Stator permanent magnet type rotor skewed slot magnetic flux switching motor

Abstract

The invention discloses a stator permanent magnet type rotor skewed slot magnetic flux switching motor which comprises a motor stator which comprises a stator iron core, a plurality of main teeth and a plurality of auxiliary teeth are arranged on the inner side of the stator iron core in the circumferential direction at intervals in a staggered mode, and the number of the main teeth is the same as that of the auxiliary teeth; each main tooth and the adjacent auxiliary tooth form a wire embedding groove, a coil winding is arranged in each wire embedding groove, each main tooth is provided with a first set of permanent magnets, the end part of each auxiliary tooth is provided with a pole shoe, and the pole shoe is provided with a second set of permanent magnets; the motor rotor and the motor stator are coaxially arranged, a plurality of rotor teeth are arranged on the outer side of the motor rotor in the circumferential direction at intervals, and the number of the rotor teeth is an even number. According to the invention, the torque of the motor is improved, and the motor is suitable for application occasions with higher torque requirements under the same volume.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a stator permanent magnet rotor skew slot flux switching motor. Background Art

[0002] As an advanced motor design, the permanent magnet flux switching motor (FSPM) has attracted extensive attention from academia and industry in recent years due to its unique advantages and wide application potential. The permanent magnet flux switching motor has a simple structure, a strong air gap magnetic field, and can generate large torque and power in a small volume. It is particularly suitable for occasions with strict restrictions on motor size and weight, such as electric vehicles, low-altitude aircraft, and robot joints. However, the disadvantage is that the magnetic field structure and working principle of the permanent magnet flux switching motor are relatively complex, and the control strategy and control system of the motor are required to be high. In addition, the motor may generate large torque pulsation during operation, which will not only cause mechanical vibration and noise, but also affect the running stability and control accuracy of the motor.

[0003] Figure 1 A conventional E-type structure stator permanent magnet flux switching motor is shown, which includes a motor stator and a motor rotor, wherein the motor stator and the motor rotor are coaxially arranged; the motor stator includes a stator core, and the inner side of the stator core is staggered with six main teeth and six auxiliary teeth at intervals, and the six main teeth and the six auxiliary teeth form twelve wire-embedded slots, and the three-phase coil winding is installed in the twelve wire-embedded slots by a single-layer winding method, and permanent magnets are arranged on the six main teeth; fourteen rotor teeth are arranged at intervals on the outer side of the motor rotor. Although the conventional E-type structure stator permanent magnet flux switching motor has the advantages of small size and large torque, its torque still cannot meet the requirements in some high torque demand occasions, resulting in that the motor may not be able to provide sufficient driving force in some heavy-load or high power output applications; at the same time, since the number of salient poles of its motor rotor is an even number and there are even harmonics, the torque pulsation is also relatively large. Summary of the invention

[0004] In order to overcome the problems of insufficient torque and large torque pulsation in the permanent magnet type flux switching motor in the prior art, the present invention provides a stator permanent magnet type rotor skew slot flux switching motor.

[0005] The technical solution of the present invention is as follows:

[0006] A stator permanent magnet rotor skew slot flux switching motor, comprising:

[0007] A motor stator, comprising a stator core, wherein a plurality of main teeth and a plurality of auxiliary teeth are arranged at staggered intervals in the circumferential direction on the inner side of the stator core, the number of the main teeth is the same as the number of the auxiliary teeth, each of the main teeth forms a wire embedding groove with an adjacent auxiliary tooth, a coil winding is arranged in the wire embedding groove, each of the main teeth is provided with a first set of permanent magnets, and each of the auxiliary teeth is provided with a pole shoe at the end thereof, and a second set of permanent magnets is arranged on the pole shoe;

[0008] The motor rotor is coaxially arranged with the motor stator, and a plurality of rotor teeth are arranged at intervals in the circumferential direction on the outer side of the motor rotor, and the number of the rotor teeth is an even number.

[0009] According to the stator permanent magnet rotor skew slot flux switching motor of the above scheme, the motor rotor is formed by stacking a plurality of motor rotor segments with different rotation angles, and the motor rotor segments are formed by stacking silicon steel sheets.

[0010] Furthermore, the motor rotor is formed by laminating two motor rotor segments with different rotation angles.

[0011] According to the stator permanent magnet rotor skew slot flux switching motor of the above scheme, the first set of permanent magnets are tangentially magnetized permanent magnets.

[0012] According to the stator permanent magnet rotor skew slot flux switching motor of the above solution, a first set of permanent magnet mounting grooves for mounting the first set of permanent magnets are provided on the main teeth.

[0013] Furthermore, a magnetic bridge matching with the first set of permanent magnets is provided at the bottom of the first set of permanent magnet installation grooves.

[0014] According to the stator permanent magnet rotor skew slot flux switching motor of the above solution, a pair of the second set of permanent magnets is arranged on the pole shoe of each auxiliary tooth.

[0015] Furthermore, the pole shoe is T-shaped, and two sides thereof respectively form a second set of permanent magnet mounting grooves for mounting the second set of permanent magnets.

[0016] According to the stator permanent magnet rotor skew slot flux switching motor of the above solution, the coil winding is a single-layer coil winding.

[0017] According to the stator permanent magnet rotor skew slot flux switching motor of the above scheme, the number of the main teeth and the number of the auxiliary teeth are both six, and the number of the rotor teeth is fourteen.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. By setting a pole shoe at the end of each auxiliary tooth and setting a second set of permanent magnets at the pole shoe of each auxiliary tooth, the torque of the motor is improved compared with the traditional E-type stator permanent magnet flux switching motor through MAXWELL finite element analysis, which is suitable for applications with higher torque requirements under the same volume;

[0020] 2. The motor torque pulsation is controlled within an acceptable range by means of the rotor stepped segmented skew slots, so as to improve the running stability and control accuracy of the motor;

[0021] 3. By arranging the first set of permanent magnet mounting grooves and magnetic bridges on the main teeth, it is convenient to fix the first set of permanent magnets for tangential magnetization to the main teeth, which is convenient for processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a schematic diagram of the structure of a traditional E-type stator permanent magnet flux switching motor;

[0024] Figure 2 It is a structural schematic diagram of a stator permanent magnet rotor skew slot flux switching motor in one embodiment of the present invention;

[0025] Figure 3 It is a structural schematic diagram of a stator core in one embodiment of the present invention;

[0026] Figure 4 It is a partial schematic diagram of the bottom of the first set of permanent magnet mounting grooves in one embodiment of the present invention.

[0027] In the figure,

[0028] 1. Motor stator; 11. Stator core; 12. Main teeth; 121. First set of permanent magnet mounting slots; 122. Magnetic bridge; 13. Auxiliary teeth; 131. Pole shoes; 1311. Second set of permanent magnet mounting slots; 14. Wire embedding slots; 15. Coil windings; 16. First set of permanent magnets; 17. Second set of permanent magnets; 2. Motor rotor; 21. Rotor teeth. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. It is also stated that the embodiments described below are only used to explain the present invention and are not used to limit the present invention.

[0030] It should be noted that the terms "install", "set", "connect", "fix" and the like should be understood in a broad sense, for example, they can be fixedly connected, detachably connected, or integrated; they can be mechanically connected or electrically connected; they can be directly connected, or indirectly connected through an intermediate medium, or they can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. The indicated orientation or position relationship is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the application product is usually placed when in use, or the orientation or position relationship commonly understood by those skilled in the art, or the orientation or position relationship in which the application product is usually placed when in use. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The terms "first" and "second" are only used for the purpose of convenience of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0031] Figure 1 A traditional E-type structure stator permanent magnet flux switching motor is shown, which includes a motor stator 1 and a motor rotor 2. The motor stator 1 and the motor rotor 2 are coaxially arranged; the motor stator 1 includes a stator core 11, and the inner side of the stator core 11 is circumferentially staggered with six main teeth 12 and six auxiliary teeth 13. The six main teeth 12 and the six auxiliary teeth 13 form twelve wire-embedded grooves 14, and the twelve wire-embedded grooves 14 are provided with corresponding coil windings 15. The six main teeth 12 are all provided with a first set of permanent magnets 16; the outer side of the motor rotor 2 is circumferentially spaced with fourteen rotor teeth 21, and the motor rotor 2 has neither windings nor permanent magnets. The auxiliary teeth 13 can be matched with the rotor teeth 21 with different rotors to design the motor. Figure 1 In the figure, A+ represents the incoming wire of the A-phase coil winding, A- represents the outgoing wire of the A-phase coil winding, B+ represents the incoming wire of the B-phase coil winding, B- represents the outgoing wire of the B-phase coil winding, C+ represents the incoming wire of the C-phase coil winding, and C- represents the outgoing wire of the C-phase coil winding.

[0032] The above-mentioned E-type structure stator permanent magnet flux switching motor has the advantages of simple structure, small size and large torque, but in some occasions with high torque requirements, its torque still cannot meet the requirements, resulting in that the motor may not be able to provide sufficient driving force in some heavy-load applications or applications requiring high power output; at the same time, since the number of salient poles of its motor rotor 2 is an even number and there are even harmonics, the torque pulsation is also relatively large.

[0033] To solve the above problems, please refer to Figure 2 The embodiment of the present invention provides a stator permanent magnet rotor skew slot flux switching motor, comprising a motor stator 1 and a motor rotor 2, wherein the motor stator 1 and the motor rotor 2 are coaxially arranged. The motor stator 1 comprises a stator core 11, wherein a plurality of main teeth 12 and a plurality of auxiliary teeth 13 are arranged at staggered intervals in the inner circumferential direction of the stator core 11, and the number of the main teeth 12 is the same as the number of the auxiliary teeth 13. Each main tooth 12 forms a wire embedding groove 14 with an adjacent auxiliary tooth 13, wherein a coil winding 15 is arranged in the wire embedding groove 14, and the coil winding 15 of each wire embedding groove 14 is a single-layer coil winding. A first set of permanent magnets 16 is arranged on each main tooth 12, and a pole shoe 131 is arranged at the end of each auxiliary tooth 13, and a second set of permanent magnets 17 is arranged on the pole shoe 131. A plurality of rotor teeth 21 are arranged at intervals in the circumferential direction on the outer side of the motor rotor 2, and the number of the rotor teeth 21 is an even number.

[0034] The above-mentioned stator permanent magnet rotor skew slot flux switching motor, by arranging a pole shoe 131 at the end of each auxiliary tooth 13, and arranging a second set of permanent magnets 17 at the pole shoe 131 of each auxiliary tooth 13, through MAXWELL finite element analysis, compared with the traditional E-type structure stator permanent magnet flux switching motor, the torque of the motor is improved, which is suitable for applications with higher torque requirements under the same volume.

[0035] In one embodiment, the motor rotor 2 is formed by stacking multiple motor rotor segments with different rotation angles, and the motor rotor segments are stacked by silicon steel sheets, that is, after the silicon steel sheets of the first rotor segment are stacked, the silicon steel sheets of the second rotor segment are stacked at a staggered angle. Since the number of rotor teeth 21 of the motor rotor 2 is an even number and there are even harmonics, the torque pulsation is also relatively large. Therefore, this embodiment controls the motor torque pulsation within an acceptable range by means of a rotor stepped segmented chute to improve the running stability and control accuracy of the motor. After the motor rotor 2 adopts a stepped segmented chute, the electromagnetic torque and induced electromotive force formed can effectively weaken the harmonic electromotive force generated by the tooth harmonic magnetic field, thereby weakening the additional torque caused by these harmonic magnetic fields. Preferably, the motor rotor 2 is divided into two sections, that is, the motor rotor section of the first section is stacked with the motor rotor section of the second section at a certain angle, and the torque pulsation can be reduced to less than 20%. It should be understood that in other embodiments, the motor rotor 2 may also be formed by stacking three or more motor rotor segments with different rotation angles. However, the more motor rotor segments there are, the more difficult the processing of the motor rotor 2 will be, and the higher the production and processing cost will be.

[0036] In one embodiment, all unit structures in the motor stator 1 are closely assembled together. The close assembly design makes the motor stator 1 highly compact in both radial and axial directions, helps to reduce the overall volume and weight of the motor, and simplifies the manufacturing process of the motor.

[0037] In one embodiment, the first set of permanent magnets 16 are tangentially magnetized permanent magnets. The magnetization direction of the tangentially magnetized permanent magnets is parallel to one side surface (usually the circumferential surface) of the permanent magnet, that is, the magnetization direction is tangential to the circumference of the permanent magnet, so that the first set of permanent magnets 16 generates a higher magnetic flux density in the air gap; in addition, since the magnetization direction is parallel to the direction of motion (or current direction), the magnetic field generated by the tangentially magnetized permanent magnets is more evenly distributed, which helps to reduce leakage flux and magnetic resistance, thereby improving the performance and efficiency of the motor.

[0038] In one embodiment, the second set of permanent magnets 17 are tangentially magnetized permanent magnets. The magnetization direction of the tangentially magnetized permanent magnets is parallel to one side surface (usually the circumferential surface) of the permanent magnet, that is, the magnetization direction is tangential to the circumference of the permanent magnet, so that the second set of permanent magnets 17 generates a higher magnetic flux density in the air gap; in addition, since the magnetization direction is parallel to the direction of motion (or current direction), the magnetic field generated by the tangentially magnetized permanent magnets is more evenly distributed, which helps to reduce leakage flux and magnetic resistance, thereby improving the performance and efficiency of the motor.

[0039] See also Figure 3 , Figure 4In one embodiment, the main teeth 12 are provided with first set of permanent magnet installation grooves 121 for installing the first set of permanent magnets 16, and the bottom of the first set of permanent magnet installation grooves 121 is provided with magnetic bridges 122 that match the first set of permanent magnets 16. The provision of the first set of permanent magnet installation grooves 121 ensures that the first set of permanent magnets 16 can be accurately and stably installed on the main teeth 12. The shape, size and position of the first set of permanent magnet installation grooves 121 are carefully calculated to match the size and shape of the first set of permanent magnets 16, thereby avoiding excessive gaps or misalignment during the installation process. In addition, by setting a magnetic bridge 122 at the bottom of the first set of permanent magnet mounting grooves 121, the magnetic bridge 122 not only serves as a part of the magnetic circuit, but also plays a role in fixing and supporting the first set of permanent magnets 16, ensuring the stability of the permanent magnets in the first set of permanent magnet mounting grooves 121, preventing the permanent magnets from falling off due to vibration or centrifugal force during the operation of the motor, and can significantly reduce the processing difficulty of installing and fixing the first set of permanent magnets 16 on the main teeth 12, thereby reducing production costs and improving production efficiency.

[0040] See also Figure 2 In one embodiment, a pair of second permanent magnets 17 are provided on the pole shoe 131 of each auxiliary tooth 13. By providing a pair of second permanent magnets 17 on the pole shoe 131 of each auxiliary tooth 13, the second permanent magnets 17 play a supplementary and reinforcing role in the magnetic circuit of the motor, which helps to improve the magnetic field strength and performance of the motor. By reasonably configuring the number and position of the second permanent magnets 17, the magnetic field distribution of the motor can be further optimized, which helps to reduce leakage flux and magnetic resistance, and improve the efficiency and output power of the motor.

[0041] See also Figure 3 Furthermore, the pole shoe 131 is T-shaped, which helps to enhance the mechanical strength and stability of the pole shoe 131, and the T-shaped structure enables the pole shoe 131 to play a better guiding and focusing role in the magnetic circuit of the motor, which helps to optimize the distribution of the magnetic field. At the same time, the two sides of the pole shoe 131 respectively form a second set of permanent magnet mounting grooves 1311 for mounting the second set of permanent magnets 17. The setting of the second set of permanent magnet mounting grooves 1311 ensures that the second set of permanent magnets 17 can be accurately and stably mounted on the pole shoe 131 of the auxiliary tooth 13. The shape, size and position of the second set of permanent magnet mounting grooves 1311 are carefully calculated to match the size and shape of the second set of permanent magnets 17, so as to avoid excessive gaps or misalignments during the installation process.

[0042] See also Figure 2In a specific embodiment, the number of the main teeth 12 and the number of the auxiliary teeth 13 are both six, and the number of the rotor teeth 21 on the electronic rotor is fourteen. The six main teeth 12 and the six auxiliary teeth 13 form twelve wire-embedded grooves 14, and the twelve wire-embedded grooves 14 are provided with corresponding coil windings 15. The specific winding method is as follows Figure 2 As shown. Figure 2 In the figure, A+ represents the incoming wire of the coil winding of phase A, A- represents the outgoing wire of the coil winding of phase A, B+ represents the incoming wire of the coil winding of phase B, B- represents the outgoing wire of the coil winding of phase B, C+ represents the incoming wire of the coil winding of phase C, and C- represents the outgoing wire of the coil winding of phase C. The above winding method, by reasonably arranging the incoming and outgoing wires of the coil windings 15 of each phase, makes only the coil windings 15 of the same phase in one wire embedding slot 14, which not only requires less insulating material, but also simplifies the wire embedding process, making the winding method simpler during processing and more conducive to processing.

[0043] It should be noted that the present invention does not limit the number of main teeth 12 and auxiliary teeth 13, and the number of main teeth 12 and auxiliary teeth 13 only needs to be consistent; at the same time, the number of rotor teeth 21 on the motor rotor 2 is not limited, and the number of rotor teeth 21 can be an even number. Those skilled in the art can flexibly select the number of main teeth 12, auxiliary teeth 13 and rotor teeth 21 according to specific application requirements and the overall size of the motor under the above-mentioned restrictions, so that the motor can adapt to different working environments and performance requirements, thereby improving its versatility and practicality.

[0044] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

[0045] The above is an exemplary description of the present invention in conjunction with the accompanying drawings. It is obvious that the implementation of the present invention is not limited to the above-mentioned method. As long as various improvements are made by adopting the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A stator permanent magnet rotor skew slot flux switching motor, characterized in that: include: A motor stator, comprising a stator core, wherein a plurality of main teeth and a plurality of auxiliary teeth are arranged at staggered intervals in the circumferential direction on the inner side of the stator core, the number of the main teeth is the same as the number of the auxiliary teeth, each of the main teeth forms a wire embedding groove with an adjacent auxiliary tooth, a coil winding is arranged in the wire embedding groove, each of the main teeth is provided with a first set of permanent magnets, and each of the auxiliary teeth is provided with a pole shoe at the end thereof, and a second set of permanent magnets is arranged on the pole shoe; The motor rotor is coaxially arranged with the motor stator, and a plurality of rotor teeth are arranged at intervals in the circumferential direction on the outer side of the motor rotor, and the number of the rotor teeth is an even number.

2. The stator permanent magnet rotor skew slot flux switching motor according to claim 1, characterized in that: The motor rotor is formed by stacking a plurality of motor rotor segments with different rotation angles, and the motor rotor segments are formed by stacking silicon steel sheets.

3. The stator permanent magnet rotor skew slot flux switching motor according to claim 2, characterized in that: The motor rotor is formed by stacking two motor rotor segments with different rotation angles.

4. The stator permanent magnet rotor skew slot flux switching motor according to claim 1, characterized in that: The first set of permanent magnets are tangentially magnetized permanent magnets.

5. The stator permanent magnet rotor skew slot flux switching motor according to claim 1, characterized in that: The main teeth are provided with a first set of permanent magnet mounting grooves for mounting the first set of permanent magnets.

6. The stator permanent magnet rotor skew slot flux switching motor according to claim 5, characterized in that: The bottom of the first set of permanent magnet installation grooves is provided with a magnetic bridge that matches the first set of permanent magnets.

7. The stator permanent magnet rotor skew slot flux switching motor according to claim 1, characterized in that: A pair of the second set of permanent magnets is arranged on the pole shoe of each auxiliary tooth.

8. The stator permanent magnet rotor skew slot flux switching motor according to claim 7, characterized in that: The pole shoe is T-shaped, and two sides thereof are respectively formed with second sets of permanent magnet mounting grooves for mounting the second set of permanent magnets.

9. The stator permanent magnet rotor skew slot flux switching motor according to claim 1, characterized in that: The coil winding is a single-layer coil winding.

10. The stator permanent magnet rotor skew slot flux switching motor according to claim 1, characterized in that: The number of the main teeth and the number of the auxiliary teeth are both six, and the number of the rotor teeth is fourteen.

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