Motors, compressors and vehicles

Abstract

The present application provides a motor, a compressor, and a vehicle. The motor includes: a rotor, comprising a rotor core and a plurality of permanent magnets; the rotor core having a plurality of magnet slot groups spaced apart about the axis of the rotor core; each magnet slot group having a permanent magnet disposed therein; and a stator, comprising a stator core and a winding. The stator core includes a plurality of stator teeth spaced apart about the axis of the stator core, the plurality of stator teeth enclosing 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 speed of 1000 rpm is denoted as Ke, and the maximum allowable operating voltage of the power device of the motor controller is denoted as Ub, wherein (Mp / Mc)×Ub×X%≤Ke.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular to a motor, a compressor and a vehicle. Background Art

[0002] 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. Summary of the Invention

[0003] This application aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] To this end, a first aspect of the present application provides a motor.

[0005] A second aspect of the present application provides a compressor.

[0006] A third aspect of the present application provides a vehicle.

[0007] 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 an installation cavity, the rotor being rotatably disposed in the installation 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 motor controller being denoted as Ub, wherein (Mp / Mc)×Ub×X%≤Ke.

[0008] The present application provides a motor including a rotor and a stator.

[0009] The rotor comprises a rotor core and a plurality of permanent magnets. The rotor core is provided with a plurality of magnet slot groups. Each magnet slot group is provided with a permanent magnet. The permanent magnet contains X% of cerium by mass.

[0010] The stator includes a stator core and a winding. The stator core includes a plurality of stator teeth, and the winding is wound on the plurality of stator teeth.

[0011] The weight of the multiple permanent magnets is recorded as Mp, the weight of the winding is recorded as Mc, the back electromotive force value of the motor at a speed of 1000 rpm is recorded as Ke, and the maximum allowable operating voltage of the power device of the motor controller is recorded as Ub.

[0012] Among them, using permanent magnets containing cerium as magnetic poles can reduce the content of praseodymium and neodymium elements in the permanent magnets, thereby reducing the production cost of the permanent magnets and further reducing the production cost of the motors, solving the problem in related technologies of high motor costs caused by the high prices of rare earth materials such as praseodymium and neodymium.

[0013] Replacing the relatively expensive praseodymium and neodymium elements in permanent magnets with the abundant and relatively inexpensive cerium can effectively reduce the price of permanent magnets and improve the motor's cost-effectiveness. However, the introduction of cerium will somewhat reduce the coercive force of the permanent magnets, thereby reducing the magnetic energy product of the permanent magnets and weakening the rotor's magnetic properties. To ensure a constant air gap composite magnetic field, the stator magnetic field strength is often increased by increasing the number of stator windings. Furthermore, motor operation is typically regulated by a controller, and once the power device model is determined in the controller, the maximum operating voltage of the power device is also determined. Because the rotor magnetic field provided by the motor's permanent magnets is not adjustable, field weakening control is often required at high speeds to prevent the motor's load voltage from exceeding the allowable value of the power device. Simply increasing the stator magnetic field strength to compensate for the loss of the air gap composite magnetic field will increase the impact of the stator's armature reaction, which is detrimental to the motor's output power during high-speed field weakening, thereby limiting the compressor's operating range. This requires a matching and balanced design of the stator and rotor magnetic fields of the motor, and reasonable adjustment of the material usage of the motor's permanent magnets, windings, etc., so that the motor's back EMF design value meets the motor's weak magnetic overload capacity under the constraint of the power device's maximum operating voltage, thereby improving the motor's cost-effectiveness.

[0014] It is understandable 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. The impact of the armature reaction can be reduced in two ways. First, weaken the stator magnetic field. Second, enhance the rotor magnetic field. The stator magnetic field is related to the parameters of the windings wound around the stator teeth of the stator core. The rotor magnetic field is related to the parameters of the permanent magnets. Therefore, by optimizing the relationship between the weight Mp of multiple permanent magnets and the weight Mc of the windings, the air gap composite magnetic field can be kept in a balanced state. In this way, the output capacity of the motor at high speed and weak magnetic field can be improved, which is conducive to reducing the armature reaction.

[0015] It's understandable that permanent magnets contain cerium, and the amount of cerium used can affect the rotor's magnetic field. If the cerium content in the permanent magnets is too high, it can negatively impact the rotor's magnetic field and exacerbate armature reaction. If the cerium content is too low, the rotor's production cost remains high.

[0016] It is understood that the motor's back EMF value Ke at 1000 rpm is correlated with the maximum allowable operating voltage Ub of the motor controller's power devices. If the motor's back EMF value Ke at 1000 rpm is too high, the power devices may break down. If the motor's back EMF value Ke at 1000 rpm is too low, the motor's performance may not be fully utilized.

[0017] Therefore, by rationally setting the relationship between the mass percentage (X%) of cerium in each permanent magnet, the weight (Mp) of the multiple permanent magnets, the weight (Mc) of the windings, the maximum allowable operating voltage (Ub) of the motor controller's power devices, and the motor's back EMF (Ke) at 1000 rpm, such that (Mp / Mc) × Ub × X% ≤ Ke, the motor's cost-effectiveness can be improved while reducing the impact of armature reaction under load. This helps enhance the motor's load capacity under high-speed, field-weakening conditions and reduces production costs. This allows the use of permanent magnets with a higher cerium content to reduce the praseodymium and neodymium content in the permanent magnets, achieving even greater cost reduction and efficiency gains.

[0018] The motor described above in this application may also have the following additional technical features:

[0019] In the above technical solution, further, Mp, Mc, Ub and X% satisfy: 0.14×Ke≤(Mp / Mc)×Ub×X%≤0.69×Ke.

[0020] This technical solution further defines the relationship between the mass percentage (X%) of cerium in each permanent magnet, the weight (Mp) of the multiple permanent magnets, the weight (Mc) of the windings, the maximum allowable operating voltage (Ub) of the motor controller's power components, and the motor's back EMF (Ke) at 1000 rpm, so that the following conditions are met: 0.14 × Ke ≤ (Mp / Mc) × Ub × X% ≤ 0.69 × Ke. This improves the motor's cost-effectiveness while reducing the impact of armature reaction under load and enhancing the motor's load capacity during high-speed field-weakening operation.

[0021] 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.

[0022] This technical solution further defines the coordination structure of the rotor core and permanent magnets, ensuring that the rotor core weight, Mr, and the weight of the multiple permanent magnets, Mp, satisfy the following relationship: 0.17 ≤ Mp / Mr ≤ 0.26. This ensures that the rotor's permanent magnet magnetic field strength remains within a reasonable range, which helps improve the motor's torque output capability.

[0023] 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.

[0024] In this technical solution, the structure of the rotor core is further defined, so that the rotor core is further provided with a plurality of slot groups, which are arranged at intervals around the axis of the rotor core. A slot group is arranged between each magnet slot group and the outer peripheral wall of the rotor core.

[0025] The slit group includes an odd number of slits.

[0026] The motor is applied to a compressor. Since the compressor is a pulsating load, the rotor structure is reasonably set so that the slot group on the rotor core includes an odd number of slots.

[0027] In this way, the radial force density of the motor can be effectively improved, the noise and vibration level of the motor can be improved, and then the noise and vibration of the compressor can be improved.

[0028] 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.

[0029] In this technical solution, the structure of the rotor core is further refined so that the rotor core has multiple magnetic pole center lines. For example, the line connecting the center of the magnet slot group and the center of the axial hole of the rotor core constitutes the magnetic pole center line, which is referred to as the d-axis.

[0030] By reasonably setting the matching structure of the odd number of slits in the slit group and the magnetic pole center line, a part of the slits in the slit group are located on the first side of the magnetic pole center line, and the other part of the slits in the slit group are located on the second side of the magnetic pole center line. In other words, the arrangement positions of the odd number of slits in the slit group relative to the magnetic pole center line are divided. Since the number of slits in each slit group is odd, and the odd number of slits are distributed on opposite sides of the magnetic pole center line (that is, the first side of the magnetic pole center line and the second side of the magnetic pole center line), then, an even number of slits are arranged on the first side of the magnetic pole center line, and an odd number of slits are arranged on the second side of the magnetic pole center line, or an odd number of slits are arranged on the first side of the magnetic pole center line, and an even number of slits are arranged on the second side of the magnetic pole center line. In other words, the odd number of slits in the slit group are asymmetrically arranged along the magnetic pole center line.

[0031] Optionally, the number of slit groups is an even number, the number of magnet slot groups is an even number, the number of slit groups matches the number of magnet slot groups, and each magnet slot group is associated with a slit group. The line containing the magnetic pole centerline is associated with two slit groups, which are designated as the first slit group and the second slit group, respectively. The axis of the rotor core is located between the first slit group and the second slit group. After the first slit group rotates 180° in the direction of the rotor's rotation, the slits of the first slit group and the slits of the second slit group overlap. Similarly, after the second slit group rotates 180° in the direction of the rotor's rotation, the slits of the second slit group overlap with the slits of the first slit group.

[0032] This arrangement prevents the rotor's center of mass from deviating from the axis of rotation during rotation, maintaining the motor's dynamic balance. This prevents localized wear. Taking a 12-slot, 8-pole motor as an example, the odd-numbered slots in the slot group are asymmetrically arranged along the magnetic pole centerline. This reduces the radial force density at the 4th-order, 16th-order mechanical frequency by 53%, and reduces the noise level of the compressor in this frequency band by 5dB, resulting in significant noise reduction.

[0033] 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.

[0034] In this technical solution, the structure of the rotor core is further defined.

[0035] Specifically, the slit group includes two first slits, which are symmetrically arranged about the magnetic pole centerline. Each first slit includes a first end and a second end. The first ends of the two first slits are adjacent to each other, while the second ends of the two first slits are spaced apart from each other, with the second ends located between the first ends and the magnet slot group. In other words, the two first slits are configured in an "eight" shape. The angle formed between the two first slits is denoted as α, which is an acute angle.

[0036] Specifically, the magnet slot assembly includes two slot bodies, each of which includes a third end and a fourth end. The third ends of the two slot bodies are spaced apart from each other, while the fourth ends of the two slot bodies are adjacent to each other, with the fourth ends located between the third ends and the axis of the rotor core. In other words, the two slot bodies are configured in a V-shape. The angle formed between the first slit and the slot body, located on the same side of the magnetic pole centerline, is denoted as β, and is an acute angle.

[0037] The stator teeth consist of a tooth body and a tooth shoe. The tooth body extends radially along the rotor core. The tooth shoe is connected to the tooth body and is located at the circumferential end face of the tooth body. The width of the tooth body along the circumference of the rotor core is Bt.

[0038] The width of the permanent magnet along the circumference of the rotor core is recorded as H.

[0039] By properly setting the angle α between the two first slits, the angle β between the first slit on the same side of the magnetic pole centerline and the slot body, and the circumferential width H of the permanent magnet and the circumferential width Bt of the tooth body, the relationship is such that: H < α / β × Bt ≤ 3.4 mm, and 1.5 mm ≤ H ≤ 2 mm. This setting can reduce the motor's no-load cogging torque and load torque pulsation. It also ensures that the magnetic field in the stator core does not oversaturate, which helps improve the motor's output capacity.

[0040] In any of the above technical solutions, further, the slit group also 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.

[0041] In this technical solution, the slit group includes two first and second slits. One of the first and second slits is located on the first side of the magnetic pole centerline, and the first and second slits located on the first side of the magnetic pole centerline are arranged in parallel. The other first slit is located on the second side of the magnetic pole centerline. The two first slits are symmetrically arranged with the magnetic pole centerline as the axis of symmetry.

[0042] That is to say, the number of slits located on the first side of the magnetic pole centerline is greater than the number of slits located on the second side of the magnetic pole centerline. This setting can ensure that the waveform of the motor's air gap magnetic density under load conditions is close to a sine wave, thereby reducing the torque pulsation during the operation of the motor. It also improves the vibration noise during the operation of the motor. At the same time, this setting can ensure the dynamic balance of the rotor during rotation, reduce the swing of the compressor's shaft structure, and effectively improve the content of each harmonic of the motor's air gap magnetic density. In this way, on the one hand, the stator iron loss of the motor is reduced, which is conducive to improving the operating efficiency of the motor. On the other hand, it can improve the vibration noise of the motor, thereby reducing the operating noise of the compressor.

[0043] 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.

[0044] This technical solution further defines the coordination structure of the two first slits and the second slit, such that the two first slits are located immediately adjacent to the magnetic pole centerline, and the second slit is located on the side of the first slits that is further from the magnetic pole centerline. In other words, the second slit is located outside the first slit. In other words, the first slit is closer to the magnetic pole centerline than the second slit.

[0045] The compressor load is not constant but rather fluctuates periodically. Positioning the second slit outside the first slit helps ensure a near-sinusoidal waveform in the motor's air gap flux density under load conditions, thereby reducing torque ripple and improving vibration and noise during motor operation. Furthermore, the asymmetric structure ensures dynamic balance during rotor rotation, reduces vibration in the compressor shafting, and effectively improves the harmonic content of the motor's air gap flux density.

[0046] 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.

[0047] This technical solution further defines the relationship between the rotor's rotational direction and the first and second sides of the magnetic pole centerline. Specifically, the rotor rotates from the second side of the magnetic pole centerline toward the first side of the magnetic pole centerline. Alternatively, the first side of the magnetic pole centerline is considered the windward side, and the second side of the magnetic pole centerline is considered the leeward side.

[0048] That is, one first slit and one second slit are located on the windward side of the magnetic pole centerline, and the other first slit is located on the leeward side of the magnetic pole centerline. In other words, one first slit and one second slit are arranged at the magnetic pole portion position in the same direction as the rotor rotation direction.

[0049] This setting is beneficial to reducing the no-load cogging torque and load electromagnetic torque pulsation of the motor.

[0050] In any of the above technical solutions, further, the mass percentage of cerium in the permanent magnet satisfies: 2%<X%<6%.

[0051] In this technical solution, the range of the mass percentage of cerium in the permanent magnet is further limited so that the mass percentage of cerium in the permanent magnet satisfies: 2%<X%<6%. This setting takes into account both the performance and production cost of the motor.

[0052] In other words, adding the inexpensive and abundant element cerium to permanent magnets can reduce the use of expensive and scarce heavy rare earth elements, thereby lowering motor production costs. In other words, while maintaining motor performance, the cost of permanent magnets can be reduced, improving the motor's cost-effectiveness.

[0053] If the mass percentage of cerium in the permanent magnet is greater than or equal to 6%, the coercive force of the permanent magnet will decrease, which will reduce the magnetic energy product of the permanent magnet and weaken the magnetic properties of the rotor, which will in turn affect the motor's anti-demagnetization ability and motor efficiency, causing demagnetization of the rotor during operation, reducing the reliability and stability of the motor.

[0054] If the mass percentage of cerium in the permanent magnet 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.

[0055] Specifically, the mass percentage of cerium in the permanent magnet includes 2.5%, 3%, 3.5%, 4%, 4.5%, 5% and 5.5%, etc., which are not listed here one by one.

[0056] In any of the above technical solutions, further, the maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

[0057] In this technical solution, the value of the maximum allowable operating voltage of the power device of the motor controller is further limited.

[0058] Optionally, the maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

[0059] The power devices of the motor controller include, but are not limited to, SiC (silicon carbide) power devices, IGBT (Insulated Gate Bipolar Transistor) and GaN (gallium nitride) power devices.

[0060] The maximum allowable operating voltage of the controller's power device is equal to 650V, or the maximum allowable operating voltage of the controller's power device is equal to 1200V. In this case, the efficiency of the motor controller is higher. 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 or 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 or 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.

[0061] 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.

[0062] In this technical solution, the structure of the permanent magnet is further defined so that the residual magnetic flux density of the permanent magnet at 20°C is recorded as Br, Br is greater than or equal to 1.2T, and Br is less than or equal to 1.5T. This setting can ensure that the magnetic field strength of the rotor is within a reasonable range. Since the magnetic field of the rotor is not adjustable, if the residual magnetic flux density Br of the permanent magnet at 20°C is greater than 1.5T, it will limit the high-speed weak magnetic operation of the motor. If the residual magnetic flux density Br of the permanent magnet at 20°C is less than 1.2T, the motor will not be able to provide sufficient output capacity.

[0063] 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.

[0064] This technical solution further defines the structure of the permanent magnet, ensuring that its intrinsic coercivity (Hcj) at 20°C is greater than or equal to 21.3 kOe and less than or equal to 25.2 kOe. The intrinsic coercivity of a permanent magnet is a key indicator of its resistance to demagnetization. If Hcj is less than 21.3 kOe, the magnet's resistance to demagnetization is weak, and irreversible demagnetization may occur during motor operation. If Hcj is greater than 25.2 kOe, the use of heavy rare earth elements increases, dramatically increasing costs and hindering the motor's cost-effectiveness.

[0065] A second aspect of the present invention provides a compressor, comprising: a motor as in any technical solution of the first aspect.

[0066] The compressor provided by the present invention includes a motor as in any technical solution in the first aspect, and therefore has all the beneficial effects of the above-mentioned motors, which will not be described one by one here.

[0067] A third aspect of the present invention provides a vehicle, comprising: the compressor according to the second aspect.

[0068] The vehicle provided by the present invention includes the compressor as in the second aspect, and therefore has all the beneficial effects of the above-mentioned compressor, which will not be described one by one here.

[0069] 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.

[0070] 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

[0071] 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:

[0072] Figure 1 A partial structural schematic diagram of a motor according to an embodiment of the present application is shown;

[0073] Figure 2 A partial structural schematic diagram of a rotor according to an embodiment of the present application is shown;

[0074] Figure 3 A maximum torque variation curve diagram of a motor according to an embodiment of the present application is shown;

[0075] Figure 4 A schematic diagram comparing the no-load cogging torque of the motors in the present application and related technologies is shown;

[0076] Figure 5 A load torque pulsation variation curve diagram of a motor according to an embodiment of the present application is shown;

[0077] Figure 6 A curve diagram of stator and rotor flux variation of a motor according to an embodiment of the present application is shown.

[0078] in, Figure 1 and Figure 2 The corresponding relationship between the reference numerals and component names is as follows:

[0079] 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. DETAILED DESCRIPTION

[0080] 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.

[0081] 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.

[0082] Refer to the following Figures 1 to 6 A motor 10 , a compressor, and a vehicle according to some embodiments of the present application.

[0083] like Figure 1 and Figure 2 As shown, a motor 10 according to some embodiments of the present application includes a rotor 100 and a stator 200 .

[0084] The rotor 100 includes a rotor core 110 and a plurality of permanent magnets 120 .

[0085] 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 .

[0086] A permanent magnet 120 is disposed in each magnet slot group 130 .

[0087] The permanent magnet 120 contains X mass % of cerium.

[0088] The stator 200 includes a stator core 210 and a winding 220 .

[0089] The stator core 210 includes a plurality of stator teeth 212 , which are spaced apart around the axis of the stator core 210 .

[0090] The plurality of stator teeth 212 enclose a mounting cavity 214 , and the rotor 100 is rotatably disposed in the mounting cavity 214 .

[0091] The winding 220 is wound around the plurality of stator teeth 212 .

[0092] The weight of the plurality of permanent magnets 120 is denoted as Mp.

[0093] The weight of the winding 220 is denoted as Mc.

[0094] The back electromotive force value of the motor 10 at a rotation speed of 1000 rpm is recorded as Ke.

[0095] The maximum allowable operating voltage of the power devices of the controller of the motor 10 is denoted as Ub.

[0096] Among them, (Mp / Mc)×Ub×X%≤Ke.

[0097] In this embodiment, the motor 10 includes a rotor 100 and a stator 200 .

[0098] 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.

[0099] 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 .

[0100] 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.

[0101] 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.

[0102] 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 stator 200 magnetic field strength to compensate for the loss of the air gap composite magnetic field will exacerbate the armature reaction of the stator 200, hindering the output capacity of the 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 100 magnetic fields of the motor 10, and appropriate adjustment of the material usage of the motor 10's permanent magnets 120, windings 220, and other components. This ensures that the motor 10's back EMF design value meets the motor 10's field weakening overload capacity within the constraints of the power device's maximum operating voltage, thereby improving the motor 10's cost-effectiveness.

[0103] 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.

[0104] 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.

[0105] 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.

[0106] Therefore, by rationally setting the relationship between the mass percentage X% of cerium in each permanent magnet 120, the weight Mp of the plurality of 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 as to satisfy the following equation: (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, thereby enhancing the load capacity of the motor 10 under high-speed, field-weakening conditions and reducing the production cost of the motor 10. Thus, 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.

[0107] Specifically, 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.

[0108] In some embodiments, Mp, Mc, Ub, and X% satisfy: 0.14×Ke≤(Mp / Mc)×Ub×X%≤0.69×Ke.

[0109] In this embodiment, the relationship between the mass percentage (X%) of cerium in each permanent magnet 120, the weight (Mp) of the plurality of 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 (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, thereby enhancing the motor's load capacity during high-speed field-weakening operation.

[0110] The armature reaction can be measured by the maximum torque of the motor 10, Figure 3 The maximum torque curve of the motor 10 is given by Figure 3 It can be seen that when the above relationship among 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.

[0111] Specifically, (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.

[0112] In some embodiments, the weight of the rotor core 110 is denoted as Mr, where 0.17≤Mp / Mr≤0.26.

[0113] 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.

[0114] Figure 6This is a graph of the rotor 100 flux and the stator 200 armature flux of motor 10 at maximum load. The difference between the rotor 100 flux and the stator 200 armature flux can quantitatively describe the degree of load-armature reaction of motor 10. A strong armature magnetic field will lead to a deeper field weakening depth at high speed of motor 10, resulting in a sharp drop in torque output. A strong permanent magnet magnetic 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 multiple permanent magnets 120, the absolute value of the difference between the rotor 100 flux and the stator 200 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 speed of motor 10 and can improve the output capacity of high-speed field weakening of motor 10.

[0115] Specifically, the ratios of the weight Mp of the plurality of permanent magnets 120 to the weight Mr of the rotor core 110 include: 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.

[0116] In some embodiments, as Figure 1 and Figure 2 As shown, the rotor core 110 is further provided with a plurality of slot groups 140 .

[0117] 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 .

[0118] 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.

[0119] The slit group 140 includes an odd number of slits 142 .

[0120] 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 .

[0121] 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.

[0122] In some embodiments, as Figure 1 and Figure 2 As shown, 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 .

[0123] A portion of the slots 142 of the slot group 140 is located on a first side of the magnetic pole centerline 150 .

[0124] Another portion of the slots 142 of the slot group 140 is located on a second side of the magnetic pole centerline 150 .

[0125] 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.

[0126] 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.

[0127] Optionally, 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 cooperating with one slot group 140. The line on which the magnetic pole centerline 150 lies is aligned with 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.

[0128] Figure 2 The arrow in indicates the rotation direction of the rotor 100 .

[0129] This arrangement prevents the center of mass of the rotor 100 from deviating from the axis of rotation during rotation, maintaining the dynamic balance of the motor 10. Local wear and tear will not occur. Taking a 12-slot, 8-pole motor 10 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, resulting in a significant noise improvement effect.

[0130] In some embodiments, the slit group 140 includes two first slits 144 .

[0131] The two first slits 144 are symmetrically arranged with the magnetic pole center line 150 as a symmetry axis.

[0132] The first slit 144 includes a first end 1442 and a second end 1444 .

[0133] 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.

[0134] The second end portion 1444 is located between the first end portion 1442 and the magnet slot set 130 .

[0135] The angle formed between the two first slits 144 is denoted as α.

[0136] The magnet slot set 130 includes two slot bodies 132 .

[0137] The slot body 132 includes a third end 1322 and a fourth end 1324 .

[0138] 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.

[0139] The fourth end portion 1324 is located between the third end portion 1322 and the axis of the rotor core 110 .

[0140] 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.

[0141] The stator tooth 212 includes a tooth body 2122 and a tooth shoe 2124 .

[0142] The tooth shoe 2124 is connected to the circumferential end surface of the tooth body 2122 .

[0143] The circumferential width of the tooth body 2122 is denoted as Bt.

[0144] The circumferential width of the permanent magnet 120 is denoted by H.

[0145] Among them, H<α / β×Bt≤3.4mm, 1.5mm≤H≤2mm.

[0146] In this embodiment, the structure of the rotor core 110 is further defined.

[0147] Specifically, 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.

[0148] Specifically, the magnet slot group 130 includes two slot bodies 132, and each 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, 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 to form a "V"-shaped structure. 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, and the angle β is an acute angle. As Figure 2 As shown, the circumferential end surface of the first slit 144 facing the magnetic pole center line 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 recorded as β.

[0149] like Figure 1 As shown, the stator tooth 212 includes a tooth body 2122 and a tooth shoe 2124. The tooth body 2122 extends in the radial direction of 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 width of the tooth body 2122 is Bt.

[0150] like Figure 2 As shown, the width of the permanent magnet 120 along the circumferential direction of the rotor core 110 is denoted as H.

[0151] 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.

[0152] Figure 4 The figure is a numerical comparison of the cogging torque of the 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 a plurality of slit groups 140, and the odd number of slits 142 of each slit group 140 are asymmetrically arranged along the magnetic pole center line 150, the no-load cogging torque is 0.21Nm, and 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 in the related art, and the cogging torque reduction effect is obvious.

[0153] In some embodiments, as Figure 1 and Figure 2 As shown, the slit set 140 further includes a second slit 146 .

[0154] 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 .

[0155] 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.

[0156] 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.

[0157] In some embodiments, as Figure 1 and Figure 2 As shown, the two first slots 144 are disposed proximate to the magnetic pole centerline 150 .

[0158] The second slit 146 is located on a side of the first slit 144 away from the magnetic pole centerline 150 .

[0159] 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.

[0160] 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.

[0161] In some embodiments, as Figure 2 As shown, 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 .

[0162] In this embodiment, the relationship between the rotation direction of rotor 100 and the first and second sides of magnetic pole centerline 150 is further defined. Specifically, rotor 100 rotates from the second side of magnetic pole centerline 150 toward the first side of magnetic pole centerline 150. It can also be understood that the first side of magnetic pole centerline 150 is the windward side, and the second side of magnetic pole centerline 150 is the leeward side.

[0163] 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.

[0164] This arrangement is beneficial for reducing the no-load cogging torque and load electromagnetic torque pulsation of the motor 10 .

[0165] In some embodiments, the mass percentage of cerium in the permanent magnet 120 satisfies: 2%<X%<6%.

[0166] 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.

[0167] 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.

[0168] 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.

[0169] 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.

[0170] Specifically, 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.

[0171] In some embodiments, the maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

[0172] 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.

[0173] Optionally, the maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

[0174] 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.

[0175] 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.

[0176] In some embodiments, the residual magnetic flux density Br of the permanent magnet 120 at 20° C. satisfies: 1.2T≤Br≤1.5T.

[0177] 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.

[0178] Optionally, the values of the residual magnetic flux density Br of the permanent magnet 120 at 20° C. include: 1.25T, 1.3T, 1.34T, 1.4T, 1.46T, etc., which are not listed here one by one.

[0179] In some embodiments, the intrinsic coercivity Hcj of the permanent magnet 120 at 20° C. satisfies: 21.3 kOe≤Hcj≤25.2 kOe.

[0180] 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.

[0181] According to some further embodiments of the present application, a compressor includes: a motor 10 as described in any of the above embodiments.

[0182] In this embodiment, the compressor includes a motor 10 .

[0183] The motor 10 includes a rotor 100 and a stator 200 .

[0184] 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.

[0185] 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 .

[0186] 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.

[0187] 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.

[0188] 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 stator 200 magnetic field strength to compensate for the loss of the air gap composite magnetic field will exacerbate the armature reaction of the stator 200, hindering the output capacity of the 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 100 magnetic fields of the motor 10, and appropriate adjustment of the material usage of the motor 10's permanent magnets 120, windings 220, and other components. This ensures that the motor 10's back EMF design value meets the motor 10's field weakening overload capacity within the constraints of the power device's maximum operating voltage, thereby improving the motor 10's cost-effectiveness.

[0189] 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.

[0190] 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.

[0191] 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.

[0192] Therefore, by rationally setting the relationship between the mass percentage X% of cerium in each permanent magnet 120, the weight Mp of the plurality of 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 as to satisfy the following equation: (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, thereby enhancing the load capacity of the motor 10 under high-speed, field-weakening conditions and reducing the production cost of the motor 10. Thus, 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.

[0193] According to some further embodiments of the present application, a vehicle includes: a compressor as described in the above embodiments.

[0194] In this embodiment, the vehicle includes a compressor.

[0195] The compressor includes a motor 10 .

[0196] The motor 10 includes a rotor 100 and a stator 200 .

[0197] 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.

[0198] 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 .

[0199] 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.

[0200] 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.

[0201] 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 stator 200 magnetic field strength to compensate for the loss of the air gap composite magnetic field will exacerbate the armature reaction of the stator 200, hindering the output capacity of the 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 100 magnetic fields of the motor 10, and appropriate adjustment of the material usage of the motor 10's permanent magnets 120, windings 220, and other components. This ensures that the motor 10's back EMF design value meets the motor 10's field weakening overload capacity within the constraints of the power device's maximum operating voltage, thereby improving the motor 10's cost-effectiveness.

[0202] 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.

[0203] 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.

[0204] 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.

[0205] Therefore, by rationally setting the relationship between the mass percentage X% of cerium in each permanent magnet 120, the weight Mp of the plurality of 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 as to satisfy the following equation: (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, thereby enhancing the load capacity of the motor 10 under high-speed, field-weakening conditions and reducing the production cost of the motor 10. Thus, 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.

[0206] 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.

[0207] 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. Permanent magnets 120 contain X% by mass of cerium (Ce). Slot groups 140 are arranged in the magnetic pole portion formed between the outer peripheral 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.

[0208] 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.

[0209] 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.

[0210] 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.

[0211] 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.

[0212] Among them, H<α / β×Bt≤3.4mm, 1.5mm≤H≤2mm.

[0213] The weight of the rotor core 110 is denoted as Mr, where 0.17≤Mp / Mr≤0.26.

[0214] The mass percentage of cerium in the permanent magnet 120 satisfies: 2%<X%<6%.

[0215] 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.

[0216] 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.

[0217] 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.

[0218] The residual magnetic flux density Br of the permanent magnet 120 at 20° C. satisfies: 1.2T≤Br≤1.5T.

[0219] The intrinsic coercive force Hcj of the permanent magnet 120 at 20° C. satisfies: 21.3 kOe≤Hcj≤25.2 kOe.

[0220] 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.

[0221] 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.

[0222] 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.

[0223] 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.

[0224] 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.

[0225] 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.

[0226] 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.

[0227] 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.

[0228] The load capacity of the motor 10 at high speed and weak magnetic field can be represented by the output torque of the motor 10. A 12-slot 8-pole motor 10 is used as an example for simulation. The torque of the motor 10 at the maximum current and highest speed of the motor 10 under weak magnetic field conditions is calculated. Figure 3This is a graph 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, motor 10 has a high torque output capacity and meets product requirements. At this point, motor 10 has a weak armature reaction under high-speed, field-weakening conditions, and strong load capacity. The dotted line in the graph represents product usage requirements.

[0229] Figure 4 The following is a comparison chart of the cogging torque values of a motor of the related art (the motor does not have 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, the no-load cogging torque of the present application 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 of the present application is only 21.4% of the cogging torque of the motor of the related art, and the cogging torque is significantly reduced.

[0230] Figure 5 This 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.

[0231] Figure 6 This graph shows the rotor 100 flux linkage and the stator 200 armature flux linkage of motor 10 at maximum load. The difference between the rotor 100 flux linkage and the stator 200 armature flux linkage 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 100 flux linkage and the stator 200 armature flux linkage 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.

[0232] 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.

[0233] Optionally, the stator core 210 includes: a first punching group; a second punching group, wherein the second punching group is stacked on one side of the first punching group along the axial direction of the stator core 210 and is 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, and 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, wherein 1<d2 / d1<3. Each stator tooth 212 includes one tooth of the first punching group and one tooth of the second punching group.

[0234] The first punching sheet group and the second punching sheet group are arranged along the axial direction of the stator core 210 . Specifically, 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.

[0235] 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.

[0236] 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.

[0237] 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.

[0238] 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.

[0239] 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.

[0240] 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 be separated from the teeth, which makes it impossible to ensure the stability and reliability of the electron movement. This setting also increases the gap between the stator and rotor 100 of the motor 10, affecting the power density of the motor 10 and the torque output of the motor 10.

[0241] 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.

[0242] Optionally, 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.

[0243] Optionally, the number of first punching sheet groups is recorded as m, the number of second punching sheet groups is recorded as n, and a first punching sheet group is provided between any two adjacent second punching sheet groups; wherein m≥1, n≥2.

[0244] 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.

[0245] 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.

[0246] 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.

[0247] Optionally, 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.

[0248] The structures of the first and second punching sheet groups are further defined so that along the axial direction of the stator core 210, the height of the first punching sheet group is recorded as h1, and the height of the second punching sheet group is recorded 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 the first punching sheet groups included in the stator core 210 and the sum of the axial heights of all the second punching sheet groups included in the stator core 210 is defined. Because reducing the slot width of the second punching sheet group in the circumferential direction of the stator core 210 will increase the risk of magnetic leakage of the stator 200, by defining the optimal ratio of the axial heights of the first and second punching sheet groups, the risk of magnetic leakage can be minimized to the maximum extent, that is, the magnetic leakage can be reduced while ensuring the performance of the motor 10.

[0249] Optionally, 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.

[0250] 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.

[0251] 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.

[0252] 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 between 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.

[0253] 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.

[0254] 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.

[0255] Optionally, along the axial direction of the stator core 210 , the orthographic projection of the stator slot wall of the third punching sheet group on the second punching sheet group is located outside the stator slot wall of the second punching sheet group.

[0256] 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.

[0257] Specifically, the stator 200 also includes an insulating bracket. When the stator core 210 is mated and connected to the insulating bracket, an insulating protrusion is provided on the insulating bracket. The insulating protrusion abuts within the recessed groove and can cover the edge of the stator slot of the third punching group. In this way, while ensuring the performance of the motor 10, the height of the stator 200 can be reduced along the axial direction of the stator core 210, which helps reduce the internal space occupied by the stator 200 of the motor 10, thereby reducing the volume and weight of the motor 10.

[0258] 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 .

[0259] 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.

[0260] Optionally, 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.

[0261] The wall surface of the tooth portion facing the axis of the stator core 210 is the tooth surface.

[0262] The structures of the first punching sheet group, the second punching sheet group and the third punching sheet group are further defined.

[0263] Specifically, 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.

[0264] 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.

[0265] 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.

[0266] Optionally, 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.

[0267] 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.

[0268] 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.

[0269] 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.

[0270] Optionally, along the radial direction of the rotor 100 , a value of the minimum gap between the outer circumferential wall of the rotor 100 and the inner circumferential wall of the stator 200 is recorded as δ, wherein 0.08<δ / d2<0.15.

[0271] By optimizing the ratio of the slot width of the second punching sheet group to the gap between the stator and rotor 100, 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.

[0272] 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.

[0273] 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.

[0274] Optionally, 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.

[0275] 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.

[0276] 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.

[0277] 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.

[0278] 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.

[0279] 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.

[0280] 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.

[0281] Optionally, the extension is connected to the slot wall of the stator slot. The matching 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.

[0282] Optionally, the insulating tooth 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, and the two extension sections 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.

[0283] 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.

[0284] 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.

[0285] 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.

[0286] Optionally, 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.

[0287] 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.

[0288] 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.

[0289] Optionally, 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.

[0290] 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.

[0291] 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.

[0292] Optionally, 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.

[0293] 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.

[0294] 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.

[0295] Optionally, 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.

[0296] 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.

[0297] 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 be separated from the teeth, which makes it impossible to ensure the stability and reliability of the electron movement. This setting also increases the gap between the stator and rotor 100 of the motor 10, affecting the power density of the motor 10 and the torque output of the motor 10.

[0298] Optionally, 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 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.

[0299] 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.

[0300] 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.

[0301] 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 between 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.

[0302] 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.

[0303] 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.

[0304] Optionally, 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.

[0305] The structure of the rotor 100 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.

[0306] 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.

[0307] Specifically, the inter-pole centerline is also referred to as the adjacent magnetic pole centerline 150 , or q-axis for short.

[0308] Optionally, 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., which are not listed here one by one.

[0309] 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.

[0310] 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, characterized in that: 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 spaced apart around an 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, the stator comprising a stator core and a winding, the stator core comprising a plurality of stator teeth, the plurality of stator teeth being spaced apart and arranged around an 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 around the plurality of stator teeth; The weight of the multiple permanent magnets is recorded as Mp, the weight of the winding is recorded as Mc, the back electromotive force value of the motor 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 is recorded as Ub, wherein (Mp / Mc)×Ub×X%≤Ke.

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

26.

4. The motor according to claim 1 or 2, characterized in that The rotor core is further provided with a plurality of slot groups. One slot group is arranged between each magnet slot group and the outer peripheral wall of the rotor core. The slot group includes an odd number of slots.

5. The motor according to claim 4, characterized in that The rotor core has multiple 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, characterized in that The slit group includes two first slits, the two first slits are symmetrically arranged with the magnetic pole centerline 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 separated from each other, and the second end is located between the first end and the magnet slot group, and the angle formed between the two first slits is denoted as α; The magnet slot group includes two slot bodies, each of which includes a third end and a fourth end. The third ends of the two slot bodies are far away from each other, and the fourth ends of the two slot bodies are closely adjacent to each other. 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 teeth include 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, characterized in that The slit group further includes a second slit, which is located on a first side of the magnetic pole centerline and is parallel to the first slit.

8. The motor according to claim 7, characterized in that 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 motor according to claim 5, characterized in that 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 motor according to claim 1 or 2, characterized in that The mass percentage of cerium in the permanent magnet satisfies: 2%<X%<6%.

11. The motor according to claim 1 or 2, characterized in that The residual magnetic flux density Br of the permanent magnet at 20° C. satisfies the following conditions: 1.2T≤Br≤1.5T; The maximum allowable operating voltage Ub=650V, or the maximum allowable operating voltage Ub=1200V.

12. The motor according to claim 1 or 2, characterized in that The intrinsic coercive force Hcj of the permanent magnet at 20° C. satisfies the following: 21.3 kOe≤Hcj≤25.2 kOe.

13. A compressor, characterized in that: include: A motor as claimed in any one of claims 1 to 12.

14. A vehicle, characterized in that: include: The compressor of claim 13.

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