阅读说明：本技术 一种电机 (Electric machine ) 是由 何章 梁宏常 于 2019-12-17 设计创作，主要内容包括：本发明涉及电机,具体涉及一种电机。包括相互配合的转子和定子,转子包括：转子支架；钕铁硼永磁体,钕铁硼永磁铁周向分布在转子支架上；铁氧体磁铁,铁氧体磁铁覆盖在钕铁硼永磁体的靠近定子的轴向侧面上；极靴,极靴设置在转子支架上,极靴隔开相邻的两个钕铁硼永磁体。在钕铁硼永磁体的轴向侧面设置铁氧体磁铁,使钕铁硼永磁体远离了定子铁芯,钕铁硼永磁体所在位置的气隙磁场相对均匀,从而减少了涡流的产生；此外,靠近电机定子铁芯的位置由铁氧体磁铁替代,铁氧体磁铁具有良好的绝缘性,即使在高频的旋转磁场中也几乎不产生涡流损耗。解决了现有技术中存在的盘式电机的转子在磁场中易产生涡流,导致转子退磁；凸极率低的技术问题。(The invention relates to a motor, in particular to a motor. Including rotor and stator mutually supporting, the rotor includes: a rotor support; the neodymium iron boron permanent magnets are circumferentially distributed on the rotor bracket; the ferrite magnet covers the axial side face, close to the stator, of the neodymium iron boron permanent magnet; and the pole shoes are arranged on the rotor bracket and separate two adjacent neodymium iron boron permanent magnets. The ferrite magnet is arranged on the axial side face of the neodymium iron boron permanent magnet, so that the neodymium iron boron permanent magnet is far away from a stator core, and an air gap magnetic field at the position of the neodymium iron boron permanent magnet is relatively uniform, so that the generation of eddy current is reduced; in addition, the position close to the motor stator core is replaced by a ferrite magnet, and the ferrite magnet has good insulation and hardly generates eddy current loss even in a high-frequency rotating magnetic field. The problem that the rotor of the disc type motor in the prior art is easy to generate eddy current in a magnetic field, so that the rotor is demagnetized is solved; the salient pole rate is low.)

1. An electric machine comprising a rotor (1) and a stator (2) cooperating with each other, characterized in that the rotor (1) comprises:

a rotor support (11);

the neodymium iron boron permanent magnets (12), and the neodymium iron boron permanent magnets (12) are circumferentially distributed on the rotor bracket (11);

a ferrite magnet (13), wherein the ferrite magnet (13) covers the axial side surface of the neodymium iron boron permanent magnet (12) close to the stator (2);

the pole shoes (14), pole shoes (14) set up on rotor support (11), pole shoes (14) separate two adjacent neodymium iron boron permanent magnet (12).

2. An electric machine according to claim 1, characterized in that the neodymium-iron-boron permanent magnets (12) are circumferentially distributed on the same axial side of the rotor support (11), the ferrite magnets (13) covering the axial side of the neodymium-iron-boron permanent magnets (12) remote from the rotor support (11).

3. An electric machine according to claim 2, characterized in that the stator (2) is one, the stator (2) being located axially outside the rotor (1) near the ferrite magnets (13).

4. The motor according to claim 1, wherein mounting holes (111) are distributed in the circumferential direction of the rotor support (11), the neodymium iron boron permanent magnet (12) is embedded in the mounting holes (111), and the ferrite magnets (13) are covered on two axial sides of the neodymium iron boron permanent magnet (12).

5. An electric machine according to claim 4, characterized in that the neodymium-iron-boron permanent magnet (12) is fitted with ferrite magnets (13) on both sides to fill the mounting hole (111).

6. An electric machine according to claim 4, characterized in that the pole shoes (14) are made of magnetically highly conductive soft magnetic material, the pole shoes (14) extending through the rotor support (11).

7. An electric machine according to claim 4, characterized in that the number of stators (2) is two, the two stators (2) being located on either axial side of the rotor (1).

8. An electric machine according to any of claims 1-7, characterized in that the stator (2) comprises a stator core (21), in that the end of the stator core (21) facing the ferrite magnets (13) is provided with stator slots (211), and in that the stator core (21) is provided with stator windings (22).

Technical Field

The invention relates to a motor, in particular to a motor.

Background

In the rotor structure of the existing permanent magnet disc type motor, the position of a magnet in a magnetic circuit is mostly in a surface-mounted structure. As shown in fig. 1-2, the rotor 1 ' and the stator 2 ' are matched, the rotor 1 ' includes a rotor support 11 ' and permanent magnets 12 ', the stator 2 ' includes a stator core 21 ', the end surface of the stator core 21 ' facing the permanent magnets 12 ' is provided with stator slots 211 ', the permanent magnets 12 ' are directly exposed in the air gap, and this structure can bring advantages such as high torque coefficient and back electromotive force coefficient, but has many defects: such as large cogging, large torque ripple, poor low speed stability, etc.

As shown in fig. 2, due to the arrangement of the stator slots 211 ', the air gap field at the position of the permanent magnet 12' is not uniform, which is specifically represented by: the weaker the magnetic field is closer to the notch of the stator slot 211 'and the higher the unevenness of the magnetic field is closer to the surface of the stator core 21', the center of the air gap is relatively uniform. The material adopted by the permanent magnet has good conductivity, so that eddy current loss of the permanent magnet is seriously increased, and the temperature of the permanent magnet is greatly increased so as to be demagnetized. When the motor needs high rotating speed and high power density operation, particularly in a structure that the rotor is clamped between the two stators by the double stators or the multiple stators, the demagnetization phenomenon is more obvious, and the motor can not normally operate. In addition, because of the reason of the rotor structure, the disc motor cannot realize the IPM (interior permanent magnet) rotor structure of the traditional motor, and is basically an SPM (permanent magnet surface mounted) structure at present, so that the d-axis and q-axis inductances of the motor are almost equal (Ld ═ Lq), and the flux weakening speed expansion control cannot be realized.

Disclosure of Invention

The rotor is used for solving the problem that the rotor of the disc type motor in the prior art is easy to generate eddy current in a magnetic field, so that the rotor is demagnetized; the invention provides a motor, and solves the technical problem of low salient pole ratio. The technical scheme of the invention is as follows:

an electric machine comprising a rotor and a stator cooperating with each other, the rotor comprising: a rotor support; the neodymium iron boron permanent magnets are circumferentially distributed on the rotor bracket; the ferrite magnet covers the axial side face, close to the stator, of the neodymium iron boron permanent magnet; and the pole shoe is arranged on the rotor bracket and separates two adjacent neodymium iron boron permanent magnets.

The ferrite magnet is arranged on the axial side face of the neodymium iron boron permanent magnet, so that on one hand, the neodymium iron boron permanent magnet is far away from a stator core, and an air gap magnetic field at the position of the neodymium iron boron permanent magnet is relatively uniform, so that the generation of eddy current is reduced; on the other hand, the position close to the stator core of the motor is replaced by ferrite magnets, and the ferrite magnets have good insulation and hardly generate eddy current loss even in a high-frequency rotating magnetic field; in addition, the ferrite magnet has magnetism, and can compensate the loss of air gap magnetic field intensity brought by air gap increase.

The pole shoes are arranged on the rotor support and separate two adjacent neodymium iron boron permanent magnets, so that the q-axis flux linkage reluctance of the motor is greatly reduced, the q-axis inductance is increased, namely Lq is increased, and the salient pole rate is increased. In addition, the increase of the air gap can reduce the d-axis inductance and increase the salient pole rate, thereby improving the dynamic field weakening performance of the motor.

Further, neodymium iron boron permanent magnet circumference distributes on rotor support's same axial side, ferrite magnet covers on the axial side of keeping away from rotor support of neodymium iron boron permanent magnet.

Further, the stator is one, and the stator is located on the axial outer side of the rotor close to the ferrite magnet.

Further, the circumference of rotor support distributes there is the mounting hole, the neodymium iron boron permanent magnet inlays to be established in the mounting hole, the axial both sides of neodymium iron boron permanent magnet all cover have ferrite magnet.

Further, the mounting holes are filled with ferrite magnets on two sides of the neodymium iron boron permanent magnet in a matching mode.

Furthermore, the number of the stators is two, and the two stators are respectively positioned on two axial sides of the rotor.

Further, the pole shoe is made of high magnetic permeability soft magnetic material, and the pole shoe penetrates through the rotor support.

Furthermore, the stator comprises a stator core, a stator slot is formed in one end, facing the ferrite magnet, of the stator core, and a stator winding is arranged on the stator core.

Based on the technical scheme, the invention can realize the following technical effects:

1. according to the motor, the ferrite magnet is arranged on the axial side face of the neodymium iron boron permanent magnet, on one hand, the neodymium iron boron permanent magnet is far away from a stator core, and an air gap magnetic field at the position of the neodymium iron boron permanent magnet is relatively uniform, so that the generation of eddy current is reduced; on the other hand, the position close to the stator core of the motor is replaced by ferrite magnets, and the ferrite magnets have good insulation and hardly generate eddy current loss even in a high-frequency rotating magnetic field; in addition, the ferrite magnet has magnetism, and can compensate the loss of the air gap magnetic field intensity caused by the increase of the air gap;

2. according to the motor, the neodymium iron boron permanent magnet and the ferrite magnet can be arranged on one axial side surface of the rotor support, and the formed rotor can be matched with one stator; a neodymium iron boron permanent magnet can be embedded on the rotor support, the two circumferential sides of the neodymium iron boron permanent magnet are covered with ferrite magnets, and the formed rotor can be axially clamped between the two stators and is matched with the two stators; pole shoes are further arranged to separate two adjacent neodymium iron boron permanent magnets, and the q-axis flux linkage reluctance of the motor can be greatly reduced through the pole shoe structure, so that the q-axis inductance Lq is increased, and the salient pole effect is realized; the inductance Ld of the d axis is reduced by matching with the increase of the air gap, the salient pole ratio p is Lq/Ld, and the salient pole ratio is increased, so that the dynamic field weakening performance of the motor can be improved;

3. according to the motor, the length of the air gap between the stator and the rotor is increased, the generation of eddy current can be reduced, the air gap magnetic field at the position of the neodymium iron boron permanent magnet is uniform, and the power loss is small.

Drawings

Fig. 1 is a schematic structural diagram of a rotor and a single stator of a motor in the prior art;

FIG. 2 is a schematic view of a rotor and a double stator of a prior art motor;

fig. 3 is a schematic structural diagram of a motor according to a first embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a rotor according to the first embodiment;

FIG. 5 is a cross-sectional view A-A of FIG. 4;

FIG. 6 is a schematic view of a magnetic field distribution of a rotor and a stator of an electric machine when mated;

FIG. 7 is a cross-sectional view B-B of FIG. 4;

FIG. 8 is a schematic view of a rotor of an electric machine in cooperation with a stator;

fig. 9 is a schematic structural view of a rotor according to a second embodiment of the present invention;

FIG. 10 is a cross-sectional view C-C of FIG. 9;

FIG. 11 is a cross-sectional view D-D of FIG. 9;

fig. 12 is a schematic view of a rotor and a stator of a motor according to a second embodiment;

wherein: 1-a rotor; 11-a rotor support; 111-mounting holes; 112-central shaft hole; 12-a neodymium iron boron permanent magnet; 13-a ferrite magnet; 14-pole shoe; 2-a stator; 21-a stator core; 211-stator slots; 22-a stator winding; 3-a machine shell; 4-end cover; 5-a rotating shaft; 6-a fan; 7-cover plate; 1' -a rotor; 11' -a rotor spider; 12' -a permanent magnet; 2' -a stator; 21' -a stator core; 211' -stator slots.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.