CN114629257A - Axial flux motor stator assembly, axial flux motor and control method thereof - Google Patents

Abstract

The invention relates to the field of motors, and discloses an axial magnetic flux motor stator assembly, an axial magnetic flux motor and a control method thereof. Wherein, the axial flux motor stator assembly includes: an outer stator and an inner stator; an outer axial hole is formed around the outer stator, and the inner stator is arranged in the outer axial hole and an inner axial hole is formed around it, The central axis of the outer axial hole coincides with the central axis of the inner axial hole. Compared with the prior art, the axial flux motor stator assembly, the axial flux motor and the control method thereof provided by the embodiments of the present invention have the advantage of increasing the output torque of the axial flux motor.

Description

Axial flux motor stator assembly, axial flux motor and control method thereof

technical field

The invention relates to the field of motors, in particular to an axial magnetic flux motor stator assembly, an axial magnetic flux motor and a control method thereof.

Background technique

The axial flux motor has a compact structure and high torque power density, and is suitable for applications that require high torque density, such as radar, electric vehicles, flywheel energy storage systems, and elevators.

However, the inventor of the present invention found that the axial flux motor in the prior art is generally presented in a flat form in structure, with a relatively large outer diameter and insufficient utilization of the inner diameter space; the number of winding turns is relatively large, and in high-speed applications, A larger supply voltage is required to output the required torque. In practical applications, the axial flux motor is used in conjunction with the inverter and control system. In order to provide high output torque at high speed, it is necessary to match a higher bus voltage. The high bus voltage puts forward higher requirements on the power supply or battery voltage or rectifier circuit of the system. Therefore, how to improve the output torque of the axial flux motor has become an urgent problem to be solved.

SUMMARY OF THE INVENTION

The purpose of the embodiments of the present invention is to provide an axial flux motor stator assembly, an axial flux motor and a control method thereof, which can increase the output torque of the axial flux motor.

In order to solve the above technical problems, embodiments of the present invention provide an axial flux motor stator assembly, including: an outer stator and an inner stator; the outer stator surrounds and forms an outer axial hole, and the inner stator is disposed on the outer stator. An inner axial hole is formed in and around the outer axial hole, and the central axis of the outer axial hole coincides with the central axis of the inner axial hole.

Embodiments of the present invention further provide an axial flux motor, including: a first stator assembly, the first stator assembly being the aforementioned axial flux motor stator assembly; a rotor, the rotor being connected to the The first stator assemblies are arranged at intervals, the rotor includes a rotor axial hole, the central axis of the rotor axial hole coincides with the central axis of the outer axial hole in the axial flux motor stator assembly, and the The rotor is disposed on one side of the first stator assembly in the axial direction.

Embodiments of the present invention also provide an axial flux motor control method, which is applied to the aforementioned axial flux motor, including: detecting the real-time rotational speed of the axial flux motor; if the real-time rotational speed is less than the base speed, Input current into both the outer stator and the inner stator; if the real-time rotational speed is greater than the base speed, input current into the outer stator or the inner stator.

Compared with the prior art, in the embodiment of the present invention, the stator assembly of the axial flux motor is set as a double-layer structure including an outer stator and an inner stator, and the inner stator is arranged in the outer axial hole formed around the outer stator. The outer axial hole formed around the outer stator coincides with the central axis of the central axis and the inner axial hole formed around the inner stator. When the control system detects that the motor speed is lower than the base speed, the inner and outer stators work at the same time and output torque in the same direction. , so as to effectively improve the overall output torque of the motor; in addition, when the control system detects that the motor speed is higher than the base speed, the outer stator winding or the inner stator winding can be disconnected to work in the form of a single stator, and the inductance of the single stator is relatively reduced. , it is easier to achieve high-speed operation requirements and improve the use range of axial flux motors.

In addition, the number of coil turns of the outer stator and the inner stator are different. Setting the number of coil turns of the outer stator and the inner stator to be different can optimize the harmonics and noise vibration generated during the operation of the axial flux motor, so that the running process of the axial flux motor is more stable.

In addition, the coils of the outer stator and the coils of the inner stator are connected to each other. By connecting the coils of the outer stator and the coils of the inner stator to each other, the outer stator and the inner stator can be controlled at the same time.

In addition, the coils of the outer stator and the coils of the inner stator are insulated from each other. The coils of the outer stator and the coils of the inner stator are set to be insulated from each other, and different power bus bars can be used to control the outer stator and the inner stator respectively, or use a three-phase power supply to control the outer stator and the inner stator respectively.

In addition, the axial cross-sectional area of the rotor axial hole is equal to the axial cross-sectional area of the inner axial hole in the axial flux motor stator assembly.

In addition, it also includes: a second stator assembly, the second stator assembly is the aforementioned axial flux motor stator assembly, the first stator assembly and the second stator assembly in the extension direction of the central axis The rotors are opposite to each other and are arranged coaxially; the rotor is arranged between the first stator assembly and the second stator assembly.

In addition, the rotor includes a first rotating part and a second rotating part; the first rotating part is disposed opposite to the outer stator in the stator assembly of the axial flux motor in the extending direction of the central axis; The second rotating part is disposed opposite to the inner stator in the stator assembly of the axial magnetic flux motor in the extending direction of the central axis.

In addition, it also includes: a connecting part, the connecting part is connected with both the first rotating part and the second rotating part, and the connecting part is used to make the first rotating part and the second rotating part mutually fixed or separated from each other.

Description of drawings

1 is a schematic structural diagram of an axial flux motor stator assembly provided by a first embodiment of the present invention;

FIG. 2 is an axial view of the stator assembly of the axial flux motor provided by the first embodiment of the present invention;

3 is a schematic structural diagram of an axial flux motor provided by a second embodiment of the present invention;

4 is a schematic structural diagram of an axial flux motor provided by a third embodiment of the present invention;

FIG. 5 is a schematic flowchart of a method for controlling an axial flux motor according to a fourth embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, each embodiment of the present invention will be described in detail below with reference to the accompanying drawings. However, those of ordinary skill in the art can appreciate that, in the various embodiments of the present invention, many technical details are set forth in order for the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can be realized.

The first embodiment of the present invention relates to an axial flux motor stator assembly. The specific structure is shown in FIGS. 1 and 2 , including: an outer stator 10 and an inner stator 20 , wherein the outer stator 10 surrounds and forms an outer axial hole 11. The inner stator 20 is disposed in the outer axial hole 11 formed around the outer stator 10, and the inner axial hole 21 is formed around the inner stator 20. Wherein, the central axis of the outer axial hole 11 coincides with the central axis of the inner axial hole 21, and both are the axis OO' in Fig. 1 .

Compared with the prior art, the axial flux motor stator assembly provided by the first embodiment of the present invention includes an outer stator 10 and an inner stator 20. Since the inner stator 20 is disposed in the outer axial hole 11 formed around the outer stator 10, And the central axis of the outer axial hole 11 coincides with the central axis of the inner axial hole 21. During use, the outer stator 10 and the inner stator 20 can be powered at the same time, and the outer stator 10 and the inner stator 20 output the same direction of rotation at the same time. torque, thereby increasing the output torque of the axial flux motor. In addition, when in use, only one of the outer stator 10 and the inner stator 20 can be powered according to requirements, the single stator inductance is relatively reduced, it is easier to achieve high-speed operation requirements, and the use range of the axial flux motor is improved.

Specifically, in this embodiment, as shown in FIGS. 1 and 2 , the outer stator 10 includes a plurality of outer stator coils 12 , the inner stator 20 includes a plurality of inner stator coils 22 , the outer stator coil 12 and the coils of the inner stator coil 22 The number of turns is different. By setting the number of coil turns of the outer stator 10 and the inner stator 20 to be different, the harmonics and noise vibrations generated during the operation of the axial flux motor can be optimized, so that the operation process of the axial flux motor is more stable.

Further, in this embodiment, the outer stator coil 12 and the inner stator coil 22 are connected to each other. By connecting the outer stator coil 12 and the inner stator coil 22 to each other, a single power bus can simultaneously input current to the outer stator 10 and the inner stator 20 , thereby simultaneously controlling the outer stator 10 and the inner stator 20 .

It can be understood that the aforementioned connection between the outer stator coil 12 and the inner stator coil 22 is only a specific example in this embodiment, and does not constitute a limitation. In other embodiments of the present invention, the The outer stator coil 12 and the inner stator coil 22 are insulated from each other. The coils of the outer stator 10 and the coils of the inner stator 20 are set to be insulated from each other, and different power bus bars can be used to control the outer stator 10 and the inner stator 20 respectively, or use a three-phase power supply to control the outer stator 10 and the inner stator 20 respectively. , to improve the scope of application of axial flux motors.

A second embodiment of the present invention relates to an axial flux motor. The specific structure is shown in FIG. 3 , including: a first stator assembly 100 . The first stator assembly 100 is the axial flux motor stator assembly provided by the foregoing embodiments, which may include the axial magnetic flux motor provided by the foregoing embodiments. Pass through the outer stator 10 , the outer axial hole 11 , the inner stator 20 and the inner axial hole 21 in the motor stator assembly. The rotor 200, the rotor 200 and the first stator assembly 100 are spaced apart from each other, the rotor 200 is disposed on one side of the first stator assembly 100 in the axial direction (direction A in FIG. 3), and the rotor 100 includes a rotor axial hole 101, the central axis of the rotor axial hole 101 coincides with the central axis of the outer axial hole 11 in the first stator assembly 100, that is, the same axis OO'.

Compared with the prior art, the axial magnetic flux motor provided by the second embodiment of the present invention is provided with the axial magnetic flux motor stator assembly provided by the foregoing embodiments. Therefore, the axial magnetic flux provided by this embodiment The motor also has the technical effects provided by the foregoing embodiments, which will not be repeated here. For details, reference may be made to the specific descriptions of the foregoing embodiments.

Preferably, in this embodiment, the cross-sectional area of the rotor axial hole 101 in the axial direction (direction A in FIG. 3 ) is the same as the cross-sectional area of the inner axial hole 21 in the first stator assembly 100 in the axial direction. equal area. It can be understood that the cross-sectional area of the rotor axial hole 101 in the axial direction (direction A in FIG. 3 ) is equal to the cross-sectional area of the inner axial hole 21 in the first stator assembly 100 in the axial direction only. This embodiment is a specific example, which is not intended to be limiting. In other embodiments of the present invention, the cross-sectional area of the rotor axial hole 101 in the axial direction (direction A in FIG. 3 ) may also be used. Smaller or slightly larger than the cross-sectional area of the inner axial hole 21 in the first stator assembly 100 in the axial direction, for example, the cross-sectional area of the rotor axial hole 101 in the axial direction (direction A in FIG. 3 ) is the same as The difference between the cross-sectional areas of the inner axial holes 21 in the first stator assembly 100 in the axial direction is less than 5%, 10%, etc., of the cross-sectional areas of the rotor axial holes 101 in the axial direction, which can be determined according to actual needs. Make flexible settings.

Preferably, in this embodiment, the rotor 200 includes a first rotating part 202 and a second rotating part 203, wherein the first rotating part 202 is connected to the outer stator 10 in the first stator assembly in the extending direction of the central axis OO' The second rotating part 203 is arranged directly opposite to the inner stator 20 in the first stator assembly 100 in the extending direction of the central axis OO'. The first rotating part 202 is arranged opposite to the stator 10, and the second rotating part 203 is arranged opposite to the inner stator 20. When the outer stator is supplied with power alone, the magnetic field at the position facing the outer stator 10 is more stable and the magnetic field strength is higher. High, the first rotating part 202 can be more stable when it is driven by the outer stator 10, so as to avoid the interference of the rotor rotation in the unstable magnetic field at the part of the rotor facing the inner stator when only the outer stator is powered, improving the Operational stability of axial flux motors. When only supplying power to the inner stator 20, it can be avoided that the part of the rotor facing the outer stator 10 directly interferes with the stability of the axial flux motor.

In addition, the rotor 200 further includes a connecting portion 204 connecting the first rotating portion 202 and the second rotating portion 203 . The connecting part 204 is connected to both the first rotating part 202 and the second rotating part 203 , and the connecting part 204 is used to fix or separate the first rotating part 202 and the second rotating part 203 from each other. Specifically, the connection part 204 separates the first rotating part 202 and the second rotating part 203 from each other when only supplying power to the outer stator 10 or the inner stator 20; 202 and the second rotating part 203 are fixed to each other. It can be understood that the foregoing is only an example of the working principle of the connecting portion 204 in the embodiment of the present invention. In actual use, it may also be that when the outer stator 10 and the inner stator 20 input currents in the same direction, the first The rotating part 202 and the second rotating part 203 are fixed to each other, and the first rotating part 202 and the second rotating part 203 are separated from each other when different-phase currents are input to the outer stator 10 and the inner stator 20 respectively. Specifically, flexible settings can be made according to actual needs.

The third embodiment of the present invention relates to an axial flux motor. The specific structure is shown in FIG. 4 . In addition to the first stator assembly 100 and the rotor 200 , the second stator assembly 300 may also be included. The second stator assembly 300 is the stator assembly of the axial flux motor provided by the foregoing embodiments, and the first stator assembly 100 and the second stator assembly 300 are opposite to each other in the extending direction of the central axis OO' and are arranged coaxially. The rotor 200 is disposed between the first stator assembly 100 and the second stator assembly 300 .

Compared with the prior art, in the axial flux motor provided in the third embodiment of the present invention, the second stator assembly 300 which is additionally disposed opposite to the first stator assembly 100 can effectively strengthen the first stator assembly Magnetic field strength and magnetic field stability between the first stator assembly 100 and the second stator assembly 300, the rotor 200 disposed between the first stator assembly 100 and the second stator assembly 300 can be more stable in a magnetic field with higher strength and higher stability. Stable rotation, thus effectively improving the stability of the axial flux motor.

The fourth embodiment of the present invention provides an axial flux motor control method, which is applied to the axial flux motor provided by the foregoing embodiments. The specific steps are shown in FIG. 5 , including:

Step S101: Detect the real-time rotational speed of the axial flux motor.

Step S102: Determine whether the implemented rotational speed is less than the base speed, if yes, go to step S103; if not, go to step S104.

Step S103: input current into both the outer stator and the inner stator;

Step S104: Input current into the outer stator or the inner stator.

It can be understood that the steps of the above various methods are divided only for the purpose of describing clearly. During implementation, they can be combined into one step or some steps can be split and decomposed into steps, as long as they contain the same logical relationship, they are all in the scope of this patent. Within the scope of protection; adding insignificant modifications to the algorithm or process or introducing insignificant designs, but not changing the core design of the algorithm and process are all within the protection scope of this patent.

It is not difficult to find that this embodiment is an embodiment of an axial flux motor control method corresponding to the foregoing embodiment, and this embodiment can be implemented in cooperation with the foregoing embodiment. The relevant technical details and technical effects mentioned in the foregoing embodiments are still valid in this embodiment, and are not repeated here in order to reduce repetition. Correspondingly, the relevant technical details mentioned in this embodiment can also be applied to other embodiments.

Those skilled in the art can understand that the above-mentioned embodiments are specific examples for realizing the present invention, and in practical applications, various changes in form and details can be made without departing from the spirit and the spirit of the present invention. scope.

Claims (10)

1. An axial flux motor stator assembly, comprising:

an outer stator and an inner stator;

the outer stator surrounds to form an outer axial hole, the inner stator is arranged in the outer axial hole and surrounds to form an inner axial hole, and the central axis of the outer axial hole is overlapped with the central axis of the inner axial hole.

2. The axial flux electric machine stator assembly of claim 1, wherein the outer stator and the inner stator differ in the number of coil turns.

3. The axial-flux electric machine stator assembly of claim 1, wherein the coils of the outer stator and the coils of the inner stator are interconnected.

4. The axial-flux electric machine stator assembly of claim 1, wherein the coils of the outer stator and the coils of the inner stator are insulated from each other.

5. An axial flux motor, comprising:

a first stator assembly being the axial-flux electric machine stator assembly of any of claims 1-4;

the rotor is arranged at an interval with the first stator assembly and comprises a rotor axial hole, the central axis of the rotor axial hole is overlapped with the central axis of an outer axial hole in the stator assembly of the axial flux motor, and the rotor is arranged on one side of the first stator assembly in the axial direction.

6. The axial-flux electric machine of claim 5, wherein the rotor axial bore has a cross-sectional area in the axial direction that is equal to a cross-sectional area of the inner axial bore in the first stator assembly in the axial direction.

7. The axial-flux electric machine of claim 5, further comprising:

a second stator assembly, the second stator assembly being the axial flux electric machine stator assembly of any of claims 1-4, the first and second stator assemblies being diametrically opposed to each other in a direction of extension of the central shaft and being coaxially disposed;

the rotor is disposed between the first stator assembly and the second stator assembly.

8. The axial-flux electric machine of claim 5, wherein the rotor includes a first rotating portion and a second rotating portion;

the first rotating part is arranged opposite to an outer stator in the axial flux motor stator assembly in the extending direction of the central shaft;

the second rotating part is arranged opposite to the inner stator in the stator assembly of the axial flux motor in the extending direction of the central shaft.

9. The axial-flux electric machine of claim 8, further comprising:

a connection part connected with both the first rotation part and the second rotation part, the connection part being used to make the first rotation part and the second rotation part fixed to or separated from each other.

10. An axial-flux electric machine control method applied to the axial-flux electric machine according to any one of claims 5 to 9, comprising:

detecting the real-time rotating speed of the axial flux motor;

if the real-time rotating speed is less than the base speed, current is input into the outer stator and the inner stator;

and if the real-time rotating speed is greater than the base speed, inputting current into the outer stator or the inner stator.

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