Shaft-diameter combined rotor high-power-factor permanent magnet vernier motor

Abstract

The invention relates to the technical field of permanent magnet vernier motors, in particular to a shaft-diameter combined rotor high-power-factor permanent magnet vernier motor which comprises an axial stator, a shaft-diameter combined rotor and a radial outer rotor, the axial stator and the shaft-diameter combined rotor are coaxially arranged, and the radial outer rotor and the shaft-diameter combined rotor are concentrically arranged. And the radial outer rotor is positioned on the outer side of the shaft-diameter combined rotor. The axial stator comprises an armature iron core, a permanent magnet A and a stator winding, the armature iron core comprises an armature yoke and a plurality of armature teeth arranged on the armature yoke in a protruding mode, and the armature teeth are evenly arranged on the armature yoke along the circumference. The axial and radial combined rotor structure is adopted, so that the axial magnetic field is connected with the radial magnetic field, the armature winding is arranged on the axial disc type stator yoke, and the problem of difficult heat dissipation of the winding is solved; the stator magnetic field is modulated by using the magnetic conductance change caused by the salient poles of the rotor, so that low-speed and large-torque output of the motor can be realized, and the power factor of the permanent magnet vernier motor can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of permanent magnet vernier motors, in particular to a permanent magnet vernier motor with a shaft-diameter combined rotor and a high power factor. Background Art

[0002] Permanent magnet motors have developed rapidly in recent decades due to their advantages of high power density and high torque density, and have become a hot topic of research for scholars at home and abroad. At present, the types of permanent magnet motors that have been studied more include: permanent magnet synchronous motors, flux switching permanent magnet motors, double-pole permanent magnet motors, flux reversal permanent magnet motors, etc. The working principles of the above types of motors are basically based on the air gap fundamental magnetic field to achieve electromechanical energy exchange. In recent years, a new type of permanent magnet vernier motor with high torque density based on the magnetic gear effect has attracted widespread attention from scholars. This type of motor can realize the simultaneous action of the air gap fundamental magnetic field and the air gap harmonic magnetic field on electromechanical energy conversion. Therefore, this type of motor has the advantages of permanent magnet motors, higher torque density, and simpler structure. It is particularly suitable for low-speed and high-torque applications such as ship propulsion and wind power generation. However, the existing permanent magnet vernier motors still have many shortcomings in specific applications, which are specifically reflected in:

[0003] (1) Most of the permanent magnet vernier motors currently available use the rotating magnetic field generated by the armature winding to replace the magnetic field of the low-pole-logarithm permanent magnet array. The stator is placed inside the rotor, making the space inside the stator slot small. When the motor runs for a long time, the temperature rise of the armature winding is high and the heat dissipation conditions are relatively poor.

[0004] (2) The existing permanent magnet vernier motor has a low power factor, which means that for a given output power, the capacity of the drive inverter needs to be increased, which in turn greatly increases the size and mass of the motor, and the cost of the motor also increases accordingly, limiting the application scenarios of the permanent magnet vernier motor. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings existing in the prior art, and to propose a permanent magnet vernier motor with a shaft diameter combined rotor and a high power factor, which is used to solve the problem of difficult heat dissipation of the armature winding on the stator side of the traditional permanent magnet vernier motor, and further improve the torque density and power factor of this type of motor.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A permanent magnet vernier motor with a shaft-diameter combined rotor and a high power factor comprises an axial stator, a shaft-diameter combined rotor and a radial outer rotor. The axial stator and the shaft-diameter combined rotor are coaxially arranged, the radial outer rotor and the shaft-diameter combined rotor are concentrically arranged, and the radial outer rotor is located outside the shaft-diameter combined rotor.

[0008] Preferably, the axial stator comprises an armature core, a permanent magnet A and a stator winding, wherein the armature core comprises an armature yoke and a plurality of armature teeth protruding from the armature yoke, wherein the plurality of armature teeth are evenly arranged along the circumference on the armature yoke; the stator winding adopts a drum-type winding structure; the stator winding is wound on the armature teeth; a permanent magnet A is embedded in each armature tooth, one end face of the permanent magnet A is flush with the surface of the armature tooth, and the other end face of the permanent magnet A is flush with the back face of the armature yoke; the permanent magnet A divides the armature tooth into two parts, and the curvature of the armature tooth satisfies α b1 =α b2 .

[0009] Preferably, the shaft-diameter combined rotor is composed of a plurality of magnetic blocks arranged at intervals along the circumferential direction; each magnetic block is L-shaped, and each magnetic block is composed of an upright L-type magnetic block and a horizontal I-type magnetic block; a split tooth structure is provided at one end of the L-type magnetic block close to the radial outer rotor; adjacent L-shaped magnetic blocks are connected by non-magnetic blocks.

[0010] Preferably, the radial outer rotor comprises a rotor yoke and a plurality of permanent magnets B, the permanent magnets B are attached to the inner surface of the radial outer rotor and are arranged at equal intervals; the permanent magnets B are arc-shaped; the width of the permanent magnets B is l a The radially outer rotor width l b , the width of the vertical L-shaped magnetic block is l m Respectively equal.

[0011] Preferably, the shaft diameter rotor combination satisfies the rotor tooth arc coefficient α m >α n The shaft diameter rotor combination satisfies the rotor tooth magnetic block length h m >h n ; The shaft diameter rotor combination satisfies the rotor slot depth h c <h o ; The shaft diameter rotor combination satisfies the rotor slot arc coefficient α c <1 / 2α m .

[0012] Preferably, the permanent magnet A and the permanent magnet B are both made of neodymium iron boron material, the permanent magnet A is magnetized in a tangential direction, and the magnetization directions of two adjacent permanent magnets A along the circumference are opposite; the permanent magnet B is magnetized in a radial direction, and the magnetization directions of two adjacent permanent magnets B along the circumference are opposite.

[0013] Preferably, the stator winding pole pair number k of the axial stator, the axial diameter combined rotor pole pair number p of the axial diameter combined rotor, and the outer rotor permanent magnet pole pair number of the radial outer rotor should satisfy l: l=k±p.

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

[0015] 1. The present invention satisfies the magnetic field modulation principle and utilizes the change of air gap permeability caused by the rotor salient pole to modulate the stator magnetic field to realize the conversion of electromechanical energy. Compared with the traditional magnetic field modulation motor with only two layers of air gap, it saves motor space and simplifies the design process of the motor.

[0016] 2. The present invention connects the axial magnetic field with the radial magnetic field through the shaft-diameter combined rotor structure, and places the armature winding on the axial disc stator yoke, which is beneficial to the heat dissipation of the armature winding.

[0017] 3. The shaft-diameter combined rotor of the present invention has neither permanent magnets nor windings, and has a simple structure, which is conducive to high-speed operation of the motor. At the same time, the heat dissipation conditions are good, avoiding the possible shedding and irreversible demagnetization of permanent magnets when the traditional rotor permanent magnet motor runs at high speed.

[0018] 4. The present invention adopts a concentrated winding, which has the advantages of shorter ends and smaller leakage reactance, thereby reducing the copper loss of the motor, reducing the cost of the motor and improving the efficiency of the motor.

[0019] 5. The present invention connects the axial magnetic field with the radial magnetic field by combining the rotor with the shaft diameter, and places the armature winding on the disc stator yoke, thereby solving the problem of difficult heat dissipation of the winding. At the same time, compared with the traditional magnetic field modulation motor, one layer of air gap is reduced, which saves the motor space and simplifies the manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the decomposition of the present invention;

[0021] Figure 2 It is a structural diagram of the axial stator in the present invention;

[0022] Figure 3 It is a structural diagram of the shaft-diameter combined rotor of the present invention;

[0023] Figure 4 for Figure 3 A magnified view of the structure of a single L-shaped magnetic block in the middle shaft diameter combined rotor;

[0024] Figure 5 for Figure 4 Side view of a single L-shaped magnetic block;

[0025] Figure 6 is a structural diagram of the radial outer rotor in the present invention;

[0026] Figure 7 Schematic diagram of the magnetization direction of the radial outer rotor permanent magnet in the present invention, in which the direction of the arrow is the magnetization direction;

[0027] Figure 8 It is a schematic diagram of the magnetic flux path of the shaft-diameter combined rotor permanent magnet vernier motor of the present invention. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings, so that those skilled in the art can better understand the advantages and features of the present invention, thereby making a clearer definition of the protection scope of the present invention. The embodiments described in the present invention are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0029] A permanent magnet vernier motor with a shaft diameter combined rotor and high power factor, such as Figure 1 As shown, it includes an axial stator 1, an axial-diameter combined rotor 2 and a radial outer rotor 3. The axial stator 1 is coaxially arranged with the axial-diameter combined rotor 2, the radial outer rotor 3 is concentrically arranged with the axial-diameter combined rotor 2, and the radial outer rotor 3 is located outside the axial-diameter combined rotor 2.

[0030] Specifically, the axial stator 1 includes an armature yoke 1-1, permanent magnets A1-2, armature teeth 1-3 and stator windings 1-4. Figure 2 As shown, the armature teeth 1-3 are in total a plurality of pieces, which are convexly arranged on the armature yoke 1-1 and are evenly arranged along the circumference; the permanent magnets A1-2 are in total a plurality of pieces, which are embedded in the middle of the armature teeth 1-3, dividing the armature teeth 1-3 into two left and right parts, which are mirror-symmetrical about the permanent magnets A1-2, and the armature teeth arcs satisfy α b1 =α b2 , wherein one end face of the permanent magnet A1-2 is flush with the surface of the armature tooth 1-3, and the other end face of the permanent magnet A1-2 is flush with the back face of the armature yoke 1-1; the stator winding 1-4 is a centralized winding, adopts a drum-type winding structure, and is wound on the armature tooth 1-3.

[0031] Specifically, the shaft-diameter combined rotor 2 is composed of a plurality of L-shaped magnetic conductive blocks arranged at intervals along the circumferential direction, such as Figure 3 The L-shaped magnetic conductive block is composed of two parts, namely an L-shaped magnetic conductive block 2-1 and a horizontal straight-shaped magnetic conductive block 2-2. Figure 4 It is an enlarged view of a single L-shaped shaft diameter combined rotor magnetic block. A split tooth structure is provided at one end of the L-shaped magnetic block 2-1 close to the radial outer rotor 3, dividing the shaft diameter combined rotor teeth into two parts. Adjacent L-shaped magnetic blocks are connected with non-magnetic materials.

[0032] Specifically, Figure 5 This is a side view of a single L-shaped shaft diameter combined rotor magnetic block. According to the size correspondence, it needs to satisfy the rotor tooth arc coefficient α m >α n , rotor tooth magnetic block length h m >hn , rotor slot depth h c <h o , rotor slot arc coefficient α c <1 / 2α m .

[0033] Specifically, Figure 6 The radial outer rotor diagram of the shaft-diameter combined rotor high power factor permanent magnet vernier motor is shown in FIG. The radial outer rotor 3 includes a rotor yoke 3-1 and surface-mounted permanent magnets B3-2, wherein there are a plurality of permanent magnets B3-2, which are attached to the inner surface of the radial outer rotor 3 and arranged at equal intervals; the permanent magnets B3-2 are arc-shaped, and the width of the permanent magnets B3-2 is l a The width l of the radially outer rotor 3 b , vertical l-shaped magnetic block 2-1 width l m Respectively equal.

[0034] Specifically, Figure 7 The side view of the axial stator 1 of the shaft-diameter combined rotor high power factor permanent magnet vernier motor, the armature tooth arc satisfies α b1 =α b2 The permanent magnet A1-2 and the permanent magnet B3-2 are both made of neodymium iron boron material, wherein the magnetization direction of the permanent magnet A1-2 is tangential magnetization, and the magnetization directions of two adjacent permanent magnets A1-2 are opposite, and the magnetization direction of the permanent magnet B3-2 is radial magnetization, and the magnetization directions of two adjacent permanent magnets B3-2 are opposite.

[0035] Specifically, the permanent magnet A1-2 and the permanent magnet B3-2 generate a permanent magnetic flux loop as follows: Figure 8 As shown, taking the reverse magnetization of permanent magnet A1-2 as an example, its path is as follows: starting from permanent magnet A1-2, passing through armature yoke 1-1 and armature tooth 1-3, passing through the air gap and flowing through the shaft-diameter combined rotor 2, realizing the coupling of axial magnetic flux and radial magnetic flux through L-shaped magnetic conductive blocks, superimposing with the magnetic flux generated by permanent magnet B3-2 and passing through rotor yoke 3-1, permanent magnet B3-2, shaft-diameter combined rotor 2, air gap, armature tooth 1-3, armature yoke 1-1 in sequence back to permanent magnet A1-2. When permanent magnet 1-2 is magnetized in the forward direction, the above magnetic flux path is opposite to it.

[0036] Specifically, the stator winding pole pair number k of the axial stator 1, the axial diameter combined rotor pole pair number p of the axial diameter combined rotor 2, and the outer rotor permanent magnet pole pair number of the radial outer rotor 3 should satisfy l: l=k±p.

[0037] In summary, the present invention adopts the magnetic field modulation principle, utilizes the effect of the stator tooth salient pole on the magnetic field, and generates harmonic magnetic fields that interact with each other to achieve low-speed, high-torque output of the motor, and has the characteristics of simple structure, high torque density, and flexible drive. The shaft-diameter combined rotor of this motor acts as a high-speed rotating rotor and simultaneously adjusts the stator magnetic field. The radial outer rotor acts as a low-speed rotating rotor and can interact with the high-speed rotating stator air gap magnetic field on the L-shaped rotor, thereby achieving low-speed, high-torque output of the motor. At the same time, the shaft-diameter permanent magnet flux coupling helps to improve the effective permanent magnet air gap flux level of the motor and effectively improve the power factor of the motor.

[0038] The description and practice disclosed in the present invention are easy to think and understand for ordinary technicians in the technical field, and several improvements and modifications can be made without departing from the principles of the present invention. Therefore, modifications or improvements made without departing from the spirit of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A permanent magnet vernier motor with a shaft diameter combined rotor and high power factor, characterized in that: The invention comprises an axial stator (1), an axial-diameter combined rotor (2) and a radial outer rotor (3), wherein the axial stator (1) and the axial-diameter combined rotor (2) are coaxially arranged, the radial outer rotor (3) and the axial-diameter combined rotor (2) are concentrically arranged, and the radial outer rotor (3) is located outside the axial-diameter combined rotor (2).

2. The high power factor permanent magnet vernier motor with shaft diameter combined rotor according to claim 1, characterized in that: The axial stator (1) comprises an armature core, a permanent magnet A (1-2) and a stator winding (1-4); the armature core comprises an armature yoke (1-1) and a plurality of armature teeth (1-3) protruding from the armature yoke, the plurality of armature teeth (1-3) being evenly arranged along the circumference of the armature yoke (1-1); the stator winding (1-4) adopts a drum-type winding structure; the stator winding (1-4) is wound on the armature teeth (1-3); a permanent magnet A (1-2) is embedded in each armature tooth (1-3); one end face of the permanent magnet A (1-2) is flush with the surface of the armature tooth (1-3), and the other end face of the permanent magnet A (1-2) is flush with the back face of the armature yoke (1-1); the permanent magnet A (1-2) divides the armature tooth (1-3) into two parts, and the armature tooth arc satisfies α b1 =α b2 .

3. The high power factor permanent magnet vernier motor with shaft diameter combined rotor according to claim 2, characterized in that: The shaft-diameter combined rotor (2) is composed of a plurality of magnetic conductive blocks arranged at intervals along the circumferential direction; each magnetic conductive block is L-shaped, and each magnetic conductive block is composed of an upright L-shaped magnetic conductive block (2-1) and a horizontal I-shaped magnetic conductive block (2-2); a split tooth structure is provided at one end of the L-shaped magnetic conductive block (2-1) close to the radial outer rotor (3); adjacent L-shaped magnetic conductive blocks are connected by non-magnetic conductive blocks.

4. The high power factor permanent magnet vernier motor with shaft diameter combined rotor according to claim 3 is characterized in that: The radial outer rotor (3) comprises a rotor yoke (3-1) and a plurality of permanent magnets B (3-2), wherein the permanent magnets B (3-2) are attached to the inner surface of the radial outer rotor (3) and are arranged at equal intervals; the permanent magnets B (3-2) are arc-shaped; the width of the permanent magnets B (3-2) is l a The width l of the radially outer rotor (3) b , the width l of the vertical l-shaped magnetic conductive block (2-1) m Respectively equal.

5. The high power factor permanent magnet vernier motor with shaft diameter combined rotor according to claim 3, characterized in that: The shaft diameter rotor combination (2) satisfies the rotor tooth arc coefficient α m >α n The shaft diameter rotor combination (2) satisfies the rotor tooth magnetic block length h m >h n ; The shaft diameter rotor combination (2) satisfies the rotor slot depth h c <h o ; The shaft diameter rotor combination (2) satisfies the rotor slot arc coefficient α c <1 / 2α m .

6. The high power factor permanent magnet vernier motor with shaft diameter combined rotor according to claim 4, characterized in that: The permanent magnet A (1-2) and the permanent magnet B (3-2) are both made of neodymium iron boron material. The magnetization direction of the permanent magnet A (1-2) is tangential magnetization, and the magnetization directions of two adjacent permanent magnets A (1-2) along the circumference are opposite; the magnetization direction of the permanent magnet B (3-2) is radial magnetization, and the magnetization directions of two adjacent permanent magnets B (3-2) along the circumference are opposite.

7. The high power factor permanent magnet vernier motor with shaft diameter combined rotor according to claim 1, characterized in that: The number of stator winding pole pairs k of the axial stator (1), the number of axial diameter combined rotor pole pairs p of the axial diameter combined rotor (2), and the number of outer rotor permanent magnet pole pairs of the radial outer rotor (3) should satisfy l: l = k ± p.

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