is 1 mm-2 mm.

The setting of the auxiliary salient pole 12 weakens the torque pulsation output by the spoke-type permanent magnet motor 100 and causes the output torque of the spoke-type permanent magnet motor 100 to decrease; by setting the maximum size of the auxiliary salient pole 12 in the radial direction of the rotor 10 to the above range, the output torque and torque pulsation of the spoke-type permanent magnet motor 100 can be better balanced, thereby reducing the influence of the setting of the auxiliary salient pole 12 on the output torque of the spoke-type permanent magnet motor 100.

It can be understood that since the radial size of the auxiliary salient pole 12 in the rotor 10 first increases and then decreases along the circumferential direction of the rotor 10, and the auxiliary salient pole 12 is an axisymmetric structure, the maximum radial size of the auxiliary salient pole 12 in the rotor 10 is: the distance between the symmetry axis of the auxiliary salient pole 12 and the two intersection points formed by the inner contour surface and the outer contour surface of the auxiliary salient pole 12.

Preferably, the maximum dimension of the auxiliary salient pole 12 in the radial direction of the rotor 10 is set to 1.36 mm.

As shown in FIG. 3 , the spoke-type permanent magnet motor 100 of the embodiment of the utility model comprises a stator 20 and a rotor 10 . The rotor 10 is the rotor 10 of any of the above embodiments. The rotor 10 is rotatably disposed in the stator 20 , and an air gap 201 is formed between the rotor 10 and the stator 20 .

The air gap 201 is formed between the rotor 10 and the stator 20. Since the auxiliary salient pole 12 is convex outside the core body 11, the length of the air gap 201 between the outer contour surface of the auxiliary salient pole 12 and the inner circumference of the stator 20 is small, and the air gap 201 is the first air gap. The length of the air gap 201 between the side of the permanent magnet 2 away from the axis of the rotor 10 and the inner circumference of the stator 20 is large, and the air gap 201 is the second air gap. The first air gap and the second air gap are alternately arranged in sequence along the circumference of the rotor 10, so that the air gap 201 is unevenly distributed along the circumference of the rotor 10, which can reduce the cogging torque of the spoke permanent magnet motor 100, and at the same time reduce the air gap harmonics between the rotor 10 and the stator 20, thereby weakening the torque pulsation output by the spoke permanent magnet motor 100. Among them, the length of the air gap 201 refers to the radial dimension of the air gap 201 along the rotor 10.

In addition, the contour line 121 formed by the projection of the outer contour surface of the auxiliary salient pole 12 on the end surface of the rotor 10 is an inverse cosine curve, which can further reduce the cogging torque and air gap harmonics of the spoke-type permanent magnet motor 100, thereby further weakening the torque pulsation output by the spoke-type permanent magnet motor 100.

In some embodiments, as shown in FIG. 4 , the spoke-type permanent magnet motor 100 further includes a connector 30 and a rotating shaft 40 . The connector 30 is made of a non-magnetic material and is passed through the rotor 10 . The rotating shaft 40 is passed through the connector 30 , and the rotating shaft 40 and the rotor 10 are connected to each other through the connector 30 .

The shaft 40 and the rotor 10 are separated by the connecting member 30 to reduce the probability of magnetization of the shaft 40 due to magnetic leakage at one end of the permanent magnet 2 close to the axis of the rotor 10, thereby improving the operating stability of the spoke-type permanent magnet motor 100.

Optionally, the non-magnetic conductive material used to manufacture the connecting member 30 may be insulating bakelite.

It is understandable that, in order to facilitate the connection member 30 to cooperate with the rotor 10 and the rotating shaft 40, the connection member 30 needs to be configured as a cylinder, and the rotor 10, the connection member 30 and the rotating shaft 40 are coaxially arranged.

It is understandable that the rotating shaft 40 and the connecting member 30 can be connected by a key so that the rotating shaft 40 and the connecting member 30 can rotate synchronously.

In some embodiments, the rotor 10 is provided with a first clamping portion 13 , and the connector 30 is provided with a second clamping portion 301 . The second clamping portion 301 is engaged with the first clamping portion 13 to connect the connector 30 and the rotor 10 .

The connecting member 30 and the rotor 10 are connected to each other by means of a snap fit, which has lower cost, lower assembly difficulty and higher production efficiency than welding or bolt connection.

Optionally, as shown in Figure 4, the inner circumference of the rotor 10 is provided with a snap-fit piece, which forms a first snap-fit portion 13; the outer circumference of the connecting piece 30 is provided with a slot, which forms a second snap-fit portion 301, and the snap-fit piece is snap-fitted in the slot to achieve connection between the rotor 10 and the connecting piece 30.

Optionally, the clamp is in the shape of an elongated strip and extends along the axial direction of the rotor 10, and the two end surfaces of the clamp along the axial direction of the rotor 10 are respectively flush with the two end surfaces of the rotor 10 along its axial direction; the circumferential dimension of the clamp along the rotor 10 is its width, and the width of the clamp on the side close to the axis of the rotor 10 is greater than the width of the clamp on the side away from the axis of the rotor 10, so as to reduce the probability of the rotor core 1 and the connector 30 loosening along the radial direction of the rotor 10.

It can be understood that in order to limit the relative movement of the rotor 10 and the connecting member 30 along their axial direction, the first clamping portion 13 and the second clamping portion 301 can be bonded, and/or the relative movement of the rotor 10 and the connecting member 30 can be limited by other related structures of the spoke-type permanent magnet motor 100.

In some embodiments, the first clamping portion 13 corresponds to the rotor core 1 in a one-to-one manner, and the second clamping portion 301 corresponds to the first clamping portion 13 in a one-to-one manner.

A plurality of rotor cores 1 are evenly arranged along the circumference of the rotor 10, and a plurality of first clamping portions 13 and second clamping portions 301 are also arranged along the circumference of the rotor 10. A plurality of connection points are formed between the rotor 10 and the connecting member 30 along the circumference of the rotor 10, thereby improving the stability of the connection between the rotor 10 and the connecting member 30.

Optionally, the clamping piece is formed integrally with the rotor core 1 .

Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are illustrative and cannot be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments made by a person of ordinary skill in the art are all within the scope of protection of the present invention.

Claims (10)

1. A rotor (10), characterized by comprising:

A rotor core (1), and

Permanent magnets (2), the permanent magnets (2) and the rotor core (1) being alternately arranged in sequence along the circumferential direction of the rotor (10);

The rotor core (1) comprises a core body (11) and auxiliary salient poles (12), wherein the auxiliary salient poles (12) are arranged on the outer side of the core body (11), the size of the auxiliary salient poles (12) in the radial direction of the rotor (10) is increased and then reduced along the circumferential direction of the rotor (10), and the outer contour surfaces of the auxiliary salient poles (12) extend to the outer circumferential surface of the core body (11) at two ends of the circumferential direction of the rotor (10);

a projection of the outer contour surface of the auxiliary salient pole (12) on the end surface of the rotor (10) forms a contour line (121), and the contour line (121) is an inverse cosine curve.

2. The rotor (10) according to claim 1, wherein the auxiliary salient poles (12) are symmetrically arranged along a circumferential direction of the rotor (10).

3. The rotor (10) according to claim 1, wherein a plurality of the auxiliary salient poles (12) are arranged in central symmetry along a circumferential direction of the rotor (10).

4. The rotor (10) according to claim 1, wherein the auxiliary salient poles (12) are integrally formed with the core body (11).

5. The rotor (10) according to claim 1, characterized in that the permanent magnets (2) are adhesively fixed to the rotor core (1).

6. The rotor (10) according to claim 1, wherein a maximum dimension of the auxiliary salient pole (12) in a radial direction of the rotor (10) is 1mm to 2mm.

7. A spoke type permanent magnet motor (100), characterized by comprising:

a stator (20); and

A rotor (10), the rotor (10) being a rotor (10) according to any one of claims 1-6, the rotor (10) being rotatably arranged in the stator (20), an air gap (201) being formed between the rotor (10) and the stator (20).

8. The spoke type permanent magnet motor (100) according to claim 7, wherein the spoke type permanent magnet motor (100) further comprises:

The connecting piece (30), the connecting piece (30) is made of non-magnetic conduction material, and the connecting piece (30) penetrates through the rotor (10);

The rotating shaft (40) is arranged on the connecting piece (30) in a penetrating mode, and the rotating shaft (40) and the rotor (10) are connected with each other through the connecting piece (30).

9. The spoke type permanent magnet motor (100) according to claim 8, wherein a first clamping portion (13) is arranged on the rotor (10), a second clamping portion (301) is arranged on the connecting piece (30), and the second clamping portion (301) is matched with the first clamping portion (13) in a clamping manner, so that the connecting piece (30) is connected with the rotor (10).

10. The spoke type permanent magnet motor (100) according to claim 9, wherein the first clamping portions (13) are in one-to-one correspondence with the rotor core (1), and the second clamping portions (301) are in one-to-one correspondence with the first clamping portions (13).