A permanent magnet unit, a permanent magnet and a dual-rotor axial permanent magnet motor thereof

Abstract

The invention discloses a permanent magnet unit, a permanent magnet and a dual-rotor axial permanent magnet motor, which belongs to the technical field of permanent magnet motors. The permanent magnet unit includes a main part and two auxiliary parts, the main part is in a fan ring shape, the auxiliary part is attached to the two straight edge ends of the main part, the main part and the auxiliary part are magnetized from S pole to N pole, the magnetization direction of the main part is perpendicular to the fan ring surface, and there is an acute angle between the magnetization direction of the auxiliary part and the magnetization direction of the main part. The permanent magnet is in a ring shape composed of a plurality of permanent magnet units, and the fan ring surface of the main part is perpendicular to the axis of the permanent magnet. The dual-rotor axial permanent magnet motor includes a stator and a rotor, the rotor includes a rotor core and a permanent magnet arranged on the rotor core, the stator includes a stator core and a winding arranged on the stator core, the stator is arranged between the two permanent magnets, and there is an air gap between the stator and the permanent magnet. The axial magnetic field can be strengthened, the magnetic flux density can be increased, and thus the power density and torque density of the motor can be increased.

Description

Technical Field

[0001] The present invention relates to the technical field of permanent magnet motors, and in particular to a permanent magnet unit, a permanent magnet and a dual-rotor axial permanent magnet motor thereof. Background Art

[0002] Halbach array permanent magnet is a magnet structure that uses a special arrangement of magnet units. It is an almost ideal structure in engineering, and can enhance the field strength in a unit direction, and produce the strongest magnetic field with the least amount of magnets. The current Halbach array permanent magnet is usually composed of an axially magnetized main part and a tangentially magnetized auxiliary part arranged alternately. When used in axial permanent magnet motors, it is found that the motor leakage magnetic field phenomenon is very serious, resulting in limited improvement of the motor air gap magnetic density and reduction of the rotor core usage, thus limiting the further improvement of the power density and torque density of the axial permanent magnet motor. Summary of the invention

[0003] The purpose of the present invention is to solve the above technical problems and provide a permanent magnet unit, a permanent magnet and a dual-rotor axial permanent magnet motor thereof. After magnetization, the permanent magnet unit will have three magnetization directions, one of which is the magnetization direction of the main part, which is parallel to the axial direction, and the other two are the magnetization directions of the auxiliary part, which are at an acute angle to the axial direction, so that the magnetization direction has a partial magnetization direction parallel to the axial direction. The three magnetization directions are superimposed on each other, which can strengthen the magnetic field in the axial direction. The permanent magnet of the permanent magnet unit can significantly improve the magnetic flux density, thereby improving the power density and torque density of the axial permanent magnet motor using the permanent magnet.

[0004] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention discloses a permanent magnet unit, which is in the shape of a fan ring, and includes a main part and two auxiliary parts. The main part and the auxiliary parts have the same polarity, the main part is in the shape of a fan ring, and the two auxiliary parts are respectively attached to the two straight edge ends of the main part. The main part and the auxiliary parts are both magnetized from the S pole to the N pole, the magnetization direction of the main part is perpendicular to the fan ring surface of the main part, and there is an acute angle between the magnetization direction of the auxiliary part and the magnetization direction of the main part.

[0005] Preferably, the acute angle is 45°~75°.

[0006] Preferably, the acute angle is 60°.

[0007] Preferably, the main body portion adopts a variable polarity arc coefficient.

[0008] Preferably, the central angle of the permanent magnet unit is αThe central angles of the inner diameter and outer diameter of the main body are β 1 and β 2 , the inner diameter pole arc coefficient of the permanent magnet unit is β 1 and α The outer diameter pole arc coefficient of the permanent magnet unit is β 2 and α ratio.

[0009] Also disclosed is a permanent magnet, which is in a ring shape composed of a plurality of the above-mentioned permanent magnet units, the polarities of two adjacent permanent magnets are opposite, and the sector ring surface of the main body is perpendicular to the axis of the permanent magnet.

[0010] Also disclosed is a dual-rotor axial permanent magnet motor, comprising a stator and two rotors, wherein the rotor comprises an annular rotor core and the above-mentioned permanent magnet, the two rotor cores are arranged along the same axial spacing, a permanent magnet is respectively provided on the facing annular surfaces of the two rotor cores, the permanent magnet is coaxially fixedly connected to the rotor core, and permanent magnet units with opposite polarities on the two permanent magnets correspond to each other, the stator comprises a stator core and a winding arranged on the stator core, the stator core is arranged in a circular ring shape between the two permanent magnets, and an air gap is provided between the stator core and the permanent magnet.

[0011] Preferably, it further comprises an end cover, on which an annular groove for mounting the rotor core is provided, and the permanent magnet is coaxially fixed on the rotor core.

[0012] Preferably, the permanent magnet and the rotor core are fixed by surface mounting.

[0013] Preferably, it also includes a fixing ring, which is installed on the end cover, and the fixing ring is coaxially arranged with the annular groove. The fixing ring is provided with a pressing groove facing the end cover, and the inner ring of the annular groove is provided with a slot. The outer arc surface and the inner arc surface of the main body part are respectively provided with an outer plug-in block and an inner plug-in block, the outer plug-in block is pressed onto the end cover by the pressing groove, and the inner plug-in block is used to be inserted into the slot. The fitting surfaces of the main body part and the auxiliary part are inclined surfaces, and there is an acute angle between the inclined surface of the main body part and the fan ring surface facing the stator.

[0014] Compared with the prior art, the present invention has achieved the following technical effects:

[0015] 1. The permanent magnet unit of the present invention has three magnetizing directions for the main part and the two auxiliary parts after magnetization, one of which is the magnetizing direction of the main part, which is perpendicular to its fan ring surface and parallel to the axial direction when applied to the axial permanent magnet motor. The other two magnetizing directions are the magnetizing directions of the auxiliary parts, which are at an acute angle to the axial direction, so that their magnetizing directions have partial magnetizing directions parallel to the axial direction. The three magnetizing directions are superimposed on each other, which can strengthen the magnetic field in the axial direction. The Halbach array permanent magnet of the permanent magnet unit can significantly improve the magnetic flux density, thereby improving the power density and torque density of the axial permanent magnet motor using the Halbach array permanent magnet.

[0016] 2. The permanent magnet of the present invention is a Halbach array permanent magnet, which adopts the above-mentioned permanent magnet unit that can produce three magnetization directions. When applied to an axial permanent magnet motor, the axial magnetic field strength can be significantly enhanced after magnetization, and the magnetic flux density can be increased, thereby improving the power density and torque density of the axial permanent magnet motor using the permanent magnet. Moreover, the permanent magnet is composed of several small permanent magnet units, which can block the eddy current path and reduce the eddy current loss of the permanent magnet.

[0017] 3. The dual-rotor axial permanent magnet motor of the present invention adopts the above-mentioned Halbach array permanent magnet, in which the permanent magnet unit of one permanent magnet strengthens the magnetic field in the axial direction and converges into the air gap, and then moves axially through the stator to the corresponding permanent magnet unit of the other permanent magnet. Since the auxiliary part of the permanent magnet unit has an acute-angle magnetization direction, part of the magnetic field enters the adjacent permanent magnet unit along the tangential direction, and the other part enters the rotor core along the axial direction, and finally goes through the same magnetic circuit and returns to the permanent magnet unit of the initial permanent magnet, thereby completing the magnetic circuit closure. The closed magnetic circuit can significantly increase the magnetic flux density after cyclic superposition, thereby improving the power density and torque density. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of a dual-rotor axial permanent magnet motor;

[0020] Figure 2 It is a schematic diagram of the top view structure of a dual-rotor axial permanent magnet motor;

[0021] Figure 3 It is a front view structural schematic diagram of a dual-rotor axial permanent magnet motor;

[0022] Figure 4 is a cross-sectional view of a dual-rotor axial permanent magnet motor;

[0023] Figure 5 It is a partial cross-sectional view of a dual-rotor axial permanent magnet motor;

[0024] Figure 6 It is a schematic diagram of the front three-dimensional structure of the permanent magnet;

[0025] Figure 7 It is a schematic diagram of the back three-dimensional structure of the permanent magnet;

[0026] Figure 8 is a schematic diagram of the magnetic pole polarity of a permanent magnet;

[0027] Fig. 9 Schematic diagram of the three-dimensional structure of the permanent magnet unit;

[0028] Fig.10 is a schematic diagram of the central angle of the permanent magnet unit;

[0029] Fig.11 Schematic diagram of the inner diameter center angle and outer diameter center angle of the main part;

[0030] Fig.12 It is a schematic diagram of the front view of the outer arc surface of the permanent magnet unit with the N pole facing outward;

[0031] Fig.13 Schematic diagram of magnetization direction of permanent magnet unit with N pole facing outwards;

[0032] Fig.14 It is a schematic diagram of the front view of the outer arc surface of the permanent magnet unit with the S pole facing outward;

[0033] Fig.15 Schematic diagram of magnetization direction of a permanent magnet unit with the S pole facing outwards;

[0034] Fig.16 It is a schematic diagram of the positional relationship between the end cover and the fixing ring;

[0035] Fig.17 is a schematic diagram of the structure of the fixed ring;

[0036] Fig.18 It is a schematic diagram of the structure of the end cover.

[0037] Explanation of the accompanying drawings: 1. stator core; 2. winding; 3. permanent magnet; 4. rotor core; 5. fixing ring; 6. end cover; 7. permanent magnet unit; 8. main part; 9. auxiliary part; 10. inner block; 11. outer block; 12. press groove; 13. slot; 14. annular groove; 15. air gap. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Example 1

[0040] This embodiment provides a permanent magnet unit, such as Figures 1 to 18 As shown, the permanent magnet unit 7 is in the shape of a fan ring. The permanent magnet unit 7 includes a main part 8 and two auxiliary parts 9, and the main part 8 and the auxiliary parts 9 have the same magnetic pole polarity. The main part 8 is also in the shape of a fan ring, and the two auxiliary parts 9 are respectively attached to the two straight ends of the main part 8. The main part 8 and the two auxiliary parts 9 are fixed to each other as an integral structure, and the fixing method can be a bonding method (i.e., an adhesive method). When the structure of this permanent magnet unit 7 is magnetized, the main part 8 and the two auxiliary parts 9 are magnetized from the S pole to the N pole. At this time, the main part 8 and the two auxiliary parts 9 will have three magnetization directions, one of which is the magnetization direction of the main part 8. The magnetization direction is perpendicular to the fan ring surface of the main part 8. If it is applied to an axial permanent magnet motor in the later stage, it is parallel to the axial direction. The other two magnetizing directions are the magnetizing directions of the auxiliary part 9, which have an acute angle with the magnetizing directions of the auxiliary part 9 and the main part 8. When installed in the axial permanent magnet motor later, they have an acute angle with the axial direction, so that their magnetizing directions are parallel to the axial magnetizing direction. The three magnetizing directions are superimposed on each other, which can enhance the magnetic field in the axial direction, thereby enhancing the magnetic flux density. After the permanent magnet unit is applied to the Halbach array permanent magnet, the magnetic flux density can be significantly improved, thereby improving the power density and torque density of the axial permanent magnet motor using the Halbach array permanent magnet.

[0041] When the permanent magnet unit is used in an axial permanent magnet motor, the specific magnetization direction is analyzed as follows:

[0042] (1) Fig.12 and Fig.13As shown, when the N-pole surface of the main part 8 faces the stator of the axial permanent magnet motor: wherein the M direction is the positive axial direction, the magnetization direction of the main part 8 of the permanent magnet unit 7 starts from the bottom CD (i.e., the back side) of the permanent magnet unit 7 along the M direction, i.e., from the S pole to the N pole parallel to the axial direction (M direction), thus strengthening the magnetic field in the axial direction. The magnetization direction of the auxiliary part 9 on the left is the BP direction, which has an acute angle with the M direction, i.e., the magnetization direction of the auxiliary part 9 on the left is from the S pole to the N pole and deviates to the axial direction (M direction), and the BP direction can be decomposed into the BA direction, which is parallel to the M direction and in the same direction, thus strengthening the magnetic field in the axial direction. The magnetization direction of the auxiliary part 9 on the right is the EP direction, which has an acute angle with the M direction, i.e., the magnetization direction of the auxiliary part 9 on the right is from the S pole to the N pole and deviates to the axial direction (M direction), and the EP direction can be decomposed into the EF direction, which is parallel to the M direction and in the same direction, thus strengthening the magnetic field in the axial direction. Because the main part 8 and the two auxiliary parts 9 can all strengthen the magnetic field in the axial direction, the three magnetic fields are superimposed on each other, thereby strengthening the magnetic flux density.

[0043] (2) Fig.14 and Fig.15 As shown, when the S pole surface of the main part 8 faces the stator of the axial permanent magnet motor: wherein the W direction is the axial negative direction, the magnetizing direction of the main part 8 of the permanent magnet unit 7 starts from the bottom edge IJ (i.e., the front side) of the permanent magnet unit 7 along the W direction, i.e., from the S pole to the N pole, parallel to the axial direction (W direction), so the magnetic field in the axial direction will be strengthened. The magnetizing direction of the auxiliary part 9 on the left is the HP direction, which has an acute angle with the W direction. The HP direction can be decomposed into the GH direction, which is parallel to the W direction and in the same direction, so the magnetic field in the axial direction can also be strengthened. The magnetizing direction of the auxiliary part 9 on the right is the axial KP direction, which has an acute angle with the W direction. The KP direction can be decomposed into the LK direction, which is parallel to the W direction and in the same direction, so the magnetic field in the axial direction can also be strengthened. The main part 8 and the two auxiliary parts 9 can both strengthen the magnetic field in the axial direction, and the three magnetic fields are superimposed on each other, thereby strengthening the magnetic flux density.

[0044] In order to improve the axial magnetic field strengthening effect, in this embodiment, Figures 1 to 18 As shown, the acute angle is selected between 45° and 75°.

[0045] Among them, it can play the best effect of strengthening the axial magnetic field. In this embodiment, Figures 1 to 18 As shown, the acute angle is selected to be 60°. That is, the BP direction has an angle of 60° with the M direction, the EP direction has an angle of 60° with the M direction, the HP direction has an angle of 60° with the W direction, and the KP direction has an angle of 60° with the W direction.

[0046] In this embodiment, Figures 1 to 18 As shown, the main body 8 adopts a variable pole arc coefficient, that is, the inner diameter pole arc coefficient of the main body 8 is different from the outer diameter pole arc coefficient, which facilitates the permanent magnet unit 7 to be assembled into an annular Halbach array permanent magnet, while ensuring that the electromagnetic performance of the motor using the annular Halbach array permanent magnet remains unchanged.

[0047] Further, the algorithm of the polar arc coefficient is as follows. In this embodiment, Figures 1 to 18 As shown, the central angle of the permanent magnet unit 7 is α , the center angle of the inner diameter of the main part 8 is β 1 The center angle of the outer diameter of the main body 8 is β 2 The inner diameter polar arc coefficient of the main body part 8 is β 1 and α The outer diameter polar arc coefficient of the main body part 8 is β 2 and α ratio.

[0048] Example 2

[0049] This embodiment provides a permanent magnet, such as Figures 1 to 18 As shown, the permanent magnet 3 is composed of a plurality of permanent magnet units 7 in the embodiment 1, the polarities of two adjacent permanent magnet units 7 are opposite, and the central angles of the two adjacent permanent magnet units 7 are the same, and the sector ring surface of the main body 8 is perpendicular to the axis of the permanent magnet, so that the permanent magnet 3 formed is a ring-shaped Halbach array permanent magnet. The so-called opposite polarities of two adjacent permanent magnet units 7 can be referred to Figure 8 and Fig.10 As shown, on the same annular surface of the permanent magnet 3, if the surface of one permanent magnet unit 7 is an N-pole surface, the surface of the adjacent permanent magnet unit 7 is an S-pole surface, that is, the N poles and S poles are alternately arranged on the same annular surface.

[0050] When applied to an axial permanent magnet motor, after magnetization, the N-pole surface of the permanent magnet unit 7 faces the magnetization direction of the main part 8 of the stator, such as Fig.12 and Fig.13 As shown, the axial positive magnetic field strength can be enhanced, and the S pole of the permanent magnet unit 7 faces the magnetization direction of the main part 8 of the stator, as shown in FIG. Fig.14 and Fig.15 As shown, the axial negative magnetic field strength can be strengthened, so that the permanent magnet 3 as a whole can strengthen the axial magnetic field strength, which can significantly increase the magnetic flux density, thereby improving the power density and torque density of the axial permanent magnet motor using the permanent magnet 3. Moreover, the permanent magnet 3 is composed of a number of small permanent magnet units 7, which can block the eddy current path and reduce the eddy current loss of the permanent magnet 3.

[0051] Example 3

[0052] This embodiment provides a dual-rotor axial permanent magnet motor, such as Figures 1 to 18 As shown, it includes a stator and two rotors. Each rotor includes a rotor core 4 and a permanent magnet 3 in Example 2. The rotor core 4 is in a ring shape, and the two rotor cores 4 are arranged along the same axial spacing. The two permanent magnets 3 are respectively arranged on the facing annular surfaces of the two rotor cores 4. The permanent magnet 3 is coaxially arranged with the rotor core 4, and the permanent magnet 3 is fixedly connected to the corresponding rotor core 4. The permanent magnet units 7 with opposite polarities on the two permanent magnets 3 correspond to each other, that is, the N-pole surface of one permanent magnet 3 faces the S-pole surface of the other permanent magnet 3. The stator includes a stator core 1 and a winding 2 arranged on the stator core 1, and the stator core 1 is arranged in a circular ring between the two permanent magnets 3, and there is an air gap 15 between the stator core 1 and the permanent magnet 3.

[0053] The specific magnetic circuit analysis is as follows: in one of the permanent magnet units 7 (N pole surface facing the stator) of one of the permanent magnets 3, since the auxiliary part 9 has an acute-angle magnetization direction, the magnetic field is decomposed, and the magnetic field of the auxiliary part 9 can strengthen the magnetic field in the axial direction, and after superimposing with the magnetic field of the main part 8, it converges into the air gap 15, and then the magnetic field passes through the stator along the axial direction, and the magnetic field moves to the corresponding permanent magnet unit 7 (S pole surface facing the stator) of another permanent magnet 3 (defined as the second permanent magnet). Since the auxiliary part 9 has an acute-angle magnetization direction, the magnetic field is decomposed, and a part of the magnetic field enters the adjacent permanent magnet unit 7 (N pole surface facing the stator) along the tangential direction, and the other part enters the rotor core 4 along the axial direction, and finally goes through the same magnetic circuit again, returns to the permanent magnet unit 7 (N pole surface facing the stator) of the initial permanent magnet 3 (i.e., the first permanent magnet), thereby completing the magnetic circuit closure. The closed magnetic circuit can significantly increase the magnetic flux density after superposition, thereby increasing the power density and torque density.

[0054] In this embodiment, Figures 1 to 18 As shown, the dual-rotor axial permanent magnet motor further includes an end cover 6 , on which an annular groove 14 for mounting the rotor core 4 is provided, and the permanent magnet 3 is coaxially fixed on the rotor core 4 .

[0055] In this embodiment, Figures 1 to 18 As shown, the permanent magnet 3 and the rotor core 4 are fixed by surface pasting, that is, by bonding (i.e., gluing), and the permanent magnet units 7 of the permanent magnet 3 are fully pasted on the surface of the rotor core 4.

[0056] Pure surface mounting is a common method used in existing Halbach array permanent magnets. This method has poor connection reliability and the risk of detachment. To solve this problem, in this embodiment, Figures 1 to 18As shown, a reinforcement method is provided. That is, the dual-rotor axial permanent magnet motor further adds a fixing ring 5, which is used to be installed on the end cover 6. The fixing ring 5 is coaxially arranged with the annular groove 14, and a pressing groove 12 is provided on the fixing ring 5 facing the end cover 6. A slot 13 is provided on the inner ring of the annular groove 14 of the end cover 6. Then, an inner plug-in block 10 and an outer plug-in block 11 are respectively provided on the inner arc surface and the outer arc surface of the main body 8, the outer plug-in block 11 is used to be pressed on the end cover 6 by the pressing groove 12, and the inner plug-in block 10 is used to be inserted into the slot 13. In this way, on the basis of gluing, the plug-in block structure of the main body 8, the pressing groove 12 of the fixing ring 5 and the slot 13 of the end cover 6 cooperate with each other, which can strengthen the fixation of the permanent magnet 3 and avoid the risk of the permanent magnet 3 being detached, thereby achieving the purpose of improving the reliability of the motor. The fitting surfaces of the main part 8 and the auxiliary part 9 are inclined surfaces, and there is an acute angle between the inclined surface of the main part 8 and the fan ring surface facing the stator. Therefore, the outward fan-shaped surface of the main part 8 is larger than the fan-shaped surface bonded to the rotor core 4. The main part 8 becomes an inclined platform structure that is wide on the outside and narrow on the inside, and the auxiliary part 9 becomes an inclined platform structure that is narrow on the outside and wide on the inside, so that the main part 8 can press the auxiliary part 9 toward the rotor core 4, and the main part 8 has a bonding and plug-in structure to ensure its fixed stability, so that the auxiliary part 9 does not need to worry about the risk of detaching from the rotor core 4.

[0057] During the specific installation, the permanent magnet unit 7 is first fixed to the rotor core 4 by gluing, and then in the process of gluing the permanent magnet unit 7, the inner plug-in block 10 of the main part 8 of the permanent magnet unit 7 is inserted into the slot 13 of the end cover 6. Finally, after all the permanent magnet units 7 are fixed on the rotor core 4, the fixing ring 5 and the end cover 6 are assembled so that the pressing groove 12 of the fixing ring 5 buckles the outer plug-in block 11 of the main part 8 on the end cover 6, thereby enhancing the fixation.

[0058] In this embodiment, Figures 1 to 18 As shown, the fixing ring 5 can be made of a non-magnetic material with high hardness, such as steel or aluminum alloy.

[0059] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A dual-rotor axial permanent magnet motor, characterized in that: The invention comprises a stator and two rotors, wherein the rotor comprises an annular rotor core and a permanent magnet, wherein the permanent magnet is in a ring shape composed of a plurality of permanent magnet units, wherein the permanent magnet unit is in a fan ring shape, wherein the permanent magnet unit comprises a main part and two auxiliary parts, wherein the polarity of the main part and the auxiliary part are the same, the main part is in a fan ring shape, and the two auxiliary parts are respectively attached to the two straight side ends of the main part, wherein the main part and the auxiliary parts are magnetized from the S pole to the N pole, and the magnetization direction of the main part is perpendicular to the fan ring surface of the main part, and there is a sharp difference between the magnetization direction of the auxiliary part and the magnetization direction of the main part. The acute angle is 60°; the polarities of the two adjacent permanent magnet units are opposite, the sector ring surface of the main body is perpendicular to the axis of the permanent magnet, the two rotor cores are arranged along the same axial spacing, and a permanent magnet is respectively provided on the facing ring surfaces of the two rotor cores, the permanent magnet is coaxially fixedly connected to the rotor core, and the permanent magnet units with opposite polarities on the two permanent magnets correspond to each other, the stator includes a stator core and a winding arranged on the stator core, the stator core is arranged in a circular ring shape between the two permanent magnets, and there is an air gap between the stator core and the permanent magnet, and the main body adopts a variable pole arc coefficient; It also includes an end cover, the end cover is provided with an annular groove for mounting the rotor core, and the permanent magnet is coaxially fixed on the rotor core; It also includes a fixing ring, which is installed on the end cover, the fixing ring is coaxially arranged with the annular groove, the fixing ring is provided with a pressing groove facing the end cover, the inner ring of the annular groove is provided with a slot, the outer arc surface and the inner arc surface of the main part are respectively provided with an outer plug-in block and an inner plug-in block, the outer plug-in block is pressed onto the end cover by the pressing groove, and the inner plug-in block is used to be inserted into the slot, the fitting surfaces of the main part and the auxiliary part are inclined surfaces, and there is an acute angle between the inclined surface of the main part and the fan ring surface facing the stator.

2. A dual-rotor axial permanent magnet motor according to claim 1, characterized in that: The central angle of the permanent magnet unit is α, the central angles of the inner diameter and outer diameter of the main body are β1 and β2 respectively, the inner diameter pole arc coefficient of the permanent magnet unit is the ratio of β1 and α, and the outer diameter pole arc coefficient of the permanent magnet unit is the ratio of β2 and α.

3. A dual-rotor axial permanent magnet motor according to claim 1, characterized in that: The permanent magnet and the rotor core are fixed by surface mounting.

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