Plug-in coil for a winding arrangement of a stator and stator with a winding arrangement

Abstract

Plug-in coil 100 for a winding arrangement 1 of a stator 0 comprising a first leg section 10, a second leg section 20 arranged offset from the first leg section 10, and a head section 30 which electrically connects an upper end section 10a of the first leg section 10 to an upper end section 20a of the second leg section 20, wherein the head section 30 comprises a first curved leg 31 which is electrically connected and spaced from the end section 10a of the first leg section 10 via a first bridge section 33, and a second curved leg 32 arranged on the first curved leg 31, which is electrically connected and spaced from the end section 20a of the second leg section 20 via a second bridge section 34,and wherein an arc plane BE spanned by the first arc leg 31 and the second arc leg 32 is offset from a base plane GE spanned by the first leg section 10 and the second leg section 20 and encloses an obtuse angle δ in a range between 90° and 180°, preferably between 135° and 180°.

Description

[0001] The invention relates to a plug-in coil for a winding arrangement of a stator and a stator with a winding arrangement.

[0002] The invention lies in the technical field of coils for winding arrangements for electric motors of electric vehicles, in particular electrically powered cars and electrically powered trucks, and winding arrangements for electric motors of electric vehicles, in particular electrically powered cars and electrically powered trucks.

[0003] Electric motors consist of conductor strands wound into coils on the teeth of the electric motor's stator. During operation, the current-carrying coils generate a rotating magnetic field that drives the electric motor's rotor. The way the conductor strands are wound, as well as their shape and properties, define the winding arrangement for the electric motor's stator. In distributed winding arrangements, the conductor strands are not wound around one tooth each to form a coil, but rather have slot pitches greater than one, meaning the conductor strands are each wound around several teeth to form a coil.

[0004] It is well known that flat wire conductors are used for conductor strands to achieve a particularly high fill factor, as their rectangular cross-section allows the stator slots to be filled as tightly as possible. A special form of this is flat wire designed as a plug-in coil. To form a plug-in coil, a flat wire is usually bent into a so-called hairpin geometry, i.e., a U-shaped geometry reminiscent of a hairpin. Such plug-in coils are called hairpin plug-in coils.

[0005] Fig. 1a and Fig. 1b schematically show such a hairpin plug-in coil 101 in front and side views, respectively. This hairpin plug-in coil 101 is made from a single bent flat wire and comprises a first leg section 10, a second leg section 20 arranged offset from the first leg section 10, and a hairpin head section 102 that electrically connects an upper end section 10a of the first leg section 10 to an upper end section 20a of the second leg section 20. The hairpin head section 102 comprises a first curved leg 31 and a second curved leg 32 arranged thereon, each of which tapers to a point and roof-like shape as a direct extension of the first leg section 10 and the second leg section 20, respectively. The arch plane BE spanned by the first arch leg 31 and the second arch leg 32 is not offset from the base plane GE spanned by the first leg section 10 and the second leg section 20, but merges directly into it.

[0006] The leg sections of the plug-in coil are arranged within the slots on conductor tracks running concentrically around the stator's rotational axis to form the turns of the coils of the winding arrangement. The head section of the plug-in coil is arranged outside the slots, with the entire head sections of the plug-in coils together forming the winding head protruding from the stator.

[0007] This winding head should be as small and space-saving as possible. In particular, the winding head should protrude as little as possible, or not at all, into the stator's rotor mounting space to ensure plenty of space for installation and operation of the rotor. This therefore places special demands on the head section of the plug-in coil.

[0008] Since in known hairpin plug-in coils, the first curved leg and the second curved leg of the head section are arranged in such a way as to taper to a point and roof-like shape as an extension of the first leg section and the second leg section, the arrangement of several such plug-in coils in a winding arrangement results in adjacent head sections fanning out significantly. This disadvantageously increases the space required for the winding head. This is particularly disadvantageous when these known hairpin plug-in coils are located on the innermost conductor layer, which is closest to the stator's rotational axis, and the winding head thus formed protrudes toward the stator's receiving space for the rotor.

[0009] It is the object of the present invention to overcome the disadvantages of the prior art and in particular to provide a plug-in coil for a winding arrangement of a stator which allows space-saving winding arrangements, and further in particular to provide a stator with a winding arrangement which is particularly space-saving.

[0010] This object is achieved by a plug-in coil for a winding arrangement of a stator and a stator with a winding arrangement according to the respective independent claim. Advantageous aspects of the invention form the subject matter of the respective dependent claims.

[0011] The invention comprises a plug-in coil for a winding arrangement of a stator comprising a first leg section, a second leg section arranged offset from the first leg section, and a head section which electrically connects an upper end section of the first leg section to an upper end section of the second leg section, wherein the head section comprises a first curved leg which is electrically connected and spaced apart from the end section of the first leg section via a first bridge section, and a second curved leg arranged on the first curved leg which is electrically connected and spaced apart from the end section of the second leg section via a second bridge section,and wherein an arc plane spanned by the first arch leg and the second arch leg is offset from a base plane spanned by the first leg section and the second leg section and encloses an obtuse angle δ in a range between 90° and 180°, preferably between 135° and 180°.

[0012] By keeping δ in a range between 90° and 180°, preferably between 135° and 180°, and offsetting the arc plane from the base plane, the plug-in coil can be arranged in the stator's winding arrangement so that the head section protrudes from the stator slots to save space. Furthermore, if several plug-in coils are arranged next to each other, their head sections fan out less.

[0013] The first bridge section and the second bridge section can be designed in such a way as to space the first curved leg from the end section of the first leg section and the second curved leg from the end section of the second leg section, respectively, such that when the plug-in coil is arranged in a winding arrangement of a stator, the first curved leg and the second curved leg are arranged further from the rotational axis of the stator than the first leg section and the second leg section, respectively. The first bridge section and the second bridge section can run at least partially (parallel) along a radial direction of the stator. This can prevent the first curved leg and the second curved leg from protruding into the receiving space of the stator for the rotor.

[0014] According to an advantageous aspect, the arc plane is offset substantially parallel to the base plane. This can be achieved by setting δ = 180° ± 5°, preferably δ = 180° ± 2°.

[0015] According to a further advantageous aspect, the first bridge section and the second bridge section are each designed to space the first arch leg from the upper end section of the first leg section and the second arch leg from the upper end section of the second leg section by a transverse distance, wherein the transverse distance corresponds to at least four times, preferably at least eight times, a cross-sectional width of the first leg section.

[0016] If the plug-in coil is arranged in a winding arrangement of a stator with multiple conductor track layers, in which adjacent conductor track layers are spaced apart from each other in the radial direction of the stator essentially by a cross-sectional width, the first bridge section and the second bridge section can space the first arc leg and the second arc leg, respectively, in the radial direction of the stator. The transverse spacing can be selected according to the number of conductor track layers.

[0017] According to a preferred aspect, a first circular arc section is arranged at the upper end section of the first leg section, which has a first central angle β1 in a range between 45° ≤ β1 ≤ 180°, preferably between 90° ≤ β1 ≤ 180°, particularly preferably between 120° ≤ β1 ≤ 180°. Additionally or alternatively, a second circular arc section is arranged at the upper end section of the second leg section, which has a second central angle β2 in a range between 45° ≤ β2 ≤ 180°, preferably between 90° ≤ β2 ≤ 180°, particularly preferably between 120° ≤ β2 ≤ 180°.

[0018] According to a further preferred aspect, a first chord spacing of the first circular arc section corresponds to a maximum of four times, preferably a maximum of twice, particularly preferably a maximum of once, the cross-sectional width of the first leg section. Additionally or alternatively, a second chord spacing of the second circular arc section corresponds to a maximum of four times, preferably a maximum of twice, particularly preferably a maximum of once, the cross-sectional width of the first leg section.

[0019] If the plug-in coil is used in a winding arrangement of a stator, the first circular arc section can space the first bridge section from the upper end section of the first leg section in an azimuthal direction of the stator. The second circular arc section can then space the second bridge section from the upper end section of the second leg section in the azimuthal direction of the stator. The first bridge section and the second bridge section can then run offset from a groove, for example, along a tooth of the stator.

[0020] According to a particularly preferred aspect, the first leg section has, at a lower end section, a lower crimp section facing the second leg section. Additionally or alternatively, the second leg section has, at a lower end section, a lower crimp section facing or remote from the first leg section. The lower crimp sections can be configured such that, when the plug-in coil is arranged in a winding arrangement of a stator, they extend at least partially along an azimuthal direction of the stator.

[0021] The invention further comprises a stator with a winding arrangement, wherein the winding arrangement comprises at least one plug-in coil according to one of the preceding claims. In such a stator with such a winding arrangement, the winding head can be easily configured such that it does not protrude into the stator's receiving space for the rotor.

[0022] According to an advantageous aspect, the first leg section and the second leg section of the at least one plug-in coil are arranged within slots of the stator and on a radially innermost conductor track layer with respect to a rotational axis of the stator. The arrangement of the at least one plug-in coil on the radially innermost conductor track layer is particularly advantageous to prevent the winding head from protruding into the stator's receiving space for the rotor.

[0023] Plug-in coils in which the first leg section and the second leg section are both arranged on the same conductor track layer can function as so-called backtwist pins in (distributed) winding arrangements. While in the prior art the first leg section and the second leg section of such plug-in coils are arranged on the radially outermost conductor track layer with respect to the rotation axis of the stator, the described advantageous aspect of the invention provides for laying them on the innermost conductor track layer. In particular, this allows power connection pins, which would otherwise be arranged on the innermost conductor track layer, to be arranged on the outermost conductor track layer. This allows a connection lead (orConnection) to the power connection pins can advantageously be made directly radially on the outer diameter (i.e. facing the outermost conductor layer in the radial direction) and does not have to be guided over the head sections of the plug-in coils that protrude from the stator and form the winding head, which leaves more installation space free in the axial direction of the stator.

[0024] According to a further advantageous aspect, the winding arrangement comprises at least one hairpin plug-in coil which at least partially encompasses the first bridge section and / or second bridge section of the at least one plug-in coil.

[0025] According to a particularly advantageous aspect, the first bridge section and the second bridge section of the at least one plug-in coil are each designed in such a way as to be arranged to run from the radially innermost conductor track layer with respect to the rotational axis of the stator to the radially outermost conductor track layer with respect to the rotational axis of the stator.

[0026] The figures show: Fig. 1a Schematic front view of a hairpin plug-in coil from the prior art; Fig. 1b Schematic side view of the hairpin plug-in coil from Fig. 1a; Fig. 2a Schematic perspective view of a plug-in coil in a preferred embodiment; Fig. 2b Schematic side view of the plug-in coil from Fig. 2a; Fig. 3a Schematic perspective view of a plug-in coil in a particularly preferred embodiment; Fig. 3b Schematic detailed view of the circular arc section of the plug-in coil from Fig. 3a; Fig. 4a Schematic side view of a stator with a winding arrangement in a preferred embodiment; Fig. 4b Schematic top view of the stator with a winding arrangement of Fig. 4a; Fig. 4c Schematic detailed view from inside to outside of a part of the winding arrangement from Fig. 4a; and Fig. 4d Schematic detail view from outside to inside of a part of the winding arrangement from Fig. 4a.

[0027] In the following, the invention is explained in more detail with reference to embodiments shown in the figures.

[0028] Fig. 2a shows a schematic perspective view of a plug-in coil 100 in a preferred embodiment and Fig. 2b a schematic side view of the plug-in coil 100 from Fig. 2a.

[0029] The plug-in coil 100 shown is made from a single bent flat wire and includes a first leg portion 10, a second leg portion 20 offset from the first leg portion 10, and a head portion 30 electrically connecting an upper end portion 10a of the first leg portion 10 to an upper end portion 20a of the second leg portion 20.

[0030] The head section 30 comprises a first curved leg 31, which is electrically connected and spaced from the end section 10a of the first leg section 10 via a first bridge section 33, and a second curved leg 32 arranged on the first curved leg 31, which is electrically connected and spaced from the end section 20a of the second leg section 20 via a second bridge section 34.

[0031] The first arch leg 31 and the second arch leg 32 taper to a point (in the illustration shown upwards). An arch plane BE spanned by the first arch leg 31 and the second arch leg 32 is offset from a base plane GE spanned by the first leg section 10 and the second leg section 20. The arch plane BE is parallel to the base plane GE, so that the arch plane BE forms an angle δ = 180° with the base plane GE.

[0032] The first bridge section 33 and the second bridge section 34 are each designed to space the first arch leg 31 from the upper end section 10a of the first leg section 10 and the second arch leg 32 from the upper end section 20a of the second leg section 20 by a transverse distance Q which, in the example shown, corresponds to eight times the cross-sectional width B of the first leg section 10.

[0033] Fig. 3a shows a schematic perspective view of a plug-in coil 100 in a particularly preferred embodiment and Fig. 3b a schematic detailed view of a circular arc section 40, 50 of the plug-in coil 100 from Fig. 3a. This embodiment has all the features of the Fig. 2a and Fig. 2b, the description of which therefore also applies to the embodiment shown in Fig. 3a shown embodiment can be used. In Fig. 3a is also a rectangular

[0034] Coordinate system along the shown width direction B, depth direction T and height direction H. As a further development of the Fig. 2a and Fig. 2b, this embodiment has the following features.

[0035] A first circular arc section 40 is arranged at the upper end section 10a of the first leg section 10, and a second circular arc section 50 is arranged at the upper end section 20a of the second leg section 20. The first circular arc section 40 has a first center angle β1 = 170°, and the second circular arc section 50 has a second center angle β2 = 170°. The first chord spacing KS1 of the first circular arc section 40 and the second chord spacing KS2 of the second circular arc section 50 each correspond to twice the cross-sectional width B of the first leg section 10.

[0036] The first leg section 10 also has, at a lower end section 10b, a lower crimp section 12 facing the second leg section 20, and the second leg section 20 has, at a lower end section 20b, a lower crimp section 22 facing away from the first leg section 10, both of which extend substantially in a plane spanned by the width direction B and the height direction H.

[0037] The advantages of such a plug-in coil 100 are also particularly evident when arranged in a winding arrangement 1 ( Fig. 4a - 4d) of a stator 0 ( Fig. 4a - 4d), as in the Fig. 4a - 4d, and are related to the Fig. 4a - 4d further described.

[0038] Fig. 4a - 4d show various schematic views of a stator 0 with a winding arrangement 1 in a preferred embodiment. Fig. 4a a schematic side view, Fig. 4b a schematic plan view, Fig. 4c a schematic detailed view from the inside to the outside of a part of the winding arrangement 1, and Fig. 4d a schematic detailed view from outside to inside of a part of the winding arrangement 1.

[0039] The winding arrangement 1 comprises nine plug-in coils 100 arranged next to one another of the embodiment as shown in Fig. 3a. The reference numerals of a plug-in coil 100 are shown in the Fig. 4b - 4d are shown as an example of the plug-in coil 100 arranged on the outside in the azimuthal direction AR. The winding arrangement 1 further comprises a plurality of hairpin plug-in coils 101 as in Fig. 1a and Fig. 1b shown.

[0040] Both the first leg section 10 ( Fig. 3a) and the second leg section 20 ( Fig. 3a) each plug-in coil 100 are within slots of the stator 0 and on the radially innermost conductor track layer L with respect to the rotation axis R of the stator 0 iTherefore, no layer jump occurs within a plug-in coil 100.

[0041] The first bridge section 33 and the second bridge section 34 of each plug-in coil 100 are each designed in such a way that from the radially innermost conductor track layer L with respect to the rotational axis R of the stator 0 i up to the radially outermost conductor track layer L with respect to the rotation axis R of the stator 0 a to be arranged in a continuous manner.

[0042] The first circular arc section 40 of each plug-in coil 100 spaced the first bridge section 33 from the upper end section 10a of the first leg section 10 by the first chord distance KS1 ( Fig. 3b) in the azimuthal direction AR of the stator 0. Likewise, the second circular arc section 50 of each plug-in coil 100 spaced the second bridge section 34 from the upper end section 20a of the second leg section 20 by the second chord distance KS2 ( Fig.3b) in the azimuthal direction AR of the stator 0. Therefore, the first bridge section 33 and the second bridge section 34 are each offset in the azimuthal direction AR from a groove and run in the radial direction RR along a tooth of the stator 0, each under a hairpin head section 102 and encompassed by a hairpin head section 102 from the innermost conductor layer L i to the outermost conductor layer L a .

[0043] The resulting laying of the first curved leg 31 and the second curved leg 32 of the plug-in coils 100 to the outermost conductor track layer L a prevents the head sections 30 of the plug-in coils 100 from fanning out in the direction of the rotation axis R of the stator 0. As a result, the head sections 30 of the plug-in coils 100 do not protrude into the receiving space of the stator 0 for the rotor. Reference symbol 0 Stator 1 Winding arrangement 10 first leg section 10a upper end section of the first leg section 10b lower end section of the first leg section 12 lower crop section of the first leg section 20 second leg section 20a upper end section of the second leg section 20b lower end section of the second leg section 22 lower crop section of the second leg section 30 head section 31 first bow leg 32 second bow leg 33 first bridge section 34 second bridge section 40 first circular arc section 50 second circular arc section 100 plug-in coils 101 Hairpin plug-in coil 102 Hairpin head section AR Azimuthal direction B Cross-sectional width BE arc level GE Basic Level KS1 first chord distance KS2 second chord distance L aoutermost conductor layer L i innermost conductor layer Q Transverse distance R rotation axis RR radial direction

Claims

[1] Plug-in coil (100) for a winding arrangement (1) of a stator (0), comprising a first leg section (10), a second leg section (20) arranged offset from the first leg section (10), and a head section (30) which electrically connects an upper end section (10a) of the first leg section (10) to an upper end section (20a) of the second leg section (20), wherein the head section (30) comprises a first curved leg (31) which is electrically connected and spaced apart from the end section (10a) of the first leg section (10) via a first bridge section (33), and a second curved leg (32) arranged on the first curved leg (31) which is electrically connected and spaced apart from the end section (20a) of the second leg section (20) via a second bridge section (34).and wherein an arc plane (BE) spanned by the first arc leg (31) and the second arc leg (32) is offset from a base plane (GE) spanned by the first leg section (10) and the second leg section (20) and encloses an obtuse angle δ in a range between 90° and 180°, preferably between 135° and 180°. [2] Plug-in coil (100) according to claim 1, wherein the arc plane (BE) is offset substantially parallel to the base plane (GE). [3] Plug-in coil (100) according to one of the preceding claims, wherein the first bridge section (33) and the second bridge section (34) are each designed to space the first curved leg (31) from the upper end section (10a) of the first leg section (10) and the second curved leg (32) from the upper end section (20a) of the second leg section (20) by a transverse distance (Q), wherein the transverse distance (Q) corresponds to at least four times, preferably at least eight times, a cross-sectional width (B) of the first leg section (10). [4] Plug-in coil (100) according to one of the preceding claims, wherein a first circular arc section (40) is arranged at the upper end section (10a) of the first leg section (10), which has a first central angle β1 in a range between 45° ≤ β1 ≤ 180°, preferably between 90° ≤ β2 ≤ 180°, particularly preferably between 120° ≤ β1 ≤ 180°, and / or wherein a second circular arc section (50) is arranged at the upper end section (20a) of the second leg section (20), which has a second central angle β2 in a range between 45° ≤ β2 ≤ 180°, preferably between 90° ≤ β2 ≤ 180°, particularly preferably between 120° ≤ β2 ≤ 180°. [5] Plug-in coil (100) according to claim 4, wherein a first chord spacing (KS1) of the first circular arc section (40) corresponds to a maximum of four times, preferably a maximum of twice, particularly preferably a maximum of once, a cross-sectional width (B) of the first leg section (10), and / or a second chord spacing (KS2) of the second circular arc section (50) corresponds to a maximum of four times, preferably a maximum of twice, particularly preferably a maximum of once, a cross-sectional width (B) of the first leg section (10). [6] Plug-in coil (100) according to one of the preceding claims, wherein the first leg section (10) has, at a lower end section (10b), a lower crimp section (12) facing the second leg section (20) and / or wherein the second leg section (20) has, at a lower end section (20b), a lower crimp section (22) facing or facing away from the first leg section (10). [7] Stator (0) with a winding arrangement (1), wherein the winding arrangement (1) comprises at least one plug-in coil (100) according to one of the preceding claims. [8] Stator (0) according to claim 7, wherein the first leg portion (10) and the second leg portion (20) of the at least one plug-in coil (100) according to one of the preceding claims are arranged within slots of the stator (0) and on a conductor track layer (L i ) are arranged. [9] Stator (0) according to claim 7 or 8, wherein the winding arrangement (1) comprises at least one hairpin plug-in coil (101) which at least partially encompasses the first bridge section (33) and / or second bridge section (34) of the at least one plug-in coil (100) according to one of the preceding claims. [10] Stator (0) according to claim 8 or 9, wherein the first bridge section (33) and the second bridge section (34) of the at least one plug-in coil (100) according to one of the preceding claims are each designed in such a way as to extend from the radially innermost conductor track layer (L i ) to the radially outermost conductor track layer (L a ) to be arranged in a continuous manner.

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