A stator busbar structure, a stator assembly and an electric machine

Abstract

The utility model discloses a kind of stator busbar structure, stator assembly and motor, stator busbar structure includes: stator winding, the stator winding has outgoing terminal;Busbar assembly, the busbar assembly has conducting part, the welding point is formed with the welding of the conducting part and the outgoing terminal;Positioning member, the outgoing terminal and the conducting part are fixed to the positioning member, to enhance the strength of the welding point.The utility model utilizes positioning member before the welding of the conducting part and the outgoing terminal of busbar assembly's conducting part and stator winding, fixes conducting part and outgoing terminal, and then can continuously exert pressing force to conducting part and outgoing terminal, can reduce the stress received by welding point after welding, improve the strength of welding point, so that welding point can withstand vibration of different frequency, to protect welding point.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, and in particular to a stator busbar structure, a stator assembly, and a motor. Background Technology

[0002] In existing automotive generators, the stator three-phase windings are typically connected in a star or delta configuration using copper busbars, which serve as current paths to lead the winding outputs to the controller. To balance space constraints and low impedance, one end of the busbar is directly soldered to the stator coil output terminal, while the other end is rigidly fixed to the controller terminal with bolts.

[0003] However, with the increasing integration of generator-transmission systems in hybrid and range-extended electric vehicles, the stator assembly is directly fixed to the transmission housing, belonging to a different bracket than the controller. In transmission vibration tests, the two exhibit significantly different modal characteristics due to differences in mass and stiffness: when the excitation frequency approaches the system's coupled modes, the stator and controller experience opposite relative displacements, causing the Busbar weld area to withstand alternating bending and shear loads. Because the weld itself has high hardness and low toughness, it is highly susceptible to microcracks under long-term fatigue impact, eventually expanding into through-cracks, leading to increased contact resistance or even open circuits, affecting the overall vehicle reliability.

[0004] Existing technologies mainly alleviate stress by increasing the cross-sectional area of ​​the copper busbar or by using multi-point bolt connections. However, the former sacrifices axial space, and the latter still cannot eliminate fatigue damage caused by high-frequency micro-amplitude vibration. Therefore, there is an urgent need for a stator busbar structure that can maintain electrical continuity and resist fatigue under vibration. In addition, no positioning components are set to constrain the relative position and vibration deformation between the busbar and the stator winding, making it difficult to suppress the initiation and propagation of fatigue cracks in the welded area. Utility Model Content

[0005] The purpose of this invention is to provide a stator busbar structure, a stator assembly, and a motor to enhance the strength of the welded joints and solve the problem of busbar breakage during vibration.

[0006] In a first aspect, this utility model provides a stator busbar structure, comprising: Stator winding, the stator winding having lead-out terminals; A busbar assembly having a conductive part, the conductive part being welded to the output terminal, and a welding point being formed at the welding point between the conductive part and the output terminal; A positioning element, which is used to fix the outlet end and the conductive part.

[0007] In the stator bus structure described above, preferably, the positioning member has a positioning space, and both the conductive part and the output terminal extend through the positioning space.

[0008] In the stator busbar structure described above, preferably, the positioning element includes a positioning block, the positioning block has a positioning hole, the positioning hole is disposed through the positioning block, and the space inside the positioning hole forms the positioning space.

[0009] In the stator bus structure described above, preferably, the positioning member further includes a positioning seat, and the positioning blocks include a plurality of blocks spaced apart from each other on the positioning seat. In the stator bus structure described above, preferably, the bus assembly includes a hard copper busbar, the hard copper busbar including the conductive portion and a lead-out end, the hard copper busbar extending along a conductive path from the conductive portion to the lead-out end.

[0010] In the stator bus structure described above, preferably, the lead-out end is provided with a connection terminal, and the connection terminal is provided with a bolt hole for conductive connection with the controller, so as to transmit the current of the hard copper bus to the controller.

[0011] In the stator bus structure described above, preferably, the stator bus structure further includes a mounting base, on which the bus assembly is mounted.

[0012] In the stator bus structure described above, preferably, the positioning member is detachably connected to the fixing base.

[0013] Secondly, this utility model provides a stator assembly, including a stator body, and the stator assembly further includes the aforementioned stator busbar structure; The stator windings are wound around the stator body.

[0014] Thirdly, this utility model provides an electric motor, including the aforementioned stator assembly.

[0015] Compared with the prior art, this utility model uses a positioning component to fix the conductive part and the output end of the stator winding before welding. This allows for continuous pressure to be applied to the conductive part and the output end, reducing the stress on the weld point after welding, increasing the strength of the weld point, and enabling the weld point to withstand vibrations of different frequencies, thus protecting the weld point. Attached Figure Description Figure 1 This is a perspective view of the stator busbar structure provided in an embodiment of this utility model.

[0016] Figure 2This is a perspective view of the bus assembly provided in an embodiment of the present invention.

[0017] Figure 3 This is a perspective view of the positioning component provided in an embodiment of this utility model.

[0018] Explanation of reference numerals in the attached figures: 10-Bus assembly, 11-Conductive part, 12-Lead-out terminal, 13-Fixing base, 14-Bus body; 20 - Welding point; 30-Positioning component, 31-Positioning space, 32-Positioning block, 33-Positioning hole, 34-Positioning seat; 40 - Connecting terminal, 41 - Bolt hole. Detailed Implementation

[0019] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] Firstly, referring to Figure 1 As shown, this utility model provides a stator busbar structure, including a stator winding (not shown), a busbar assembly 10, and a positioning member 30, wherein: The stator winding has a lead-out end, which is formed by the extension of the last turn of the positioning winding and can be electrically connected to the bus assembly 10 to transmit current.

[0021] Reference Figure 2 As shown, the bus assembly 10 has a conductive part 11, which is an extension of the bus body 14. The conductive part 11 overlaps with the output end of the stator winding, specifically, it can be a surface-to-surface overlap or a line-to-surface overlap. After the overlap surface is welded, a welding point 20 is formed at the welding point between the conductive part 11 and the output end (the location of the welding point 20 is marked in the figure). The welding point 20 can be fixed and supported by the conductive part 11 and the output end at the same time, which can significantly reduce the vibration bending moment on the welding point 20, thereby enhancing the strength of the welding point 20.

[0022] The positioning member 30 is used to fix the lead-out end and the conductive part 11 to enhance the strength of the welding point 20. The positioning member 30 fixes the position of the lead-out end and the conductive part 11 at the same time, and its rigid wall surface can form a lateral limit, thereby diverting the mechanical load that was originally borne only by the weld to the body of the positioning member 30.

[0023] Before welding, the positioning element 30 can continuously provide clamping force to the overlapping surface of the lead-out end and the conductive part 11. After welding, the clamping force still exists, so that the welding point 20 is always in a constrained state. The welding point 20 changes from the original suspended state to a fixed state. When vibration occurs, the positioning element 30 deforms first and absorbs the shear displacement component, so that the welding point 20 only bears the attenuated residual stress. The residual stress level is lower than the fatigue limit of the weld, which greatly reduces the probability of cracks in the welding point 20, thereby improving the strength of the welding point 20.

[0024] In the embodiments provided in this application, reference is made to Figure 3 As shown, the positioning component 30 has a positioning space 31. The conductive part 11 and the lead end both extend through the positioning space 31. After extending through the positioning space 31, they are welded to form a weld point 20. The contour of the positioning space 31 matches the outer contour of the lead end and the conductive part 11, so that the positioning space 31 provides geometric boundaries and a place to accommodate the lead end and the conductive part 11. During assembly, the lead end and the conductive part 11 are directly placed into the positioning space 31. The wall surface of the positioning space 31 can achieve lateral centering and axial limiting to fix the position of the lead end, the conductive part 11 and the weld point 20, thereby eliminating the swinging degree of freedom of the suspended weld point 20, so that the welding area is always in a controlled geometric position before and after welding.

[0025] After welding, the weld and heat-affected zone are located entirely or partially within the positioning space 31, transforming the welding point 20 from a free cantilever into a fixed support node with its perimeter covered. When external vibration causes relative displacement between the stator and controller, the sidewall of the positioning space 31 first deforms to absorb shear and bending displacement components. The welding point 20, being contained, moves synchronously with the positioning component 30, significantly reducing the dynamic stress borne by the welding point 20 and blocking the path to crack formation. Thus, it can remain stable under long-term vibration conditions without the need to increase the cross-section of the copper busbar or add redundant fasteners.

[0026] In one feasible implementation, continue to refer to Figure 3 As shown, the positioning component 30 includes a positioning block 32, on which a positioning hole 33 is provided. The positioning hole 33 penetrates the positioning block 32, and the space within the positioning hole 33 forms a positioning space 31. The positioning block 32 serves as the direct carrier of the positioning space 31 and also undertakes the functions of clamping, limiting, and diverting. The positioning hole 33 provides an insertion channel for the lead-out end and the conductive part 11, and generates lateral constraint force around the entire circumference of the hole wall. This reduces the need for additional clamps or other components to hold the lead-out end and the conductive part 11. During the welding process, the overlapping surfaces of the lead-out end and the conductive part 11 always remain tightly fitted without gaps.

[0027] The positioning hole 33 of this application is completely through the thickness direction of the positioning block 32, forming a channel with open ends, allowing the lead-out end and the conductive part 11 to be inserted from one side and extended from the other side, which facilitates the approach of the laser or resistance welding gun to the welding area. Under vibration load, the hole wall of the positioning hole 33 deforms and absorbs the shear displacement component first. The welding point 20 moves synchronously with the hole wall and no longer bears high stress independently. As a result, the dynamic stress level of the welding point 20 is significantly attenuated, the path of crack generation is blocked, and the strength of the welding point 20 is correspondingly enhanced.

[0028] In this embodiment, the positioning element 30 is an injection-molded block. In other embodiments, the positioning element 30 may also be a metal insert or a composite molded part, as long as it has sufficient rigidity to transmit the clamping force. This is not limited here.

[0029] Furthermore, the positioning component 30 also includes a positioning seat 34, and multiple positioning blocks 32 are spaced apart on the positioning seat 34. The multiple positioning blocks 32 spaced apart on the positioning seat 34 form a split positioning array, allowing multiple positioning holes 33 to simultaneously position multiple welding points 20. If one positioning hole 33 fails due to wear or overheating, the remaining positioning blocks 32 can still continue to operate without stopping the machine to remove wires, effectively reducing maintenance costs and ensuring the reliability of the stator busbar structure.

[0030] In order to improve the mode of the bus assembly 10, in the embodiments provided in this application, the bus assembly 10 includes a hard copper bus, which includes a conductive part 11 and a lead-out end 12. The hard copper bus extends from the conductive part 11 to the lead-out end 12 along the conductive path.

[0031] Hard copper busbars are rigid copper busbars made of a single piece, without any layers, and are integrally formed. Hard copper busbars provide a conductive backbone with low impedance and high current carrying capacity, and can also serve as mechanical load-bearing components. Compared with the multi-layer soft copper busbars used in the prior art, the use of hard copper busbars can reduce the welding process and the number of required parts, which helps to reduce costs.

[0032] The conductive part 11 of the hard copper busbar is used to collect the current of the stator winding, and the lead-out end 12 is used to output the current to the outside. The current flows in from the conductive part 11 and is transmitted to the lead-out end 12 through the continuous hard copper busbar. The transmission path has no cross-sectional change, which can eliminate intermediate transition resistance and reduce heat generation.

[0033] Furthermore, referring to Figure 2As shown, the lead-out end 12 is provided with a connection terminal 40, and the connection terminal 40 is provided with a bolt hole 41. The bolt hole 41 is used for conductive connection with the controller to transfer the current of the hard copper busbar to the controller. The connection terminal 40 is the connection port between the busbar assembly 10 and the controller, and it needs to have the dual functions of conductivity and mechanical fastening. The bolt hole 41 penetrates through the thickness direction of the connection terminal 40 to form a detachable rigid conductive node, while being able to withstand the compressive stress brought by the locking torque.

[0034] The connection terminal 40 is provided with bolt holes 41, which can guide the three-phase current collected by the hard copper busbar into the controller power board or busbar at one time, completing the transfer of electrical energy from the stator side to the control side.

[0035] Under vibration conditions, bolt hole 41 is located at the end of the hard copper busbar furthest from positioning element 30. The deformation of the hard copper busbar absorbs relative displacement, and the area of ​​bolt hole 41 only bears the attenuated residual fretting. Welding point 20 is in a low deformation zone due to its proximity to positioning element 30. Bolt hole 41 and welding point 20 form a gradient stress distribution at both ends of the hard copper busbar, with one end being detachable and the other end being fixed support. This ensures maintainability and prevents weld failure due to vibration fatigue.

[0036] To further reduce the bending moment at weld point 20, in the embodiments provided in this application, reference is made to... Figure 2 As shown, the stator bus structure also includes a mounting base 13, on which the bus assembly 10 is mounted. The mounting base 13 is a rigid or elastic support independent of the positioning member 30, and can be integrally formed from insulating material, used to support and lock the bus assembly 10. The mounting base 13 can be set in the middle section of the bus assembly 10 or near the welding point 20 to form a second support point, forming a fixed structure with the positioning member 30 with both ends clamping, which can further reduce the bending moment of the welding point 20.

[0037] Furthermore, the positioning element 30 is detachably connected to the fixed base 13. The detachable connection between the positioning element 30 and the fixed base 13 can be achieved by using structures or components such as snaps, bolts, slides, or pin-type interfaces. The detachable connection of the positioning element 30 to the fixed base 13 allows the connection position of the positioning element 30 to be adjusted according to the position of the welding point 20. When the positioning element 30 ages and fails, it can also be replaced individually.

[0038] Secondly, this utility model provides a stator assembly, including a stator body and the aforementioned stator busbar structure, with stator windings wound around the stator body. The stator busbar structure can serve as an integrated conductive module of the stator assembly, capable of collecting the three-phase current generated by the stator windings with low impedance and leading it to an external controller. Simultaneously, through the coordinated constraint of the positioning member 30 and the fixing seat 13, it imparts vibration resistance to the welding point 20.

[0039] The aforementioned stator bus structure ensures that the stator assembly maintains the metallurgical integrity and electrical continuity of the welded points even in the high-frequency vibration environment of the gearbox, achieving maintenance-free and highly reliable current transmission throughout the entire path.

[0040] Thirdly, this utility model provides a motor including the aforementioned stator assembly. Because the stator assembly includes a stator busbar structure, the motor maintains the metallurgical integrity and electrical continuity of the welded joints 20 even under high-frequency vibration conditions of the vehicle's transmission, achieving maintenance-free operation and highly stable power output throughout its entire lifecycle.

[0041] The above description, based on the embodiments shown in the drawings, details the structure, features, and effects of this utility model. The above description is only a preferred embodiment of this utility model, but the scope of implementation of this utility model is not limited to what is shown in the drawings. Any changes made in accordance with the concept of this utility model, or modifications to equivalent embodiments, that do not exceed the spirit covered by the specification and drawings, shall be within the protection scope of this utility model.

Claims

1. A stator busbar structure, characterized in that, include: Stator winding, the stator winding having lead-out terminals; A busbar assembly having a conductive part, the conductive part being welded to the output terminal, and a welding point being formed at the welding point between the conductive part and the output terminal; A positioning element, which is used to fix the output end and the conductive part.

2. The stator busbar structure according to claim 1, characterized in that, The positioning element has a positioning space, and both the conductive part and the output end extend through the positioning space.

3. The stator busbar structure according to claim 2, characterized in that, The positioning element includes a positioning block, and the positioning block is provided with a positioning hole. The positioning hole is disposed through the positioning block, and the space inside the positioning hole forms the positioning space.

4. The stator busbar structure according to claim 3, characterized in that, The positioning element further includes a positioning seat, and the positioning blocks include a plurality of them, which are spaced apart from each other on the positioning seat.

5. The stator busbar structure according to claim 1, characterized in that, The bus assembly includes a hard copper busbar, which includes a conductive portion and a lead-out terminal. The hard copper busbar extends along a conductive path from the conductive portion to the lead-out terminal.

6. The stator busbar structure according to claim 5, characterized in that, The lead-out end is provided with a connection terminal, and the connection terminal is provided with a bolt hole. The bolt hole is used for conductive connection with the controller to transmit the current of the hard copper busbar to the controller.

7. The stator busbar structure according to claim 1, characterized in that, The stator bus structure also includes a mounting base, on which the bus assembly is mounted.

8. The stator busbar structure according to claim 7, characterized in that, The positioning element is detachably connected to the fixing base.

9. A stator assembly, comprising a stator body, characterized in that, The stator assembly further includes the stator bus structure according to any one of claims 1 to 8; The stator winding is wound around the stator body.

10. An electric motor, characterized in that, Includes the stator assembly as described in claim 9.

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