Stator assembly, flat wire motor and vehicle power assembly

Abstract

The invention provides a stator assembly, a flat wire motor and a vehicle power assembly, and relates to the technical field of stator assembly design, and the stator assembly comprises a stator core which is provided with a plurality of stator grooves; the stator winding comprises a multi-phase winding arranged on the stator core, and a plurality of layers are formed on each stator slot; wherein each phase winding comprises a plurality of coils, and the plurality of coils are arranged in the stator slots in a layered manner along the radial direction of the stator core; on the crown side, the coil is provided with a bending part close to the stator iron core; in at least one stator slot, coils of adjacent layers belong to different-phase windings, and bending parts of two coils which belong to different-phase windings and are adjacent layers are arranged in a staggered manner along the axial direction of the stator core. According to the invention, the insulation risk of short-distance winding of the stator can be effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of stator assembly design, and in particular to a stator assembly, a flat wire motor, and a vehicle powertrain. Background Art

[0002] When a flat-wire motor uses a short-pitch stator winding scheme, a single stator slot may contain coils of different phases. However, because the copper wire ends of the coils protruding from the core end face on the crown side are bent along the width, their thickness increases, thereby reducing the radial clearance. This design can significantly increase the risk of motor insulation failure. Summary of the Invention

[0003] The main purpose of the present invention is to provide a stator assembly, aiming to reduce the insulation risk of short-pitch stator windings.

[0004] To achieve the above object, the present invention provides a stator assembly for a flat wire motor, the stator assembly comprising:

[0005] a stator core, wherein the stator core has a plurality of stator slots;

[0006] a stator winding comprising a multi-phase winding mounted on the stator core and formed in multiple layers on each of the stator slots;

[0007] Wherein, each phase of the winding includes a plurality of coils, and the plurality of coils are layered and arranged in the stator slots along the radial direction of the stator core;

[0008] On the crown side, the coil has a bent portion close to the stator core; in at least one stator slot, there are coils of adjacent layers belonging to different phase windings, and the bent portions of the two coils belonging to different phase windings and adjacent layers are staggered in position along the axial direction of the stator core.

[0009] Optionally, each of the coils is arranged at an outlet end of the stator slot perpendicular to an axial end surface of the stator core.

[0010] Optionally, the bent portion of the outermost coil in the same stator slot is arranged closer to the axial end surface of the stator core than the bent portion of the second outermost coil.

[0011] Optionally, the bent portion of the innermost coil in the same stator slot is arranged closer to the axial end surface of the stator core than the bent portion of the next innermost coil.

[0012] Optionally, each of the coils has a first bent portion and a second bent portion, and the first bent portion and the second bent portion are close to the stator core;

[0013] The first bent portion is arranged closer to the axial end surface of the stator core than the second bent portion; and the crown top on the crown side is arranged closer to the second bent portion.

[0014] Optionally, the radius of the inner fillet of the bending portion is 1-1.2 times the line width of the coil.

[0015] Optionally, the bent portion of the outermost coil in the same stator slot is arranged closer to the axial end surface of the stator core than the bent portion of the second outermost coil.

[0016] Optionally, the bent portion of the innermost coil in the same stator slot is arranged closer to the axial end surface of the stator core than the bent portion of the next innermost coil.

[0017] In addition, to achieve the above-mentioned object, the present invention also provides a flat wire motor, comprising the stator assembly as described above.

[0018] In addition, to achieve the above-mentioned purpose, the present invention also provides a vehicle powertrain, including the flat wire motor as described above.

[0019] This application proposes a stator assembly comprising a stator core and a stator winding. The stator core has a plurality of stator slots. The stator winding comprises a multi-phase winding mounted on the stator core, with multiple layers formed in each stator slot. Each phase winding comprises multiple coils, which are arranged in layers in the stator slots along the radial direction of the stator core. Each coil has a crown side extending out of the stator core, and each coil's crown side has a bent portion proximate to the stator core. In at least one stator slot, coils in adjacent layers belong to different phases. By staggering the bent portions of two coils belonging to different phases and adjacent layers along the axial direction of the stator core, the insulation risk of short-spacing stator windings can be effectively reduced. Compared to the prior art, the staggered bent portions of adjacent coils of different phases can be staggered as the thickness of the bent portions increases, preventing the radial gap between the bent portions at a height close to the end face of the stator core from decreasing as the coil thickness increases, thereby significantly reducing the risk of insulation failure in the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 1 is a schematic structural diagram of a stator assembly according to an embodiment of the present invention;

[0023] Figure 2 for Figure 1 A schematic cross-sectional structural diagram of a stator assembly;

[0024] Figure 3 for Figure 2 A magnified schematic diagram of the structure of the middle part B;

[0025] Figure 4 for Figure 2 A schematic diagram of the structure of the middle part A;

[0026] Figure 5 This is a schematic structural diagram of a stator assembly according to another embodiment of the present invention;

[0027] Figure 6 This is a schematic structural diagram of a stator assembly according to another embodiment of the present invention;

[0028] Figure 7 for Figure 6 A magnified schematic diagram of the structure of the middle C section;

[0029] Figure 8 This is a coil phase sequence distribution diagram of the stator assembly of the present invention.

[0030] Description of Figure Numbers:

[0031] Label name Label name 10 stator core 32 Bending section 20 stator slots 321 First bending part 30 Coil 322 Second bending part 31 Crown side - -

[0032] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and the well-known modules, units and their connections, links, communications or operations are not shown or described in detail. In addition, the described features, architectures or functions can be combined in any way in one or more embodiments. It should be understood by those skilled in the art that the various embodiments described below are only for illustration and are not intended to limit the scope of protection of the present invention. It can also be easily understood that the modules or units or processing methods in the various embodiments described herein and shown in the drawings can be combined and designed according to various different configurations. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0034] The definitions of various nouns or methods in the following embodiments, except for those that are logically untenable, are generally based on the broad concepts that can be implemented under the premise of the disclosure in the embodiments. Under such understanding, the various specific subordinate specific definitions of the nouns or methods should be regarded as the inventive content of the present invention, and should not be narrowly understood or interpreted in a biased manner on the grounds that the specification does not disclose such specific definitions. Similarly, under the premise that it can be logically implemented, the order of the steps in the method is flexible and changeable, and the specific subordinate specific definitions in the broad concepts of various nouns or methods all fall within the scope of protection of the present invention.

[0035] When a flat-wire motor uses a short-pitch stator winding scheme, a single stator slot may contain coils of different phases. However, because the copper wire ends of the coils protruding from the core end face on the crown side are bent along the width, their thickness increases, thereby reducing the radial clearance. This design can significantly increase the risk of motor insulation failure.

[0036] It should be noted that when the flat wire motor is a short-pitch motor, a stator slot may contain coils of different phases, such as AAABBB type, ABABAB type or AABBAA type, etc. The coils of existing flat wire motors are mostly realized by using hairpin coils, for example Figure 5 and Figure 6 As can be seen from the hairpin coil structure in the figure, it needs to be bent on both sides to form two straight segments during production, which will increase the thickness of the bend. After multiple hairpin coils are inserted into the stator core, for example Figure 1 and Figure 2 As shown in , if adjacent coils do not belong to the same phase winding, the bends that are close to each other may contact each other due to the increase in thickness, thus causing the motor insulation to fail. Figure 8 , Figure 8 The stator winding shown is of ABABAB type structure, combined with Figure 8 and Figure 1 Taking stator slot A as an example, the coils in the first and second layers belong to windings of different phases. For example, the first layer is U-phase and the second layer is V-phase. Then, on the stator winding, for the coils in adjacent layers of the slot, if their height relative to the core end face is close to the bend, if the thickness is too large and causes contact between the two sides, then insulation failure will occur between the U-phase and the V-phase, which will have a great impact on the stability and safety of the motor.

[0037] In order to solve the above problems, the present application proposes a stator assembly. Figures 1 to 3 In one embodiment of the present invention, the stator assembly includes a stator core 10, stator slots 20, and stator windings, wherein:

[0038] The stator core 10 has a plurality of stator slots 20; the stator winding includes a multi-phase winding installed on the stator core 10, and multiple layers are formed on each of the stator slots 20; wherein, each phase of the winding includes a plurality of coils 30, and the plurality of coils 30 are layered in the stator slots 20 along the radial direction of the stator core 10, and on the crown side 31, the coils 30 have a bent portion 32 close to the stator core 10; in at least one stator slot 20, there are adjacent layers of coils 30 belonging to different phase windings, and the bent portions 32 of the two coils 30 belonging to different phase windings and adjacent layers are staggered in position along the axial direction of the stator core 10.

[0039] In this embodiment, a plurality of coils 30 are sequentially arranged in the stator slots 20 from the inside of the stator core 10 to the outside, with the coil closest to the inside of the stator core 10 being the first layer. Alternatively, a plurality of coils 30 may be sequentially arranged from the outside of the stator core 10 to the inside, with the coil closest to the outside of the stator core 10 being the first layer.

[0040] Among them, the bending portions 32 of the two coils 30 belonging to different phase windings and adjacent layers are staggered. For example, if the coils 30 in the stator slots 20 are of AAABBB type, the bending portions 32 of the coils 30 in the third and fourth layers are staggered. Figure 3In the example shown, for example, the A coil 30 of the third layer is arranged closer to the axial end face of the stator core 10 than the B coil 30 of the fourth layer. Compared with the prior art, the bending portion 32 of the prior art is arranged flush. When the thickness dimension increases, the thickness dimensions of the two adjacent coils 30 will increase, resulting in a significant reduction in the radial gap. However, with the staggered arrangement of this embodiment, although the thickness dimension of the coil 30 will still increase, the bending portions 32 of the adjacent coils 30 will not be at a height close to the end face of the stator core as in the prior art, thereby effectively avoiding the reduction of the radial gap and effectively reducing the risk of insulation failure caused by the phase difference between different phase windings.

[0041] In this embodiment, multiple coils 30 are layered in the stator slots 20 along the radial direction of the stator core 10. Each coil 30 has a crown side 31 extending from the stator core 10, and the crown side 31 has a bent portion 32 proximate to the stator core 10. Furthermore, in at least one stator slot 20, adjacent layers of coils 30 belong to different phase windings. Thus, by staggering the bent portions 32 of two coils 30 belonging to different phase windings and adjacent layers along the axial direction of the stator core 10, the insulation risk of short-pitch stator windings can be effectively reduced. Compared to the prior art, the bent portions of adjacent coils of different phases can be staggered as the thickness of the bent portion 32 increases. This prevents the radial gap between the bent portions at a height close to the stator core end face from decreasing as the coil thickness increases, thereby significantly reducing the risk of insulation failure in the motor.

[0042] Optionally, refer to Figure 4 Another embodiment of the present invention provides a stator assembly, based on the above Figure 1 In the illustrated embodiment, each coil 30 is disposed at the outlet end of the stator slot 20 perpendicular to the axial end surface of the stator core 10 .

[0043] In this embodiment, by being arranged perpendicular to the axial end face of the stator core 10, mutual interference with adjacent coils 30 can be reduced, thereby achieving a more compact coil 30 layout in the stator slot 20, effectively simplifying the assembly process of the coil 30, and reducing production costs.

[0044] It should be understood that, based on the arrangement of the outlet end of the stator slot 20 being perpendicular to the axial end face of the stator core 10, as shown in FIG. Figure 4 As shown, the bent portion 32 of the outermost coil 30 in the same stator slot 20 is closer to the axial end surface of the stator core 10 than the bent portion 32 of the second outermost coil 30 .

[0045] In other words, the distance from the bent portion 32 of the outermost coil 30 in the same stator slot 20 to the axial end surface of the stator core 10 is smaller than the distance from the bent portion 32 of the next outermost coil 30 to the axial end surface of the stator core 10 .

[0046] Multiple coils 30 are arranged sequentially from the outside of the stator core 10 to the inside. The coils 30 closest to the outside of the stator core 10 are designated as the first layer, and the coils 30 further inward are designated as the second layer. Assuming that the coils 30 in the first and second layers belong to different phase windings, the protruding portion of the coils 30 in the outermost layer can extend outward from the stator core 10 due to the larger space available on the outermost side. This allows the coils 30 in the first layer to be positioned closer to the axial end face of the stator core 10, forming a pattern with a lower outer portion and a higher inner portion. This allows the bent portion 32 of the coils 30 in the second layer to be more easily extended outward, thereby effectively preventing an excessive reduction in the radial clearance. Furthermore, to further reduce the risk of insulation failure, when the coils 30 in the first and second layers are staggered, with the first layer closer to the axial end face of the stator core 10, the bent portion 32 of the coils 30 in the second layer can be tilted outward toward the first layer within a certain range to increase the radial clearance.

[0047] It should be understood that, similar to the arrangement of the outermost coil 30 and the second outermost coil 30 mentioned above, the bending portion 32 of the innermost coil 30 located in the same stator slot 20 is arranged closer to the axial end face of the stator core 10 than the bending portion 32 of the second innermost coil 30.

[0048] In other words, the distance from the bent portion 32 of the innermost coil 30 in the same stator slot 20 to the axial end surface of the stator core 10 is smaller than the distance from the bent portion 32 of the next innermost coil 30 to the axial end surface of the stator core 10 .

[0049] Multiple coils 30 are arranged sequentially from the inside of the stator core 10 to the outside. The coils 30 closest to the inside of the stator core 10 are designated as the first layer, and the coils 30 one layer further out are designated as the second layer. Assuming that the coils 30 in the first and second layers belong to different phase windings, the protruding portion of the coils 30 in the innermost layer can extend outward from the stator core 10 due to the larger space available on the innermost side. This allows the coils 30 in the first layer to be positioned closer to the axial end face of the stator core 10, forming a lower-inner-higher-outer pattern. This allows the bent portion 32 of the second layer coil 30 to more easily extend inward from the stator core 10, thereby effectively preventing an excessive reduction in the radial clearance. Furthermore, to further reduce the risk of insulation failure, when the first and second layers of coils 30 are staggered, with the first layer coil 30 positioned closer to the axial end face of the stator core 10, the bent portion 32 of the second layer coil 30 can be tilted toward the first layer coil 30 within a certain range to increase the radial clearance. Through this design, a more efficient layout of the coil 30 can be achieved within a limited space.

[0050] Optionally, refer to Figure 5 Another embodiment of the present invention provides a stator assembly, based on the above Figure 1 In the embodiment shown, each of the coils 30 has a first bending portion 321 and a second bending portion 322, and the first bending portion 321 and the second bending portion 322 are close to the stator core 10; wherein the first bending portion 321 is arranged closer to the axial end face of the stator core 10 than the second bending portion 322; and the crown top of the crown side 31 is arranged close to the second bending portion 322.

[0051] In this embodiment, the distance between the lowest point of the first bend 321 and the axial end face of the stator core 10 is H1, and the distance between the lowest point of the second bend 322 and the axial end face of the stator core 10 is H2. Since the same coil 30 has two bends 32, if the two bends 32 are at the same distance from the axial end face of the stator core 10, the crown of the crown side 31 will be in the middle position. However, since H1 is smaller than H2, the distance between the two bends 32 and the axial end face of the stator core 10 is inconsistent. If the crown of the crown side 31 is at the middle position, the distance between the crown of the crown side 31 and the axial end face of the stator core 10 will be too large, thereby affecting the compact layout of the coil 30. Figure 5 As shown, the distance between the first bend portion 321 and the crown of the crown side 31 is L1, and the distance between the second bend portion 322 and the crown of the crown side 31 is L2. In order to balance the distance between the crown of the crown on the crown side 31 and the axial end face of the stator core 10, by making L1 greater than L2, the crown of the crown side 31 is arranged toward the second bend portion 322 farther from the axial end face of the stator core 10, so that the overall layout of the coil 30 is more compact.

[0052] It should be understood that when the inner fillet of the bend 32 is too small, stress concentration will occur in the coil 30, thereby increasing the risk of damage to the coil 30. When the inner fillet of the bend 32 is too large, the distance between the crown top of the crown side 31 of the coil 30 and the axial end face of the stator core 10 will be too large, causing the overall motor to be too large.

[0053] Optionally, refer to Figure 6 and Figure 7 Another embodiment of the present invention provides a stator assembly based on the above Figure 1 In the illustrated embodiment, the radius of the inner fillet of the bent portion 32 is 1-1.2 times the wire width of the coil 30 .

[0054] In this embodiment, the fillet radius of the bend 32 is r, and the wire width of the coil 30 is h, with r set to 1h-1.2h. By precisely controlling the fillet radius, stress concentration and the risk of damage to the coil 30 can be effectively avoided while maintaining the compact size of the motor. When the fillet radius is set to 1-1.2 times the wire width of the coil 30, the coil 30 is ensured to avoid stress concentration during the bending process due to an excessively small fillet, while also avoiding unnecessary increase in the overall size of the motor due to an excessively large fillet.

[0055] Optionally, refer to Figure 4 Another embodiment of the present invention provides a stator assembly based on the above Figure 1 In the illustrated embodiment, the bent portion 32 of the outermost coil 30 in the same stator slot 20 is disposed closer to the axial end surface of the stator core 10 than the bent portion 32 of the next outermost coil 30 .

[0056] In this embodiment, multiple coils 30 are arranged sequentially from the outside of the stator core 10 inward. The coils 30 closest to the outside of the stator core 10 are designated as the first layer, and the coils 30 further inward are designated as the second layer. Assuming that the coils 30 in the first and second layers belong to different phase windings, the outermost layer has more space, allowing the protruding portion to extend outward from the stator core 10. Consequently, the coils 30 in the first layer can be positioned closer to the axial end face of the stator core 10, forming a pattern with a lower outer portion and a higher inner portion. This allows the bent portion 32 of the second layer coil 30 to extend outward more easily, thereby effectively preventing an excessive reduction in the radial clearance. Furthermore, to further reduce the risk of insulation failure, when the first and second layers of coils 30 are staggered, with the first layer coil 30 positioned closer to the axial end face of the stator core 10, the bent portion 32 of the second layer coil 30 can be tilted outward toward the first layer coil 30 within a certain range to increase the radial clearance.

[0057] It should be understood that, similar to the arrangement of the outermost coil 30 and the second outermost coil 30 mentioned above, the bending portion 32 of the innermost coil 30 located in the same stator slot 20 is arranged closer to the axial end face of the stator core 10 than the bending portion 32 of the second innermost coil 30.

[0058] In this embodiment, multiple coils 30 are arranged sequentially from the inside of the stator core 10 to the outside. The coils 30 closest to the inside of the stator core 10 are designated as the first layer, and the coils 30 one layer further out are designated as the second layer. Assuming that the coils 30 in the first and second layers belong to different phase windings, the innermost layer has more space, allowing the protruding portion to extend outward from the stator core 10. Consequently, the coils 30 in the first layer can be positioned closer to the axial end face of the stator core 10, forming a lower-inner-higher-outer pattern. This allows the bent portion 32 of the second layer coil 30 to more easily extend inward from the stator core 10, thereby effectively preventing an excessive reduction in the radial clearance. Furthermore, to further reduce the risk of insulation failure, when the first and second layers of coils 30 are staggered, with the first layer coil 30 positioned closer to the axial end face of the stator core 10, the bent portion 32 of the second layer coil 30 can be tilted toward the first layer coil 30 within a certain range to increase the radial clearance. Through this design, a more efficient layout of the coil 30 can be achieved within a limited space.

[0059] The present application also provides a flat wire motor, which includes the stator assembly as described in any one of the above items.

[0060] It is worth noting that since the flat wire motor of the present application includes the above-mentioned stator assembly, the entire technical solution of the flat wire motor of the present application including the stator assembly also has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described in detail here.

[0061] The present application also proposes a vehicle powertrain, which includes the flat wire motor as described in any one of the above items.

[0062] It is worth noting that since the vehicle powertrain of the present application includes the above-mentioned flat wire motor, the vehicle powertrain of the present application includes all technical solutions of the flat wire motor and at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described in detail here.

[0063] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A stator assembly for a flat wire motor, characterized in that: The stator assembly comprises: a stator core, wherein the stator core has a plurality of stator slots; a stator winding comprising a multi-phase winding mounted on the stator core and formed in multiple layers on each of the stator slots; Wherein, each phase of the winding includes a plurality of coils, and the plurality of coils are layered and arranged in the stator slots along the radial direction of the stator core; On the crown side, the coil has a bent portion close to the stator core; in at least one stator slot, there are coils of adjacent layers belonging to different phase windings, and the bent portions of the two coils belonging to different phase windings and adjacent layers are staggered in position along the axial direction of the stator core.

2. The stator assembly according to claim 1, wherein Each coil is arranged at an outlet end of the stator slot and is perpendicular to an axial end surface of the stator core.

3. The stator assembly according to claim 2, wherein: The bent portion of the outermost coil in the same stator slot is closer to the axial end surface of the stator core than the bent portion of the second outermost coil.

4. The stator assembly according to claim 2, wherein: The bent portion of the innermost coil in the same stator slot is closer to the axial end surface of the stator core than the bent portion of the next innermost coil.

5. The stator assembly according to claim 1, wherein: Each of the coils has a first bent portion and a second bent portion, wherein the first bent portion and the second bent portion are close to the stator core; The first bent portion is arranged closer to the axial end surface of the stator core than the second bent portion; and the crown top on the crown side is arranged closer to the second bent portion.

6. The stator assembly according to claim 1, wherein: The radius of the inner fillet of the bending portion is 1-1.2 times the line width of the coil.

7. The stator assembly according to claim 1, wherein: The bent portion of the outermost coil in the same stator slot is closer to the axial end surface of the stator core than the bent portion of the second outermost coil.

8. The stator assembly according to claim 1, wherein: The bent portion of the innermost coil in the same stator slot is closer to the axial end surface of the stator core than the bent portion of the next innermost coil.

9. A flat wire motor, characterized in that: Comprising the stator assembly according to any one of claims 1 to 8.

10. A vehicle powertrain, characterized in that: Comprising the flat wire motor as claimed in claim 9.

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