Motor, compressor, and vehicle

By using cerium to replace praseodymium and neodymium in the permanent magnet of the motor, the material usage is optimized, and the problems of high cost and insufficient performance are solved, and the cost-effectiveness and high-speed load capacity are enhanced.

WO2025001666A1PCT designated stage expired Publication Date: 2025-01-02ANHUI WELLING AUTO PARTS CO LTD +2

Patent Information

Application Number
PCT/CN2024/095091
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-06-30
Filing Date
2024-05-24
Publication Date
2025-01-02

AI Technical Summary

Technical Problem

The high cost of rare earth elements such as praseodymium and neodymium in existing motors leads to high motor costs, and the high content of praseodymium and neodymium in permanent magnets will reduce the magnetic energy production and affect the performance of the motor.

Method used

By introducing cerium into the permanent magnet, the content of praseodymium neodymium is reduced, and by optimizing the material usage of the permanent magnet and winding, the mass percentage and weight of cerium are adjusted to meet the specific backpotential value and maximum allowable operating voltage conditions, ensuring The load capacity and cost-effectiveness of the motor when it is weak at high speed.

Benefits of technology

It effectively reduces the production cost of the motor, improves the cost performance, and enhances the load capacity of the motor under high-speed weak magnetic conditions, reducing the impact of armature reaction.

✦ Generated by Eureka AI based on patent content.

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Abstract

The present application provides a motor, a compressor, and a vehicle. The motor comprises: a rotor, wherein the rotor comprises a rotor core and a plurality of permanent magnets, the rotor core is provided with a plurality of magnet slot groups, the plurality of magnet slot groups are arranged at intervals around the axis of the rotor core, one permanent magnet is provided in each magnet slot group, and each permanent magnet contains cerium with a mass percentage of X%; and a stator, wherein the stator comprises a stator core and a winding, the stator core comprises a plurality of stator teeth, the plurality of stator teeth are arranged at intervals around the axis of the stator core, the plurality of stator teeth define a mounting cavity, the rotor is rotatably provided in the mounting cavity, and the winding is wound on the plurality of stator teeth. The weight of the plurality of permanent magnets is denoted as Mp, the weight of the winding is denoted as Mc, the back electromotive force value of the motor at the rotation speed of 1000 rpm is denoted as Ke, and the highest allowable working voltage of a power device of a controller of the motor is denoted as Ub, wherein (Mp / Mc)xUbxX%≤Ke. In the present application, the structure of the motor is reasonably arranged, so that the influence of the armature reaction when the motor is loaded is reduced while the cost performance of the motor is improved, facilitating enhancement of the load capacity of the motor during high-speed flux weakening.
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Description

Motors, compressors and vehicles

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on June 30, 2023, with application number "202310791397.X" and invention name "Motor, Compressor and Vehicle", the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of motors, and in particular to a motor, a compressor and a vehicle. Background Art

[0003] In the related art, the permanent magnets of the motor are neodymium iron boron permanent magnets, which contain a large amount of precious rare earth elements such as praseodymium and neodymium, thus resulting in a high cost of the motor. Technical Solutions

[0004] This application aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] To this end, a first aspect of the present application provides a motor.

[0006] A second aspect of the present application provides a compressor.

[0007] A third aspect of the present application provides a vehicle.

[0008] In view of this, the first aspect of the present application proposes a motor, comprising: a rotor, the rotor comprising a rotor core and a plurality of permanent magnets, the rotor core being provided with a plurality of magnet slot groups, the plurality of magnet slot groups being arranged at intervals around the axis of the rotor core, a permanent magnet being arranged in each magnet slot group, the permanent magnet containing X% by mass of cerium; a stator, the stator comprising a stator core and a winding, the stator core comprising a plurality of stator teeth, the plurality of stator teeth being arranged at intervals around the axis of the stator core, the plurality of stator teeth enclosing a mounting cavity, the rotor being rotatably disposed in the mounting cavity, and the winding being wound on the plurality of stator teeth; the weight of the plurality of permanent magnets being denoted as Mp, the weight of the winding being denoted as Mc, the back electromotive force value of the motor at a speed of 1000 rpm being denoted as Ke, and the maximum allowable operating voltage of the power device of the controller of the motor being denoted as Ub, wherein (Mp / Mc)×Ub×X%≤Ke.

[0009] The motor described above in this application may also have the following additional technical features:

[0010] In the above technical solution, further, Mp, Mc, Ub and X% satisfy: 0.14×Ke≤(Mp / Mc)×Ub×X%≤0.69×Ke.

[0011] In any of the above technical solutions, further, the weight of the rotor core is recorded as Mr, wherein 0.17≤Mp / Mr≤0.26.

[0012] In any of the above technical solutions, further, the rotor core is further provided with a plurality of slit groups, a slit group is arranged between each magnet slot group and the outer peripheral wall of the rotor core, and the slit group includes an odd number of slits.

[0013] In any of the above technical solutions, further, the rotor core has multiple magnetic pole center lines, each slot group is located at a magnetic pole center line, a part of the slots in the slot group are located on the first side of the magnetic pole center line, and another part of the slots in the slot group are located on the second side of the magnetic pole center line.

[0014] In any of the above technical solutions, further, the slit group includes two first slits, the two first slits are symmetrically arranged with the magnetic pole center line as the symmetry axis, the first slit includes a first end and a second end, the first ends of the two first slits are adjacent to each other, the second ends of the two first slits are far away from each other, the second end is located between the first end and the magnet slot group, and the angle formed between the two first slits is recorded as α; the magnet slot group includes two slot bodies, the slot body includes a third end and a fourth end, the third ends of the two slot bodies are far away from each other, the fourth ends of the two slot bodies are adjacent to each other, and the fourth end is located between the third end and the axis of the rotor core; the angle formed between the first slit and the slot body located on the same side of the magnetic pole center line is recorded as β; the stator tooth includes a tooth body and a tooth shoe, the tooth shoe is connected to the circumferential end face of the tooth body, and the circumferential width of the tooth body is recorded as Bt; the circumferential width of the permanent magnet is recorded as H; wherein H<α / β×Bt≤3.4mm, 1.5mm≤H≤2mm.

[0015] In any of the above technical solutions, further, the slit group further includes a second slit, the second slit is located on a first side of the magnetic pole center line, and the second slit is parallel to the first slit.

[0016] In any of the above technical solutions, further, the two first slits are arranged adjacent to the magnetic pole center line, and the second slit is located on a side of the first slit away from the magnetic pole center line.

[0017] In any of the above technical solutions, further, the rotor rotates in a direction from the second side of the magnetic pole center line to the first side of the magnetic pole center line.

[0018] In any of the above technical solutions, further, the mass percentage of cerium in the permanent magnet satisfies: 2%<X%<6%.

[0019] In any of the above technical solutions, further, the maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

[0020] In any of the above technical solutions, further, the residual magnetic flux density Br of the permanent magnet at 20° C. satisfies: 1.2T≤Br≤1.5T.

[0021] In any of the above technical solutions, further, the intrinsic coercive force Hcj of the permanent magnet at 20° C. satisfies: 21.3 kOe≤Hcj≤25.2 kOe.

[0022] A second aspect of the present application provides a compressor, comprising: a motor as in any technical solution of the first aspect.

[0023] A third aspect of the present application provides a vehicle, comprising: the compressor as in the second aspect.

[0024] Additional aspects and advantages of the present application will become apparent in the following description or may be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0026] FIG1 is a schematic diagram showing a partial structure of a motor according to an embodiment of the present application;

[0027] FIG2 is a schematic diagram showing a partial structure of a rotor according to an embodiment of the present application;

[0028] FIG3 shows a maximum torque variation curve of a motor according to an embodiment of the present application;

[0029] FIG4 is a schematic diagram showing a comparison of the cogging torque of the motors in the present application and related art;

[0030] FIG5 shows a torque ripple variation curve diagram of a motor according to an embodiment of the present application;

[0031] FIG6 shows a curve diagram of flux linkage variation of the stator and rotor of a motor according to an embodiment of the present application.

[0032] The corresponding relationship between the reference numerals and component names in FIG1 and FIG2 is as follows:

[0033] 10 motor, 100 rotor, 110 rotor core, 120 permanent magnet, 130 magnet slot group, 132 slot body, 1322 third end, 1324 fourth end, 140 slot group, 142 slot, 144 first slot, 1442 first end, 1444 second end, 146 second slot, 150 magnetic pole centerline, 200 stator, 210 stator core, 212 stator teeth, 2122 tooth body, 2124 tooth shoe, 214 mounting cavity, 220 winding. Modes for Carrying Out the Invention

[0034] In order to more clearly understand the above-mentioned objects, features and advantages of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other in the absence of conflict.

[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0036] 1 to 6 , a motor 10 , a compressor, and a vehicle according to some embodiments of the present application are described below.

[0037] As shown in FIG. 1 and FIG. 2 , a motor 10 according to some embodiments of the present application includes a rotor 100 and a stator 200 .

[0038] The rotor 100 includes a rotor core 110 and a plurality of permanent magnets 120 .

[0039] The rotor core 110 is provided with a plurality of magnet slot groups 130 , and the plurality of magnet slot groups 130 are arranged at intervals around the axis of the rotor core 110 .

[0040] A permanent magnet 120 is disposed in each magnet slot group 130 .

[0041] The permanent magnet 120 contains X mass % of cerium.

[0042] The stator 200 includes a stator core 210 and a winding 220 .

[0043] The stator core 210 includes a plurality of stator teeth 212 , which are spaced apart around the axis of the stator core 210 .

[0044] The plurality of stator teeth 212 enclose a mounting cavity 214 , and the rotor 100 is rotatably disposed in the mounting cavity 214 .

[0045] The winding 220 is wound around the plurality of stator teeth 212 .

[0046] The weight of the plurality of permanent magnets 120 is denoted as Mp.

[0047] The weight of the winding 220 is denoted as Mc.

[0048] The back electromotive force value of the motor 10 at a rotation speed of 1000 rpm is recorded as Ke.

[0049] The maximum allowable operating voltage of the power devices of the controller of the motor 10 is denoted as Ub.

[0050] Among them, (Mp / Mc)×Ub×X%≤Ke.

[0051] In this embodiment, the motor 10 includes a rotor 100 and a stator 200 .

[0052] The rotor 100 includes a rotor core 110 and a plurality of permanent magnets 120 . The rotor core 110 is provided with a plurality of magnet slot groups 130 . Each magnet slot group 130 is provided with a permanent magnet 120 . The permanent magnet 120 contains X% cerium by mass.

[0053] The stator 200 includes a stator core 210 and a winding 220 . The stator core 210 includes a plurality of stator teeth 212 . The winding 220 is wound around the plurality of stator teeth 212 .

[0054] The weight of the plurality of permanent magnets 120 is recorded as Mp, the weight of the winding 220 is recorded as Mc, the back electromotive force value of the motor 10 at a speed of 1000 rpm is recorded as Ke, and the maximum allowable operating voltage of the power device of the controller of the motor 10 is recorded as Ub.

[0055] Among them, using the permanent magnet 120 containing cerium as the magnetic pole can reduce the content of praseodymium and neodymium elements in the permanent magnet 120. In this way, the production cost of the permanent magnet 120 can be reduced, and then the production cost of the motor 10 can be reduced, solving the problem in the related art that the cost of the motor 10 is high due to the high price of rare earth materials such as praseodymium and neodymium.

[0056] By replacing the relatively expensive praseodymium and neodymium elements in the permanent magnet 120 with the abundant and relatively cheap cerium element, the price of the permanent magnet 120 can be effectively reduced, thereby improving the cost-effectiveness of the motor 10. However, the introduction of the cerium element will reduce the coercive force of the permanent magnet 120 to a certain extent, thereby reducing the magnetic energy product of the permanent magnet 120, and weakening the magnetic properties of the rotor 100. In order to ensure that the air gap composite magnetic field remains unchanged, the magnetic field strength of the stator 200 is usually increased by increasing the amount of windings 220 of the stator 200. At the same time, the operation of the motor 10 is usually regulated by a controller, and once the model of the power device in the controller is determined, the maximum operating voltage of the power device is determined accordingly. Since the rotor 100 magnetic field provided by the permanent magnet 120 of the motor 10 is not adjustable, in order to prevent the load voltage of the motor 10 from exceeding the allowable value of the power device at high speed, weak magnetic control is usually required. Simply increasing the magnetic field strength of stator 200 to compensate for the loss of the air gap composite magnetic field will exacerbate the armature reaction of stator 200, hindering the output capacity of motor 10 during high-speed field weakening, thereby limiting the operating range of the compressor. This requires a matching and balanced design of the stator and rotor magnetic fields of motor 10, and reasonable adjustment of the material usage of motor 10's permanent magnets 120, windings 220, and other materials. Within the constraints of the maximum operating voltage of the power devices, the design value of motor 10's back EMF meets the motor 10's field weakening overload capacity, thereby improving the cost-effectiveness of motor 10.

[0057] It can be understood that when the load is symmetrical, the effect of the armature magnetomotive force on the fundamental wave of the main pole magnetic field is the armature reaction. The armature reaction will affect the performance of the motor 10. The influence of the armature reaction can be reduced from two aspects. First, the magnetic field of the stator 200 is weakened. Second, the magnetic field of the rotor 100 is enhanced. The magnetic field of the stator 200 is correlated with the parameters of the winding 220 wound on the stator teeth 212 of the stator core 210. The magnetic field of the rotor 100 is correlated with the parameters of the permanent magnet 120. Therefore, by optimizing the relationship between the weight Mp of multiple permanent magnets 120 and the weight Mc of the winding 220, the air gap synthetic magnetic field can be in a balanced state. In this way, the output capacity of the motor 10 at high speed and weak magnetic field can be improved, which is conducive to reducing the armature reaction.

[0058] It is understood that permanent magnets 120 contain cerium, and the amount of cerium used can also affect the magnetic field of rotor 100. If the mass percentage of cerium in permanent magnets 120 is too high, it will not be conducive to improving the magnetic field of rotor 100 and may aggravate armature reaction. If the mass percentage of cerium in permanent magnets 120 is too low, the production cost of rotor 100 will still be high.

[0059] It is understood that the back EMF value Ke of the motor 10 at 1000 rpm is correlated with the maximum allowable operating voltage Ub of the power devices of the controller of the motor 10. If the back EMF value Ke of the motor 10 at 1000 rpm is too high, the power devices may be easily broken down. If the back EMF value Ke of the motor 10 at 1000 rpm is too low, the performance of the motor 10 may not be effectively utilized.

[0060] Therefore, by rationally setting the relationship between the mass percentage X% of cerium in each permanent magnet 120, the weight Mp of the multiple permanent magnets 120, the weight Mc of the winding 220, the maximum allowable operating voltage Ub of the power components of the motor 10 controller, and the back EMF value Ke of the motor 10 at 1000 rpm, so that the following is satisfied: (Mp / Mc) × Ub × X% ≤ Ke, the cost-effectiveness of the motor 10 can be improved while reducing the impact of the armature reaction under load. This helps enhance the load capacity of the motor 10 under high-speed field-weakening conditions and reduces the production cost of the motor 10. Consequently, by using permanent magnets 120 with a higher cerium content, the praseodymium and neodymium content in the permanent magnets 120 can be reduced, achieving even greater cost reduction and efficiency improvement.

[0061] In some embodiments, the unit of the weight Mp of the permanent magnet 120 is g, the unit of the weight Mc of the winding 220 is g, the unit of the maximum allowable operating voltage Ub of the power device of the controller of the motor 10 is V, and the unit of the back electromotive force value Ke of the motor 10 at a speed of 1000 rpm is V / krpm.

[0062] In some embodiments, Mp, Mc, Ub, and X% satisfy: 0.14×Ke≤(Mp / Mc)×Ub×X%≤0.69×Ke.

[0063] In this embodiment, the relationship between the mass percentage (X%) of cerium in each permanent magnet 120, the weight (Mp) of the permanent magnets 120, the weight (Mc) of the windings 220, the maximum allowable operating voltage (Ub) of the power components of the motor 10 controller, and the back EMF (Ke) of the motor 10 at 1000 rpm is further defined to satisfy the following: 0.14 × Ke ≤ (Mp / Mc) × Ub × X% ≤ 0.69 × Ke. This improves the cost-effectiveness of the motor 10 while reducing the impact of armature reaction under load and enhancing the motor's load capacity during high-speed field-weakening.

[0064] The armature reaction can be measured by the maximum torque of the motor 10. FIG3 shows a maximum torque curve of the motor 10. As can be seen from FIG3, when the above relationship between Mp, Mc, Ub and X% is between 0.14×Ke and 0.69×Ke, the maximum torque of the motor 10 is higher, which can reduce the influence of the armature reaction when the motor 10 is loaded.

[0065] In some embodiments, (Mp / Mc)×Ub×X%=0.2×Ke, (Mp / Mc)×Ub×X%=0.25×Ke, (Mp / Mc)×Ub×X%=0.3×Ke, (Mp / Mc)×Ub×X%=0.34×Ke, (Mp / Mc)×Ub×X%=0.4×Ke, (Mp / Mc)×Ub×X%=0.46×Ke, (Mp / Mc)×Ub×X%=0.5×Ke, (Mp / Mc)×Ub×X%=0.57×Ke and (Mp / Mc)×Ub×X%=0.6×Ke, etc., which are not listed here one by one.

[0066] In some embodiments, the weight of the rotor core 110 is denoted as Mr, where 0.17≤Mp / Mr≤0.26.

[0067] In this embodiment, the matching structure of the rotor core 110 and the permanent magnets 120 is further defined such that the weight of the rotor core 110, Mr, and the weight of the plurality of permanent magnets 120, Mp, satisfy the following relationship: 0.17 ≤ Mp / Mr ≤ 0.26. This ensures that the permanent magnet field strength of the rotor 100 is within a reasonable range, thereby improving the torque output capability of the motor 10.

[0068] Figure 6 is a graph of the rotor flux and the stator armature flux of motor 10 at maximum load. The difference between the rotor flux and the stator armature flux can quantitatively describe the degree of loaded armature reaction of motor 10. A strong armature magnetic field will lead to a deeper field weakening depth at high speeds of motor 10, resulting in a sharp drop in torque output. A strong permanent magnet field of rotor 100 will limit the high-speed operation of motor 10. Therefore, by reasonably limiting the relationship between the weight Mr of rotor core 110 and the weight Mp of the plurality of permanent magnets 120, the absolute value of the difference between the rotor flux and the stator armature flux does not exceed 20%. The magnetic fields of stator 200 and rotor 100 of motor 10 are in a relatively balanced state, which is beneficial to field weakening at high speeds of motor 10 and can improve the high-speed field weakening output capability of motor 10.

[0069] In some embodiments, the ratio of the weight Mp of the plurality of permanent magnets 120 to the weight Mr of the rotor core 110 includes: 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, etc., which are not listed here one by one.

[0070] In some embodiments, as shown in FIG. 1 and FIG. 2 , the rotor core 110 is further provided with a plurality of slot groups 140 .

[0071] A slot group 140 is disposed between each magnet slot group 130 and the outer peripheral wall of the rotor core 110 . The slot group 140 includes an odd number of slots 142 .

[0072] In this embodiment, the structure of the rotor core 110 is further defined such that the rotor core 110 is further provided with a plurality of slot groups 140, which are spaced apart around the axis of the rotor core 110. A slot group 140 is disposed between each magnet slot group 130 and the outer peripheral wall of the rotor core 110.

[0073] The slit group 140 includes an odd number of slits 142 .

[0074] The motor 10 is applied to a compressor. Since the compressor is a pulsating load, the structure of the rotor 100 is reasonably set so that the slot group 140 on the rotor core 110 includes an odd number of slots 142 .

[0075] In this way, the radial force density of the motor 10 can be effectively improved, the noise and vibration level of the motor 10 can be improved, and the noise and vibration of the compressor can be improved.

[0076] In some embodiments, as shown in FIG. 1 and FIG. 2 , the rotor core 110 has a plurality of magnetic pole center lines 150 , and each slot group 140 is located at one magnetic pole center line 150 .

[0077] A portion of the slots 142 of the slot group 140 is located on a first side of the magnetic pole centerline 150 .

[0078] Another portion of the slots 142 of the slot group 140 is located on a second side of the magnetic pole centerline 150 .

[0079] In this embodiment, the structure of the rotor core 110 is further refined so that the rotor core 110 has multiple magnetic pole center lines 150. For example, the line connecting the center of the magnet slot group 130 and the center of the axial hole of the rotor core 110 constitutes the magnetic pole center line 150, and the magnetic pole center line 150 is referred to as the d-axis.

[0080] By properly arranging the matching structure between the odd-numbered slits 142 of the slit group 140 and the magnetic pole centerline 150, a portion of the slits 142 of the slit group 140 is located on a first side of the magnetic pole centerline 150, while another portion of the slits 142 of the slit group 140 is located on a second side of the magnetic pole centerline 150. In other words, the arrangement positions of the odd-numbered slits 142 of the slit group 140 relative to the magnetic pole centerline 150 are divided. Since each slit group 140 has an odd number of slits 142, and the odd-numbered slits 142 are distributed on opposite sides of the magnetic pole centerline 150 (i.e., on the first side of the magnetic pole centerline 150 and on the second side of the magnetic pole centerline 150), an even number of slits 142 are arranged on the first side of the magnetic pole centerline 150, and an odd number of slits 142 are arranged on the second side of the magnetic pole centerline 150. Alternatively, an odd number of slits 142 are arranged on the first side of the magnetic pole centerline 150, and an even number of slits 142 are arranged on the second side of the magnetic pole centerline 150. In other words, the odd-numbered slits 142 of the slit group 140 are asymmetrically arranged along the magnetic pole centerline 150.

[0081] Exemplarily, the number of slot groups 140 is an even number, and the number of magnet slot groups 130 is an even number. The number of slot groups 140 matches the number of magnet slot groups 130, with each magnet slot group 130 corresponding to a slot group 140. The line containing the magnetic pole centerline 150 corresponds to two slot groups 140, which are referred to as the first slot group and the second slot group, respectively. The axis of the rotor core 110 is located between the first slot group and the second slot group. After the first slot group rotates 180° in the direction of rotation of the rotor 100, the slots 142 of the first slot group overlap with the slots 142 of the second slot group. Similarly, after the second slot group rotates 180° in the direction of rotation of the rotor 100, the slots 142 of the second slot group overlap with the slots 142 of the first slot group.

[0082] The arrows in FIG. 2 indicate the rotation direction of the rotor 100 .

[0083] This arrangement prevents the center of mass of the rotor 100 from deviating from the axis of rotation during rotation, thus maintaining the dynamic balance of the motor 10. Local wear and tear will not be aggravated. Taking a 12-slot 8-pole motor as an example, the odd-numbered slits 142 of the slit group 140 are asymmetrically arranged along the magnetic pole centerline 150. The radial force density at the 4th-order 16th-order mechanical frequency is reduced by 53%, and the noise level of the compressor in this frequency band is reduced by 5dB, with a significant noise improvement effect.

[0084] In some embodiments, the slit group 140 includes two first slits 144 .

[0085] The two first slits 144 are symmetrically arranged with the magnetic pole center line 150 as a symmetry axis.

[0086] The first slit 144 includes a first end 1442 and a second end 1444 .

[0087] The first ends 1442 of the two first slits 144 are adjacent to each other, and the second ends 1444 of the two first slits 144 are far away from each other.

[0088] The second end portion 1444 is located between the first end portion 1442 and the magnet slot set 130 .

[0089] The angle formed between the two first slits 144 is denoted as α.

[0090] The magnet slot set 130 includes two slot bodies 132 .

[0091] The slot body 132 includes a third end 1322 and a fourth end 1324 .

[0092] The third ends 1322 of the two slot bodies 132 are far away from each other, and the fourth ends 1324 of the two slot bodies 132 are closely adjacent to each other.

[0093] The fourth end portion 1324 is located between the third end portion 1322 and the axis of the rotor core 110 .

[0094] The angle formed between the first slit 144 and the slot body 132 on the same side of the magnetic pole centerline 150 is denoted as β.

[0095] The stator tooth 212 includes a tooth body 2122 and a tooth shoe 2124 .

[0096] The tooth shoe 2124 is connected to the circumferential end surface of the tooth body 2122 .

[0097] The circumferential width of the tooth body 2122 is denoted as Bt.

[0098] The circumferential width of the permanent magnet 120 is denoted by H.

[0099] Among them, H<α / β×Bt≤3.4mm, 1.5mm≤H≤2mm.

[0100] In this embodiment, the structure of the rotor core 110 is further defined.

[0101] In some embodiments, the slit group 140 includes two first slits 144, which are symmetrically arranged with the magnetic pole centerline 150 as the axis of symmetry. Each first slit 144 includes a first end 1442 and a second end 1444. The first ends 1442 of the two first slits 144 are adjacent to each other, and the second ends 1444 of the two first slits 144 are separated from each other. The second ends 1444 are located between the first ends 1442 and the magnet slot group 130. In other words, the two first slits 144 are configured in an "eight" shape. The angle formed between the two first slits 144 is denoted as α, and the angle α is an acute angle.

[0102] In some embodiments, the magnet slot group 130 includes two slot bodies 132, each slot body 132 including a third end 1322 and a fourth end 1324. The third ends 1322 of the two slot bodies 132 are far away from each other, and the fourth ends 1324 of the two slot bodies 132 are adjacent to each other, and the fourth end 1324 is located between the third end 1322 and the axis of the rotor core 110. That is, the two slot bodies 132 are configured in a "V" shape. The angle formed between the first slit 144 and the slot body 132 on the same side of the magnetic pole centerline 150 is denoted as β, and the angle β is an acute angle. As shown in FIG2 , the circumferential end surface of the first slit 144 facing the magnetic pole centerline 150 is the first side surface, and the radial end surface of the slot body 132 facing the first slit 144 is the second side surface. The angle formed between the first side surface and the second side surface is denoted as β.

[0103] As shown in FIG1 , the stator tooth 212 includes a tooth body 2122 and a tooth shoe 2124. The tooth body 2122 extends radially along the rotor core 110. The tooth shoe 2124 is connected to the tooth body 2122 and is located at the circumferential end surface of the tooth body 2122. Along the circumference of the rotor core 110, the tooth body 2122 has a width Bt.

[0104] As shown in FIG. 2 , the width of the permanent magnet 120 along the circumferential direction of the rotor core 110 is denoted as H.

[0105] By properly setting the angle α formed between the two first slits 144, the angle β formed between the first slit 144 and the slot body 132 on the same side of the magnetic pole centerline 150, the circumferential width H of the permanent magnet 120, and the circumferential width Bt of the tooth body 2122, the relationship satisfies: H < α / β × Bt ≤ 3.4 mm, and 1.5 mm ≤ H ≤ 2 mm. This setting can reduce the no-load cogging torque of the motor 10 and reduce load torque pulsation. At the same time, this setting ensures that the magnetic field at the stator core 210 does not oversaturate, which is beneficial to improving the output capacity of the motor 10.

[0106] FIG4 is a graph comparing the cogging torque values ​​of a motor of the related art (the motor is not provided with the slit group of the present application) and the motor 10 of the present application. Specifically, taking α=34°, β=107.5°, Bt=8.1mm, and H=2mm as an example, when the motor 10 includes multiple slit groups 140, and the odd number of slits 142 in each slit group 140 is asymmetrically arranged along the magnetic pole centerline 150, the no-load cogging torque is 0.21Nm, while the no-load cogging torque of the motor of the related art is 0.98Nm. It can be seen that the cogging torque of the motor 10 according to the present application is only 21.4% of the cogging torque of the motor of the related art, and the cogging torque reduction effect is obvious.

[0107] In some embodiments, as shown in FIG. 1 and FIG. 2 , the slit group 140 further includes a second slit 146 .

[0108] The second slit 146 is located on a first side of the magnetic pole centerline 150 , and the second slit 146 is parallel to the first slit 144 .

[0109] In this embodiment, the slit group 140 includes two first slits 144 and a second slit 146. One of the first slits 144 and the second slit 146 is located on a first side of the magnetic pole centerline 150, and the first slit 144 and the second slit 146 located on the first side of the magnetic pole centerline 150 are arranged in parallel. The other first slit 144 is located on a second side of the magnetic pole centerline 150. The two first slits 144 are symmetrically arranged with the magnetic pole centerline 150 as the axis of symmetry.

[0110] That is to say, the number of slits 142 located on the first side of the magnetic pole center line 150 is greater than the number of slits 142 located on the second side of the magnetic pole center line 150. This setting can ensure that the waveform of the air gap magnetic density of the motor 10 under load conditions is close to a sine wave, thereby reducing the torque pulsation during the operation of the motor 10. Improve the vibration noise during the operation of the motor 10. At the same time, this setting can ensure the dynamic balance of the rotor 100 during the rotation process, reduce the swing of the shaft structure of the compressor, and can effectively improve the content of each harmonic of the air gap magnetic density of the motor 10. In this way, on the one hand, the iron loss of the stator 200 of the motor 10 is reduced, which is conducive to improving the operating efficiency of the motor 10. On the other hand, it can improve the vibration noise of the motor 10, thereby reducing the operating noise of the compressor.

[0111] In some embodiments, as shown in FIG. 1 and FIG. 2 , the two first slits 144 are disposed adjacent to the magnetic pole centerline 150 .

[0112] The second slit 146 is located on a side of the first slit 144 away from the magnetic pole centerline 150 .

[0113] In this embodiment, the matching structure of the two first slits 144 and the second slit 146 is further defined, such that the two first slits 144 are located adjacent to the magnetic pole centerline 150, and the second slit 146 is located on the side of the first slit 144 away from the magnetic pole centerline 150. In other words, the second slit 146 is located outside the first slit 144. In other words, the first slit 144 is closer to the magnetic pole centerline 150 than the second slit 146.

[0114] The compressor load is not constant but rather fluctuates periodically. Positioning second slit 146 outside first slit 144 facilitates ensuring a sinusoidal waveform of the air gap flux density of motor 10 under load conditions, thereby reducing torque ripple and improving vibration and noise during operation. Furthermore, the asymmetric structure ensures the dynamic balance of rotor 100 during rotation, reduces vibration of the compressor shaft structure, and effectively improves the harmonic content of the air gap flux density of motor 10.

[0115] In some embodiments, as shown in FIG. 2 , the rotor 100 rotates in a direction from the second side of the magnetic pole centerline 150 to the first side of the magnetic pole centerline 150 .

[0116] In this embodiment, the relationship between the rotation direction of the rotor and the first side and the second side of the magnetic pole centerline 150 is further defined.

[0117] In some embodiments, the rotor 100 rotates from the second side of the magnetic pole centerline 150 to the first side of the magnetic pole centerline 150. It can also be understood that the first side of the magnetic pole centerline 150 is the windward side, and the second side of the magnetic pole centerline 150 is the leeward side.

[0118] That is, one first slit 144 and one second slit 146 are located on the windward side of the magnetic pole centerline 150, and the other first slit 144 is located on the leeward side of the magnetic pole centerline 150. In other words, one first slit 144 and one second slit 146 are arranged at the magnetic pole portion position in the same direction as the rotation direction of the rotor 100.

[0119] This arrangement is beneficial for reducing the no-load cogging torque and load electromagnetic torque pulsation of the motor 10 .

[0120] In some embodiments, the mass percentage of cerium in the permanent magnet 120 satisfies: 2%<X%<6%.

[0121] In this embodiment, the range of the mass percentage of cerium in the permanent magnet 120 is further limited so that the mass percentage of cerium in the permanent magnet 120 satisfies: 2%<X%<6%. This setting takes into account both the performance of the motor 10 and the production cost of the motor 10.

[0122] That is, adding the relatively inexpensive and abundant cerium to the permanent magnet 120 can reduce the use of expensive and scarce heavy rare earth elements, thereby lowering the production cost of the motor 10. In other words, the cost of the permanent magnet 120 can be reduced while maintaining the performance of the motor 10, thereby improving the cost-effectiveness of the motor 10.

[0123] If the mass percentage of cerium in the permanent magnet 120 is greater than or equal to 6%, the coercive force of the permanent magnet 120 decreases, which will reduce the magnetic energy product of the permanent magnet 120 and weaken the magnetic properties of the rotor 100, thereby affecting the anti-demagnetization ability and efficiency of the motor 10, causing demagnetization of the rotor 100 during operation, and reducing the reliability and stability of the motor 10.

[0124] If the mass percentage of cerium in the permanent magnet 120 is less than or equal to 2%, the degree of replacement of praseodymium with neodymium is limited, which limits the extent of reducing the production cost of the motor 10.

[0125] In some embodiments, the mass percentage of cerium in the permanent magnet 120 includes 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, etc., which are not listed here one by one.

[0126] In some embodiments, the maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

[0127] In this embodiment, the value of the maximum allowable operating voltage of the power device of the controller of the motor 10 is further limited.

[0128] For example, the maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

[0129] The power devices of the controller of the motor 10 include, but are not limited to, SiC (silicon carbide) power devices, IGBT (Insulated Gate Bipolar Transistor) and GaN (gallium nitride) power devices.

[0130] The maximum allowable operating voltage of the power device of the controller is equal to 650V, or the maximum allowable operating voltage of the power device of the controller is equal to 1200V. At this time, the efficiency of the controller of the motor 10 is relatively high. When the maximum allowable operating voltage of the power device is 650V, it can be used in situations where the rated output DC voltage of the battery pack is 500V and below. When the maximum allowable operating voltage of the power device is 1200V, it can be used in situations where the rated output DC voltage of the battery pack is 800V and below. The voltage resistance levels of power devices with a maximum allowable operating voltage of 650V and power devices with a maximum allowable operating voltage of 1200V can cover the current common new energy electric vehicle application scenarios, and can give full play to the efficiency advantages of the motor 10.

[0131] In some embodiments, the residual magnetic flux density Br of the permanent magnet 120 at 20° C. satisfies: 1.2T≤Br≤1.5T.

[0132] In this embodiment, the structure of the permanent magnet 120 is further defined so that the residual magnetic flux density of the permanent magnet 120 at 20°C is denoted as Br, Br is greater than or equal to 1.2 T, and Br is less than or equal to 1.5 T. This configuration ensures that the magnetic field strength of the rotor 100 is within a reasonable range. Since the magnetic field of the rotor 100 is not adjustable, if the residual magnetic flux density Br of the permanent magnet 120 at 20°C is greater than 1.5 T, the high-speed field-weakening operation of the motor 10 will be limited. If the residual magnetic flux density Br of the permanent magnet 120 at 20°C is less than 1.2 T, the motor 10 will not be able to provide sufficient output capacity.

[0133] Illustratively, the values ​​of the residual magnetic flux density Br of the permanent magnet 120 at 20° C. include: 1.25 T, 1.3 T, 1.34 T, 1.4 T, 1.46 T, etc., which are not listed here one by one.

[0134] In some embodiments, the intrinsic coercivity Hcj of the permanent magnet 120 at 20° C. satisfies: 21.3 kOe≤Hcj≤25.2 kOe.

[0135] In this embodiment, the structure of the permanent magnet 120 is further defined such that the intrinsic coercivity of the permanent magnet 120 at 20°C, denoted as Hcj, is greater than or equal to 21.3 kOe and less than or equal to 25.2 kOe. The intrinsic coercivity of the permanent magnet 120 is a key indicator for measuring the demagnetization resistance of the permanent magnet 120. If Hcj is less than 21.3 kOe, the demagnetization resistance of the permanent magnet 120 is weak, and irreversible demagnetization may occur during operation of the motor 10. If Hcj is greater than 25.2 kOe, the use of heavy rare earth elements increases, significantly increasing costs and hindering the cost-effectiveness of the motor 10.

[0136] According to some further embodiments of the present application, a compressor includes: a motor 10 as described in any of the above embodiments.

[0137] In this embodiment, the compressor includes a motor 10 .

[0138] The motor 10 includes a rotor 100 and a stator 200 .

[0139] The rotor 100 includes a rotor core 110 and a plurality of permanent magnets 120 . The rotor core 110 is provided with a plurality of magnet slot groups 130 . Each magnet slot group 130 is provided with a permanent magnet 120 . The permanent magnet 120 contains X% cerium by mass.

[0140] The stator 200 includes a stator core 210 and a winding 220 . The stator core 210 includes a plurality of stator teeth 212 . The winding 220 is wound around the plurality of stator teeth 212 .

[0141] The weight of the plurality of permanent magnets 120 is recorded as Mp, the weight of the winding 220 is recorded as Mc, the back electromotive force value of the motor 10 at a speed of 1000 rpm is recorded as Ke, and the maximum allowable operating voltage of the power device of the controller of the motor 10 is recorded as Ub.

[0142] Among them, using the permanent magnet 120 containing cerium as the magnetic pole can reduce the content of praseodymium and neodymium elements in the permanent magnet 120. In this way, the production cost of the permanent magnet 120 can be reduced, and then the production cost of the motor 10 can be reduced, solving the problem in the related art that the cost of the motor 10 is high due to the high price of rare earth materials such as praseodymium and neodymium.

[0143] By replacing the relatively expensive praseodymium and neodymium elements in the permanent magnet 120 with the abundant and relatively cheap cerium element, the price of the permanent magnet 120 can be effectively reduced, thereby improving the cost-effectiveness of the motor 10. However, the introduction of the cerium element will reduce the coercive force of the permanent magnet 120 to a certain extent, thereby reducing the magnetic energy product of the permanent magnet 120, and weakening the magnetic properties of the rotor 100. In order to ensure that the air gap composite magnetic field remains unchanged, the magnetic field strength of the stator 200 is usually increased by increasing the amount of windings 220 of the stator 200. At the same time, the operation of the motor 10 is usually regulated by a controller, and once the model of the power device in the controller is determined, the maximum operating voltage of the power device is determined accordingly. Since the rotor 100 magnetic field provided by the permanent magnet 120 of the motor 10 is not adjustable, in order to prevent the load voltage of the motor 10 from exceeding the allowable value of the power device at high speed, weak magnetic control is usually required. Simply increasing the magnetic field strength of stator 200 to compensate for the loss of the air gap composite magnetic field will exacerbate the armature reaction of stator 200, hindering the output capacity of motor 10 during high-speed field weakening, thereby limiting the operating range of the compressor. This requires a matching and balanced design of the stator and rotor magnetic fields of motor 10, and reasonable adjustment of the material usage of motor 10's permanent magnets 120, windings 220, and other materials. Within the constraints of the maximum operating voltage of the power devices, the design value of motor 10's back EMF meets the motor 10's field weakening overload capacity, thereby improving the cost-effectiveness of motor 10.

[0144] It can be understood that when the load is symmetrical, the effect of the armature magnetomotive force on the fundamental wave of the main pole magnetic field is the armature reaction. The armature reaction will affect the performance of the motor 10. The influence of the armature reaction can be reduced from two aspects. First, the magnetic field of the stator 200 is weakened. Second, the magnetic field of the rotor 100 is enhanced. The magnetic field of the stator 200 is correlated with the parameters of the winding 220 wound on the stator teeth 212 of the stator core 210. The magnetic field of the rotor 100 is correlated with the parameters of the permanent magnet 120. Therefore, by optimizing the relationship between the weight Mp of multiple permanent magnets 120 and the weight Mc of the winding 220, the air gap synthetic magnetic field can be in a balanced state. In this way, the output capacity of the motor 10 at high speed and weak magnetic field can be improved, which is conducive to reducing the armature reaction.

[0145] It is understood that permanent magnets 120 contain cerium, and the amount of cerium used can also affect the magnetic field of rotor 100. If the mass percentage of cerium in permanent magnets 120 is too high, it will not be conducive to improving the magnetic field of rotor 100 and may aggravate armature reaction. If the mass percentage of cerium in permanent magnets 120 is too low, the production cost of rotor 100 will still be high.

[0146] It is understood that the back EMF value Ke of the motor 10 at 1000 rpm is correlated with the maximum allowable operating voltage Ub of the power devices of the controller of the motor 10. If the back EMF value Ke of the motor 10 at 1000 rpm is too high, the power devices may be easily broken down. If the back EMF value Ke of the motor 10 at 1000 rpm is too low, the performance of the motor 10 may not be effectively utilized.

[0147] Therefore, by rationally setting the relationship between the mass percentage X% of cerium in each permanent magnet 120, the weight Mp of the multiple permanent magnets 120, the weight Mc of the winding 220, the maximum allowable operating voltage Ub of the power components of the motor 10 controller, and the back EMF value Ke of the motor 10 at 1000 rpm, so that the following is satisfied: (Mp / Mc) × Ub × X% ≤ Ke, the cost-effectiveness of the motor 10 can be improved while reducing the impact of the armature reaction under load. This helps enhance the load capacity of the motor 10 under high-speed field-weakening conditions and reduces the production cost of the motor 10. Consequently, by using permanent magnets 120 with a higher cerium content, the praseodymium and neodymium content in the permanent magnets 120 can be reduced, achieving even greater cost reduction and efficiency improvement.

[0148] According to some further embodiments of the present application, a vehicle includes: a compressor as described in the above embodiments.

[0149] In this embodiment, the vehicle includes a compressor.

[0150] The compressor includes a motor 10 .

[0151] The motor 10 includes a rotor 100 and a stator 200 .

[0152] The rotor 100 includes a rotor core 110 and a plurality of permanent magnets 120 . The rotor core 110 is provided with a plurality of magnet slot groups 130 . Each magnet slot group 130 is provided with a permanent magnet 120 . The permanent magnet 120 contains X% cerium by mass.

[0153] The stator 200 includes a stator core 210 and a winding 220 . The stator core 210 includes a plurality of stator teeth 212 . The winding 220 is wound around the plurality of stator teeth 212 .

[0154] The weight of the plurality of permanent magnets 120 is recorded as Mp, the weight of the winding 220 is recorded as Mc, the back electromotive force value of the motor 10 at a speed of 1000 rpm is recorded as Ke, and the maximum allowable operating voltage of the power device of the controller of the motor 10 is recorded as Ub.

[0155] Among them, using the permanent magnet 120 containing cerium as the magnetic pole can reduce the content of praseodymium and neodymium elements in the permanent magnet 120. In this way, the production cost of the permanent magnet 120 can be reduced, and then the production cost of the motor 10 can be reduced, solving the problem in the related art that the cost of the motor 10 is high due to the high price of rare earth materials such as praseodymium and neodymium.

[0156] By replacing the relatively expensive praseodymium and neodymium elements in the permanent magnet 120 with the abundant and relatively cheap cerium element, the price of the permanent magnet 120 can be effectively reduced, thereby improving the cost-effectiveness of the motor 10. However, the introduction of the cerium element will reduce the coercive force of the permanent magnet 120 to a certain extent, thereby reducing the magnetic energy product of the permanent magnet 120, and weakening the magnetic properties of the rotor 100. In order to ensure that the air gap composite magnetic field remains unchanged, the magnetic field strength of the stator 200 is usually increased by increasing the amount of windings 220 of the stator 200. At the same time, the operation of the motor 10 is usually regulated by a controller, and once the model of the power device in the controller is determined, the maximum operating voltage of the power device is determined accordingly. Since the rotor 100 magnetic field provided by the permanent magnet 120 of the motor 10 is not adjustable, in order to prevent the load voltage of the motor 10 from exceeding the allowable value of the power device at high speed, weak magnetic control is usually required. Simply increasing the magnetic field strength of stator 200 to compensate for the loss of the air gap composite magnetic field will exacerbate the armature reaction of stator 200, hindering the output capacity of motor 10 during high-speed field weakening, thereby limiting the operating range of the compressor. This requires a matching and balanced design of the stator and rotor magnetic fields of motor 10, and reasonable adjustment of the material usage of motor 10's permanent magnets 120, windings 220, and other materials. Within the constraints of the maximum operating voltage of the power devices, the design value of motor 10's back EMF meets the motor 10's field weakening overload capacity, thereby improving the cost-effectiveness of motor 10.

[0157] It can be understood that when the load is symmetrical, the effect of the armature magnetomotive force on the fundamental wave of the main pole magnetic field is the armature reaction. The armature reaction will affect the performance of the motor 10. The influence of the armature reaction can be reduced from two aspects. First, the magnetic field of the stator 200 is weakened. Second, the magnetic field of the rotor 100 is enhanced. The magnetic field of the stator 200 is correlated with the parameters of the winding 220 wound on the stator teeth 212 of the stator core 210. The magnetic field of the rotor 100 is correlated with the parameters of the permanent magnet 120. Therefore, by optimizing the relationship between the weight Mp of multiple permanent magnets 120 and the weight Mc of the winding 220, the air gap synthetic magnetic field can be in a balanced state. In this way, the output capacity of the motor 10 at high speed and weak magnetic field can be improved, which is conducive to reducing the armature reaction.

[0158] It is understood that permanent magnets 120 contain cerium, and the amount of cerium used can also affect the magnetic field of rotor 100. If the mass percentage of cerium in permanent magnets 120 is too high, it will not be conducive to improving the magnetic field of rotor 100 and may aggravate armature reaction. If the mass percentage of cerium in permanent magnets 120 is too low, the production cost of rotor 100 will still be high.

[0159] It is understood that the back EMF value Ke of the motor 10 at 1000 rpm is correlated with the maximum allowable operating voltage Ub of the power devices of the controller of the motor 10. If the back EMF value Ke of the motor 10 at 1000 rpm is too high, the power devices may be easily broken down. If the back EMF value Ke of the motor 10 at 1000 rpm is too low, the performance of the motor 10 may not be effectively utilized.

[0160] Therefore, by rationally setting the relationship between the mass percentage X% of cerium in each permanent magnet 120, the weight Mp of the multiple permanent magnets 120, the weight Mc of the winding 220, the maximum allowable operating voltage Ub of the power components of the motor 10 controller, and the back EMF value Ke of the motor 10 at 1000 rpm, so that the following is satisfied: (Mp / Mc) × Ub × X% ≤ Ke, the cost-effectiveness of the motor 10 can be improved while reducing the impact of the armature reaction under load. This helps enhance the load capacity of the motor 10 under high-speed field-weakening conditions and reduces the production cost of the motor 10. Consequently, by using permanent magnets 120 with a higher cerium content, the praseodymium and neodymium content in the permanent magnets 120 can be reduced, achieving even greater cost reduction and efficiency improvement.

[0161] It is worth noting that the vehicle can be a new energy vehicle, which includes pure electric vehicles, extended-range electric vehicles, hybrid electric vehicles, fuel cell electric vehicles, hydrogen engine vehicles, etc.

[0162] The motor 10 includes a stator 200 and a rotor 100. The stator 200 includes a stator core 210 and windings 220. The rotor 100 includes a rotor core 110, a plurality of permanent magnets 120, and a shaft. The rotor core 110 is provided with a plurality of magnet slot groups 130, a plurality of slot groups 140, and an axial hole. The stator core 210 includes an annular yoke and a plurality of stator teeth 212. The plurality of stator teeth 212 are arranged at intervals around the axis of the stator core 210. Each stator tooth 212 is connected to the inner circumferential wall of the annular yoke. Adjacent stator teeth 212 and the annular yoke enclose a plurality of stator slots. Windings 220 are placed in the stator slots and wound around the stator teeth 212. The plurality of magnet slot groups 130 are arranged at intervals around the axis of the rotor core 110. Permanent magnets 120 are placed in magnet slot groups 130 and contain X% cerium (Ce) by mass. Slot groups 140 are arranged in the magnetic pole portion formed between the outer circumferential wall of rotor core 110 and magnet slot groups 130. Slot groups 140 include an odd number of slots 142, which are asymmetrically arranged about a magnetic pole centerline 150.

[0163] The weight of the plurality of permanent magnets 120 is recorded as Mp, the weight of the winding 220 is recorded as Mc, the back electromotive force value of the motor 10 at a speed of 1000 rpm is recorded as Ke, and the maximum allowable operating voltage of the power device used in the controller of the motor 10 is recorded as Ub.

[0164] The slit group 140 includes two first slits 144, and the two first slits 144 are symmetrically arranged with the magnetic pole center line 150 as the symmetry axis. The first slit 144 includes a first end 1442 and a second end 1444. The first ends 1442 of the two first slits 144 are adjacent to each other, and the second ends 1444 of the two first slits 144 are far away from each other. The second end 1444 is located between the first end 1442 and the magnet slot group 130. The angle formed between the two first slits 144 is recorded as α.

[0165] The magnet slot group 130 includes two slot bodies 132, and the slot body 132 includes a third end 1322 and a fourth end 1324. The third ends 1322 of the two slot bodies 132 are far away from each other, and the fourth ends 1324 of the two slot bodies 132 are adjacent to each other. The fourth end 1324 is located between the third end 1322 and the axis of the rotor core 110; the angle formed between the first slit 144 and the slot body 132 on the same side of the magnetic pole centerline 150 is recorded as β.

[0166] The stator tooth 212 includes a tooth body 2122 and a tooth shoe 2124 . The tooth shoe 2124 is connected to the circumferential end surface of the tooth body 2122 . The circumferential width of the tooth body 2122 is denoted as B.

[0167] Among them, H<α / β×Bt≤3.4mm, 1.5mm≤H≤2mm.

[0168] The weight of the rotor core 110 is denoted as Mr, where 0.17≤Mp / Mr≤0.26.

[0169] The mass percentage of cerium in the permanent magnet 120 satisfies: 2%<X%<6%.

[0170] Each slit group 140 includes two first slits 144 and a second slit 146. One first slit 144 and the second slit 146 are parallel to each other and are located on a first side of the magnetic pole centerline 150, while the other first slit 144 is located on a second side of the magnetic pole centerline 150. The two first slits 144 are symmetrically arranged with the magnetic pole centerline 150 as the axis of symmetry.

[0171] The rotor 100 rotates from the second side of the magnetic pole centerline 150 to the first side of the magnetic pole centerline 150. In other words, the first side of the magnetic pole centerline 150 is the windward side, and the second side of the magnetic pole centerline 150 is the leeward side.

[0172] The power devices of the controller include but are not limited to IGBT, SIC, and GaN, and the Ub of the power devices is 650V or 1200V.

[0173] The residual magnetic flux density Br of the permanent magnet 120 at 20° C. satisfies: 1.2T≤Br≤1.5T.

[0174] The intrinsic coercive force Hcj of the permanent magnet 120 at 20° C. satisfies: 21.3 kOe≤Hcj≤25.2 kOe.

[0175] The motor 10 of the present application can improve cost performance while reducing the impact of armature reaction when the motor 10 is loaded, and enhance the load-carrying capacity of the motor 10 at high speed and weak magnetic field.

[0176] The slit group 140 includes two first slits 144, which are symmetrically arranged with the magnetic pole center line 150 as the symmetry axis. The first slit 144 includes a first end 1442 and a second end 1444. The first ends 1442 of the two first slits 144 are adjacent to each other, and the second ends 1444 of the two first slits 144 are separated from each other. The second end 1444 is located between the first end 1442 and the magnet slot group 130. The angle formed between the two first slits 144 is recorded as α. The magnet slot group 130 includes two slot bodies 132, and the slot body 132 includes a third end 1322 and a fourth end 1324. The two slot bodies The third ends 1322 of the two slot bodies 132 are spaced apart from each other, and the fourth ends 1324 of the two slot bodies 132 are adjacent to each other. The fourth ends 1324 are located between the third ends 1322 and the axis of the rotor core 110. The angle formed between the first slot 144 and the slot body 132 on the same side of the magnetic pole centerline 150 is denoted as β. The stator teeth 212 include tooth bodies 2122 and tooth boots 2124. The tooth boots 2124 are connected to the circumferential end faces of the tooth bodies 2122. The circumferential width of the tooth bodies 2122 is denoted as Bt. The circumferential width of the permanent magnets 120 is denoted as H. Where H < α / β × Bt ≤ 3.4 mm, and 1.5 mm ≤ H ≤ 2 mm. This configuration can reduce the no-load cogging torque and load torque pulsation of the motor 10, while ensuring that the magnetic field at the stator core 210 does not oversaturate, thereby improving the output capacity of the motor 10.

[0177] The weight of the rotor core 110 is recorded as Mr, where 0.17≤Mp / Mr≤0.26. This setting can ensure that the permanent magnetic field strength of the rotor 100 is within a reasonable range and improve the torque output capacity of the motor 10.

[0178] The mass percentage of cerium in permanent magnet 120 satisfies the following conditions: 2% ≤ X% ≤ 6%. Adding relatively inexpensive and abundant cerium to permanent magnet 120 reduces the use of expensive and scarce heavy rare earth elements, thereby lowering costs. However, if the mass percentage of cerium in permanent magnet 120 is greater than or equal to 6%, the coercive force of permanent magnet 120 will be severely reduced, leading to demagnetization of rotor 100 during operation and reduced reliability of motor 10. If the mass percentage of cerium in permanent magnet 120 is less than 2%, there will be no significant cost improvement.

[0179] Each slit group 140 includes three slits 142, each of which is composed of two first slits 144 and one second slit 146. One first slit 144 and the second slit 146 are parallel to each other and are placed on the first side of the magnetic pole centerline 150, while the other first slit 144 is placed on the second side of the magnetic pole centerline 150. The two first slits 144 are symmetrically arranged with the magnetic pole centerline 150 as the axis of symmetry. The second slit 146 is located on one side of the two first slits 144. The first side of the magnetic pole centerline 150 is the windward side, and the second side of the magnetic pole centerline 150 is the leeward side. This arrangement can reduce the no-load cogging torque and load electromagnetic torque pulsation of the motor 10.

[0180] The power devices of the controller include but are not limited to IGBT, SIC, and GaN, and the Ub of the power devices is 650V or Ub = 1200V. At this time, the efficiency of the controller of the motor 10 is relatively high. When the power device is 650V, it can be used in situations where the rated output DC voltage of the battery pack is 500V and below. When the power device is 1200V, it can be used in situations where the rated output DC voltage of the battery pack is 800V and below. The voltage resistance levels of 650V power devices and 1200V power devices can cover the application scenarios of new energy electric vehicles, and can give full play to the efficiency advantages of the motor 10 and the power devices themselves.

[0181] The residual magnetic flux density Br of the permanent magnet 120 at 20°C satisfies the following conditions: 1.2T ≤ Br ≤ 1.5T. This setting ensures that the magnetic field strength of the rotor 100 remains within a reasonable range. If Br is greater than 1.5T, the high-speed field-weakening operation of the motor 10 will be limited due to the unadjustable magnetic field of the rotor 100. If Br is less than 1.2T, sufficient output capacity cannot be provided.

[0182] The intrinsic coercivity Hcj of the permanent magnet 120 at 20°C satisfies the following conditions: 21.3 kOe ≤ Hcj ≤ 25.2 kOe. The intrinsic coercivity of the permanent magnet 120 is a key indicator of its resistance to demagnetization. If Hcj is lower than 21.3 kOe, the permanent magnet 120's resistance to demagnetization is weak, and irreversible demagnetization may occur during operation of the motor 10. If Hcj is higher than 25.2 kOe, the use of heavy rare earth elements increases, significantly increasing costs and hindering the cost-effectiveness of the motor 10.

[0183] The load capacity of motor 10 during high-speed field weakening can be characterized by the output torque of motor 10. A simulation is performed using a 12-slot, 8-pole motor as an example to calculate the torque of motor 10 under field weakening conditions at maximum current and maximum speed. FIG3 shows a curve showing the relationship between the maximum torque values ​​of motor 10 according to one embodiment of the present application. Taking X% = 2% and Ub = 650V as an example, when (Mp / Mc) × Ub × X% ≤ Ke is satisfied, the torque output capacity of motor 10 is high and meets product requirements. At this time, the armature reaction of motor 10 under high-speed field weakening conditions is weak, and motor 10 has a strong load capacity. The dotted line in the figure represents the product's usage requirements.

[0184] FIG4 is a graph comparing the cogging torque values ​​of a motor of the related art (the motor is not provided with the slit group of the present application) and the motor 10 of the present application.

[0185] In some embodiments, taking α=34°, β=107.5°, Bt=8.1mm, and H=2mm as an example, the no-load cogging torque of the present application is 0.21Nm, and the no-load cogging torque of the motor in the related art is 0.98Nm. It can be seen that the cogging torque of the motor 10 of the present application is only 21.4% of the cogging torque of the motor in the related art, and the cogging torque is significantly reduced.

[0186] Figure 5 is a schematic diagram of the load torque pulsation of the present application. The angle formed between the two first slits 144 is denoted as α, the angle formed between the first slit 144 and the slot 132 on the same side of the magnetic pole centerline 150 is denoted as β, the circumferential width of the tooth body 2122 of the stator tooth 212 is denoted as Bt, and the circumferential width of the permanent magnet 120 is denoted as H. Here, H < α / β × Bt ≤ 3.4 mm, and 1.5 mm ≤ H ≤ 2 mm. Taking H = 1.8 as an example, the torque pulsation of the motor 10 does not exceed 5%, which is at a low level. The motor 10 can operate smoothly at high speed with low vibration and noise.

[0187] Figure 6 is a graph of the rotor flux and stator armature flux of motor 10 at maximum load. The difference between the rotor flux and the stator armature flux quantitatively describes the degree of loaded armature reaction of motor 10. A strong armature magnetic field leads to a deeper field weakening depth at high speeds of motor 10, resulting in a sharp drop in torque output. A strong permanent magnet field of rotor 100 limits high-speed operation of motor 10. The weight of rotor core 110 is denoted as Mr, where 0.17 ≤ Mp / Mr ≤ 0.26. The absolute value of the difference between the rotor flux and the stator armature flux does not exceed 20%. This maintains a relatively balanced magnetic field between the stator 200 and rotor 100 of motor 10, facilitating field weakening at high speeds and improving the motor's high-speed field weakening output capability.

[0188] That is to say, the present application can improve the cost-effectiveness by reasonably setting the structure of the motor 10, reduce the influence of the armature reaction when the motor 10 is loaded, and enhance the load-carrying capacity of the motor 10 at high speed and weak magnetic field.

[0189] Exemplarily, the stator core 210 includes: a first punching group; a second punching group, stacked on one side of the first punching group along the axial direction of the stator core 210, and closer to the end of the stator core 210 than the first punching group; either the first punching group or the second punching group includes an annular yoke and a plurality of teeth, each tooth connected to the inner circumferential wall of the annular yoke, the plurality of teeth being spaced apart around the axis of the stator core 210, with any two adjacent teeth and the annular yoke enclosing a stator slot; along the circumference of the stator core 210, the slot width of the stator slot of the first punching group is denoted as d1, and the slot width of the stator slot of the second punching group is denoted as d2, where 1<d2 / d1<3. Each stator tooth 212 includes one tooth of the first punching group and one tooth of the second punching group.

[0190] The first punching sheet group and the second punching sheet group are arranged along the axial direction of the stator core 210 .

[0191] In some embodiments, along the axial direction of the stator core 210 , the second punching sheet group is stacked on one side of the first punching sheet group.

[0192] The first punching sheet group includes an annular yoke and multiple teeth. Any one of the multiple teeth is connected to the inner circumferential wall of the annular yoke. The multiple teeth are arranged at intervals around the axis of the stator core 210. Any two adjacent teeth and the annular yoke enclose a stator slot.

[0193] The second punching sheet group includes an annular yoke and multiple teeth. Any one of the multiple teeth is connected to the inner circumferential wall of the annular yoke. The multiple teeth are arranged at intervals around the axis of the stator core 210. Any two adjacent teeth and the annular yoke enclose a stator slot.

[0194] The structures of the first punching sheet group and the second punching sheet group are defined so that the width of the stator slot openings of the first punching sheet group in the circumferential direction of the stator core 210 is recorded as d1, and the width of the stator slot openings of the second punching sheet group in the circumferential direction of the stator core 210 is recorded as d2, and the relationship between d1 and d2 is defined so as to satisfy: 1<d2 / d1<3.

[0195] It is understood that under symmetrical load, the effect of the armature magnetomotive force on the fundamental wave of the main pole magnetic field is the armature reaction. The armature reaction will affect the performance of the motor 10. The present application rationally arranges the structure of the stator core 210 so that the first and second punching groups have different slot widths in the circumferential direction of the stator core 210. This improves the armature reaction of the motor 10, reduces the voltage of the armature reaction of the motor 10, and improves the torque output of the motor 10 under high-speed conditions.

[0196] If d2 / d1 is less than or equal to 1, the difference between the slot width of the first punching sheet group in the circumferential direction of the stator core 210 and the slot width of the second punching sheet group in the circumferential direction of the stator core 210 is small, that is, the slot width of the first punching sheet group in the circumferential direction of the stator core 210 is closer to the slot width of the second punching sheet group in the circumferential direction of the stator core 210. In this way, the effect of alleviating the armature reaction is poor, and the effect of improving the torque output of the motor 10 under high-speed conditions is poor.

[0197] If d2 / d1 is greater than or equal to 3, the width of the stator slots of the second punching group in the circumferential direction of the stator core 210 is too large. This makes it impossible to effectively block the windings 220 wound around the teeth of the first and second punching groups, and the windings 220 are likely to separate from the teeth, thus failing to ensure the stability and reliability of electronic motion. This setting also increases the gap between the stator and rotor of the motor 10, affecting the power density of the motor 10 and the torque output of the motor 10.

[0198] In addition, the second punching sheet group is closer to the end of the stator core 210 than the first punching sheet group, that is, the distance from the second punching sheet group to the end of the stator core 210 is smaller than the distance from the first punching sheet group to the end of the stator core 210, and the width d1 of the stator slot opening of the first punching sheet group in the circumferential direction of the stator core 210 and the width d2 of the stator slot opening of the second punching sheet group in the circumferential direction of the stator core 210 satisfy 1<d2 / d1<3. In other words, along the circumference of the stator core 210, the punching sheet group with a smaller slot width is closer to the middle of the stator core 210. In this way, the problem of the slot insulation of the stator 200 protruding from the inner diameter of the stator core 210 can be effectively prevented, thereby improving the reliability of the motor 10.

[0199] For example, d1 and d2 satisfy: 1.5<d2 / d1<3. That is, the armature reaction of the motor 10 can be improved, the voltage of the armature reaction of the motor 10 can be reduced, and the torque output of the motor 10 under high-speed conditions can be improved.

[0200] For example, the number of first punching sheet groups is recorded as m, the number of second punching sheet groups is recorded as n, and one first punching sheet group is provided between any two adjacent second punching sheet groups; wherein, m≥1, n≥2.

[0201] The structure of the first and second punching groups is further defined such that the number of first punching groups is denoted as m, the number of second punching groups is denoted as n, m ≥ 1, n ≥ 2. Furthermore, a first punching group is defined as being disposed between any two adjacent second punching groups. In other words, a second punching group is disposed at each axial end face of a first punching group.

[0202] This arrangement can meet the use requirements of setting different slot widths of the first punching sheet group and the second punching sheet group in the circumferential direction of the stator core 210, and makes the number of the first punching sheet group smaller than the number of the second punching sheet group. In this way, the slot insulation of the stator 200 can be effectively prevented from protruding from the inner diameter of the stator core 210, which can improve the reliability of the motor 10 and help reduce the material input of the stator core 210, thereby helping to reduce the weight of the stator core 210 and reduce the production cost of the stator core 210.

[0203] It is understood that if the slot width of the punching lamination group in the circumferential direction of the stator core 210 is small, the magnetic flux leakage will be significantly increased, thus reducing the output torque of the motor 10. Therefore, the number of the first punching lamination group is smaller than the number of the second punching lamination group to balance the magnetic flux leakage of the motor 10 and prevent the slot insulation of the stator 200 from protruding from the inner diameter of the stator core 210, which is beneficial to improving the safety and reliability of the motor 10.

[0204] Exemplarily, the axial height of the first punching sheet group is recorded as h1, and the axial height of the second punching sheet group is recorded as h2, wherein 0.05<(m×h1) / (n×h2)<0.2.

[0205] The structures of the first and second lamination groups are further defined so that along the axial direction of the stator core 210, the height of the first lamination group is denoted as h1 and the height of the second lamination group is denoted as h2, and the relationship between h1 and h2 is defined so as to satisfy: 0.05 < (m×h1) / (n×h2) < 0.2. In other words, the relationship between the sum of the axial heights of all first lamination groups included in the stator core 210 and the sum of the axial heights of all second lamination groups included in the stator core 210 is defined. Because reducing the slot width of the second lamination group in the circumferential direction of the stator core 210 increases the risk of magnetic flux leakage in the stator 200, by defining the optimal ratio of the axial heights of the first and second lamination groups, the risk of magnetic flux leakage can be minimized to the greatest extent possible, that is, magnetic flux leakage can be reduced while ensuring the performance of the motor 10.

[0206] Exemplarily, the stator core 210 further includes: a third punching sheet group, the second punching sheet group is located between the first punching sheet group and the third punching sheet group; the third punching sheet group includes an annular yoke and a plurality of teeth, and along the circumference of the stator core 210, the slot width of the stator slot of the third punching sheet group is recorded as d3, wherein d3>d2>d1.

[0207] The structure of the stator core 210 is further limited so that the stator core 210 also includes a third punching group. Along the axial direction of the stator core 210, the second punching group is located between the first punching group and the third punching group. In other words, the third punching group is located at the end of the stator core 210.

[0208] The third punching sheet group includes an annular yoke and multiple teeth. Any one of the multiple teeth is connected to the inner circumferential wall of the annular yoke. The multiple teeth are arranged at intervals around the axis of the stator core 210. Any two adjacent teeth and the annular yoke enclose a stator slot.

[0209] The structures of the first, second, and third punching laminations are defined so that the width of the stator slot openings of the first punching lamination group in the circumferential direction of the stator core 210 is denoted as d1, the width of the stator slot openings of the second punching lamination group in the circumferential direction of the stator core 210 is denoted as d2, and the width of the stator slot openings of the third punching lamination group in the circumferential direction of the stator core 210 is denoted as d3. The relationship among d1, d2, and d3 is defined so as to satisfy: d3>d2>d1. In other words, along the axial direction of the stator core 210, the width of the slot openings of the first, second, and third punching lamination groups in the circumferential direction of the stator core 210 gradually increases. This configuration can reduce magnetic leakage and improve the output torque of the motor 10. In other words, the first punching sheet group, the second punching sheet group and the third punching sheet group are provided with different slot widths in the circumferential direction of the stator core 210. This can improve the armature reaction of the motor 10, reduce the voltage of the armature reaction of the motor 10, and improve the torque output of the motor 10 under high-speed conditions.

[0210] It can be understood that the first punching sheet group with a smaller slot width in the circumferential direction of the stator core 210 is located in the middle of the stator core 210, and the third punching sheet group with a larger slot width in the circumferential direction of the stator core 210 is located at the end of the stator core 210. In this way, the problem of the slot insulation of the stator 200 protruding from the inner diameter of the stator core 210 can be effectively prevented, thereby improving the reliability of the motor 10.

[0211] In other words, this arrangement takes into account both the leakage flux of the motor 10 and the blocking of the slot insulation of the stator 200 from protruding from the inner diameter of the stator core 210, which is beneficial to improving the safety and reliability of the use of the motor 10.

[0212] Illustratively, along the axial direction of the stator core 210 , the orthographic projection of the slot wall of the stator slot of the third punching sheet group on the second punching sheet group is located outside the slot wall of the stator slot of the second punching sheet group.

[0213] The cross-sectional area of ​​the stator slots of the third lamination group is greater than the cross-sectional area of ​​the stator slots of the second lamination group. That is, the slot walls of the stator slots of the third lamination group and the second lamination group enclose a sunken groove, that is, at least a portion of the slot walls of the stator slots of the third lamination group and the slot walls of the stator slots of the second lamination group form a stepped structure.

[0214] In some embodiments, the stator 200 further includes an insulating bracket. When the stator core 210 is coupled to the insulating bracket, an insulating protrusion is provided on the insulating bracket. The insulating protrusion abuts within the recessed groove and can wrap around the edge of the stator slot of the third lamination group. This allows the stator 200 to be lowered axially along the stator core 210 while maintaining the performance of the motor 10. This helps reduce the internal space occupied by the stator 200, thereby reducing the size and weight of the motor 10.

[0215] Furthermore, this arrangement is beneficial for increasing the matching area and matching angle between the insulating bracket and the stator core 210 , and is beneficial for improving the stability and reliability of the matching between the insulating bracket and the stator core 210 .

[0216] In addition, this arrangement can shorten the length of each turn of the winding 220, reduce the amount of winding 220 used, and reduce the production cost of the product.

[0217] Exemplarily, the wall surface of the tooth portion facing the axis of the stator core 210 is the tooth surface; the tooth surface of at least one of the first punching group, the second punching group and the third punching group includes an arc segment and a connecting segment, and the connecting segment is connected to one side of the arc segment in the circumferential direction of the stator core 210, and the arc segment is closer to the axis of the stator core 210 than the connecting segment.

[0218] The wall surface of the tooth portion facing the axis of the stator core 210 is the tooth surface.

[0219] The structures of the first punching sheet group, the second punching sheet group and the third punching sheet group are further defined.

[0220] In some embodiments, the tooth surface of the first punching sheet group includes an arc segment and a connecting segment, or the tooth surface of the second punching sheet group includes an arc segment and a connecting segment, or the tooth surface of the third punching sheet group includes an arc segment and a connecting segment, or the tooth surface of the first punching sheet group and the tooth surface of the second punching sheet group both include an arc segment and a connecting segment, or the tooth surface of the first punching sheet group and the tooth surface of the third punching sheet group both include an arc segment and a connecting segment, or the tooth surface of the second punching sheet group and the tooth surface of the third punching sheet group both include an arc segment and a connecting segment, or any one of the tooth surface of the first punching sheet group, the tooth surface of the second punching sheet group and the tooth surface of the third punching sheet group includes an arc segment and a connecting segment.

[0221] The connecting section is connected to one side of the circular arc section, and the connecting section and the circular arc section are arranged along the circumference of the stator core 210. The circular arc section is closer to the axis of the stator core 210 than the connecting section. That is, the distance between the circular arc section and the circumference of the stator core 210 is shorter than the distance between the connecting section and the axis of the stator core 210.

[0222] This setting realizes the tooth top chamfering of the stator core 210, which is beneficial to improving the distribution of the air gap synthetic magnetic field of the motor 10, can alleviate the armature reaction, and can enhance the torque output of the motor 10 under high-speed conditions.

[0223] Exemplarily, the connecting segment includes any one of the following or a combination thereof: a plane segment, a folded surface segment, and a curved surface segment.

[0224] The structure of the connecting segment is further defined so that the connecting segment includes any one of the following or a combination thereof: a plane segment, a folded surface segment, and a curved surface segment.

[0225] For example, the connecting segment includes a plane segment. For example, the connecting segment includes a folded surface segment. For example, the connecting segment includes a curved surface segment. For example, the connecting segment includes a plane segment and a folded surface segment. For example, the connecting segment includes a plane segment and a curved surface segment. For example, the connecting segment includes a folded surface segment and a curved surface segment. For example, the connecting segment includes a plane segment, a folded surface segment, and a curved surface segment.

[0226] This arrangement can meet the requirement that the distance between the connecting segment and the axis of the stator core 210 is greater than the distance between the arc segment and the axis of the stator core 210 , thereby improving the armature reaction.

[0227] For example, along the radial direction of the rotor 100 , the value of the minimum gap between the outer circumferential wall of the rotor 100 and the inner circumferential wall of the stator 200 is denoted as δ, where 0.08<δ / d2<0.15.

[0228] By optimizing the ratio of the slot width of the second punching sheet group to the stator-rotor gap, the power density of the motor 10 can be guaranteed, the radial force density of the motor 10 can be improved, and the noise of the motor 10 can be ensured.

[0229] If δ / d2 is less than or equal to 0.08, the air gap magnetic flux density of the motor 10 will increase, the radial force density of the motor 10 will increase, and the operating noise of the motor 10 will increase.

[0230] If δ / d2 is greater than or equal to 0.15, the magnetic resistance is large, the energy consumption of the motor 10 is large, the output torque of the motor 10 is reduced, and the performance of the motor 10 is reduced.

[0231] Exemplarily, the stator core 210 also includes a stator 200 yoke, each stator tooth 212 is connected to the inner circumferential wall of the stator 200 yoke, and multiple stator teeth 212 are arranged at intervals around the axis of the stator core 210. Any two adjacent stator teeth 212 and the stator 200 yoke enclose a stator slot, and the stator core 210 has an axial first end and a second end.

[0232] The motor 10 also includes: a first insulating frame, arranged at the first end; a second insulating frame, arranged at the second end, either the first insulating frame or the second insulating frame includes a plurality of insulating teeth, each stator tooth 212 is connected to an insulating tooth, and the insulating teeth of at least one of the first insulating frame and the second insulating frame are provided with an extension portion, and the extension portion is located at the slot opening of the stator slot; slot insulating paper, arranged in the stator slot, and the slot insulating paper abuts against the extension portion, and the extension portion can at least limit the slot insulating paper in the radial direction of the stator core 210; wherein, along the circumference of the stator core 210, the gap value of the extension portion of two adjacent insulating teeth is recorded as d01, and the slot opening width of the stator slot is recorded as T, wherein d01<T.

[0233] The first insulating frame is provided at a first end of the stator core 210, and the second insulating frame is provided at a second end of the stator core 210. Either the first insulating frame or the second insulating frame includes a plurality of insulating teeth, that is, the first insulating frame includes a plurality of insulating teeth, and the second insulating frame includes a plurality of insulating teeth, and each stator tooth 212 is connected to an insulating tooth of the first insulating frame and an insulating tooth of the second insulating frame.

[0234] The insulating teeth of the first insulating frame are provided with extension parts, or the insulating teeth of the second insulating frame are provided with extension parts, or both the insulating teeth of the first insulating frame and the insulating teeth of the second insulating frame are provided with extension parts.

[0235] After the first insulating frame, the second insulating frame, the slot insulating paper and the stator core 210 are assembled, the slot insulating paper is arranged in the stator slot, the extension portion extends into the slot opening of the stator slot, and the slot insulating paper abuts against the extension portion. The extension portion can at least limit the slot insulating paper in the radial direction of the stator core 210 to ensure the matching size of the slot insulating paper and the stator slot.

[0236] The matching structure of the first insulating frame, the second insulating frame and the stator core 210 is reasonably set, so that the gap value between the extensions of the two adjacent insulating teeth in the circumferential direction of the stator core 210 is recorded as d01, and the slot width of the stator slot in the circumferential direction of the stator core 210 is recorded as T, and the relationship between d01 and T is defined so as to satisfy d01<T. In other words, the extension located at the slot opening of the stator slot and the slot wall of the stator slot cooperate to limit the slot insulation paper. Since the gap between the extensions of the two adjacent insulating teeth in the circumferential direction of the stator core 210 is small, the extension located at the slot opening of the stator slot can effectively block the slot insulation paper, prevent the slot insulation paper from protruding from the inner diameter of the stator core 210, and avoid the occurrence of undesirable problems such as the slot insulation paper bulging inward. Furthermore, due to the presence of the extension, the width of the stator slots in the circumferential direction of the stator core 210 can be appropriately increased. This configuration can reduce magnetic flux leakage, increase the output torque of the motor 10, and improve the high-frequency overload capacity of the motor 10, thereby improving the performance and reliability of the motor 10. In other words, the stator slot walls and the extension cooperate to both reduce magnetic flux leakage from the motor 10 and prevent the inward bulge of the slot insulation paper, thereby increasing the power density of the motor 10 while ensuring the safety and reliability of the motor 10.

[0237] It is understandable that at least one of the first insulating frame and the second insulating frame is provided with an extension, that is, at least one of the first insulating frame and the second insulating frame serves as a mounting carrier for the extension, has the function of mounting and fixing the extension, and can ensure the matching size of the extension, the notch of the stator slot, and the slot insulating paper. In other words, the existing structure of the first insulating frame and the second insulating frame is rationally utilized, enriching the function of the insulating frame provided with the extension, so that the insulating frame provided with the extension has both an insulating function and a function of preventing the slot insulating paper from convexing inwardly. Moreover, this arrangement also provides structural support for increasing the notch of the stator slot, and can reduce magnetic leakage while ensuring the matching size of the slot insulating paper and the stator core 210, thereby improving the high-frequency overload capacity of the motor 10.

[0238] Exemplarily, the extension is connected to the slot wall of the stator slot. The mating structure of the extension and the stator slot is further defined so that the extension is connected to the slot wall of the stator slot. That is, the extension is located at the notch of the stator slot, and the extension and the slot wall of the stator slot are interconnected. This arrangement allows the extension and the slot wall of the stator slot to be connected as a whole. In this way, it is possible to effectively prevent the slot insulation paper from protruding from the gap between the slot wall of the stator slot and the extension, providing effective and reliable structural support to ensure the safety and reliability of the use of the motor 10.

[0239] Exemplarily, the insulating tooth provided with an extension portion includes a tooth body, the tooth body is provided with a slot, and the end of the stator tooth 212 is inserted into the slot; the extension portion is connected to the end face of the tooth body facing the axis of the stator core 210, and the extension portion includes two extension sections, which are arranged at intervals in the circumferential direction of the stator core 210, each extension section extends into the slot opening of a stator slot, and each extension section abuts against the slot insulation paper.

[0240] The structures of the first insulating frame and the second insulating frame are further defined so that the insulating teeth provided with the extension portion include a tooth body, the tooth body is provided with a slot, and the end of the stator tooth 212 is inserted into the slot. This arrangement is conducive to increasing the matching area of ​​the first insulating frame, the second insulating frame and the stator core 210, and can ensure the stability and reliability of the assembly of the first insulating frame, the second insulating frame and the stator core 210.

[0241] Wherein, the extension portion includes two extension sections, and the two extension sections are arranged at intervals along the circumference of the stator core 210, and either of the two extension sections is connected to the end face of the tooth body facing the axis of the stator core 210. And each extension section extends into the notch of a stator slot, that is, the two extension sections of the extension portion extend into the notches of two stator slots respectively. In other words, the notch of a stator slot is provided with two extension sections, or the notch of a stator slot is provided with four extension sections. This arrangement can increase the abutment area between the extension portion and the slot insulation paper, and ensure the balance and consistency of the abutment between the extension portion and the slot insulation paper, avoiding the situation where one side of the circumference of the slot insulation paper abuts against the extension portion, and the other side of the circumference of the slot insulation paper is separated from the extension portion, which easily leads to the inward convexity of the slot insulation paper.

[0242] In addition, the extension part is connected to the end face of the tooth body facing the axis of the stator core 210. This arrangement can not only meet the use requirement of the extension part being located at the slot opening of the stator slot, but also reduce the occupancy rate of the extension part on the internal space of the stator slot.

[0243] Exemplarily, when the insulating teeth of either the first insulating frame or the second insulating frame are provided with extensions, along the circumference of the stator core 210 , the gap value of the extensions of two adjacent insulating teeth of the first insulating frame is equal to the gap value of the extensions of two adjacent insulating teeth of the second insulating frame.

[0244] The structures of the first and second insulating frames are further defined. When the insulating teeth of the first insulating frame are provided with extensions, and the insulating teeth of the second insulating frame are provided with extensions, the gap between the extensions of two adjacent insulating teeth of the first insulating frame and the gap between the extensions of two adjacent insulating teeth of the second insulating frame along the circumference of the stator core 210 are equal. This reduces the processing difficulty of the first and second insulating frames, facilitates production, improves processing efficiency, and reduces product production costs.

[0245] In addition, this structural arrangement can ensure the balance and consistency of the abutment areas between the extensions of the first insulating frame and the second insulating frame and the slot insulating paper, which is beneficial to improving the effectiveness and feasibility of preventing the slot insulating paper from bulging inward.

[0246] Exemplarily, the end surface of the tooth portion facing the axis of the stator core 210 is the tooth surface; along the circumference of the stator core 210, the gap value between two adjacent tooth surfaces of the first punching sheet group is different from the gap value between two adjacent tooth surfaces of the second punching sheet group.

[0247] It is understood that under symmetrical load, the effect of the armature magnetomotive force on the fundamental wave of the main pole magnetic field is the armature reaction. This armature reaction can affect the performance of the motor 10. This application rationally configures the structure of the stator 200 so that the first and second punching lamination groups have different slot widths in the circumferential direction of the stator core 210. This improves the armature reaction of the motor 10, reduces the armature reaction voltage of the motor 10, and improves the torque output of the motor 10 under high-speed conditions.

[0248] It is understood that, along the circumference of the stator core 210, the punching sheet group with a smaller gap value between two adjacent tooth surfaces has the function of blocking the winding 220 and slot insulation paper of the stator 200, while the punching sheet group with a larger gap value between two adjacent tooth surfaces has the function of reducing magnetic leakage and increasing the output torque of the motor 10. In other words, this arrangement takes into account both the magnetic leakage of the motor 10 and the blocking of the winding 220 and slot insulation paper of the stator 200 from protruding from the inner diameter of the stator core 210, which is conducive to improving the safety and reliability of the use of the motor 10.

[0249] Illustratively, along the circumferential direction of the stator core 210 , the gap value between two adjacent tooth surfaces of the first punching sheet group is recorded as d1, and the gap value between two adjacent tooth surfaces of the second punching sheet group is recorded as d2, wherein d2>d1≥d01.

[0250] The structure of the stator core 210 is further defined so that the gap value between two adjacent tooth surfaces of the first punching group in the circumferential direction of the stator core 210 is recorded as d1, and the gap value between two adjacent tooth surfaces of the second punching group in the circumferential direction of the stator core 210 is recorded as d2, and the relationship between d1, d2 and d01 is defined so as to satisfy d2>d1≥d01. That is, the stator core 210 includes punching groups with different slot widths of the stator slots, and the smaller value d1 of the slot width is greater than or equal to the gap value d01 of the extension of two adjacent insulating teeth. The first punching group and the extension can effectively block the slot insulation paper and prevent the slot insulation paper from protruding from the inner diameter of the stator core 210. The second punching group and the first punching group can reduce leakage flux, improve the output torque of the motor 10, improve the high-frequency overload capacity of the motor 10, and help improve the performance of the motor 10 and the reliability of the motor 10.

[0251] It is understood that the second punching group is closer to the end of the stator core 210 than the first punching group. That is, the distance from the second punching group to the end of the stator core 210 is smaller than the distance from the first punching group to the end of the stator core 210. In other words, along the circumference of the stator core 210, the punching group with a smaller slot width is closer to the middle of the stator core 210. In this way, the slot insulation paper of the stator 200 can be effectively blocked, preventing the slot insulation paper from protruding from the inner diameter of the stator core 210, thereby improving the reliability of the motor 10.

[0252] For example, d1 and d2 satisfy: 1.5<d2 / d1<3. That is, the armature reaction of the motor 10 can be improved, the voltage of the armature reaction of the motor 10 can be reduced, and the torque output of the motor 10 under high-speed conditions can be improved.

[0253] If d2 / d1 is less than or equal to 1.5, the difference between the slot width of the first punching sheet group in the circumferential direction of the stator core 210 and the slot width of the second punching sheet group in the circumferential direction of the stator core 210 is small, that is, the slot width of the first punching sheet group in the circumferential direction of the stator core 210 is closer to the slot width of the second punching sheet group in the circumferential direction of the stator core 210. In this way, the effect of alleviating the armature reaction is poor, and the effect of improving the torque output of the motor 10 under high-speed conditions is poor.

[0254] If d2 / d1 is greater than or equal to 3, the width of the stator slots of the second punching group in the circumferential direction of the stator core 210 is too large. This makes it impossible to effectively block the windings 220 wound around the teeth of the first and second punching groups, and the windings 220 are likely to separate from the teeth, thus failing to ensure the stability and reliability of electronic motion. This setting also increases the gap between the stator and rotor of the motor 10, affecting the power density of the motor 10 and the torque output of the motor 10.

[0255] Exemplarily, the stator core 210 also includes: a third punching sheet group, the second punching sheet group is located between the first punching sheet group and the third punching sheet group; the third punching sheet group includes an annular yoke and a plurality of tooth portions, and along the circumferential direction of the stator core 210, the gap value between two adjacent tooth surfaces of the third punching sheet group is recorded as d3, where d3>d2.

[0256] The structure of the stator core 210 is further limited so that the stator core 210 also includes a third punching group. Along the axial direction of the stator core 210, the second punching group is located between the first punching group and the third punching group. In other words, the third punching group is located at the end of the stator core 210.

[0257] The third punching plate group includes an annular yoke and a plurality of teeth, each of which is connected to the inner circumferential wall of the annular yoke. The plurality of teeth are spaced apart around the axis of the stator core 210. The stator 200 yoke includes an annular yoke, and each stator tooth 212 includes a tooth.

[0258] The structures of the first, second, and third punching laminations are defined so that the width of the stator slot openings of the first punching lamination group in the circumferential direction of the stator core 210 is denoted as d1, the width of the stator slot openings of the second punching lamination group in the circumferential direction of the stator core 210 is denoted as d2, and the width of the stator slot openings of the third punching lamination group in the circumferential direction of the stator core 210 is denoted as d3. The relationship among d1, d2, and d3 is defined so as to satisfy: d3>d2>d1. In other words, along the axial direction of the stator core 210, the width of the slot openings of the first, second, and third punching lamination groups in the circumferential direction of the stator core 210 gradually increases. This configuration can reduce magnetic leakage and improve the output torque of the motor 10. In other words, the first punching sheet group, the second punching sheet group and the third punching sheet group are provided with different slot widths in the circumferential direction of the stator core 210. This can improve the armature reaction of the motor 10, reduce the voltage of the armature reaction of the motor 10, and improve the torque output of the motor 10 under high-speed conditions.

[0259] It can be understood that the first punching sheet group with a smaller slot width in the circumferential direction of the stator core 210 is located in the middle of the stator core 210, and the third punching sheet group with a larger slot width in the circumferential direction of the stator core 210 is located at the end of the stator core 210. In this way, the problem of the slot insulation of the stator 200 protruding from the inner diameter of the stator core 210 can be effectively prevented, thereby improving the reliability of the motor 10.

[0260] In other words, this arrangement takes into account both the leakage flux of the motor 10 and the blocking of the slot insulation of the stator 200 from protruding from the inner diameter of the stator core 210, which is beneficial to improving the safety and reliability of the use of the motor 10.

[0261] Exemplarily, on the axial end face of the rotor core 110, there is an inter-pole center line between adjacent magnet slot groups 130 in the multiple magnet slot groups 130; along the radial direction of the rotor 100, the value of the minimum gap between the outer peripheral wall of the rotor 100 and the inner peripheral wall of the stator 200 is recorded as gmin, and the minimum gap is located at the magnetic pole center line 150 of the core body, and the value of the maximum gap between the outer peripheral wall of the rotor 100 and the inner peripheral wall of the stator 200 is recorded as gmax, and the maximum gap is located at the limit center line; wherein, 0.6≤gmin / gmax≤0.8.

[0262] The structure of the rotor is further defined, wherein, on the axial end surface of the rotor core 110 , adjacent magnet slot groups 130 in the plurality of magnet slot groups 130 have inter-pole center lines between them.

[0263] The minimum clearance between the outer circumferential wall of rotor 100 and the inner circumferential wall of stator 200 in the radial direction of rotor 100 is denoted as gmin, and the maximum clearance between the outer circumferential wall of rotor 100 and the inner circumferential wall of stator 200 in the radial direction of rotor 100 is denoted as gmax. The relationship between gmin and gmax is defined to satisfy 0.6 ≤ gmin / gmax ≤ 0.8. This configuration further optimizes the back EMF waveform of motor 10, improves torque ripple under load conditions, and reduces operating noise of motor 10 and the compressor.

[0264] In some embodiments, the inter-pole centerline is also referred to as the adjacent magnetic pole centerline 150 , or q-axis for short.

[0265] Illustratively, gmin / gmax=0.62, gmin / gmax=0.64, gmin / gmax=0.66, gmin / gmax=0.68, gmin / gmax=0.7, gmin / gmax=0.72, gmin / gmax=0.74, gmin / gmax=0.76 and gmin / gmax=0.78, etc., are not listed here one by one.

[0266] In this application, the term "plurality" refers to two or more, unless otherwise specified. Terms such as "installed," "connected," "connected," and "fixed" should be interpreted broadly. For example, "connected" can mean fixed, removable, or integrally connected; and "connected" can mean directly or indirectly through an intermediary. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0267] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A motor, wherein: include: A rotor, the rotor comprising a rotor core and a plurality of permanent magnets, the rotor core being provided with a plurality of magnet slot groups, the plurality of magnet slot groups being arranged at intervals around the axis of the rotor core, each magnet slot group being provided with a permanent magnet, the permanent magnets containing X% by mass of cerium; A stator, wherein the stator comprises a stator core and a winding, the stator core comprises a plurality of stator teeth, the plurality of stator teeth are arranged at intervals around the axis of the stator core, the plurality of stator teeth enclose a mounting cavity, the rotor is rotatably disposed in the mounting cavity, and the winding is wound around the plurality of stator teeth; The weight of the plurality of permanent magnets is denoted as Mp, the weight of the winding is denoted as Mc, the back electromotive force value of the motor at a rotation speed of 1000 rpm is denoted as Ke, and the maximum allowable operating voltage of the power device of the controller of the motor is denoted as Ub, wherein, (Mp / Mc)×Ub×X%≤Ke.

2. The motor according to claim 1, wherein The Mp, the Mc, the Ub and the X% satisfy: 0.14×Ke≤(Mp / Mc)×Ub×X%≤0.69×Ke.

3. The motor according to claim 1 or 2, wherein: The weight of the rotor core is denoted as Mr, wherein 0.17≤Mp / Mr≤0.

26.

4. The electric machine according to any one of claims 1 to 3, wherein: The rotor core is further provided with a plurality of slot groups, one of which is arranged between each magnet slot group and the outer peripheral wall of the rotor core, and the slot group includes an odd number of slots.

5. The motor according to claim 4, wherein: The rotor core has a plurality of magnetic pole center lines, each of the slot groups is located at one of the magnetic pole center lines, a portion of the slots in the slot group are located on a first side of the magnetic pole center line, and another portion of the slots in the slot group are located on a second side of the magnetic pole center line.

6. The motor according to claim 5, wherein: The slit group includes two first slits, the two first slits are symmetrically arranged with the magnetic pole center line as the symmetry axis, the first slit includes a first end and a second end, the first ends of the two first slits are adjacent to each other, the second ends of the two first slits are far away from each other, the second end is located between the first end and the magnet slot group, and the angle formed between the two first slits is recorded as α; The magnet slot group includes two slot bodies, the slot bodies include a third end and a fourth end, the third ends of the two slot bodies are far away from each other, the fourth ends of the two slot bodies are close to each other, and the fourth end is located between the third end and the axis of the rotor core; The angle formed between the first slit and the slot body on the same side of the magnetic pole centerline is denoted as β; The stator tooth comprises a tooth body and a tooth shoe, wherein the tooth shoe is connected to the circumferential end surface of the tooth body, and the circumferential width of the tooth body is denoted as Bt; The circumferential width of the permanent magnet is denoted as H; Among them, H<α / β×Bt≤3.4mm, 1.5mm≤H≤2mm.

7. The motor according to claim 6, wherein: The slit group further includes a second slit, the second slit is located on a first side of the magnetic pole centerline, and the second slit is parallel to the first slit.

8. The motor according to claim 7, wherein: The two first slits are arranged adjacent to the magnetic pole center line, and the second slit is located on a side of the first slit away from the magnetic pole center line.

9. The electric machine according to any one of claims 5 to 8, wherein: The rotor rotates in a direction from the second side of the magnetic pole centerline to the first side of the magnetic pole centerline.

10. The electric machine according to any one of claims 1 to 9, wherein: The mass percentage of cerium in the permanent magnet satisfies: 2%<X%<6%.

11. The electric machine according to any one of claims 1 to 10, wherein: The residual magnetic flux density Br of the permanent magnet at 20° C. satisfies: 1.2T≤Br≤1.5T; The maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

12. The electric machine according to any one of claims 1 to 11, wherein: The intrinsic coercive force Hcj of the permanent magnet at 20° C. satisfies: 21.3 kOe≤Hcj≤25.2 kOe.

13. A compressor, wherein: include: An electric machine as claimed in any one of claims 1 to 12.

14. A vehicle, wherein: include: The compressor of claim 13.

Citation Information

Patent Citations

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