Single-polarity motor based on pole modulation and harmonic slot coordination optimization

Abstract

The application discloses a single-polarity motor based on magnetic pole modulation and harmonic slot cooperative optimization, which comprises a single-polarity rotor lamination, and the outer circumferential surface of the single-polarity rotor lamination is provided with alternating first magnetic poles and second magnetic poles; the polarities of the first magnetic poles and the second magnetic poles are opposite; the outer circumferences of the first magnetic poles are provided with first circular arcs; the outer circumferences of the second magnetic poles are provided with second circular arcs; the first circular arcs and the second circular arcs are concentrically arranged relative to the center of the single-polarity rotor lamination; the radius of the first magnetic poles is greater than the radius of the second magnetic poles; the motor efficiency is ensured by increasing the air gap reluctance under the condition that the effective area of the air gap magnetic flux does not change obviously; the amplitude of each order harmonic electromagnetic radial force caused by the rotor magnetic field is reduced, and the purpose of reducing the vibration noise of the motor is achieved. The motor has wide application prospects in the fields of new energy vehicles, aerospace, numerical control machine tools and the like, and can effectively improve the comfort and high-end quality of products.

Description

Technical Field

[0001] This invention relates to a unipolar motor based on the synergistic optimization of magnetic pole modulation and harmonic slots. Background Technology

[0002] With the continued advancement of the dual-carbon strategy, the development of high-efficiency and energy-saving motors has become an urgent need for industrial transformation and upgrading. To adapt to the development of key areas such as new energy vehicles and high-end manufacturing, motors need to meet higher requirements for high efficiency, low noise, and low cost. To improve the utilization rate of rare earth materials, existing technologies have developed a unipolar motor that can significantly reduce the amount of rare earth materials used. However, compared with traditional alternating pole permanent magnet motors (NS motors), unipolar motors face severe inherent challenges in vibration and noise control, stemming from integer-order spatial harmonics caused by the asymmetrical magnetic circuit structure.

[0003] Traditional alternating pole (NS) motors (with 2P permanent magnets) have a symmetrical air gap magnetic field and a high sinusoidal magnetic flux density waveform, with their main electromagnetic force wave components concentrated in low-order components (such as 2nd and 4th order). Although these low-order force waves have large amplitudes, their excitation frequencies are relatively low, and they can be effectively predicted and suppressed through mature slot-pole matching and stator-rotor tooth profile optimization techniques. However, unipolar motors (with P permanent magnets) employ a topology of alternating permanent magnet poles (N) and silicon steel poles (pseudo-S poles). The fundamental differences in permeability and magnetomotive force between permanent magnet poles and silicon steel poles cause severe distortion of the air gap magnetic flux density waveform, generating abundant odd-order and other integer-order spatial harmonics, leading to a surge in harmonic content. Furthermore, the interaction of these harmonics with the armature magnetic field excites electromagnetic radial force waves. Due to the widespread presence of harmonics and radial force waves, the vibration and noise levels of unipolar motors are generally significantly higher than those of alternating pole (NS) motors. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a unipolar motor based on the synergistic optimization of magnetic pole modulation and harmonic slot.

[0005] The present invention solves the above-mentioned technical problems through the following technical solution:

[0006] A unipolar motor based on the synergistic optimization of magnetic pole modulation and harmonic slots includes a unipolar rotor lamination. The unipolar rotor lamination has alternating first and second magnetic poles arranged in the circumferential direction. The first and second magnetic poles have opposite polarities. The outer periphery of the first magnetic pole has a first arc, and the outer periphery of the second magnetic pole has a second arc. The first and second arcs are concentrically arranged with respect to the center of the unipolar rotor lamination. The radius of the first magnetic pole is larger than the radius of the second magnetic pole.

[0007] In this design, compared to a conventional alternating pole motor with N / S permanent magnets, the unipolar rotor laminations only have permanent magnets of a single polarity. These permanent magnets are spaced apart on the unipolar rotor laminations, and they magnetize the iron core portions without permanent magnets into virtual poles of opposite polarity. This creates alternating first and second magnetic poles along the circumference of the rotor laminations, with the second pole having the opposite magnetic properties to the first pole. Therefore, the number of permanent magnets used in the unipolar rotor laminations is half that of a conventional N / S alternating pole motor, significantly reducing the number of permanent magnets required and improving economic efficiency. The outer circumferential arcs of the first and second magnetic poles are concentrically set with the center of the rotor laminations, and the radius of the first magnetic pole is larger than that of the second magnetic pole. Compared with the existing technology where unequal eccentric radii lead to a decrease in the effective magnetic flux in the air gap and a reduction in the average magnetic flux density, this setting can increase the air gap reluctance and ensure motor efficiency without significantly changing the effective area of ​​the air gap magnetic flux. Furthermore, it does not introduce additional harmonics. While ensuring the uniformity of the air gap magnetic flux of each pole of the motor, it reduces the amplitude of the electromagnetic radial forces of each order harmonic caused by the rotor magnetic field, thereby reducing motor vibration and noise.

[0008] Preferably, a first harmonic slot is provided on the first magnetic pole, and the distance between the bottom of the first harmonic slot and the center of the unipolar rotor lamination is set to be greater than or equal to 0.9 times the radius of the second magnetic pole. This can reduce the leakage flux coefficient of the motor, increase the main magnetic flux amplitude of the motor, improve the motor efficiency, optimize the direction of the magnetic lines of force, and improve the torque.

[0009] Preferably, the second magnetic pole has a second harmonic slot, and there are two second harmonic slots, which are spaced apart along the circumferential direction of the unipolar rotor lamination.

[0010] In this scheme, a second harmonic slot is provided on the second magnetic pole to suppress the harmonic amplitude generated at the second magnetic pole position. Preferably, two second harmonic slots are provided, and the two harmonic slots are spaced apart along the circumferential direction of the unipolar rotor lamination. This allows for fine modulation of the magnetic field, further reducing the amplitude of harmonics generated at the second magnetic pole position, thereby reducing torque ripple and ultimately achieving the goal of reducing noise.

[0011] Two harmonic slots can also optimize the magnetic field lines on the first magnetic pole, reduce the leakage flux coefficient of the motor, increase the main magnetic flux amplitude of the motor, and improve the motor efficiency.

[0012] Preferably, the distance between the two second harmonic slots along the circumferential direction of the unipolar rotor lamination is a first distance, and the central angle corresponding to the first distance in the unipolar rotor lamination is equal to the central angle corresponding to the first harmonic slot in the unipolar rotor lamination.

[0013] In this scheme, the two second harmonic slots are associated with the first harmonic slot, so that the three slots work together to reduce the amplitude of the harmonics generated by the first and second magnetic pole positions, thereby reducing torque fluctuations and thus reducing the vibration noise of the motor.

[0014] Preferably, the radius of the first magnetic pole The radius of the second magnetic pole The relationship is: .

[0015] In this scheme, optimizing the range of the second magnetic pole can significantly reduce the problem of magnetic flux density amplitude asymmetry and reduce motor torque fluctuation.

[0016] Preferably, the central angle corresponding to the first harmonic slot along the circumferential direction of the unipolar rotor lamination is... The range of values ​​is ,in, The central angle occupied by the first magnetic pole in the unipolar rotor lamination is given by [reference to angle]. The value is P represents the number of first magnetic poles.

[0017] In this scheme, the above-mentioned structural configuration can reduce the amplitude of electromagnetic radial force, thereby reducing the vibration and noise of the motor, guiding the magnetic circuit direction, and reducing the auxiliary magnetic flux.

[0018] Preferably, the end face of the unipolar rotor lamination has at least two magnetic slots, the at least two magnetic slots are spaced apart along the circumferential direction of the unipolar rotor lamination, the magnetic slots correspond to the first magnetic poles, the magnetic slots include a permanent magnet section located in the middle and magnetic isolation sections located at both ends of the magnetic slot, the two magnetic isolation sections are symmetrical with respect to the permanent magnet section, the permanent magnet section is used to install permanent magnets, and the magnetic isolation sections extend along the axial direction of the unipolar rotor lamination to form a first magnetic isolation hole.

[0019] In this design, the magnetic isolation section optimizes the direction of the magnetic field lines at both ends of the permanent magnet, extends the conduction path of the magnetic field lines, and avoids local magnetic field saturation. The first magnetic isolation hole can also be used to dissipate heat from the rotor laminations.

[0020] Preferably, each of the two ends of the second magnetic pole is provided with a second magnetic isolation hole, the second magnetic isolation hole is disposed close to the first magnetic isolation hole, the second magnetic isolation hole and the adjacent first magnetic isolation hole form a magnetic isolation bridge, the magnetic isolation bridge extends along the radial direction of the unipolar rotor lamination, the first magnetic pole and the adjacent second magnetic pole have an inter-pole center line, and the first magnetic isolation hole and the second magnetic isolation hole are symmetrically arranged with respect to the inter-pole center line.

[0021] In this design, the second magnetic isolation hole serves both to optimize the magnetic field lines at the second magnetic pole position and to dissipate heat from the rotor laminations. The magnetic isolation bridge forms the conduction path for the magnetic field lines, allowing them to be conducted along the bridge's extension direction and preventing magnetic leakage. The magnetic isolation bridge significantly reduces the motor's magnetic leakage coefficient, while its strength meets the rotor's rotational stress requirements.

[0022] Preferably, a third harmonic groove is provided on the outer peripheral surface of the unipolar rotor lamination, and the third harmonic groove is provided at the junction of the first magnetic pole and the second magnetic pole, and the third harmonic groove is symmetrical with respect to the center line between the poles.

[0023] In this scheme, the above-mentioned structural configuration can optimize the rotor's pole arc coefficient, thereby reducing the motor's leakage flux coefficient and torque fluctuation.

[0024] Preferably, the third harmonic slot forms an isosceles trapezoidal slot structure with a larger outer diameter and a smaller inner diameter. The isosceles trapezoidal slot structure includes a short base and a long base, and the central angle corresponding to the short base in the unipolar rotor lamination is... The range of values ​​is The central angle corresponding to the long base in the unipolar rotor lamination The range of values ​​is ,in, The central angle occupied by the first magnetic pole in the unipolar rotor lamination is given by [reference to angle]. The value is P represents the number of first magnetic poles.

[0025] In this scheme, the above-mentioned structural configuration is used to optimize the rotor's pole arc coefficient, thereby reducing the motor's leakage flux coefficient and torque fluctuation.

[0026] Preferably, the central angle occupied by the first magnetic isolation hole, the second magnetic isolation hole, and the magnetic isolation bridge in the circumferential direction of the unipolar rotor lamination is... The range of values ​​is .

[0027] In this scheme, the above-mentioned structural setting is adopted to optimize the magnetic field lines at the junction of the first and second magnetic poles, prevent local magnetic flux saturation, prevent inter-pole magnetic leakage, increase the main magnetic flux amplitude of the motor, and improve motor efficiency.

[0028] Preferably, the thickness of the magnetic isolation bridge along the circumferential direction of the unipolar rotor lamination is... The value range is 0.4mm < ≤0.5mm.

[0029] In this solution, the above-mentioned structural configuration not only meets the requirements of rotor rotational stress, but also greatly reduces the leakage flux coefficient of the motor.

[0030] Preferably, a third magnetic isolation hole is provided on the inner side of the junction of the first magnetic pole and the second magnetic pole, and the third magnetic isolation hole is symmetrical with respect to the center line between the poles.

[0031] In this scheme, the above-mentioned structural configuration is used to reduce the self-coupling coefficient of the first magnetic pole and increase the amplitude of the air gap magnetic flux density of the motor, thereby improving the motor power and efficiency.

[0032] Preferably, the third magnetic isolation hole is a pentagonal magnetic isolation hole, with the tip of the pentagonal magnetic isolation hole facing the junction of the first magnetic isolation hole and the second magnetic isolation hole, and an I-shaped structure is formed between the first magnetic isolation hole, the second magnetic isolation hole, the third harmonic groove and the third magnetic isolation hole;

[0033] The central angle occupied by the pentagonal magnetic shielding hole in the circumferential direction of the unipolar rotor lamination The range of values ​​is ,

[0034] The distance between the midpoint of the bottom edge of the pentagonal magnetic shielding hole and the center of the unipolar rotor lamination The range of values ​​is ,in, Let be the radius of the first magnetic pole.

[0035] In this design, the first magnetic isolation hole, the second magnetic isolation hole, the third harmonic slot, and the third magnetic isolation hole together form an I-shaped structure. This I-shaped structure forms the transmission path for magnetic field lines, allowing them to be transmitted along the direction of the I-shaped structure, thus avoiding local magnetic saturation and preventing magnetic leakage. The pentagonal magnetic isolation hole is symmetrical about its tip relative to the center line between poles, with the tip pointing outwards to guide the magnetic field lines smoothly along both sides of the tip, preventing magnetic leakage.

[0036] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0037] The significant advantages of this invention are as follows: When permanent magnets are installed in each magnet slot of the rotor laminations, the rotor laminations are magnetized, forming alternating first and second magnetic poles along the circumference of the laminations. The area between adjacent second magnetic poles is then magnetized by the permanent magnets into a first magnetic pole with the opposite magnetic properties to the second magnetic pole. Although all permanent magnets have the same polarity, magnetizing the rotor laminations with permanent magnets still creates alternating N / S poles on the rotor laminations. Compared to alternating pole motors, this significantly reduces the number of permanent magnets required, improving economic efficiency. Setting the radius of the first magnetic pole larger than that of the second magnetic pole ensures the uniformity of the air gap magnetic flux per pole of the motor. It also reduces the amplitude of harmonic electromagnetic radial forces of various orders caused by the rotor magnetic field, thereby meeting the design requirements of different motors and reducing motor vibration and noise. A first harmonic slot is set on the first magnetic pole, and the distance between the bottom of the first harmonic slot and the center of the unipolar rotor lamination is set to be greater than or equal to 0.9 times the radius of the second magnetic pole. This can reduce the leakage flux coefficient of the motor, increase the main magnetic flux amplitude, improve motor efficiency, and optimize the direction of the magnetic field lines, thereby increasing torque. Setting multiple magnetic isolation holes can guide the direction of the magnetic field lines, avoid local magnetic saturation, and prevent leakage flux. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a unipolar rotor lamination of a motor according to a preferred embodiment of the present invention. Figure 1 .

[0039] Figure 2 This is a schematic diagram of the structure of a unipolar rotor lamination of a motor according to a preferred embodiment of the present invention. Figure 2 .

[0040] Figure 3 This is a comparison diagram showing the torque effect of an un-slotted optimized rotor lamination and a slotted optimized rotor lamination in a preferred embodiment of the present invention.

[0041] Figure 4 This is a comparison diagram of the circumferential distribution amplitude of electromagnetic radial force of an unslotted and slotted rotor lamination of a motor according to a preferred embodiment of the present invention.

[0042] Figure 5 The image shows an NVH simulation diagram of the unslotted optimized rotor laminations of a motor according to a preferred embodiment of the present invention.

[0043] Figure 6 The image shows the NVH simulation diagram of the slotted rotor lamination of a motor according to a preferred embodiment of the present invention.

[0044] Explanation of reference numerals in the attached figures:

[0045] Magnet trough 1

[0046] Permanent magnet segment 11

[0047] Magnetic shielding section 12

[0048] First magnetic pole 2

[0049] First harmonic slot 21

[0050] Second magnetic pole 3

[0051] Second harmonic slot 31

[0052] First magnetic shielding hole 4

[0053] Second magnetic shielding hole 5

[0054] Magnetic bridge 6

[0055] Third harmonic slot 7

[0056] Third magnetic isolation hole 8

[0057] 100 unipolar rotor laminations

[0058] Interpolar centerline 200 Detailed Implementation

[0059] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0060] like Figures 1-4 As shown, this embodiment discloses a unipolar motor based on the synergistic optimization of magnetic pole modulation and harmonic slots. It includes a unipolar rotor lamination 100, with at least two magnetic slots 1 on its end face (five slots are shown in the figure). These at least two magnetic slots 1 are spaced apart along the circumferential direction of the unipolar rotor lamination 100 to form alternating first magnetic poles 2 and second magnetic poles 3 on the outer circumferential surface of the unipolar rotor lamination 100. When a permanent magnet is installed in each magnetic slot 1 of the rotor lamination, its adjacent magnetic poles are magnetized, thus forming alternating first magnetic poles 2 and second magnetic poles 3 along the circumferential direction of the rotor lamination. The polarity of the first magnetic pole 2 is opposite to that of the second magnetic pole 3. Although all permanent magnets have the same polarity, by magnetizing the rotor lamination with permanent magnets, alternating N-S poles can still be formed on the rotor lamination. Compared with ordinary alternating pole motors, this significantly reduces the number of permanent magnets and improves economic efficiency. The outer circumferential arc of the first magnetic pole 2 and the outer circumferential arc of the second magnetic pole 3 are concentrically set with the center of the rotor lamination, and the radius R of the first magnetic pole 2 is set... pm The radius R of the second magnetic pole 3 is greater than that of the second magnetic pole 3. feCompared to existing technologies where unequal eccentric radii lead to a decrease in effective air gap flux and a reduction in average magnetic flux density, this design increases air gap reluctance while maintaining the effective area of ​​air gap flux without significant change, thus ensuring motor efficiency. Furthermore, it does not introduce additional harmonics. While ensuring the uniformity of air gap flux per pole of the motor, it reduces the amplitude of electromagnetic radial forces of various orders of harmonics caused by the rotor magnetic field, thereby reducing motor vibration and noise.

[0061] In this embodiment, the first magnetic pole 2 is a permanent magnet pole equipped with a permanent magnet, and the second magnetic pole 3 is a silicon steel pole. In another embodiment, when the silicon steel pole is the first magnetic pole 2, the permanent magnet pole is the second magnetic pole 3.

[0062] like Figure 1 As shown, in this embodiment, the first magnetic pole 2 has a first harmonic slot 21. The distance between the bottom of the first harmonic slot 21 and the center of the unipolar rotor lamination 100 is set to be greater than or equal to 0.9 times the radius of the second magnetic pole 3 and less than the radius of the unipolar rotor lamination. The radius of the unipolar rotor lamination is its nominal radius, which is also the theoretical design value of the radius of the unipolar rotor lamination, also called the initial value. In this embodiment, the nominal radius of the unipolar rotor lamination 100 is the radius of the virtual circle containing the outer circumference arc of the first magnetic pole 2. If the difference between the distance from the bottom of the first harmonic slot 21 to the center of the unipolar rotor lamination and the radius of the second magnetic pole 3 is too large, it will seriously affect the operating efficiency of the unipolar motor. By slotting the first magnetic pole 2 and optimizing the relationship between the first harmonic slot 21 and the radius of the second magnetic pole 3, the leakage flux coefficient of the motor can be reduced, the main magnetic flux amplitude of the motor can be increased, and the motor efficiency can be improved. Furthermore, the direction of the magnetic field lines can be optimized, increasing the torque.

[0063] Preferably, the bottom surface of the first harmonic slot 21 is an arc surface. The arc surface can disperse stress, avoid local stress peaks, reduce stress concentration during motor operation, and improve the mechanical fatigue life of the rotor.

[0064] like Figure 1As shown, in this embodiment, the second magnetic pole 3 has two second harmonic slots 31, which are spaced apart along the circumferential direction of the unipolar rotor lamination 100. The presence of the second harmonic slots 31 on the second magnetic pole 3 can suppress the harmonic amplitude generated at the position of the second magnetic pole 3. Preferably, setting the number of second harmonic slots 31 to two, with the two slots spaced apart along the circumferential direction of the unipolar rotor lamination 100, is equivalent to modulating the magnetic field twice, effectively suppressing spatial harmonics of a specific order, further reducing the amplitude of harmonics generated at the position of the second magnetic pole 3. This results in relatively smaller torque fluctuations, smoother motor operation, and ultimately, reduced noise. The two harmonic slots can also optimize the magnetic field lines on the second magnetic pole 3, reduce the motor leakage flux coefficient, increase the main magnetic flux amplitude, and improve motor efficiency.

[0065] Preferably, the number of second harmonic slots can be three or more.

[0066] like Figure 2 As shown, in this embodiment, the distance between the two second harmonic slots 31 along the circumferential direction of the unipolar rotor lamination 100 is the first distance, and the central angle corresponding to the first distance in the unipolar rotor lamination 100 is... The central angle corresponding to the first harmonic slot 21 in the unipolar rotor lamination 100 is equal. The slot opening of the first harmonic slot 21 is wider than that of the second harmonic slot 31. The larger slot opening can adjust the air gap magnetic field waveform, while the smaller slot opening can significantly reduce cogging torque. By associating the two second harmonic slots with the first harmonic slot 21, the three slots work together to precisely and efficiently reduce the amplitude of harmonics generated at the positions of the first magnetic pole 2 and the second magnetic pole 3, thereby reducing torque ripple and ultimately reducing motor vibration and noise.

[0067] The central angle corresponding to the first spacing in the unipolar rotor lamination 100 The range of values ​​is ,in, The central angle occupied by the first magnetic pole 2 in the unipolar rotor lamination 100 is given by [reference to angle]. The value is P represents the number of first magnetic poles 2. Each second harmonic slot 31 is a semi-circular slot, and the first spacing is the distance between the centers of two second harmonic slots. Preferably, the radius of the second harmonic slot 31... The range of values ​​is mm.

[0068] In this embodiment, the radius of the first magnetic pole 2 The radius of the second magnetic pole 3 The relationship is: Excessive radius difference will sacrifice average torque and reduce motor efficiency. Therefore, by optimizing... While ensuring motor performance, the amplitude of electromagnetic radial force caused by each order harmonic of the rotor magnetic field can be reduced, thereby reducing motor vibration and noise.

[0069] In this embodiment, the central angle corresponding to the first harmonic slot 21 along the circumferential direction of the unipolar rotor lamination 100 is... The range of values ​​is ,in, The central angle occupied by the first magnetic pole 2 in the unipolar rotor lamination 100 is given by [reference to angle]. The value is P represents the number of first magnetic poles 2. Too narrow a slot width cannot form a sufficiently large magnetic reluctance barrier, and some magnetic flux will pass through the iron core at the slot edge, forming a bypass and increasing the risk of magnetic leakage. Too wide a slot width will disrupt the continuity of the magnetic field, potentially exacerbating changes in air gap permeability and cogging torque. Optimizing a suitable harmonic slot can make the air gap magnetic field distribution more sinusoidal, reducing the amplitude of the electromagnetic radial force, decreasing motor vibration and noise, guiding the magnetic circuit direction, and reducing the rotor's secondary magnetic flux.

[0070] In another embodiment, when the silicon steel pole is the first magnetic pole 2 and the permanent magnet pole is the second magnetic pole 3, the first harmonic slot 21 is located on the silicon steel pole and the second harmonic slot 31 is located on the permanent magnet pole. This type of rotor can also reduce motor vibration and reduce vibration noise.

[0071] like Figure 1 and Figure 2 As shown, in this embodiment, the magnetic steel groove 1 includes a permanent magnet section 11 located in the middle and magnetic isolation sections 12 located at both ends of the magnetic steel groove 1. The two magnetic isolation sections 12 are symmetrical with respect to the permanent magnet section 11. The permanent magnet section 11 is used to install permanent magnets. After the permanent magnets are installed in the permanent magnet section 11, the magnetic isolation sections 12 extend along the axial direction of the unipolar rotor lamination 100 to form a first magnetic isolation hole 4. The magnetic isolation section 12 is used to optimize the direction of the magnetic lines of force at both ends of the permanent magnet and also to extend the conduction path of the magnetic lines of force, avoiding local magnetic saturation. The first magnetic isolation hole 4 can also be used to dissipate heat from the rotor lamination.

[0072] like Figure 1 and Figure 2As shown, in this embodiment, each second magnetic pole 3 has a second magnetic isolation hole 5 at both ends. The second magnetic isolation hole 5 is located close to the first magnetic isolation hole 4, and the second magnetic isolation hole 5 and the adjacent first magnetic isolation hole 4 form a magnetic isolation bridge 6. The magnetic isolation bridge 6 extends along the radial direction of the unipolar rotor lamination 100. There is an inter-pole center line 200 between the first magnetic pole 2 and the adjacent second magnetic pole 3. The first magnetic isolation hole 4 and the second magnetic isolation hole 5 are symmetrically arranged with respect to the inter-pole center line 200. The second magnetic isolation hole 5 is used to optimize the magnetic field line orientation at the position of the second magnetic pole 3 and also to dissipate heat from the rotor lamination. The magnetic isolation bridge 6 forms a magnetic field line conduction path, allowing the magnetic field lines to be conducted along the extension direction of the magnetic isolation bridge 6, preventing inter-pole magnetic leakage. The magnetic isolation bridge 6 can greatly reduce the leakage magnetic coefficient of the motor, while the strength of the magnetic isolation bridge 6 meets the rotational stress requirements of the rotor.

[0073] In this embodiment, the thickness of the magnetic isolation bridge 6 along the circumferential direction of the unipolar rotor lamination 100 is... The value range is 0.4mm < With a thickness of ≤0.5mm, it not only meets the requirements of rotor rotational stress but also greatly reduces the leakage flux coefficient of the motor.

[0074] Preferably, the distance between two adjacent second magnetic isolation holes 5 is equal to the length of the permanent magnet segment 11, so as to balance the magnetic force.

[0075] In this embodiment, a third harmonic slot 7 is provided on the outer peripheral surface of the unipolar rotor lamination 100, and the third harmonic slot 7 is also provided at the junction of the first magnetic pole 2 and the second magnetic pole 3. The third harmonic slot 7 is symmetrical with respect to the inter-pole center line 200. The aforementioned third harmonic slot 7 can optimize the pole arc coefficient of the rotor, thereby reducing the leakage flux coefficient and torque fluctuation of the motor.

[0076] like Figure 2 As shown, in this embodiment, the third harmonic slot 7 forms an isosceles trapezoidal slot structure with a larger outer diameter and a smaller inner diameter. The isosceles trapezoidal slot structure includes a short base and a long base. The central angle corresponding to the short base in the unipolar rotor lamination 100 is... The range of values ​​is The central angle corresponding to the long base in the unipolar rotor lamination 100 The range of values ​​is The above structural design is used to optimize the rotor's pole arc coefficient, thereby reducing the motor's leakage flux coefficient and torque ripple.

[0077] In this embodiment, the central angle occupied by the first magnetic isolation hole 4, the second magnetic isolation hole 5, and the magnetic isolation bridge 6 in the circumferential direction of the unipolar rotor lamination 100 is... The range of values ​​is The magnetic field lines at the junction of the first magnetic pole 2 and the second magnetic pole 3 are optimized to prevent local magnetic flux saturation and inter-pole magnetic leakage, thereby increasing the main magnetic flux amplitude of the motor and improving motor efficiency.

[0078] In this embodiment, a third magnetic isolation hole 8 is provided on the inner side of the junction of the first magnetic pole 2 and the second magnetic pole 3. The third magnetic isolation hole 8 is symmetrical with respect to the inter-pole center line 200. It is used to reduce the self-coupling coefficient of the second magnetic pole and increase the magnetic flux density amplitude of the motor air gap, thereby improving the motor power and efficiency.

[0079] In this embodiment, the third magnetic isolation hole 8 is a pentagonal magnetic isolation hole, with its tip facing the junction of the first magnetic isolation hole 4 and the second magnetic isolation hole 5. The first magnetic isolation hole 4, the second magnetic isolation hole 5, the third harmonic slot 7, and the third magnetic isolation hole 8 together form an I-shaped structure. The central angle occupied by the pentagonal magnetic isolation hole in the circumferential direction of the unipolar rotor lamination 100 is... The range of values ​​is The distance between the midpoint of the bottom edge of the pentagonal magnetic shielding hole and the center of the unipolar rotor lamination 100 The range of values ​​is ,in, The radius of the first magnetic pole 2 is given. The first magnetic isolation hole 4, the second magnetic isolation hole 5, the third harmonic slot 7, and the third magnetic isolation hole 8 together form an I-shaped structure. The I-shaped structure forms the transmission path of magnetic field lines, allowing the magnetic field lines to be transmitted along the direction of the I-shaped structure, avoiding local magnetic saturation and preventing magnetic leakage between poles. The pentagonal magnetic isolation holes are symmetrical about their tips relative to the center line 200 between poles, with the tips pointing outwards to guide the magnetic field lines to be transmitted smoothly along both sides of the tips, preventing magnetic leakage between poles. Preferably, the midpoint of the base of all the pentagonal magnetic isolation holes is within a radius of 200. On the circle.

[0080] In this embodiment, the unipolar rotor lamination 100 has a shaft hole in the middle for mounting a drive shaft.

[0081] The torques of the un-slotted and slotted optimized rotor laminations were simulated, and the simulation results are as follows: Figure 3 As shown, torque ripple decreased from 8% to 2%, and average torque increased from 3 Nm to 3.05 Nm. In this paper, the slotted and optimized rotor lamination is the rotor lamination of this application.

[0082] Furthermore, simulations were performed on the circumferential distribution amplitude of the electromagnetic radial force of the un-slotted and slotted rotor laminations. The simulation results are as follows: Figure 4As shown, the optimized magnetic radial force is significantly reduced, and the motor vibration and noise performance is improved. Furthermore, NVH (Noise, Vibration, Harshness) simulations of the rotor laminations are performed. The NVH simulation results for the un-slotted optimized rotor laminations are shown below. Figure 5 As shown, the NVH simulation results of the slotted optimized rotor laminations are as follows: Figure 6 As shown. From Figure 5 and Figure 6 The data shows that the highest sound pressure level before optimization was 78dB, and the highest sound pressure level after optimization was 33.4dB, indicating a significant improvement in the motor's noise and vibration performance.

[0083] This invention can be applied to the field of smart appliances to reduce operating noise, thereby protecting residents' hearing health and creating a better living environment. Taking a smart range hood equipped with the motor of this invention as an example, users can achieve intelligent motor control via voice commands. Because the motor of this invention has excellent performance and effectively reduces noise, it can improve the user experience and create a better, smarter kitchen. With its excellent noise reduction performance, the motor of this invention also has broad application prospects in fields such as new energy vehicles, aerospace, and CNC machine tools, effectively improving product comfort and high-end quality.

[0084] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A single polarity motor based on pole modulation and harmonic slot coordination optimization, characterized in that, It includes a single-pole rotor sheet, which has first and second magnetic poles arranged alternately in the circumferential direction, the polarities of the first and second magnetic poles being opposite, the outer periphery of the first magnetic pole having a first circular arc, the outer periphery of the second magnetic pole having a second circular arc, the first and second circular arcs being concentrically arranged with respect to the center of the single-pole rotor sheet, the radius of the first magnetic pole being greater than the radius of the second magnetic pole; The first magnetic pole is provided with a first harmonic slot, the distance from the bottom of the first harmonic slot to the center of the single-pole rotor sheet is greater than or equal to 0.9 times the radius of the second magnetic pole; the first magnetic pole is a permanent magnet pole provided with a permanent magnet, and the second magnetic pole is a silicon steel pole.

2. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 1, wherein, The second magnetic pole has a second harmonic slot, and the number of the second harmonic slot is two, and the two second harmonic slots are arranged at intervals along the circumferential direction of the single-pole rotor sheet.

3. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 2, wherein, The interval of the two second harmonic slots along the circumferential direction of the single-pole rotor sheet is a first interval, and the corresponding central angle of the first harmonic slot in the single-pole rotor sheet is equal to the corresponding central angle of the second harmonic slot in the single-pole rotor sheet.

4. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 1, wherein, a radius of the first magnetic pole a radius of the second magnetic pole .​ 5. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 1, wherein, The central angle corresponding to the width of the first harmonic slot along the circumferential direction of the unipolar rotor lamination The range of values ​​is ,in, The central angle occupied by the first magnetic pole in the unipolar rotor lamination is given by [reference to angle]. The value is P represents the number of the first magnetic poles.

6. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 1, wherein, The end surface of the single-pole rotor sheet has at least two magnetic steel grooves, and the at least two magnetic steel grooves are arranged at intervals along the circumferential direction of the single-pole rotor sheet, the magnetic steel grooves correspond to the first magnetic poles, the magnetic steel grooves include a permanent magnet segment in the middle and a magnetic shielding segment at both ends of the magnetic steel groove, the two magnetic shielding segments are symmetrical with respect to the permanent magnet segment, the permanent magnet segment is used to install a permanent magnet, and the magnetic shielding segment extends along the axial direction of the single-pole rotor sheet to form a first magnetic shielding hole.

7. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 6, wherein, Each of the second magnetic poles is provided with a second magnetic shielding hole at both ends, respectively, the second magnetic shielding hole is arranged close to the first magnetic shielding hole, the second magnetic shielding hole and the adjacent first magnetic shielding hole form a magnetic shielding bridge, the magnetic shielding bridge extends along the radial direction of the single-pole rotor sheet, the first magnetic pole and the adjacent second magnetic pole have an inter-pole center line, and the first magnetic shielding hole and the second magnetic shielding hole are symmetrically arranged with respect to the inter-pole center line.

8. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 7, wherein, The outer circumferential surface of the single-pole rotor sheet is provided with a third harmonic slot, the combination part of the first magnetic pole and the second magnetic pole is provided with the third harmonic slot, and the third harmonic slot is symmetrical with respect to the inter-pole center line.

9. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 8, wherein, The third harmonic slot forms an isosceles trapezoidal slot structure with an outer large and inner small, the isosceles trapezoidal slot structure includes a short bottom and a long bottom, the short bottom corresponds to a central angle of the single-pole rotor lamination The value range of The long bottom corresponds to a central angle of the single-pole rotor lamination The value range of , wherein The central angle of the first magnetic pole in the single-pole rotor lamination, The value of P is the number of first magnetic poles.

10. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 9, wherein, The first magnetic isolation hole, the second magnetic isolation hole and the magnetic isolation bridge occupy a central angle in the circumferential direction of the single-polarity rotor lamination The value range of the central angle is .

11. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 7, wherein, a thickness of the magnetic isolation bridge in a circumferential direction of the unipolar rotor lamination is in the range of 0.4 mm < d < 0.5 mm. is in the range of 0.4 mm < d < 0.5 mm.

12. The single polarity machine based on pole modulation and harmonic slot coordination optimization of claim 10, wherein, The inner side of the combination part of the first magnetic pole and the second magnetic pole is provided with a third magnetic shielding hole, and the third magnetic shielding hole is symmetrical with respect to the inter-pole center line.

13. The single polarity machine based on pole modulation and harmonic slot cooperation optimization of claim 12, wherein, The third magnetic shielding hole is a pentagonal magnetic shielding hole, the tip of the pentagonal magnetic shielding hole faces the combination part of the first magnetic shielding hole and the second magnetic shielding hole, and a I-shaped structure is formed between the first magnetic shielding hole, the second magnetic shielding hole, the third harmonic slot and the third magnetic shielding hole, The central angle of the five-edge magnetic isolation hole in the circumferential direction of the single-polarity rotor lamination The value range of the central angle of the five-edge magnetic isolation hole in the circumferential direction of the single-polarity rotor lamination is The value range of the central angle of the five-edge magnetic isolation hole in the circumferential direction of the single-polarity rotor lamination is the distance between the midpoint of the bottom side of the five-sided magnetic isolation hole and the center of the single-polarity rotor lamination the value range of the radius of the first magnetic pole is wherein, the radius of the first magnetic pole.

Images