Litz wire, stator, motor and vehicle

Abstract

The utility model relates to a Litz wire, a stator, a motor and a vehicle, the Litz wire comprises a wire body, the wire body comprises a first wire and a first insulating layer wrapping the peripheral surface of the first wire, and the first insulating layer is configured to be aluminum oxide. The first insulating layer is made of aluminum oxide, so that the heat resistance of the first insulating layer is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of Litz wire, in particular to a Litz wire, a stator, a motor and a vehicle. BACKGROUND

[0002] The Litz wire comprises a plurality of wire bodies twisted together. The wire body comprises a first conductor and a first insulating layer arranged on the outer circumferential surface of the first conductor.

[0003] In the related art, the material of the first insulating layer is polyimide, which enables the first insulating layer to work stably for a long time in the range of 200-400 degrees Celsius. However, once the temperature is higher, for example, when the temperature of the first insulating layer reaches 1000 degrees Celsius or above, the first insulating layer with polyimide material will undergo thermal degradation, thereby causing the first insulating layer to fail. It can be understood that the heat resistance of the first insulating layer with polyimide material is not high enough. CONTENT OF THE INVENTION

[0004] The embodiments of the present application provide a Litz wire, a stator, a motor and a vehicle, which improve the heat resistance of the first insulating layer to at least partially solve the above technical problems.

[0005] In order to achieve the above-mentioned purpose, according to the first aspect of the present application, a Litz wire is provided, comprising:

[0006] The wire body comprises a first conductor and a first insulating layer arranged on the outer circumferential surface of the first conductor, and the material of the first insulating layer is configured as aluminum oxide.

[0007] Optionally, the material of the first conductor is configured as aluminum.

[0008] Optionally, the thickness of the first insulating layer ranges from 10μm to 30μm.

[0009] Optionally, the wire body is provided with a plurality of wire bodies, and the Litz wire further comprises a connecting body connecting the plurality of wire bodies.

[0010] Optionally, the connecting body further covers the outer circumferential surface of the plurality of wire bodies.

[0011] And / or, the connecting body is provided with air holes.

[0012] And / or, the material of the connecting body is configured as an insulating material.

[0013] Optionally, the number of wire bodies ranges from 8 to 20.

[0014] And / or, the diameter of the first conductor ranges from 0.5mm to 0.6mm.

[0015] Optionally, a length dimension of a cross section of the litz wire ranges from 2mm to 3.5mm.

[0016] And / or, a width dimension of the cross section of the litz wire ranges from 1.4mm to 2mm.

[0017] According to a second aspect of the present application, a stator is provided, comprising:

[0018] a stator core body provided with a stator slot; and

[0019] the aforementioned litz wire is arranged in the stator slot.

[0020] Optionally, the stator further comprises a flat wire arranged in the stator slot.

[0021] Optionally, in the same stator slot, the litz wire is closer to a slot opening of the corresponding stator slot than the flat wire.

[0022] Optionally, in the same stator slot, a plurality of litz wires and a plurality of flat wires are arranged in sequence along a slot depth direction of the corresponding stator slot.

[0023] Optionally, the flat wire comprises a second wire and an insulator covering the second wire, and the second wire is made of copper or aluminum.

[0024] Optionally, a length dimension of a cross section of the second wire ranges from 2mm to 3.5mm.

[0025] And / or, a width dimension of the cross section of the second wire ranges from 1.4mm to 2mm.

[0026] And / or, the cross section of the second wire has a rounded corner, and a radius of the rounded corner ranges from 0.37mm to 0.43mm.

[0027] Optionally, a thickness of the insulator ranges from 40μm to 60μm.

[0028] According to a third aspect of the present application, an electric machine is further provided, comprising the aforementioned stator.

[0029] According to a fourth aspect of the present application, a vehicle is further provided, comprising the aforementioned electric machine.

[0030] In the Litz wire of the embodiment of the present application, the first insulating layer has a high melting point, the heat resistance of the first insulating layer 222 is improved, the melting point of the first insulating layer can reach more than 2000 degrees Celsius, and the first insulating layer can maintain structural integrity in a high-temperature environment. Secondly, the first insulating layer has a low thermal expansion coefficient, and when the temperature of the first insulating layer changes, the size of the first insulating layer changes less, reducing the risk of stress and potential rupture due to thermal expansion and contraction. Furthermore, the Litz wire can be directly welded, reducing the process step of removing the insulating paint before welding in the traditional enameled wire.

[0031] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0033] In order to more completely understand the present application and its beneficial effects, the following will be described in conjunction with the drawings, wherein the same reference numerals in the following description represent the same parts.

[0034] Figure 1 is a schematic cross-sectional view of a stator core, a Litz wire and a flat wire in the stator provided in the exemplary embodiment of the present disclosure;

[0035] Figure 2 is a partial schematic view of the cross section in Figure 1

[0036] Figure 3 is a schematic cross-sectional view of a Litz wire in Figure 2

[0037] Figure 4 is a schematic cross-sectional view of a wire body in Figure 3

[0038] Figure 5 is a schematic cross-sectional view of a flat wire in Figure 2

[0039] Legend of reference signs:

[0040] 100, stator core; 110, stator slot; 111, slot opening; 200, Litz wire; 210, connecting body; 220, wire body; 221, first conducting wire; 222, first insulating layer; 300, flat wire; 310, second conducting wire; 320, insulating body; 321, second insulating layer.​​​​ DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort are within the protection scope of the present application.

[0042] According to a first aspect of the present application, with reference to Figures 1 to 4 The present disclosure provides a Litz wire 200, the Litz wire 200 comprises a wire body 220, the wire body 220 comprises a first wire 221 and a first insulating layer 222 coated on the outer surface of the first wire 221, and the material of the first insulating layer 222 is configured as aluminum oxide. In this way, the first insulating layer 222 has a higher melting point, which improves the heat resistance of the first insulating layer 222, and the melting point of the first insulating layer 222 can reach more than 2000 degrees Celsius, so that the first insulating layer 222 can maintain structural integrity in a high-temperature environment. Secondly, the first insulating layer 222 has a lower thermal expansion coefficient, so that when the temperature of the first insulating layer 222 changes, the size change of the first insulating layer 222 is small, which reduces the risk of stress and potential rupture caused by thermal expansion and contraction. Furthermore, the Litz wire 200 can be directly welded, which reduces the process step of removing the insulating paint before welding in the traditional enameled wire.

[0043] In some embodiments, the material of the first wire 221 is configured as aluminum. Compared to the material of the first wire 221 being copper, the material of the first wire 221 being aluminum has significant cost and lightweight advantages. The density of copper is about 3 times that of aluminum. At the same resistance, the weight of the first wire 221 configured as copper is about 2 times that of the first wire 221 configured as aluminum, and the cost of the first wire 221 configured as copper is about 8 times that of the first wire 221 configured as aluminum. At the same volume, the weight of the first wire 221 configured as copper is about 3 times that of the first wire 221 configured as aluminum, and the cost of the first wire 221 configured as copper is about 12 times that of the first wire 221 configured as aluminum. Configuring the material of the first wire 221 as aluminum not only reduces the cost, but also reduces the weight of the Litz wire 200. It is worth mentioning that configuring the material of the first wire 221 as aluminum also facilitates the formation of the first insulating layer 222 with a material of aluminum oxide on the outer circumferential surface of the first wire 221 by anodic oxidation, and facilitates the close connection of the first wire 221 and the first insulating layer 222. However, the design is not limited to this. In some other embodiments, if the electrical conductivity of the Litz wire 200 is to be improved, the material of the first wire 221 can be configured as copper. The first wire 221 configured as copper has excellent electrical conductivity, which means that the current encounters less resistance when passing through the copper wire, thereby reducing energy loss (in the form of heat) and improving power transmission efficiency. The first wire 221 configured as copper has good mechanical strength and ductility. Copper not only has sufficient mechanical strength to support its own weight and cope with various stresses that may be encountered during installation, but its ductility and toughness also make it easy to process. The first wire 221 configured as copper has good thermal stability: copper has a high melting point and can work at high temperatures without losing its physical properties, which provides a guarantee for the safe operation of power equipment.

[0044] In some embodiments, the thickness of the first insulating layer 222 ranges from 10 μm to 30 μm. In this way, the Litz wire 200 is not too thick, which facilitates the lightweight of the Litz wire 200, shortens the heat dissipation path of the first wire 221 to the external environment, and facilitates the rapid dissipation of heat from the first wire 221 to the external environment. In addition, the Litz wire 200 is not too thin, so that the first insulating layer 222 is not easily broken down by high voltage when the Litz wire 200 is energized, and the first insulating layer 222 is not easily cracked. Exemplarily, the thickness of the first insulating layer 222 can be, but is not limited to, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, or 30 μm.

[0045] In some embodiments, the plurality of wire bodies 220 are provided, and the Litz wire 200 further comprises a connecting body 210 connecting the plurality of wire bodies 220. In this way, the connecting body 210 connects the plurality of wire bodies 220 more stably, which is conducive to keeping the relative poses of the plurality of wire bodies 220. In this way, when the Litz wire 200 is used, the plurality of wire bodies 220 are less likely to rub against each other, reducing the possibility of damage to the first insulating layer 222.

[0046] In some embodiments, the connecting body 210 further covers the outer circumferential surface of the plurality of wire bodies 220. In this way, it is conducive to protecting the first insulating layer 222 and reducing the possibility of cracking of the first insulating layer 222.

[0047] In some embodiments, the connecting body 210 is provided with air holes. In this way, it is conducive to improving the voltage resistance of the Litz wire 200.

[0048] In some embodiments, the material of the connecting body 210 is configured as an insulating material. In this way, it is conducive to further improving the insulation performance of the Litz wire 200. In an embodiment, the material of the connecting body 210 is configured as an epoxy resin; or, the material of the connecting body 210 is configured as a polyester imine drip impregnated resin; or, the material of the connecting body 210 is configured as a polyimide insulating paint, which can include low-dielectric particles to improve the voltage resistance of the Litz wire 200.

[0049] In some embodiments, the number of wire bodies 220 ranges from 8 to 20. The number of wire bodies 220 can be 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20.

[0050] In some embodiments, the diameter of the first conductor 221 ranges from 0.5 mm to 0.6 mm. In this way, the diameter of the first conductor 221 is not too small, which is conducive to reducing power loss and making the first conductor 221 have higher mechanical strength so that the first conductor 221 is less likely to break; in addition, the diameter of the first conductor 221 is also not too large, which is conducive to reducing the influence of skin effect and proximity effect of the Litz wire 200. The diameter of the first conductor 221 can be but is not limited to 0.5 mm, 0.55 mm, and 0.6 mm.

[0051] In some embodiments, the length dimension of the cross section of the Litz wire 200 ranges from 2 mm to 3.5 mm. The length dimension of the cross section of the Litz wire 200 can be but is not limited to 2 mm, 3 mm, and 3.5 mm.

[0052] In some embodiments, the width dimension of the cross section of the Litz wire 200 ranges from 1.4 mm to 2 mm. The width dimension of the cross section of the Litz wire 200 can be but is not limited to 1.4 mm, 1.5 mm, 1.8 mm, and 2 mm.

[0053] In some embodiments, the length dimension of the cross section of the Litz wire 200 ranges from 2mm to 3.5mm, and the width dimension of the cross section of the Litz wire 200 ranges from 1.4mm to 2mm. In this way, the cross section of the Litz wire 200 is relatively flat. When the Litz wire 200 is applied to the motor, the Litz wire 200 is arranged in the stator slot 110 of the motor, which is conducive to making the stator slot 110 have a higher slot fill rate and reducing the current loss. Exemplarily, the cross section of the Litz wire 200 can be but is not limited to a rectangle, a trapezoid, etc.

[0054] In a second aspect, the embodiments of the utility model provide a kind of stator, and the stator includes stator core 100 and the Litz wire 200 of preceding, which uses all technical solutions of above-mentioned embodiments, so at least have all beneficial effects brought by the technical solutions of above-mentioned embodiments.For example, the first insulating layer 222 has higher melting point, improves the heat resistance of the first insulating layer 222, and the melting point of the first insulating layer 222 can reach above 2000 degrees Celsius, so that the first insulating layer 222 can maintain structural integrity in high temperature environment.Secondly, the first insulating layer 222 has lower thermal expansion coefficient, when the temperature of the first insulating layer 222 changes, the size of the first insulating layer 222 changes less, reduces the risk of stress and potential rupture due to thermal expansion and contraction.Furthermore, the Litz wire 200 can be directly welded, which reduces the process step of removing insulating paint before welding in traditional enameled wire.

[0055] Here, it will not be described one by one again.Among them, stator core 100 is provided with stator slot 110, and Litz wire 200 is arranged in stator slot 110.

[0056] Referring to Figure 5 In some embodiments, the stator further includes flat wire 300 arranged in stator slot 110.The flat wire 300 is conducive to improving the slot fill rate of the stator slot 110 and reducing the current loss.The design is not limited thereto, and in some other embodiments, the stator further includes round wire arranged in the stator slot 110.

[0057] In an embodiment, the cross section of the Litz wire 200 is rectangularly arranged, and the cross section of the flat wire 300 is rectangularly arranged.This is conducive to making the motor applying the stator be called flat wire 300 motor, and the flat wire 300 motor has the advantages of high slot fill rate, wide efficient interval and high heat dissipation performance, etc.In the case of the same stator slot 110 of the motor, the number of windings in the stator slot 110 of the flat wire 300 motor is more, and the end size is smaller, so the motor can output higher power density and has higher working efficiency.

[0058] In the related art, the wire bundles in the stator slot 110 of the flat wire 300 motor are all flat wires 300, which makes the eddy current loss of the flat wire 300 motor at the slot opening 111 of the stator slot 110 more obvious, which can cause the copper loss and temperature rise of the flat wire 300 motor, and thus the efficiency of the flat wire 300 motor is reduced. Therefore, in some embodiments, in the same stator slot 110, the number of the Litz wire 200 is less than that of the flat wire 300. In this way, it is beneficial to reduce the eddy current loss of the motor.

[0059] In some embodiments, in the same stator slot 110, a plurality of Litz wires 200 and a plurality of flat wires 300 are arranged in sequence along the slot depth direction of the corresponding stator slot 110. In this way, it is beneficial to form a more uniform magnetic field in the motor. The slot depth direction of the stator slot 110 is indicated by the A direction in FIG. 1. Figure 2

[0060] In some embodiments, in the same stator slot 110, the number of the Litz wire 200 is 2 to 4, and the number of the flat wire 300 is 4 to 6. The number of the Litz wire 200 can be 2, 3, and 4. The number of the flat wire 300 can be 4, 5, and 6.

[0061] In an embodiment, in the same stator slot 110, the sum of the number of the Litz wire 200 and the number of the flat wire 300 ranges from 6 to 8. The sum of the number of the Litz wire 200 and the number of the flat wire 300 can be 6, 7, and 8. The sum of the number of the Litz wire 200 and the number of the flat wire 300 can be set according to actual needs, which is not limited herein.

[0062] In some embodiments, the flat wire 300 includes a second wire 310 and an insulator 320 covering the second wire 310, and the material of the second wire 310 is configured as copper or aluminum. If the material of the second wire 310 is configured as copper, it is beneficial to improve the electrical conductivity of the flat wire 300. If the material of the second wire 310 is configured as aluminum, it is beneficial to realize the lightweight of the second wire 310.

[0063] In some embodiments, the length dimension of the cross section of the second wire 310 ranges from 2 mm to 3.5 mm. The length dimension of the cross section of the second wire 310 can be but not limited to 2 mm, 3 mm, and 3.5 mm.

[0064] In some embodiments, the width dimension of the cross section of the second wire 310 ranges from 1.4 mm to 2 mm. The width dimension of the cross section of the second wire 310 can be but not limited to 1.4 mm, 1.5 mm, 1.8 mm, and 2 mm.

[0065] ​In some embodiments, the cross section of the second wire 310 has a fillet with a radius ranging from 0.37mm to 0.43mm. In this way, the size of the fillet is not too small, which is conducive to dispersing the stress of the second wire 310 and reducing the risk of breakage of the second wire 310; in addition, the size of the fillet is not too large, which is conducive to improving the slot fill factor of the stator slot 110. The radius of the fillet can be, but is not limited to, 0.37mm, 0.38mm, 0.39mm, 0.4mm, 0.41mm, 0.42mm and 0.43mm.

[0066] In some embodiments, the thickness of the insulator 320 ranges from 40μm to 60μm. In this way, the flat wire 300 is not too thick, which is conducive to making the flat wire 300 lightweight, shortening the heat dissipation path of the second wire 310 to the external environment, and quickly dissipating the heat of the second wire 310 to the external environment; in addition, the flat wire 300 is also not too thin, so that the insulator 320 is not easily broken down by high voltage when the flat wire 300 is energized. Exemplarily, the thickness of the insulator 320 can be, but is not limited to, 40μm, 50μm, 60μm. In some embodiments, the insulator 320 includes a plurality of second insulating layers 321, and the plurality of second insulating layers 321 are stacked along the thickness direction of the insulator 320. In some embodiments, the number of second insulating layers 321 ranges from 6 to 10. The number of second insulating layers 321 can be 6, 7, 8, 9 and 10.

[0067] In some embodiments, the material of the insulator 320 is configured as polyimide. However, the design is not limited thereto, and in some other embodiments, the material of the insulator 320 can also be polyurethane, which makes the mechanical strength of the insulator 320 high, and polyurethane has good mechanical properties, including high strength, wear resistance and tear resistance. This makes the flat wire 300 able to withstand greater physical stress, and also makes the electrical insulation performance of the insulator 320 good, polyurethane can effectively prevent current leakage, ensure the safe operation of the circuit, and the dielectric constant of polyurethane is relatively low, which is conducive to high-frequency signal transmission.

[0068] In a third aspect, the embodiments of the utility model provide a motor, the motor includes the stator, the stator adopts all technical schemes of above-mentioned all embodiments, therefore at least has all beneficial effects brought by technical scheme of above-mentioned embodiment, here will not repeat again. Can understand, the motor also includes the rotor that cooperates with the stator.

[0069] In a fourth aspect, the embodiments of the utility model provide a vehicle, the vehicle includes the motor, the motor adopts all technical schemes of above-mentioned all embodiments, therefore at least has all beneficial effects brought by technical scheme of above-mentioned embodiment, here will not repeat again.

[0070] The vehicle can be a fuel automobile, a plug-in hybrid electric vehicle, or a new energy vehicle, and the present disclosure does not make specific limitation thereto.

[0071] In the description of the present application, the terms "first", "second" are only used for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0072] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0073] The embodiments, implementation manners and related technical features of the present application can be combined or replaced with each other without conflict.

[0074] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification made to the above embodiment without departing from the technical solution of the present application and in accordance with the technical essence of the present application still falls within the scope of the technical solution of the present application.

Claims

1. A type of Leeds wire, characterized in that, include: The wire body includes a first conductor and a first insulating layer covering the outer periphery of the first conductor, wherein the first insulating layer is made of aluminum oxide.

2. The Lids line according to claim 1, characterized in that, The first conductor is made of aluminum.

3. The Litz wire according to claim 1, characterized in that, The thickness of the first insulating layer ranges from 10 μm to 30 μm.

4. The Litz wire according to claim 1, characterized in that, The line body is provided with multiple strands, and the Litz line also includes a connector that connects the multiple strands.

5. The Litz wire according to claim 4, characterized in that, The connector also covers the outer periphery of the multiple wires; And / or, the connector is provided with vents; And / or, the material of the connector is configured as an insulating material.

6. The Litz wire according to claim 1, characterized in that, The number of the lines ranges from 8 to 20; And / or, the diameter of the first wire is in the range of 0.5 mm to 0.6 mm.

7. The Lids line according to claim 1, characterized in that, The length of the cross-section of the Litz wire ranges from 2 mm to 3.5 mm; And / or, the width dimension of the cross section of the Litz line ranges from 1.4 mm to 2 mm.

8. A stator, characterized in that, include: The stator core is provided with stator slots; as well as The Litz wire as described in any one of claims 1 to 7 is disposed in the stator slot.

9. The stator according to claim 8, characterized in that, The stator also includes flat wires disposed in the stator slots.

10. The stator according to claim 9, characterized in that, In the same stator slot, the Litz wire is closer to the opening of the corresponding stator slot than the flat wire.

11. The stator according to claim 10, characterized in that, In the same stator slot, there are multiple Litz wires and multiple flat wires, and the multiple Litz wires and multiple flat wires are arranged sequentially along the slot depth direction of the corresponding stator slot.

12. The stator according to claim 9, characterized in that, The flat wire includes a second conductor and an insulator covering the second conductor, wherein the second conductor is made of copper or aluminum.

13. The stator according to claim 12, characterized in that, The length of the cross-section of the second conductor ranges from 2 mm to 3.5 mm; And / or, the width dimension of the cross-section of the second conductor ranges from 1.4 mm to 2 mm; And / or, the cross-section of the second conductor has rounded corners, the radius of which ranges from 0.37 mm to 0.43 mm.

14. The stator according to claim 12, characterized in that, The thickness of the insulator ranges from 40 μm to 60 μm.

15. An electric motor, characterized in that, Includes the stator as described in any one of claims 8 to 14.

16. A vehicle, characterized in that, Including the motor as described in claim 15.

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