Stator for an electric drive machine, electric drive machine having such a stator, and motor vehicle

Abstract

The invention relates to a stator (10) for an electric drive machine (100) of a motor vehicle (K), comprising at least one bus bar (20) which is provided for transmitting electrical energy to a winding assembly of the stator (10) and which, at least in parts, has a polygonal bus bar cross-section (30) which is oriented perpendicularly to a main extent direction (H) of the bus bar (20) and which has at least one first bus bar cross-sectional side (32) and at least one second bus bar cross-sectional side (34). The at least one first bus bar cross-sectional side (32) is shorter than the at least one second bus bar cross-sectional side (34), and the bus bar (20) has a deformation region (40) which comprises deformed lamination portions (42) and which is deformed at least in parts about a deformation straight line (60) oriented at least substantially parallel to the first bus bar cross-sectional side (32). Further aspects of the invention relate to an electric machine (100) having a stator (10), and to a motor vehicle (K).

Description

[0001] Stator for an electric drive motor, electric drive motor with such a stator and motor vehicle

[0002] The invention relates to a stator for an electric drive motor according to the preamble of claim 1. Further aspects of the invention relate to an electric drive motor with such a stator and to a motor vehicle.

[0003] Busbars, also known as busbars, are typically used to transmit electrical energy between an inverter and a stator. These high-voltage components are often made of stamped and bent copper parts. Due to the high currents in electric vehicles, these busbars have massive cross-sections and are therefore designed to be highly rigid. To maintain at least a certain degree of freedom within the relevant functional chains, flexible busbars are often employed.

[0004] For example, DE 102022 209 751 A1 discloses a connection device for electrically connecting a power converter to an electric machine for an electric axle drive of a motor vehicle, wherein the connection device comprises at least one busbar made of an electrically conductive material. The at least one busbar has a first connection section and a second connection section located away from the first connection section. The first connection section is shaped for electrical connection to the power converter. Furthermore, at least one woven strip is provided, which is flexibly formed (for example, by weaving) from an electrically conductive material. The at least one woven strip has a first end and a second end located away from the first end. The first end is shaped for a material-bonded connection with the second connection section of the at least one busbar.The second end is shaped for electrical connection to the electric machine. Furthermore, a housing unit made of an electrically insulating material is provided, which is shaped to accommodate the at least one busbar between the first connection section and the second connection section. The object of the present invention is to provide a stator, an electric drive machine, and a motor vehicle of the type mentioned above, in which improved tolerance compensation is achieved with a small installation space.

[0005] This problem is solved by a stator with the features of claim 1, by an electric drive machine with the features of claim 9, and by a motor vehicle according to claim 10. Advantageous embodiments with expedient further developments of the invention are specified in the dependent claims.

[0006] A first aspect of the invention relates to a stator for an electric drive motor of a motor vehicle, comprising at least one busbar for transmitting electrical energy to a winding arrangement of the stator and having, at least in some areas, a polygonal busbar cross-section oriented perpendicular to a principal direction of extension of the busbar, which has at least a first busbar cross-section side and at least a second busbar cross-section side. The busbar can also be referred to as a busbar, phase connection busbar, or star point busbar.

[0007] According to the invention, it is provided that the at least one first busbar cross-sectional side is shorter than the at least one second busbar cross-sectional side and that the busbar has a deformation area comprising sheet metal deformations, which is deformed at least partially around a deformation line oriented at least substantially parallel to the first busbar cross-sectional side.This is advantageous because the deformation area is thus deformed at least largely, though not exclusively, between two planes oriented parallel to the second conductor rail cross-section and adjacent to the conductor rail, the distance of which corresponds at least substantially to the length of the first conductor rail cross-section, and accordingly requires very little installation space during its deformation, especially in contrast to a possible bending around a second deformation line oriented at least substantially parallel to the second conductor rail cross-section, since the latter involves a significantly larger three-dimensional space requirement than the deformation area according to the invention.The deformation in the deformation area may, at most, result in the formation of slight bulges, through which the busbar protrudes slightly from the space between the planes mentioned above. The sheet metal deformations can preferably be designed as at least one compression and / or at least one elongation of the deformation area, which are advantageously producible with less deformation work than components with larger wall thicknesses, for example, more than 3 mm to 4 mm, where a plate, rather than a sheet, is used.

[0008] The expression "at least substantially parallel" also includes a slight deviation of up to an angle of 10°. This expression also includes a skew orientation of the deformation line relative to the first conductor rail cross-section, where an angle of this magnitude is involved. In the case of a skew arrangement, it is assumed that the angle between two skew lines, one of which runs along the first conductor rail cross-section and the other corresponding to the deformation line, is the angle of intersection of two mutually intersecting lines that are parallel to the given skew first and second lines, respectively.Provided that the magnitude of this angle of intersection is also up to 10°, the first line to the second line and thus the deformation line to the first conductor rail cross-section side are to be understood as at least substantially parallel within the meaning of the present disclosure.

[0009] The busbar cross-section can preferably be rectangular, which allows for particularly well-defined, and especially uniform, deformations. Furthermore, the rectangular cross-section can be manufactured with minimal effort and contributes to a particularly compact, space-saving design of the busbar.

[0010] The deformation zone can exhibit elastic and / or plastic deformations. While elastic deformations result in smaller material accumulations, particularly material bulges, that occupy less space and are caused by the deformation itself, compared to plastic deformations, plastic deformations exert less or no mechanical stress on components connected to the deformation zone. A particularly advantageous compromise is achieved when the deformation zone exhibits both elastic and plastic deformations.

[0011] The invention is based on the general understanding that the deformation range allows for advantageous adherence to functional dimension chains that must be considered during stator assembly. When coupled to an inverter of the electric drive motor or the vehicle, the deformation range of the busbar enables effective compensation of tolerances without requiring space-consuming, three-dimensional deformation of the busbar. Furthermore, sheet metal sheets subjected to deformation exhibit a lower specific resistance for the same installation space than, for example, wire meshes known from the prior art for compensating tolerances.A key advantage of the invention is that, due to the small installation space requirement, particularly the small three-dimensional space requirement, of the deformation area, many high-voltage conductive elements can be accommodated in a confined space adjacent to the busbar without undesirable contact between the busbar and these elements. The busbar, in particular, enables these elements to comply with different, sometimes divergent, tolerance requirements. This invention disclosure describes an embodiment of the flexible busbar in the deformation area, in which the conductor section represented by the flexible deformation area, unlike conventional solutions, is not bent around a long cross-sectional edge, but rather deformed around at least the first side of the busbar cross-section, i.e., around a narrow edge of the polygonal busbar cross-section.This makes it possible to respond to sensitive installation space requirements while minimizing additional manufacturing effort.

[0012] In an advantageous embodiment of the invention, the at least one busbar comprises a plurality of interconnected, current-conducting individual laminations, at least in the deformation area. This is advantageous because the interconnected individual laminations represent a good compromise between low-effort deformation and low electrical resistance, particularly compared to wire braids. The individual laminations can preferably be stacked one above the other in such a way that the thicknesses of the individual laminations together form the first cross-sectional side of the busbar, and at least one outermost lamination of the plurality of individual laminations forms the at least one second cross-sectional side of the busbar.

[0013] The at least one busbar can be formed, at least in the deformation zone, by a plurality of interconnected individual laminations. These individual laminations can be joined together by welds, creating a material bond. The welds can preferably be spot welds, allowing for low-effort deformation of the individual laminations and relative deformation between them during the formation of the deformation zone with minimal force. This enables, for example, the creation of opposing compressions and elongations with minimal effort.

[0014] In a further advantageous embodiment of the invention, the deformation area comprises a compression zone facing the deformation line and an expansion zone facing away from the deformation line. This is advantageous because the compression and expansion zones form respective deformation zones that allow for simple tolerance compensation during the assembly of the busbar without resulting in significant three-dimensional deformations and material accumulation. In the compression zone, the deformation area can be compressed, i.e., exhibit compressions, particularly compressions of the individual plates. In the expansion zone, the deformation area can be stretched, i.e., exhibit expansions, particularly expansions of the individual plates.

[0015] In a further advantageous embodiment of the invention, the deformation area at the compression zone has a first deformation which extends more perpendicular to the main direction of extension of the busbar than a second deformation associated with the expansion zone. An advantage here is that the first and second deformations require only a small amount of three-dimensional installation space. The first deformation and / or second deformation can also be referred to as the first loft and / or second loft, or the first material loft and / or second material loft.

[0016] In a further advantageous embodiment of the invention, at least one busbar has an insulating area adjacent to the deformation zone, in which the busbar has electrical insulation. This is advantageous because it provides electrical insulation as required. This prevents flashover, in particular sparking, even if a minimum distance between the busbar and another electrically conductive element of the stator or the electric drive motor is not maintained.

[0017] In a further advantageous embodiment of the invention, the at least one busbar is designed to be at least partially insulation-free in the deformation area. This enables electrical contact and facilitates deformation, in particular bending, in the deformation area. In a further advantageous embodiment of the invention, the at least one busbar has a current-conducting insulation core formed from solid material in the insulation area. This is advantageous because it provides a targeted increase in stiffness compared to the deformation area. The deformation area and the insulation area can be directly connected to each other, for example, by a material bond. For example, the insulation core of the insulation area can be electrically connected to the deformation area, in particular to the current-conducting individual sheets of the deformation area, in a material bond.Preferably, the insulation area, in particular the insulation area core, and the deformation area can be welded together, thus ensuring high durability.

[0018] In a further advantageous embodiment of the invention, the at least one busbar has an inverter connection at the deformation area, via which the at least one busbar can be electrically coupled to an inverter of the motor vehicle or the electric drive motor. This enables direct electrical contact between the busbar and the inverter, whereby the deformation area can be deformed depending on tolerance requirements.

[0019] A second aspect of the invention relates to an electric drive motor with at least one stator according to the first aspect of the invention. Such an electric drive motor offers improved tolerance compensation while requiring minimal installation space.

[0020] A third aspect of the invention relates to a motor vehicle with an electric drive motor according to the second aspect of the invention and additionally or alternatively with a stator according to the first aspect of the invention. Such a motor vehicle offers improved tolerance compensation with a limited installation space.

[0021] The preferred embodiments and their advantages presented with respect to one of the aspects apply accordingly to the other aspects of the invention and vice versa.

[0022] The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combination specified in each case, but also in other combinations or on their own, without leaving the scope of the invention.

[0023] Further advantages, features and details of the invention will become apparent from the claims, the following description of preferred embodiments and the drawings.

[0024] The invention is explained below again using a specific embodiment. This is illustrated by:

[0025] Fig. 1 shows a schematic perspective view of a busbar of an abstractly represented stator of an also abstractly represented electric drive machine of a motor vehicle;

[0026] Fig. 2 shows another schematic perspective view of the busbar from a viewing direction opposite to that of Fig. 1;

[0027] Fig. 3 shows a schematic side view of the busbar and

[0028] Fig. 4 shows a top view of the busbar.

[0029] Fig. 1 shows in abstract form a motor vehicle K with an electric drive machine 100, also shown in abstract form. The drive machine 100 serves as the traction machine of the motor vehicle K and, in addition to a rotor (not shown), has, for example, a stator 10 (also shown in abstract form) with a busbar 20.

[0030] The busbar 20 is intended for the transmission of electrical energy to a winding arrangement of the stator 10 (not shown).

[0031] Fig. 1 illustrates that the busbar 20 has a polygonal busbar cross-section 30 oriented perpendicular to a main extension direction H of the busbar 20 shown in Figs. 3 and 4. The busbar cross-section 30 is designed as a rectangular cross-section and has two opposing first busbar cross-section sides 32 and two opposing second busbar cross-section sides 34. The first busbar cross-section sides 32 are shorter than the second busbar cross-section sides 34. The first busbar cross-section sides 32 form narrow surfaces of the busbar 20, whereas the second busbar cross-section sides 34 form wide surfaces of the busbar.

[0032] The busbar 20 also has a deformation area 40 comprising sheet metal deformations 42, which is partially deformed around a deformation line 60 oriented parallel to the first busbar cross-sectional sides 32 and is thereby bent around the deformation line 60. The special feature of the busbar 20 is therefore that it is bent around the deformation line 60 at the narrow surfaces.

[0033] The busbar 20 has a plurality of interconnected, electrically conductive individual sheets 44, 46 at the deformation zone 40. These sheets are stacked on top of each other and spot-welded together, allowing them to be readily deformable despite their interconnection. The sheet deformations 42 are formed by the elastically or plastically deformed individual sheets 44, 46. The individual sheets 42, 44 form a plurality of stacked, thin individual copper sheets, which are interconnected by end-to-end welding (for example, by laser or ultrasonic welding) and together, in their undeformed state, exhibit the polygonal busbar cross-section 30 (here: rectangular cross-section). The polygonal busbar cross-section 30 allows for mechanical flexibility in the deformation zone 40.

[0034] The deformation area 40 comprises, on the one hand, a compression zone 56, which faces the deformation line 60, and on the other hand, an expansion zone 58, which faces away from the deformation line 60.

[0035] The deformation zone 40 exhibits a first deformation 57 at the compression zone 56, which has a greater extent E1 perpendicular to the main extension direction H than a second deformation 59 associated with the strain zone 58. The second deformation 59 has a second extent E2, the length of which is correspondingly smaller than extent E1. The deformations 57 and 59 form respective material protrusions, also called material distortions, which, however, have a small three-dimensional extent and therefore allow for tolerance compensation by means of the busbar 20 even with limited available installation space. The second extent E2 is shown in Fig. 1, whereas extent E1 is shown in Fig. 2. The busbar 20 also has an insulation zone 70 adjacent to the deformation zone 40, in which the busbar 20 has electrical insulation 72.For clarity, the insulation area 70 with the insulation 72 is only schematically shown in Fig. 4. The busbar 20 has a current-conducting insulation core 74 formed from solid material at the insulation area 70, which also has the polygonal busbar cross-section 30. The insulation core 74 is directly or indirectly electrically connected to the deformation area 40, in particular by a material bond, for example by welding. Due to a breakout in the insulation area 70 shown in Fig. 4, the insulation core 74 is partially exposed and thus visible. The insulation 72 can be designed as an overmolding of the insulation area 70, thereby circumferentially surrounding the insulation core 74, and is preferably made of plastic.

[0036] The busbar 20 is designed without insulation at the deformation zone 40 and has an inverter connection 50 at the deformation zone 40, via which the busbar 20 is conductively coupled to an inverter (not shown) of the vehicle K or the electric drive 100. The busbar 20 is connected via the inverter connection 50 to a high-voltage terminal block 12 or a plurality of high-voltage terminal blocks 12, 14 of the stator 20 or the electric drive 100. Due to the flexibility of the busbar 20, a functional dimensional chain between the stator 10 and the inverter can be maintained in a simplified manner.

[0037] The present busbar 20 allows tolerances to be compensated for and takes into account demanding installation space requirements in the electric drive machine 100.

[0038] While known busbar components are realized as copper stamped and bent parts, which are designed with massive cross-sections due to high currents and are therefore rigid, the flexibility of the present busbar 20 creates increased degrees of freedom in the functional dimension chain, whereby the deformation range 40 provides mechanical mobility in the otherwise rigid busbar 20.

[0039] The busbar 20 is particularly suitable for use alongside many high-voltage conductive elements, such as the high-voltage connection domes 12, 14, especially when several conductors have to be accommodated in a confined space and meet diverging tolerance requirements.

[0040] The busbar 20 makes it possible to respond to sensitive installation space requirements, while simultaneously minimizing additional manufacturing effort compared to conventional busbar systems.

[0041] Reference symbol list

[0042] 10 Stator

[0043] 12 high-voltage connection dome

[0044] 14 High-voltage connection dome

[0045] 20 busbar

[0046] 30 busbar cross-section

[0047] 32 first busbar cross-section side

[0048] 34 second busbar cross-section side

[0049] 40 Deformation range

[0050] 42 Sheet metal forming

[0051] 44 individual sheets

[0052] 46 individual sheets

[0053] 50 Inverter connection

[0054] 56 Compression zone

[0055] 57 first deformation

[0056] 58 Stretch zone

[0057] 59 second deformation

[0058] 60 Deformation lines

[0059] 70 Insulation area

[0060] 72 Insulation

[0061] 74 Insulation area core

[0062] 100 electric drive motors

[0063] E1 extension

[0064] E2 second extension

[0065] H Main direction of extension

[0066] K motor vehicle

Claims

Claims 1. Stator (10) for an electric drive machine (100) of a motor vehicle (K), with at least one conductor rail (20) which is provided for the transmission of electrical energy to a winding arrangement of the stator (10) and which has at least partially a polygonal conductor rail cross-section (30) oriented perpendicular to a main extension direction (H) of the conductor rail (20), which has at least a first conductor rail cross-section side (32) and at least a second conductor rail cross-section side (34), characterized in that the at least one first conductor rail cross-section side (32) is shorter than the at least one second conductor rail cross-section side (34) and the conductor rail (20) has a deformation area (40) comprising sheet metal deformations (42), which is deformed at least partially around a deformation line (60) oriented at least substantially parallel to the first conductor rail cross-section side (32).

2. Stator (10) according to claim 1, characterized in that the at least one busbar (20) has at least in the deformation area (40) a plurality of interconnected, current-conducting individual laminations (44, 46).

3. Stator (10) according to claim 1 or 2, characterized in that the deformation area (40) has a compression zone (56) which faces the deformation line (60) and an expansion zone (58) which faces away from the deformation line (60).

4. Stator (10) according to claim 3, characterized in that the deformation area (40) at the compression zone (56) has a first deformation (57) which has a greater extent (E1) perpendicular to the The main extension direction (H) includes a second deformation (59) associated with the extension zone (58).

5. Stator (10) according to one of the preceding claims, characterized in that the at least one busbar (20) has an insulation area (70) adjacent to the deformation area (40), in which the busbar (20) has electrical insulation (72).

6. Stator (10) according to claim 5, characterized in that the at least one busbar (20) is designed to be at least partially insulation-free at the deformation area (40).

7. Stator (10) according to claim 5 or 6, characterized in that the at least one busbar (20) has a current-conducting insulation core (74) formed from solid material at the insulation area (70).

8. Stator (10) according to one of the preceding claims, characterized in that the at least one busbar (20) has an inverter connection (50) at the deformation area (40), via which the at least one busbar (20) can be coupled to an inverter of the motor vehicle (K) or the electric drive machine (100) in a current-conducting manner.

9. Electric drive machine (100) with at least one stator (10) according to one of the preceding claims.

10. Motor vehicle (K) with an electric drive motor (100) according to claim 9 and / or with a stator (10) according to one of claims 1 to 8.

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