阅读说明：本技术 基于永磁体和外转子铁心偏心结构设计的正弦波转子 (Sine wave rotor designed based on permanent magnet and outer rotor iron core eccentric structure ) 是由 陈胜林 苏森 韩坤 王志强 于 2021-06-04 设计创作，主要内容包括：本发明涉及电机技术领域,具体公开了一种的基于永磁体和外转子铁心偏心结构设计的正弦波转子；包括外转子铁心、偏心永磁体、定子、内转子铁心和转子轴,多个偏心永磁体交替放置在内转子铁心,偏心永磁体由圆弧边内廓、偏心圆弧外廓以及两侧边组成,外转子铁心外廓为圆形、内廓由周向的多个向内凸起的偏心圆弧构成,偏心圆弧的个数与偏心永磁体的个数相同,且偏心圆弧的位置与偏心永磁体一一对应,外转子铁心的径向内侧与偏心永磁体之间构成了环形气隙；本发明采用基于永磁体和外转子铁心偏心结构设计的转子,改善了电机或发电机的气隙磁密波形,减小气隙磁场中谐波含量,使气隙磁场接近正弦波,提升了电机或发电机的性能。(The invention relates to the technical field of motors, and particularly discloses a sine wave rotor designed based on an eccentric structure of a permanent magnet and an outer rotor iron core; the rotor comprises an outer rotor iron core, eccentric permanent magnets, a stator, an inner rotor iron core and a rotor shaft, wherein the eccentric permanent magnets are alternately arranged in the inner rotor iron core and consist of an arc edge inner outline, an eccentric arc outline and two side edges; the rotor designed based on the permanent magnet and the outer rotor iron core eccentric structure improves the air gap flux density waveform of the motor or the generator, reduces the harmonic content in an air gap magnetic field, enables the air gap magnetic field to be close to a sine wave, and improves the performance of the motor or the generator.)

1. A sine wave rotor based on permanent magnet and outer rotor iron core eccentric structure design comprises an outer rotor iron core, eccentric permanent magnets, a stator, an inner rotor iron core and a rotor shaft, wherein the radial outer side of the outer rotor iron core is arranged at the outer end of the rotor shaft, the radial inner side of the inner rotor iron core is arranged at the inner end of the rotor shaft, the sine wave rotor is characterized in that a plurality of eccentric permanent magnets are alternately arranged along the radial outer side of the inner rotor iron core, the magnetizing directions of two adjacent eccentric permanent magnets are opposite, each eccentric permanent magnet comprises an arc edge inner profile, an eccentric arc outer profile and two side edges, the circle center of the eccentric arc outer profile is positioned on the connecting line of the middle point of the arc edge inner profile and the circle center of the arc edge inner profile, the outer rotor iron core profile is circular, the inner profile comprises a plurality of circumferential eccentric arcs protruding inwards, the number of the eccentric arcs on the outer rotor iron core is the same as the number of the eccentric permanent magnets, the positions of the eccentric arcs correspond to the eccentric permanent magnets one by one, an annular air gap is formed between the radial inner side of the outer rotor iron core and the eccentric permanent magnets, and the stator is arranged in the annular air gap and fixed on the machine shell;

the center of the eccentric arc on the outer rotor iron core is led out to a reverse extension line of a line connecting the circle centers of the eccentric arc on the outer rotor iron core, and the circle center of the eccentric arc on the outer rotor iron core is positioned at the radial outer side of the outer rotor iron core.

2. The sine wave rotor designed based on the eccentric structures of the permanent magnets and the outer rotor core as claimed in claim 1, wherein the included angle between two side edges of the eccentric permanent magnets is an opening angleAnd satisfies the relation:whereinThe radius of the outline of an eccentric arc on the eccentric permanent magnet is the number of pole pairsAnd satisfies the relation:whereinIs the radius of the outer contour of the inner rotor iron core,is the distance between the midpoints of the inner outlines of the eccentric permanent magnets.

3. The sine wave rotor designed based on the permanent magnets and the eccentric structure of the outer rotor core as claimed in claim 2, wherein the distance from the midpoint of the eccentric arc to the geometric center of the outer rotor core isAnd satisfies the relation:the radius of the eccentric arc on the outer rotor iron core isAnd satisfies the relation:。

4. the sine wave rotor designed based on the permanent magnets and the eccentric structure of the outer rotor iron core as claimed in claim 1, further comprising tile-shaped magnetic isolation blocks with the same number as the eccentric permanent magnets, wherein the magnetic isolation blocks are arranged between two adjacent eccentric permanent magnets, and two end points of the eccentric arc on the outer rotor iron core are located on an extension line of connecting lines between the middle points of tile-shaped edges and the geometric centers of the magnetic isolation blocks on two sides of the corresponding eccentric permanent magnets.

5. The sine wave rotor designed based on the eccentric structures of the permanent magnets and the outer rotor core as claimed in claim 4, wherein the tile-shaped inner diameter of the magnet isolation block isAnd satisfies the relation:the tile-shaped outer diameter isAnd satisfies the relation:whereinIs the radius of the outer contour of the inner rotor iron core,the distance between the middle points of the inner and outer outlines of the eccentric permanent magnets is equal to the tile-shaped opening angle of the magnetic isolation blockAnd satisfies the relation:opening angle of the eccentric permanent magnetSatisfy the relationWhereinIs the number of pole pairs.

6. The sine wave rotor designed based on the eccentric structures of the permanent magnets and the outer rotor core as claimed in claim 5, wherein the radius of the profile of the eccentric arc of the eccentric permanent magnets is set to beAnd satisfies the relation:whereinThe coefficient of the magnetic isolation block satisfies the relation:。

7. the sine wave rotor designed based on the permanent magnets and the eccentric structure of the outer rotor core as claimed in claim 6, wherein the distance from the midpoint of the eccentric arc to the geometric center of the outer rotor core isAnd satisfies the relation:(ii) a The radius of the eccentric arc on the outer rotor iron core isAnd satisfies the relation:。

8. the sine wave rotor designed based on the eccentric structures of the permanent magnets and the outer rotor core as claimed in claim 3 or 7, wherein the distance between the center of the eccentric arc profile on the eccentric permanent magnet and the center of the arc edge inner profile is an eccentric valueAnd satisfies the relation:。

9. the sine wave rotor designed based on the permanent magnets and the eccentric structure of the outer rotor core as claimed in claim 8, wherein the distance between the center of the eccentric arc and the geometric center of the outer rotor core is an eccentricity valueAnd satisfies the relation:the radius of the circular outline of the outer rotor iron core isAnd satisfies the relation:。

10. the sine wave rotor designed based on the permanent magnet and the outer rotor core eccentric structure according to claim 1 or 4, wherein the number of the eccentric arcs on the outer rotor core isAnd satisfies the relation:whereinIs the number of pole pairs.

Technical Field

The invention relates to the technical field of motors or generators, and particularly discloses a sine wave rotor designed based on an eccentric structure of a permanent magnet and an outer rotor iron core.

Background

The traditional permanent magnet synchronous motor is mostly applied to high-rotating-speed occasions and needs higher speed regulation precision, so that the traditional permanent magnet synchronous motor is mostly driven and controlled by sine wave phase current, the sine wave phase current needs to interact with sine wave counter electromotive force so as to reduce electromagnetic torque pulsation, and the traditional magnetic suspension energy storage flywheel permanent magnet motor has higher harmonic content of 3, 5 and 7 times in the waveform of the counter electromotive force, so that the motor generates electromagnetic torque pulsation and the performance and the efficiency of the motor are influenced. The main reason that the waveform harmonic content of the back electromotive force of the magnetic suspension energy storage flywheel permanent magnet motor is large is that the sine type of the waveform of the air gap magnetic field of the motor is poor, and more odd harmonics are mixed, so that the air gap magnetic field of the motor is close to a trapezoid, and the harmonic content of the waveform of the back electromotive force is large.

Similarly, the traditional sine wave energy storage flywheel generator is also driven and controlled by sine wave phase current, the sine wave phase current needs to interact with sine wave reverse electromotive force to reduce electromagnetic torque pulsation, and the traditional hollow cup type permanent magnet energy storage flywheel generator has larger harmonic content of 4, 6 and 7 times in the waveform of the back electromotive force, so that the energy storage flywheel generator generates electromagnetic torque pulsation to influence the performance and efficiency of the energy storage flywheel generator, and the main reason for the larger harmonic content of the waveform of the back electromotive force waveform of the hollow cup type permanent magnet energy storage flywheel generator is that the sine type of the waveform of the air gap magnetic field of the energy storage flywheel generator is poorer, more odd harmonics are mixed in, the air gap magnetic field of the energy storage flywheel generator is close to a trapezoid, and therefore, the harmonic content of the waveform of the back electromotive force is larger. Therefore, the optimization of the structure of the motor and the generator is important to reduce the harmonic content of the air-gap magnetic field waveform and enable the air-gap magnetic field waveform to be close to a sine wave.

Disclosure of Invention

The invention aims at solving the technical problems that the harmonic content of the waveform of the back electromotive force in the traditional permanent magnet synchronous motor and the traditional sine wave energy storage flywheel generator is large, and the performance of the motor or the generator is influenced, and designs a sine wave rotor which can optimize the structure of the motor and the generator, reduce the waveform harmonic content of an air gap magnetic field and improve the performance of the motor or the generator.

The invention is realized by the following technical scheme:

a sine wave rotor based on permanent magnet and outer rotor iron core eccentric structure design comprises an outer rotor iron core, eccentric permanent magnets, a stator, an inner rotor iron core and a rotor shaft, wherein the radial outer side of the outer rotor iron core is arranged at the outer end of the rotor shaft, the radial inner side of the inner rotor iron core is arranged at the inner end of the rotor shaft, a plurality of eccentric permanent magnets are alternately arranged along the radial outer side of the inner rotor iron core, the magnetizing directions of two adjacent eccentric permanent magnets are opposite, each eccentric permanent magnet is composed of an arc edge inner profile, an eccentric arc profile and two side edges, the circle center of the eccentric arc profile is positioned on the connecting line of the middle point of the arc edge inner profile and the circle center of the arc edge inner profile, the outer rotor iron core profile is circular, the inner profile is composed of a plurality of circumferential eccentric arcs protruding inwards, the number of the eccentric arcs on the outer rotor iron core is the same as the number of the eccentric permanent magnets, the positions of the eccentric arcs correspond to the eccentric permanent magnets one by one, an annular air gap is formed between the radial inner side of the outer rotor iron core and the eccentric permanent magnets, and the stator is arranged in the annular air gap and fixed on the machine shell;

the center of the eccentric arc on the outer rotor iron core is led out to a reverse extension line of a line connecting the circle centers of the eccentric arc on the outer rotor iron core, and the circle center of the eccentric arc on the outer rotor iron core is positioned at the radial outer side of the outer rotor iron core.

As a further arrangement of the scheme, the included angle of two side edges of the eccentric permanent magnet is a span angleAnd satisfies the relation:whereinThe radius of the outline of an eccentric arc on the eccentric permanent magnet is the number of pole pairs of the motorAnd satisfies the relation:whereinIs the radius of the outer contour of the inner rotor iron core,is the distance between the midpoints of the inner outlines of the eccentric permanent magnets.

As a further arrangement of the above scheme, the distance from the midpoint of the eccentric arc on the outer rotor iron core to the geometric center isAnd satisfies the relation:the radius of the eccentric arc on the outer rotor iron core isAnd satisfies the relation:。

the magnetic isolation device further comprises tile-shaped magnetic isolation blocks which are equal to the eccentric permanent magnets in number, each magnetic isolation block is arranged between two adjacent eccentric permanent magnets, and two end points of an eccentric arc on the iron core of the outer rotor are positioned on an extension line of a connecting line of the middle point and the geometric center of the magnetic isolation blocks on two sides of the corresponding eccentric permanent magnet.

As a further arrangement of the above scheme, the tile-shaped inner diameter of the magnetic isolation block isAnd satisfies the relation:the tile-shaped outer diameter isAnd satisfies the relation:whereinIs the radius of the outer contour of the inner rotor iron core,the distance between the middle points of the inner and outer outlines of the eccentric permanent magnets is equal to the tile-shaped opening angle of the magnetic isolation blockAnd satisfies the relation:tile-shaped opening angle of the eccentric permanent magnetSatisfy the relationWhereinThe number of pole pairs of the motor is shown.

As a further arrangement of the proposal, the radius of the outline of the eccentric arc of the eccentric permanent magnet isAnd satisfies the relation:whereinThe coefficient of the magnetic isolation block satisfies the relation:。

as a further arrangement of the above scheme, the distance from the midpoint of the eccentric arc on the outer rotor iron core to the geometric center isAnd satisfies the relation:(ii) a The radius of the eccentric arc on the outer rotor iron core isAnd satisfies the relation:

。

as a further configuration of the above scheme, a distance between a center of the eccentric arc outline on the eccentric permanent magnet and a center of the arc edge inner outline is an eccentric valueAnd satisfies the relation:。

as a further arrangement of the above scheme, a distance between a center of the eccentric arc on the outer rotor core and the geometric center is an eccentric valueAnd satisfies the relation:the radius of the circular outline of the outer rotor iron core isAnd satisfies the relation:。

as a further arrangement of the above scheme, the number of the eccentric arcs on the outer rotor iron core isAnd satisfies the relation:whereinThe number of pole pairs of the motor is shown.

Compared with the prior art, the invention has the advantages that:

1) the rotor designed based on the permanent magnet and the outer rotor core eccentric structure is adopted, so that the thickness of a radial air gap of the motor or the generator is uneven, the change of the radial thickness of the air gap is more reasonable, the air gap flux density waveform of the motor or the generator is improved, the harmonic content in an air gap magnetic field is reduced, the air gap magnetic field is close to a sine wave, the counter electromotive force waveform of the motor or the generator is improved, the torque pulsation is reduced, and the performance of the motor or the generator is improved.

2) Compared with the traditional coreless permanent magnet motor or coreless energy storage flywheel generator, the permanent magnet is attached to the inner rotor core, so that the radius is reduced, and permanent magnet materials are saved; and the permanent magnets are separated by the magnetic separation blocks, so that magnetic loops generated on the sides of the permanent magnets are reduced, interpolar magnetic leakage is reduced, and the performance of the motor or the generator is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of example 1 of the present invention;

FIG. 2 is a partial schematic structural view of embodiment 1 of the present invention;

FIG. 3 is a schematic diagram showing the comparison between the air gap field of the magnetic suspension energy storage flywheel permanent magnet synchronous motor and the air gap field of the conventional magnetic suspension energy storage flywheel motor in embodiment 1 of the present invention;

FIG. 4 is a schematic structural view of example 2 of the present invention;

FIG. 5 is a partial structural view of embodiment 2 of the present invention;

FIG. 6 is a diagram showing a partial structure in embodiment 2 of the present invention;

fig. 7 is a schematic diagram of a comparison between the air gap field of the hollow-cup type sine wave energy storage flywheel generator according to embodiment 2 of the present invention and the air gap field of the conventional hollow-cup type energy storage flywheel generator.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. 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 application.

The terms "mounted," "disposed," "provided," "connected," "sleeved," "laid," and the like are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. The specific meanings of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail with reference to the accompanying drawings 1-7, in conjunction with the embodiments.

Example 1

Embodiment 1 discloses a sine wave rotor based on an eccentric structure design of a permanent magnet and an outer rotor core and used in a magnetic suspension energy storage flywheel permanent magnet synchronous motor. Referring to the attached drawings 1 and 2, the magnetic suspension energy storage flywheel comprises an outer rotor iron core 1, an eccentric permanent magnet 2, a magnetic suspension energy storage flywheel stator 3, an inner rotor iron core 4 and a rotor shaft 5, wherein the outer rotor iron core 1 and the inner rotor iron core 4 are fixedly connected to the rotor shaft 5, and the outer rotor iron core 1 and the inner rotor iron core 4 can rotate together with the rotor shaft 5. In the specific setting process, the radial outer side of the outer rotor core 1 is installed at the outer end of the rotor shaft 5, and the radial inner side of the inner rotor core 4 is installed at the inner end of the rotor shaft. A plurality of eccentric permanent magnets 2 are alternately arranged along the radial outer side of an inner rotor iron core 4, and the magnetizing directions of two adjacent eccentric permanent magnets 2 are opposite. The eccentric permanent magnets 2 are composed of an arc edge inner contour, an eccentric arc outer contour and two side edges, dots of the eccentric arc outer contour are located on a connecting line of the center point of the arc edge inner contour and the circle center, and the number of the eccentric permanent magnets 2 is determined according to the number of pole pairs. An annular air gap is formed between the radial inner side of the outer rotor iron core 1 and the eccentric permanent magnet 2, and the magnetic suspension energy storage flywheel stator 3 is arranged in the air gap and fixed on the machine shell. The magnetic flux generated by the eccentric permanent magnet 2 forms a closed loop through the outer rotor core 1 and the inner rotor core 4 and an air gap therebetween.

The inner rotor core 4 in this embodiment is circular in shape and has an outer radiusDetermined by the actual demand of the motor. External rotorThe outer contour of the sub-iron core 1 is circular, the inner contour thereof is formed by a group of eccentric arcs, the number of the eccentric arcs is consistent with that of the eccentric permanent magnets 2, the positions of the eccentric arcs correspond to the eccentric permanent magnets 2 one by one, and the number of the eccentric arcs on the outer rotor iron core 1 isAnd satisfies the relation:whereinThe number of pole pairs of the motor is shown.

In this embodiment, the circular outline of the outer rotor core 1, the circular arc edge inner outline of the eccentric permanent magnet 2, and the inner and outer outlines of the inner rotor core 4 are concentrically arranged, and the concentric point is used as the geometric center of the motor (also the geometric center of the rotor). Two end points of an eccentric arc on the outer rotor iron core 1 are positioned on an extension line of a connecting line of two side edges of the corresponding eccentric permanent magnet 2 and the geometric center of the motor, the circle center of the eccentric arc on the outer rotor iron core 1 is positioned on a reverse extension line of a connecting line of the arc-shaped edge of the corresponding eccentric permanent magnet 2 and the geometric center of the motor, and the circle center of the eccentric arc is positioned on the radial outer side of the outline of the outer rotor iron core 1.

As shown in fig. 2, point O is the geometric center of the motor; h₁The point is the middle point of the outline of an eccentric arc on the eccentric permanent magnet, O₁Point being its center, H₂Is the middle point of the inner contour of the arc edge of the eccentric permanent magnet; A. two points B are two end points of an eccentric arc on the outer rotor iron core, and O₂Point being its center, H₃The point is the middle point thereof; is the center point H of the inner outline of the eccentric permanent magnet₁ H₂The distance between them;the radius of the inner rotor iron core outline;the radius of an eccentric arc on the outer rotor iron core;is the radius of the outline of an eccentric arc on the eccentric permanent magnet,the eccentric value between the center of the eccentric arc outline on the eccentric permanent magnet and the center of the arc edge inner outline is obtained;the distance from the middle point of the eccentric arc on the outer rotor iron core to the geometric center of the motor,is the eccentric value between the center of an eccentric arc on the outer rotor iron core and the geometric center,which is the radius of the outer contour of outer rotor core 1.

The dots of the eccentric arc outline on the eccentric permanent magnet are positioned between the midpoint of the arc plate outline and the circle center, namely O₁On line segment OH₂The above. Two end points A, B of the eccentric arc on the outer rotor iron core are on the extension line of the connecting line of the two sides of the corresponding eccentric permanent magnet and the geometric center O of the motor, namely the two sides of the eccentric permanent magnet corresponding to the eccentric arc on the outer rotor iron core are on the line segments OA and OB. The center of the eccentric arc on the outer rotor iron core is positioned on the reverse extension line of the connecting line of the arc edge of the corresponding eccentric permanent magnet and the geometric center of the motor, namely O₂The point is located on the line segment OH₃And is located at the radial outer side of the outer contour of the outer rotor core, and a connecting line O of the center point and the center of the eccentric arc on the outer rotor core 1₂H₃Passes through the radial outer contour of outer rotor core 1.

The parameters relevant in the design are as follows:

the included angle between the two side edges of the eccentric permanent magnet 2 is an opening angleAnd satisfies the relation:whereinThe number of pole pairs of the motor is; the radius of the outline of the eccentric arc of the eccentric permanent magnet isAnd satisfies the relation:whereinWhich is the radius of the outer contour of the inner rotor core 4,the distance between the middle points of the inner and outer outlines of the eccentric permanent magnet; the distance between the center of the eccentric arc outline on the eccentric permanent magnet and the center of the arc edge is an eccentric valueAnd satisfies the relation:。

the distance from the middle point of the eccentric arc on the outer rotor iron core to the geometric center of the motor isAnd satisfies the relation:(ii) a The radius of the eccentric arc group on the outer rotor iron core is as follows:(ii) a The distance between the center of the eccentric arc group on the outer rotor iron core and the geometric center of the motor is an eccentric valueAnd satisfies the relation:(ii) a The outer contour radius of the outer rotor iron core isAnd satisfies the relation:。

the present embodiment uses an inner rotor core outer diameterIs 48mm, and the thickness of the eccentric permanent magnetIs 4mm, the number of pole pairsFor example, the magnetic suspension energy storage flywheel permanent magnet synchronous motor based on the rotor with the eccentric structure of the permanent magnet and the outer rotor iron core is 4, and the eccentric permanent magnet and the outer rotor iron core are designed:

is composed ofObtaining the included angle between two side edges of the eccentric permanent magnet as a span angleIs composed of (45°)；

Is composed ofDetermining the radius of the profile of the eccentric arc of the eccentric permanent magnetSatisfy the requirement ofIn order to facilitate the processing,preferably 47 mm;

is composed ofCalculating the eccentric value of the distance between the center of the eccentric arc outline on the eccentric permanent magnet and the center of the arc edge inner outline=5mm, formulaThe distance from the middle point of the eccentric arc on the outer rotor iron core to the geometric center of the motor is obtainedSatisfy the requirement ofIn order to facilitate the processing,preferably 60 mm;

is composed ofCalculating the radius of the eccentric arc on the outer rotor coreSatisfy the requirement ofIn order to facilitate the processing,preferably 40 mm;

is composed ofObtaining the distance between the center of the eccentric arc on the outer rotor iron core and the geometric center of the motorIs 100mm, is represented by the formulaDetermining the radius of the circular outer side of the outer rotor coreSatisfy the requirement ofIn order to facilitate the processing,preferably 108 mm.

The traditional magnetic suspension energy storage flywheel motor is used as a comparative example, and the motor parameters are that the outer diameter of an outer rotor is 108mm, the inner diameter is 60mm, and the number of pole pairsThe outer diameter of the inner rotor is 48mm, the outer diameter of the permanent magnet is 52mm, the thickness is 4mm, and the inner diameter is 48 mm.

Compared with the traditional magnetic suspension energy storage flywheel motor, the air gap field of the magnetic suspension energy storage flywheel permanent magnet synchronous motor disclosed by the embodiment is closer to a sine wave. In the evaluation process, a Total Harmonic Distortion (THD) is introduced to evaluate the sine of the air-gap magnetic field waveform, the air-gap magnetic field waveform is subjected to Fourier decomposition transformation to obtain the amplitude of each order of harmonic, and the formula is shownTHD is calculated, the smaller the THD, the better the sinusoid. As shown in FIG. 3, compared with the traditional magnetic suspension energy storage flywheel motor structure, the THD is reduced from 31.8% to 16.4%, the THD is reduced by 48.4%, and the air gap magnetic field waveform is closer to a sine wave.

Example 2

Embodiment 2 discloses a sine wave rotor based on permanent magnet and outer rotor core eccentric structure design for a coreless sine wave energy storage flywheel generator. Referring to fig. 4, 5 and 6, it includes an outer rotor core 1, an eccentric permanent magnet 2, a tile-shaped magnetism isolating block 6, a hollow cup stator 3, an inner rotor core 4 and a rotor shaft 5. The outer rotor core 1 and the inner rotor core 4 are both fixedly connected to the rotor shaft 5, so that the outer rotor core 1 and the inner rotor core 4 can rotate together with the rotor shaft 5. In a specific setting process, the radially outer side of the outer rotor core 1 is mounted on the outer end of the rotor shaft 5, and the radially inner side of the inner rotor core 4 is mounted on the inner end of the rotor shaft 5. A plurality of eccentric permanent magnets 2 are alternately arranged along the radial outer side of an inner rotor iron core 4, and the magnetizing directions of two adjacent eccentric permanent magnets 2 are opposite. The eccentric permanent magnets 2 are composed of an arc edge inner contour, an eccentric arc outer contour and two side edges, dots of the eccentric arc outer contour are located on a connecting line of the center point of the arc edge inner contour and the circle center, and the number of the eccentric permanent magnets 2 is determined according to the number of pole pairs. Meanwhile, the tile-shaped magnetic isolation blocks 6 are arranged between two adjacent eccentric permanent magnets 2, and the number of the magnetic isolation blocks is the same as that of the eccentric permanent magnets 2. A motor air gap is formed between the radial inner side of the outer rotor iron core 1 and the eccentric permanent magnet 2, and the hollow cup stator 3 is arranged in the air gap and fixed on the machine shell. The magnetic flux generated by the eccentric permanent magnet 2 forms a closed loop through the outer rotor core 1 and the inner rotor core 4 and an air gap therebetween.

In this embodiment, the inner rotor core 4 is circular and has a radius of its outer contourDetermined by the actual demand of the energy storage flywheel generator. The outer rotor iron core 1 has a circular outline, the inner outline of the outer rotor iron core is formed by a group of eccentric arcs, the number of the eccentric arcs is consistent with that of the eccentric permanent magnets 2, the positions of the eccentric arcs correspond to the eccentric permanent magnets 2 one by one, and the number of the eccentric arcs on the outer rotor iron core 1 is as follows, and the relation is satisfied:whereinThe number of pole pairs of the motor is shown.

In the embodiment, the circular outline of the outer rotor iron core 1, the circular arc-shaped inner outline of the eccentric permanent magnet 2 and the inner and outer outlines of the inner rotor iron core 4 are concentrically arranged, and the concentric point is used as the geometric center of the energy storage flywheel generator. Two end points of an eccentric arc on the iron core of the outer rotor are positioned on a reverse extension line corresponding to a connecting line of the middle point and the geometric center of the tile-shaped edges of the magnetic isolating blocks 6 at two sides of the eccentric permanent magnet 2. The circle center of the eccentric arc on the outer rotor iron core is positioned on the reverse extension line of the connecting line of the midpoint of the inner contour of the corresponding arc edge of the eccentric permanent magnet 2 and the geometric center and is positioned at the radial outer side of the outer contour of the outer rotor iron core 1.

As shown in fig. 5 and 6, point O is the geometric center of the energy storage flywheel generator; h₁The point is the middle point of the eccentric arc outline of the eccentric permanent magnet, O₁Point being its center, H₂Is the middle point of the inner contour of the arc edge of the eccentric permanent magnet; A. two points B are two end points of an eccentric arc on the outer rotor iron core, and O₂Point being its center, H₃The point is the middle point thereof; C. d, E is the middle point of the tile-shaped edge of the magnetic block between adjacent eccentric permanent magnets;is the center point H of the inner outline of the eccentric permanent magnet₁H₂The distance between them;the radius of the inner rotor iron core outline;the radius of an eccentric arc on the outer rotor iron core;the radius of the outline of an eccentric arc on the eccentric permanent magnet;the eccentric value is the distance between the center of the outer contour of the eccentric arc on the eccentric permanent magnet and the center of the inner contour of the arc edge;the distance from the middle point of the eccentric arc on the outer rotor iron core 1 to the geometric center of the energy storage flywheel generator is represented;the eccentric value of the distance between the center of the eccentric arc on the outer rotor iron core and the geometric center;the outer radius of the outer rotor iron core;the inner diameter of the tile-shaped magnetic isolating block,the outer diameter of the tube is the same as the diameter of the tube,is its opening angle;is the opening angle of the eccentric permanent magnet.

The center of the eccentric arc contour on the eccentric permanent magnet is positioned on the connecting line of the midpoint of the arc edge inner contour and the center of the circle, namely O₁On line segment OH₂The above step (1); two end points A, B of an eccentric arc on the outer rotor iron core are positioned on an extension line of a connecting line of the middle point C, D of the magnetic separation block tile-shaped side at two sides of the corresponding eccentric permanent magnet and the geometric center O, namely A is positioned on the extension line of the line segment OC and B is positioned on the extension line of the line segment OD; the center of the eccentric arc on the outer rotor iron core is positioned on the reverse extension line of the connecting line of the midpoint of the inner outline of the arc edge on the corresponding eccentric permanent magnet 2 and the geometric center, namely O₂The point is located on the line segment OH₂Is positioned on the radial outer side of the outline of the outer rotor iron core, namely the connecting line of the midpoint of the eccentric arc on the outer rotor iron core and the circle centerO₂H₃Passing through the radial outer contour of the outer rotor core.

The parameters relevant in the design are as follows:

the tile-shaped inner diameter of the tile-shaped magnetic isolating block isAnd satisfies the relation:the tile-shaped outer diameter isAnd satisfies the relation:whereinIs the radius of the outer contour of the inner rotor iron core,the distance between the middle points of the inner and outer outlines of the eccentric permanent magnets is the tile-shaped opening angleAnd satisfies the relation:simultaneous eccentric permanent magnet tile-shaped opening angleSatisfy the relationWhereinThe number of pole pairs of the energy storage flywheel generator is.

The radius of the outline of the eccentric arc of the eccentric permanent magnet isAnd satisfies the relation:

whereinThe coefficient of the magnetic isolation block satisfies the relation:。

the distance between the eccentric arc outline of the eccentric permanent magnet and the midpoint of the arc edge inner outline is an eccentric valueAnd satisfies the relation:。

the distance from the middle point of the eccentric arc on the outer rotor iron core to the geometric center of the energy storage flywheel generator isAnd satisfies the relation:. The radius of the eccentric arc on the outer rotor iron core isAnd satisfies the relation:。

the distance between the center of the eccentric arc on the outer rotor iron core and the geometric center of the energy storage flywheel generator is an eccentric valueAnd satisfies the relation:. The radius of the circular outline of the outer rotor iron core isAnd satisfies the relation:。

the present embodiment uses an inner rotor core outer diameterIs 58mm, the thickness of the eccentric permanent magnet5mm, number of pole pairsFor example, the hollow cup type sine wave energy storage flywheel generator based on the rotor with the eccentric structure of the permanent magnet and the outer rotor iron core is 6, and the magnetic isolation block, the eccentric permanent magnet and the eccentric outer rotor iron core are designed:

is composed ofObtaining the tile-shaped inner diameter of the magnetic separation blockIs of the formulaObtaining the tile-shaped outer diameter of the magnetic separation blockIs of the formulaDewar tile type opening angleSatisfy the requirement ofIn order to facilitate the processing and the manufacturing,preferably takes on a value ofIs of the formulaCalculating the tile-shaped opening angle of the eccentric permanent magnet 2Is composed of (28.5°)；

Is composed ofDetermining the radius of the profile of the eccentric arc of the eccentric permanent magnetSatisfy the requirement ofIn order to facilitate the processing,preferably 25 mm;

is composed ofObtaining the distance eccentricity value between the center of the eccentric arc outline on the eccentric permanent magnet 2 and the center of the inner outline of the arc edge=38mm；

Is composed ofCalculating the distance from the middle point of the eccentric arc on the outer rotor iron core to the geometric center of the energy storage flywheel generatorSatisfy the requirement ofIn order to facilitate the processing,preferably 70 mm;

is composed ofCalculating the radius of the eccentric arc on the outer rotor coreSatisfy the requirement ofIn order to facilitate the processing,preferably 26 mm;

is composed ofObtaining the distance between the center of an eccentric arc on an outer rotor iron core and the geometric center of an energy storage flywheel generatorIs 96 mm;

is composed ofDetermining the radius of the circular outer side of an eccentric outer rotor coreSatisfy the requirement ofIn order to facilitate the processing,preferably 108 mm.

The traditional hollow cup type energy storage flywheel generator is taken as a comparative example, and the energy storage flywheel generator has the parameters of 108mm of outer diameter of an outer rotor, 70mm of inner diameter and pole pair numberThe outer diameter of the inner rotor is 58mm, the outer diameter of the permanent magnet is 63mm, the thickness is 5mm, and the inner diameter is 58 mm.

Compared with the traditional hollow cup type energy storage flywheel generator, the air gap magnetic field of the hollow cup type sine wave energy storage flywheel generator is closer to a sine wave. Referring to the attached figure 7, the sine of the air-gap magnetic field waveform is evaluated by introducing a Total Harmonic Distortion (THD), the air-gap magnetic field waveform is subjected to Fourier decomposition transformation to obtain the amplitude of each order of harmonic, and the formula is shownTHD is calculated, the smaller the THD, the better the sinusoid. As shown in FIG. 7, compared with the structure of the traditional hollow cup energy storage flywheel generator, the THD is reduced from 38.2% to 16.5%, and is reduced by 56.8%, so that the air gap magnetic field waveform is closer to a sine wave.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.