EP4226480A1

EP4226480A1 - Stator for a rotary electric machine, method for producing the stator, and rotary electric machine

Info

Publication number: EP4226480A1
Application number: EP21790363.2A
Authority: EP
Inventors: Holger Witt
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2020-10-07
Filing date: 2021-09-28
Publication date: 2023-08-16
Also published as: WO2022073544A1; US20230378837A1; DE102021124994A1; CN116325453A

Abstract

The invention relates to a stator for a rotary electric machine, a method for producing the stator, and the rotary electric machine itself. The stator (10) comprises: a stator body (11), which has a plurality of stator teeth (12) arranged in a circumferential direction (14); grooves (15) formed between the stator teeth (12); and conductor sections, arranged in the grooves (15), of at least one conductor pair (30) which forms at least a portion of windings (20) of the stator (10), wherein, in each groove (15), conductor sections of the conductor pair (30) are arranged along the depth (16) of the groove (15) so as to be parallel to and offset from one another and the sequence of the arrangement of the parallel conductor sections in each groove (15), through which the conductors run, alternates in the circumferential direction (14), and wherein the conductors of the conductor pair (30), deviating from a winding direction (21) extending basically in the circumferential direction, meander in a radial direction in a direction extending substantially perpendicular to the circumferential direction (14) and, by means of an enlacement formed thereby in each case, enlace around one group (13) of stator teeth (12). The stator according to the invention, the method for the production thereof, and the rotary electric machine equipped therewith enable a high power density and a high degree of efficiency to be combined with low installation space requirements for the winding heads.

Description

Stator for a rotary electric machine, method of manufacturing the stator and rotary electric machine

The invention relates to a stator for an electrical rotary machine, in particular for an axial flux machine, a method for producing the stator and the electrical rotary machine itself.

The electric drive train of motor vehicles is known from the prior art. This consists of components for energy storage, energy conversion and energy transmission. Energy conversion components include radial flux machines and axial flux machines.

However, radial flux machines often only have one operating point at which they have the best efficiency. Accordingly, they are not designed to adjust the operating point as a function of the changing requirements placed on them and thus to achieve the highest efficiency in accordance with the different requirements of the different operating parameters or at different operating points.

In order to overcome this disadvantage, electric rotary machines that are adapted to the requirements that arise in terms of their operating range are often used, or the disadvantage mentioned is compensated for by coupling the electric rotary machine to a gear unit or by integrating a gear unit into the electric rotary machine, such as with an electric axis.

Various designs with one or more stators and one or more rotors are known from the prior art.

An electric axial flux machine is a motor or generator in which the magnetic flux between a rotor and a stator is realized parallel to the axis of rotation of the rotor.

Such an axial flow machine can be designed in designs that differ in terms of the arrangement of the rotor and/or stator, and different ones Realize special features and advantages in the application, for example as a traction machine for a vehicle.

Axial flux machines exist with different winding forms. A common form of winding is the single-tooth winding. Although single-tooth windings form small winding overhangs, they generate a magnetic field with a high proportion of harmonics, i.e. waves with a different frequency than the number of revolutions of the rotor of the axial flux machine, which negatively influence the acoustics and the efficiency. Axial flux machines with distributed windings have the advantage that the aforementioned disadvantages do not occur, or only to a reduced extent. However, the end windings of these distributed windings require a large amount of space in the axial and/or radial direction.

Large winding overhangs are not desirable, especially in axial flow machines, since they limit the maximum diameter of the active components in the event of radial expansion, which reduces the maximum torque that can be made available. A relatively large axial extension of the end windings results in a larger axial length of the entire rotary electric machine, which is also undesired.

In order to explain the state of the art, specific embodiments are discussed below.

US Pat. No. 6,348,751 B1 discloses an electric motor with active hysteresis control of winding currents and/or with an efficient stator winding arrangement and/or an adjustable air gap to form an axial flux machine. A stator of this electric motor comprises a plurality of segments in a plurality of stator teeth, which are entwined in a serpentine manner with corresponding segments of windings, which are implemented in a plurality of levels. Each phase occupies a respective peripheral area of the stator.

US 2003/0189388 A1 discloses an assembly that has an axial flow machine that includes a stator and a rotor. The stator has a plurality of axially aligned stator teeth which are separated from one another by slots. Windings of a stator winding run around the stator teeth. It can be seen that the end windings have a relatively large volume requirement in the axial and/or radial direction.

US 2019/0252930 A1 relates to a stator arrangement for an axial flux machine and an axial flux machine with such a stator arrangement. The stator assembly comprises a stator having a plurality of stator teeth which are distributed concentrically in the circumferential direction and are arranged separated in the axial direction from a rotor by an air gap, the stator teeth comprising two end sections opposite in the axial direction and a tooth core between the end sections, and each tooth core having a Has core cross-sectional area and is wrapped with at least one coil winding. Corresponding single-tooth windings are provided here.

Proceeding from this, the present invention is based on the object of providing a stator for an electric rotary machine, a method for its production and the electric rotary machine itself equipped with it, which make it possible to achieve high power density and high efficiency with a small space requirement for the to combine winding heads.

This object is achieved by the stator of a rotary electric machine according to claim 1 , by the method for manufacturing a stator of a rotary electric machine according to claim 9 and by the rotary electric machine according to claim 10 .

Advantageous embodiments of the stator according to the invention are specified in subclaims 2-8.

The features of the claims can be combined in any technically meaningful way, with the explanations from the following description and features from the figures also being able to be used for this purpose, which include supplementary configurations of the invention.

The invention relates to a stator of an electrical rotary machine, comprising a stator body that has a plurality of stators arranged along a circumferential direction Having stator teeth and grooves formed between the stator teeth. Conductor sections of at least one conductor pair are arranged in the slots, which forms at least a portion of the windings of the stator, with conductor sections of the conductor pair being arranged in a respective slot offset parallel to one another along the depth of the slot and the order in which the parallel conductor sections are arranged in each slot , through which the conductors pass, alternates along the circumferential direction. Deviating from a winding direction generally running in the circumferential direction, the conductors of the pair of conductors meander in a direction running essentially perpendicularly to the circumferential direction in the radial direction, each winding around a group of stator teeth with a respective looping formed thereby.

In particular, the electrical rotary machine is designed as an axial flux machine.

The vertical direction can also be understood to mean a direction of 60°-120° in relation to an ideal tangent to the circumferential direction. In addition, the course in this direction can also be curved or designed with at least one slight kink.

The stator body can also be referred to as the stator yoke, on which a number of axially protruding stator teeth are arranged. Such a stator support can be formed from the same laminated core as the stator teeth, or alternatively it can also be a plastic support on which the stator teeth are arranged.

The two conductors of a conductor pair that are connected to a respective phase are set up to be polarized differently, starting from a common connection area. Starting from the common connection area, one of the conductors of the pair of conductors can be designated as the positive conductor and the respective other conductor of the pair of conductors as the negative conductor along the general winding direction.

This means that the conductors of a conductor pair that are connected to a respective phase together form a so-called double layer. Along the circumferential direction of the stator, in each slot through which the two conductors pass, the order of arrangement changes along the depth of the slot. A respective The pair of conductors follows in a winding direction that basically runs in the circumferential direction along several stator tooth groups.

The depth of the slot is to be measured from the free end of the stator tooth to the bottom of the slot in the area where the stator tooth is fastened to a load-bearing element or in the area where the stator tooth transitions into a load-bearing area. In the case of an axial flow machine in an I arrangement, the depth of the groove must be determined accordingly in the axial direction.

In an axial flux machine, this means that the conductors meander in the radial direction or also run in serpentines, and that in a first groove the first conductor is arranged axially furthest out on the stator tooth and the second conductor is arranged axially further inwards. At the next slot traversed by the two conductors, the second conductor is located axially outermost on the stator tooth and the first conductor is located axially further inward.

The fact that the conductors of a respective loop thus formed loop around a group of stator teeth means that a loop encompasses a plurality of stator teeth, with the conductors forming the respective loop not passing through grooves located between the looped or encompassed stator teeth.

Due to the parallel arrangement of the conductor sections in the slots, these are arranged in different positions or planes when the electrical rotary machine is designed as an axial flux machine. Due to the alternating sequence, this arrangement of the conductor sections changes from layer to layer for each slot. For example, a first conductor section can be arranged in a first slot in a first layer and a second conductor section can be arranged in this first slot in a second layer, and in a circumferentially closest slot in which the pair of conductors runs, the first conductor section can be in of the second layer and the second conductor section can be arranged in this next slot in the first layer.

In an advantageous embodiment, it is provided that the conductors of the pair of conductors are set up to have current flowing through them in different circumferential directions, with a respective conductor of the pair of conductors wrapping around the group of stator teeth on different radial sides, so that the Current flow takes place in a respective common groove in both conductors along the same direction.

In an axial flux machine, this means that, for example, a first conductor of the pair of conductors wraps around the group of stator teeth after passing through a first slot on the radial inside of the group of stator teeth, and a second conductor of the pair of conductors wraps around the same group of stator teeth after passing through the first slot the radially outer side of the group of stator teeth. After passing through a next circumferential slot associated with that pair of conductors, the first conductor of the pair of conductors wraps around the next set of stator teeth on the radially outside of the set of stator teeth and the second conductor of the pair of conductors wraps around the same next set of stator teeth on the radially inside of the set of stator teeth.

In this case, the conductors run along a general winding direction which is defined along the circumferential direction of the stator.

This means that the conductors of a conductor pair only run together in sections in the slots. Outside of the slots, the conductors of the respective conductor pair run in different areas on the stator teeth.

The direction of current flow can be defined, for example, from the positive to the negative voltage pole. Due to the fact that the current flow runs in the same direction in a respective common slot in both conductors, the current effects of the two conductors add up, which cause a torque on a rotor associated with the stator.

Furthermore, the stator can be designed for an n-phase electrical rotary machine, with the stator having n pairs of conductors which are each connected to one of the n phases. Here are in a respective groove only Arranged conductor sections of one of the n phases, wherein the conductors of the conductor pair wrap around a group of n stator teeth.

The conductors of the respective conductor pair wrap around the group of n stator teeth on different radial sides.

It cannot be ruled out that several conductor pairs of the same phase are also arranged in the same slot. This also means that the conductor sections of the n conductor pairs are offset by an angular amount in the grooves on the circumference.

Alternatively, the stator can be designed in such a way that conductor pairs of different phases are arranged in the same slot.

In a further advantageous embodiment it is provided that conductor sections of a plurality of windings of at least one conductor pair are arranged in a respective slot.

A turn refers to a region of a conductor that runs once around the circumference. For example, two turns of a pair of conductors can be arranged in one slot. A winding of a pair of conductors can be referred to as a double layer, with a respective conductor of a double layer being referred to as a layer or running in a layer. Correspondingly, two turns of a pair of conductors in a slot can be referred to as two double layers.

A respective pair of conductors has the configurations according to the claimed embodiments.

In particular, the windings along the depth of the groove can be arranged offset parallel to one another next to one another.

The order in which the conductor sections are arranged continues in a respective slot, in the axial direction in an axial flow machine, even when a plurality of windings are implemented. This means that in a sequence of the first section in the first layer in the slot and the second conductor section in the second layer in the second layer in a first turn, this sequence is also implemented in the second turn in the same slot. Correspondingly, it is also provided that the reversal of the sequence of the arrangement of the conductor sections in the next slot in the circumferential direction, which is assigned to the relevant phase, is also implemented for the second turn.

An advantageous embodiment provides that a transition between the windings of the conductors is realized by transition sections of the conductors, each of which has a circumferential length which essentially corresponds to the distance, which is also to be measured along the circumferential direction, between two adjacent grooves in which a conductor runs. is equivalent to..

The transition section can also be referred to as a layer jump. The transition section or the jump in layers makes it possible, for example in the case of an axial flux machine, for the windings of the conductors of the relevant conductor pair to run essentially in planes which are aligned perpendicularly to an axis of rotation of a rotor which, together with the stator, forms an electrical rotary machine, in particular an axial flux machine. trains. The respective transition section or layer discontinuity is a length of the conductor in question, which runs from such a plane or layer into another plane extending parallel to the starting plane, in order to enable the conductor in this layer to also form a turn in one plane , which is aligned perpendicular to the axis of rotation.

For example, the transition section or layer jump can only be formed as one of the radially outer wraps or the radially inner wraps of a group of stator teeth.

The transition section of a conductor can extend into an adjacent plane of the conductor arrangement after a turn has been carried out.

With alternating arrangement of a conductor section of a first conductor in a slot in a first layer or first level and arrangement of a conductor section of a second conductor in the same slot in a second layer or second level, when connecting transition sections of the two conductors to the conductor sections in this Nut the first conductor can be arranged in the second level and the transition section on the first conductor bring the first conductor into a third level, which is aligned parallel to the first and second plane. Correspondingly, the second conductor, when it is located in the second level, can also be guided into the third level through its transition section. In the third and fourth level, the two conductors of the conductor pair again run alternately in the grooves according to the invention.

In this case, the transition sections can be formed in an area of the circumference of the stator in which the electrical connections of the conductors are also realized. Because of this, there is only a very small volume requirement for realizing the transition of the conductors along the axial extent of the stator teeth in an axial flux machine.

In particular, at least the lengths of the conductors that wrap around a group of n stator teeth can be designed without welding of conductor elements to form the lengths.

The routing of the conductors according to the invention makes it possible to run or wind them without connecting welds.

According to a further aspect, the invention relates to a method for producing a stator of an electrical rotary machine according to the invention, in which a stator body, which has a plurality of stator teeth arranged along a circumferential direction and slots formed between the stator teeth, and at least one pair of conductors are provided, and in the Slots conductor sections are arranged by the at least one pair of conductors, so that the pair of conductors forms at least a proportion of windings of the stator. In a respective slot, conductor sections of the conductor pair are arranged parallel to one another along the depth of the slot such that the order of arrangement of the parallel conductor sections in each slot through which the conductors run alternates along the circumferential direction. The conductors of the conductor pair are arranged in such a way that, deviating from a winding direction that basically runs in the circumferential direction, they meander in a direction that runs essentially perpendicular to the circumferential direction in the radial direction and with a respective wrap formed thereby wrap around a group of stator teeth.

Here, too, the vertical direction can also be understood to mean a direction of 60°-120° in relation to an ideal tangent to the circumferential direction.

In addition, the course in this direction can also be curved or designed with at least one slight kink.

An embodiment of a method for producing the winding provides that a plurality of conductors are provided and the conductors are wound on a first sword along a first winding direction such that the conductors wrap around the first sword and then the first sword from the thereby generated winding of the conductor pair is removed.

In particular, the method is used to produce a winding for a stator of an axial flow machine.

A respective winding direction runs in a rotation essentially around the longitudinal axis of the first blade.

A further embodiment of a method for producing the winding provides for providing a first conductor and a further conductor, bending the two conductors into a zigzag shape at least in sections along their length, and moving the further conductor in a combined movement in relation to the first conductor which has a translational movement component along the longitudinal axis of the further conductor and a rotational movement component around the longitudinal axis of the further conductor, so that the further conductor forms the extreme values of the zigzag course around an extreme value axis of the first conductor, which runs through regions of the first conductor, winds around.

A further aspect of the present invention is an electrical rotary machine with a rotor and with at least one stator according to the invention.

In particular, this electrical rotary machine is designed as an axial flow machine. The conductors of the phases are connected to corresponding contacts carrying current of the relevant phase, in particular in a star connection. Current flows through the conductors of a respective pair of conductors in different circumferential directions, with a respective conductor of the pair of conductors wrapping around the group of stator teeth on different sides, so that the current flow takes place in a respective common slot in both conductors along the same direction.

The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, it being noted that the exemplary embodiments shown in the drawings are not limited to the dimensions shown. It is shown in

1: an axial flux machine in an I arrangement in a perspective section;

2: the axial flow machine in an I arrangement in an exploded view;

3 shows a perspective view of a stator core;

4: the stator core with windings;

5: a perspective view of a winding;

6: a winding in a front view;

7: a first side view of the winding;

FIG. 8: a side view of the winding as illustrated in FIG. 7;

9: a third side view of the winding;

FIG. 10: Sectional view along the line of section indicated in FIG. 6;

11: a line element in a double layer, which is designed for two double layers;

12: in the partial illustrations a) to f), the arrangement of individual line elements in the winding;

13: the arrangement of the plus conductor and minus conductor;

14: the stator core with windings and electrical connections;

15: swords with several windings arranged thereon in a perspective view;

16: swords with several windings arranged thereon in plan view; 17: swords with two windings arranged thereon in a perspective view;

18: swords with two windings arranged thereon in plan view;

19: the windings produced in a perspective view;

20: the windings produced in plan view;

21: the swords with windings in a front view;

22: a sword with windings in a view from the side;

23: a sword with windings in plan view;

24: the windings produced in a view from the side;

25: the windings produced in plan view;

26: the winding produced;

27: a line element in a perspective view;

28: the line element in a view from the side;

29: two line elements in a perspective view;

30: a perspective view of a winding;

31: the winding in a view from the side;

32: a line element in a view from the side;

33: a line element in plan view;

34: two line elements connected to one another in a view from the side;

35: the two interconnected line elements in plan view;

36: the winding produced;

37: a stator core with winding in a perspective view; and

38: a stator core with winding in a front view.

First, the general structure of a stator according to the invention will be explained with reference to FIGS.

FIG. 1 shows an axial flux machine in an I arrangement with wave windings in a perspective section, which has a stator 10 on each side of a rotor 2 . The respective stator 10 includes a stator body 11 which includes or forms a stator yoke. The stator 10 has a plurality of stator teeth 12 arranged along a circumferential direction 14. which extend in the axial direction. The stator teeth 12 are separated from one another by slots 15 .

The stator 10 also includes one or more windings 20 of electrical conductors wrapped around the slots 15 and stator teeth 12 . These windings are placed on the stator teeth 12 along a general winding direction 21 that runs along the circumferential direction 14 .

The windings 20 form end windings 22 on the radial inside of the stator teeth 12 and on their radial outside.

Figure 2 shows the same structure as Figure 1, but in an exploded view. The rotor 2 is arranged centrally between two stators 10, each stator 10 having a winding 20 which is designed as a wave winding.

However, the present invention is not limited to the illustrated design of an axial flow machine, but it can also be designed as an H-type, or one-sided axial flow machine with only one stator and only one rotor.

FIG. 3 shows a stator body 11 in a perspective view. The grooves 15 and their depth 16 are clearly visible here.

As Figure 4 illustrates, the configuration of the stator according to the invention provides that linear conductor sections 33 of at least one conductor pair 30 are arranged in the slots 15, which form at least a proportion of windings 20 of the stator, with linear conductor sections 33 of the Conductor pairs 30 are arranged parallel to one another along the depth 16 of the groove 15 and the order in which the parallel conductor sections 33 are arranged in each groove 15, through which the conductors run, alternates along the circumferential direction 14.

A pair of conductors is illustrated in FIG. 4 by the first conductor 31 and the second conductor 32 .

Deviating from the embodiment shown here, the linear conductor sections 33 can also be designed curved or saber-shaped. For conceptual clarification, however, conductor sections shaped in this way are also subsumed below under the term “linear conductor sections”.

Figure 4 shows that the conductors of the conductor pair 30 of the illustrated wave winding deviate from the winding direction 21, which basically runs in the circumferential direction 14, in a direction perpendicular to the circumferential direction 14 running direction or meander in the radial direction. This has the result that the conductors of the conductor pair 30 with loops 34, as illustrated in FIG. 5, each loop around a group of stator teeth 12.

Current flows through the conductors of the conductor pair 30 in different circumferential directions. This is explained using the first pair of conductors 30 .

A first conductor 31 of the conductor pair 30 is referred to as the plus conductor for this purpose. A second conductor 32 of the conductor pair 30 is referred to as the negative conductor for this purpose.

The first conductor 31 forms a first connection 36 of the positive conductor and a second connection 37 of the positive conductor.

The second conductor 32 forms a first connection 38 of the negative conductor and a second connection 39 of the negative conductor.

Said conductors are designed to be connected to respective three phases, with one plus winding and one minus winding per phase.

A respective conductor 31, 32 of the conductor pair 30 wraps around a group 13 of stator teeth 12 on different radial sides, so that the current flow in a respective common slot 15 takes place in both conductors 31, 32 along the same direction.

It can be seen here that the stator 10 not only includes one pair of conductors, but three pairs of conductors, with a third conductor 61 and a fourth conductor 62 forming the second pair of conductors, and a fifth conductor 63 and a sixth conductor 64 forming the third pair of conductors.

However, only sections of conductors of a conductor pair are always arranged in a respective slot 15 .

In addition, it can be seen from FIG. 4 that the conductors of a conductor pair alternate with regard to the axial order in which they are arranged in a slot 15 .

For better clarification of the course of the conductors, FIG. 5 shows the winding assembly produced without the stator teeth.

All conductors are clearly visible here in a perspective view. Furthermore, it can be seen that a respective pair of conductors 30 loops around a group 13 of stator teeth 12 which each includes three stator teeth 12 .

Due to the alternating arrangement of the conductors of a respective conductor pair 30 in the slots 15, it is necessary for these conductors to cross. For this purpose, the conductors form connecting conductor sections 35 which connect the linear conductor sections 35 to one another and ensure that the respective conductor runs back and forth between two arrangement levels between the grooves 15 in which the relevant conductor runs.

For the three phases shown, one phase occupies every third slot 15.

The axially first conductor layer in a relevant slot 15 is alternately assigned a plus or a minus phase. A layer can also consist of several discrete individual wires.

The winding 20 with the formation of two so-called double layers 60 is shown in FIGS. A double layer 60 designates the course of a conductor in two mutually parallel planes. Correspondingly, two double layers 60 comprise four levels.

In order to enable the conductors of the conductor pair 30 to run in the four planes, the conductors each form a transition section 70, as is shown by way of example using the first conductor 31. This transition section 70 allows the first conductor 31 to pass from a second level to a third level.

Such a transition section 70 is also referred to as a layer jump.

FIG. 6 once again shows the realized winding 20 in a side view. A common connection area 40 of the conductors implemented on the circumference is also clearly visible.

Figure 7 clearly shows the arrangement of the conductors 31, 61, 63, 32, 62, 64 and in different levels, namely in a first level 51, a second level 52, a third level 53 and a fourth level 54.

Furthermore, the connecting conductor sections 35 can be seen here, which ensure that the conductors 31, 61, 63, 32, 62, 64 can change between the first level 51 and the second level 52, and between the third level 53 and the fourth level 54 can switch. FIG. 8 shows the same winding 20 in the same side view as FIG. 7, only without clarifying the course of the planes.

FIG. 9 shows a top view of the winding 20 illustrated in FIG.

FIG. 10 shows a sectional illustration according to the course of the section indicated in FIG. Here, too, the connecting conductor sections 35 can be seen in section, which are used for crossing the conductors and at the same time form part of the winding overhangs 22 .

It can also be seen here that the winding overhangs 22 can be designed in such a way that they are not or only slightly wider than the width of a slot 15 in question and accordingly have a small axial space requirement.

In addition, the winding overhangs 22 are also designed radially flat, so that axial flow machines equipped with them can realize a larger radius in the torque-active area.

This principle for designing a wave winding can also be used for radial flux machines.

A winding 20 with two double layers 60 is thus shown, which occupy a total of four layers or planes 51, 52, 53, 54 in the axial direction. An even number of layers or planes is required for this. Since two layers or planes each represent a common structure, two layers that belong together are referred to as a double layer 60 .

The planes 51, 52, 53, 54 shown here do not necessarily have to be planar or even. For example, to follow a conical rotor, these planes 51, 52, 53, 54 could also be conical.

In order to clarify a respective conductor course, FIG. 11 shows the first conductor 31 for one phase in a winding with two double layers in an individual, perspective representation. It can be seen that the linear sections 33 are each followed by connecting conductor sections 35 which guide the first conductor 31 back and forth between individual arrangement levels. After completion of a revolution, starting from a first terminal 36, the first conductor 31 realizes a transition portion 70, the first conductor 31 axially behind the already executed turn brings. There the first conductor again runs in one turn until it ends at its second connection 37 . The first connection 36 and the second connection 37 are essentially in the same angular range.

FIG. 12 shows the implementation of the overall winding in 6 partial illustrations a) to f). Partial representation a) shows the first conductor 31, as has already been explained with reference to FIG. Partial representation b) shows the first conductor 31 and a third conductor 61 . Partial illustration c) shows the first conductor 31, the third conductor 61 and a fifth conductor 63. These conductors all form, for example, a so-called positive conductor of the respective phase. In addition to the conductors shown in partial representation c), partial representation d) now also shows the arrangement of the second conductor 32, which belongs to the same phase as the first conductor 31. As already described, it can also be seen here that linear conductor sections 33 of the first conductor 31 and of the second conductor 32 are arranged in such a way that they can be placed together in slots.

Partial representation e) shows all the conductors already shown in partial representation d) and also a fourth conductor 62 which, together with the third conductor 61, forms a second pair of conductors. Partial representation f) shows all the conductors already shown in partial representation e) and additionally a sixth conductor 64 which, together with the fifth conductor 63, forms a third pair of conductors. In addition, partial representation f) shows that the end windings 22 are approximately as wide as the axial length required for the conductors in the slots.

A winding 20 with two double layers 60 is shown in each of FIGS. 7 to 10, but the winding 20 can also consist of only one double layer or have more than two double layers. The second conductor 32, the fourth conductor 62 and the sixth conductor 64 each form the so-called negative conductor.

It can also be seen in FIGS. 6 to 10 that connecting conductor sections 35 connect to the linear conductor sections 33, which run in the slots 15 bridge a part of the distance to the next belonging to the same phase groove 15 in the circumferential direction, and the radially inner as well as the radially outer end winding 22. Since the to connecting linear conductor sections 33 of a double layer are on different layers or planes, the connecting conductor section 35 also performs the necessary change of position.

To illustrate a pair of conductors 30, the course of the first conductor 31 and the second conductor 32 is shown once again in FIG. Here it can be seen that the linear conductor sections 33 overlap each other along the axial direction, so that they can be represented together in slots. Furthermore, it can be seen that each of the two conductors 31, 32 shown here forms a transition section 70 or layer jump.

FIG. 14 shows the stator 10 with the winding 20 and a corresponding electrical interconnection.

In this case, FIG. 14 shows an advantageous connection of the plus and minus windings, resulting in a star connection of the windings with three connections for a connection to the power electronics. The phase supply or the connection to the power electronics takes place via the first connections of the plus windings, also called plus connections 71 . The individual second connections of the positive windings are each connected individually to the second connections of the associated phase of the negative windings. The first connections 73 of the negative windings are interconnected to form a star connection. This connection ensures that the plus and minus windings of a phase are connected in such a way that the conductor sections in the slots have the same current direction. Compared to a hairpin winding, where a connection has to be made for the conductor in a slot, the wiring effort is reduced to four connection points per phase.

Alternatively, the connection shown can also be used for a series connection 72 . Deviating from the exemplary embodiments presented here, the stator designed according to the invention can also be designed for more or fewer than 3 phases.

Figures 15-26 relate to an embodiment of a method for manufacturing windings of the stator. The process described here relates to the production of windings in two double layers. For this purpose, as shown in FIGS. 15-18, a first sword 80, a second sword 90 and a third sword 100 are aligned in such a way that their longitudinal axes run essentially parallel to one another. The first sword 80 is set up to produce turns of a first double layer. The third sword 100 is set up to produce turns of a second double layer.

The swords each have a geometry that favors the later process steps of bending into a flattened mat and bending into a circular shape.

As Figures 15 and 16 illustrate in different views, around the first sword 80 along a first winding direction 82, here in the mathematically positive sense, the first conductor 31, the second conductor 32, the third conductor 61, the fourth conductor 62, the fifth conductor 63 and the sixth conductor 64 are wound. It makes sense to rotate and move the first sword 80 about its longitudinal axis 81 so that the following windings reach the first sword 80 next to windings that are already present.

With regard to the conductor pair, which includes the first conductor 31 and the second conductor 32 and forms the first phase, it should be mentioned that the third conductor 61 and the fifth conductor 63 are located between the first conductor 31 and the second conductor 32 however, belong to the second phase and the third phase. During the winding onto the first sword 80, the second sword 90 has not yet been brought into position, so that it does not interfere with the winding process on the first sword 80. The second sword 90 is not positioned until the required turns on the first sword 80 have been created. After completing the necessary number of turns, the second blade 90 is positioned next to the first blade 80 and the winding direction is reversed for approximately half a turn. In this way, the conductors are guided over the second sword 90 in a second winding direction 91 which runs in the opposite direction to the first winding direction 82 . By reversing the winding direction, the conductors are pre-bent for the layer jump. After that, said conductors are again wound up along the first winding direction 82 on the third sword 100, which is positioned after said half reverse rotation. If further double layers are required, the number of swords and the carried out windings increased. If there are more than two layer jumps or transitions between double layers, further second swords can be used. After the windings have been produced, the wound conductors can be pressed together to form a winding mat, so that this winding mat has approximately the same axial extent as the depth of the slots in the stator body in which the winding or windings are to be accommodated. This winding mat can still be bent into an annular shape to facilitate insertion into the slots of the stator core.

The implementation of the method is not necessarily restricted to the order of the steps mentioned above.

The use of the second blade 90 and the third blade 100 can be dispensed with in order to implement a winding mat with only one double layer.

The present method can also be used to produce windings for radial flux machines.

For a simplified explanation of the course of the method, the winding processes are shown in FIGS.

It is also clearly evident here that the looping of the second blade 90 with these conductors 31 , 61 forms two transition sections 70 . Figures 19 and 20 show the windings 20 produced after the swords have been withdrawn. It can be seen that the winding structure has been preserved and the bridging sections 70 are also formed.

FIG. 21 shows the 3 swords 80, 90, 100 in a frontal view when the first conductor 31 is being wrapped. It can be seen that the first conductor 31 completely wraps around the first sword 80 and also the third sword 100 . However, the second sword 90, which is located between the first sword 80 and the third sword 100, is only wrapped around at its upper side in a limited angle of wrap 92. Correspondingly, the wraps around the first sword 80 and the third sword 100 form wraps both on a first wrap side 110 and on a second wrap side 111 opposite this first wrap side 110 . The first conductor 31 is guided essentially linearly on flat side surfaces 112 of the swords 80,100. It can be seen that, when the generated winding is equated with a harmonic oscillation, the first wrapping side 110 forms an extreme value range 120 and the second wrapping side 111 forms an opposite extreme value range 120 .

In the extreme value regions 120 lying opposite one another, the winding is designed with a different width in order to adapt its shape to the fact that the distance between the slots in the stator body is greater on the radial outside than on the radial inside.

FIGS. 22 and 23 again show the winding 20 around the first sword 80 in different views.

FIG. 24 shows the winding 20 produced in a side view and FIG. 25 shows the winding 20 produced in a plan view. The extreme value ranges 120 formed by the winding 20 can be seen very clearly in FIG. 24 in particular. Furthermore, it can be seen that each of the two conductors 31, 61 forms meshes 140.

It can also be seen here that the distance between the linear conductor sections 33 within a shaft section is spaced apart from one another in an alternating manner by a first distance 230 and a second distance 231, with the second distance 231 being greater than the first distance 230. This takes this into account that the outer end windings have to bridge larger distances in the circumferential direction than the inner end windings. If this method is used for the stator windings of a radial flux machine, the distances for the two end windings are similar. These may change with the radius on which the winding layer lies, in that the swords used one after the other are designed with different widths for the individual double layers.

Figure 26 shows a winding which includes all six conductors forming the three phases.

Figures 27-38 relate to another embodiment of the method for manufacturing a winding of the stator.

FIG. 27 shows the first conductor 31 in a double layer as an example. There are once again the individual sections of the first conductor 31 can be seen, namely the linear conductor sections 33 as well as the connecting conductor sections 35 and in the sections that are radially furthest inside and outside the extreme value ranges 120.

In a side view, FIG. 28 clearly shows that the connecting conductor sections 35 ensure that the first conductor 31 runs alternately between a first plane 51 and a second plane 52 .

FIG. 29 shows a braid 130, which is formed by the first conductor 31 and the second conductor 32, so that together they result in a plus and a minus phase. These two conductors 31 , 32 form a number of meshes 140 . It can be seen that both conductors 31, 32 are guided alternately in the two arrangement levels. This means that the linear conductor sections 33 of the two conductors 31, 32 are alternately arranged axially at the front and axially at the rear. FIG. 30 now shows a braid 130 which has been supplemented by a third conductor 61, a fourth conductor 62, a fifth conductor 63 and a sixth conductor 64 in the manner described for FIG. These six conductors, set up for the connection of three phases, together form a complete double layer.

FIG. 31 shows this mesh 130 in a view from above.

The procedure for producing such a mesh will now be explained with reference to FIGS. 32-35.

First, as shown in FIG. 32, a first conductor 31 is provided which is in a meander shape or zigzag shape. It can be seen here that a first spacing 230 and a second spacing 231 are realized alternately between adjacent linear conductor sections 33, with the second spacing 231 being greater than the first spacing 230. This leads to different widths of the top and bottom formed as a result Meshes 140 open at the bottom. FIG. 33 makes it clear that the first conductor 31 shown here meanders not only in one plane, but also in the plane running perpendicular thereto, so that the first conductor 31 begins to form a helical thread or a three-dimensional spiral. In a practical implementation, this three-dimensional spiral can also be designed to be significantly flatter than that shown in FIG. In the extreme case, the conductor in Figure 33 is already as flat as it was after it was inserted into the slots of the stator. A central plane 222 leads through the extreme value ranges 120. The Conductor course in wave or spiral form already has features that favor the subsequent steps for forming into a winding mat. The conductor sections for the later inner winding head are shorter/smaller than the conductor sections for the later outer winding head, so that the distances 230, 231 between the conductor sections for the winding grooves are also of different sizes in alternation. The non-circular shape of the three-dimensional helical form is formed in such a way that in the later process steps, the braiding is then flattened to produce the desired contour for forming the inner and outer winding overhangs, as well as the linear conductor sections for the winding grooves.

This means that the zigzag shape is three-dimensional, with the zigzag shape being equated with a harmonic oscillation, linear conductor sections 33 of the conductor in question, which have a positive slope 220, and linear conductor sections of the conductor in question, which have a negative slope 221, on both sides outside of a the central plane 222 running through regions of the extreme values 120 are arranged in the middle. The braid is now created by providing a further conductor 41 of a dual array of conductors which has been preformed in substantially the same way as the first conductor 31 . As indicated in Figures 34 and 35, the further conductor 41 is then moved relative to the first conductor 31 with a combination movement, which combines a translational movement component 210 with a rotational movement component 211, so that the further conductor 41 rotates about its longitudinal axis 200 and is simultaneously moved forward along the longitudinal axis 200 so that its conductor tip 212 penetrates through the shaft of the first conductor 31 in each case. As a result, the further conductor 41 meanders through the meshes 140 of the first conductor 31, in a manner similar to the production of a wire mesh fence, so that these result in a plurality of spatial spirals twisted into one another.

As can be seen from Figure 34, the linear conductor sections 33 also overlap one another.

Figure 36 shows a braid 130, formed from the first conductor 31, a second conductor 32, a third conductor 61, a fourth conductor 62, a fifth conductor 63 and a sixth conductor 64, which according to the above procedure into each other intervention were brought. The fourth conductor 62 and the first conductor 31 have been screwed into one another in the manner described. This means that the fourth conductor 62 corresponds to the further conductor 41 .

The other conductors shown here, ie the second conductor 32, the third conductor 61, the fifth conductor 63 and the sixth conductor 64 have in turn been connected to one another according to the present method in the order shown. Accordingly, this provides three pairs of conductors for connection to three phases that are intertwined.

Deviating from the embodiment shown here, of course, more or fewer pairs of conductors can be intertwined to connect the phases. After the production of this mesh 130, this mesh 130 still has to be bent into a circular shape. In addition, the three-dimensional structures of the individual conductors of this braiding can also be reduced in the axial extent, so that they result in a flat mat that requires less axial space when integrated between the stator teeth.

However, the method is not limited to the order of the individual steps described above. FIGS. 37 and 38 each show a stator 10 in the slots 15 of which the linear conductor sections 33 of a mesh made of the six conductors mentioned above are arranged.

The stator 10 shown here has the special feature that it comprises the six conductors in two double layers, which, however, are not connected to one another by transition sections, as shown in FIG. This is evident from the designation of two first conductors 31 in FIG. 37, for example.

The stator proposed here, the method for its production and the electric rotary machine equipped therewith make it possible to combine high power density and high efficiency with a small installation space requirement for the winding overhangs. Reference character list

1 axial flow machine

2 rotors

10 stator

11 stator body

12 stator teeth

13 group of stator teeth

14 circumferential direction

15 slots

16 depth of groove

20 winding

21 winding direction

22 winding head

30 pairs of conductors

31 first leader

32 second leader

33 linear ladder section

34 wrap

35 connecting conductor section

36 First connection of the positive conductor

37 Second connection of the positive conductor

38 First connection of the negative conductor

39 second connection of the negative conductor

40 common port area

41 other leaders

51 First level

52 second level

53 Third level

54 Fourth Level

60 double layer

61 Third Leader

62 Fourth Leader 63 Fifth Leader

64 Sixth Leader

70 transition section

71 plus connectors

72 Connection for series connection

73 Connection for star connection

80 first sword

81 longitudinal axis

82 first winding direction

90 second sword

91 second winding direction

92 wrap angles

100 third sword

110 first wrapping side

111 second wrapping side

112 flat side surface

120 extreme value range

130 braid

140 stitches

200 longitudinal axis of the second conductor

210 translational motion component

211 rotational component of movement

212 ladder top

220 Positive Slope Section

221 negative slope section

222 center plane

230 first distance

231 second distance

Claims

27 patent claims

1 . Stator (10) of an electrical rotary machine, comprising a stator body (11) which has a plurality of stator teeth (12) arranged along a circumferential direction (14) and grooves (15) formed between the stator teeth (12) and arranged in the grooves (15). Conductor sections of at least one conductor pair (30), which forms at least part of the windings (20) of the stator (10), wherein in a respective slot (15) conductor sections of the conductor pair (30) along the depth (16) of the slot (15) are offset parallel to one another and the order of arrangement of the parallel conductor sections in each groove (15) through which the conductors pass alternates along the circumferential direction (14), and the conductors of the conductor pair (30) deviating from a principle in the circumferential direction ( 14) running winding direction (21) meandering in a direction running essentially perpendicularly to the circumferential direction (14) in the radial direction and with a respective one thereby wrap each formed wrap around a group (13) of stator teeth (12).

2. Stator according to claim 1, characterized in that the conductors of the conductor pair (30) are set up to have current flowing through them in different circumferential directions, with a respective conductor of the conductor pair (30) connecting the group (13) of stator teeth (12) to different wraps around radial sides, so that the current flow takes place in a respective common groove (15) in both conductors along the same direction.

3. Stator according to one of the preceding claims, characterized in that the stator (10) is designed for an n-phase electrical rotary machine, the stator (10) having n pairs of conductors (30) which are each connected to one of the n phases , wherein in a respective groove (15) only conductor sections of one of the n phases are arranged, and the conductors of the conductor pair (30) wrap around a group (13) of n stator teeth (12).

4. Stator according to one of the preceding claims, characterized in that conductor sections of a plurality of windings of at least one conductor pair (30) are arranged in a respective slot (15).

5. Stator according to claim 4, characterized in that the windings along the depth (16) of the groove (15) are arranged offset parallel to one another next to one another.

6. Stator according to claim 3-5, characterized in that a transition between the turns of the conductors is realized by transition sections (70) of the conductors, each having a circumferential length which corresponds to the distance between two adjacent slots in which a conductor runs , is equivalent to.

7. Stator according to claim 6, characterized in that the transition section (70) of a conductor extends into an adjacent plane of the conductor arrangement after execution of a turn.

8. Stator according to one of Claims 3 to 7, characterized in that at least the lengths of the conductors which wrap around a group (13) of n stator teeth (12) are designed without welding conductor elements to form the lengths.

9. A method for manufacturing a stator (10) of an electrical rotary machine according to any one of claims 1 to 8, wherein a stator body (11) arranged along a circumferential direction (14) and a plurality of stator teeth (12) and formed between the stator teeth (12). Has grooves (15), and at least one pair of conductors (30) for are made available, and conductor sections of the at least one conductor pair (30) are arranged in the slots (15), so that the conductor pair (30) forms at least a proportion of windings (20) of the stator (10), with in a respective slot (15) Conductor sections of the conductor pair (30) along the depth (16) of the groove (15) are arranged offset parallel to one another in such a way that the order of arrangement of the parallel conductor sections in each groove (15) through which the conductors run, along the Circumferential direction (14) alternates, and wherein the conductors of the conductor pair (30) are arranged such that they deviate from a fundamentally in the circumferential direction (14) running winding direction (21) in a substantially perpendicular to

Circumferential direction (14) meandering in the radial direction and with a respective looping thus formed loop around a group (13) of stator teeth (12).

10. Electrical rotary machine, comprising a rotor and at least one stator (10) according to any one of claims 1 to 8.