CN114006489B - Direct-drive alternating-pole permanent magnet hub motor - Google Patents
Direct-drive alternating-pole permanent magnet hub motor Download PDFInfo
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- CN114006489B CN114006489B CN202111208299.6A CN202111208299A CN114006489B CN 114006489 B CN114006489 B CN 114006489B CN 202111208299 A CN202111208299 A CN 202111208299A CN 114006489 B CN114006489 B CN 114006489B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K1/00—Details of the magnetic circuit
- H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
- H02K1/22—Rotating parts of the magnetic circuit
- H02K1/27—Rotor cores with permanent magnets
- H02K1/2706—Inner rotors
- H02K1/272—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis
- H02K1/274—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets
- H02K1/2753—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets the rotor consisting of magnets or groups of magnets arranged with alternating polarity
- H02K1/278—Surface mounted magnets; Inset magnets
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K1/00—Details of the magnetic circuit
- H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
- H02K1/12—Stationary parts of the magnetic circuit
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K1/00—Details of the magnetic circuit
- H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
- H02K1/22—Rotating parts of the magnetic circuit
- H02K1/27—Rotor cores with permanent magnets
- H02K1/2786—Outer rotors
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K16/00—Machines with more than one rotor or stator
- H02K16/04—Machines with one rotor and two stators
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K3/00—Details of windings
- H02K3/04—Windings characterised by the conductor shape, form or construction, e.g. with bar conductors
- H02K3/28—Layout of windings or of connections between windings
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/64—Electric machine technologies in electromobility
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Permanent Magnet Type Synchronous Machine (AREA)
- Iron Core Of Rotating Electric Machines (AREA)
- Permanent Field Magnets Of Synchronous Machinery (AREA)
Abstract
The invention discloses a direct-drive alternating-pole permanent magnet hub motor which comprises an inner stator, an outer stator and an alternating-pole rotor positioned between the inner stator and the outer stator, wherein the inner stator and the outer stator are respectively formed by combining a plurality of stator modules; the alternating pole rotor comprises a plurality of modular iron cores, and a Spoke permanent magnet and a surface-mounted permanent magnet which are alternately arranged, wherein the Spoke permanent magnet is magnetized in an annular direction, the surface-mounted permanent magnet is magnetized in a radial direction, positioning holes are formed in the modular iron cores, non-magnetic pressing plates are arranged on the inner side and the outer side of the alternating pole rotor, and the non-magnetic pressing plates and the positioning holes in the modular iron cores are fixed through positioning bolts. The invention solves the problem of back electromotive force even harmonic caused by asymmetric air gap flux density of the alternating pole permanent magnet motor, improves the waveform quality of the back electromotive force of the motor, improves the electromagnetic torque characteristic of the motor, solves the problem of single-side magnetic flux leakage of a single-stator Spoke rotor structure, and improves the permanent magnet utilization rate.
Description
Technical Field
The invention belongs to the field of motors, and particularly relates to a direct-drive alternating-pole permanent magnet hub motor.
Background
Because the low-speed high-torque direct-drive motor omits a speed reducer, the overall volume of the system is reduced, and the low-speed high-torque direct-drive motor has a very wide application prospect in the fields of new energy electric vehicles, wind power generation, ship propulsion, industrial production and the like. In order to save rare earth permanent magnet materials, the rare earth-less alternating pole permanent magnet motor is widely concerned. However, for an alternating-pole permanent magnet motor with odd unit motor stator teeth such as 9 slots and 10 poles, even harmonics in air gap magnetic density can cause counter potential even harmonics in a phase winding, and when three-phase alternating current is introduced into the motor, large odd-order torque pulsation can be generated to affect the electromagnetic torque quality of the motor.
Disclosure of Invention
In order to solve the technical problems mentioned in the background technology, the invention provides a direct-drive alternating-pole permanent magnet hub motor, which solves the problem of back electromotive force even harmonic caused by asymmetric air gap flux density of the alternating-pole permanent magnet hub motor, improves the waveform quality of the back electromotive force of the motor, and improves the electromagnetic torque characteristic of the motor.
In order to achieve the technical purpose, the technical scheme of the invention is as follows:
a direct-drive alternating-pole permanent magnet hub motor comprises an inner stator, an outer stator and an alternating-pole rotor positioned between the inner stator and the outer stator, wherein the inner stator and the outer stator respectively form independent air gaps with the alternating-pole rotor; the alternating pole rotor comprises a plurality of modular iron cores, and a Spoke permanent magnet and a surface-mounted permanent magnet which are alternately arranged, wherein the Spoke permanent magnet is magnetized in an annular direction, the surface-mounted permanent magnet is magnetized in a radial direction, positioning holes are formed in the modular iron cores, non-magnetic pressing plates are arranged on the inner side and the outer side of the alternating pole rotor, and the non-magnetic pressing plates and the positioning holes in the modular iron cores are fixed through positioning bolts.
Based on the preferable scheme of the technical scheme, the number of the stator teeth of the inner stator is the same as that of the stator teeth of the outer stator, the inner stator and the outer stator are arranged in a tooth-tooth opposite mode in space, the inner stator and the outer stator are respectively formed by combining 3n stator modules, each stator module comprises 9 stator teeth, counter potential even-order harmonics in a single-module phase winding are eliminated through synthesis of the 3n stator modules, and n is a positive integer.
Based on the preferable scheme of the technical scheme, for one outer stator module, 9 stator teeth of the outer stator module are sequentially wound with A-, A +, A-, C-, C +, C-, B-, B +, B-coils along the anticlockwise direction; for the inner stator module corresponding to the outer stator module space, 9 stator teeth of the inner stator module are wound with A +, A-, A +, C +, B +, B-, and B + coils in turn along the anticlockwise direction.
Based on the preferable scheme of the technical scheme, the number of the Spoke permanent magnets is 10n, and the number of the surface-mounted permanent magnets is 20n.
Based on the preferable scheme of the technical scheme, the modularized iron cores are H-shaped, the Spoke permanent magnets are arranged between the adjacent modularized iron cores, and the surface-mounted permanent magnets are arranged in the grooves of the modularized iron cores.
Based on the preferable scheme of the technical scheme, the magnetizing directions of the adjacent Spoke permanent magnets are opposite circumferentially; the magnetizing directions of the circumferentially adjacent surface-mounted permanent magnets are opposite in the radial direction, and the magnetizing directions of the radially opposite surface-mounted permanent magnets are also opposite.
Based on the preferable scheme of the technical scheme, the Spoke permanent magnet and the surface-mounted permanent magnet are made of neodymium iron boron and/or ferrite materials.
Based on the preferable scheme of the technical scheme, the modular iron core is formed by laminating silicon steel sheets, or three-dimensional identical SMC materials are adopted.
Based on the preferable scheme of the technical scheme, the armature winding adopts a centralized winding.
Based on the preferable scheme of the technical scheme, the inner stator and the outer stator are controlled as a motor; or the inner stator and the outer stator are respectively controlled as two motors, and the two motors simultaneously operate as a motor, a generator or a generator.
Adopt the beneficial effect that above-mentioned technical scheme brought:
the invention can eliminate counter potential even harmonic in the phase winding of the single module by adopting the synthesis of the stator module, and reduce the electromagnetic torque pulsation after the motor is electrified. The rotor side adopts the structure that the Spoke permanent magnets and the surface-mounted permanent magnets are alternately arranged, so that the consumption of the permanent magnets can be saved and the cost of the motor can be reduced compared with the traditional permanent magnet motor. The magnetic flux collecting device has the magnetic flux collecting advantage of the Spoke permanent magnet structure, solves the problem of single-side magnetic flux leakage of the single-stator Spoke permanent magnet structure, and improves the permanent magnet utilization rate. The rotor and the stator can be processed and assembled in a modularized mode, processing and assembling processes can be simplified, working efficiency is improved, and production cost is saved. The inner stator and the outer stator can work as a motor, two sets of windings of the inner stator and the outer stator can be separately controlled, and multiple working modes of electromotion and power generation are realized simultaneously.
Drawings
FIG. 1 is a schematic view of the motor structure of the present invention;
FIG. 2 is a three-dimensional exploded view of the present invention and a rotor assembly fixture;
FIG. 3 is a schematic diagram of the winding connections of the present invention;
FIG. 4 is a no-load back emf waveform of the motor inner stator motor and its three stator modules of the present invention;
FIG. 5 is a harmonic content plot of the no-load back emf waveforms of the motor inner stator motor and its three stator modules of the present invention;
FIG. 6 is a no-load back emf waveform of the motor outer stator motor and its three stator modules of the present invention;
FIG. 7 is a harmonic content plot of the no-load back emf waveforms of the motor outer stator motor and its three stator modules of the present invention;
fig. 8 is a no-load back electromotive force waveform diagram of the motor and the inner and outer stator motors of the invention.
Detailed Description
The technical scheme of the invention is explained in detail in the following with the accompanying drawings.
The invention designs a direct-drive alternating-pole permanent magnet hub motor, which comprises an inner stator 2, an outer stator 1 and an alternating-pole rotor 3 positioned between the inner stator and the outer stator, wherein the inner stator 2 and the outer stator 1 and the alternating-pole rotor 3 form independent air gaps 4 and 5 respectively, armature windings 1-3 and 2-3 are wound on each stator tooth of the inner stator 2 and the outer stator 1, the alternating-pole rotor 3 comprises a plurality of modular iron cores 3-1, and alternately arranged Spoke permanent magnets 3-3 and surface-mounted permanent magnets 3-4, the Spoke permanent magnets 3-3 adopt toroidal magnetization, the surface-mounted permanent magnets 3-4 adopt radial magnetization, and positioning holes 3-2 are arranged on the modular iron cores 3-1. As shown in fig. 2, the inner and outer sides of the alternating-pole rotor are provided with non-magnetic pressing plates 6, and the non-magnetic pressing plates 6 are fixed with the positioning holes 3-2 on the modular iron core 3-1 through positioning bolts.
In the embodiment, the inner stator and the outer stator are both composed of 27 stator teeth, each 9 teeth is a stator module, and each stator module is provided with a three-phase winding. The outer stator modules 1-4, 1-5 and 1-6 are respectively arranged opposite to the teeth-teeth on the space of the inner stator modules 2-4, 2-5 and 2-6, the synthesis of the outer stator modules 1-4, 1-5 and 1-6 can eliminate the counter potential even harmonic in the single module phase winding, and the synthesis of the inner stator modules 2-4, 2-5 and 2-6 can also eliminate the counter potential even harmonic in the single module phase winding. Compared with the traditional alternating-pole motor structure, the motor structure can eliminate even harmonics in counter electromotive force, so that the quality of the electromagnetic torque of the motor is improved.
The winding connection mode of the motor is described with reference to fig. 3, taking a three-phase armature winding as an example, taking an outer stator module 1-4 as an example, 9 teeth on the stator are defined as teeth 1 to 9 in the counterclockwise direction, teeth 1 to 9 are respectively wound with a-, a +, a-, C-, B +, B-coils, meanwhile, 9 teeth on an inner stator module 2-4 are respectively wound with a teeth 10 to 18 in the counterclockwise direction, and teeth 10 to 18 are respectively wound with a +, a-, a +, C-, B +, B-, B + coils. The winding method of coils on other inner stator modules and other outer stator modules is respectively identical to that of the stator modules 2-4 and 1-4. The negative coil is defined as the current of the wire on the right side of the stator tooth as the outflow direction, and the positive coil is defined as the current of the wire on the right side of the stator tooth as the inflow direction.
In this embodiment, it is preferable that the number of the Spoke permanent magnets is 10 and the number of the surface-mount permanent magnets is 20. The modularized iron cores are H-shaped, the Spoke permanent magnets are arranged between the adjacent modularized iron cores, and the surface-mounted permanent magnets are arranged in the grooves of the modularized iron cores. The magnetizing directions of the adjacent Spoke permanent magnets are opposite circumferentially; the magnetizing directions of the circumferentially adjacent surface-mounted permanent magnets are opposite in the radial direction, and the magnetizing directions of the radially opposite surface-mounted permanent magnets are also opposite. The Spoke permanent magnet and the surface-mounted permanent magnet are made of neodymium iron boron and/or ferrite materials. The modular iron core is formed by laminating silicon steel sheets or adopts three-dimensional identical SMC materials.
In this embodiment, it is preferable that the armature winding is a concentrated winding. The inner stator and the outer stator are used as a motor to control; or the inner stator and the outer stator are respectively controlled as two motors, and the two motors simultaneously operate as a motor, a generator or a generator.
Fig. 4 and 6 are respectively idle-load back electromotive force waveforms of the inner stator and the outer stator of the direct-drive alternating-pole permanent magnet hub motor and three stator modules thereof, and it can be known from the diagrams that the idle-load back electromotive force waveforms of the inner stator module and the outer stator module are distorted, but the idle-load back electromotive force waveform quality of the inner stator motor and the outer stator motor is improved after the stator modules are synthesized. Fig. 5 and 7 are diagrams of harmonic analysis of no-load back electromotive force waveforms of the inner stator and the outer stator of the direct-drive alternating-pole permanent magnet hub motor and three stator modules thereof, which show that the no-load back electromotive force waveforms of the inner stator module and the outer stator module both contain a large amount of even harmonics, but even harmonics in a single stator module can be completely eliminated after the 3 inner stator modules and the 3 outer stator modules are synthesized, so that the design of a high-performance alternating-pole permanent magnet motor is realized.
Fig. 8 shows the no-load back electromotive force waveforms of the inner stator motor and the outer stator motor of the direct-drive alternating-pole permanent magnet hub motor and the synthesized no-load back electromotive force waveforms, wherein the inner stator motor and the outer stator motor are in the same phase, and therefore two sets of windings of the inner stator motor and the outer stator motor can be used as a motor to be controlled. Meanwhile, the two sets of windings of the inner stator motor and the outer stator motor can be independently controlled to simultaneously realize various working modes such as electromotion, power generation and the like.
The above embodiments are only for illustrating the technical idea of the present invention, and the protection scope of the present invention cannot be limited thereby, for example, the alternating pole rotor may have various structures, the radial magnetizing tile-shaped permanent magnet may be replaced by a V-shaped structure, a Halbach structure, etc., and the idea may also be extended to various motors, such as axial flux and linear motors, etc., and any modification made on the basis of the technical scheme according to the technical idea of the present invention falls within the protection scope of the present invention.
Claims (7)
1. A direct-drive alternating-pole permanent magnet hub motor is characterized by comprising an inner stator, an outer stator and an alternating-pole rotor positioned between the inner stator and the outer stator, wherein the inner stator and the outer stator respectively form independent air gaps with the alternating-pole rotor; the alternating pole rotor comprises a plurality of modular iron cores, and a Spoke permanent magnet and a surface-mounted permanent magnet which are alternately arranged, wherein the Spoke permanent magnet is magnetized in a circumferential direction, the surface-mounted permanent magnet is magnetized in a radial direction, positioning holes are formed in the modular iron cores, non-magnetic pressing plates are arranged on the inner side and the outer side of the alternating pole rotor, and the non-magnetic pressing plates and the positioning holes in the modular iron cores are fixed through positioning bolts;
the stator teeth of the inner stator and the outer stator are the same, the inner stator and the outer stator are arranged in a tooth-tooth opposite mode in space, the inner stator and the outer stator are formed by combining 3n stator modules respectively, each stator module comprises 9 stator teeth, counter potential even-order harmonics in a single-module phase winding are eliminated through synthesis of the 3n stator modules, and n is a positive integer;
for an outer stator module, 9 stator teeth of the outer stator module are wound with A-, A +, A-, C-, C +, C-, B-, B + and B-coils in turn along the anticlockwise direction; for the inner stator module corresponding to the outer stator module space, 9 stator teeth of the inner stator module are wound with A +, A-, A +, C +, B +, B-, B + coils in turn along the anticlockwise direction;
the magnetizing directions of the adjacent Spoke permanent magnets are opposite circumferentially; the magnetizing directions of the circumferentially adjacent surface-mounted permanent magnets are opposite in the radial direction, and the magnetizing directions of the radially opposite surface-mounted permanent magnets are also opposite.
2. The direct-drive alternating pole permanent magnet hub motor of claim 1, wherein the number of Spoke permanent magnets is 10n, and the number of surface-mounted permanent magnets is 20n.
3. The direct-drive alternating pole permanent magnet hub motor of claim 1, wherein the modular cores are "H" shaped, the Spoke permanent magnets are disposed between adjacent modular cores, and the surface-mount permanent magnets are disposed in slots of the modular cores.
4. The direct-drive alternating pole permanent magnet hub motor as recited in claim 1, wherein said Spoke permanent magnets and said surface-mount permanent magnets are made of neodymium iron boron and/or ferrite materials.
5. The direct-drive alternating-pole permanent magnet hub motor as claimed in claim 1, wherein the modular iron core is formed by laminating silicon steel sheets or three-dimensionally isotropic SMC (sheet molding compound) materials.
6. The direct drive alternating pole permanent magnet wheel hub motor as in claim 1, wherein said armature windings are concentrated windings.
7. The direct drive alternating pole permanent magnet hub motor as in claim 1, wherein the inner and outer stators are controlled as one motor; or the inner stator and the outer stator are respectively controlled as two motors, and the two motors simultaneously operate as a motor, a generator or a generator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111208299.6A CN114006489B (en) | 2021-10-18 | 2021-10-18 | Direct-drive alternating-pole permanent magnet hub motor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111208299.6A CN114006489B (en) | 2021-10-18 | 2021-10-18 | Direct-drive alternating-pole permanent magnet hub motor |
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| Publication Number | Publication Date |
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| CN114006489A CN114006489A (en) | 2022-02-01 |
| CN114006489B true CN114006489B (en) | 2023-03-24 |
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| CN202111208299.6A Active CN114006489B (en) | 2021-10-18 | 2021-10-18 | Direct-drive alternating-pole permanent magnet hub motor |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116094272B (en) * | 2023-03-09 | 2024-04-16 | 山东大学 | Two-degree-of-freedom motor based on modularized movable rotor and working method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2013143805A (en) * | 2012-01-10 | 2013-07-22 | Toyota Motor Corp | Rotor of rotary electric machine, and rotary electric machine with the same |
| CN108599418B (en) * | 2018-05-16 | 2020-05-19 | 华中科技大学 | Rotor core of magnetic circuit series type hybrid permanent magnet controllable flux motor and motor |
| CN111277092B (en) * | 2020-02-17 | 2021-05-11 | 南京航空航天大学 | Stator modularized double-rotor alternating pole permanent magnet motor |
| CN111313576B (en) * | 2020-04-02 | 2021-07-06 | 南京航空航天大学 | Modularized permanent magnet motor |
| CN111541325B (en) * | 2020-04-30 | 2021-11-23 | 南京理工大学 | Axial magnetic field permanent magnet motor combined magnetizing type permanent magnet built-in rotor |
| CN111478470A (en) * | 2020-05-11 | 2020-07-31 | 浙江龙芯电驱动科技有限公司 | Permanent magnet synchronous motor with double-armature radial magnetic circuit structure |
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