CN220915020U - Permanent magnet for motor rotor, motor rotor and motor - Google Patents

Abstract

The utility model provides a permanent magnet for a motor rotor, the motor rotor and a motor, wherein the motor rotor comprises a rotor core and a permanent magnet arranged on the rotor core, and the permanent magnet comprises: an inner side surface for contacting the rotor core; the outer side surface comprises a first surface and a second surface which are connected with each other, the first surface is opposite to the inner side surface, and the second surface extends obliquely from one end close to the first surface to one end far away from the first surface towards the direction of the inner side surface.

Description

Permanent magnet for motor rotor, motor rotor and motor

Technical Field

The application relates to the field of motors, in particular to a permanent magnet for a motor rotor, the motor rotor and a motor.

Background

In the related art, the permanent magnet of the motor rotor is generally rectangular, and the shape of the permanent magnet of the motor rotor has a certain influence on the performance of the motor, such as power density, harmonic content and the like, so how to improve the shape of the permanent magnet becomes a problem to be solved at present.

Disclosure of utility model

The present utility model aims to solve at least one of the technical problems existing in the prior art or related art.

It is therefore an object of the present utility model to provide a permanent magnet for a rotor of an electric machine.

A second object of the present utility model is to provide a rotor assembly.

A third object of the present utility model is to provide an electric machine.

To achieve the above object, a technical solution of a first aspect of the present utility model provides a permanent magnet for a motor rotor, the motor rotor including a rotor core and a permanent magnet mounted on the rotor core, the permanent magnet including: an inner side surface for contacting the rotor core; the outer side surface comprises a first surface and a second surface which are connected with each other, the first surface is opposite to the inner side surface, and the second surface extends obliquely from one end close to the first surface to one end far away from the first surface towards the direction of the inner side surface.

The permanent magnet for a motor rotor provided according to the present utility model is part of a motor rotor. Wherein the motor rotor includes a rotor core and permanent magnets of the present utility model, and the permanent magnets are mounted on the rotor core. Specifically, the permanent magnet includes an inner side surface and an outer side surface that are oppositely disposed, and the inner side surface is a surface that is fixed with the rotor core, for example, when the motor is an inner stator outer rotor, the permanent magnet is fixed on the inner surface of the rotor core, and at this time, a surface disposed close to the inner surface of the rotor core is an inner side surface, and a surface disposed away from the inner surface of the rotor core is an outer side surface. Meanwhile, the outer side includes a first face and a second face connected to each other, the first face being disposed opposite to the inner side, and generally, the first face being parallel or substantially parallel to the inner side. The second surface is obliquely arranged and is positioned at one end or two ends of the permanent magnet which are circumferentially arranged, and the second surface is obliquely arranged from the center of the permanent magnet to the inner side surfaces of the two ends, namely the distance between the second surface and the inner side surfaces is smaller towards the two ends of the permanent magnet, so that the distance between the second surface and the stator is larger towards the two ends of the permanent magnet, the magnetic characteristic that the magnetic flux density is higher at the center of the permanent magnet and gradually decreases towards the two ends is formed, the magnetic gathering capacity of the permanent magnet can be improved, the amplitude of counter potential fundamental wave is improved, the air gap magnetic field is more sinusoidal, the harmonic content is greatly reduced, the power density of the motor is improved, the harmonic content in the air gap magnetic field is reduced, and the risk of electromagnetic vibration noise of the motor is reduced.

Further, the motor rotor includes a stator assembly, and the outer end surfaces of the plurality of stator teeth of the stator assembly, that is, the end surface near one side of the motor rotor, are inscribed on the same circumference, which is the first circumference. Wherein, the perpendicular distance between first face and the first circumference equals, and the perpendicular distance between second face and the first circumference increases from the one end that is close to first face to the one end that keeps away from first face, and further, this distance is the gradual increase.

Further, the first face is arranged in parallel or quasi-parallel to the inner side, i.e. the distance between the first face and the inner side is substantially equal.

Further, the inner side surface is a first arc-shaped surface, the first surface comprises a second arc-shaped surface, and the second arc-shaped surface is concentric with the first arc-shaped surface. The arrangement is such that the first face and the inner face are substantially uniformly oriented. I.e. the shape of the inner and outer side surfaces is substantially uniform or mutually adapted, with the difference that the outer side surface comprises a second surface arranged obliquely. The permanent magnet is of an arc-shaped structure, so that the inner side face and the first face are arranged to be of an arc-shaped structure, the structure of the permanent magnet is simple, the processing of the permanent magnet is more convenient, and the processing cost can be reduced.

Optionally, the second face comprises a third arcuate face. And/or the second face comprises an inclined plane.

In this technical solution, the second surface may be an arc surface or an inclined plane, or may be a combination surface of an arc surface and an inclined plane, and the specific shape thereof may be set as required, so long as the second surface can be ensured to extend toward the inner side surface beyond the two sides.

Optionally, the first face is located in the middle of the outer side face. The second surface is symmetrically arranged at two ends of the first surface or arranged at one side of the first surface.

In this technical scheme, the second face is located the middle part of lateral surface, and the second face is located the marginal portion of permanent magnet, and wherein, the both ends that the permanent magnet set up along circumference all can inwards extend to form the second face of symmetry setting, also can only one side extend, and the opposite side normally sets up, and at this moment, can form unilateral second face. Optimally, the second surface is symmetrically arranged at two ends of the first surface along the circumferential direction, so that the permanent magnets can form a symmetrical structure, the permanent magnets can be better processed, the magnetic field force of the permanent magnets can be more balanced, and the running stability of the rotor can be improved.

Optionally, the second face comprises a plurality of interconnected sub-faces, the radii of curvature of the plurality of sub-faces increasing from an end proximal to the first face to an end distal from the first face. I.e. from the centre of the permanent magnet to the ends of the permanent magnet.

In this technical solution, the second faces of the two ends of the outer side face arranged along the circumferential direction may be single faces or may be composed of a plurality of faces together, and optimally, the second faces include a plurality of sub-faces with different curvature radii, so that the distance between the second faces and the inner side face is larger as the heterodyne distance is increased. Specifically, for example, the second surface may be a second arc surface, or the second surface may be formed by a section of inclined surface and a section of arc surface together.

Optionally, the first surface includes a second arc surface, and a central angle of an arc where the second arc surface is located is A1, where 0 < A1/(360 °/(2P)) < 0.5, and P represents a pole pair number of the motor.

In this technical scheme, when first face includes the second arcwall face, the length of second arcwall face can not overlength, otherwise can lead to the effect ratio of second face weak. And the central angle A1 of the arc where the second arc-shaped surface is located satisfies the formula: 0 < A1/(360 °/(2P)) < 0.5, the length of the second arcuate surface can be made relatively moderate.

Alternatively, the permanent magnets are arranged axisymmetrically. Further, an included angle between the magnetic domain orientation of the permanent magnet and the symmetry axis of the permanent magnet is alpha, wherein alpha is larger than 0 degrees and smaller than or equal to 45 degrees, namely the maximum angle of alpha can reach 45 degrees. That is, the maximum included angle alpha 1 is greater than or equal to 30 degrees and less than or equal to 45 degrees. In the prior art, the intersection points of different magnetic domain orientations are generally located at the center of the motor and are far away from the permanent magnets. Compared with the prior art, the included angle alpha can reach 45 degrees, and the degree of the included angle is improved, so that the intersection points of different magnetic domain orientations are relatively close to the permanent magnet. Therefore, the magnetic gathering capability of the permanent magnet can be improved, the amplitude of the counter potential fundamental wave is improved, the air gap magnetic field is sinusoidal, the harmonic content is greatly reduced, the power density of the motor is improved, the harmonic content in the air gap magnetic field is reduced, and the risk of electromagnetic vibration noise of the motor is reduced.

Alternatively, the number of magnetic domain orientations of the permanent magnet is plural, and the included angle between the plurality of magnetic domain orientations of each permanent magnet and the symmetry axis (i.e., the central axis of the permanent magnet) gradually increases from a position close to the symmetry axis to a position away from the symmetry axis. The permanent magnet magnetic flux-gathering capacity can be improved, the back electromotive force fundamental wave amplitude is improved, the air gap magnetic field is sinusoidal, the harmonic content is greatly reduced, the power density of the motor is improved, the harmonic content in the air gap magnetic field is reduced, and the risk of electromagnetic vibration noise of the motor is reduced.

Further, the permanent magnets are arranged in an axisymmetric manner, the magnetic domain orientations of the permanent magnets are multiple, and the magnetic domain orientations of the permanent magnets intersect at a point on the symmetry axis of the permanent magnets. Specifically, for example, the material or structure of the permanent magnet may be appropriately set so that different magnetic domain orientations intersect at one point. On the contrary, the different magnetic domain orientations of the permanent magnets can be arranged in parallel without intersecting at one point. The magnetic domain orientation of the motor is intersected at one point, so that the magnetic gathering capability of the permanent magnet can be improved, the amplitude of a counter potential fundamental wave is improved, the air gap magnetic field is sinusoidal, the harmonic content is greatly reduced, the power density of the motor is improved, the harmonic content in the air gap magnetic field is reduced, and the risk of electromagnetic vibration noise of the motor is reduced.

The technical scheme of the first aspect of the utility model provides a motor rotor, which comprises the permanent magnet provided by any one of the technical scheme of the first aspect.

In view of the fact that the motor rotor provided by the utility model comprises the permanent magnets provided by any one of the technical schemes of the first aspect, the motor rotor has all the beneficial effects of the permanent magnets.

Further, the motor rotor further includes: a rotor core; one or more permanent magnets are arranged on the inner side of the rotor core, and the inner side surface of each permanent magnet is the surface of the permanent magnet close to the rotor core.

In this solution, one or more permanent magnets are mounted inside the rotor core, so that the stator assembly is located inside the motor rotor, thus making it possible to construct a motor with an inner stator and an outer rotor.

Further, a plurality of permanent magnets are arranged along the circumferential direction of the rotor core, and the magnetization directions of two adjacent magnetic poles are opposite. The outer side of the permanent magnet is the side close to the air gap, the outer side is distributed into a plurality of sections of cambered surfaces, the first section of cambered surface is positioned at the center of the permanent magnet, the other sections of cambered surfaces are symmetrically distributed along the first section of cambered surface, the distance between the first section of cambered surface and the cylindrical surface formed by the outer diameter of the stator core is shortest, the distance between the other sections of cambered surfaces and the cylindrical surface formed by the outer diameter of the stator core is gradually increased, namely, the farther the distance between the plurality of sections of cambered surfaces and the center line of the permanent magnet is, the larger the distance between the multi sections of cambered surfaces and the cylindrical surface formed by the outer diameter of the rotor core is.

Further, the outer surface of the permanent magnet and the inner surface of the rotor core are fixed together through plastic wrapping, and the permanent magnets are all arranged on the inner surface of the rotor core.

The technical scheme of the first aspect of the utility model provides a motor, which comprises the permanent magnet provided by any one of the technical scheme of the first aspect, or the motor rotor provided by any one of the technical scheme of the second aspect.

In view of the motor provided by the utility model, the motor comprises the permanent magnet provided by any one of the technical schemes in the first aspect or the motor rotor provided by any one of the technical schemes in the second aspect, therefore, the motor has all the beneficial effects of the permanent magnet provided by any one of the technical schemes in the first aspect or all the beneficial effects of the motor rotor provided by any one of the technical schemes in the second aspect.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows, or may be learned by practice of the utility model.

Drawings

The foregoing and/or additional aspects and advantages of the utility model will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

fig. 1 is a schematic structural view of a permanent magnet according to an embodiment of the present utility model;

FIG. 2 is a schematic illustration of the configuration of a motor rotor and stator assembly mating provided by an embodiment of the present utility model;

FIG. 3 is a schematic illustration of the magnetic domain orientation of two adjacently disposed permanent magnets provided by an embodiment of the present utility model;

FIG. 4 is a schematic view of a portion of a motor rotor according to an embodiment of the present utility model;

fig. 5 is a schematic view showing a partial structure of a motor rotor according to another embodiment of the present utility model;

fig. 6 is a schematic view of a structure of a motor rotor provided by another embodiment of the present utility model;

FIG. 7 shows a comparison of the back emf harmonic content of the motor of the present application and a prior art motor;

fig. 8 shows a counter potential contrast diagram of the motor of the present application and the existing motor.

Wherein, the correspondence between the reference numerals and the component names in fig. 1 to 6 is:

1 permanent magnet, 12 inner side, 14 outer side, 142 first side, 144 second side, 1442 first sub-side, 1444 second sub-side, 2 rotor core, 3 stator assembly, 4 first circumference.

Detailed Description

In order that the above-recited objects, features and advantages of the present utility model will be more clearly understood, a more particular description of the utility model will be rendered by reference to the appended drawings and appended detailed description. It should be noted that, without conflict, the embodiments of the present utility model and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present utility model, but the present utility model may be practiced in other ways than those described herein, and therefore the scope of the present utility model is not limited to the specific embodiments disclosed below.

As shown in fig. 1 to 6, an embodiment of a first aspect of the present utility model provides a permanent magnet 1 for a motor rotor including a rotor core 2 and a permanent magnet 1 mounted on the rotor core 2, the permanent magnet 1 including: an inner side 12 for contact with the rotor core 2; the outer side surface 14 includes a first surface 142 and a second surface 144 that are connected to each other, the first surface 142 being disposed opposite the inner side surface 12, and the second surface 144 extending obliquely from an end near the first surface 142 to an end far from the first surface 142 in the direction of the inner side surface 12.

The permanent magnet 1 for a motor rotor according to the utility model is provided as part of the motor rotor. Wherein the motor rotor comprises a rotor core 2 and a permanent magnet 1 in the present utility model, and the permanent magnet 1 is mounted on the rotor core 2. Specifically, the permanent magnet 1 includes an inner side 12 and an outer side 14 that are disposed opposite to each other, and the inner side 12 is a surface fixed to the rotor core 2, for example, when the motor is an inner stator outer rotor, the permanent magnet 1 is fixed to the inner surface of the rotor core 2, and at this time, a surface disposed near the inner surface of the rotor core 2 is the inner side 12, and a surface disposed away from the inner surface of the rotor core 2 is the outer side 14. Meanwhile, the outer side 14 includes a first side 142 and a second side 144 that are connected to each other, the first side 142 being disposed opposite the inner side 12, and generally, the first side 142 being parallel or substantially parallel to the inner side 12. The second surface 144 is disposed obliquely, and is located at two ends of the permanent magnet 1 disposed circumferentially, and the second surface 144 is disposed obliquely from the center of the permanent magnet 1 to the inner side 12 toward the two ends, that is, the distance between the second surface 144 and the inner side 12 decreases toward the two ends of the permanent magnet 1, so that the distance (length indicated by double-headed arrow in fig. 5) between the second surface 144 and the stator increases toward the two ends of the permanent magnet 1 disposed circumferentially. According to the structure, through changing the shape of the permanent magnet 1, the magnetic characteristic that the magnetic flux density is high in the center of the permanent magnet 1 and gradually reduces at the two ends nearer to the center can be formed, so that the magnetic focusing capacity of the permanent magnet 1 can be improved, the back electromotive force fundamental wave amplitude is improved, the air gap magnetic field is sinusoidal, the harmonic content is greatly reduced, the power density of the motor is improved, the harmonic content in the air gap magnetic field is reduced, the risk of electromagnetic vibration noise of the motor is reduced, and the performance of the motor is improved as a whole.

As can be seen from fig. 7, the counter potential of the motor of the present application is significantly increased under no load compared with the conventional motor. As can be seen from fig. 8, the back emf harmonic content of the motor of the present application is significantly reduced compared to the prior art motor. The application can ensure that the air gap magnetic field is more sinusoidal on the whole, greatly reduces the harmonic content, not only improves the power density of the motor, but also reduces the harmonic content in the air gap magnetic field and reduces the risk of electromagnetic vibration noise of the motor.

Further, as shown in fig. 4 and 5, the motor rotor includes a stator assembly 3, and the outer end surfaces of the plurality of stator teeth of the stator assembly 3, that is, the end surfaces near one side of the motor rotor are inscribed on the same circumference, which is the first circumference 4. Wherein the vertical distance between the first surface 142 and the first circumference 4 is equal, and the vertical distance between the second surface 144 and the first circumference 4 increases from one end near the first circumference 4 to one end far from the first circumference 4, and further, the distance gradually increases.

Further, as shown in fig. 1, the first surface 142 is disposed parallel or nearly parallel to the inner side 12, that is, the distance between the first surface 142 and the inner side 12 is substantially equal.

Further, as shown in fig. 1, the inner side 12 is a first arcuate surface, and the first surface 142 includes a second arcuate surface concentric with the first arcuate surface. This arrangement allows the first face 142 to be substantially aligned with the interior side 12. That is, the shape of medial side 12 and lateral side 14 are generally uniform, except that lateral side 14 includes a second surface 144 that is obliquely disposed. However, it is common that the permanent magnet 1 has an arc structure, so that the inner side 12 and the first surface 142 are arranged in an arc structure, so that the structure of the permanent magnet 1 is relatively simple, the processing of the permanent magnet 1 is more convenient, and the processing cost can be reduced.

In a particular embodiment, as shown in FIG. 1, the second face 144 includes a third arcuate face and/or an angled planar face.

In this embodiment, the second surface 144 may be an arc surface or an inclined plane, and of course, may be a combination surface of an arc surface and an inclined plane, and the specific shape thereof may be set as required, so long as the second surface 144 can be ensured to extend toward the inner side 12 toward both sides.

In one embodiment, as shown in FIG. 1, first face 142 is located in the middle of lateral side 14; the second faces 144 are symmetrically disposed at both ends of the first face 142 disposed in the circumferential direction. In another embodiment, the second face 144 is disposed at a circumferentially disposed end (not shown in this embodiment) of the first face 142.

In this embodiment, the second surface 144 is located in the middle of the outer side surface 14, and the second surface 144 is located at an edge portion of the permanent magnet 1, wherein both ends of the permanent magnet 1 disposed along the circumferential direction may extend inward to form the second surface 144 disposed symmetrically, or may extend only on one side, and the other side may be disposed normally, and in this case, the second surface 144 may be formed on one side. Optimally, the second surface 144 is symmetrically arranged at two ends of the first surface 142 along the circumferential direction, so that the permanent magnet 1 can form a symmetrical structure, thereby better processing the permanent magnet 1, and more balancing the magnetic field force of the permanent magnet 1, thereby improving the running stability of the rotor,

In one embodiment, as shown in FIG. 1, the second face 144 includes a plurality of interconnected sub-faces having radii of curvature that increase from an end proximal to the first face 142 to an end distal from the first face 142. Specifically, the sub-faces include a first sub-face 1442 and a second sub-face 1444 that are connected to each other.

In this embodiment, the second faces 144 of the two ends of the outer side 14 disposed along the circumferential direction may be formed as a single face or may be formed by a plurality of faces together, and most preferably, the second faces 144 include a plurality of sub-faces with different radii of curvature, so that the further the second faces 144 are from the inner side 12, the greater the heterodyne distance. Specifically, for example, the second surface 144 may be a second arcuate surface, or the second surface 144 may be formed by a section of inclined surface and a section of arcuate surface.

In one embodiment, the first face 142 includes a second arcuate face having an arc with a central angle A1, where 0 < A1/(360 °/(2P)) < 0.5, where P represents the pole pair number of the motor. 2P represents the number of poles of the motor.

In this embodiment, when the first face 142 includes a second arcuate face, the length of the second arcuate face cannot be too long, which would otherwise result in a weaker effect of the second face 144. And the central angle A1 of the arc where the second arc-shaped surface is located satisfies the formula: 0 < A1/(360 °/(2P)) < 0.5, the length of the second arcuate surface can be made relatively moderate.

In a specific embodiment, as shown in fig. 3, the permanent magnets 1 are axisymmetrically arranged, and an included angle between the magnetic domain orientation of the permanent magnet 1 and the symmetry axis of the permanent magnet 1 is a, where a is greater than 0 ° and less than or equal to 45 °, that is, the maximum angle of a can reach 45 °. That is, the maximum included angle alpha 1 is greater than or equal to 30 degrees and less than or equal to 45 degrees. Whereas in the prior art solutions the intersection points of the different domain orientations are typically at the centre of the motor, relatively far from the permanent magnet 1, in the prior art solutions the angle between the different domain orientations and the symmetry axis of the permanent magnet 1 is typically much smaller than 45 °. The included angle alpha can reach 45 degrees, so that the intersection points of different magnetic domain orientations are relatively close to the permanent magnet 1. Therefore, the magnetic focusing capability of the permanent magnet 1 can be improved, the amplitude of the counter potential fundamental wave is improved, the air gap magnetic field is sinusoidal, the harmonic content is greatly reduced, the power density of the motor is improved, the harmonic content in the air gap magnetic field is reduced, and the risk of electromagnetic vibration noise of the motor is reduced.

In a specific embodiment, as shown in fig. 3, the magnetic domain orientations of the permanent magnets 1 have a plurality of magnetic domain orientations, and the included angle between the plurality of magnetic domain orientations of each permanent magnet 1 and the symmetry axis gradually increases from a position close to the symmetry axis to a position far from the symmetry axis. The arrangement can improve the magnetic focusing capability of the permanent magnet 1, improves the amplitude of the counter potential fundamental wave, simultaneously enables the air gap magnetic field to be more sinusoidal, greatly reduces the harmonic content, improves the power density of the motor, reduces the harmonic content in the air gap magnetic field, and reduces the risk of electromagnetic vibration noise of the motor.

Further, as shown in fig. 3, the permanent magnet 1 is axisymmetrically arranged, the magnetic domain orientation of the permanent magnet 1 has a plurality, and the plurality of magnetic domain orientations of the permanent magnet 1 intersect at a point on the symmetry axis of the permanent magnet 1. Specifically, for example, the material or structure of the permanent magnet 1 may be appropriately set so that different magnetic domain orientations intersect at one point. On the contrary, the different magnetic domain orientations of the permanent magnet 1 may be arranged parallel to each other without intersecting at a point. The magnetic domain orientations of the different magnetic domains are intersected at one point, so that the magnetic gathering capability of the permanent magnet 1 can be improved, the back electromotive force fundamental wave amplitude is improved, the air gap magnetic field is sinusoidal, the harmonic content is greatly reduced, the power density of the motor is improved, the harmonic content in the air gap magnetic field is reduced, and the risk of electromagnetic vibration noise of the motor is reduced.

As shown in fig. 2, 5 and 6, an embodiment of the first aspect of the present utility model provides a motor rotor comprising the permanent magnet 1 provided by any of the embodiments of the first aspect.

In view of the fact that the motor rotor provided by the utility model comprises the permanent magnets 1 provided by any embodiment of the first aspect, the motor rotor has all the beneficial effects of the permanent magnets 1.

Further, as shown in fig. 2, 5 and 6, the motor rotor further includes: a rotor core 2; one or more permanent magnets 1 are mounted on the inner side of the rotor core 2, and the inner side 12 of the permanent magnet 1 is the side of the permanent magnet 1 close to the rotor core 2.

In this embodiment, one or more permanent magnets 1 are mounted inside a rotor core 2 such that a stator assembly 3 is located inside a motor rotor, thereby making it possible to construct a motor with an inner stator outer rotor.

Further, as shown in fig. 3, a plurality of permanent magnets 1 are arranged along the circumferential direction of the rotor core 2, and the magnetization directions of adjacent two magnetic poles are opposite. Wherein in fig. 3, the dashed lines with arrows indicate the magnetic domain orientations. Whereas the arrow points indicate the magnetization direction, it can be seen from fig. 3 that the arrow points of the two permanent magnets 1 are not identical, so that the magnetization direction is not identical.

Further, the outer side 14 of the permanent magnet 1 is the side close to the air gap, and is distributed into a plurality of sections of cambered surfaces, the first section of cambered surface is located at the center of the permanent magnet 1, the other sections of cambered surfaces are symmetrically distributed along the first section of cambered surface, the distance between the first section of cambered surface and the cylindrical surface formed by the outer diameter of the stator core is shortest, the distance between the other sections of cambered surfaces and the cylindrical surface formed by the outer diameter of the stator core is gradually increased, namely, the farther the distance between the plurality of sections of cambered surfaces and the central line of the permanent magnet 1 is, the larger the distance between the plurality of sections of cambered surfaces and the cylindrical surface formed by the outer diameter of the rotor core 2 is.

Further, the outer surface of the permanent magnet 1 and the inner surface of the rotor core 2 are fixed together through plastic coating, and the permanent magnets 1 are all arranged on the inner surface of the rotor core 2.

An embodiment of the first aspect of the present utility model provides an electric machine (not shown in the figures) comprising the permanent magnet 1 provided by any embodiment of the first aspect, or the electric machine rotor provided by any embodiment of the second aspect.

In view of the motor provided by the utility model, which comprises the permanent magnet 1 provided by any embodiment of the first aspect or the motor rotor provided by any embodiment of the second aspect, the motor has all the advantages of the permanent magnet 1 provided by any embodiment of the first aspect or all the advantages of the motor rotor provided by any embodiment of the second aspect.

In the description of the present specification, the terms "connected," "mounted," "secured," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a removable connection, or an integral connection; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, the terms "one embodiment," "some embodiments," "particular embodiments," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above is only a preferred embodiment of the present utility model, and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. A permanent magnet for a motor rotor, the motor rotor comprising a rotor core and the permanent magnet mounted on the rotor core, the permanent magnet comprising:

an inner side surface for contacting the rotor core;

The outer side surface comprises a first surface and a second surface which are connected with each other, the first surface is opposite to the inner side surface, and the second surface obliquely extends from one end close to the first surface to one end far away from the first surface to the direction of the inner side surface.

2. A permanent magnet for a rotor of an electric machine according to claim 1, characterized in that,

The inner side is a first arc-shaped surface, the first surface comprises a second arc-shaped surface, and the second arc-shaped surface is concentric with the first arc-shaped surface.

3. A permanent magnet for a rotor of an electric machine according to claim 1, characterized in that,

The second face includes a third arcuate face.

4. A permanent magnet for a rotor of an electric machine according to claim 1, characterized in that,

The second face includes an inclined plane.

5. A permanent magnet for a rotor of an electric machine according to claim 1, characterized in that,

The first surface is positioned in the middle of the outer side surface;

The second surface is symmetrically arranged at two ends of the first surface which are arranged along the circumferential direction, or the second surface is arranged at one end of the first surface which is arranged along the circumferential direction.

6. A permanent magnet for a rotor of an electric machine according to claim 1, characterized in that,

The second face includes a plurality of interconnected sub-faces, a plurality of which have radii of curvature that increase from an end proximate to the first face to an end distal from the first face.

7. A permanent magnet for a rotor of an electric machine according to any one of claims 1 to 6, characterized in that the inner side is a first arc-shaped surface, the central angle of the arc in which the first arc-shaped surface is located being A1, wherein 0 < A1/(360/(2P)) < 0.5, P representing the pole pair number of the electric machine.

8. An electric motor rotor, comprising: one or more permanent magnets according to any one of claims 1 to 7.

9. The electric machine rotor as recited in claim 8, further comprising:

a rotor core;

One or more permanent magnets are arranged on the inner side of the rotor core, and the inner side surface of each permanent magnet is the surface of each permanent magnet close to the rotor core.

10. An electric machine, comprising:

One or more permanent magnets for a rotor of an electric machine according to any one of claims 1 to 7; or (b)

An electric machine rotor as claimed in claim 8 or 9.