Flat wire motor, motor shell processing method and flat wire winding processing method
By setting cooling channels inside the motor housing and stator core and using additive manufacturing to form a single unit, the problems of increased volume and maintenance difficulty in cooling flat wire motors are solved, achieving better cooling effect and reduced manufacturing difficulty.
Patent Information
- Application Number
- CN202411414650.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-11
- Publication Date
- 2025-11-07
AI Technical Summary
The existing cooling methods for flat wire motors increase the size of the motor and the difficulty of maintenance, and are also highly complex to manufacture, making it difficult to meet the requirements of equipment compactness.
Cooling channels are set inside the motor housing and stator core, and the motor housing, stator core and flat wire windings are integrally formed by additive manufacturing. Non-contact cooling medium circulation is adopted to avoid direct contact between the cooling medium and the windings.
It improves cooling efficiency, reduces manufacturing difficulty and cost, and also reduces problems such as oil leakage and maintenance difficulties, meeting the requirements for equipment compactness.
Smart Images
Figure CN120915040A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of flat wire motor, and particularly relates to a flat wire motor, a motor shell processing method and a flat wire winding processing method. BACKGROUND
[0002] In recent years, flat wire motors have been widely used in various fields such as aerospace, automobiles, household appliances and precision instruments. With the advancement of technology, the design and manufacturing process of flat wire motors have been continuously improved, which has significantly improved their performance and application range. However, due to the current limitations of forming process and cost, there are still problems such as manufacturing complexity and cooling difficulty in the design and manufacturing of flat wire motors.
[0003] Traditional motor windings are usually cooled by oil cooling or air cooling. This cooling method not only increases the overall volume of the flat wire motor by adding external air cooling or oil cooling devices, which does not meet the current trend of compact equipment, but also increases the design cost of the motor's anti-permeation device by directly contacting the cooling oil with the coil, which also causes the motor to be difficult to maintain and repair. SUMMARY
[0004] The present application provides a flat wire motor, a motor shell processing method and a flat wire winding processing method, which aims to reduce the manufacturing difficulty of flat wire motors while improving the cooling effect.
[0005] To achieve the above-mentioned purpose, the present application provides a flat wire motor, which comprises a motor shell, a stator core and a flat wire winding, the stator core comprises a winding slot, and the flat wire winding is embedded in the winding slot; a shell cooling channel is formed in the inner wall of the motor shell; and / or an iron core cooling channel is formed in the inner part of the stator core; at least one of the motor shell, the stator core and the flat wire winding is integrally formed.
[0006] As an optional solution of the flat wire motor, the stator core comprises a plurality of iron core pieces which are sequentially stacked and fixedly connected along the axial direction of the flat wire motor, at least a part of the adjacent iron core pieces are provided with an iron core cooling through hole, and the iron core cooling through holes are sequentially connected to form the iron core cooling channel.
[0007] As an optional solution of the flat wire motor, the outer diameter of the stator core is 5mm-1000mm; and / or the thickness of the iron core piece is 0.1mm-2mm.
[0008] As an optional solution of the flat wire motor, at least one of the motor shell, the stator core and the flat wire winding is integrally formed by additive manufacturing.
[0009] As an optional solution of the flat wire motor, the motor shell is provided with a shell cooling inlet and a shell cooling outlet, both of which are in communication with the shell cooling channel, and both of which are arranged on the outer side of the motor shell; and / or, the stator core comprises a yoke portion and a tooth portion connected to the yoke portion; the stator core is provided with a core cooling inlet and a core cooling outlet, both of which are in communication with the core cooling channel, and both of which are arranged on the yoke portion of the stator core.
[0010] As an optional solution of the flat wire motor, the core cooling channel comprises: a first cooling channel arranged in the yoke portion; and a second cooling channel arranged at least partially in the tooth portion, and in communication with the first cooling channel.
[0011] As an optional solution of the flat wire motor, the motor shell is in interference fit with the stator core; and / or, the inner wall of the motor shell is further provided with a limiting portion, which is in abutment with the stator core in the axial direction of the stator core.
[0012] The application further provides a motor shell processing method for processing the motor shell of the flat wire motor, which comprises the following steps: forming the shell cooling channel inside the motor shell original piece by additive manufacturing to form the motor shell original piece; and performing preset heat treatment and preset post-treatment on the motor shell original piece to obtain the required motor shell.
[0013] As an optional solution of the motor shell processing method, before the motor shell original piece is manufactured by additive manufacturing, the following steps are further included: determining the shape and area of the cross section of the shell cooling channel, the axial extension direction of the shell cooling channel, and / or the spacing between the shell cooling channel and the outer peripheral wall of the motor shell, according to the corresponding heat field of the flat wire winding when the flat wire winding is operated under the rated operating condition and the limit operating condition.
[0014] The application further provides a flat wire winding processing method for processing the flat wire winding of the flat wire motor, which comprises a plurality of flat wire monomers, and the plurality of flat wire monomers are sequentially connected and arranged in a predetermined direction to form the flat wire winding; the flat wire winding processing method comprises the following steps: forming a flat wire monomer original piece or a flat wire winding original piece by additive manufacturing; performing preset heat treatment and preset post-treatment on the flat wire monomer original piece or the flat wire winding original piece to form a flat wire monomer processed piece or a flat wire winding processed piece; and performing insulation treatment on the flat wire monomer processed piece or the flat wire winding processed piece to obtain the required flat wire monomer or the flat wire winding.
[0015] Compared with the prior art, the application has the following advantages:
[0016] The flat wire motor, the motor shell processing method and the flat wire winding processing method of the present application have the advantages that the cooling effect is better than that of the prior art, the problems of oil leakage, large motor size and difficult maintenance in later period are reduced, at least one of the motor shell, the stator core and the flat wire winding is integrally formed, the manufacturing difficulty of the flat wire motor is greatly reduced, especially when the cooling channel is arranged in the motor shell and / or the stator core, the integrally formed structure is more conducive to the formation of the cooling channel and the reduction of the processing cost. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 It is a structure schematic view of the flat wire motor in the embodiment of the present application.
[0018] Figure 2 It is a sectional view of the flat wire motor in the embodiment of the present application.
[0019] Figure 3 It is a structure schematic view of the core cooling channel of the flat wire motor in the embodiment of the present application.
[0020] Figure 4 It is a structure schematic view of the spiral type equal-width cooling channel of the flat wire motor in the embodiment of the present application.
[0021] Figure 5 It is a structure schematic view of the circumferential type equal-width cooling channel of the flat wire motor in the embodiment of the present application.
[0022] Figure 6 It is a structure schematic view of the circumferential type widened full-coverage cooling channel with spoiler of the flat wire motor in the embodiment of the present application.
[0023] Figure 7 It is a structure schematic view of the circumferential type widened three-cooling-channel cooling channel with long spoiler of the flat wire motor in the embodiment of the present application.
[0024] Figure 8 It is a structure schematic view of the circumferential type widened three-cooling-channel cooling channel with long and short spoilers of the flat wire motor in the embodiment of the present application.
[0025] Figure 9 It is a structure schematic view of the axial type cooling channel of the flat wire motor in the embodiment of the present application.
[0026] Figure 10 It is a comparison chart of the maximum wall surface temperature of the five types of cooling channels of the flat wire motor in the embodiment of the present application.
[0027] Figure 11 It is a comparison chart of the pressure difference of the five types of cooling channels of the flat wire motor in the embodiment of the present application.
[0028] Figure 12A cloud chart of simulation analysis results of five cooling channels of the flat wire motor in the embodiment of the present application.
[0029] Figure 13 A flow chart of the motor shell processing method in the embodiment of the present application.
[0030] Figure 14 A flow chart of the first processing method of the flat wire winding in the embodiment of the present application.
[0031] Reference signs:
[0032] 10, flat wire motor; 1, motor shell; 11, shell cooling channel; 111, shell cooling inlet; 112, shell cooling outlet; 12, limiting part; 2, stator core; 2a, yoke part; 2b, tooth part; 21, core cooling channel; 211, first cooling channel; 212, second cooling channel; 22, core piece; 221, core cooling hole; 3, flat wire winding. DETAILED DESCRIPTION
[0033] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.
[0034] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.
[0035] It should be noted that: similar reference signs and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.
[0036] In the description of the application, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the application is usually placed, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application. In addition, the terms "first", "second", "third" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance. In the description of the application, the meaning of "a plurality of" is two or more, unless otherwise specified.
[0037] In the description of the application, it should be noted that, unless otherwise specified and limited, the terms "provided", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.
[0038] In the present application, unless otherwise specified and limited, "on" or "under" of the first feature to the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, "on", "above" and "above" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. "Below", "below" and "below" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.
[0039] The embodiments of the application are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary and are only used to explain the application, and cannot be understood as limiting the application.
[0040] Please refer to Figures 1-3 The present embodiment provides a flat wire motor, the flat wire motor 10 includes a motor shell 1 and a stator core 2 and a flat wire winding 3 which are arranged in the motor shell 1, the stator core 2 includes a winding slot, and the flat wire winding 3 is embedded in the winding slot. A shell cooling channel 11 is formed in the inner wall of the motor shell 1. A core cooling channel 21 is formed in the stator core 2.
[0041] The flat wire motor 10 of the embodiment has better cooling effect than the prior art by opening the cooling channels inside the motor housing 1 and the stator core 2, and reduces the problems of oil leakage, large motor size and difficult maintenance.
[0042] In an embodiment, the motor housing 1 further comprises a housing cooling inlet 111 and a housing cooling outlet 112, which are both in communication with the housing cooling channel 11. The housing cooling inlet 111 is used to introduce cooling medium into the housing cooling channel 11. The housing cooling outlet 112 is used to discharge the cooling medium in the housing cooling channel 11. The stator core 2 further comprises a core cooling inlet and a core cooling outlet, which are both in communication with the core cooling channel 21. The core cooling inlet is used to introduce cooling medium into the core cooling channel 21. The core cooling outlet is used to discharge the cooling medium in the core cooling channel 21.
[0043] In this way, the cooling medium in the housing cooling channel 11 and the core cooling channel 21 can circulate, further improving the cooling effect. Further, the housing cooling inlet 111, the housing cooling outlet 112, the core cooling inlet and the core cooling outlet are respectively connected with the cold source, without increasing the size of the flat wire motor 10 itself, and the cooling medium does not directly contact the flat wire winding 3, without increasing the difficulty of maintenance and repair.
[0044] In an embodiment, the housing cooling inlet 111 and the housing cooling outlet 112 are arranged on the outer side of the motor housing 1, which facilitates the connection of the housing cooling inlet 111 and the housing cooling outlet 112 with the cold source, and facilitates assembly and later maintenance.
[0045] It can be understood that the stator core 2 comprises a yoke portion 2a and a plurality of tooth portions 2b connected to the yoke portion 2a. The plurality of tooth portions 2b are circumferentially spaced apart, and a winding slot is formed between adjacent two tooth portions 2b.
[0046] In an embodiment, the core cooling inlet and the core cooling outlet are arranged on the yoke portion 2a of the stator core 2, which facilitates the connection of the core cooling inlet and the core cooling outlet with the cold source, facilitates assembly and later maintenance, and does not interfere with the flat wire winding 3.
[0047] In an embodiment, the yoke portion 2a is internally provided with a first cooling channel 211. Further, at least part of the tooth portion 2b is internally provided with a second cooling channel 212, which is in communication with the first cooling channel 211 and forms the core cooling channel 21. In this way, the cooling liquid can circulate in the first cooling channel 211 and the second cooling channel 212, and the flat wire winding 3 can be sufficiently cooled, with better cooling effect.
[0048] In an embodiment, the motor housing 1 is in interference fit with the stator core 2, thereby avoiding axial movement, circumferential rotation or shaking of the flat wire winding 3 along the axial direction of the flat wire motor 10, improving the installation stability of the flat wire winding 3, and thereby facilitating improvement of the performance of the flat wire motor 10.
[0049] It should be noted that the interference fit means that, during assembly, the cavity inner diameter of the motor housing 1 is increased by the elasticity of the material of the motor housing 1 itself, and then the stator core 2 is assembled into the cavity of the motor housing 1. When the cavity inner diameter of the motor housing 1 returns to normal, the inner wall of the motor housing 1 generates a clamping force on the stator core 2, so as to connect the motor housing 1 and the stator core 2 in a fitting manner.
[0050] In an embodiment, the motor housing 1 further comprises a limiting portion 12, which abuts against the stator core 2 along the axial direction of the stator core 2, thereby avoiding axial movement of the stator core 2 along the axial direction of the flat wire motor 10, improving the installation stability of the stator core 2, and thereby facilitating improvement of the performance of the flat wire motor 10.
[0051] In an embodiment, the diameter of the circumscribed circle of the cross section of the shell cooling channel 11 is 0.5-50mm. The limitation of the diameter of the circumscribed circle of the cross section of the shell cooling channel 11 can take into account the structural strength of the motor housing 1 and the cooling effect of the shell cooling channel 11; the cross section of the shell cooling channel 11 is a cross section perpendicular to the axis of the shell cooling channel 11.
[0052] For example, the diameter of the circumscribed circle of the cross section of the shell cooling channel 11 can be any value between 0.5mm and 50mm, such as 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, etc.
[0053] Preferably, in the specific embodiments of the present application, the diameter of the circumscribed circle of the cross section of the shell cooling channel 11 is 1-30mm, which improves the structural strength of the motor housing 1 while ensuring the cooling effect of the shell cooling channel 11.
[0054] In an embodiment, the shape of the cross section of the shell cooling channel 11 is circular, elliptical, drop-shaped, gourd-shaped, square, rectangular, polygonal or irregular circular arc, which is not limited here and can be selected as needed. It should be noted that the irregular circular arc is formed by connecting a plurality of circular arcs with different radii in sequence.
[0055] Preferably, the shape of the cross section of the shell cooling channel 11 is circular, elliptical, drop-shaped or irregular circular arc, which has better cooling effect.
[0056] In an embodiment, the cross-sectional area of the shell cooling channel 11 is constant along the extension direction of the axis of the shell cooling channel 11. Of course, the cross-sectional area of the shell cooling channel 11 can also be set to vary according to a preset rule or irregularly along the extension direction of the axis of the shell cooling channel 11, which is not limited herein and can be selected as required.
[0057] Specifically, in the specific embodiments of the present application, the shape of the cross section of the shell cooling channel 11 varies according to a preset rule or irregularly along the extension direction of the axis of the shell cooling channel 11, and further, the diameter of the circumscribed circle of the cross section of the shell cooling channel 11 is 1 mm-10 mm, in other words, the cross-sectional area of the cross section of the shell cooling channel 11 at any position along the extension direction of the axis of the shell cooling channel 11 is at most 10 mm and at least 1 mm.
[0058] Please refer to Figures 4-8 In an embodiment, the axis of the shell cooling channel 11 is a spiral line or a U-shaped line, which is not limited herein and can be selected as required.
[0059] By limiting the extension direction of the axis of the shell cooling channel 11 and the variation of the cross-sectional area of the shell cooling channel 11, the flow rate of the cooling medium at different positions in the shell cooling channel 11 can be adjusted, the overall heat exchange efficiency of the flat wire motor 10 is improved, and the heat distribution of the flat wire motor 10 is more uniform.
[0060] In an embodiment, the diameter of the circumscribed circle of the cross section of the core cooling channel 21 is 0.5 mm-50 mm. The limitation of the diameter of the circumscribed circle of the cross section of the core cooling channel 21 can take into account the structural strength of the stator core 2 and the cooling effect of the core cooling channel 21; the cross section of the core cooling channel 21 is a cross section perpendicular to the axis of the core cooling channel 21.
[0061] It should be noted that the cross section of the first cooling channel 211 is a cross section perpendicular to the axis of the first cooling channel 211; the cross section of the second cooling channel 212 is a cross section perpendicular to the axis of the second cooling channel 212; the areas of the cross sections of the first cooling channel 211 and the second cooling channel 212 can be the same or different; the shapes of the cross sections of the first cooling channel 211 and the second cooling channel 212 can be the same or different, which is not limited herein.
[0062] For example, the diameter of the circumscribed circle of the cross section of the core cooling channel 21 can be any value between 0.5 mm and 50 mm, such as 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, etc.
[0063] Preferably, in the specific embodiments of the present application, the circumscribed circle diameter of the cross section of the core cooling channel 21 is 1-30 mm, which improves the structural strength of the stator core 2 while ensuring the cooling effect of the core cooling channel 21.
[0064] In an embodiment, the shape of the cross section of the core cooling channel 21 is circular, elliptical, drop-shaped, gourd-shaped, square, rectangular, polygonal, or irregular circular arc, which is not limited here and can be selected as required.
[0065] Preferably, the shape of the cross section of the core cooling channel 21 is circular, elliptical, drop-shaped, or irregular circular arc, which has a better cooling effect.
[0066] It should be noted that the shape of the cross section of the shell cooling channel 11 can be the same as that of the core cooling channel 21, which is convenient for design and manufacture; of course, the shape of the cross section of the shell cooling channel 11 can also be different from that of the core cooling channel 21, so that the motor shell 1 and the stator core 2 obtain different cooling effects, which is beneficial to expand the application range of the flat wire motor 10.
[0067] In an embodiment, the area of the cross section of the core cooling channel 21 does not change along the extension direction of the axis of the core cooling channel 21. Of course, it can also be provided that the area of the cross section of the core cooling channel 21 changes according to a predetermined rule or irregularly along the extension direction of the axis of the core cooling channel 21, which is not limited here and can be selected as required.
[0068] Specifically, in the specific embodiments of the present application, the shape of the cross section of the core cooling channel 21 changes according to a predetermined rule or irregularly along the extension direction of the axis of the core cooling channel 21, and further, the circumscribed circle diameter of the cross section of the core cooling channel 21 is 1-10 mm, in other words, the area of the cross section of the core cooling channel 21 at any position along the extension direction of the axis of the core cooling channel 21 is at most 10 mm and at least 1 mm.
[0069] It should be noted that the shape of the cross section of the shell cooling channel 11 can be the same as that of the core cooling channel 21, or different, which is not limited here.
[0070] Correspondingly, in an embodiment, the axis of the core cooling channel 21 can also be a spiral line or a U-shaped line, which is not limited here and can be selected as required.
[0071] By limiting the extension direction of the iron core cooling channel 21 axis and the area variation of the cross section of the iron core cooling channel 21, the flow rate of the cooling medium at different positions in the iron core cooling channel 21 can be adjusted, the overall heat exchange efficiency of the flat wire motor 10 is improved, and the heat distribution of the flat wire motor 10 is more uniform.
[0072] In an embodiment, the outer diameter of the stator core 2 is 5mm-1000mm. By limiting the outer diameter of the stator core 2, different design and application requirements are met to expand the application range of the flat wire motor 10.
[0073] Exemplarily, the outer diameter of the stator core 2 can be any value between 5mm-1000mm, such as 5mm, 16mm, 80mm, 180mm, 300mm, 380mm, 600mm, 850mm, 950mm, 1000mm, etc.
[0074] Preferably, the outer diameter of the stator core 2 is 5mm-600mm, which is small in size and easy to process by additive manufacturing.
[0075] Please continue to combine Figures 1-3 In the embodiment, the stator core 2 includes a plurality of iron core pieces 22 which are sequentially stacked and fixedly connected along the axial direction of the flat wire motor 10, and at least part of the adjacent iron core pieces 22 are provided with iron core cooling through holes 221, and all the iron core cooling through holes 221 are sequentially communicated and form the iron core cooling channel 21.
[0076] Specifically, in the embodiment, the iron core piece 22 is a silicon steel sheet.
[0077] It should be noted that the additive formed silicon steel sheet can eliminate the mold opening cost of the silicon steel sheet, and additive forming also makes it possible to form a cooling flow channel inside the stator core 2 composed of silicon steel sheets.
[0078] It can be understood that when the cross-sectional area of the iron core cooling channel 21 changes according to a predetermined rule or irregularly along the extension direction of the iron core cooling channel 21 axis, the shapes of the iron core cooling through holes 221 of at least part of the iron core pieces 22 are different.
[0079] In an embodiment, the thickness of the iron core piece 22 is 0.1mm-2mm. By limiting the thickness of the iron core piece 22, different design and application requirements are met to expand the application range of the flat wire motor 10.
[0080] Exemplarily, the thickness of the iron core piece 22 can be any value between 0.1mm-2mm, such as 0.1mm, 0.3mm, 0.5mm, 0.8mm, 0.9mm, 1.3mm, 1.7mm, 1.9mm, 2mm, etc.
[0081] Preferably, the thickness of the core piece 22 is 0.2mm-1mm, which is moderate in size and easy to process by additive manufacturing.
[0082] It should be noted that the shape and size of the motor housing 1 can be customized according to the shape and assembly position of the power assembly, so that the motor housing 1 can adapt to different power assemblies and have a wider application range.
[0083] Further, in the case that the power assembly is designed to be compact and the volume and mass of the flat wire motor 10 are strictly required, a weight-reducing structure such as a groove or a through hole can be arranged on the motor housing 1 through optimization and dot matrix design, so as to further reduce the space volume and mass of the motor housing 1 under the premise of ensuring that the motor housing 1 matches the power assembly, and thus the purpose of lightweight of the power assembly is achieved.
[0084] It should be noted that in the embodiment, the yoke part 2a of the motor housing 1 and the stator core 2 is in a ring structure, and the shape design idea of the shell cooling channel 11 and the first cooling channel 211 is the same. The shape of the second cooling channel 212 corresponds to the shape of the tooth part 2b, and the axis of the second cooling channel 212 can be an S-shaped line, a U-shaped line or a straight line.
[0085] Please refer to Figures 1-9 , wherein Figures 4 to 9 is a structural schematic diagram of cooling channels of different shapes (including the shell cooling channel 11 and the first cooling channel 211), and the following will take the motor housing 1 and the shell cooling channel 11 as an example to introduce the design process and simulation results of the structure of the cooling channel of different shapes as shown in Figures 4 to 9 .
[0086] First, theoretical calculation is performed.
[0087] It should be noted that the cooling channel is generally divided into spiral type, circumferential type and axial type, and under the premise that the pressure loss of the shell cooling channel 11 is not considered, the cooling effect is in the order of axial type, spiral type and circumferential type from good to poor. In the case that the maximum temperature of the flat wire motor 10 is the same, the tube flow pressure drop of the spiral type is the smallest, the circumferential type is the second, and the tube flow pressure drop of the axial type is the largest. Therefore, the design of the cooling channel needs to consider the requirements of the cooling effect and the pressure drop.
[0088] The flat wire motor 10 cooled by the above-mentioned cooling channel in a water cooling manner mainly dissipates heat through the convection heat exchange process between the cooling channel and the flat wire motor 10. The convection heat exchange refers to the heat exchange process between the moving fluid (i.e. the above-mentioned cooling medium) and the solid surface through which it flows. According to Newton's cooling law, the heat of convection heat exchange is proportional to the convection heat exchange coefficient, the heat exchange area and the temperature difference between the wall and the cooling channel:
[0089] φ=h f A(Tw -T f );
[0090] φ is the heat exchange power, h f is the convective heat transfer coefficient, A is the coolant heat exchange area, T w is the coolant side wall temperature, T f is the coolant temperature.
[0091] The convective heat transfer coefficient reflects the strength of the convective heat transfer capacity, and is related to many factors affecting the heat exchange process, including the causes and flow state of convective motion, the physical properties of the fluid (which vary with species, temperature and pressure), the shape, size and relative position of the heat transfer surface, etc. According to the Gnileinski formula, it is calculated as follows:
[0092]
[0093] R e is the Reynolds number, P r is the Prandtl number, d is the characteristic diameter, and l is the cooling length.
[0094] The size of the pipe flow pressure drop determines the size of the required water pump power, and has an important influence on the design of the cooling channel. The pipe flow pressure drop is caused by the resistance of the cooling channel. In the calculation process, the resistance of the cooling channel is divided into the resistance along the path and the local resistance:
[0095] ΔP=P f +P j ;
[0096]
[0097] wherein P f is the pressure loss along the path, P j is the local pressure loss, ξ, is the corresponding resistance coefficient, v is the coolant velocity, and g is the acceleration of gravity.
[0098] Under the condition that the inner side wall temperature of the shell is set to 120℃, the basic parameters such as the width, height and total length of the cooling channel of the embodiment are set, and the heat exchange efficiency of the cooling channel and the cooling structure of the prior art is compared according to the heat transfer calculation, and the results are shown in the following table:
[0099] Prior art cooling structure Cooling channel of the embodiment Cooling channel height mm 7 7 Cooling channel width mm 41 25 Cooling channel length mm 2000 2960 Inlet flow L / min 8 8 Motor current A 220 220 Motor voltage V 350 350 Heat exchange power W 5236 7315 Coolant outlet temperature °C 76.22 80.13 along Pressure losses kPa ]] 0.73059 2.873115
[0100] According to the design parameters of the cooling channel of the embodiment, the corresponding spiral, circumferential and circumferential with flow sheet type cooling channel models are established, the axial type is excluded because of excessive pressure loss, and the heat exchange power and pressure loss of the three are sorted as follows: spiral < circumferential < circumferential with flow sheet type.
[0101] Then, the design analysis is performed.
[0102] Based on theoretical calculation and initial test, seven representative model schemes are designed according to spiral and circumferential type.
[0103] The initial design is an equal-width channel. Due to the limitation of the position of the channel inlet and outlet, the spiral and circumferential equal-width channels cannot cover the entire area of the motor shell. In order to optimize the equal-width channel, the channel is partially widened to cover the entire area and avoid local overheating of the motor shell. The widened full-coverage channel scheme is obtained. After simulation, it is found that after the channel is widened, there is a sudden change in the cross section of the channel, which is easy to cause small-range overheating and low overall heat exchange efficiency of the widened channel. Therefore, the rib (i.e. spoiler) design is adopted to improve the heat exchange efficiency.
[0104] However, the addition of ribs to the spiral channel is very difficult in design and additive manufacturing. Therefore, the main focus is on adding ribs to the circumferential channel.
[0105] The above-mentioned schemes and final naming are shown in the following table:
[0106]
[0107] Through analysis, it is found that the main factors affecting heat exchange and pressure difference are:
[0108] a) Channel type: spiral or circumferential, under the condition that the cross-sectional area and length of the cooling channel are equal, and other boundary conditions are the same, the spiral channel has higher heat exchange efficiency and smaller pressure difference;
[0109] b) Channel cross-sectional area: under the condition that all other parameters are consistent and the flow rate is constant, the larger the cross-sectional area of the channel, the smaller the flow resistance, and therefore the smaller the pressure difference, but the heat exchange efficiency will also be relatively reduced;
[0110] c) Channel length: under the condition that all other parameters are consistent and the flow rate is constant, the longer the cooling channel, the better the heat exchange effect, but the pressure difference will increase;
[0111] d) Ribs: in the presence of ribs, the pressure difference will increase; but with reasonable rib size, length and position, the heat exchange efficiency will be improved.
[0112] After screening the above schemes, considering heat exchange and pressure difference, the S-simple and U-simple schemes are abandoned. Also, the U-wide-spoiler scheme has too dispersed rib design, which will cause more turbulence inside the channel, so it is not considered.
[0113] Finally, S-wide, U-wide, U-wide-2 channel-spoiler and U-wide-3 channel-spoiler were selected for simulation, in which the three-channel spoiler in U-wide-3 channel-spoiler was divided into long type (denoted as U-wide-3 channel-spoiler-1) and long-short type combination (denoted as U-wide-3 channel-spoiler-2).
[0114] Finally, simulation was carried out.
[0115] Please refer to Figure 10 and Figure 11 , respectively, the selected five cooling channel structures were simulated and analyzed, and the highest wall temperature and pressure difference were obtained. It can be seen that for the circumferential type (U) cooling channel, the two-channel structure (U-wide-2 channel-spoiler) has the best heat transfer effect due to small change in coolant flow area, uniform flow velocity and small local high temperature area. The ribbed structure (U-wide-2 channel-spoiler, U-wide-3 channel-spoiler-1 and U-wide-3 channel-spoiler-2) has a pressure difference increase of 2.2 kPa at 8 L / min flow rate and 5 kPa at 12 L / min flow rate compared with the non-ribbed structure (U-wide).
[0116] S-wide has smaller pressure difference than the ribbed structure (U-wide-2 channel-spoiler, U-wide-3 channel-spoiler-1 and U-wide-3 channel-spoiler-2) of U-type channel, but the heat transfer effect is worse than U-wide-2 channel-spoiler. S-wide has larger pressure difference than U-wide due to the increase in actual flow path length, but for 8 L / min cooling flow rate, the highest wall temperature is reduced by about 5 K, and the heat transfer effect is better.
[0117] Please refer to Figure 1 and Figure 12 , the temperature distribution of each cooling channel is shown by different colors, in which the top of the temperature bar is red and the bottom is blue, red represents high temperature and blue represents low temperature, the closer the color to red, the higher the temperature, and the closer the color to blue, the lower the temperature. It can be seen that the temperature distribution of U-wide-2 channel-spoiler is more uniform. The along-path loss and local flow resistance of the ribbed structure are greater than those of the non-ribbed structure, but the two-channel and three-channel structures have little effect on the pressure difference.
[0118] In summary, the heat exchange effect of U-wide-2 channel-spoiler is the best. However, the heat exchange effects of S-wide and U-wide are also good while keeping the pressure difference relatively small.
[0119] In the embodiment, the motor housing 1 is integrally formed by additive manufacturing, that is, when the motor housing 1 is manufactured by additive manufacturing, the shell cooling channel 11 inside the shell wall is also formed synchronously.
[0120] In an embodiment, the motor housing 1 is integrally formed by additive manufacturing such as laser powder bed fusion, electron beam powder bed fusion, binder jetting, or cold spraying.
[0121] Please refer to Figure 1 , Figure 2 , and Figure 13 The embodiment also provides a motor housing processing method for processing the motor housing 1 as described above; the motor housing processing method comprises the following steps:
[0122] S11, forming a motor housing original piece by additive manufacturing, and forming a shell cooling channel inside the motor housing original piece;
[0123] S12, performing preset heat treatment and preset post-treatment on the motor housing original piece to obtain a required motor housing.
[0124] It can be understood that the motor housing 1 is integrally formed by additive manufacturing, which not only reduces the manufacturing difficulty, but also facilitates the formation of the shell cooling channel 11, is easy to process irregular shell cooling channels 11, and reduces the processing cost.
[0125] It should be noted that the specific operation steps of the preset heat treatment and the preset post-treatment in step S12 are prior art, which will not be described here.
[0126] Specifically, in the embodiment, step S11 comprises the following steps:
[0127] S111, converting a three-dimensional model of the motor housing into slice data containing height information and profile information of a cross section of the motor housing corresponding to different heights;
[0128] It should be noted that the height in step S111 is the height of the motor housing 1 along the axial direction of the flat wire motor 10, and the cross section of the motor housing 1 is a cross section perpendicular to the axial direction of the flat wire motor 10.
[0129] S112, using a laser powder bed melting, electron beam powder bed melting or binder jetting forming process, taking metal powder, ceramic powder or composite material powder as the shell raw material, layer by layer laying the shell raw material on the powder bed and sintering or bonding the shell raw material to form the profile of the motor shell cross section corresponding to different heights, and then making the motor shell raw piece, and the shell cooling channel is formed inside the shell wall of the motor shell raw piece.
[0130] Of course, in other embodiments, step S112 can also be:
[0131] Using a cold spraying process, taking metal powder or composite material powder as the shell raw material, using a high-speed spray gun to spray the shell raw material, and adjusting the shell raw material spraying amount, the position and angle of the high-speed spray gun, the cold spraying time and other parameters, so that the shell raw material is stacked layer by layer according to the slice data, to form the profile of the motor shell cross section corresponding to different heights.
[0132] It should be noted that the metal powder, ceramic powder or composite material powder all use materials in the prior art.
[0133] In an embodiment, before step S111, the following steps are further included:
[0134] According to the heat field corresponding to the operation of the flat wire winding under rated operating conditions and extreme operating conditions, the shape of the shell cooling channel cross section, the area of the shell cooling channel cross section, the axial extension direction of the shell cooling channel and / or the spacing between the shell cooling channel and the outer peripheral wall of the motor shell are determined.
[0135] Any one of the shape of the cross section of the shell cooling channel 11, the area of the cross section of the shell cooling channel 11, the axial extension direction of the shell cooling channel 11 and the spacing between the shell cooling channel 11 and the outer peripheral wall of the motor shell 1 can be determined according to the heat field corresponding to the operation of the flat wire winding 3 under rated operating conditions and extreme operating conditions, to ensure the cooling effect of the shell cooling channel 11.
[0136] It should be noted that by controlling the spacing between the shell cooling channel 11 and the outer peripheral wall of the motor shell 1, and the spacing between the core cooling channel 21 and the outer peripheral wall of the stator core 2, the purpose of controlling the spacing between the shell cooling channel 11 and the core cooling channel 21 along the radial direction of the flat wire motor 10 can be achieved, and the cooling effect of the whole flat wire motor 10 can be adjusted.
[0137] In the embodiment, the plurality of core pieces 22 of the stator core 2 are integrally formed by additive manufacturing, in other words, when the core pieces 22 are manufactured by additive manufacturing, the core cooling holes 221 on the core pieces 22 are also formed synchronously. Of course, in other embodiments, the stator core 2 can also be integrally formed by additive manufacturing, in other words, when the stator core 2 is manufactured by additive manufacturing, the core cooling channels 21 inside the stator core 2 are also formed synchronously.
[0138] In an embodiment, the stator core 2 is integrally formed by additive manufacturing such as laser powder bed fusion, electron beam powder bed fusion, binder jetting, or cold spray.
[0139] In the embodiment, the flat wire winding 3 is integrally formed by additive manufacturing. Alternatively, the flat wire winding 3 is integrally formed by additive manufacturing such as laser powder bed fusion, electron beam powder bed fusion, binder jetting, or cold spray.
[0140] Please refer to Figure 1 , Figure 2 and Figure 14 , the embodiment also provides a flat wire winding processing method for processing the flat wire winding 3 as described above, the flat wire winding processing method comprising the following steps:
[0141] S31, forming a flat wire winding original piece by additive manufacturing;
[0142] S32, performing preset heat treatment and preset post-treatment on the flat wire winding original piece to obtain a flat wire winding processed piece;
[0143] S33, performing insulation treatment on the flat wire winding processed piece to obtain a required flat wire winding.
[0144] The flat wire winding 3 is integrally formed by additive manufacturing, which is convenient for manufacturing a small-size flat wire winding 3 and can avoid damage to the flat wire during winding.
[0145] It should be noted that the specific operation steps of the preset heat treatment and the preset post-treatment in step S32 and the insulation treatment in step S33 are prior art and will not be described here.
[0146] In the embodiment, the motor housing 1, the stator core 2, and the flat wire winding 3 are integrally formed by additive manufacturing, which greatly reduces the manufacturing difficulty of the flat wire motor 10, especially the cooling channels in the motor housing 1 and the stator core 2, which are processed by additive manufacturing, are more conducive to the formation of the cooling channels and reduce the processing cost.
[0147] Exemplarily, the cross section of the shell cooling channel 11 is a circular ring, which is a cross section perpendicular to the axial direction of the flat wire motor 10; the area of the longitudinal section of the core cooling channel 21 first increases and then decreases from top to bottom along the axial direction of the flat wire motor 10, and the longitudinal section of the core cooling channel 21 is a cross section parallel to the axial direction of the flat wire motor 10.
[0148] In an embodiment, the flat wire winding 3 comprises a plurality of flat wire units, which are sequentially connected along a preset direction and are arranged to form the flat wire winding 3; the flat wire units are integrally formed by additive manufacturing.
[0149] Please combine Figure 1 and Figure 2 In an embodiment, the flat wire winding processing method comprises the following steps:
[0150] S301, forming a flat wire unit original piece by additive manufacturing;
[0151] S302, performing preset heat treatment and preset post-treatment on the flat wire unit original piece to obtain a flat wire unit processed piece;
[0152] S303, performing insulation treatment on the flat wire unit processed piece to obtain a required flat wire unit finished product;
[0153] S304, performing wire insertion, twisting, welding and insulation treatment on the flat wire unit finished product in the winding slot to obtain a required flat wire winding finished product.
[0154] The flat wire units are integrally formed by additive manufacturing, which is convenient for manufacturing small-size flat wire units.
[0155] It should be noted that the specific operation steps of the preset heat treatment and the preset post-treatment in step S302, the insulation treatment in step S303 and the wire insertion, twisting, welding and insulation treatment in step S304 are prior art, which will not be described here.
[0156] In an embodiment, the motor housing 1, the stator core 2 and the flat wire winding 3 are integrally formed by additive manufacturing. For the convenience of description, the whole integrally formed by the motor housing 1, the stator core 2 and the flat wire winding 3 is referred to as a motor stator integrated piece.
[0157] Exemplarily, please combine Figure 1 and Figure 2 The processing method of the motor stator integrated piece comprises the following steps:
[0158] S41, splitting the three-dimensional model of the motor stator integrated piece into a motor housing data model, a stator core data model and a flat wire winding data model;
[0159] S42, in the stator core data model, a thin layer of a first preset thickness on each side of the silicon steel sheet is taken as a core insulation layer; in the flat wire winding data model, a thin layer of a second preset thickness on the outer side of the flat wire monomer is taken as a flat wire insulation layer; and the core insulation layer and the flat wire insulation layer are taken as an insulation layer data model;
[0160] S43, slice the motor housing data model, the stator core data model, the flat wire winding data model and the insulation layer data model with a preset layer thickness to form a plurality of motor stator integrated part slice data containing the outlines of the motor housing data model, the stator core data model, the flat wire winding data model and the insulation layer data model corresponding to different heights;
[0161] S44, according to the plurality of motor stator integrated part slice data, determine the type of raw material, the powder spraying parameters of the nozzle, and the liquid spraying parameters of the binder or insulating material nozzle;
[0162] It should be noted that the motor housing 1 data model, the stator core 2 data model, the flat wire winding 3 data model and the insulation layer data model respectively adopt different raw materials, for example, the motor housing 1 adopts titanium alloy, the brand is TC4; the stator core 2 adopts silicon steel containing 2.1% of silicon; the flat wire winding 3 adopts pure copper. The insulation layer adopts the insulating material in the prior art; of course, the motor housing 1, the stator core 2 and the flat wire winding 3 can also adopt other materials in the prior art, which are not limited here.
[0163] S45, using a position-adjustable matrix nozzle, layer by layer laying the corresponding raw material according to the preset layer thickness, and different materials corresponding to different data models are sprayed to specific positions using different groups of nozzles, and then compacting and heating are performed using compacting and heating rollers;
[0164] S46, the forming platform is lowered by one layer, and steps S41-S45 are repeated until the motor stator integrated part forming part is obtained;
[0165] S47, heat treatment and post-processing are performed on the motor stator integrated part forming part to obtain the motor stator integrated part finished product.
[0166] It should be noted that in the same additive manufacturing equipment, different materials are used to synchronously and integrally form the motor housing 1, the stator core 2 and the flat wire winding 3, which can effectively reduce the assembly process of the flat wire motor 10 and reduce the equipment investment and labor cost of the flat wire motor 10 production line.
[0167] Note that the above merely describes preferred embodiments of the present application and the principles of the technology applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various obvious changes, modifications and substitutions can be made without departing from the scope of the present application. Therefore, although the present application has been described in detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the claims.
Claims
1. Flat wire motor, characterized in that The motor shell (1) and the stator core (2) and the flat wire winding (3) arranged in the motor shell (1) are arranged in the motor shell (1), the stator core (2) comprises a winding slot, and the flat wire winding (3) is embedded in the winding slot; The shell wall of the motor shell (1) is internally provided with a shell cooling channel (11); and / or, the stator core (2) is internally provided with a core cooling channel (21); At least one of the motor shell (1), the stator core (2) and the flat wire winding (3) is integrally formed.
2. The flat wire motor according to claim 1, characterized in that The stator core (2) comprises a plurality of core pieces (22) which are sequentially stacked and fixedly connected along the axial direction of the flat wire motor (10), at least part of the adjacent core pieces (22) are provided with core cooling through holes (221), and the core cooling through holes (221) are sequentially communicated to form the core cooling channel (21).
3. The flat wire motor of claim 2, wherein The outer diameter of the stator core (2) is 5mm-1000mm; and / or, The thickness of the core piece (22) is 0.1mm-2mm.
4. The flat wire motor of claim 1, wherein At least one of the motor shell (1), the stator core (2) and the flat wire winding (3) is integrally formed by additive manufacturing.
5. The flat wire motor of claim 1, wherein The motor shell (1) is provided with a shell cooling inlet (111) and a shell cooling outlet (112) which are in communication with the shell cooling channel (11), and the shell cooling inlet (111) and the shell cooling outlet (112) are arranged on the outer side of the motor shell (1); and / or, The stator core (2) comprises a yoke portion (2a) and a tooth portion (2b) connected to the yoke portion; the stator core (2) is provided with a core cooling inlet and a core cooling outlet which are in communication with the core cooling channel (21), and the core cooling inlet and the core cooling outlet are arranged on the yoke portion (2a) of the stator core (2).
6. The flat wire motor of claim 5, wherein The core cooling channel (21) comprises: A first cooling channel (211) is arranged in the yoke portion (2a); A second cooling channel (212) is arranged in at least part of the tooth portion (2b), and the second cooling channel (212) is in communication with the first cooling channel (211).
7. Flat wire motor according to any of claims 1-6, characterized in that The motor shell (1) and the stator core (2) are in interference fit; and / or, The inner wall of the motor shell (1) is further provided with a limiting portion (12), and the limiting portion (12) is in abutment with the stator core (2) along the axial direction of the stator core (2).
8. A method of processing an electrical machine housing, characterized by A motor shell for processing a flat wire motor as claimed in any one of claims 1-7, the motor shell processing method comprising the following steps: An original motor shell is formed by additive manufacturing, and the shell cooling channel is formed in the original motor shell; The original motor shell is subjected to preset heat treatment and preset post-treatment to obtain a required motor shell.
9. The motor housing machining method according to claim 8, characterized by, Before the original motor shell is manufactured by additive manufacturing, the following steps are further included: The shape and area of the cross section of the shell cooling channel, the axial extension direction of the shell cooling channel and / or the spacing between the shell cooling channel and the outer peripheral wall of the motor shell are determined according to the corresponding heat field of the flat wire winding when the flat wire winding is operated under rated operating conditions and extreme operating conditions.
10. A method of processing a flat conductor winding, characterized by The flat wire winding for processing the flat wire motor as claimed in any one of claims 1-7 comprises a plurality of flat wire elements, and the plurality of flat wire elements are sequentially connected along a preset direction and are wound to form the flat wire winding; the processing method of the flat wire winding comprises the following steps: The flat wire element or the flat wire winding element is formed by additive manufacturing; The flat wire element or the flat wire winding element is subjected to preset heat treatment and preset post-treatment to form a flat wire element processed product or a flat wire winding processed product; The flat wire element processed product or the flat wire winding processed product is subjected to insulation treatment to obtain a required flat wire element or the flat wire winding.