CN116014942A - Axial magnetism-adjusting permanent magnet synchronous motor and driving method thereof - Google Patents

Abstract

The invention discloses an axial magnetic modulation permanent magnet synchronous motor and a driving method thereof, comprising: a stator, a first rotor and a second rotor; the first rotor and the second rotor are coaxially connected and built in the stator; the first rotor is designed There is a first rib structure, the second rotor is provided with a second rib structure, the first rib structure and the second rib structure form a staggered angle in the axial direction; the end of the first rotor is provided with the first rib structure The inner ring magnetic shaft connected with the inner ring structure, the end of the second rotor is provided with the outer ring magnetic shaft connected with the second rib structure and having a different radius from the inner ring magnetic shaft, and the rib structure of each rotor is connected to it The magnetic shafts of the two rotors are of the same polarity, and the polarities of the two rotors are opposite, so that the magnetic flux on each rotor enters the other rotor along the rib structure and the magnetic shaft connected to the rib structure, forming a closed magnetic circuit. ; The extension ends of the inner ring magnetic shaft and the outer ring magnetic shaft are provided with exciting windings to adjust the magnetic flux of the closed magnetic circuit by adjusting the current of the exciting windings.

Description

Axial magnetic modulation permanent magnet synchronous motor and driving method thereof

technical field

The invention relates to the technical field of permanent magnet synchronous motors, in particular to an axially adjustable permanent magnet synchronous motor and a driving method thereof.

Background technique

The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

Permanent magnet motors have significant advantages such as high efficiency, high power density, and high response speed, making permanent magnet motors vigorously developed and widely used.

According to the inventor's understanding, the existing permanent magnet synchronous motor has the following technical shortcomings:

Although permanent magnet motors have a series of advantages, the inherent characteristics of permanent magnet materials also determine the fact that the air gap magnetic field of the motor is difficult to adjust. When permanent magnet motors are used in electrical equipment such as electric vehicles and high-speed cutting systems, their speed will be affected by the adjustment ability of the air gap magnetic field and the bus voltage, and cannot have a wide range of speed regulation and constant power operation; when permanent magnet motors are used When used in new energy power generation systems such as wind energy and wave energy, fluctuations in loads and new energy sources will make it difficult for generators to maintain constant voltage operation; when permanent magnet motors are used in systems that require high reliability, the ability to demagnetize due to faults is also limited. Unable to meet actual needs. In order to realize the adjustment of the air gap magnetic field, traditional permanent magnet motors often adopt the control strategy of applying demagnetization current to the direct axis of the motor. Although this method can make up for the shortcomings of permanent magnet motors within a certain limit, it cannot fundamentally solve the problem. And permanent magnet motor error, excessive direct axis demagnetization control, will cause more serious problems.

Hybrid excitation is an application form that effectively combines the advantages of permanent magnet motors and electric excitation motors, and makes up for the shortcomings as much as possible. Its advantages are as follows:

1. It can effectively improve the uniform operating speed range of the permanent magnet motor electric drive system and broaden the operating range of the constant power of the motor;

2. Improve the operating efficiency of the electric drive system and reduce the operating loss of the system for magnetic adjustment;

3. Improve the anti-disturbance ability of the power generation system and promote the development of the new energy industry;

4. Increase the motor excitation port to help drive system power improvement field;

5. Enhance the system's multi-margin operation capability and provide fault-tolerant fault operation guarantee

Although the hybrid excitation permanent magnet synchronous motor has the above advantages, it needs to add an electric excitation winding to the high-precision and high-integration permanent magnet motor and construct a suitable magnetic field adjustment circuit. It is necessary to make major changes to the structure of the permanent magnet motor and use more excitation windings. This adjustment may reduce the electromagnetic performance of the motor, affect the ability to adjust the magnetic flux, and greatly increase the cost of motor manufacturing and the difficulty of mass production.

Contents of the invention

In order to solve the above problems, the present invention proposes an axially modulated permanent magnet synchronous motor and its driving method. The magnetic flux on each rotor enters the other rotor along the rib structure and the magnetic shaft connected to the rib structure. A closed magnetic circuit is formed, the magnetic flux of the closed magnetic circuit is adjusted by adjusting the current of the excitation winding, and the magnetic flux adjustment is flexibly realized.

In order to achieve the above object, the present invention adopts the following technical solutions:

In a first aspect, the present invention provides an axially modulated permanent magnet synchronous motor, comprising: a stator, a first rotor, and a second rotor;

The first rotor and the second rotor are coaxially connected and built in the stator;

The yoke of the first rotor is provided with a first rib structure, the yoke of the second rotor is provided with a second rib structure, and the first rib structure and the second rib structure are alternately distributed in the axial direction and form a staggered angle;

The end of the first rotor is provided with an inner ring magnetic shaft connected to the first rib structure, and the end of the second rotor is provided with a second rib structure connected with a radius different from the inner ring magnetic shaft The magnetic shaft of the outer ring, the rib structure of each rotor and the magnetic shaft connected to it are of the same polarity, and the polarities of the two rotors are opposite, so that the magnetic flux on each rotor moves along the rib structure and with the rib The magnetic shaft connected to the internal structure enters another section of the rotor to form a closed magnetic circuit;

The extension ends of the inner ring magnetic shaft and the outer ring magnetic shaft are provided with exciting windings, so as to adjust the magnetic flux of the closed magnetic circuit by adjusting the current of the exciting windings.

As an optional implementation manner, the numbers of the first rib structure and the second rib structure are consistent with the number of pole pairs of the motor.

As an optional implementation manner, the stagger angle is 360/2p degrees, where p is the number of pole pairs of the motor.

As an optional implementation, the rib structure of each segment of the rotor is connected to the N pole or S pole of the corresponding segment of the rotor.

As an optional embodiment, the first rotor and the second rotor are provided with rotor slots, and permanent magnets are arranged in the rotor slots, and the magnetic flux generated by the permanent magnets forms the main magnetic circuit of the motor and the magnetic field adjustment of the motor. The magnetic circuit, the main magnetic circuit of the motor and the magnetizing magnetic circuit of the motor are connected in parallel.

As an optional embodiment, the stator is arranged coaxially with the first rotor and the second rotor, and there is an air gap between the stator and the rotor, and the magnetic flux generated by the permanent magnet enters the air gap to form the main magnetic circuit of the motor.

As an optional embodiment, the inner ring magnetic shaft and the outer ring magnetic shaft extend to one side of the rotor end, and the magnetic shaft is closed at the extended rotor end side, so that the rib structure of the two-stage rotor There is a magnetic flux passing between the magnetic shaft and the magnetic shaft, forming a magnetic circuit for adjusting the magnetic field of the motor.

As an optional embodiment, when the inner ring magnetic shaft and the outer ring magnetic shaft extend to one side of the rotor end, an excitation winding is arranged in the air gap between the inner ring magnetic shaft and the outer ring magnetic shaft .

As an optional implementation, when the field winding applies a field-weakening current, the magnetic flux of the closed magnetic circuit is increased, and the main magnetic flux of the motor flowing through the air gap of the stator and rotor is reduced to realize field-weakening operation; When the current is high, the main flux of each pole of the motor is increased to realize the magnetization operation.

In the second aspect, the present invention provides a driving method for an axially modulated permanent magnet synchronous motor, which is applied to the axially modulated permanent magnet synchronous motor described in the first aspect, including:

The main magnetic circuit of the motor and the magnetic circuit of the motor operating in parallel, the main magnetic circuit of the motor is the magnetic flux generated by the permanent magnet entering the air gap between the stator and the rotor to form the main magnetic circuit of the motor, and the magnetic circuit of the motor is the The magnetic flux above enters the closed magnetic circuit formed after entering another section of the rotor along the rib structure and the magnetic shaft connected to the rib structure;

When the motor starts or works normally, the magnetizing current is applied according to the torque demand through the excitation winding, the magnetic flux generated by the permanent magnet in the closed magnetic circuit is reduced, and the magnetic flux of the main magnetic circuit of the motor is increased;

When the motor is in field-weakening operation, by reducing the current of the excitation winding, the magnetic flux of the closed magnetic circuit is increased, and the magnetic flux of the main magnetic circuit of the motor is reduced.

Compared with prior art, the beneficial effect of the present invention is:

The present invention proposes an axially adjustable permanent magnet synchronous motor and its driving method. The rotor is composed of two sections of rotors, and each section of the rotor is provided with a staggered rib structure, and is connected with the magnetically conductive shaft at the end shaft of the rotor. The ribs of the two rotors are staggered by 360/2p degrees, so that the polarity of the ribs and the magnetic shaft of each rotor is opposite to the polarity of the ribs and the magnetic shaft of the other rotor. The magnetic shafts of the two rotors extend beyond the end of the motor and are closed externally. The magnetic flux of one rotor can enter the other rotor along the "rotor rib-magnetic shaft" to form a closed loop. The field winding is placed in the air gap between the closed ends of the inner and outer ring magnetic shafts of the motor. The field winding can apply current to control the amount of magnetic flux passing through the "rotor rib-magnetic shaft", thereby controlling the magnetic flux of each pole of the rotor. , to achieve flux regulation.

The shaft part of the rotor end of the motor of the present invention leads the leakage magnetic circuit out of the end of the motor through the magnetic conduction shafts of different radii, the space occupied by the branches of the mixed magnetic circuit is small, and the design of the magnetic adjustment structure is easy to realize. The rotor is a conventional spoke-type permanent magnet rotor, which only adopts a segmented structure. The manufacturing process of the motor is simple, and it is easy to manufacture in practice. Its structural complexity and manufacturing cost are lower than that of the existing hybrid excitation structure permanent magnet motor. In addition, in terms of mechanical structure, the motor of the present invention arranges the hybrid excitation winding outside the end of the motor, the mechanical structure of the motor is well integrated, and it can be applied to the operation of various complex working conditions under heavy load and high speed.

The air gap between the inner and outer ring magnetic shafts of the rotor end shaft of the motor of the present invention can be provided with an excitation winding capable of applying current. By controlling the magnitude and direction of the current applied to the excitation winding, the magnitude of the main magnetic flux of the motor can be controlled. Through a reasonable The design can make the excitation winding no current when the motor is running under rated conditions, significantly reducing the excitation loss at the rated operating point of the motor, and helping to improve the operating efficiency of the motor. In addition, the closed part of the inner and outer ring magnetic shafts of the motor end shaft and its excitation winding can be designed as mechanical movable components. Cut off the closed magnetic circuit, further increase the main magnetic flux of the motor, and improve the power energy density and power output of the motor.

Advantages of additional aspects of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations to the present invention.

FIG. 1 is a schematic structural view of a stator provided in Embodiment 1 of the present invention;

Fig. 2 is a schematic diagram of the structure of the rotor magnetization end face provided by Embodiment 1 of the present invention;

Fig. 3 is a schematic diagram of the structure of the rotor non-magnetic modulation end face provided by Embodiment 1 of the present invention;

Among them, 1. The first rotor, 2. The permanent magnet, 3. The first rib structure, 4. The inner ring magnetic shaft, 5. The second rotor, 6. The outer ring magnetic shaft, 7. The second rib structure , 8, excitation winding, 9, inner and outer ring magnetic shaft connection end face, 10, stator, 11, armature winding, 12, stator teeth, 13, stator slot.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the present invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be noted that the terminology used here is only for describing specific embodiments, and is not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and it should also be understood that the terms "comprising" and "having" and any variations thereof are intended to cover a non-exclusive Comprising, for example, a process, method, system, product, or device comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include steps or units not explicitly listed or for these processes, methods, Other steps or units inherent in a product or equipment.

In the case of no conflict, the embodiments and the features in the embodiments of the present invention can be combined with each other.

Example 1

This embodiment provides an axially modulated permanent magnet synchronous motor, including: a stator 10, a first rotor 1 and a second rotor 5;

The first rotor 1 and the second rotor 5 are coaxially connected and built in the stator 10;

The yoke of the first rotor 1 is provided with a first rib structure 3, the yoke of the second rotor 5 is provided with a second rib structure 7, the first rib structure 3 and the second rib structure 7 Staggered distribution in the axial direction and form a staggered angle;

The end of the first rotor 1 is provided with an inner ring magnetic shaft 4 connected with the first rib structure 3, and the end of the second rotor 5 is provided with a second rib structure 7 and connected with the inner ring The outer ring magnetic shaft 6 with different radii of the magnetic shaft 4, the rib structure of each rotor and the magnetic shaft connected to it have the same polarity, and the polarity between the two rotors is opposite, so that the magnetic flux on each rotor Enter another section of the rotor along the rib structure and the magnetic shaft connected to the rib structure to form a closed magnetic circuit;

The extension ends of the inner ring magnetic shaft 4 and the outer ring magnetic shaft 6 are provided with an exciting winding 8 to adjust the magnetic flux of the closed magnetic circuit by adjusting the current of the exciting winding 8 .

In this embodiment, the first rotor 1 and the second rotor 5 are built in the stator 10 and placed coaxially with the stator 10;

As an optional embodiment, as shown in Figure 1, the stator 10 is formed by laminating silicon steel sheets, the stator 10 includes a stator slot 13, stator teeth 12 and a stator yoke, and the stator slot 13 is placed with Armature winding 11.

As an optional implementation manner, the armature winding 11 may be a single-layer winding or a double-layer winding.

As an optional implementation manner, the armature winding 11 can be classified into distributed winding, concentrated winding or lapped winding.

As an optional implementation manner, the number of poles of the armature winding 11 is consistent with the number of rotor magnetic poles.

As an optional implementation, the stator and the rotor are coaxial, and there is an air gap between the stator and the rotor, and a part of the magnetic flux generated by the rotor passes through the outer diameter of the rotor and enters the air gap to form the main pole magnetic flux of the rotor.

As an optional implementation manner, the number of phases of the motor is m≥3, and the number of pole pairs of the motor is p≥1.

In this embodiment, the first rotor 1 and the second rotor 5 have the same structure and are coaxially connected, and each section of the rotor yoke is provided with p rib structures, where p is the number of pole pairs of the motor; and the two sections of the rotor The stagger angle of the rib structure between them is related to the number of pole pairs, which is 360/2p degrees. The rib structure of each segment of the rotor is respectively connected to the N pole or S pole of the corresponding segment of the rotor, so that the rib structure of the segment of the rotor and its The connected magnetic shafts exhibit the same polarity, and the rib structures of the two rotors and their magnetic shafts have opposite polarities.

As an optional implementation manner, both the first rotor and the second rotor are built-in spoke permanent magnet rotors.

As an optional implementation, both the first rotor 1 and the second rotor 5 have rotor slots, and permanent magnets 2 are placed in the rotor slots, and the permanent magnets 2 are arranged in series and parallel to realize "concentration Magnetic effect", forming radial magnetic poles in the radial direction of the rotor, the magnetic flux generated by the permanent magnets can enter the air gap in the radial direction, and the rotor can generate eddy currents when the motor starts, realizing self-starting.

As an optional embodiment, both the first rotor 1 and the second rotor 5 can be made of laminated silicon steel sheets, or made of soft magnetic composite materials with high magnetic permeability, or made of silicon steel sheets and soft magnetic composite materials. Made of magnetic composite materials.

As an optional implementation manner, both the first rotor 1 and the second rotor 5 are solid rotors, and the solid rotors have high magnetic permeability.

As an optional embodiment, the permanent magnet 2 can be a high-performance permanent magnet material, such as NdFeB, rare earth cobalt, etc., or a low-coercivity permanent magnet material, such as AlNiCo or ferrite, etc. .

In this embodiment, the inner ring magnetic shaft 4 and the outer ring magnetic shaft 6 have different radii, and extend to one side of the end of the rotor, and the magnetic shaft is closed on the side of the extended end, so that the two sections There is magnetic flux passing between the rib structure of the rotor and the magnetic shaft; because the polarities of the two rotors are opposite, the magnetic fluxes of different polarities of the two rotors are directed to the end of the rotor and closed at the end, so that each The magnetic flux generated by the permanent magnets on one section of the rotor enters the other section of the rotor along the "rib structure-magnetic shaft", forming a closed magnetic circuit.

In this embodiment, when the inner ring magnetic shaft and the outer ring magnetic shaft extend to one side of the rotor end, a ring-shaped inner and outer ring magnetic shaft with an air gap space is formed. There is an excitation winding in the air gap between the magnetic shafts. By adjusting the current of the excitation winding, the magnetic flux of the closed magnetic circuit can be adjusted, thereby controlling the magnetic flux flowing on the "rib structure-magnetic shaft", so as to control the magnetic flux of each pole. Realize the purpose of motor mixed excitation.

In this embodiment, the magnetic flux generated by the permanent magnets of the rotor is divided into two parts, one part passes through the outer diameter of the rotor and enters the air gap to form the main pole magnetic flux of the rotor, and the other part passes through the staggered rib structure and the inner and outer ring magnetic shafts A closed magnetic circuit is formed, and the magnetic conduction axes of the inner and outer rings present different polarities. An excitation winding is set between the air gaps. By changing the current magnitude and direction of the excitation winding, the magnetic flux generated by the permanent magnet can be controlled through the rib structure. Size, so as to control the magnetic flux of each pole of the motor, and realize the mixed excitation of the motor.

As an optional implementation manner, the excitation winding is placed in the closed structure of the end magnetic conduction shaft, and is a stationary winding. When the motor is running normally, the excitation winding can not apply current or a magnetizing current can be applied. When the excitation winding is applied with a magnetizing current, the main magnetic flux of the motor increases to realize the magnetization operation. When the field winding applies a weak magnetic current, the motor The main magnetic flux is reduced to achieve field weakening operation.

In this embodiment, the magnetic flux generated by the permanent magnet forms two magnetic circuits on the rotor through the "magnetism effect". The first magnetic circuit includes the stator-rotor air gap and the stator, which is the main magnetic circuit of the motor; The circuit includes the rib of the rotor, the rotor magnetic shaft and the connecting end face of the magnetic shaft, which is the magnetic circuit for adjusting the magnetic field of the motor, and the two magnetic circuit branches are connected in parallel.

As shown in Figure 2-Figure 3, in this embodiment, the number of motor phases is 3, the number of stator teeth is 48, the number of rotor slots is 8, the two-stage rotor has 8 ribs in total, the number of permanent magnet blocks is 16, and the number of rotor poles is 8 For example, the rotor includes two sections of the first rotor 1 and the second rotor 5 with the same structure, and the first rotor 1 and the second rotor 5 are coaxially connected;

The first rotor 1 is provided with a first rib structure 3, and the first rib structure 3 is connected to the inner ring magnetic shaft 4;

The second rotor 5 is provided with a second rib structure 7, and the second rib structure 7 is connected to the outer ring magnetic shaft 6;

The stagger angle between the second rib structure 7 and the first rib structure 3 is 360/2p degrees. Taking an 8-pole motor as an example in this embodiment, the stagger angle is 45 degrees, thus forming a staggered angle at the rotor end shaft. Distributed rib structure.

There are 8 rotor slots on each section of the rotor for placing permanent magnets 2. The magnetization directions of the two adjacent permanent magnets 2 are opposite, and the rotor cores between the two adjacent permanent magnets 2 form a radial direction along the radial direction. To the magnetic pole, the magnetic flux generated by the permanent magnet 2 enters the stator core through the air gap through the radial magnetic pole and interlinks with the armature winding to form the main magnetic flux.

The inner ring magnetic shaft 4 and the outer ring magnetic shaft 6 extend beyond the end face of the motor to form the connecting end face 9 of the inner and outer ring magnetic shafts. The air between the inner ring magnetic shaft 4 and the outer ring magnetic shaft 6 There is an excitation winding 8 at the gap; because the rib structure of the two rotors and the magnetic polarity of the corresponding magnetic shaft are opposite, a part of the magnetic flux of each rotor enters the other through the rib structure, the magnetic shaft and the connecting end surface of the magnetic shaft. A segment of the rotor forms a closed magnetic circuit.

When the motor is running, by applying current to the field winding 8, a current that can reduce the magnetic flux of the "rib structure-magnetic shaft" magnetic circuit branch can be applied. At this time, most of the magnetic flux generated by the permanent magnet enters the The stator 10 constitutes the main magnetic flux of the motor, so that the magnetic flux of each pole of the motor is kept at a high level;

It is also possible to apply a weak field current to the field winding 8, and at this time, more magnetic flux passes through the staggered rib structure, the magnetic conduction shaft and the connection end face 9 of the magnetic conduction shaft to form a closed magnetic circuit, and passes through the stator-rotor air gap The magnetic flux of the motor is reduced, thereby reducing the main flux of the motor, so as to realize the field weakening control and widen the constant power operation area of the motor. It can be seen that the mixed excitation of the motor can be realized through the field winding.

In this embodiment, when the motor is running, the main magnetic flux during the running of the motor is dynamically adjusted by applying a magnetizing current to the excitation winding, so as to realize the control of the magnetic flux. After the excitation winding is energized, it can control the flow rate of the magnetic flux generated by the permanent magnet on the ribs of the rotor, thereby indirectly controlling the main magnetic flux of each pole of the rotor and realizing mixed excitation.

When the permanent magnet synchronous motor is working, when the motor has no load and no current, part of the magnetic flux generated by the permanent magnet passes through the radial magnetic pole and enters the stator core through the air gap to interlink with the armature winding to form the main magnetic flux, and the other part passes through the rib structure , magnetic shaft, etc. form a closed magnetic circuit, and the magnetic flux passing through the "rib structure-magnetic shaft" can be controlled by the magnitude and direction of the current of the excitation winding.

When the motor is running with load, after the current is applied to the stator winding, the main magnetic flux generated by the permanent magnet on the rotor of the motor and the armature winding generate a driving torque. The middle current winding applies current, which can realize two effects of magnetic field increase operation or field weakening speed expansion operation, effectively broaden the operating range of the motor, and realize mixed excitation of the motor;

Among them, when the motor is started and running, the magnetizing current is applied through the excitation winding to "magnetize" each magnetic pole of the motor, and the main magnetic flux of each pole of the motor is increased during the starting process to improve the starting ability of the motor;

When the motor is running at high speed, the current of the excitation winding is reduced, and the flow rate of the permanent magnet flux in the "rib-magnetic shaft" structure of the motor is increased, thereby reducing the main flux of the motor flowing through the air gap of the stator and rotor. Realize the speed expansion of field weakening, and effectively expand the constant power operation range of the motor.

In the actual application of the motor, according to the rated speed, rated torque and specific performance requirements of the motor, various parameters of the motor, such as the length of the air gap, the number of turns of the stator armature winding, and the number of turns of the built-in current winding of the rotor, are realized by rationally designing various parameters of the motor. different performance.

Example 2

This embodiment provides a driving method for the axially modulated permanent magnet synchronous motor described in Embodiment 1. The current applied to the stator armature winding interacts with the main magnetic field of the rotor to generate a driving torque. The field winding realizes the function of mixed excitation by regulating the branch magnetic flux of "rib structure-magnetic shaft"; specifically includes:

During the starting process or normal operation of the motor, the excitation winding between the inner and outer ring magnetic shafts at the end of the rotor can apply magnetizing currents of different amplitudes according to the torque demand, so as to reduce the interlacing of the magnetic flux generated by the permanent magnets on the rotor yoke. The flux of the rib structure makes the main magnetic flux of each pole in the radial direction of the motor reach a higher value;

When the motor needs to perform field-weakening operation, the current of the excitation winding between the inner and outer ring magnetic shafts at the end of the rotor is reduced, so that more magnetic flux generated by the permanent magnet passes through the "rib structure-magnetic shaft" structure, thereby reducing The radial main magnetic flux of the motor plays the role of field weakening and speed expansion;

At the same time, the motor can operate without applying the excitation winding current between the inner and outer ring magnetic shafts at the end of the rotor. At this time, part of the magnetic flux generated by the permanent magnet passes through the "rib structure-magnetic shaft" to form a closed magnetic circuit, and part of it constitutes the main body of the motor. Flux, at this point it operates in the same way as a normal motor.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, those skilled in the art do not need to pay creative work Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (10)

1. An axial magnetism-adjusting permanent magnet synchronous motor, comprising: a stator, a first rotor, and a second rotor;

the first rotor and the second rotor are coaxially connected and are arranged in the stator;

the yoke part of the first rotor is provided with a first rib structure, the yoke part of the second rotor is provided with a second rib structure, and the first rib structure and the second rib structure are distributed in a staggered manner in the axial direction and form a staggered angle;

the end part of the first rotor is provided with an inner ring magnetic conduction shaft connected with a first rib structure, the end part of the second rotor is provided with an outer ring magnetic conduction shaft which is connected with a second rib structure and has different radiuses with the inner ring magnetic conduction shaft, the rib structure of each section of rotor and the magnetic conduction shaft connected with the rib structure are of the same polarity, and the polarities of the two sections of rotors are opposite, so that magnetic flux on each section of rotor enters the other section of rotor along the rib structure and the magnetic conduction shaft connected with the rib structure to form a closed magnetic circuit;

and the extending ends of the inner ring magnetic conduction shaft and the outer ring magnetic conduction shaft are provided with exciting windings so as to adjust the magnetic flux of the closed magnetic circuit by adjusting the current of the exciting windings.

2. An axial flux machine as defined in claim 1, wherein the number of said first and second rib structures is equal to the number of pole pairs of the machine.

3. An axial direction magnetic regulating permanent magnet synchronous motor according to claim 1, wherein the stagger angle is 360/2p degrees, and p is the pole pair number of the motor.

4. An axial flux-switching permanent magnet synchronous motor according to claim 1, wherein the rib structure of each segment of the rotor is connected to the N-pole or S-pole of the corresponding segment of the rotor.

5. The axial magnetism-regulating permanent magnet synchronous motor according to claim 1, wherein the first rotor and the second rotor are respectively provided with a rotor groove, permanent magnets are arranged in the rotor grooves, magnetic fluxes generated by the permanent magnets form a motor main magnetic circuit and a motor magnetism-regulating magnetic circuit, and the motor main magnetic circuit and the motor magnetism-regulating magnetic circuit are connected in parallel.

6. An axial magnetism regulating permanent magnet synchronous motor as claimed in claim 5, wherein the stator, the first rotor and the second rotor are coaxially arranged, an air gap is arranged between the stator and the rotor, and magnetic flux generated by the permanent magnet enters the air gap to form a main magnetic circuit of the motor.

7. An axial flux-regulating permanent magnet synchronous motor according to claim 5, wherein the inner ring magnetic conduction shaft and the outer ring magnetic conduction shaft extend to one side of the end part of the rotor, and the magnetic conduction shaft is closed at one side of the end part of the extended rotor, so that magnetic flux passes between the rib structures of the two sections of rotors and the magnetic conduction shaft to form a motor flux-regulating magnetic circuit.

8. An axial flux-switching permanent magnet synchronous motor according to claim 7, wherein the exciting winding is provided in an air gap between the inner ring flux guiding shaft and the outer ring flux guiding shaft when the inner ring flux guiding shaft and the outer ring flux guiding shaft extend to the rotor end portion side.

9. An axially modulated permanent magnet synchronous motor according to claim 1, wherein,

when the field winding applies weak magnetic current, the magnetic flux of the closed magnetic circuit is increased, the main magnetic flux of the motor flowing through the stator and rotor air gap is reduced, and weak magnetic operation is realized;

when the exciting winding applies magnetism increasing current, the main magnetic flux of each pole of the motor is increased, and magnetism increasing operation is realized.

10. A driving method of an axial magnetism-adjusting permanent magnet synchronous motor, characterized in that the driving method is applied to the axial magnetism-adjusting permanent magnet synchronous motor according to any one of claims 1 to 9, and comprises the following steps:

the motor main magnetic circuit is a closed magnetic circuit formed by the fact that magnetic flux on each section of rotor enters the other section of rotor along a rib structure and a magnetic conduction shaft connected with the rib structure;

when the motor starts or works normally, magnetizing current is applied through the exciting winding according to torque requirements, the magnetic flux of the magnetic flux generated by the permanent magnet in the closed magnetic circuit is reduced, and the magnetic flux of the main magnetic circuit of the motor is increased;

when the motor performs the field weakening operation, the current of the exciting winding is reduced, the magnetic flux of the closed magnetic circuit is increased, and the magnetic flux of the main magnetic circuit of the motor is reduced.

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