Stator for an electric machine of a traction drive

Abstract

The present invention relates to a stator (10) for an electric machine of a traction drive of a motor vehicle, wherein the stator (10) comprises an annular stator core (12) having a plurality of slot positions (16), wherein a plurality of plug-in coils (20) are provided, which are arranged in the slot positions (16) passing one another in a hairpin winding technology to form a stator winding (22), and wherein in each slot position (16), an odd number of layers of the plug-in coils (20) are arranged one above the other in the radial direction of the stator core (12), wherein the odd number is ≥ 3, and the plug-in coils (20) are formed by control plug-in coils (20a) and a special plug-in coil (20b), wherein an even number of control plug-in coils (20a) is formed with a layer jump between the slot positions (16) receiving the plug-in coils (20), and a special plug-in coil (20b) is formed without a layer jump between the groove positions (16) receiving the plug-in coil (20).

Description

[0001] The present invention relates to a stator for an electric machine of a traction drive of a motor vehicle. In particular, the present invention relates to a stator having a particularly advantageous winding. The present invention further relates to a traction drive for an electrically driven motor vehicle comprising such a stator, as well as to the use of the advantageous hairpin winding technology for forming a stator winding for a traction drive of an electrically driven motor vehicle.

[0002] Electric motors are a major focus of current developments. These typically consist of a stator and a rotor driven by it. The stator includes a stator winding that can be supplied with current to drive the rotor. Currently, highly automated stator bar-wave windings, such as so-called hairpin windings, are being produced. These have plug-in coils located in the slots of the stator or stator core. Stator windings are usually designed with an even number of layers of plug-in coils in the slots.

[0003] For example, a number of 20 turns can offer advantages. However, manufacturing a number of 20 turns is not trivial. To date, this has usually been achieved using a 10-layer winding with four parallel paths. However, this winding topology is complex to manufacture, so its significance is limited. Furthermore, the ten layers mean that this winding quickly reaches its thermal limit due to the small cross-section of the individual layers, thus limiting the maximum power of the drive system.

[0004] DE 10 2022 120 729 A1 describes a hairpin stator comprising a core, slot positions, and hairpin wires. The core includes a first side and a second side. The slot positions are configured circumferentially on the core to form M radially adjacent slot position layers, where M is an odd number greater than or equal to 5. The hairpin wires are configured in the slot positions and connected to form a plurality of windings. The hairpin wires include a plurality of first U-shaped wires arranged in an outermost slot position layer in the radial direction and a plurality of second U-shaped wires arranged in an innermost slot position layer in the radial direction. Each first U-shaped wire includes a U-shaped portion arranged at the outermost slot position layer and protruding from the first side of the core.Every second U-shaped wire includes a U-shaped portion located at the innermost slot position layer and protruding from the second side of the core.

[0005] However, the state-of-the-art solutions can still be further improved with regard to hairpin winding technology. In particular, there is still room for improvement regarding an easily implementable option for forming a hairpin winding with a highly adaptable number of turns.

[0006] It is therefore the object of the present invention to provide a solution by which at least one disadvantage of the prior art can be at least partially overcome. In particular, it is an object of the present invention to provide a solution by which a hairpin winding can be improved, particularly with regard to the variability of the number of turns.

[0007] The object is achieved by a stator for an electric machine of a traction drive of a motor vehicle with the features of claim 1. The object is further achieved by a use with the features of claim 11 and by a traction drive with the features of claim 12. Preferred embodiments of the invention are described in the subclaims, in the description or the figures, wherein further features described or shown in the subclaims or in the description or the figures can represent an object of the invention individually or in any combination, unless the context clearly indicates the opposite.

[0008] A stator for an electric machine of a traction drive of a motor vehicle is described, wherein the stator comprises an annular stator core with a plurality of slot positions, wherein a plurality of plug-in coils are provided which are arranged in the slot positions passing one another using a hairpin winding technology to form a stator winding, and wherein in each slot position an odd number of layers of the plug-in coils are arranged one above the other in the radial direction of the stator core, wherein the odd number is ≥ 3, and the plug-in coils are formed by standard plug-in coils and one special plug-in coil, wherein an even number of standard plug-in coils are formed with a layer jump between the slot positions receiving the plug-in coils, and a special plug-in coil is formed without a layer jump between the slot positions receiving the plug-in coil.

[0009] Such a stator has significant advantages over state-of-the-art solutions.

[0010] Thus, a stator for an electric machine of a traction drive of a motor vehicle is described. The stator described here is part of a stator-rotor arrangement, which is part of an electric machine or electric motor. In a conventional manner, the rotor is driven by the stator, for example, to drive a shaft or a wheel of a motor vehicle. For this purpose, the stator has a stator winding for interacting with a magnetic or magnetizable element of the rotor and thereby causing the rotor to rotate.

[0011] More specifically, the stator comprises an annular stator core surrounding a particularly cylindrical receiving area for accommodating the rotor. The stator, or rather the stator core, comprises a plurality of slot positions, which define positions within slots for arranging the stator winding. The slot positions can thus also be simply referred to as slots in which the stator winding can be arranged.

[0012] For example, in a rotor that can be described as an internal rotor, the slot positions are preferably arranged axially on an inner surface of the stator core that is oriented inward in the radial direction of the stator core and are spaced apart from one another in the circumferential direction of the stator core. The slot positions can preferably always be spaced the same distance from one another in order to enable a uniform distribution of the slot positions along the inner circumference. This can ensure that the winding arranged in the slot positions can interact evenly with the rotor effectively and independently of the rotation of the rotor, thus driving it. Furthermore, winding elements arranged in the slot positions can face the rotor.

[0013] To form the stator winding, a plurality of plug-in coils are provided, which are arranged in the slot positions, passing one another, using hairpin winding technology. Hairpin technology is generally known to those skilled in the art and, in contrast to conventional coil winding technology, is based on plug-in coils that are inserted into the slot positions of the stator core. Plug-in coils, also known as hairpins, are usually made of flat copper wires bent into a U-shape. The legs of the plug-in coils are located at one axial end of the stator core, also known as the hairpin end, and the region connecting the legs is located on the axial end of the stator core opposite the leg ends, also known as the welding end. To form a winding, the leg ends are twisted and welded in a suitable manner in the circumferential direction of the stator core.

[0014] It is further provided that in each slot position an odd number of layers of the plug-in coils are arranged one above the other in the radial direction of the stator core, wherein the odd number is ≥ 3. In other words, in the slot positions or in the slots of the stator core, at least three plug-in coils are arranged one above the other in the radial direction, wherein more than three plug-in coils can also be present, provided that an odd number of plug-in coils is present. Thus, for example, there can be three, five, seven, nine, eleven or more plug-in coils. However, it can be preferred that the total number of layers of the plug-in coils located in the slot positions is limited to a number of ≤ 13, for example ≤ 11, preferably ≤ 9. For example, the total number of layers of the plug-in coils located in the slot positions in the radial direction can thus be in a range from ≥ 3 to ≤ 13, wherein an odd number is present as described above.In the circumferential direction of the stator core, preferably only one leg of a plug-in coil is located in a slot position or, in other words, the legs of a plug-in coil are always located in different slot positions.

[0015] The plug-in coils are formed by so-called standard plug-in coils and one special plug-in coil, in particular by a plurality of standard plug-in coils and only one special plug-in coil. Standard plug-in coils are understood to mean that these plug-in coils can be identical or at least essentially identical to one another and thus constitute the majority of the plug-in coils. The special plug-in coil is a plug-in coil that is designed and, above all, arranged differently than the standard plug-in coils. Accordingly, the special plug-in coil occupies a special position in the winding.

[0016] With regard to the standard plug-in coils and the special plug-in coil, it is provided more precisely that an even number of standard plug-in coils are designed with a layer jump between the slot positions receiving the plug-in coils, i.e. the respective standard plug-in coil, and at least one special plug-in coil is designed without a layer jump between the slot positions receiving the plug-in coil, i.e. the respective special plug-in coil.

[0017] Accordingly, it may be preferred that a suitable quantity of control plug-in coils is present in an even number and a special plug-in coil is provided in order to achieve the odd number of layers in the slot position.

[0018] The control plug-in coils are designed with a layer jump between the slot positions accommodating the plug-in coils. A layer jump, in the sense of the invention, is understood to mean that the respective radial position or position in the slot or in the slot position changes from one leg of the plug-in coil to the other leg of the plug-in coil. Particularly preferably, a layer jump of 1 can be present, i.e., a change by one radial position. For example, in the radial direction, one leg can be the second position from the radial outside and the other leg can be the third position from the radial outside, based on the intended number of layers or plug-in coils.

[0019] The special plug-in coil is designed to be non-intersecting. Accordingly, both legs of the special plug-in coil are positioned in the same radial position in the slot, or rather, in the slot position.

[0020] A previously described hairpin winding technology or the described winding can provide significant advantages over the state-of-the-art solutions.

[0021] In principle, it is possible to form a particularly variable number of turns without complex guidance of the plug-in coils relative to one another and thus without a complex geometry of the plug-in coils and, furthermore, with welding patterns that are simplified compared to the state of the art.

[0022] The winding topology can thus be significantly simplified compared to the state of the art, allowing even numbers of turns that were previously impossible or very costly to manufacture in the prior art to be easily achieved. This also enables large-scale production of turns that were previously impossible or not economically viable. The variability and adaptability of the winding can thus be significantly improved.

[0023] Furthermore, according to the invention, the cross-sections of the respective plug-in coils can be increased compared to the cross-sections of the prior art, even with previously complex winding counts. This reduces the thermal load on the winding and, accordingly, on the stator. This enables higher performance, which further improves the variability of the electric motor constructed with such a stator. Furthermore, thermal susceptibility can be improved, which can prevent or at least reduce damage and service downtimes caused by thermal influences.

[0024] In principle, the range of applications is very large, so that 400V or even 800V systems can be created, which further improves variability.

[0025] Another advantage is that the plug-in coils only need to be welded on the welding side and not in the winding head. This allows the welding process to be carried out without complex procedures, significantly simplifying production.

[0026] Furthermore, the stator can be designed with a particularly compact installation space, particularly with regard to its axial length. This can be achieved by a winding head with very small axial installation space, which is made possible by the previously described arrangement and design of the plug-in coils. Furthermore, there is no need to leave free axially aligned ends on the winding head, for example, with plug-in coils of different lengths, which serve as welded contacts according to the prior art. This can also reduce the axial length of the stator according to the invention.

[0027] This can also be seen from the fact that the described stator or its stator winding is formed exclusively from plug-in coils, i.e. hairpins, and further coils, such as I-pins, are not present.

[0028] The special plug-in coil can preferably be arranged on a radially inner or a radially outer layer in the slot position. In this embodiment, the formation of the special plug-in coil can be particularly simple, since it can be easily shaped in such a way that it can be guided along the control plug-in coils or other special plug-in coils or can avoid them. This allows the winding topology of the control plug-in coils to be kept simple and without taking the special plug-in coil into account. The formation of the winding and also the implementation of the invention in existing systems can thus be further simplified. A radially outer position is understood to mean the outermost position of the layers of the plug-in coils. Accordingly, a radially inner position is understood to mean the innermost position of the layers of the plug-in coils.

[0029] The radially outermost position of the special plug-in coil is the preferred arrangement for a rotor designed as an internal rotor, since the special plug-in coil in the winding head is usually formed in two layers in the radial direction of the stator and thus exists side by side in the position of two layers. This prevents the winding head of the special plug-in coil from protruding too far in the radial direction, which could hinder the arrangement of the rotor in the stator cavity. Accordingly, it is advantageous that the radially inner position of the special plug-in coil is preferably provided for a rotor designed as an external rotor.

[0030] With regard to the special plug-in coil, it may further be preferred that it has a groove jump which corresponds to the following sequence: [Pole pitch+1−Pole pitch−1], where the pole pitch is defined as follows: Total number of slot positionsTotal number of poles.

[0031] It has surprisingly been shown that, particularly in this configuration, a simple winding topology can be achieved, allowing the construction of a wide variety of winding numbers without any problems. Furthermore, such a slot jump sequence can be achieved with only two types of special plug-in coils, which can further simplify the process.

[0032] In the context of the invention, a slot jump is understood in particular to mean the number of slots or slot positions by which a second leg of a plug-in coil is shifted from a first leg of the plug-in coil. For example, with a slot jump of 6, the second leg is shifted by 6 slots from the first leg. The sequence of the slot jump always refers to adjacent plug-in coils of the same pole.

[0033] For an example number of slots of 48 and a number of poles of 8, a slot jump occurs in the following sequence: -[7 - 5]-, i.e. in a repeating sequence a slot jump of 7 slot positions and a slot jump of 5 slot positions.

[0034] In an alternative embodiment, it can be provided that the special plug-in coil has a groove jump which corresponds to the following sequence: [pole pitch+1−pole pitch−pole pitch−1−pole pitch], where the pole pitch is defined as follows: Total number of slot positionsTotal number of poles.

[0035] This design also enables a particularly simple winding topology, so that the construction of different numbers of turns is possible without any problems.

[0036] For an example number of slots of 48 and a number of poles of 8, a slot jump occurs in the following sequence: -[7 - 6 - 5 - 6]-.

[0037] It may further be preferred for the control plug-in coils to have a uniform slot pitch. In other words, the slot pitch can be identical for all existing control plug-in coils.

[0038] Further preferably, the control plug-in coils can have a layer jump of 1.

[0039] It has been shown that, particularly in combination with the above-described arrangement of the special plug-in coil, such a layer jump and / or slot jump, which preferably applies to all control plug-in coils, can enable a simplified winding topology compared to the prior art, which can allow a particularly simple design of stator coils with a large variability in terms of the number of turns.

[0040] It may further be preferred that the hairpin winding technology produces a number of turns of 10, 14, 15, 18, 20, 21, 27, 28, 36, 40, preferably 20. In particular, such numbers of turns were usually complex and not economically viable to produce in the prior art, so that the advantages of the present invention can be particularly pronounced in this embodiment.

[0041] More preferably, the stator can have at least one of a total number of slot positions of 72, 54, or 48 and a total number of poles of 8 or 6. It has been shown that such configurations find particularly broad application, particularly in the e-mobility sector, and that particularly advantageous variability with regard to the number of turns is also possible with such configurations. The total number of slot positions and the total number of poles can, in principle, be combined as desired, as mentioned above. In one exemplary configuration, the stator can have a total of 48 slot positions and a total number of poles of 8.

[0042] It may further be preferred that the special plug-in coils are formed with a receiving space for the control plug-in coils, so that they can be guided along the control plug-in coils, avoiding them. This embodiment clearly shows that the special plug-in coils are designed to be guided along the control plug-in coils, thus enabling a free design of the control plug-in coils. The invention can therefore be implemented essentially based on the design of the special plug-in coils, demonstrating the simplicity of the structure and the ease of implementation in existing systems.

[0043] For this embodiment, the aforementioned radially inner or outer position, or at the innermost position, i.e. closest to the air gap, or outermost position, i.e. at the groove base, is preferably placed within the groove.

[0044] This position of the special plug-in coil makes it particularly advantageous for the sections of the associated plug-in coils that run in air to be guided past each other without colliding with other plug-in coils, in particular the control plug-in coils.

[0045] For the corresponding design of the receiving space, it can be advantageous for the special plug-in coils to be shaped in such a way that they run out of one plane and extend comparatively strongly inwards or outwards in order to be guided along the standard plug-in coils in the space thus gained.

[0046] In principle, the number of plug-in coils in the slot positions is an odd number, greater than or equal to three. In the area of ​​the winding head, i.e., the area where the leg ends of the special plug-in coil are twisted in the circumferential direction of the stator and / or the area where the two coil legs of a hairpin special plug-in coil are directly connected to each other, the special plug-in coil is designed to be formed in sections in the radial position of different, but preferably adjacent, layers.In other words, the special plug-in coil is deflected in the region of the winding head at least in sections to an avoidance radius which is different from the respective radial position of the special plug-in coil in the slot position, so that the special plug-in coil in the winding head runs in a first radial position in one section and in a second radial position different from the first radial position in another section.

[0047] By designing the winding head of the special plug-in coil at least partially in the radial position of two different layers, this allows for a simple design that reduces the installation space in the axial direction of the stator. Accordingly, it may be characteristic that the special plug-in coil, although it does not exhibit any layer jumps in the slot positions, is guided in sections in the radial position of two different, particularly adjacent, layers in the area of ​​the winding head. This allows adjacent special plug-in coils to be guided preferentially along one another.

[0048] For further technical features or advantages of the stator, reference is made to the description of the use, the traction drive, the figures and the description of the figures.

[0049] Further described is the use of a hairpin winding technology for forming a stator winding for a stator of a traction drive of an electrically driven motor vehicle, wherein the stator comprises an annular stator core with a plurality of slot positions, wherein a plurality of plug-in coils are provided which are arranged in the slot positions passing one another to form the stator winding, and wherein in each slot position an odd number of layers of the plug-in coils are arranged one above the other in the radial direction of the stator core, wherein the odd number is ≥ 3, and the plug-in coils are formed by standard plug-in coils and a special plug-in coil, wherein an even number of standard plug-in coils are formed with a layer jump between the slot positions receiving the plug-in coils, and a special plug-in coil without a layer jump is provided between the slot positions receiving the plug-in coil.

[0050] A previously described hairpin winding technology or the described winding can provide significant advantages over the state-of-the-art solutions.

[0051] In principle, it is possible to create a particularly variable number of turns without complex guidance of the plug-in coils relative to one another and thus without a complex geometry of the plug-in coils, and furthermore with welding patterns that are simplified compared to the prior art. The winding topology can thus be significantly simplified compared to the prior art, so that even numbers of turns that were impossible or very difficult to produce in the prior art can be easily achieved. According to the invention, this also enables large-scale production of turns that were previously impossible or not economically viable. The variability and adaptability of the winding can thus be significantly improved.

[0052] Furthermore, according to the invention, the cross-sections of the respective plug-in coils can be increased compared to the cross-sections of the prior art, even with previously complex winding counts. This reduces the thermal load on the winding and, accordingly, the stator. This enables higher performance, which further improves the variability of the electric motor constructed with such a stator.

[0053] For further technical features or advantages of use, reference is made to the description of the stator, the traction drive, the figures and the description of the figures.

[0054] Also described is a traction drive for an electrically driven motor vehicle, comprising an arrangement of a rotor and a stator, the stator being configured as described above. The traction drive thus comprises, in a manner known per se, an arrangement of a rotor and a stator. The stator is configured as described above and has a stator winding acting on the rotor. The rotor is accordingly arranged in a receiving space of the stator and can be set in rotation by the stator. The rotor can thus drive an axle or a wheel of an electrically driven motor vehicle.

[0055] An electrically powered motor vehicle can be understood as a purely electrically powered motor vehicle or a hybrid vehicle.

[0056] Due to the design of the stator and in particular due to the winding technology used, the aforementioned advantages can be made possible, in particular with regard to improved variability with regard to the number of turns as well as the reduced thermal load.

[0057] For further technical features or advantages of the traction drive, reference is made to the description of the stator, the use of the figures and the description of the figures.

[0058] The invention is further explained below with reference to the figures, where individual or multiple features of the figures may constitute a feature of the invention, either individually or in combination. Furthermore, the figures are to be viewed only as examples and in no way limiting. Fig. 1 shows details of a stator according to an embodiment of the present invention; Fig. 2 shows an embodiment of a special plug-in coil for a stator according to an embodiment of the invention; Fig. 3 shows a further view of a special plug-in coil for a stator according to an embodiment of the invention; Fig. 4 shows the layout of the plug-in coils at one axial end of the stator; and Fig. 5 shows another view of the layout of the plug-in coils at one axial end of the stator.

[0059] In the Fig. 1 shows a detailed view of a stator 10 for an electric machine of a traction drive of a motor vehicle. The stator 10 comprises an annular stator core 12, which has an interior receiving space 14 for accommodating a rotor (not shown) that can generally be configured in a conventional manner. The stator core 12 comprises a plurality of slot positions 16 on its inner circumference 18, which, when the rotor is arranged in the receiving space 14, thus point toward the rotor. The slot positions 16 run parallel in the axial direction and are preferably distributed evenly or at equal intervals.

[0060] In the slot positions 16, a plurality of plug-in coils 20 are arranged, which are formed by control plug-in coils 20a and at least one special plug-in coil 20b. In the Fig. 1, only the special plug-in coils 20b are shown, with the positions of the control plug-in coils 20a merely indicated. Basically, the plug-in coils 20 are arranged in the slot positions 16, passing one another, using hairpin winding technology to form a stator winding 22.

[0061] In the Fig. 1 it can also be seen that in each slot position 16 an odd number of layers of plug-in coils 20 are arranged one above the other in the radial direction of the stator core 12. In detail, Fig. 1 four control plug-in coils 20a are formed with a layer jump between the slot positions 16 receiving the control plug-in coils 20a and furthermore a special plug-in coil 20b is formed without a layer jump between the slot positions 16 receiving the special plug-in coil 20b. With regard to the layer jump, reference is made to the Fig. 4.

[0062] The special plug-in coil 20b is further arranged on the radially outermost layer in slot position 16, thus being the radially outermost layer of the plug-in coils 20. The configuration of the special plug-in coil 20b on the radially outer layer in slot position 16 is particularly advantageous if, as shown, the stator 10 is designed for an internal rotor (not shown), since this prevents the special plug-in coil 20b from being deflected too far inward in the radial direction of the stator 10 in the region of the winding head 30, which could otherwise complicate the arrangement of the rotor in the cavity of the stator 10.

[0063] In the Fig. 2 and Fig. 3 shows corresponding special plug-in coils 20b in detail. These are shaped in such a way that they have a receiving space 24 for the control plug-in coils 20a or, if applicable, the special plug-in coils 20b. The goal is for the special plug-in coils 20b to be guided along the control plug-in coils 20a, thereby avoiding the control plug-in coils 20a. This makes it possible for the control plug-in coils 20a to be shaped and arranged in a conventional manner and for the special plug-in coils 20b to be arranged running along them at a radially inner or outer position.

[0064] In the Fig. 2 and Fig. 3 shows that the special plug-in coils 20b are basically shaped like so-called hairpins known to those skilled in the art. However, the special plug-in coils 20b have a strong outward bend at defined positions in order to assume a shape, also referred to as an escape radius, exclusively in the area of ​​the winding head 30 and to form the receiving space 24 for the control plug-in coils 20b. The positions at which a comparatively strong bend is present are shown by the escape points 26. Furthermore, welding points 28 are shown, at which adjacent special plug-in coils 20b can be welded together. It should be noted that the terms escape points 26 and welding points 28 are intended to indicate the corresponding positions, but should not be understood as limiting them to merely points. Of course, corresponding extended areas can also be present.

[0065] In the Fig. 3 also shows a plurality of welded special plug-in coils 20b. The welding points 28 and the deflection points 26 are also shown. Fig. 3 also shows the receiving areas 24 in which the control plug-in coils 20a can be accommodated.

[0066] It is thus clear that the special plug-in coil 20b is guided in the region of the winding head 30 of the stator 10 in sections in the radial position of different, in particular adjacent, layers.

[0067] In the Fig. 4 shows the winding head 30 of the stator 10. The deflection point 26 is shown as an example of a special plug-in coil 20b, at which the special plug-in coil 20b is formed such that the special plug-in coil 20b, although guided without layer jumps, leaves a layer in sections in the region of the winding head 30 and continues in an adjacent layer, thus forming the receiving area 24.

[0068] The same is also true in the Fig. 5, which also shows the winding head 30. The lower four layers are formed by the standard plug-in coils 20a, and the upper two layers are formed by the special plug-in coils 20b. Accordingly, the geometry described above guides the special plug-in coils 20b in two adjacent layers. List of reference symbols 10 Stator 12 Stator core 14 Recording room 16 Groove position 18 inner circumference 20 plug-in coil 20a control plug-in coil 20b special plug-in coil 22 Stator winding 24 recording room 26 Alternative point 28 welding points 30 winding head QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2022 120 729 A1

[0004]

Claims

[1] Stator (10) for an electric machine of a traction drive of a motor vehicle, wherein the stator (10) comprises an annular stator core (12) having a plurality of slot positions (16), wherein a plurality of plug-in coils (20) are provided, which are arranged in the slot positions (16) passing one another in a hairpin winding technology to form a stator winding (22), and wherein in each slot position (16), an odd number of layers of the plug-in coils (20) are arranged one above the other in the radial direction of the stator core (12), wherein the odd number is ≥ 3, and the plug-in coils (20) are formed by control plug-in coils (20a) and a special plug-in coil (20b), wherein an even number of control plug-in coils (20a) is formed with a layer jump between the slot positions (16) receiving the plug-in coils (20), and a special plug-in coil (20b) is formed without a layer jump between the groove positions (16) receiving the plug-in coil (20). [2] Stator (10) according to claim 1, characterized by that the special plug-in coil (20b) is arranged on a radially inner or a radially outer position in the groove position (16). [3] Stator (10) according to claim 1 or 2, characterized by that the special plug-in coil (20b) has a groove jump which corresponds to the following sequence: [Pole pitch+1−Pole pitch−1], where the pole pitch is defined as follows: Total number of slot positionsTotal number of poles. [4] Stator according to claim 1 or 2, characterized by that the special plug-in coil has a groove jump which corresponds to the following sequence: [pole pitch+1−pole pitch−pole pitch−1−pole pitch], where the pole pitch is defined as follows: Total number of slot positionsTotal number of poles. [5] Stator (10) according to one of claims 1 to 4, characterized by that the control plug-in coils (20a) have a position jump of 1. [6] Stator (10) according to one of claims 1 to 5, characterized by that the hairpin winding technology produces a number of turns of 10, 14, 15, 18, 20, 21, 27, 28, 36, 40, preferably 20. [7] Stator (10) according to one of claims 1 to 6, characterized by that the stator (10) has at least one of a total number of slot positions (16) of 72, 54 or 48 and a total number of poles of 8 or 6. [8] Stator (10) according to one of claims 1 to 7, characterized by that the special plug-in coils (20b) are formed with a receiving space (24) for the control plug-in coils (20a) in order to be guided along the control plug-in coils (20a) in an evasive manner. [9] Stator (10) according to one of claims 1 to 8, characterized bythat the special plug-in coil (20b) is guided in the region of the winding head (30) of the stator (10) in sections in the radial position of different, in particular adjacent, layers. [10] Stator (10) according to one of claims 1 to 9, characterized by that the total number of layers of the plug-in coils (20) located in the slot positions is limited to a number of ≤ 13. [11] Use of a hairpin winding technology for forming a stator winding (22) for a stator (10) of a traction drive of an electrically driven motor vehicle, characterized bythat the stator (10) comprises an annular stator core (12) with a plurality of slot positions (16), wherein a plurality of plug-in coils (20) are provided, which are arranged in the slot positions (16) passing one another to form the stator winding (22), and wherein in each slot position (16) an odd number of layers of the plug-in coils (20) are arranged one above the other in the radial direction of the stator core (12), wherein the odd number is ≥ 3, and the plug-in coils (20) are formed by standard plug-in coils (20a) and a special plug-in coil (20b), wherein an even number of standard plug-in coils (20a) is formed with a layer jump between the slot positions (16) receiving the plug-in coils (20), and a special plug-in coil (20b) without a layer jump between the slot positions receiving the plug-in coil (20) (16). [12] Traction drive for an electrically driven motor vehicle, comprising an arrangement of a rotor and a stator (10), characterized by that the stator (11) is designed according to one of claims 1 to 11.

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