Stator structure, permanent magnet motor and rotor compressor

Abstract

This invention provides a stator structure, a permanent magnet motor, and a rotor compressor. The stator structure includes: a stator core, comprising a yoke and multiple stator teeth. The yoke is an annular structure, and the multiple stator teeth are sequentially and spaced apart along the circumference of the stator structure on the inner wall surface of the yoke, with stator slots formed between any two adjacent stator teeth; and a stator winding disposed on the multiple stator teeth and multiple stator slots. The stator winding is at least partially formed by winding composite wire, which includes a first wire and a second wire covering the surface of the first wire. The second wire is copper wire, and the resistivity ρ of the composite wire at 20°C satisfies 0.022 Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 / m; The stator core structure satisfies: 5.5≤L1*L2*Z / R3≤11.5, where L1 is the thickness of the yoke, L2 is the width of the stator teeth, Z is the number of stator slots, and R3 is the radius of the circumscribed circle of the stator core. The stator structure of this invention solves the technical problem of excessively high motor material costs in related technologies.

Description

Technical Field

[0001] This invention relates to the field of motor design, and more specifically, to a stator structure, a permanent magnet motor, and a rotor compressor. Background Technology

[0002] In related technologies, the enameled wire of motors mainly uses copper wire, and the cost of copper wire can account for 30% to 40% of the motor's material cost. Given the performance requirements of the motor, the amount of copper wire used cannot be further reduced. To reduce the manufacturing cost of motors, related technologies typically reduce the amount of permanent magnets or silicon steel used, or change the material. Some solutions also use aluminum wire windings, but these have problems such as high manufacturing difficulty, poor contact due to electro-corrosion caused by potential differences between the aluminum conductor and copper terminals, and poor reliability.

[0003] It is evident that the relevant technologies suffer from the problem of excessively high motor material costs, and no effective solution has yet been proposed to address this issue. Summary of the Invention

[0004] The main objective of this invention is to provide a stator structure, a permanent magnet motor, and a rotor compressor to solve the technical problem of excessively high motor material costs in related technologies.

[0005] To achieve the above objectives, according to one aspect of the present invention, a stator structure is provided, comprising: a stator core, the stator core including a yoke and a plurality of stator teeth, the yoke being an annular structure, the plurality of stator teeth being sequentially and spaced apart along the circumference of the stator structure on the inner wall surface of the yoke, and a stator slot being formed between any two adjacent stator teeth; and a stator winding disposed on the plurality of stator teeth and the plurality of stator slots; wherein the stator winding is at least partially formed by winding composite wire, the composite wire including a first wire and a second wire covering the surface of the first wire, the second wire being copper wire, and the resistivity ρ of the composite wire at 20°C satisfying 0.022 Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 / m; The structure of the stator core satisfies: 5.5≤L1*L2*Z / R3≤11.5, where L1 is the thickness of the yoke, L2 is the width of the stator teeth, Z is the number of stator slots, and R3 is the radius of the circumscribed circle of the stator core.

[0006] Furthermore, the structure of the stator core satisfies: 0.51≤R1 / R3≤0.53, where R1 is the radius of the inscribed circle of the stator core.

[0007] Furthermore, the number of stator slots is 12, and the stator structure satisfies: 5.0mm≤L1≤6.0mm, 5.5mm≤L2≤6.5mm.

[0008] Furthermore, the number of stator slots is 9, and the stator structure satisfies: 5.8mm≤L1≤7.2mm, 8.0mm≤L2≤9.0mm.

[0009] Furthermore, the first wire is an aluminum wire, and the copper wire has a cylindrical structure, with the copper wire sleeved on the outside of the aluminum wire.

[0010] Furthermore, the mass ratio of copper to aluminum in the composite wire satisfies: 1 ≤ copper: aluminum ≤ 3.

[0011] According to another aspect of the present invention, a permanent magnet motor is provided, comprising: a stator structure, wherein the stator structure is as described above; and a rotor structure, wherein the rotor structure is rotatably mounted within the stator structure.

[0012] Furthermore, the rotor structure is provided with multiple magnetic slots, which are V-shaped with the openings of the V-shaped structures facing away from the center of the rotor structure. The multiple magnetic slots are arranged sequentially at intervals along the circumference of the rotor structure.

[0013] Furthermore, the magnetic steel groove includes two groove segments with different extension directions. For any one groove segment, it satisfies 5.2≤L4 / L3≤6.5, where L4 is the length of the groove segment projected in the preset plane, and L3 is the width of the groove segment projected in the preset plane. The preset plane is a plane perpendicular to the axis of the permanent magnet motor.

[0014] According to another aspect of the present invention, a rotary compressor is provided, which includes the aforementioned permanent magnet motor.

[0015] The stator structure of this invention includes: a stator core, the stator core comprising a yoke and a plurality of stator teeth, the yoke being an annular structure, the plurality of stator teeth being sequentially and spaced apart along the circumference of the stator structure on the inner wall surface of the yoke, and a stator slot being formed between any two adjacent stator teeth; and a stator winding, the stator winding being disposed on the plurality of stator teeth and the plurality of stator slots; wherein, the stator winding is at least partially formed by winding composite wire, the composite wire comprising a first wire and a second wire covering the surface of the first wire, the second wire being copper wire, and the resistivity ρ of the composite wire at 20°C satisfying 0.022Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 / m; The stator core structure satisfies: 5.5≤L1*L2*Z / R3≤11.5, where L1 is the thickness of the yoke, L2 is the width of the stator teeth, Z is the number of stator slots, and R3 is the radius of the circumscribed circle of the stator core. The stator structure using this design employs a composite wire with a copper outer layer wound around the stator winding. Furthermore, the resistivity ρ of this composite wire is controlled to meet the requirement of 0.022Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2The stator core structure is specifically optimized to meet the requirement of 5.5 ≤ L1*L2*Z / R3 ≤ 11.5, thus ensuring the performance of the manufactured motor. Specifically, for L1*L2*Z / R3, if it is too large, it will reduce the slot area of ​​the stator structure and the wire diameter that can be used in the stator winding, resulting in excessively high current density in the stator winding and severe motor overheating. If it is too small, it will result in excessively high magnetic flux density in the teeth and yoke of the stator core, increasing iron losses and thus reducing motor performance. For the resistivity ρ of the composite wire, if it is too large, it will increase the resistance of the composite wire, affecting motor performance. If it is too small, it will lead to excessive copper usage, increasing motor cost. This embodiment of the invention, based on using composite wire with a copper outer layer to wind the stator winding, further controls the resistivity ρ and L1*L2*Z / R3 to meet the motor performance requirements. By using composite wire with an outer copper layer to replace the copper wire in related technologies, the material cost of the motor can be effectively reduced while maintaining the motor's performance, thus solving the technical problem of excessively high motor material costs in related technologies. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0017] Figure 1 This is a schematic diagram of an embodiment of the stator structure of the present invention;

[0018] Figure 2 This is a schematic diagram of the rotor structure of the permanent magnet motor of the present invention;

[0019] Figure 3 This is a schematic diagram comparing the performance and cost of a permanent magnet motor according to an embodiment of the present invention with that of a permanent magnet motor in related technologies.

[0020] The above figures include the following reference numerals:

[0021] 1. Stator core; 11. Yoke; 12. Stator teeth; 13. Stator slot; 2. Stator winding; 10. Stator structure; 20. Rotor structure; 21. Magnet slot; 211. Slot segment. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] Please refer to Figure 1To achieve the above objectives, embodiments of the present invention provide a stator structure comprising: a stator core 1, the stator core 1 including a yoke 11 and a plurality of stator teeth 12, the yoke 11 being annular, the plurality of stator teeth 12 being sequentially and spaced apart along the circumference of the stator structure on the inner wall surface of the yoke 11, and a stator slot 13 being formed between any two adjacent stator teeth 12; and a stator winding 2, the stator winding 2 being disposed on the plurality of stator teeth 12 and the plurality of stator slots 13; wherein the stator winding 2 is at least partially formed by winding composite wire, the composite wire including a first wire and a second wire covering the surface of the first wire, the second wire being copper wire, and the resistivity ρ of the composite wire at 20°C satisfying 0.022Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 / m; The structure of stator core 1 satisfies: 5.5≤L1*L2*Z / R3≤11.5, where L1 is the thickness of yoke 11, L2 is the width of stator tooth 12, Z is the number of stator slots 13, and R3 is the radius of the outer circle of stator core 1.

[0024] The stator structure using this design employs a composite wire with a copper outer layer wound around stator winding 2. Furthermore, the resistivity ρ of this composite wire is controlled to meet the requirement of 0.022 Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 The stator core 1 structure is specifically optimized to meet the condition 5.5≤L1*L2*Z / R3≤11.5, thus ensuring the performance of the manufactured motor. Specifically, if L1*L2*Z / R3 is too large, it will reduce the slot area of ​​the stator structure and the wire diameter that can be used in the stator winding, resulting in excessively high current density in the stator winding 2 and severe motor overheating. If it is too small, it will result in excessively high magnetic flux density in the teeth and yoke of the stator core 1, increasing iron losses and thus reducing motor performance. Similarly, if the resistivity ρ of the composite wire is too large, it will increase the resistance of the composite wire, affecting motor performance. If it is too small, it will lead to excessive copper usage, increasing motor cost. This embodiment of the invention, based on using composite wire with a copper outer layer to wind the stator winding 2, further controls the resistivity ρ and L1*L2*Z / R3 to meet the motor performance requirements. By using composite wire with an outer copper layer to replace the copper wire in related technologies, the material cost of the motor can be effectively reduced while maintaining the motor's performance, thus solving the technical problem of excessively high motor material costs in related technologies.

[0025] In actual implementation, the composite wire is provided with an insulating coating, that is, it is an enameled wire structure. The thickness of the yoke 11 mentioned above is the radial thickness of the yoke 11 of the stator structure, and the width of the stator tooth 12 is the circumferential width of the stator tooth 12.

[0026] In a preferred embodiment, the structure of the stator core 1 satisfies: 0.51≤R1 / R3≤0.53, where R1 is the radius of the inscribed circle of the stator core 1.

[0027] In this embodiment, the value of R1 / R3 is further designed to satisfy 0.51≤R1 / R3≤0.53. If R1 / R3 is too large, exceeding 0.53, it will lead to an excessively large stator inner diameter, thereby reducing the slot area, increasing the current density, and causing severe motor overheating. If R1 / R3 is too small, below 0.51, it will lead to an excessively small rotor outer diameter, thereby reducing its moment of inertia. During high-speed motor operation, the control performance will deteriorate, making the motor prone to runaway. This embodiment avoids the above situations by designing R1 / R3 to be 0.51≤R1 / R3≤0.53, resulting in less motor overheating and better control performance.

[0028] In practical implementation, the number of slots and poles of the motor can be selected in various ways, and therefore the number of stator slots 13 on the stator core 1 can also vary. For different stator slot 13 schemes, the structure of the stator core 1 also needs to be designed accordingly to better match the use of composite wires, for example:

[0029] In an optional embodiment, the number of stator slots 13 is 12, and the stator structure satisfies: 5.0mm≤L1≤6.0mm, 5.5mm≤L2≤6.5mm.

[0030] In another optional embodiment, the number of stator slots 13 is 9, and the stator structure satisfies: 5.8mm≤L1≤7.2mm, 8.0mm≤L2≤9.0mm.

[0031] Different numbers of stator slots 13 affect the magnetic flux density of the teeth and yoke, which in turn affects the current density, iron loss, and performance of the stator winding 2. By adjusting the dimensions of the yoke 11 and stator teeth 12, the slot area can be controlled, thereby controlling the current density, iron loss, and ultimately the motor's heat generation and performance. Specifically, if L1 or L2 is too large, the magnetic flux density of the teeth and yoke will be too low, the slot area will be small, and the current density will increase, resulting in greater heat generation in the motor. If L1 or L2 is too small, the magnetic flux density of the teeth and yoke will be too high, leading to excessive iron loss and poor motor performance. Embodiments of this invention specifically design stator structures with 12 and 9 stator slots 13, controlling the dimensions of L1 and L2 to better control the motor's heat generation and performance.

[0032] In a preferred embodiment, the first wire is an aluminum wire, and the copper wire has a cylindrical structure, with the copper wire sleeved on the outside of the aluminum wire.

[0033] Because conductors exhibit the skin effect when carrying alternating current or an alternating magnetic field, meaning the current concentrates on the conductor's surface, and this effect becomes more pronounced at higher frequencies, the outer surface of the conductor becomes the primary current path. In embodiments of this invention, the outer second wire is made of copper, effectively ensuring the conductivity of the composite wire winding. The inner first wire can be replaced with a material with lower conductivity, thereby reducing costs. In practical implementation, the inner first wire of the composite wire can be flexibly selected according to actual needs.

[0034] In this preferred embodiment, the first wire inside the composite wire is made of aluminum wire. Under the same resistivity, aluminum wire has a cost advantage compared with wires made of other materials, thereby ensuring better motor performance while reducing material costs.

[0035] Specifically, the mass ratio of copper to aluminum in the composite wire satisfies: 1 ≤ copper: aluminum ≤ 3.

[0036] Because copper has a much higher density than aluminum, when copper and aluminum are combined of equal mass, copper is only a thin layer on the surface. If the mass ratio of copper to aluminum is too small, that is, too much aluminum is used, the advantage of the skin effect will not be obvious, which will lead to low motor performance. If the mass ratio of copper to aluminum is too large, that is, too much copper is used, the motor cost will be too high and the cost performance will be low.

[0037] In addition, embodiments of the present invention also provide a permanent magnet motor, such as Figure 1 and Figure 2 As shown, the permanent magnet motor includes: a stator structure 10, which is the stator structure described above; and a rotor structure 20, which is rotatably mounted within the stator structure 10.

[0038] Specifically, the rotor structure 20 is provided with a plurality of magnetic steel slots 21, which are V-shaped structures with the opening direction of the V-shaped structure facing away from the center of the rotor structure 20. The plurality of magnetic steel slots 21 are arranged sequentially at intervals along the circumference of the rotor structure 20.

[0039] like Figure 2 As shown, the magnet slot 21 includes two slot segments 211 with different extension directions. For any slot segment 211, it satisfies 5.2≤L4 / L3≤6.5, where L4 is the length of the projection of the slot segment 211 in the preset plane, and L3 is the width of the projection of the slot segment 211 in the preset plane. The preset plane is a plane perpendicular to the axis of the permanent magnet motor.

[0040] In this embodiment, the aspect ratio of each slot segment 211 is also designed, namely 5.2≤L4 / L3≤6.5. If L4 / L3 is too small, a large number of magnets are required, resulting in a high overall cost of the motor; if L4 / L3 is too large, the magnetic flux is reduced too much, leading to a decrease in motor performance. In this embodiment, by controlling 5.2≤L4 / L3≤6.5, the performance and cost of the motor can be well balanced. Combined with the copper-clad wire structure design mentioned above, the cost of the motor can be further reduced while ensuring motor performance, thus solving the technical problem of excessively high motor costs in related technologies.

[0041] In a preferred embodiment, the permanent magnet motor is a concentrated winding motor. Figure 3 This is a schematic diagram comparing the performance and cost of a permanent magnet motor according to an embodiment of the present invention with that of a permanent magnet motor in related technologies, as shown below. Figure 3 As shown, for this model of motor, item A represents the performance of the permanent magnet motor (energy efficiency under GB60rps conditions), item B represents the motor cost (yuan), and the left side shows a permanent magnet motor using copper wire windings in related technologies, where the resistivity of the copper wire is 0.0171Ω*mm. 2 / m, the right side shows a permanent magnet motor with copper-clad aluminum wire windings according to an embodiment of the present invention, wherein the resistivity of the copper-clad aluminum wire is 0.0252Ω*mm. 2 / m. It can be seen that the efficiency of the permanent magnet motor using copper wire is 88.30%, while the efficiency of the motor using copper-clad aluminum wire is 88.10%, showing almost no difference in performance. However, the cost of the permanent magnet motor using copper wire is 65 yuan, while the cost of the permanent magnet motor using copper-clad aluminum wire is 59 yuan, effectively reducing costs. It can be seen that the permanent magnet motor designed with the above-mentioned copper-clad aluminum wire structure in this embodiment of the invention can effectively reduce the cost of the motor without significantly affecting performance, solving the technical problem of excessively high motor material costs in related technologies, and has great application value.

[0042] Finally, embodiments of the present invention also provide a rotary compressor, which includes the aforementioned permanent magnet motor.

[0043] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0044] The stator structure of this embodiment includes: a stator core 1, which includes a yoke 11 and a plurality of stator teeth 12. The yoke 11 is an annular structure, and the plurality of stator teeth 12 are sequentially and spaced apart on the inner wall surface of the yoke 11 along the circumference of the stator structure, with stator slots 13 formed between any two adjacent stator teeth 12; and a stator winding 2, which is disposed on the plurality of stator teeth 12 and the plurality of stator slots 13. The stator winding 2 is at least partially formed by winding composite wire, which includes a first wire and a second wire covering the surface of the first wire. The second wire is copper wire, and the resistivity ρ of the composite wire at 20°C satisfies 0.022 Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 / m; The structure of stator core 1 satisfies: 5.5≤L1*L2*Z / R3≤11.5, where L1 is the thickness of the yoke 11, L2 is the width of the stator teeth 12, Z is the number of stator slots 13, and R3 is the radius of the circumscribed circle of stator core 1. The stator structure using this design employs a composite wire with a copper outer layer wound around stator winding 2. Furthermore, the resistivity ρ of this composite wire is controlled to meet the requirement of 0.022Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 The stator core 1 structure is specifically optimized to meet the condition 5.5≤L1*L2*Z / R3≤11.5, thus ensuring the performance of the manufactured motor. Specifically, if L1*L2*Z / R3 is too large, it will reduce the slot area of ​​the stator structure and the wire diameter that can be used in the stator winding, resulting in excessively high current density in the stator winding 2 and severe motor overheating. If it is too small, it will result in excessively high magnetic flux density in the teeth and yoke of the stator core 1, increasing iron losses and thus reducing motor performance. Similarly, if the resistivity ρ of the composite wire is too large, it will increase the resistance of the composite wire, affecting motor performance. If it is too small, it will lead to excessive copper usage, increasing motor cost. This embodiment of the invention, based on using composite wire with a copper outer layer to wind the stator winding 2, further controls the resistivity ρ and L1*L2*Z / R3 to meet the motor performance requirements. By using composite wire with an outer copper layer to replace the copper wire in related technologies, the material cost of the motor can be effectively reduced while maintaining the motor's performance, thus solving the technical problem of excessively high motor material costs in related technologies.

[0045] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0046] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0047] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A stator structure, characterized in that, include: Stator core (1), the stator core (1) includes a yoke (11) and a plurality of stator teeth (12), the yoke (11) is an annular structure, the plurality of stator teeth (12) are arranged sequentially and spaced apart on the inner wall surface of the yoke (11) along the circumference of the stator structure, and a stator slot (13) is formed between any two adjacent stator teeth (12); Stator winding (2), the stator winding (2) is disposed on a plurality of stator teeth (12) and a plurality of stator slots (13); The stator winding (2) is at least partially formed by winding composite wire, which includes a first wire and a second wire covering the surface of the first wire. The second wire is copper wire, and the resistivity ρ of the composite wire at 20°C satisfies 0.022 Ω*mm. 2 / m≤ρ≤0.026Ω*mm 2 / m; The structure of the stator core (1) satisfies: 5.5≤L1*L2*Z / R3≤11.5, where L1 is the thickness of the yoke (11), L2 is the width of the stator teeth (12), Z is the number of stator slots (13), and R3 is the radius of the circumscribed circle of the stator core (1).

2. The stator structure according to claim 1, characterized in that, The structure of the stator core (1) satisfies: 0.51≤R1 / R3≤0.53, where R1 is the radius of the inscribed circle of the stator core (1).

3. The stator structure according to claim 1, characterized in that, The number of stator slots (13) is 12, and the stator structure satisfies: 5.0mm≤L1≤6.0mm, 5.5mm≤L2≤6.5mm.

4. The stator structure according to claim 1, characterized in that, The number of stator slots (13) is 9, and the stator structure satisfies: 5.8mm≤L1≤7.2mm, 8.0mm≤L2≤9.0mm.

5. The stator structure according to any one of claims 1 to 4, characterized in that, The first wire is an aluminum wire, and the copper wire has a cylindrical structure, with the copper wire sleeved on the outside of the aluminum wire.

6. The stator structure according to claim 5, characterized in that, The mass ratio of copper to aluminum in the composite wire satisfies: 1 ≤ copper: aluminum ≤ 3.

7. A permanent magnet motor, characterized in that, include: Stator structure (10), wherein the stator structure (10) is the stator structure according to any one of claims 1 to 6; The rotor structure (20) is rotatably mounted within the stator structure (10).

8. The permanent magnet motor according to claim 7, characterized in that, The rotor structure (20) is provided with a plurality of magnetic steel slots (21), the magnetic steel slots (21) are V-shaped structures, the opening direction of the V-shaped structure is away from the center of the rotor structure (20), and the plurality of magnetic steel slots (21) are arranged sequentially at intervals along the circumference of the rotor structure (20).

9. The permanent magnet motor according to claim 8, characterized in that, The magnetic steel groove (21) includes two groove segments (211) with different extension directions. For any one of the groove segments (211), it satisfies 5.2≤L4 / L3≤6.5, where L4 is the length of the projection of the groove segment (211) in the preset plane, and L3 is the width of the projection of the groove segment (211) in the preset plane. The preset plane is a plane perpendicular to the axis of the permanent magnet motor.

10. A rotary compressor, characterized in that, The rotary compressor includes the permanent magnet motor as described in claim 9.

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