Implementation method of axial flux permanent magnet synchronous motor

Abstract

The invention discloses an implementation method of an axial flux permanent magnet synchronous motor, which structurally comprises a casing, a shaft is axially mounted in the middle of the casing, a rotor assembly sleeved on the shaft is mounted in the casing, and a first stator core and a second stator core are mounted on two axial sides of the rotor assembly respectively. The first stator iron core and the second stator iron core are of an asymmetric structure, a winding is wound on the first stator iron core, the second stator iron core is a first yoke iron core or a first magnetic steel assembly, and the first stator iron core and the second stator iron core are designed to be of the asymmetric structure, so that the winding is wound on the first stator iron core, and the winding is wound on the second stator iron core. The axial acting force of the stator cores on the two sides on the rotor assembly is balanced, mechanical abrasion of the bearing is reduced, the service life of the bearing is prolonged, and the operation efficiency and the output torque of the motor are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of axial flux motors, in particular to the design and implementation of a compact axial flux motor, and more particularly to a stator core and rotor structure of an axial flux motor, and a winding method. Background Art

[0002] Due to the characteristics of small size, light weight, and high power density of axial flux motors, the application of axial flux motors in industry has received attention in the industry in recent years. With the development of technology and the expansion of the application occasions of axial flux motors, the requirements for motor volume, weight, torque and other performances are further improved. Usually, there are three structures of axial flux motors. The first structure is a rotor in the middle and stators on both sides, such as Chinese patents CN109217597A, CN109104059A, and CN109194082A. The second structure is a stator in the middle and rotors on both sides, such as Chinese patents CN208623519U and CN109660097A. The third structure is a stator on one side and a rotor on the other side, that is, a single stator and a single rotor structure arranged axially, such as Chinese patents CN107408875B and CN109274240A. For an axial flux motor with one end cover as the mounting surface, the first and second structures are symmetrical balanced electromagnetic structures, with small rotor axial force and small mechanical friction resistance, which are conducive to improving the motor output torque. However, since there are windings on both sides, the three-phase winding must be led out from the motor housing, which will occupy the radial space of the motor housing, which is not conducive to fully exerting the role of the outer ring of the iron core to generate a larger torque, and reduces the electromagnetic torque of the motor. The third structure is an asymmetric electromagnetic structure. The three-phase winding can be led out from the inner ring of the end cover on one side, which will not occupy the radial space of the motor housing. The other side is used for motor installation. Although it simplifies the installation and improves the electromagnetic torque density of the motor, because the rotor is subjected to axial force on one side, the rotor is subjected to a relatively large axial force, which will cause a large mechanical friction resistance, reducing the effective output torque and operating efficiency of the motor. Therefore, how to give full play to the advantages of these three structural motors and overcome their shortcomings, so as to realize an efficient and high-torque density motor that is easy to install, is a technical problem that needs to be solved in this field. Summary of the invention

[0003] The present invention provides a method for realizing an axial flux permanent magnet synchronous motor, which can solve the problem that the axial force exerted on the rotor in the existing asymmetric axial flux motor is relatively large.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a method for realizing an axial flux permanent magnet synchronous motor, the structure of which includes a casing, a shaft is axially installed in the middle of the casing, a rotor assembly sleeved on the shaft is installed inside the casing, a first stator core and a second stator core are respectively installed on the axial sides of the rotor assembly, the first stator core and the second stator core are asymmetric structures, wherein a winding is wound around the first stator core, and the second stator core is a first yoke core or a first magnetic steel assembly. By designing the first stator core and the second stator core as an asymmetric structure, the axial force of the stator cores on both sides on the rotor assembly is balanced, which is beneficial to reducing the mechanical wear of the bearing, extending the bearing life, and improving the motor operation efficiency and output torque.

[0005] Preferably, the first stator core includes a second yoke core and a tooth core arranged on the second yoke core, and the winding is wound on the tooth core. By setting the tooth core, the radial space of the casing can be utilized as much as possible to set the winding, thereby improving the electromagnetic torque.

[0006] Preferably, the rotor assembly includes a magnetic steel fixing disk located in the middle and a second magnetic steel assembly installed on the side of the magnetic steel fixing disk facing the first stator core. When the second stator core is the first yoke core, the first magnetic steel assembly is installed on the other side of the magnetic steel fixing disk. When the second stator core is the first magnetic steel assembly, the first yoke core is installed on the other side of the magnetic steel fixing disk. The positions of the first yoke core and the first magnetic steel assembly can be flexibly replaced, making the structural setting of the rotor assembly more flexible.

[0007] Preferably, the winding adopts a flat copper wire winding, which can greatly improve the slot filling rate, and is beneficial to reducing the size of the motor and improving the torque density of the motor.

[0008] Preferably, the winding adopts a winding structure in which the first pitch y1 is 1, the second pitch y2 is 0, and the combined pitch y is 1, which is beneficial to reducing the length of the winding end, reducing the motor manufacturing cost, reducing the winding resistance, and improving the motor operating efficiency.

[0009] Preferably, the lead wires of the winding are led out from the axial end of the casing, which facilitates the wiring of the motor and does not occupy the radial space of the casing to set the wiring terminal.

[0010] Preferably, the housing is provided with a front cover and a rear cover at both axial ends thereof, respectively, to facilitate installation and maintenance of components inside the housing and to facilitate lead-out of the winding lead wires.

[0011] Preferably, the front end cover or the rear end cover is provided with a through hole, and the lead wire of the winding passes through the through hole, so as to facilitate the lead wire of the winding to be led out.

[0012] Preferably, the axial flux permanent magnet synchronous motor is a three-phase permanent magnet synchronous motor having a higher torque density.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] By designing the first stator core and the second stator core as an asymmetric structure, the axial force of the stator cores on both sides on the rotor assembly is balanced, which is beneficial to reduce the mechanical wear of the bearing, extend the bearing life, and improve the motor operation efficiency and output torque; compared with the symmetrical structure of the stator core, the asymmetric structure has only one set of three-phase windings, which can be directly led out from one side of the end cover and installed and fixed on the other side. The structure is simpler, easy to install and connect, and the internal space of the core is fully utilized to give full play to the advantage of the outer ring generating a large torque; the winding uses flat copper wire to greatly increase the slot fill rate. It is beneficial to reduce the size of the motor and improve the torque density of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an overall exploded view of the three-dimensional structure of the present invention;

[0016] Figure 2 It is a side cross-sectional assembly structure diagram of the present invention;

[0017] Figure 3 An exploded view of the internal structure of Embodiment 1 of the present invention;

[0018] Figure 4 An exploded view of the internal structure of Embodiment 2 of the present invention;

[0019] Figure 5 It is a schematic diagram of the winding method of the winding of the present invention.

[0020] Reference numerals:

[0021] 1. Rear end cover, 11. Bearing, 12. First yoke core, 13. First magnetic steel assembly, 15. Second yoke core, 16. Tooth core, 17. Perforation, 2. Casing, 3. First stator core, 4. Winding, 5. Rotor assembly, 6. Second stator core, 7. Front end cover, 8. Shaft, 9. Second magnetic steel assembly, 10. Magnetic fixing plate. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0023] like Figure 1-5As shown, the present invention solves the problem that the axial force on the rotor in the existing asymmetric axial flux motor is relatively large, and provides the following technical solutions: a method for realizing an axial flux permanent magnet synchronous motor, the structure of which includes a casing 2, a shaft 8 is axially installed in the middle of the casing 2, a rotor assembly 5 sleeved on the shaft 8 is installed inside the casing 2, a first stator core 3 and a second stator core 6 are respectively installed on the axial sides of the rotor assembly 5, the first stator core 3 and the second stator core 6 are asymmetric structures, wherein the first stator core 3 is wound with a winding 4, and the second stator core 6 is a first yoke core 12 or a first magnetic steel assembly 13, and by designing the first stator core 3 and the second stator core 6 as an asymmetric structure, the axial force of the stator cores on both sides on the rotor assembly 5 is balanced, which is beneficial to reducing the mechanical wear of the bearing, extending the bearing life, and improving the motor operation efficiency and output torque.

[0024] Specifically, the first stator core 3, the second stator core 6 and the rotor assembly 5 are all closely arranged along the axial direction of the shaft 8, so that the volume of the entire casing 2 is very small, which can greatly save installation space compared to the traditional radial flux motor. At the same time, the first stator core 3 and the winding 4 can generate a relatively large output torque for the rotor assembly 5, which is more suitable for use as a power component in new energy vehicles.

[0025] When it is working, the first stator core 3 and the winding 4 apply a relatively large output torque to the rotor assembly 5 and also generate a relatively large axial thrust on the rotor assembly 5. Therefore, after the rotor assembly 5 is connected to the shaft 8, the shaft 8 is also subjected to a relatively large axial force, which will cause a large mechanical friction resistance, reducing the effective output torque and operating efficiency of the motor. If a bearing 11 is installed between the shaft 8 and the casing 2, the axial force of the shaft 8 acting on the bearing 11 will increase the burden on the bearing 11, reduce the life of the bearing, and increase mechanical loss.

[0026] Therefore, in the present embodiment, the interaction force between the second stator core 6 and the rotor assembly 5 is used to balance the axial force of the first stator core 3 on the rotor assembly 5, which can greatly reduce the unilateral axial force on the shaft 8, reduce the mechanical wear of the bearing, extend the bearing life, and improve the motor operating efficiency and output torque.

[0027] In this embodiment, if Figure 3-4 As shown, the first stator core 3 includes a second yoke core 15 and a tooth core 16 arranged on the second yoke core 15, the winding 4 is wound on the tooth core 16, the outer edge of the second yoke core 15 is as close to the inner wall of the casing 2 as possible, the tooth core 16 is composed of a plurality of teeth arranged around the center of the circle, and the winding 4 is wound on each tooth. By setting the tooth core 16, the radial space of the casing 2 can be utilized as much as possible to set the winding 4, thereby improving the electromagnetic torque.

[0028] As embodiment 1 of the rotor assembly 5:

[0029] like Figure 3 As shown, the rotor assembly 5 includes a magnetic steel fixing disk 10 located in the middle and a second magnetic steel assembly 9 installed on the side of the magnetic steel fixing disk 10 facing the first stator core 3. When the second stator core 6 is the first yoke core 12, the first magnetic steel assembly 13 is installed on the other side of the magnetic steel fixing disk 10. The second magnetic steel assembly 9 and the first magnetic steel assembly 13 here have the same structure, both of which are annular structures composed of fan-shaped magnetic steel around the circumference, and their areas match the magnetic steel fixing disk 10. The second magnetic steel assembly 9 and the first magnetic steel assembly 13 can both interact with the winding 4 to rotate the rotor assembly 5, and the first magnetic steel assembly 13 simultaneously interacts with the first yoke core 12 to generate axial force, so that the rotor assembly 5 can be subjected to axial forces on both sides.

[0030] As embodiment 2 of the rotor assembly 5:

[0031] like Figure 4 As shown, when the second stator core 6 is the first magnetic steel component 13, the first yoke core 12 is installed on the other side of the magnetic steel fixing disk 10, and the positions of the first yoke core 12 and the first magnetic steel component 13 can be flexibly replaced, so that the structural setting of the rotor assembly 5 is more flexible. Compared with Example 1, the positions of the first yoke core 12 and the first magnetic steel component 13 are replaced, which can produce the same technical effect.

[0032] Among them, when the first yoke core 12 is installed on the other side of the magnetic steel fixing disk 10, a magnetic isolation ring is installed between the magnetic steel fixing disk 10 and the first yoke core 12, which can increase the magnetic flux density at the interface between the magnetic steel fixing disk 10, the first yoke core 12 and the magnetic isolation ring.

[0033] like Figure 5 As shown, the winding 4 adopts a flat copper wire winding, which can greatly improve the slot fill rate. It is beneficial to reduce the size of the motor and improve the torque density of the motor. At the same time, the winding 4 adopts a winding structure in which the first pitch y1 is 1, the second pitch y2 is 0, and the combined pitch y is 1. Figure 5 The figure shows the schematic diagram of the A-phase winding. Since the B and C phases are consistent with the A-phase winding, only the A-phase winding type is drawn. This winding structure is beneficial to reducing the length of the winding end, reducing the motor manufacturing cost, reducing the winding resistance, and improving the motor operating efficiency.

[0034] In order to better utilize the axial space of the casing 2, the lead wires of the winding 4 are led out from the axial end of the casing 2, which is convenient for the wiring of the motor, and does not occupy the radial space of the casing 2 to set the wiring terminal. During installation, one axial end of the casing 2 is used for installation and fixation, and the other end can be used as the lead-out end of the lead wires. At the same time, in order to facilitate installation, the axial ends of the casing 2 are respectively provided with a front cover 7 and a rear cover 1, which are convenient for the installation and maintenance of the internal components of the casing 2, and also convenient for the lead-out of the winding 4. A through hole 17 can be provided on the front cover 7 or the rear cover 1, and the lead wires of the winding 4 pass through the through hole 17, which is convenient for the lead-out of the winding 4.

[0035] In this embodiment, the axial flux permanent magnet synchronous motor is a three-phase permanent magnet synchronous motor, which has a higher torque density.

[0036] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0037] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0038] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A method for realizing an axial flux permanent magnet synchronous motor, the structure of which comprises: A casing (2), wherein a shaft (8) is axially mounted in the middle of the casing (2), characterized in that a rotor assembly (5) sleeved on the shaft (8) is mounted inside the casing (2), and a first stator core (3) and a second stator core (6) are respectively mounted on two axial sides of the rotor assembly (5), wherein the first stator core (3) and the second stator core (6) are asymmetric structures, wherein a winding (4) is wound around the first stator core (3), and the second stator core (6) is a first yoke core (12) or a first magnetic steel assembly (13).

2. The method for realizing the axial flux permanent magnet synchronous motor according to claim 1, characterized in that: The first stator core (3) comprises a second yoke core (15) and a tooth core (16) arranged on the second yoke core (15), and the winding (4) is wound around the tooth core (16).

3. The method for realizing the axial flux permanent magnet synchronous motor according to claim 2, characterized in that: The rotor assembly (5) comprises a magnetic steel fixing disk (10) located in the middle and a second magnetic steel assembly (9) installed on the side of the magnetic steel fixing disk (10) facing the first stator core (3); when the second stator core (6) is the first yoke core (12), the first magnetic steel assembly (13) is installed on the other side of the magnetic steel fixing disk (10); when the second stator core (6) is the first magnetic steel assembly (13), the first yoke core (12) is installed on the other side of the magnetic steel fixing disk (10).

4. The method for realizing the axial flux permanent magnet synchronous motor according to claim 1, characterized in that: The winding (4) is a flat copper wire winding.

5. The method for realizing the axial flux permanent magnet synchronous motor according to claim 4, characterized in that: The winding (4) adopts a winding structure in which the first pitch y1 is 1, the second pitch y2 is 0, and the combined pitch y is 1.

6. The method for realizing the axial flux permanent magnet synchronous motor according to claim 1, characterized in that: The lead wire of the winding (4) is led out from the axial end of the casing (2).

7. The method for realizing the axial flux permanent magnet synchronous motor according to claim 6, characterized in that: A front end cover (7) and a rear end cover (1) are respectively provided at two axial ends of the casing (2).

8. The method for realizing the axial flux permanent magnet synchronous motor according to claim 7, characterized in that: The front end cover (7) or the rear end cover (1) is provided with a through hole (17), and the lead wire of the winding (4) passes through the through hole (17).

9. The method for realizing the axial flux permanent magnet synchronous motor according to claim 1, characterized in that: The axial flux permanent magnet synchronous motor is a three-phase permanent magnet synchronous motor.

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