A double-stator decoupling hybrid excitation axial flux switching motor

Abstract

The present invention discloses a double-stator decoupling hybrid excitation axial flux switching motor. It includes a first stator, a second stator and a rotor installed coaxially. The first stator includes a plurality of permeable magnetic cores, axial magnetic field permanent magnets and magnetic isolation blocks. The permanent magnets are magnetized in parallel permanent axial directions and the magnetization directions of adjacent permanent magnets are opposite. The second stator is provided with a plurality of T-slots. The T-slots divide the second stator into a plurality of stator teeth with a double-tooth structure. Parallel slots are provided between the double teeth of the stator teeth. The adjacent teeth of adjacent stator teeth are wound with armature coils, and the roots of the stator teeth are wound with excitation windings. The rotor includes a magnetic isolation disk and a rotor core arranged on both sides of the magnetic isolation disk. Each core includes a plurality of rotor teeth and a magnetic permeable bridge connecting the rotor teeth. The electrode in the present invention has a small axial length, a relatively short magnetic circuit, a correspondingly small magnetic resistance, a relatively simple structure, and the excitation magnetic field of the motor will not pass through the permanent magnet, which can avoid the occurrence of irreversible demagnetization of the permanent magnet.

Description

Technical Field

[0001] The invention belongs to the technical field of hybrid excitation motors, in particular to a double-stator decoupling hybrid excitation axial flux switching motor. Background Art

[0002] Ordinary permanent magnet motors have advantages such as high power density and high efficiency, but the air gap is a fixed magnetic field generated by permanent magnets, and the air gap magnetic field is difficult to adjust. The air gap magnetic field of the hybrid excitation motor is jointly established by permanent magnets and DC excitation windings. It not only inherits many advantages of permanent magnet motors such as high power density and high reliability, but also has the advantage of flexible adjustment of the magnetic field of the electric excitation motor. Its air gap magnetic field can be smoothly adjusted, and it has the advantages of small size, light weight and high efficiency. It has broad application prospects in the industrial field.

[0003] The flux switching permanent magnet motor proposed by French scholar E. Hoang in 1997 is a stator permanent magnet motor. The stator and rotor of this motor adopt a double salient pole structure. The permanent magnets and windings are placed on the stator. There are neither permanent magnets nor windings on the rotor. It has a simple structure, is easy to dissipate heat and cool, and has high mechanical strength. The hybrid excitation flux switching motor has the advantages of both the flux switching motor and the hybrid excitation motor. The air gap flux density is adjusted by controlling the magnitude and direction of the excitation current. It has the advantages of reliable operation and high power density of the flux switching permanent magnet motor, high efficiency of the hybrid excitation motor, and smooth adjustment of the air gap magnetic field.

[0004] At present, the common disadvantages of hybrid excitation flux switching motors are that the magnetic adjustment range is not wide enough, the cogging torque and harmonic components are relatively large, which limits their application in wide-speed drive system applications. Summary of the invention

[0005] The purpose of the present invention is to provide a double-stator decoupling hybrid excitation axial flux switching motor to solve the problems existing in the prior art of hybrid excitation axial magnetic field flux switching motor, such as insufficient air gap magnetic field adjustment range, large cogging torque and harmonic components, and permanent magnet demagnetization.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A double-stator decoupling hybrid excitation axial flux switching motor comprises a first stator, a second stator and a rotor which are coaxially mounted, wherein the rotor is located between the first stator and the second stator and has an air gap with the first stator and the second stator;

[0008] The first stator includes 6 permeable cores, 12 axial magnetic field permanent magnets, 6 concentrated armature coils, and 6 magnetic isolation blocks; the permeable cores and magnetic isolation blocks are placed in succession to form a stator disk, and the axial magnetic field permanent magnets are magnetized in parallel with the axial direction of the permanent magnets, and the magnetization directions of adjacent permanent magnets are opposite;

[0009] The second stator core on the second stator is provided with 12 T-shaped slots, the T-shaped slots divide the second stator into 12 No. 2 stator teeth with double-tooth structures, parallel slots are provided between the double teeth of the No. 2 stator teeth, armature coils are wound between adjacent single teeth of adjacent No. 2 stator teeth, and excitation windings are wound around the roots of the No. 2 stator teeth;

[0010] The rotor includes a magnetic separator and a No. 1 rotor core and a No. 2 rotor core arranged on both sides of the magnetic separator. The No. 1 rotor core and the No. 2 rotor core each include 11 rotor teeth and a magnetic bridge connecting the rotor teeth. The asymmetric sector angles of the rotor teeth on the No. 1 rotor core and the No. 2 rotor core are in opposite directions.

[0011] Preferably, the magnetically conductive core includes stator teeth No. 1 and middle teeth on both sides, the bottoms of the middle teeth and the stator teeth No. 1 are connected through a stator yoke, and stator slots are radially arranged between the stator teeth No. 1 and the middle teeth.

[0012] Preferably, the axial magnetic field permanent magnet is arranged on the surface of the axial number one stator tooth, and the axial magnetic field permanent magnet is magnetized along the axial direction, and the magnetization directions of the axial magnetic field permanent magnets on adjacent number one stator teeth are opposite.

[0013] Preferably, the excitation winding is wound on the root of the second stator tooth, and the directions of current flowing into adjacent excitation windings are opposite.

[0014] Preferably, the stator tooth No. 1 of the first stator is a parallel tooth structure; the middle tooth of the first stator is a parallel tooth structure; the axial magnetic field permanent magnet is a parallel permanent magnet structure; the magnetic isolation block is a parallel structure; the stator tooth No. 2 of the second stator has the same double tooth cross-section, and parallel grooves are provided in the double teeth.

[0015] Preferably, the first stator concentrated armature coils are wound on adjacent No. 1 stator teeth of adjacent conductive cores, 6 concentrated armature coils form three phases, and every two concentrated armature coils are connected in series to form a phase winding; the second stator concentrated armature coils are wound between adjacent single teeth of adjacent No. 2 stator teeth, 12 concentrated armature coils form three phases, and every four concentrated armature coils are connected in series to form a phase winding; the concentrated armature coils facing each other on the first stator and the second stator are connected in series.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) the motor has a small axial length, a relatively short magnetic circuit, a correspondingly small magnetic resistance, and a relatively simple structure; (2) the excitation magnetic field of the motor will not pass through the permanent magnet, thereby avoiding the occurrence of irreversible demagnetization of the permanent magnet; (3) the stators on both sides of the motor have armature coils. When the armature coil is short-circuited, the magnetic field generated by the permanent magnet can be offset by adjusting the electric excitation current, thereby having a better fault demagnetization capability; (4) there are no permanent magnets and windings on the rotor, the structure is simple, the operation is reliable, and it can be used for high-speed operation; (5) the rotor teeth on both sides are The asymmetric sector angles are in opposite directions, which can improve the air gap magnetic field distribution and magnetic circuit saturation and reduce the cogging torque; (6) The stator cores on both sides adopt a multi-tooth structure to effectively reduce the cogging torque; (7) The armature coil and the excitation winding both adopt concentrated windings with shorter ends and less copper loss; (8) The rotor odd-number teeth setting can make the single-side stator armature coil have harmonic complementarity, low harmonic content of magnetic flux and back electromotive force, and high sinusoidal waveform; (9) The electrical period of the cogging torque generated by the second stator is half of the electrical period of the cogging torque generated by the first stator, which can be combined with structural parameter optimization to effectively suppress the cogging torque. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of the motor of the present invention;

[0019] Figure 2 It is a structural schematic diagram of the first stator magnetic conductive core of the motor of the present invention;

[0020] Figure 3 It is a structural schematic diagram of the second stator core of the motor of the present invention;

[0021] Figure 4 It is a schematic diagram of the structure of the motor rotor of the present invention;

[0022] Figure 5 is a permanent magnet flux path diagram when the rotor angle of the motor of the present invention is β1;

[0023] Figure 6 is a permanent magnet flux path diagram when the rotor angle of the motor of the present invention is β2;

[0024] Figure 7 It is a schematic diagram of the demagnetization operation principle of the motor of the present invention;

[0025] Figure 8 It is a schematic diagram of the magnetization operation principle of the motor of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] See also Figures 1 to 8 , the present invention provides a technical solution:

[0028] Combination Figure 1 A double-stator decoupling hybrid excitation axial flux switching motor comprises a first stator 1, a second stator 3 and a rotor 2 which are coaxially mounted. The rotor 2 is located between the first stator 1 and the second stator 3 and has an air gap with the first stator 1 and the second stator 3. The first stator 1 comprises 6 alternatingly arranged permeable cores 4, 6 magnetic isolation blocks 9, 12 permanent magnets 5 and 6 armature coils 7. The second stator core 6 has 12 open slots evenly arranged along the circumferential direction. The rotor 3 is located between the first stator 1 and the second stator 2. The permeable core 4 and the magnetic isolation block 9 are placed in succession to form a stator disk. The axial magnetic field permanent magnet 5 is magnetized in parallel permanent magnet axial direction and the magnetization directions of adjacent permanent magnets 5 are opposite. The axial magnetic field permanent magnet 5 is arranged on the surface of the axial number one stator tooth 4-1. The axial magnetic field permanent magnet 5 is magnetized in the axial direction, and the magnetization directions of the axial magnetic field permanent magnets 5 on adjacent number one stator teeth 4-1 are opposite.

[0029] The first stator 1, the second stator 3 and the rotor 2 all adopt a salient pole structure, which is formed by laminating silicon steel sheets. The first stator 1 and the second stator 2 adopt an asymmetric structure, and an air gap is left between the rotor 2 and the first stator 1 and the second stator 3. The axial magnetic field permanent magnet 5 is only located on the first stator 1, is made of neodymium iron boron material, and adopts a parallel permanent magnet axial magnetization structure, and the magnetization directions of adjacent permanent magnets 5 are opposite. The present invention places the permanent magnet 5 and the excitation winding 8 on the two stators respectively, which is better for the heat dissipation and stability of the motor operation.

[0030] Combination Figure 2 The permeable core 4 of the first stator 1 includes two first stator teeth 4-1 and one middle tooth 4-2, which are connected via a stator yoke 4-3. A stator slot 4-4 is radially arranged between the first stator teeth 4-1 and the middle tooth 4-2.

[0031] Recombination Figure 3The second stator core 6 is evenly provided with 12 T-slots 6-1 along the circumferential direction, and the second stator tooth 6-2 is a double-tooth structure, and a parallel slot 6-3 is provided on the tooth. The stator core adopts a multi-tooth structure, which effectively reduces the size of the cogging torque.

[0032] The stator tooth No. 1 4-1 of the first stator 1 is a parallel tooth structure; the middle tooth 4-2 of the first stator 1 is a parallel tooth structure; the axial magnetic field permanent magnet 5 is a parallel permanent magnet structure; the magnetic isolation block 9 is a parallel structure; the stator tooth No. 2 6-2 of the second stator 3 has the same double tooth cross-section, and parallel slots 6-3 are provided in the double teeth.

[0033] The armature coil 7 is wound between the adjacent single teeth of the adjacent second stator tooth 6-2, and the excitation winding 8 is wound at the root of the second stator tooth 6-2; the placement space of the armature coil 7 is increased on the second stator 3, which improves the power density of the motor; the placement space of the excitation winding 8 is increased, and the magnetic adjustment range of the motor is improved. The armature coil 7 and the excitation winding 8 adopt centralized windings, which shortens the end length, reduces the amount of copper used, and reduces copper loss. The excitation winding 8 is only located on the second stator 3, and is wound at the root of the second stator tooth 6-2. The directions of the currents passing through the adjacent excitation windings are opposite.

[0034] Combination Figure 4 The rotor 2 includes a magnetic separator 2-2 and a rotor core No. 1 2-1 and a rotor core No. 2 2-3 symmetrically arranged on both sides of the magnetic separator 2-2. Each core includes 11 rotor teeth 2-4 and a magnetic bridge 2-5 connecting the rotor teeth 2-4. There are neither permanent magnets nor windings on the rotor 2, and the structure is simple and the operation is reliable. The asymmetric sector angles of the rotor teeth 2-4 on the rotor core No. 1 2-1 and the rotor core No. 2 2-3 are in opposite directions. The structure of the intermediate rotor can enable the motor to obtain the minimum moment of inertia and the optimal heat dissipation conditions. The two cores of the rotor 2 are separated by non-magnetic materials, which realizes the decoupling of the two stator magnetic circuits and greatly improves the fault-tolerant operation capability of the motor. The asymmetric sector angles of the rotor teeth on both sides are in opposite directions, which can improve the magnetic circuit saturation and reduce the cogging torque.

[0035] The concentrated armature coils 7 of the first stator 1 are wound on the adjacent number one stator tooth 4-1 of the adjacent conductive core 4, the six concentrated armature coils 7 are in three phases, and every two concentrated armature coils 7 are connected in series to form a phase winding; the concentrated armature coils 7 of the second stator 3 are wound between the adjacent single teeth of the adjacent number two stator teeth 6-2, the twelve concentrated armature coils 7 are in three phases, and every four concentrated armature coils 7 are connected in series to form a phase winding; the concentrated armature coils 7 directly opposite to each other on the first stator 1 and the second stator 3 are connected in series.

[0036] When the excitation current in the excitation winding 8 is zero, the air gap magnetic field is provided only by the permanent magnet 5. When the rotor 2 runs to the angle β1, its permanent magnet flux path is as follows: Figure 5The magnetic flux shown in the figure passes through the A1 winding from top to bottom in the direction of the arrow. When the rotor 2 runs to the angle β2, its permanent magnetic flux path is as follows: Figure 6 The magnetic flux shown passes through the A1 winding from bottom to top in the direction of the arrow. In the two positions, the magnetic flux of the A1 winding turns is the same but the polarity is opposite. When the rotor 3 rotates continuously, the magnetic flux of the turns changes periodically between the positive and negative maximum values, corresponding to the generation of an induced electromotive force with alternating amplitude and phase.

[0037] When the excitation current flowing through the excitation winding 7 is negative, Figure 7 As shown, the upper dotted line is the permanent magnet flux path, and the lower dotted line is the excitation flux path. The two pass through the armature coil 7 in different directions, generating induced potentials in opposite directions in the armature coil 7. Compared with the action of the permanent magnet alone, the electric excitation winding plays a demagnetizing role at this time; at the same rotor position, the direction of the excitation current is changed, that is, the excitation current passed through the excitation winding 7 is positive, as shown Figure 8 As shown, the excitation magnetic flux and the permanent magnetic flux pass through the armature coil 7 in the same direction, generating an induced potential in the same direction in the armature coil 7. Compared with the action of the permanent magnet alone, the electric excitation winding plays a magnetizing role. By adjusting the direction and magnitude of the excitation current, the excitation magnetic field can be changed, and the magnitude of the induced potential of the armature coil 7 can be adjusted, so that the motor can operate in a wide constant power speed regulation range.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A double-stator decoupling hybrid excitation axial flux switching motor, characterized in that: It comprises a first stator (1), a second stator (3) and a rotor (2) which are coaxially mounted, wherein the rotor (2) is located between the first stator (1) and the second stator (3) and an air gap is left between the rotor (2) and the first stator (1) and the second stator (3); The first stator (1) comprises 6 magnetic permeable cores (4), 12 axial magnetic field permanent magnets (5), 6 concentrated armature coils (7), and 6 magnetic isolation blocks (9); the magnetic permeable cores (4) and the magnetic isolation blocks (9) are placed in succession to form a stator disk, and the axial magnetic field permanent magnets (5) are magnetized in parallel permanent magnet axial directions, and adjacent permanent magnets (5) are magnetized in opposite directions; The second stator core (6) on the second stator (3) is provided with 12 T-shaped slots (6-1), the T-shaped slots (6-1) divide the second stator (3) into 12 second stator teeth (6-2) with a double-tooth structure, parallel slots (6-3) are provided between the double teeth of the second stator teeth (6-2), armature coils (7) are wound between adjacent single teeth of adjacent second stator teeth (6-2), and excitation windings (8) are wound around the roots of the second stator teeth (6-2); The rotor (2) comprises a magnetic separator (2-2) and a first rotor core (2-1) and a second rotor core (2-3) arranged on both sides of the magnetic separator (2-2); the first rotor core (2-1) and the second rotor core (2-3) each comprise 11 rotor teeth (2-4) and a magnetic conductive bridge (2-5) connecting the rotor teeth (2-4); the asymmetric sector angles of the rotor teeth (2-4) on the first rotor core (2-1) and the second rotor core (2-3) are in opposite directions.

2. A dual-stator decoupling hybrid excitation axial flux switching motor according to claim 1, characterized in that: The permeable magnetic core (4) comprises a number one stator tooth (4-1) and an intermediate tooth (4-2) on both sides, the bottom of the intermediate tooth (4-2) and the number one stator tooth (4-1) are connected via a stator yoke (4-3), and a stator slot (4-4) is radially arranged between the number one stator tooth (4-1) and the intermediate tooth (4-2).

3. The dual-stator decoupling hybrid excitation axial flux switching motor according to claim 1, characterized in that: The axial magnetic field permanent magnet (5) is arranged on the surface of the axial first stator tooth (4-1), and the axial magnetic field permanent magnet (5) is magnetized in the axial direction, and the axial magnetic field permanent magnets (5) on adjacent first stator teeth (4-1) are magnetized in opposite directions.

4. The dual-stator decoupling hybrid excitation axial flux switching motor according to claim 1, characterized in that: The excitation winding (8) is wound on the root of the second stator tooth (6-2), and the directions of current flowing into adjacent excitation windings (8) are opposite.

5. The dual-stator decoupling hybrid excitation axial flux switching motor according to claim 1, characterized in that: The first stator tooth (4-1) of the first stator (1) is a parallel tooth structure; the middle tooth (4-2) of the first stator (1) is a parallel tooth structure; the axial magnetic field permanent magnet (5) is a parallel permanent magnet structure; the magnetic isolation block (9) is a parallel structure; the second stator tooth (6-2) of the second stator (3) has two teeth with the same cross section, and parallel slots (6-3) are provided in the two teeth.

6. The dual-stator decoupling hybrid excitation axial flux switching motor according to claim 2, characterized in that: The concentrated armature coils (7) of the first stator (1) are wound on adjacent first stator teeth (4-1) of adjacent permeable magnetic cores (4), six concentrated armature coils (7) form three phases, and every two concentrated armature coils (7) are connected in series to form a phase winding; the concentrated armature coils (7) of the second stator (3) are wound between adjacent single teeth of adjacent second stator teeth (6-2), twelve concentrated armature coils (7) form three phases, and every four concentrated armature coils (7) are connected in series to form a phase winding; the concentrated armature coils (7) directly facing each other on the first stator (1) and the second stator (3) are connected in series.

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