Electric machine, compressor and refrigeration plant

Abstract

The application discloses a motor, a compressor and a refrigeration device, relates to the technical field of the refrigeration device, and discloses a motor, a compressor and a refrigeration device, wherein the stator slot comprises a first stator slot and a second stator slot, the cross-sectional area of the first stator slot is larger than that of the second stator slot, the maximum radius of the outer periphery of the stator lamination is R1, the maximum distance from the slot wall of the first stator slot to the center of the stator lamination is R0, the length of the stator core in the axial direction is h, the elastic modulus of the stator core is E, the density of the stator core is p, and the Poisson's ratio of the stator core is v, and the condition is met: 3000Hz<=f*sqrt(E / (rho*v))<=5000Hz. The technical scheme provided by the application improves the rigidity of the stator and reduces the electromagnetic noise of the motor.

Description

Technical Field

[0001] This invention relates to the technical field of refrigeration equipment, and particularly to a motor, a compressor, and refrigeration equipment. Background Technology

[0002] Given the continuous evolution of the home appliance industry, the requirements for overall machine performance, noise control, and size constraints are becoming increasingly stringent. This trend is also evident in the field of compressor design, especially in home appliances and industrial applications. Compressors are moving towards high-performance, low-noise, and compact designs, which directly places higher demands on the electromagnetic-mechanical performance of the compressor's core components. In existing technologies, stator laminations generally employ a large split-ratio design to optimize electromagnetic efficiency, but this reduces the natural frequency of the stator structure, leading to excessive electromagnetic noise under high-speed or variable-load conditions. Summary of the Invention

[0003] The main objective of this invention is to provide an electric motor, compressor, and refrigeration equipment that aims to improve the rigidity of the stator and reduce the electromagnetic noise of the motor.

[0004] To achieve the above objectives, the present invention provides a motor comprising:

[0005] The stator includes a stator core, which comprises multiple stator laminations. Each stator lamination has a stator slot, including a first stator slot and a second stator slot. The cross-sectional area of ​​the first stator slot is larger than that of the second stator slot. The maximum radius of the outer periphery of each stator lamination is R1. The maximum distance from the wall of the first stator slot to the center of the stator lamination is R0. The axial length of the stator core is h. The elastic modulus of the stator core is E. The density of the stator core is ρ. The Poisson's ratio of the stator core is v. The condition 3000Hz ≤ × ≤5000Hz.

[0006] In one embodiment, the minimum radius of the inner periphery of the stator lamination is R2, satisfying the condition: 0.45 ≤ <0.5, 0.3≤ <0.41.

[0007] In one implementation, the condition is satisfied: 0.15 ≤ <0.22.

[0008] In one embodiment, the motor further includes a rotor, which includes a rotor core. The rotor core has filling slots. The maximum radius of the outer periphery of the rotor core is R3, and the minimum radius of the inner periphery of the rotor core is R4. The maximum width of the filling slot along the radial direction of the rotor core is d0, and the maximum width of the filling slot along the tangential direction of the outer periphery of the rotor core is d1. The number of filling slots is m, satisfying the condition: 0.5 ≤ 1. ≤0.7.

[0009] In one implementation, the following condition is met: >1.

[0010] In one embodiment, the rotor core includes an upper convex section, a main body section, and a lower convex section connected in sequence, and the filling groove is disposed in the main body section and extends through the main body section.

[0011] In one embodiment, the length of the main body segment along the axial direction of the rotor core is T, satisfying the condition: 0.065 < ≤0.1.

[0012] In one embodiment, the outer periphery of the stator core is provided with a straight tangent and a tangent groove, the straight tangent and the tangent groove being disposed opposite to the second stator slot.

[0013] The present invention also proposes a compressor comprising the motor described above.

[0014] The present invention also proposes a refrigeration device, including the compressor described above.

[0015] The technical solution of the present invention × This is the formula for calculating the second natural frequency of the radial vibration of a thin-walled circular ring, where the second natural frequency represents the vibration mode order of the stator, n=2. Where E, ρ, and v are all constants, in one embodiment, E = 200 GPa and ρ = 7800 kg / m³. 3 v = 0.3 (dimensionless), defined × Therefore, the main factor affecting f is And h, if f > 5000Hz, then it means Too small, where R0 represents the maximum distance from the wall of the first stator slot to the center of the stator lamination, therefore A smaller value indicates a thicker yoke in the stator core, but this results in a smaller stator slot area. While a smaller value increases stator rigidity, it also results in insufficient stator slot area, limiting stator winding design and hindering high-efficiency motor design. Conversely, if f < 3000Hz, it indicates... If the frequency is too high, the yoke of the stator core will be thinner and the stator slot area will be larger, resulting in insufficient stiffness of the stator core and thus increasing the noise generated during operation. Therefore, by using 3000Hz≤f≤5000Hz, the stator modes and stiffness meet the requirements of the main excitation frequency of the misaligned electromagnetic circuit, thereby reducing the electromagnetic noise of the motor. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the structure of an embodiment of the motor provided by the present invention;

[0018] Figure 2 for Figure 1 A graph showing the trend of the f-value of a medium-sized motor in relation to motor vibration and energy efficiency improvement;

[0019] Figure 3 for Figure 1 Schematic diagram of the middle stator;

[0020] Figure 4 for Figure 1 A cross-sectional view of the rotor in the axial direction;

[0021] Figure 5 for Figure 1 Top view of the central rotor.

[0022] Explanation of icon numbers:

[0023] 10. Stator core; 11. First stator slot; 12. Second stator slot; 13. Straight cut edge; 14. Cut edge groove; 20. Rotor core; 21. Filler groove; 22. Upper convex section; 23. Main body section; 24. Lower convex section.

[0024] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0028] Reference Figures 1 to 3 The present invention proposes an electric motor, comprising:

[0029] The stator includes a stator core 10, which comprises multiple stator laminations. Each stator lamination has a stator slot, including a first stator slot 11 and a second stator slot 12. The cross-sectional area of ​​the first stator slot 11 is larger than that of the second stator slot 12. The maximum radius of the outer periphery of each stator lamination is R1. The maximum distance from the wall of the first stator slot 11 to the center of the stator lamination is R0. The axial length of the stator core 10 is h. The elastic modulus of the stator core 10 is E. The density of the stator core 10 is ρ. The Poisson's ratio of the stator core 10 is v, satisfying the condition: 3000Hz ≤ × ≤5000Hz.

[0030] The technical solution of the present invention × This is the formula for calculating the second natural frequency of the radial vibration of a thin-walled circular ring, where the second natural frequency represents the vibration mode order of the stator, n=2. Where E, ρ, and v are all constants, in one embodiment, E = 200 GPa and ρ = 7800 kg / m³. 3 v = 0.3 (dimensionless), defined × Therefore, the main factor affecting f is and h, refer to Figure 2 If f > 5000Hz, although the motor vibration is relatively low, the improvement in motor energy efficiency decreases significantly, indicating that... Too small, where R0 represents the maximum distance from the wall of the first stator slot 11 to the center of the stator lamination, therefore The smaller the value, the thicker the yoke of the stator core 10, but this results in a smaller stator slot area. While a smaller frequency (f < 3000Hz) increases stator rigidity, it also results in insufficient stator slot area, limiting stator winding design and hindering high-efficiency motor design. Conversely, if f < 3000Hz, the motor exhibits higher vibration and noise levels, indicating... If the frequency is too high, the yoke of the stator core 10 will be thinner and the stator slot area will be larger, resulting in insufficient stiffness of the stator core 10 and thus increasing the noise generated during operation. Therefore, by using 3000Hz≤f≤5000Hz, the vibration and energy efficiency improvement of the motor are maintained at an optimal level. This is mainly because the stator mode and stiffness meet the requirements of the main excitation frequency of the misaligned electromagnetic circuit, thereby reducing the electromagnetic noise and vibration of the motor and improving its energy efficiency.

[0031] The measurement method for R1 is as follows: Select two points on the outer periphery of the stator lamination. The line connecting these two points should be aligned with the radial direction of the stator lamination and pass through the center of the stator lamination. The distance between these two points is then measured as R1. Additionally, the outer periphery of the stator lamination may have tangled edges or other grooved structures; these structures should be avoided when selecting measurement points.

[0032] The method for measuring R0 is as follows: the point at which the maximum distance from the wall of the first stator slot 11 to the center of the stator lamination is located at the midpoint of the bottom of the first stator slot 11 (the slot wall of the first stator slot 11 facing the rotor direction). The distance between this point and the center of the stator lamination is then measured as R0.

[0033] The measurement method for h is as follows: Select one point on each of the two end faces of the stator core 10 along the axial direction. The line connecting these two points is aligned with the axial direction of the stator core 10. Then, measure the distance between these two points, which is h. The units for R1, R0, and h are all millimeters (mm).

[0034] Furthermore, the minimum radius of the inner periphery of the stator lamination is R2, satisfying the condition: 0.45 ≤ <0.5, 0.3≤ <0.41. The stator split ratio is expressed as 0.45≤ <0.5 indicates that the stator in the technical solution of the present invention does not optimize electromagnetic efficiency by using a large split ratio as in the prior art; Indicates the thickness of the stator lamination yoke; if ≥0.41 indicates Too large and / or Too small, if If the thickness is too large, it will result in an excessively thick yoke portion of the stator core 10, thereby reducing the area of ​​the stator slots. While this increases the rigidity of the stator core 10, it also increases the design complexity of the stator windings and reduces the energy efficiency of the motor. However, if... If the air gap is too small, it will reduce the air gap between the stator and rotor, increasing the difficulty of rotor installation, the risk of collision between the stator and rotor, and reducing the lifespan of the motor. <0.3 indicates Too small and / or Too large, when If the thickness is too small, the yoke thickness of the stator core 10 will be too small, resulting in insufficient stiffness of the stator core 10 and thus increasing the noise generated during operation; when If the air gap is too large, it indicates that the motor's air gap is too large, which leads to increased magnetic reluctance and consequently reduces the motor's energy efficiency. Therefore, by using 0.3≤ <0.41, thereby improving the rigidity of the stator, reducing the noise generated by the stator core 10, reducing the risk of stator and rotor collision during motor operation, and improving the service life of the motor.

[0035] R2 is measured in millimeters (mm). The method for measuring R2 is as follows: Select two points on the side of the stator lamination tooth shoe facing away from the stator yoke. The line connecting these two points should be aligned with the radial direction of the stator lamination and pass through its center. The distance between these two points is then measured as R2. It is important to avoid selecting points on the inner periphery of the stator lamination, as this will lead to an overestimation of the measured value.

[0036] Furthermore, the condition is satisfied: 0.15 ≤ <0.22. This indicates the thickness of the stator lamination yoke; therefore, if When ≥0.22, it indicates Too large and / or If the area is too small, both of these situations indicate that the thickness of the stator core yoke is large and the area of ​​the stator slots is small, resulting in insufficient stator slot area. This, in turn, limits the design of the stator winding scheme and makes it impossible to achieve a high-efficiency motor design. However, if... <0.15 indicates Too small and / or If the thickness is too large, both of these situations indicate that the thickness of the yoke portion of the stator core 10 is too small, resulting in insufficient stiffness of the stator core 10 and thus increasing the noise generated during operation. Therefore, by using 0.15≤ <0.22, thereby reasonably setting the thickness of the yoke of the stator core 10 and the area of ​​the stator slot, thereby improving the rigidity of the stator core 10 and improving the energy efficiency of the motor.

[0037] Reference Figure 4 and Figure 5 In one embodiment, the motor further includes a rotor, which includes a rotor core 20. The rotor core 20 has filling slots 21. The maximum radius of the outer periphery of the rotor core 20 is R3, and the minimum radius of the inner periphery of the rotor core 20 is R4. The maximum width of the filling slots 21 along the radial direction of the rotor core 20 is d0, and the maximum width of the filling slots 21 along the tangent direction of the outer periphery of the rotor core 20 is d1. The number of slots in the filling slots 21 is m, satisfying the condition: 0.5 ≤ 1. ≤0.7. Among them, This represents the total area of ​​the m filled slots 21. This indicates the area of ​​the annular region of the rotor core 20. It should be noted that the filling groove 21 is not square in shape. The total area of ​​the m filling slots 21 is larger than the actual total area, but we will not consider these factors here and will assume it is larger. Let 1 represent the total area of ​​m filled slots 21. This represents the ratio of the remaining area of ​​the rotor core 20 after removing the filling slot 21 to the total area of ​​the rotor core 20.

[0038] Therefore, if 1 - If the value is greater than 0.7, it indicates that the remaining area of ​​the rotor core 20 after removing the filling groove 21 is too large. While this increases the rigidity of the rotor core 20, it also reduces the area of ​​the shaft hole at the center of the rotor core 20. This makes installation of the rotor core 20 and the drive shaft more difficult, easily leading to deformation of the rotor core 20, resulting in edge cracking or localized stress concentration, thus affecting the magnetic circuit performance. However, if the value is 1- If the value is less than 0.5, it indicates that the remaining area of ​​the rotor core 20 after removing the filling slot 21 is too small, resulting in insufficient stiffness of the rotor core 20. This, in turn, increases the amplitude and frequency of rotor vibration during motor operation, thereby increasing the noise generated by the rotor. Therefore, 0.5 ≤ 1 - The value is ≤0.7, which improves the rigidity of the rotor core 20, thereby reducing rotor vibration during motor operation and reducing rotor noise. R3, R4, d0, and d1 are all in millimeters (mm).

[0039] The measurement method for R3 is as follows: Select two points on the outer periphery of the rotor core 20. The line connecting these two points should be aligned with the radial direction of the rotor core 20 and pass through the center of the rotor core 20. The distance between these two points is then measured as R3. Additionally, the outer periphery of the rotor core 20 may have tangential edges or other slotted structures; these structures should be avoided when selecting measurement points.

[0040] The measurement method for R4 is as follows: Select two points on the wall of the rotor lamination shaft hole. The line connecting these two points should be aligned with the radial direction of the rotor core 20 and pass through the center of the rotor core 20. The distance between these two points is then measured as R4. Furthermore, the points selected on the inner periphery of the rotor core 20 should avoid slotted or tangential structures on the inner periphery, as these will lead to an overestimation of the measurement result.

[0041] The method for measuring d0 is as follows: draw a straight line that bisects the filling groove 21, and the straight line passes through the center of the rotor core 20. Then measure the distance between the two intersection points of the straight line and the groove wall of the filling groove 21, which is d0.

[0042] The method for measuring d1 is as follows: Select the two widest regions of the filling groove 21 along the tangent direction of the rotor core 20, then select a point in each of these two regions, and measure the distance between the two points, which is d1. The smaller the range of the two regions, the higher the accuracy of the final measured d1 value.

[0043] Specifically, the following conditions must be met: >1. The ratio of the outer diameter to the inner diameter of the rotor core 20 is determined by... The ratio of the outer diameter to the inner diameter of the rotor core 20 is greater than 1, which optimizes the ratio of the outer diameter to the inner diameter of the rotor core 20, thereby improving the rigidity of the rotor core 20, reducing the vibration amplitude of the rotor core 20, reducing the vibration probability of the rotor core 20, and thus reducing the noise generated by the rotor core 20.

[0044] In one embodiment, the rotor core 20 includes an upper convex section 22, a main body section 23, and a lower convex section 24 connected in sequence. A filling groove 21 is located in and extends through the main body section 23. The filling groove 21 is filled with aluminum. The upper convex section 22 and the lower convex section 24 are injection molded together by filling the aluminum in the filling groove 21. Therefore, the upper convex section 22, the lower convex section 24, and the aluminum filling in the filling groove 21 are injection molded together. Consequently, the upper convex section and the lower convex section are also fixedly connected to the main body section, facilitating the production and manufacturing of the rotor.

[0045] Specifically, the length of the main body segment 23 along the axial direction of the rotor core 20 is T, satisfying the condition: 0.065 < ≤0.1, this is a dimensionless calculation. This indicates the rotor shaft system's resistance to deformation; therefore, when When the value is greater than 0.1, the rotor has strong resistance to deformation and high rigidity. However, the magnetic circuit of the rotor core 20 cannot achieve optimal design, leading to reduced motor efficiency. If... If the value is ≤0.065, it indicates that the rotor's resistance to deformation is weak and its rigidity is insufficient, which increases the rotor's vibration and, consequently, the noise generated during rotor operation.

[0046] In one embodiment, the outer periphery of the stator core 10 is provided with a straight tangent edge 13 and a tangent groove 14, which are disposed opposite to the second stator slot 12. Understandably, the cross-sectional areas of the first stator slot 11 and the second stator slot 12 are different. Therefore, by providing the straight tangent edge 13 and the tangent groove, the thickness difference of the yoke portion of the stator core 10 at the first stator slot 11 and the second stator slot 12 is reduced, thereby making the thickness of the yoke portion of the stator core 10 more uniform, resulting in a more uniform magnetic field distribution on the stator, thus improving the efficiency of the motor; and reducing magnetic field fluctuations, thereby reducing the noise and vibration of the motor.

[0047] The present invention also proposes a compressor, which includes a motor. The specific structure of the motor is as described in the above embodiments. Since the compressor in the present invention adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0048] The present invention also proposes a refrigeration device, which includes a compressor. The specific structure of the compressor is as described in the above embodiments. Since the refrigeration device in the present invention adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0049] The above description is merely an exemplary embodiment of the present invention and does not limit the scope of protection of the present invention. Any equivalent structural transformations made based on the technical concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. An electric machine characterized in that, Comprising: A stator comprises a stator core, the stator core comprises a plurality of stator sheets, the stator sheets are provided with stator slots, the stator slots comprise first stator slots and second stator slots, the cross-sectional area of the first stator slots is greater than the cross-sectional area of the second stator slots, the maximum radius of the outer periphery of the stator sheet is R1, the maximum distance from the slot wall of the first stator slot to the center of the stator sheet is R0, the length of the stator core in the axial direction is h, the elastic modulus of the stator core is E, the density of the stator core is p, and the Poisson's ratio of the stator core is v, and the conditions are met: 3000Hz≤ × ≤5000Hz.

2. The electric machine of claim 1, wherein, The minimum radius of the inner periphery of the stator lamination is R2, satisfying the condition: 0.45≤R2 / R1≤0.55 <0.5, 0.3≤ <0.

41.

3. The electric machine of claim 1, wherein, Satisfies condition: 0.15 ≤ <0.

22.

4. The electric machine of claim 1, wherein, The motor further comprises a rotor, the rotor comprising a rotor core, the rotor core being provided with a filling slot, a maximum radius of an outer periphery of the rotor core being R3, a minimum radius of an inner periphery of the rotor core being R4, a maximum width of the filling slot along a radial direction of the rotor core being d0, a maximum width of the filling slot along a tangential direction of the outer periphery of the rotor core being d1, and a slot number of the filling slot being m, satisfying the condition: 0.5≤1- ≤0.

7.

5. The electric machine of claim 4, wherein, Satisfies the condition: >

1.

6. The electric machine of claim 4, wherein, The rotor core comprises upper convex segments, main body segments and lower convex segments connected in sequence, and the filling groove is arranged in the main body segment and penetrates through the main body segment.

7. The electric machine of claim 6, wherein, The length of the main body section in the axial direction of the rotor core is T, and satisfies the condition: 0.065 < T < 0.

1. ≤0.

1.

8. The electric machine of claim 1, wherein, The outer periphery of the stator core is provided with a straight cutting edge and a cutting edge groove, and the straight cutting edge and the cutting edge groove are arranged opposite to the second stator slot.

9. A compressor characterized by, Comprising the electric machine according to any one of claims 1 to 8.

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

Images