Motor, compressor and refrigeration equipment

Abstract

The utility model provides a motor, a compressor and refrigeration equipment. The motor comprises a stator and a rotor, the stator comprises a stator core, the stator core comprises a plurality of laminated stator punching sheets, each stator punching sheet comprises a stator yoke part and stator teeth arranged in the circumferential direction of the inner circle of the stator yoke part, a stator groove is formed between every two adjacent stator teeth, and the rotor comprises a rotor core and a plurality of permanent magnets. The rotor core is provided with a plurality of magnet grooves, and the permanent magnets are arranged in the magnet grooves; the number of the stator grooves is Q, the outer diameter of the stator punching sheet is D, the shortest width of the stator teeth is Wt, the cross sectional area of the permanent magnet perpendicular to the axial direction of the motor is S, the saturation magnetic density of the stator punching sheet is Bm, the residual magnetism of the permanent magnet is Br, and Q * Wt * D * Bm / (S * Br) is larger than or equal to 30 and smaller than or equal to 140. According to the utility model, the evaluation coefficient K is formed by the parameters related to the efficiency of the motor, and the motor in the value range of the evaluation coefficient K has the advantages of high efficiency and low cost.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, specifically to a motor, a compressor, and a refrigeration device. Background Technology

[0002] Compared to traditional asynchronous motors, permanent magnet synchronous motors use permanent magnets for excitation, resulting in a simpler structure, higher energy efficiency, lower noise, and smoother operation. They offer advantages such as high efficiency and power density, and are widely used in aerospace, electric vehicles, rail transportation, and variable frequency air conditioning technologies. To reduce eddy current losses, the rotor structure of existing permanent magnet synchronous motors is mostly made of laminated permanent magnet motor laminations, with permanent magnet material mounted on the laminations.

[0003] Permanent magnets contain many rare earth elements, such as dysprosium and neodymium, which are important strategic energy sources. To protect the environment and conserve energy, it is necessary to further improve the efficiency of compressor motors and the utilization rate of rare earth materials. Utility Model Content

[0004] To address the problems in the existing technology, the purpose of this utility model is to provide a motor, compressor, and refrigeration equipment that improves motor efficiency and reduces motor cost while limiting the amount of permanent magnets used.

[0005] This utility model embodiment provides a motor, including:

[0006] A stator includes a stator core, the stator core comprising a plurality of stacked stator laminations, each stator lamination comprising a stator yoke and stator teeth circumferentially arranged along the inner circle of the stator yoke, with stator slots formed between adjacent stator teeth.

[0007] The rotor includes a rotor core and a plurality of permanent magnets. The rotor core is provided with a plurality of magnet slots, and the permanent magnets are disposed in the magnet slots.

[0008] The number of stator slots is Q, the outer diameter of the stator lamination is D, the shortest width of the stator tooth is Wt, the cross-sectional area of ​​the permanent magnet perpendicular to the motor axis is S, the saturation magnetic density of the stator lamination is Bm, and the remanence of the permanent magnet is Br. Q, Wt, D, Bm, and Br satisfy the following relationship: 30≤Q*Wt*D*Bm / (S*Br)≤140.

[0009] In some embodiments, the number of stator slots is Q, the number of rotor poles is P, and Q and P satisfy: Q / P = 3:2.

[0010] In some embodiments, the stator laminations are silicon steel sheets.

[0011] In some embodiments, the saturation magnetic density Bm of the silicon steel sheet satisfies: 1.7T≤Bm≤2.5T.

[0012] In some embodiments, the Br satisfies 1.25T≤Br≤1.6T.

[0013] In some embodiments, S satisfies: 100mm 2 ≤S≤280mm 2 .

[0014] In some embodiments, D satisfies: 80mm≤D≤120mm.

[0015] In some embodiments, the width of the stator tooth on the side near the stator yoke is Wt, which satisfies 3mm≤Wt≤10mm.

[0016] This utility model embodiment also provides a compressor, including the motor described above.

[0017] This utility model embodiment also provides a refrigeration device, including the compressor described above.

[0018] The motor, compressor, and refrigeration equipment provided by this utility model have the following advantages:

[0019] This invention establishes an evaluation coefficient K based on parameters related to motor efficiency. The evaluation coefficient K can limit the minimum amount of permanent magnets used to ensure motor efficiency, and can also limit the maximum amount of permanent magnets used to ensure the material utilization rate of rare earth materials, thereby reducing motor costs. Motors that meet the value range of the evaluation coefficient K can achieve both high efficiency and low cost. Attached Figure Description

[0020] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0021] Figure 1 This is a schematic diagram of the end face of a motor according to an embodiment of the present invention.

[0022] Figure label:

[0023] 100 stator laminations

[0024] 10 Stator yoke part

[0025] 20 stator teeth

[0026] 21 stator slots

[0027] 30 permanent magnets Detailed Implementation

[0028] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that the invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0029] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics represented in connection with that embodiment or example, which are included in at least one embodiment or example of this application. Furthermore, the specific features, structures, materials, or characteristics represented may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate different embodiments or examples represented in this application, as well as features of different embodiments or examples.

[0030] It should be further understood that the terms "comprising" or "including" indicate the presence of a feature, step, operation, element, component, item, kind, and / or group, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms "or" and "and / or" as used herein are interpreted as inclusive, or mean any one or any combination thereof. Therefore, "A, B, or C" or "A, B, and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C." Exceptions to this definition only arise when a combination of elements, functions, steps, or operations is inherently mutually exclusive in some way.

[0031] To address the problems in the prior art, this utility model provides an electric motor, comprising: a stator, including a stator core, the stator core including a plurality of stacked stator laminations, each stator lamination including a stator yoke and stator teeth circumferentially arranged along the inner circle of the stator yoke, with stator slots formed between adjacent stator teeth; and a rotor, including a rotor core and a plurality of permanent magnets, the rotor core having a plurality of magnet slots, the permanent magnets being disposed in the magnet slots; the number of stator slots is Q, the outer diameter of the stator laminations is D, the shortest width of the stator teeth is Wt, the cross-sectional area of ​​the permanent magnet perpendicular to the motor axis is S, the saturation magnetic density of the stator laminations is Bm, and the remanence of the permanent magnet is Br. The relationships 30 ≤ K = Q * Wt * D * Bm / (S * Br) ≤ 140 are satisfied. This technical solution uses an evaluation coefficient K to define parameters related to motor efficiency. The evaluation coefficient K can limit the minimum amount of permanent magnets used to ensure motor efficiency, and can also limit the maximum amount of permanent magnets used to ensure the material utilization rate of rare earth materials, thereby reducing motor costs. Motors that meet the value range of the evaluation coefficient K can achieve both high efficiency and low cost.

[0032] The motor of this utility model will be further described below with reference to the accompanying drawings. It should be understood that the specific embodiments are not intended to limit the scope of protection of this utility model.

[0033] Figure 1 A schematic diagram of the end face of a motor according to an embodiment of the present invention is shown. Figure 1 As shown, the motor includes a stator and a rotor. The stator includes a stator core, which includes multiple stacked stator laminations. Each stator lamination includes a stator yoke 10 and stator teeth 20 arranged circumferentially along the inner circumference of the stator yoke 10. A stator slot 21 is formed between two adjacent stator teeth 20. The rotor includes a rotor core and multiple permanent magnets 30. The rotor core is provided with multiple magnet slots, and the permanent magnets 30 are disposed in the magnet slots.

[0034] The number of stator slots 21 is Q, the outer diameter of the stator lamination is D, the shortest width of the stator tooth 20 is Wt, the cross-sectional area of ​​the permanent magnet 30 perpendicular to the motor axis is S, the saturation magnetic density of the stator lamination is Bm, and the remanence of the permanent magnet 30 is Br, satisfying the relationship: 30≤Q*Wt*D*Bm / (S*Br)≤140.

[0035] Furthermore, in some embodiments, the number of stator slots is Q, and the number of rotor poles is P, wherein Q and P satisfy Q / P = 3:2. In this embodiment, the motor is a 10-pole, 15-slot motor. In another embodiment, the motor can also be an 8-pole, 12-slot motor, a 6-pole, 9-slot motor, or a 12-pole, 18-slot motor. Those skilled in the art can set the number of stator slots 21 and the number of rotor poles according to actual needs.

[0036] Furthermore, in some embodiments, the stator lamination 100 is made of silicon steel. Silicon steel lamination has low iron loss, high stacking factor, good magnetic induction intensity, and good lamination performance, thereby ensuring good working performance of the stator lamination; silicon steel lamination can reduce eddy current loss and hysteresis loss, thereby reducing core heating, and the silicon steel lamination is insulated from each other, which can reduce the current flow area and further reduce heating.

[0037] Furthermore, the saturation magnetic density Bm of the silicon steel sheet satisfies: 1.7T ≤ Bm ≤ 2.5T. Exemplary Bm values ​​can be 1.8T, 1.9T, 2.0T, 2.1T, 2.2T, 2.3T, and 2.4T. An increase in the magnetic saturation density Bm indicates that the silicon steel sheet of the motor is less likely to reach saturation, allowing for the use of more permanent magnets to improve motor efficiency with the same amount of silicon steel sheet. In a preferred embodiment, to improve motor efficiency and reduce motor cost, the magnetic saturation density Bm can satisfy: 1.8T ≤ Bm ≤ 2.0T.

[0038] Furthermore, in some embodiments, the remanence Br of the permanent magnet 30 satisfies 1.25T ≤ Br ≤ 1.6T. For example, Br can be 1.3T, 1.35T, 1.4T, 1.45T, 1.5T, and 1.55T. The cross-sectional area S of the permanent magnet 30 perpendicular to the motor axis satisfies: 100mm². 2 ≤S≤280mm 2 For example, S can be 110 mm. 2 130mm 2 150mm 2 170mm 2 190mm 2 210mm 2 230mm 2 250mm 2 270mm 2 Increasing Br and S provides more magnetomotive force to each stator tooth 20 of the motor, correspondingly increasing the motor's flux linkage. However, excessively high magnetomotive force can cause the magnetic field density of the silicon steel sheet to saturate, leading to a sharp increase in magnetic reluctance, a slowdown in the increase of flux linkage, and a sharp increase in the motor's iron losses. At this point, further increasing Br and S cannot improve motor efficiency and will increase motor costs. However, excessively low Br and S will reduce motor efficiency. To improve motor efficiency and reduce motor costs, in a preferred embodiment, Br satisfies 1.39T ≤ Br ≤ 1.5T.

[0039] Furthermore, in some embodiments, the diameter D of the stator lamination satisfies: 80mm ≤ D ≤ 120mm. For example, D can be 85mm, 90mm, 95mm, 100mm, 105mm, 110mm, or 115mm. Limiting the diameter D of the motor's stator core restricts the range of magnetic flux linkage through the stator core. The outer diameter of the stator lamination is related to the length of the stator magnetic circuit. Increasing the outer diameter of the stator lamination increases motor leakage flux, weakens the magnetic flux linkage, and increases the motor's magnetic reluctance, ultimately affecting the motor's output power. This ensures that the stator provides higher performance and guarantees higher motor efficiency within a suitable magnetic field density range.

[0040] Furthermore, the minimum width of the stator tooth 20 on the side near the stator yoke 10 is Wt, satisfying 3mm ≤ Wt ≤ 10mm. For example, Wt can be 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, or 9.5mm. Q*Wt represents the total width of the stator tooth 20. The magnetic flux provided by the permanent magnet 30 passes entirely through the stator tooth 20, limiting the total tooth width range so that the magnetic field density of the stator tooth 20 is within a suitable range, providing high performance and ensuring high motor efficiency.

[0041] Furthermore, the design parameters of three 10-pole 15-slot motors are shown below, and the efficiency of the three 10-pole 15-slot motors under the same operating conditions is investigated. Table 1 shows the three motor design schemes with different K values, and Table 2 compares the motor efficiency of the three schemes in Table 1 under the same operating conditions.

[0042]

[0043] As shown in Table 1, different values ​​were assigned to the stator lamination diameter D, the minimum width Wt of the stator tooth 20 near the stator yoke 10, the cross-sectional area S of the permanent magnet 30, the saturation magnetic density Bm of the silicon steel sheet, and the remanence Br of the permanent magnet 30 in the three motor design schemes. The evaluation coefficient of Scheme 1 was 25.06, which is lower than the minimum value of the evaluation coefficient K range; the evaluation coefficient of Scheme 2 was 58.47, which is within the evaluation coefficient K range; and the evaluation coefficient of Scheme 3 was 143.73, which is higher than the maximum value of the evaluation coefficient K range.

[0044]

[0045] Furthermore, referring to Table 2, under operating condition 1 (1260 rpm / 1.04 Nm), the motor in Scheme 1 has the best efficiency, followed by the motor in Scheme 2, and lastly the motor in Scheme 3; under operating condition 2 (5100 rpm / 2.0 Nm), the motor in Scheme 2 has the best efficiency, followed by the motor in Scheme 1, and lastly the motor in Scheme 3.

[0046] Combining Tables 1 and 2, the motor in Scheme 1 has the best efficiency under operating condition 1. However, its evaluation coefficient K is lower than the minimum value within the specified range, and the amount of permanent magnets used in Scheme 1 is 1.43 times that of Scheme 2 (obtained from the cross-sectional area ratio of the permanent magnets). Furthermore, the operating efficiencies of the motors in Scheme 1 and Scheme 2 are quite similar under operating condition 1. Therefore, compared to the motor in Scheme 2, the utilization rate of permanent magnets in Scheme 1 is lower, which is equivalent to increasing the cost of the motor. Scheme 3 has the lowest amount of permanent magnets, 0.73 times that of the motor in Scheme 2. However, the motor efficiency of Scheme 3 is significantly lower than that of the motor in Scheme 2 under both operating conditions.

[0047] Therefore, Scheme 1 has better motor efficiency, but uses more permanent magnets, resulting in lower permanent magnet utilization and higher cost compared to Scheme 2. Scheme 3 uses the fewest permanent magnets, but its motor efficiency is lower than the other two schemes. Therefore, Scheme 2, which falls within the K coefficient range, combines the advantages of high motor efficiency and low cost.

[0048] Therefore, by forming an evaluation coefficient K from the parameters related to motor efficiency, the evaluation coefficient K can limit the minimum amount of permanent magnets to ensure motor efficiency, and limit the maximum amount of permanent magnets to ensure the material utilization rate of rare earth materials, thereby reducing motor costs; motors that meet the value range of the evaluation coefficient K have the advantages of both high efficiency and low cost.

[0049] This utility model embodiment also provides a compressor, including the motor described above. Since the compressor includes the aforementioned motor, it achieves all the technical effects of the motor described above, which will not be repeated here.

[0050] This utility model embodiment also provides a refrigeration device, including the compressor described above. This refrigeration device can include the compressor described above, and therefore can achieve all the technical effects of the above compression, which will not be elaborated further here.

[0051] In summary, the motor, compressor, and refrigeration equipment provided by this utility model have the following advantages:

[0052] By forming an evaluation coefficient K from parameters related to motor efficiency, a motor that meets the value range of evaluation coefficient K can achieve both high efficiency and low cost.

[0053] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. An electric machine characterized in that, Comprising: a stator comprising a stator core, the stator core comprising a plurality of stator laminations stacked together, the stator laminations comprising a stator yoke portion and a plurality of stator teeth circumferentially arranged along an inner circle of the stator yoke portion, a stator slot being formed between two adjacent stator teeth, a rotor comprising a rotor core and a plurality of permanent magnets, the rotor core being provided with a plurality of magnet slots, the permanent magnets being arranged in the magnet slots; the number of stator slots is Q, the outer diameter of the stator lamination is D, the shortest width of the stator tooth is Wt, the cross-sectional area of the permanent magnet perpendicular to the motor axis is S, the saturation magnetic density of the stator lamination is Bm, the residual magnetism of the permanent magnet is Br, the Q, the Wt, the D, the Bm and the Br form an evaluation coefficient K, K = Q Wt D Bm / (S Br), satisfying the relationship: 30 ≤ K ≤ 140.

2. The electric machine of claim 1, wherein, a number of the stator slots is Q, a number of poles of the rotor is P, and the Q and the P satisfy Q / P=3:

2.

3. The electric machine of claim 1, wherein, The stator lamination is a silicon steel sheet.

4. The electric machine of claim 3, wherein, A saturation magnetic flux density Bm of the silicon steel sheet satisfies 1.7T≤Bm≤2.5T.

5. The electric machine of claim 1, wherein, The Br satisfies 1.25T≤Br≤1.6T.

6. The electric machine of claim 1, wherein, S satisfies: 100 mm 2 ≤ S ≤ 280 mm 2 .

7. The electric machine of claim 1, wherein, The D satisfies 80mm≤D≤120mm.

8. The electric machine of claim 1, wherein, A width of the stator tooth on a side close to the stator yoke portion is Wt, and 3mm≤Wt≤10mm is satisfied.

9. A compressor characterized by, A motor comprising any one of the stators according to claims 1 to 8.

10. A refrigeration appliance characterized in that, A compressor comprising the motor according to claim 9.

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