CN216564692U

CN216564692U - Motor rotor and motor

Info

Publication number: CN216564692U
Application number: CN202122845977.1U
Authority: CN
Inventors: 向星; 王晓明; 钱慧杰; 殷召凯; 吴娇
Original assignee: SAIC General Motors Corp Ltd; Pan Asia Technical Automotive Center Co Ltd
Current assignee: SAIC General Motors Corp Ltd; Pan Asia Technical Automotive Center Co Ltd
Priority date: 2021-11-19
Filing date: 2021-11-19
Publication date: 2022-05-17
Anticipated expiration: 2031-11-19

Abstract

The utility model relates to a motor rotor and a motor. The electric motor rotor has the iron core be provided with a plurality of magnetic pole district on the iron core, a plurality of magnetic pole district arrange along the circumferencial direction of iron core evenly, and every magnetic pole district is including first magnetic pole pair and second magnetic pole pair, first magnetic pole pair compare in the second magnetic pole pair is closer to the outer circumference of iron core, first magnetic pole pair and second magnetic pole pair arrange and have two tip magnet steels respectively about the central axis symmetry of the magnetic pole district that assigns respectively, wherein, arrange the same magnetic pole district symmetrically in the diameter direction of iron core, wherein one or more magnetic pole district is different with adjacent magnetic pole district in the angle aspect between two tip magnet steels of second magnetic pole pair. The motor rotor according to the present application can reduce higher order harmonics of radial electromagnetic force and thereby improve motor vibration and noise problems through asymmetry of adjacent pole regions.

Description

Motor rotor and motor

Technical Field

The utility model relates to a motor rotor and a motor having such a motor rotor.

Background

In a pure electric drive system and a hybrid drive system, a drive motor plays a vital role in the quality of the drive system and the duration of the endurance mileage. Permanent magnet synchronous motors, especially interior permanent magnet synchronous motors, are commonly used as main drive motors due to their wide speed regulation range, large reluctance torque, high low-speed zone efficiency, and good field weakening performance.

However, the interior permanent magnet synchronous motor generates tangential torque ripple during application, and in addition, high-order harmonics may be generated by radial electromagnetic force acting on the stator core, which may finally cause vibration and noise of an automobile, i.e., NVH problem. The torque ripple referred to herein can also be caused by the structure of the motor itself without thought. For example, interior permanent magnet machines are typically designed to be relatively compact and have a high air gap flux density due to space and cost constraints in an automobile.

SUMMERY OF THE UTILITY MODEL

The object of the utility model is to provide an improved topology for an electric machine, in particular for a rotor of an electric machine, which improves the problems of vibration and noise of the electric machine.

A rotor for an electric machine according to one aspect of the present invention has a core on which a plurality of magnetic pole regions are provided, the plurality of magnetic pole regions being arranged uniformly in a circumferential direction of the core, each magnetic pole region including a first magnetic pole pair and a second magnetic pole pair, the first magnetic pole pair being closer to an outer circumference of the core than the second magnetic pole pair, the first magnetic pole pair and the second magnetic pole pair being arranged symmetrically with respect to a central axis of the associated magnetic pole region and having two end magnetic steels, respectively, wherein identical magnetic pole regions are arranged symmetrically in a diametrical direction of the core, wherein one or more magnetic pole regions differ from adjacent magnetic pole regions in an angle between the two end magnetic steels of the second magnetic pole pair.

According to one aspect of the present invention, there is provided a rotor for an electric machine, wherein one or more of the pole regions differs from an adjacent pole region in a pole arc coefficient of the second pole pair.

According to one aspect of the utility model, a rotor for an electrical machine is proposed, in which one or more auxiliary grooves are provided in the region enclosed by the first pole pair and the outer circumference of the core, said auxiliary grooves being arranged symmetrically with respect to the central axis of the associated pole zone.

According to one aspect of the present invention, a rotor for an electric machine is provided with auxiliary slots of different shapes in adjacent pole regions.

According to one aspect of the present invention, a rotor for an electric machine is provided with a different number of auxiliary slots in adjacent pole regions.

According to one aspect of the present invention, a rotor of an electric machine is proposed, in which a center magnetic steel is arranged between the two end magnetic steels.

According to one aspect of the utility model, a motor rotor is provided, in which a weight-reduction hole is provided in each pole region for reducing the moment of inertia of the motor rotor.

According to one aspect of the present invention, there is provided a rotor for an electric machine, wherein the first pole pair and the second pole pair are made of neodymium iron boron or ferrite or samarium cobalt material.

According to the rotor of the motor, the iron core is formed by pressing multiple layers of punching sheets, and the magnetic pole regions are arranged on each punching sheet.

The motor rotor according to the present application can reduce higher order harmonics of radial electromagnetic force and thereby improve motor vibration and noise problems through asymmetry of adjacent pole regions.

According to a further aspect of the utility model, an electric machine is proposed having a stator and such a machine rotor.

Drawings

The above and other features of the present invention will become apparent with reference to the accompanying drawings, in which:

fig. 1 shows a schematic representation of a rotor of an electrical machine according to the utility model;

fig. 2 shows a part of the rotor of the electrical machine according to fig. 1.

Detailed Description

It is easily understood that according to the technical solution of the present invention, a person skilled in the art can propose various alternative structures and implementation ways without changing the spirit of the present invention. Therefore, the following detailed description and the accompanying drawings are merely illustrative of the technical aspects of the present invention, and should not be construed as all of the present invention or as limitations or limitations on the technical aspects of the present invention.

The terms of orientation of up, down, left, right, front, back, top, bottom, and the like referred to or may be referred to in this specification are defined relative to the configuration shown in the drawings, and are relative terms, and thus may be changed correspondingly according to the position and the use state of the device. Therefore, these and other directional terms should not be construed as limiting terms. Furthermore, the terms "first," "second," "third," and the like are used for descriptive and descriptive purposes only and not for purposes of indication or implication as to the relative importance of the respective components.

Fig. 1 shows a schematic illustration of an electric machine rotor, wherein, for the sake of clarity, further accessories of the electric machine rotor are not shown. The motor rotor has an iron core, which can be formed by pressing multiple layers of stamped sheets, each stamped sheet having the same structure. The core is provided with a through-hole in the middle thereof and is provided with a plurality of pole sections 1 distributed uniformly in the circumferential direction thereof, each of which is configured in a sector shape, for example eight pole sections are provided in fig. 1, each of which is at a 45 ° angle with respect to the center of the core. In other words, when N pole regions are provided, the central angle of each pole region is 360 °/N. For the sake of clarity, only two adjacent pole zones are provided with the reference numeral "1" in the figures. A plurality of pole pairs are arranged in each pole zone, said pole pairs being arranged symmetrically with respect to the center axis of the associated pole zone (said center axis intersecting the center of the core and the pole zones being symmetrical with respect to their center axis). For example, two pole pairs can be provided, which is explained in detail below. For example, it is also possible to provide more than two pole pairs, i.e. it is also possible to provide a middle pole pair.

It should be noted at the outset that the concept of "pole pair" as used herein is not limited to being made up of only two parts, but can be made up of more than two parts.

In the following, a detailed explanation is given in connection with the embodiments shown in fig. 1 and 2. A first pole pair 11 and a second pole pair 12 are arranged in each pole zone 1, wherein the first pole pair 11 is closer to the core outer circumference than the second pole pair 12. Each pole pair comprises a plurality of separate magnetic steels (which can also be referred to as permanent magnets) respectively, which are embedded in the interior of the core. In particular, the first pole pair 11 has a plurality of magnetic steels 111 and the second pole pair 12 has a plurality of magnetic steels 121, in the embodiment shown in the figures, the first and

second pole pairs

11, 12 each have two magnetic steels, which can also be referred to as end magnetic steels.

The magnet 111 of the first pole pair 11 is received and fixed in a magnet slot provided in the core, which is configured to be long relative to the magnet, so that it has a first slot 112 and a second slot 113 at both ends, respectively, which are not intended for receiving the magnet. The first slot 112 is closer to the outer circumference of the core and forms an outer flux barrier bridge therewith. In contrast, the second slot 113 is located between the magnetic steels 111 belonging to the same magnetic pole pair, and the second slot 113 and the adjacent second slot 113 form a stressed magnetic bridge together. In addition, the width of the magnetic steel slot at the section for accommodating the magnetic steel is larger than that at the first slot hole and the second slot hole, so that the magnetic steel slot has a stopping effect on the magnetic steel, and the magnetic steel is prevented from moving in the magnetic steel slot. The description herein for the first pole pair applies equally to the second pole pair or an otherwise arranged intermediate pole pair.

It should be noted here that the "first slot" and the "second slot" are based only on their functions and relative positions, and are not limited in number.

According to the utility model, the vibration and noise problems of the motor are alleviated by an asymmetric topology of the motor rotor. This can be achieved by differently arranged adjacent pole zones, but it should be noted that identical pole zones have to be arranged on the diameter of the core, that is to say that the pole zones opposite one another have the same arrangement or structure, in order to ensure a rotational balance of the rotor.

The asymmetry can be achieved by the angles formed by the two end magnets of each pole pair being different from each other in adjacent pole regions. For example, the angle between the two end magnets 121 of the second pole pair 12 in one pole zone is 120 ° and in the adjacent pole zone is 117 °, which improves the tunability of the air gap magnetic density waveform and facilitates the balance between torque ripple and back emf sinusoidality. Alternatively, the difference between adjacent magnetic pole regions can also be achieved by the second magnetic pole pair in adjacent magnetic pole regions having different pole arc coefficients. In this manner, the asymmetry of the second pole pair in adjacent pole regions disperses the harmonics of the radial force and can effectively reduce the dominant orders of vibration noise that contribute to the motor.

It should be noted here that the description of the second pole pair for the purpose of forming a difference between adjacent pole zones applies equally to the first pole pair or the additionally arranged intermediate pole pair.

Optionally, in each pole zone, one or more auxiliary grooves 13 are also arranged in the region between the first pole pair and the outer circumference of the core, which auxiliary grooves are arranged symmetrically with respect to the central axis of the associated pole zone in order to ensure a rotational balance of the motor rotor. Here, the auxiliary groove 13 presses the shaft magnetic circuit of the motor D, Q and thereby changes the torque characteristics of the motor so as to reduce torque ripple.

Alternatively, the above-mentioned difference of adjacent pole zones can be achieved by providing different auxiliary slots, for example different shapes and different numbers of auxiliary slots. As shown in the drawing, only one auxiliary groove 13 is provided in one of the magnetic pole regions, and two auxiliary grooves 13 are provided in the magnetic pole region adjacent thereto. The auxiliary groove 13 can be provided, for example, with a circular, rectangular or polygonal cross section. Here, the number and shape of the auxiliary grooves are changed as needed.

Optionally, in each pole pair, between the two end magnets, there is also a center magnet (not shown), which can be oriented, for example, perpendicular to the center axis of the associated pole zone, and the magnet slot associated with this center magnet forms a stressed magnet bridge on both sides with the adjacent end magnet or the other center magnet.

Further, in order to reduce the moment of inertia of the motor rotor, identically arranged lightening holes 14 are provided in each pole region, which lightening holes can have a polygonal or circular outer shape, which is preferably rounded.

Alternatively, the first and second pole pairs and the intermediate pole pair, if present, can be made of neodymium iron boron or ferrite or samarium cobalt material.

The present application also relates to an electric machine having such a machine rotor, which also has a stator interacting with the rotor, which can have the advantages described above and which is not described in detail here.

It should be understood that all of the above preferred embodiments are exemplary and not restrictive, and that various modifications and changes in the specific embodiments described above, which would occur to persons skilled in the art upon consideration of the above teachings, are intended to be within the scope of the utility model.

Claims

1. Motor rotor having a core on which a plurality of magnetic pole regions are provided, the plurality of magnetic pole regions being uniformly arranged along a circumferential direction of the core, each magnetic pole region including a first magnetic pole pair and a second magnetic pole pair, the first magnetic pole pair being closer to an outer circumference of the core than the second magnetic pole pair, the first magnetic pole pair and the second magnetic pole pair being symmetrically arranged with respect to a central axis of the associated magnetic pole region, respectively, and having two end magnetic steels, respectively, characterized in that identical magnetic pole regions are symmetrically arranged in a diameter direction of the core, wherein one or more magnetic pole regions differ from an adjacent magnetic pole region in an angle between the two end magnetic steels of the second magnetic pole pair.

2. An electric machine rotor as claimed in claim 1, in which one or more of the pole regions differs from an adjacent pole region in the pole arc coefficient of the second pole pair.

3. An electric machine rotor according to claim 1, characterised in that one or more auxiliary slots are provided in the area enclosed by the first pole pair and the outer circumference of the core, the auxiliary slots being arranged symmetrically with respect to the central axis of the associated pole zone.

4. An electric machine rotor as claimed in claim 3, characterised in that differently shaped auxiliary slots are provided in adjacent pole regions.

5. An electric machine rotor as claimed in claim 3, characterised in that a different number of auxiliary slots are provided in adjacent pole regions.

6. An electric machine rotor according to claim 1, characterised in that an intermediate magnetic steel is arranged between the two end magnetic steels.

7. An electric machine rotor as claimed in claim 1, in which a lightening hole is provided in each pole region for reducing the moment of inertia of the electric machine rotor.

8. The electric machine rotor of claim 1, wherein the first and second pole pairs are made of neodymium iron boron or ferrite or samarium cobalt material.

9. An electric machine rotor as claimed in any of claims 1 to 8, characterised in that the core is pressed from a plurality of laminations, on each of which the pole regions are arranged.

10. Electrical machine, characterized by a stator and an electrical machine rotor according to any of claims 1-9.