Low-voltage asynchronous motor with aluminum flat wire stator slot insulation structure

Abstract

The application relates to the technical field of energy-saving motors, in particular to a low-voltage asynchronous motor with an aluminum flat wire stator slot opening insulation structure, which comprises a stator core, a front end cover, a rear end cover, a rotor assembly, a stator slot, insulation paper and a stator winding, and further comprises an enlarged slot opening, a winding self-adaptive compression assembly, a positioning assembly, a heat-conducting support framework and a heat dissipation assembly; the enlarged slot opening is symmetrically arranged on the left and right sides of the slot opening of the stator slot; through the cooperative mode of the enlarged slot opening, the winding self-adaptive compression assembly, the positioning assembly, the heat-conducting support framework and the heat dissipation assembly, the problems that the aluminum flat wire is heat-softened due to the slot opening heat convergence effect, lacks rigid constraint and is easy to be deformed in the radial direction and the insulation structure is damaged under the working condition of high speed, low voltage and large current of the existing aluminum flat wire low-voltage asynchronous motor are solved; the effects of self-adaptive compression deformation prevention, slot opening heat conduction and heat dissipation strengthening and stator winding end vibration suppression are achieved.

Description

Technical Field

[0001] This invention relates to the field of energy-saving electric motor technology, specifically to a low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure. Background Technology

[0002] With the development of new energy electric vehicle technology, higher requirements have been placed on the power density, cost control, and assembly efficiency of energy-saving electric motors. Traditional new energy electric vehicle drive motors mostly use copper windings and all-aluminum shell heat dissipation structures, resulting in higher costs and heavier overall weight for asynchronous motors. In addition, the round copper wire windings in the stator core of traditional asynchronous motors have a low fill factor and generate significant heat. Balancing motor efficiency improvement and heat dissipation optimization under low-voltage 60-96VDC systems is quite difficult. Existing technology installs aluminum flat wire windings in the stator slots of the stator assembly. These aluminum flat wires use square cross-section conductors and are shaped by a forming machine to be manually embedded into the stator slots in a hairpin shape to form distributed windings. The rated operating voltage range of this motor is 60-96VDC, which is suitable for the low-voltage drive platform of new energy vehicles. It also eliminates the traditional external heat dissipation aluminum shell structure and uses the outer circular surface of the stator core as the heat dissipation surface, which simplifies the number of parts and reduces the weight of the motor.

[0003] However, when dealing with current high-speed and low-voltage high-current operating conditions of electric motors (such as high-speed cruising or rapid acceleration of new energy electric vehicles), a large thermal gradient and "heat convergence effect" will be formed at the interface of the stator slot. When the matching shell-less design means that the ends of the suspended aluminum flat wire can only rely on air convection for heat dissipation, the aluminum flat wire will inevitably frequently experience thermal softening and deformation due to extreme high temperature. Moreover, because the traditional aluminum flat wire winding structure does not have a structure that automatically identifies the stress concentration at the slot and enhances the rigidity constraint, the aluminum flat wire will frequently squeeze and impact each other radially at the slot and push out radial bulges. This is especially true when the high-frequency switch of the high-speed inverter generates transient overvoltage, which directly affects the insulation and service safety of the entire low-voltage high-current drive motor system.

[0004] To address this, a low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure. By coordinating the enlarged slot, the winding adaptive clamping component, the positioning component, the thermally conductive support frame, and the heat dissipation component, this invention solves the problems of thermal softening of aluminum flat wire due to slot heat accumulation under high-speed, low-voltage, and high-current conditions in existing aluminum flat wire low-voltage asynchronous motors. These problems include the lack of rigid constraints, easy radial bulging deformation, and damage to the insulation structure. The invention has the effects of adaptive clamping to prevent deformation, enhanced slot heat conduction and heat dissipation, and suppression of stator winding end vibration.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure, belonging to the field of energy-saving motor technology, includes a stator core, a front end cover, a rear end cover, a rotor assembly, stator slots, insulating paper, and stator windings. It also includes enlarged slots, a winding self-adaptive clamping assembly, a positioning assembly, a thermally conductive support frame, and a heat dissipation assembly. The enlarged slots are symmetrically opened on the left and right sides of the stator slot openings. The winding self-adaptive clamping assembly is disposed within the enlarged slot and is attached to the insulating paper. The positioning assembly is disposed at the end of the winding self-adaptive clamping assembly and is connected to the enlarged slot. The thermally conductive support frame is sleeved on the ends of the stator windings and is located at the front and rear ends of the stator core. The heat dissipation assembly is installed on the outer periphery of the stator core. It is connected to the thermally conductive support frame. When the stator winding in the asynchronous motor undergoes thermal softening, the adaptive clamping component applies adaptive elastic pressure within the enlarged slot to constrain the radial deformation of its end. It also acts as a solid thermal bridge to conduct the accumulated heat at the junction of the stator winding slots to the outside. The suspended end of the stator winding extending out of the enlarged slot is three-dimensionally rigidly limited by the thermally conductive support frame. At the same time, through physical contact with the front and rear ends of the stator core, the heat at the end of the stator winding is sent to the stator core and the heat dissipation component. The heat dissipation component is used to tightly lock the thermally conductive support frame to the end of the stator core and conduct the heat absorbed by the thermally conductive support frame from the end of the stator winding to the outer peripheral surface of the stator core for convection heat dissipation.

[0007] Preferably, the winding adaptive clamping assembly includes a connecting plate, a wave-shaped elastic pressure plate, and a heat-conducting block. The connecting plate is disposed inside the enlarged slot, the wave-shaped elastic pressure plate is fixed to the end of the connecting plate, and the heat-conducting block is fixed to the end of the wave-shaped elastic pressure plate and is bonded to the insulating paper.

[0008] Preferably, the positioning component includes a dovetail groove and a dovetail slider. The dovetail groove is formed inside the enlarged slot, and the dovetail slider is slidably connected inside the dovetail groove and is fixedly connected to the connecting plate.

[0009] Preferably, the inner wall bend of the dovetail groove has a rounded corner structure, and the bend of the dovetail slider has a planar structure.

[0010] Preferably, the connection between the stator slot and the enlarged slot is a rounded corner structure, and the outer edge of the insulating paper is a rounded corner structure.

[0011] Preferably, the heat dissipation assembly includes a connecting groove, a connecting block, a mounting groove, and a heat dissipation strip. The connecting groove is symmetrically opened at both ends of the outer periphery of the stator core and is distributed in a circular array along the outer periphery of the stator core. The connecting block is fixed to one end of the thermally conductive support frame near the stator core and is distributed in a circular array along the outer periphery of the thermally conductive support frame. The connecting block is engaged with the connecting groove. The mounting groove is opened on the outer peripheral surface of the stator core and is connected to the connecting groove. The heat dissipation strip is engaged inside the mounting groove and is connected to the connecting block.

[0012] Preferably, the connecting groove has a screw hole inside, the top of the connecting block has an outward protrusion hole, the bottom of the heat sink has symmetrically opened inner expansion holes, the top of the outward protrusion hole is engaged with the bottom of the inner expansion hole, and the top of the heat sink is provided with a fastening bolt that passes through the inner expansion hole and the outward protrusion hole in sequence and is screwed into the screw hole.

[0013] Preferably, the end of the heat dissipation strip is fixedly connected with multiple heat dissipation fins. The multiple heat dissipation fins are arranged in a linear and equally spaced array along the axial direction of the stator core, and the extension direction of each heat dissipation fin is perpendicular to the axis of the stator core. This is to form a multi-channel axial heat dissipation airflow around the stator core, so as to quickly dissipate the heat conducted by the heat dissipation strip to the outside through convection heat transfer.

[0014] Preferably, the thermally conductive support frame has a contoured covering groove on the side surface near the stator winding. The inner wall contour of the contoured covering groove is designed to fit the shape of the suspended end of the stator winding extending out of the groove, so that the suspended end of the stator winding is at least partially embedded in the contoured covering groove. A potting gap is reserved between the inner wall of the contoured covering groove and the outer surface of the stator winding end. The potting gap is filled with a high thermal conductivity insulating potting adhesive layer to form a thermally conductive insulating connection layer between the winding end and the thermally conductive support frame. The bottom of the contoured covering groove is provided with multiple axially penetrating venting and overflow holes to expel internal air and release excess adhesive during the potting process.

[0015] Preferably, the thermally conductive support frame is axially locked to the front and rear ends of the stator core by the heat dissipation assembly, and the end of the thermally conductive support frame extends toward the enlarged slot to form an axial limiting barrier wall, which supports and conducts heat to the suspended end of the stator winding, while sealing the winding adaptive clamping assembly set inside the enlarged slot axially to prevent the winding adaptive clamping assembly from sliding out of the enlarged slot axially.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention, by opening enlarged slots on both sides of the stator slots and incorporating a winding adaptive clamping assembly consisting of a waveform elastic pressure plate and a heat-conducting block, addresses the issue of aluminum flat wire windings softening under extreme high current and attempting to become unstable by radially bulging under electromagnetic force. The waveform elastic pressure plate deforms under pressure and applies an adaptive elastic constraint force in the opposite direction, effectively locking the microscopic displacement trend of the aluminum flat wire. This completely avoids the risk of tearing the insulation paper and varnish layer due to compression. Simultaneously, the heat-conducting block acts as a solid thermal bridge, rapidly drawing and conducting the extreme high heat accumulated at the slot junction outwards, eliminating the "heat accumulation effect" at the slot. This invention addresses the catastrophic accident of transient breakdown and burnout of the slot insulation from both mechanical constraint and active heat dissipation perspectives. It also effectively reduces the operating temperature rise of the stator windings, decreases winding resistance loss, and improves the motor's operating efficiency, demonstrating the technical effect of an energy-saving motor.

[0017] 2. By using the contoured encapsulation groove and high thermal conductivity insulating potting compound layer within the thermally conductive support frame, the ends of the aluminum flat wire, which were originally suspended at both ends, are completely embedded and wrapped within the rigid thermally conductive support frame. Solid thermal conductivity replaces air thermal resistance, and the axially penetrating vent overflow hole design ensures that internal air is completely expelled during potting, eliminating the generation of pores and micro-gaps, and greatly improving dielectric strength. After potting, the loose end windings are integrated with the thermally conductive support frame, reducing mechanical vibration response and further enhancing the heat dissipation capacity of the winding ends, reducing heat loss during operation, which is conducive to the long-term high-efficiency operation of the motor and achieving energy-saving effects.

[0018] 3. Through the fastening bolts of the heat dissipation components, the inner enlarged holes of the heat dissipation strips and the outer protruding holes of the thermal support frame connecting blocks are passed through one point from top to bottom, and finally locked with the screw holes of the stator core. This achieves the interlocking and bolt fastening of three layers of heterogeneous components. The huge axial locking force not only keeps the contact surfaces of heterogeneous metals in a high-pressure bonding state, greatly reducing the interface contact thermal resistance, but also the end extension of the thermal support frame forms an "axial limiting barrier wall". The enlarged slot is blocked by geometric mechanical interference, preventing the clamping components from escaping and sliding out axially under cold and hot cycle creep and severe vibration. Combined with the multi-channel axial heat dissipation airflow formed by the heat dissipation fins on the outer periphery of the stator, forced convection heat transfer is implemented by shearing air, breaking the bottleneck of isolated heat dissipation of each component. While greatly reducing the number of fasteners and simplifying the assembly process of the automated production line, it ensures the safe and stable operation of the low-voltage system under extreme conditions. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a cross-sectional view of the overall structure of the present invention; Figure 3 This is a schematic diagram of the stator core structure of the present invention; Figure 4 This is a cross-sectional view of the stator core structure of the present invention; Figure 5 This is a cross-sectional view of the stator slot structure of the present invention; Figure 6 This is a schematic diagram of the winding adaptive clamping assembly structure of the present invention; Figure 7 This is a schematic diagram of the heat dissipation component structure of the present invention; Figure 8 This is an exploded view of the stator core structure of the present invention.

[0020] In the diagram: 1. Stator core; 2. Front end cover; 3. Rear end cover; 4. Rotor assembly; 5. Stator slot; 51. Insulating paper; 52. Stator winding; 6. Enlarged slot opening; 7. Winding self-adaptive clamping assembly; 71. Connecting plate; 72. Waveform elastic pressure plate; 73. Heat-conducting block; 8. Positioning assembly; 81. Dovetail slot; 82. Dovetail slider; 9. Heat-conducting support frame; 10. Heat dissipation assembly; 101. Connecting slot; 1011. Screw hole; 102. Connecting block; 1021. Outer protrusion hole; 103. Mounting slot; 104. Heat dissipation strip; 1041. Inner enlargement hole; 105. Fastening bolt. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see Figures 1 to 8 This invention provides a low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure, the technical solution of which is as follows: Reference Figure 1 , Figure 2 , Figure 3 , Figure 5 and Figure 6A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure, belonging to the field of energy-saving motor technology, includes a stator core 1, a front cover 2, a rear cover 3, a rotor assembly 4, stator slots 5, insulating paper 51, and stator windings 52. It utilizes the outer circumference of the stator core 1 for direct heat dissipation, eliminating the need for a heat dissipation aluminum shell, reducing the number of parts, and significantly lowering the motor weight. The front cover 2 and rear cover 3 are respectively fixed to the front and rear ends of the stator core 1 to protect the internal structure of the stator core 1. The rotor assembly 4 is located inside the stator core 1 and is connected to the front cover 2 and rear cover 3 respectively. The stator slots 5 are formed through the ends of the stator core 1 and are arranged in a circular array along the outer circumference of the stator core 1. The insulating paper 51 penetrates the interior of the stator slots 5 and is sleeved within them. Located on the surface of the stator winding 52, it is used to significantly reduce contact thermal resistance and improve the continuous output power density of the motor. The stator winding 52 uses square cross-section wire. The aluminum flat wire is formed into a hairpin shape by a forming machine and then manually embedded into the stator slot 5 to form the stator winding 52. By using aluminum flat wire instead of traditional copper round wire, the raw material cost is significantly reduced. At the same time, the aluminum flat wire winding improves the slot fill factor, thereby improving the motor efficiency and power density. It also includes an enlarged slot opening 6, a winding self-adaptive clamping component 7, a positioning component 8, a thermally conductive support frame 9, and a heat dissipation component 10. The enlarged slot opening 6 is symmetrically opened on the left and right sides of the slot opening of the stator slot 5, forming a local enlarged receiving cavity at both ends. It adopts a refined design of "expanding left and right (circumferential) and stabilizing up and down (radial)" to avoid magnetic saturation and iron loss. The heat generated frees up mechanical installation space for the winding adaptive clamping assembly 7. The winding adaptive clamping assembly 7 is located within the enlarged slot 6 and is attached to the insulating paper 51. The entire winding adaptive clamping assembly 7 is positioned inside the enlarged slot 6 and attached to the insulating paper, providing real-time dynamic clamping force to the heat-softened aluminum flat wire of the stator winding 52. When the aluminum flat wire stator winding 52 enters a "heat-softened" state under extreme high current and attempts to become radially bulging and unstable under electromagnetic force, the winding adaptive clamping assembly 7 deforms under pressure and applies an adaptive constraint force in the opposite direction, effectively locking the micro-displacement trend of the aluminum flat wire stator winding 52. This prevents the aluminum flat wire stator winding 52 from deforming, squeezing, and tearing the insulating paper 51 and varnish film. Simultaneously, through the winding adaptive clamping assembly... The heat-conducting block 73 of component 7 rapidly draws the high heat gathered in the enlarged slot 6 outward, eliminating the "heat gathering effect" at the slot. The positioning component 8 is located at the end of the winding adaptive clamping component 7 and is connected to the enlarged slot 6. The positioning component 8 rigidly fixes the winding adaptive clamping component 7 to the inner wall of the enlarged slot 6, providing an assembly channel for the winding adaptive clamping component 7 to slide in easily axially, facilitating assembly. The heat-conducting support frame 9 is sleeved on the end of the stator winding 52 and is located at the front and rear ends of the stator core 1. The heat-conducting support frame 9 is sleeved on the suspended braided sections of the stator winding 52 extending from both ends of the core and is physically and mechanically locked to the front and rear ends of the stator core 1, fixing the originally freely suspended aluminum flat wire stator winding 52 sections into a highly rigid whole.The high-frequency mechanical vibration of the entire machine is dispersed and reduced in space. The thermally conductive support frame 9 can be made of aluminum alloy, thermally conductive composite material, or thermally conductive insulating engineering plastic. The heat dissipation component 10 is installed on the outer periphery of the stator core 1 and is connected to the thermally conductive support frame 9. It is densely installed on the outer peripheral surface of the stator core 1 and is rigidly locked with the thermally conductive support frame 9 with high strength, establishing a heat dissipation and structural closed loop from the end to the outer circle of the stator core 1. Since the working temperature of the stator winding 52 is effectively controlled, the resistance increase of the aluminum flat wire winding caused by temperature rise can be reduced, the winding resistance loss can be reduced, and the electromagnetic energy conversion efficiency can be improved, thereby reducing the power consumption during the operation of the motor. The heat extracted from the end of the thermally conductive support frame 9 and the heat extracted from the slot of the winding adaptive clamping component 7 are uniformly subjected to forced convection heat exchange, completely breaking the heat generation bottleneck. This ensures the safe and stable operation of the low-voltage system under extreme conditions. When the stator winding 52 of the asynchronous motor undergoes thermal softening, the adaptive clamping component 7 applies adaptive elastic pressure within the enlarged slot 6 to constrain the radial deformation of its ends. It also acts as a solid thermal bridge, conducting the accumulated heat at the slot junction of the stator winding 52 outwards. The suspended end of the stator winding 52 extending out of the enlarged slot 6 is rigidly limited by the three-dimensional thermally conductive support frame 9. Simultaneously, through physical contact with the front and rear ends of the stator core 1, the heat from the end of the stator winding 52 is transferred to the stator core 1 and the heat dissipation component 10. The heat dissipation component 10 tightly locks the thermally conductive support frame 9 to the end of the stator core 1 and conducts the heat absorbed by the thermally conductive support frame 9 to the outer peripheral surface of the stator core 1 for convection cooling through the heat dissipation component 10.

[0023] Reference Figure 6In one embodiment of the present invention, the winding adaptive clamping assembly 7 specifically includes a connecting plate 71, a wave-shaped elastic pressure plate 72, and a heat-conducting block 73. The connecting plate 71 is disposed inside the enlarged slot 6 and serves as the rigid frame base of the assembly, connected to the positioning assembly 8. The wave-shaped elastic pressure plate 72 is fixed to the end of the connecting plate 71, providing a continuous circumferential inward elastic restoring force to the heat-conducting block 73. The wave-shaped elastic pressure plate 72 has two waves, and five equal two-wave wave-shaped elastic pressure plates 72 are arrayed along the axial direction of the connecting plate 71. It is made of high-temperature resistant metal material. The wave-shaped elastic pressure plate 72 has a pre-compression amount during installation, and the wave elasticity... The pre-compression amount of the pressure plate 72 is preset based on the radial thermal expansion of the stator winding 52 at its highest operating temperature, ensuring that the corrugated elastic pressure plate 72 always operates within its elastic deformation range during the entire thermal expansion compensation process of the stator winding 52. The maximum compression stroke of the corrugated elastic pressure plate 72 is less than the allowable deformation corresponding to its elastic limit, in order to avoid plastic deformation and stress relaxation during long-term thermal cycling, thereby continuously providing a stable radial restoring force to the heat-conducting block 73. The heat-conducting block 73 is fixed to the end of the corrugated elastic pressure plate 72. When the stator winding 52 expands due to heat and generates radial displacement, it first pushes the insulating paper 51 to move in the direction of the heat-conducting block 73. The heat-conducting block 73 undergoes a slight radial displacement along the enlarged slot 6, and drives the corrugated elastic pressure plate 72 to move. The corrugated elastic plate 72 undergoes elastic compression; as the thermal expansion of the stator winding 52 increases, the compression of the corrugated elastic plate 72 increases synchronously, and its restoring elastic force continues to increase. Through the heat-conducting block 73, it remains in constant contact with the surface of the insulating paper 51, continuously applying radial pressure to the stator winding 52. When the stator winding 52 cools and contracts, the corrugated elastic plate 72 uses its own elastic restoring force to push the heat-conducting block 73 back to its original position. The corrugated elastic plate 72 does not bear a constant compressive load for a long period, but rather undergoes periodic micro-elastic compression and recovery with changes in the thermal expansion of the stator winding 52. During the motor cooling process, it can synchronously release elastic strain and return to its initial state, thereby avoiding permanent plastic deformation caused by continuous unidirectional loading. Furthermore, its contact with the insulating paper 51 is continuous. Next, the heat-conducting block 73 is pressed against the surface of the insulating paper 51, acting as a heat conduction bridge between the aluminum flat wire stator winding 52 and the outside. The heat-conducting block 73 is made of a high thermal conductivity insulating material, including aluminum nitride ceramic, boron nitride composite material, or graphite-reinforced insulating material. A thermally conductive insulating interface layer is set between the heat-conducting block 73 and the insulating paper 51. The interface layer can be made of thermally conductive silicone grease, thermally conductive gel, or thermally conductive insulating adhesive to reduce contact thermal resistance. The heat generated by the stator winding 52 is transferred to the heat-conducting block 73 through the insulating paper 51, and then conducted to the thermally conductive support frame 9 through the connecting plate 71, and finally dissipated to the outside through the heat dissipation component 10. The heat generated by the stator winding 52 is transferred to the thermally conductive support frame 9 in sequence through the insulating paper 51, the heat-conducting block 73, and the connecting plate 71.This heat is further transferred to the heat dissipation component 10 to form a continuous solid heat conduction path; the heat-conducting block 73 not only bears the force transmission during elastic compression, but also undertakes the function of rapid heat dissipation from the slot opening.

[0024] Reference Figure 5 and Figure 6 As one embodiment of the present invention, specifically, the positioning component 8 includes a dovetail groove 81 and a dovetail slider 82. The dovetail groove 81 is formed inside the enlarged slot 6, and the dovetail slider 82 is slidably connected inside the dovetail groove 81 and is fixedly connected to the connecting plate 71. The dovetail connection structure can provide stable installation positioning for the winding adaptive clamping component 7, restrict its movement direction in the enlarged slot 6, and ensure that the winding adaptive clamping component 7 always maintains the correct position during operation and accurately applies pressure to the stator winding 52.

[0025] Reference Figure 5 and Figure 6 As one embodiment of the present invention, specifically, the inner wall bend of the dovetail groove 81 is a rounded corner structure, and the bend of the dovetail slider 82 is a planar structure. The rounded corner structure of the inner wall bend of the dovetail groove 81 and the planar structure of the bend of the dovetail slider 82 can reduce sliding friction, making the movement of the winding adaptive clamping assembly 7 smoother when it is inserted into the enlarged slot 6, and improving its adaptive clamping response speed and accuracy.

[0026] Reference Figure 4 and Figure 5 In one embodiment of the present invention, specifically, the connection between the stator slot 5 and the enlarged slot 6 is a rounded corner structure. Traditional stator slot 5 openings are usually right angles or steps with sharp corners. Since the enlarged slot 6 is formed by the local circumferential expansion of laminations, a stepped surface is formed at its interface with the conventional stator slot 5. When the aluminum flat wire stator winding 52 is thermally expanded or generates high-frequency alternating vibration, this interface becomes a "bottleneck" for stress wave transmission. Designing it as a rounded corner structure can smoothly transition the discontinuous geometric cross-section. This allows for axial insertion of the winding adaptive clamping assembly 7 (especially the dovetail slider 82 and connecting plate 71) and axial... During insertion, the rounded corner provides a microscopic introduction slope to prevent microscopic tearing or delamination of the silicon steel sheets at the edge of the stator core 1. The outer edge of the insulating paper 51 has a rounded corner structure. When the stator winding 52 softens due to heat and attempts to generate radial expansion (bulge), the stator winding 52 will exert pressure on the heat-conducting blocks 73 on both sides. The insulating paper 51 sandwiched in the middle will be subjected to severe circumferential compression and local shear force. If the outer edge of the insulating paper 51 is a sharp right angle, under reciprocating compression and high-frequency alternating vibration, the right angle edge is very likely to become the source of crack initiation. The rounded corner structure can evenly distribute and dissipate the concentrated shear stress along the tangent direction of the rounded corner.

[0027] Reference Figure 3 and Figure 8 In one embodiment of the present invention, the heat dissipation assembly 10 specifically includes a connecting groove 101, a connecting block 102, a mounting groove 103, and heat dissipation strips 104. The connecting groove 101 is symmetrically opened at both ends of the outer periphery of the stator core 1, and is distributed in a circular array along the outer periphery of the stator core 1. The connecting block 102 is fixed to one end of the heat-conducting support frame 9 near the stator core 1, and is distributed in a circular array along the outer periphery of the heat-conducting support frame 9. The connecting block 102 is engaged with the connecting groove 101, and the connecting block 102 is engaged with the circumferential center array of the connecting groove 101, providing high-precision circumferential and radial primary positioning for the entire machine. To ensure that the heat-conducting support frame 9 does not deflect at an angle during assembly, the mounting groove 103 is opened on the outer peripheral surface of the stator core 1 and is connected to the connecting groove 101. The heat dissipation strip 104 is engaged inside the mounting groove 103 and is connected to the connecting block 102. The heat dissipation strip 104 is directly engaged in the mounting groove 103 on the outer periphery of the stator core 1 and is in direct physical contact with the connecting block 102 at the end. This allows the heat conducted from the stator groove 5 to the surface of the stator core 1, as well as the heat from the end winding absorbed by the heat-conducting support frame 9, to be seamlessly gathered on the heat dissipation strip 104, breaking the bottleneck of isolated heat dissipation of each component in the traditional structure.

[0028] Reference Figure 7 and Figure 8As one embodiment of the present invention, specifically, a screw hole 1011 is provided inside the connecting groove 101, an outward protruding hole 1021 is provided at the top of the connecting block 102, and an inwardly enlarged hole 1041 is symmetrically provided at the bottom of the heat dissipation strip 104. The top of the outwardly protruding hole 1021 is engaged with the bottom of the inwardly enlarged hole 1041. A fastening bolt 105 is provided at the top of the heat dissipation strip 104, which passes through the inwardly enlarged hole 1041 and the outwardly protruding hole 1021 and is screwed into the screw hole 1011. By utilizing the stepped geometric interference of "outwardly protruding hole 1021 entering inwardly enlarged hole 1041", a single-point through-type fastening of the three heterogeneous components (stator core 1, thermally conductive support frame 9, and heat dissipation strip 104) is achieved with a single fastening bolt 105. When the motor is running (especially with high current and rapid acceleration), it will generate High-frequency mechanical vibration makes the suspended heat-conducting support frame 9 prone to microscopic cantilever beam vibration. The fastening bolts 105 firmly press and fasten the heat sink 104 and connecting block 102 into the screw holes 1011 of the stator core 1 from top to bottom, fixing the three originally independent components into a highly rigid mechanical whole. The vibration resistance and torsional resistance have undergone a qualitative leap. The huge axial locking force provided by the fastening bolts 105 forcibly squeezes the microscopic gaps between the connecting block 102 and the connecting groove 101, and between the heat sink 104 and the mounting groove 103, so that the metal contact surface is in a high-pressure bonding state, which greatly reduces the interface contact thermal resistance and ensures unobstructed heat conduction. The staggered interlocking design of "one bolt through three parts" greatly reduces the number of fasteners and simplifies the bolt tightening process of automated production line assembly.

[0029] Reference Figure 1 , Figure 3 and Figure 8 In one embodiment of the present invention, specifically, multiple heat dissipation fins are fixedly connected to the end of the heat dissipation strip 104. The multiple heat dissipation fins are arranged in a linear, equally spaced array along the axial direction of the stator core 1, and the extension direction of each heat dissipation fin is perpendicular to the axis of the stator core 1, so as to form a multi-channel axial heat dissipation airflow around the stator core 1. The heat conducted by the heat dissipation strip 104 is quickly dissipated to the outside through convection heat transfer. Since the traditional heavy aluminum shell is eliminated, the stator core 1 is directly exposed. When the car is moving (or when the rotor assembly 4 rotates and drives the surrounding air), the oncoming airflow or shear force is generated. The airflow will pass through these axial heat dissipation airways from front to back or from back to front along a direction perpendicular to the fins. The heat dissipation fins greatly expand the effective convective heat transfer area. The heat gathered by the heat dissipation bars 104 is quickly "washed away" and carried away by the forced convective airflow in the dense air channels, eliminating local heat accumulation points at the stator slot 5 opening and stator core 1. This ensures that the low-voltage high-current motor does not overheat, demagnetize, or experience insulation thermal aging under extreme continuous loads. At the same time, it reduces the overall temperature rise of the stator winding 52, enabling the motor to maintain high operating efficiency for a long time, reducing additional energy losses caused by temperature rise, and improving energy utilization.

[0030] Reference Figure 3 and Figure 8 In one embodiment of the present invention, specifically, a contoured covering groove is formed on the surface of the thermally conductive support frame 9 near the stator winding 52. The inner wall contour of the contoured covering groove is adapted to the shape of the suspended end of the stator winding 52 extending out of the groove, so that the suspended end of the stator winding 52 is at least partially embedded in the contoured covering groove. Through the contoured covering groove and the high thermal conductivity insulating potting compound, the end of the aluminum flat wire stator winding 52 is completely wrapped, and the thermal resistance of air is completely replaced by solid thermal conductivity and adhesive thermal conductivity, which is equivalent to installing a heat-conducting layer at the end of the stator winding 52. A highly efficient "heat suction pump" instantly draws heat from the flat wire end, which generates a large amount of heat, and transfers it to the thermally conductive support frame 9. The thermally conductive support frame 9, as the main load-bearing component at the winding end, only fills the gap between the winding end and the contoured coating groove after the high thermal conductivity insulating potting compound has cured, to establish a continuous thermal interface and absorb local micro-vibrations. It does not bear the main support load of the stator winding 52. Most of the electromagnetic load on the stator winding 52 is transferred to the stator core 1 through the thermally conductive support frame 9. The inner wall of the contoured coating groove and the stator winding 52... A potting gap is reserved between the outer surfaces of the ends. This gap is filled with a high thermal conductivity insulating potting compound to form a thermally conductive insulating connection layer between the winding ends and the thermally conductive support frame 9. The bottom of the contoured encapsulation groove has multiple axially penetrating venting and overflow holes to expel internal air and release excess adhesive during the potting process. Residual air during potting can easily lead to partial discharge or breakdown. The axially penetrating venting and overflow holes ensure that air is completely expelled as the adhesive progresses from the inside out. Excess adhesive overflow serves as a full mark, eliminating internal pores and ensuring... With extremely high dielectric strength and thermal uniformity, after potting, the thermally conductive support frame 9 covers the suspended end of the stator winding 52, which significantly shortens the original free length of the cantilever and improves the overall bending stiffness of the end. When alternating electromagnetic force is applied to the stator winding 52, the thermally conductive support frame 9 reduces the amplitude of the mechanical vibration response of the winding end by restricting the radial, axial and circumferential free displacement of the winding end. This integrates the originally loose and multi-branched aluminum flat wire stator winding 52 end with the rigid thermally conductive support frame 9, giving the end the ability to resist the vibration of strong electromagnetic reaction force.

[0031] Reference Figure 2 , Figure 3 and Figure 8In one embodiment of the present invention, specifically, the thermally conductive support frame 9 is axially locked to the front and rear ends of the stator core 1 by the heat dissipation assembly 10, and the end of the thermally conductive support frame 9 extends toward the enlarged slot 6 to form an axial limiting barrier. The radial load generated during the operation of the winding adaptive clamping assembly 7 is sequentially transmitted to the inner wall of the enlarged slot 6 through the thermally conductive block 73, the wave elastic pressure plate 72, the connecting plate 71, and the dovetail slider 82 to form a first force path; the alternating electromagnetic load on the winding end is transmitted to the stator core 1 through the thermally conductive support frame 9 to form a second force path. The two force paths together form a stable closed-loop force transmission system, which supports and conducts heat to the suspended end of the stator winding 52, while sealing the axial end face of the winding adaptive clamping assembly 7 located inside the enlarged slot 6 to prevent the winding adaptive clamping assembly 7 from sliding out of the enlarged slot 6 axially. The support frame 9 itself undertakes the task of end support and heat conduction, and its end also takes on the function of "axial limiting wall". There is no need to design, manufacture and assemble special axial retaining rings or snap rings, which reduces the number of parts. The winding adaptive clamping component 7 (which includes wave elastic pressure plate 72, dovetail slider 82, etc.) set inside the enlarged slot 6 has a fatal risk of "slowly moving, sliding out or escaping" along the dovetail slot 81 when facing the cold and hot cycle creep compression and vibration of aluminum flat wire stator winding 52 for a long time. This limiting wall directly and physically "blocks" the exit of the enlarged slot 6 from the end faces at both ends. There is no need to rely on glue or welding to fix the winding adaptive clamping component 7 inside the enlarged slot 6. It relies purely on geometric mechanical interference to lock, avoiding the problem of glue aging and failure under long-term high temperature and high vibration, which greatly improves the operational stability of the motor throughout its entire life cycle.

[0032] Working principle: When the asynchronous motor operates under low voltage, high current, and high speed conditions, when the stator winding 52 softens due to heat and exhibits a radial expansion tendency under mechanical vibration, the stator winding 52 within the enlarged slot 6 will apply pressure to the winding adaptive clamping components 7 on both sides. At this time, the winding adaptive clamping components 7 will adaptively clamp the sides of the stator winding 52 according to the applied pressure, ensuring that the stator winding 52 is always kept in a close and tight state. This adaptively counteracts the radial deformation tendency of the stator winding 52, preventing the stator winding 52 from bulging and damaging the insulation layer at the slot. The adaptive clamping assembly 7 is fixed inside the enlarged slot 6 by the positioning assembly 8 to apply pressure to the stator winding 52. The thermally conductive support frame 9 is fixed to both ends of the stator core 1 by the heat dissipation assembly 10, forming an axial limiting barrier. This axially limits the adaptive clamping assembly 7 inside the enlarged slot 6, preventing it from slipping out. Simultaneously, the thermally conductive support frame 9 provides three-dimensional rigid restraint to the suspended end of the stator winding 52, effectively suppressing high-frequency alternating vibration at the suspended end of the stator winding 52 and allowing the winding inside the stator slot 5 to... Most of the heat generated by the aluminum flat wire stator winding 52 can be conducted through the stator core 1 to the heat dissipation assembly 10 on the outer periphery for dissipation. The heat accumulated at the slot opening of the stator slot 5 and the heat generated at the suspended end of the stator winding 52 will be conducted through the winding self-adaptive clamping assembly 7 and the high thermal conductivity insulating potting compound layer to the thermally conductive support frame 9. The thermally conductive support frame 9 then conducts the heat to the heat dissipation assembly 10, and finally, the heat is dissipated through convection by the heat dissipation assembly 10. This effectively avoids heat accumulation at the slot opening of the stator slot 5, delays insulation aging, and prevents heat accumulation in the stator slot from both heat dissipation and structural constraints. The problem of the slot insulation being broken down and burned ensures the stability and safety of the low-voltage asynchronous motor under the low-cost shell-free design. Throughout the entire hot and cold cycle, the waveform elastic pressure plate 72 is always in an elastic working state. Its elastic restoring force can automatically compensate for the dimensional changes of the stator winding 52 caused by temperature changes, so that the heat-conducting block 73 is continuously attached to the surface of the insulating paper 51. At the same time, the heat-conducting support frame 9 continuously restricts the three-dimensional displacement freedom of the winding end and quickly dissipates the heat at the end, thereby enabling the winding end to maintain a stable support state and good heat dissipation capacity for a long time.

[0033] Specifically, when the stator winding 52 softens due to heat and exhibits a radial expansion tendency, the stator winding 52 within the enlarged slot 6 applies pressure to the heat-conducting blocks 73 on both sides. This causes the wave-shaped elastic pressure plate 72 to elastically deform according to the applied pressure, leading the heat-conducting blocks 73 to adaptively press the sides of the stator winding 52. This ensures that the stator winding 52 remains in a close and tight state, adaptively counteracting the radial deformation tendency of the stator winding 52 and preventing the stator winding 52 from bulging and damaging the insulation layer at the slot. At the same time, the heat-conducting block 73 acts as a solid thermal bridge, conducting the heat accumulated at the junction of the stator winding 52 slots to the outside, effectively alleviating the heat accumulation effect. The winding adaptive clamping assembly 7 is slidably connected to the dovetail slot 81 through the dovetail slider 82, so that the winding adaptive clamping assembly 7 can be fixed inside the enlarged slot 6. When installing the heat-conducting support frame 9, first attach the heat-conducting support frame 9 to the end of the stator core 1 so that the connecting block 102 is inserted into the inside of the connecting slot 101, and then the heat dissipation... The heat sink 104 is installed inside the mounting groove 103 on the outer periphery of the stator core 1, so that the outward protrusion 1021 on the connecting block 102 engages with the inner expansion hole 1041 on the heat sink 104, temporarily limiting the heat sink 104 and the connecting block 102 together. Then, the fastening bolt 105 is used to pass through the inner expansion hole 1041 and the outward protrusion 1021 in sequence, so that it is finally connected to the screw hole 1011. Finally, the fastening bolt 105 is tightened to fix it to the screw hole 1011, thus fixing the heat sink 104 on the outer periphery of the stator core 1, and allowing the thermally conductive support frame 9 to be installed at the end of the stator core 1. During the entire hot and cold cycle, the waveform elastic pressure plate 72 continuously provides stable elastic compensation, and the thermally conductive support frame 9 continuously restricts the vibration of the winding end and quickly dissipates heat, so that the stator winding always maintains a low operating temperature rise, reduces the resistance loss of the aluminum flat wire winding, improves the energy conversion efficiency of the motor, and achieves energy-saving operation while ensuring safe and reliable operation.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure, belonging to the technical field of energy-saving motors, comprising a stator core, a front end cover, a rear end cover, a rotor assembly, stator slots, insulating paper, and stator windings, characterized in that: It also includes an enlarged slot, a winding adaptive clamping assembly, a positioning assembly, a thermally conductive support frame, and a heat dissipation assembly. The enlarged slots are symmetrically opened on the left and right sides of the stator slot opening. The winding adaptive clamping assembly is disposed within the enlarged slot and is attached to the insulating paper. The positioning assembly is disposed at the end of the winding adaptive clamping assembly and is connected to the enlarged slot. The thermally conductive support frame is sleeved on the end of the stator winding and is located at the front and rear ends of the stator core. The heat dissipation assembly is installed on the outer periphery of the stator core and is connected to the thermally conductive support frame. When thermal softening occurs in the stator winding of the asynchronous motor, the adaptive clamping assembly... The component applies adaptive elastic pressure within the enlarged slot to constrain the radial deformation of its ends and acts as a solid thermal bridge to conduct the accumulated heat at the junction of the stator winding slots to the outside. The suspended end of the stator winding extending out of the enlarged slot is three-dimensionally rigidly limited by the thermally conductive support skeleton. At the same time, through physical contact with the front and rear ends of the stator core, the heat at the end of the stator winding is sent to the stator core and the heat dissipation assembly. The heat dissipation assembly is used to tightly lock the thermally conductive support skeleton to the end of the stator core and conduct the heat absorbed by the thermally conductive support skeleton from the end of the stator winding to the outer peripheral surface of the stator core for convection heat dissipation through the heat dissipation assembly.

2. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 1, characterized in that: The winding adaptive clamping assembly includes a connecting plate, a wave-shaped elastic pressure plate, and a heat-conducting block. The connecting plate is disposed inside the enlarged slot, the wave-shaped elastic pressure plate is fixed to the end of the connecting plate, and the heat-conducting block is fixed to the end of the wave-shaped elastic pressure plate and is bonded to the insulating paper.

3. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 2, characterized in that: The positioning component includes a dovetail groove and a dovetail slider. The dovetail groove is formed inside the enlarged slot, and the dovetail slider is slidably connected inside the dovetail groove and is fixedly connected to the connecting plate.

4. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 3, characterized in that: The inner wall of the dovetail groove has a rounded corner structure at the bend, while the bend of the dovetail slider has a planar structure.

5. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 1, characterized in that: The connection between the stator slot and the enlarged slot is a rounded corner structure, and the outer edge of the insulating paper is a rounded corner structure.

6. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 1, characterized in that: The heat dissipation assembly includes a connecting groove, a connecting block, a mounting groove, and a heat dissipation strip. The connecting groove is symmetrically opened at both ends of the outer periphery of the stator core and is distributed in a circular array along the outer periphery of the stator core. The connecting block is fixed to one end of the thermally conductive support frame near the stator core and is distributed in a circular array along the outer periphery of the thermally conductive support frame. The connecting block is engaged with the connecting groove. The mounting groove is opened on the outer peripheral surface of the stator core and is connected to the connecting groove. The heat dissipation strip is engaged inside the mounting groove and is connected to the connecting block.

7. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 6, characterized in that: The connecting groove has a screw hole inside, the top of the connecting block has an outward protrusion hole, the bottom of the heat sink has symmetrically opened inner expansion holes, the top of the outward protrusion hole is engaged with the bottom of the inner expansion hole, and the top of the heat sink is provided with a fastening bolt that passes through the inner expansion hole and the outward protrusion hole in sequence and is screwed into the screw hole.

8. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 6, characterized in that: The end of the heat dissipation bar is fixedly connected with multiple heat dissipation fins. The multiple heat dissipation fins are arranged in a linear and equally spaced array along the axial direction of the stator core, and the extension direction of each heat dissipation fin is perpendicular to the axis of the stator core. This is to form a multi-channel axial heat dissipation air path on the outer periphery of the stator core, so as to quickly dissipate the heat conducted by the heat dissipation bar to the outside through convection heat transfer.

9. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 1, characterized in that: The heat-conducting support frame has a contoured covering groove on the side surface near the stator winding. The inner wall contour of the contoured covering groove is designed to fit the shape of the suspended end of the stator winding extending out of the groove, so that the suspended end of the stator winding is at least partially embedded in the contoured covering groove. A potting gap is reserved between the inner wall of the contoured coating groove and the outer surface of the stator winding end. The potting gap is filled with a high thermal conductivity insulating potting adhesive layer to form a thermally conductive insulating connection layer between the winding end and the thermally conductive support frame. The bottom of the contoured coating groove is provided with multiple axially penetrating venting and overflow holes to expel internal air and release excess adhesive during the potting process.

10. A low-voltage asynchronous motor with an aluminum flat wire stator slot insulation structure according to claim 1, characterized in that: The thermally conductive support frame is axially locked to the front and rear ends of the stator core by the heat dissipation assembly, and the end of the thermally conductive support frame extends toward the enlarged slot to form an axial limiting barrier. This is used to support and conduct heat to the suspended end of the stator winding, while sealing the axial end face of the winding adaptive clamping assembly set inside the enlarged slot to prevent the winding adaptive clamping assembly from sliding out of the enlarged slot axially.

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