WO2022226569A1

WO2022226569A1 - Stator for an electrical machine

Info

Publication number: WO2022226569A1
Application number: PCT/AT2022/060143
Authority: WO
Inventors: Robert MIESBAUER
Original assignee: Miba Emobility Gmbh
Priority date: 2021-04-28
Filing date: 2022-04-27
Publication date: 2022-11-03
Also published as: DE112022002412A5; AT524972A1

Abstract

The invention relates to a stator (1) for an electrical machine, comprising a hollow-cylindrical stator core (2) having a first and a second axial end face (13a, 13b) and having a plurality of receiving grooves (4) distributed along a circumferential direction (10) of the stator core (2). The stator winding (14) comprises at least two parallel current paths which each have, viewed towards one of the axial end faces (13a, 13b) of the stator, a helical and stepped profile in relation to the circumferential and radial direction (10, 12) of the stator. The current-path ends of the current paths end at a receiving groove (4) inside a magnetic pole portion, which magnetic pole portion is directly adjacent, in relation to the circumferential direction (10) of the stator, to a magnetic pole portion in which the current-path starting points of the current paths start. The invention therefore provides for a stator (1) for electrical machines, the connectors of which stator, for the electric winding, are located in a segment of its circumference that is as narrow as possible, it being possible for the electric winding to be nevertheless formed with as low a number of differently formed pin conductor elements as possible.

Description

STATOR FOR AN ELECTRICAL MACHINE

The invention relates to a stator for an electrical machine and an electrical machine which has such a stator as specified in the claims.

AT521589A1 describes a stator for an electrical machine, which comprises an essentially hollow-cylindrical laminated core with a plurality of receiving slots arranged in a distributed manner. Several electrical conductor sections formed by shaped rods per receiving groove form a stator winding with at least two partial windings. The at least two electrical partial windings are each formed by at least a first and a second winding segment electrically connected in series, with conductor sections of the first winding segment being electrically connected to one another by means of first and second electrical connection sections such that a helical current path is formed along a first radial direction to the longitudinal axis of the laminated core and conductor sections of the second winding segment are electrically connected to one another by means of first and second electrical connection sections such that a second helical current path is defined along an opposite, second radial direction to the longitudinal axis of the laminated core. This loop-like structure of a winding using shaped bar technology enables high-volume production of stators with high and consistent manufacturing quality.

With the specified winding scheme, however, it is difficult to keep the electrical connections of the individual partial windings or the complete stator winding in a narrow, sectoral section of the stator.

The object of the present invention was to overcome the disadvantages of the prior art and to provide a stator for electrical machines or an electrical machine the electrical winding should nevertheless be constructed with the smallest possible number of differently designed shaped bar conductor elements.

This object is achieved by a stator and an electrical machine according to the claims. A stator constructed according to the invention for an electrical machine comprises

An essentially hollow-cylindrical stator core with a first and a second axial end and with a plurality of receiving grooves arranged along a circumferential direction of the stator core and extending along a central axis of the stator core ,

- Several electrical conductor sections formed by shaped rods per receiving groove, which conductor sections form a stator winding through predetermined electrical connections, and which stator winding comprises several layers of the conductor sections that are immediately adjacent in the radial direction to the central axis of the stator core, and these conductor sections are predetermined by the predetermined electrical connections form electrical current paths in this form bar stator winding, and the stator in the circumferential direction distributed defines a plurality of magnetic pole sections, wherein

- the stator winding comprises at least one phase winding, which comprises at least one phase winding at least two current paths,

- and each current path has a dedicated input terminal, a current path start, a current path end and a dedicated output terminal, where

- At least one of the current paths begins with its current path starting from one of the radially outer layers and then alternates or jumps in layers and also runs in the circumferential direction at least over a section of the circumference of the stator to the radially innermost layer, with the current path at With each of these changes in position, there is a transition from one of the magnetic pole sections of the stator to an immediately adjacent pole section in the direction of the circumference of the circle, and the current path changes the positions in a continuously constant radial direction by a layer jump distance of "one" until the radially innermost position is reached, so that the current path takes an approximately helical and stepped course with respect to the circumferential and radial directions of the stator, and where

- the running direction of the electric current path at the radially innermost layer with respect to the circumferential direction of the stator core is reversed by a reversing conductor section, and then the electric current path starting from the radially innermost layer alternates the layers in layers and also in the circumferential direction at least over a partial section of the Circumference of the stator running while in the radial direction to only one layer running offset, and again with a layer jump distance of "one", with a snail and step-like progression in relation to the circumferential and radial direction of the stator, back towards a radially further outward layer, i.e. to one of the several radially outer layers, where

- the current path has at least one helical and stepped course in the radial direction towards the central axis of the stator core and also at least one helical and stepped course in the radial direction away from the central axis of the stator core, i.e. a current path runs at least once helically and once stepwise in the radial direction inwards and at least once spirally and stepwise in the radial direction outwards, and wherein

- the current path ends with its current path end at a receiving groove within a magnetic pole section, which magnetic pole section is arranged immediately adjacent to a magnetic pole section in relation to the circular circumferential direction of the stator, in which the current path begins with its current path start, These pole sections, which are directly adjacent in the direction of the circumference of a circle, have different magnetic poles, so that the start and end of the individual current paths are positioned in sectors or sections of the stator that are close to one another.

However, it is also possible to reverse the course of the helical and stepped course of at least one of the current paths with respect to the radial direction to the central axis of the stator core, and reverse positioning with respect to the start and end of the current path is also possible of at least one of the electrical current paths possible.

The measures according to the invention enable all connection points or connection pins of the parallel current paths of one or more phase windings to be grouped in a relatively small sector of the winding overhang. Since the outputs in particular, but also the inputs of the individual parallel current paths, are close together, the interconnection of the same, for example to a star point of a three-phase star winding, is made easier. Such a neutral point connector can thus be kept as short as possible or other connection conductor elements—in particular what are known as busbars—can also be reduced. As a result, an advantageous saving of conductor material for the stator winding and of the weight of the stator can be achieved. In addition, the number of different shaped rods and conductor sections or hairpins to be inserted into the stator core remains small. This favors a high-volume, fully automated production of such a stator. In addition, the available space can be better utilized and the winding overhangs of the stator can be designed as compactly as possible thanks to the specified winding scheme. In addition, there is great flexibility with regard to the interconnection options with such a form rod winding, for example with regard to the possible number of parallel current paths, with regard to the possible number of winding pitches and the number of conductors per slot.

It is also practical for the specified winding scheme if a course direction of the reversing conductor sections on the radially innermost layer and on the radially outermost layer in relation to the circumferential direction of the stator is selected in such a way that the current path start and the current path end of all current paths of a dedicated phase winding come to rest within a common connection section of the stator winding, which extends over a maximum of two immediately adjacent magnetic pole sections in the circumferential direction of the stator. That is, the inversion conductor portions point in the positive direction (clockwise) or in the negative direction (counterclockwise) with respect to the circumferential direction without performing a layer jump. As a result, an electrotechnically fully symmetrical winding can be realized with a few differently shaped reversal shaped rods and with standard shaped rods, for example classically shaped hairpins.

In particular, a course direction of the reversing conductor sections at the radially innermost layer and at the radially outermost layer with respect to the circumferential direction of the stator can be selected in such a way that the current path start and the current path end of all current paths of a phase winding within the come to lie in the same position or come to lie in two immediately adjacent positions in the radial direction. This can be systematically achieved by appropriate selection of the reversal s -Leitrab sections in the positive direction or the negative direction.

The specified winding scheme makes it possible in a structured manner that at least one of the current paths or all current paths is on the one hand between the input connection and the current path start and on the other hand between the current path end and the output output connection, each have transition conductor sections, which transition conductor sections run towards one another in the circumferential direction in such a way that the input connections and the output connections of these current paths come to lie within a single magnetic pole section of the stator and are therefore positioned spatially close to one another. This is done without the need for extensive transition conductor sections or so-called "busbars", which means that the end windings of the stator winding can be implemented as compactly as possible, with little conductor material and with low weight.

In particular, it is expedient if each of the at least two current paths extends over more than 360° of the circumferential direction of the stator core in a view of one of the two axial ends of the stator core in order to achieve a structured and scalable construction of the stator winding. The measure that each of the at least two current paths runs more or less in a snail or spiral shape in view of the two axial ends of the stator core can also contribute to this.

In the case of an inverted conductor section, a layer position of the current path is retained unchanged, ie the inverted conductor section extends along the radially innermost or along the radially outermost layer. Accordingly, it forms part of the radially innermost or outermost layer or it remains within the radially innermost or outermost layer.

It is also expedient if each current path comprises an even number of current path sections running in the radial direction and also in the circumferential direction of the stator, in particular two, four, six or more such current path sections, and if between successive current path sections the mentioned reversal conductor sections are executed. As a result, the current path beginnings and the current path ends of the respective current paths come to lie in a close proximity to one another and compact positioning of the respective connection points can be ensured.

The winding scheme is also characterized in that the stator winding comprises at least two electrical current paths running in parallel and each current path beginning of these electrical current paths is formed in a first magnetic pole section of the stator and each current path end of these electrical current paths in a second magnetic Pole portion of the stator is formed, which is immediately adjacent to the first magnetic pole portion in the circle circumferential direction of the stator. This local concentration of the current path beginnings and the current path ends can be safely achieved with the given current path courses. In particular, the structure of the stator winding or the two axial winding overhangs is as regular as possible. The simple insertion sequences of the form rod ladder elements enable process-reliable automation and also rapid production processes.

Complicated plug-in sequences can also be avoided in that the reversing conductor sections are formed exclusively in the radially innermost and exclusively in the radially outermost layer of the stator winding. In addition, the creation of winding heads that are as uniform as possible is supported.

It can also be expedient if all reversal conductor sections are designed at that axial end of the stator core at which the conductor sections of the stator winding are connected to one another in one piece or in the shape of a roof or bow. In particular, all of the reversal conductor sections may be associated closest to the so-called "hairpin roof" side of the stator. The opposite, so-called welding side of the stator thus remains as regular as possible or absolutely regular, as a result of which automated welding processes can be carried out easily and reliably.

In accordance with the specified winding scheme, the conductor sections that are electrically connected to one another form a wavy and ring-like course of the electrical current paths, which wavy course is defined by alternating changes in the current paths between the first and the second axial end of the stator core and which ring-like course is defined by a simultaneous Extension of the current paths is defined along the circumferential direction of the stator core. Almost all combinations of connections can be realized with this winding scheme. Even a chord does not prevent a fully symmetrical winding.

The specified winding pattern also makes it possible for all of the input and output connections of the stator winding to be formed either on the first or on the second axial end face of the stator core and also within a partial section of the circumference of the stator core of a maximum of 90°. This with a small number of different shaped rod conductor elements and with transition conductor sections with minimal lengths required.

It is expedient if the stator winding has a three-phase or multi-phase design and comprises three or more phase windings each extending in the circumferential direction, and if each phase winding comprises two or more electrical current paths running in parallel. As a result, a high electromechanical performance of the stator or an electrical machine equipped with it can be achieved, with its construction being clearly structured and being able to be manufactured in large numbers with a high degree of automation.

The object of the invention is also achieved by an electrical machine comprising a stator and a rotor, the stator being designed in accordance with one or more of the preceding statements. The advantages and technical effects that can be achieved in this way can be found in the preceding and following parts of the description.

For a better understanding of the invention, it is explained in more detail with reference to the following figures.

They each show in a greatly simplified, schematic representation:

1 shows a perspective view of a stator with a stator core and a three-phase stator winding, each of the three phase windings comprising four current paths;

FIG. 2 shows the stator according to FIG. 1 in the region of its upper or first winding overhang with the connections for the stator winding which are closely grouped sectorally and also positioned in a structured manner;

3 shows the stator according to FIG. 1 in the area of its lower or second winding overhang with numerous welding points for the electrical connection of the essentially U-shaped conductor sections of the stator winding;

FIG. 4 shows the stator according to FIG. 1 in plan view; FIG.

FIG. 5 shows the stator according to FIG. 1 in a view from below; FIG. 6 shows the winding diagram for the stator according to FIGS. 1-5 in unrolled matrix depiction.

FIG. 7 is a perspective view of the current path A made of form rod conductor elements, created according to the winding diagram in FIG. 6;

8 shows the current path A according to FIGS. 1, 6 and 7 in its state taken up in the stator core;

FIG. 9 shows a top view of FIG. 8 with the course of the current path A including its input and output connections;

10 shows the current path B according to FIGS. 1 and 6, including its input and output connections;

11 shows the current path C according to FIGS. 1 and 6, including its input and output connections;

12 shows the current path D according to FIGS. 1 and 6, including its input and output connections;

13 shows a second exemplary embodiment of the winding scheme comprising three current paths in each of three phase windings, only the course of the first phase winding being illustrated;

14 shows a third exemplary embodiment of the winding scheme, comprising two current paths in each of a total of three phase windings, only the course of the first phase winding being illustrated.

As an introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numbers or the same component designations, and the disclosures contained throughout the description can be transferred to the same parts with the same reference numbers or the same component designations. The position information selected in the description, such as top, bottom, side, etc., is related to the directly described and illustrated figure and these position information are to be transferred to the new position in the event of a change in position. In Figs. 1-3, a stator 1 is shown in different oblique views and in Figs. 4, 5 this stator is shown in plan view and in a view from below. The stator 1 comprises a substantially hollow-cylindrical stator core 2, which can be out in particular as a laminated core. In the stator core 2, a plurality of receiving grooves 4 are distributed in the direction of the circumference 10. The stator core shown as an example comprises a total of 48 receiving slots. The receiving grooves 4 are designed to be continuous in the axial direction 11 of the stator core 2 . Several electrical conductors 8 in and on the stator core 2 form an electrical winding of the stator 1 . For this purpose, several electrical conductors 8 are bent in a defined manner to form an electrical coil or winding in the circumferential direction 10 of the stator core 2 and corresponding electrical conductors 8 are electrically connected to one another.

The receiving grooves 4 of the stator core 2 are either open in relation to a radial direction 12 to the central axis 3 in the direction of the central axis 3 of the stator 1, or are narrowed according to the example. These narrowed openings represent gaps 5 on the inner jacket surface of the essentially hollow-cylindrical stator core 2. Those sections of the stator core 2 which delimit the receiving grooves 4 in the direction of the central axis 3 with regard to the free cross section are also referred to as tooth tips 6 of the stator core 2. The groove bases 7 of the receiving grooves 4 adjoin the opposite side of the tooth tips 6, also called the yoke side. The exact number of receiving grooves 4 and the electrical conductors 8 received therein depends on the desired electromechanical design of the electrical machine. In the illustrated embodiment, eight conductors 8 or eight conductor sections La or Lb are arranged per recording menut 4 .

In principle, the receiving grooves 4 can have a wide variety of cross-sectional shapes, with corresponding, essentially rectangular or trapezoidal cross sections of the receiving grooves 4 having proven suitable for receiving electrical conductors 8 with a substantially rectangular cross section. To insulate the individual electrical conductors

8 to each other and to the stator core 2, it is necessary to have at least one insulation layer

9 to be provided on the lateral surface of the conductors 8, the electrical conductors 8 being encased at least within the stator core 2 with an insulating layer 9, respectively.

The essentially hollow-cylindrical stator core 2 has a first and a second axial end 13a, 13b. The electrical conductors 8 in the receiving grooves 4 are preferred formed by metallic shaped rods, preferably made of copper or another electrically highly conductive material. These shaped rods form a plurality of electrical conductor sections La, Lb, which extend at least within the respectively assigned receiving grooves 4, as can best be seen by looking at FIGS. 1 and 6 together. This Leiterab sections La, Lb can be defined by so-called I-pins or be formed by so-called hair pins. In the case of hairpins, the conductor sections La, Lb represent the two legs of this essentially U-shaped or U-shaped conductor segment.

The electrical conductor sections La, Lb are arranged several times in each of the receiving grooves 4 and the planned stator winding 14 is constructed by predetermined electrical connections between the circularly positioned conductor sections La, Lb, which stator winding 14 is used to generate a circulating magnetic field when the stator 1 is applied with single- or multi-phase electrical energy. As can be seen by way of example from FIGS. 1-5, such a stator winding 14 when ready for use has several immediately adjacent layers L of conductor sections La, Lb in the radial direction 12 to the central axis 3 of the stator core 2 . Single-phase alternating current or multi-phase alternating current (three-phase current) is supplied via dedicated connection points on the stator winding 14.

In the case of the stator winding 14 according to the example, a total of eight layers LI to L8 are provided. The layers LI to L8 are made up of a plurality of conductor sections La, Lb positioned in the receiving grooves 4 . Typically, a practical stator 1 has an even number of layers L, preferably from 4 layers, in particular between 4 and 12 layers. The diameter of the stator core 2, the number of trained recording grooves 4, the number of layers L, and the axial length of the stator 1 or stator core 2 are essentially dependent on which performance data are required or which physical requirements are to be built electrical machine exist.

The three-phase stator winding 14 shown in FIGS. 1-5, whose winding scheme was abstracted and illustrated in part in FIG. 6, includes, for example, four current paths A, B, C, D per phase winding PW1, PW2, PW3. A stator 1 constructed according to the invention or its stator winding 14 comprises at least two current paths A, B for each phase winding PW. In particular, ten or more current paths can be provided for each phase winding PW be. The respective current paths can be connected in series and/or in parallel for each electrical phase winding. With the specified winding scheme, a formation of single-phase or multi-phase stator windings 14 with more than two current paths per phase winding development PW is possible.

The current paths representing individual partial windings of the stator winding 14 from an electrical point of view can therefore be connected in series and/or in parallel, depending on the requirement or power requirement, or can be switched accordingly by a control unit. In the case of the

6, only a single phase winding PW1 or a single phase winding of a stator winding 14 that is provided overall in three phases is shown for the sake of better clarity.

6 shows an advantageous winding diagram for a phase winding or for the phase winding PW1 of an example of an eight-pole stator winding 14 . This phase winding PW1 includes four partial windings or four electrical current paths A, B, C, D. These current paths A-D can also be referred to as winding branches or as parallel paths. In this stator 1, each of the current paths A-D extends over more than 360° but less than 540° of the annular stator core 2.

The stator core 2 according to FIGS. 1-6 has, for example, 48 receiving grooves 4, each of the receiving grooves 4 having eight conductor sections La or Lb or receiving them, so that the stator winding 14 has a total of eight layers L, which are labeled LI to L8 are net. Accordingly, a stator winding 14 or a phase winding PW1 with a total of eight layers L is shown. The position L1 can be understood as the air gap 5—FIG. 1—closest or radially innermost position and the position L8 can be understood as the groove base 7—FIG. 1—closest or radially outermost position L8 . The illustrated stator winding 14 or phase winding PW1 has a so-called fractional hole number q=2. This means that the number of receiving slots 4 occupied by conductor sections La or Lb per magnetic pole section N or S, per electrical phase or phase winding PW and per current path AD is exactly “two”. This can also be seen in FIG. 6 based on groups of two of receiving grooves 4, which are provided with cross-hatching. To construct a total of three-phase stator winding 14, the sections or receiving grooves 4 shown as unoccupied in FIG. In particular, the structure of the phase winding PW 1 shown is repeated for phase U of a three-phase voltage source, essentially also for phase V and for phase W in the remaining receiving slots 4 of the stator core 2. In particular, only a lateral offset or slot offset is to be provided or to be taken into account, and repeats the basic structure or the scheme of the phase winding PW1 for the phase U in the same way for the phase winding PW2 of the phase V and for the phase winding development PW3 of the phase W. The phase windings PW2 and PW3 for the Phases V and W are not included in the representation according to FIG. 6 only for the sake of better clarity. In particular, it should be noted that FIG. 6 shows only one phase winding PW1, for example for phase U. The complete, three-phase stator winding 14, as can be seen in FIG. 1, is to be connected to a three-phase voltage source, with a magnetically eight-pole stator 1 being formed or an eight-pole rotating magnetic field being established.

Each of the current paths A-D of the stator winding 14 and the phase windings PW1-PW3 is formed by a plurality of series-connected conductor sections La and Lb. These conductor sections La and Lb can be part of an integrally constructed or one-piece line segment, in particular a so-called hair pin, as illustrated in FIGS. 1, 6 and 7. Alternatively, the Leiterab sections La and Lb can be formed by so-called I-pins. Accordingly, the Leiterab sections La and Lb by the legs of a substantially U-shaped line s segments, in particular by a so-called hair pin - be defined - Fig. 6, 7. However, the conductor sections La and Lb can also be defined by the middle section of so-called I-pins, which are electrically connected in series.

The current paths A-D are each formed by a plurality of conductor sections La and Lb connected in series, with electrical connection sections VBa, VBb between conductor sections La, Lb electrically connected in series being the first and the second axial end 13a,

13b of the stator core 2 - Fig. 1 and 7 - are associated closest. The first connection sections VBa form a one-piece electrical connection between directly consecutive conductor sections La and Lb. In contrast, the second Connecting sections VBb an electrical connection between a conductor section Lb of a first pair of shaped bars 16 and a serially adjoining conductor section La ei nes further pair of shaped bars 16 from.

According to Fig. 7, the two conductor sections La and Lb are electrically connected to one another in series and in one piece by means of the connecting section VBa and thereby define a one-piece pair of shaped bars 16. Such a pair of shaped bars 16 can be connected to a serially connected or directly adjacent Form rod pair 16 are electrically connected in series, so that a total of a so-called wave winding 15 can be constructed. Such a wave winding 15, which is part of the current paths A-D, runs alternately between the axial end faces 13a, 13b and at the same time in the circumferential direction 10 of the stator core 2, as illustrated in FIGS. 1 and 7 by way of example.

6, the first connecting portions VBa are represented by solid lines or arrows, while the second connecting portions VBb are represented by solid lines or arrows with a centrally arranged rectangle with dot shading. The lines or arrows without a rectangle can be associated with the first axial front end 13a, while the lines or arrows with a centrally located rectangle are mentally assigned to the second axial front end 13b of the stator 1 (FIG. 1).

The rectangles with dot hatching shown in FIG. 6 symbolize contacting points, in particular welding points, within the second electrical connection sections VBb, as can be seen above all in FIGS. The conductor sections La and Lb provided according to FIG. 6 are thus partial sections of so-called flair pins, as illustrated by way of example in FIG. The zones or fields with diagonal hatching shown in FIG. 6 each show the current path beginnings Ai-Di of the respective current paths A-D, while the zones or fields with vertical hatching represent the respective current path ends Ao-Do of the respective current paths A-D. These hatching assignments also apply to the winding s schemes according to FIGS. 13 and 14.

The conductor bar pairs symbolized in Fig. 6 with the same end numbers, for example Al-Al, A2-A2, A3-A3, Bl-Bl, Cl-Cl, etc. each form a one-piece shaped bar pair 16, whose first conductor section La is arranged in one of the receiving grooves 4 and whose second conductor section Lb is arranged in a receiving groove 4 of the stator core 2 that is spaced apart therefrom.

The winding diagram for the phase winding PW1 illustrated in FIG. 6, which is structurally implemented in FIGS. 7-12 using the current paths A-D, has the following structure or the following courses: Each of the current paths A, B, C, D of the phase winding PW1 has an input terminal Al-Dl, a current path start Ai-Di, a current path end Ao-Do and an output terminal A2-D2.

The current paths A, B, C, D begin with their current path beginnings Ai-Di at one of the radially outer layers L8-L2 and then run in layers alternating or jumping and also in the circumferential direction 10 at least over a section of the circumference of the stator to to the radially innermost layer LI. With each of these changes in position, the current paths A-D also transition from one of the magnetic pole sections S or N of the stator to an immediately adjacent pole section N or S in the direction of the circumference of the circle. The current paths A-D change the layers L in a continuous or continuously constant radial direction by a layer jump width of "one" until the radially innermost layer LI is reached. The layer jumps are thus unidirectional until the radially innermost layer LI is reached. Accordingly, each of the current paths A-D assumes an essentially helical and stepped course in relation to the circumferential direction 10 and radial direction 12 of the stator 1, as can be seen above all from FIGS. 8-12 in conjunction with FIG. In the unwound matrix representation according to FIG. 6, this is represented as a staircase-shaped course of the current paths A-D of the stator winding 14.

The direction of each of the electrical current paths AD is after reaching the ra dial innermost layer LI with respect to the circumferential direction 10 of the stator core 2 by each Weil at least one reversal s -Leiterab section 17 reversed (Fig. 6). Then the electrical current paths AD, starting from the radially innermost layer LI, alternate in layers with a layer jump distance of "one" and also run in the circumferential direction 10 over at least a partial section of the circular circumference of the stator and are offset in the radial direction by only one layer L (Fig 6), again with a helical and step-like progression with respect to the circumferential and radial direction 10, 12 of the stator, back towards a radially further outward layer L2-L8. This return takes place to one of the radially outer layers L of the stator winding 14. In particular, in the quasi-unrolled stator representation according to FIG -L2 towards the radially innermost layer LI, or vice versa. Accordingly, all current paths AD of the phase winding PW 1, starting from one of the radially outer layers L of the phase winding PW, migrate in a helical manner, i.e. with a gradually decreasing radius, from radially outer sections of the holzylindri's stator core 2 in the direction of radially inner sections of the stator core 2, as best seen in Figs. 9-12. However, a reverse, snail-shaped course is also possible, that is to say starting from the radially inner sections of the receiving grooves 4 or of the stator core 2 in the radial direction outwards.

In particular, the current paths A-D each have at least one helical or stepped section in the radial direction to the central axis 3 of the stator core 2 and also each have at least one helical or stepped course in the radial direction away from the central axis 3 of the stator core 2, as shown here can best be inferred from the opposite directional arrows in FIG. This means that each of the current paths A-D runs at least once inward in the radial direction 12 in a helical and stair-like manner and at least once outward in a helical and stair-like manner in the radial direction 12 . In the specific exemplary embodiment according to FIG. 6, the four current path sections in each of these four current paths A-D run twice radially in the direction of the central axis 3 and twice radially away from the central axis 3 for all four current paths A-D, so that a total of two reversal conductor sections 17 - shown in dashed lines are implemented on the radially innermost layer LI and, by way of example, a reversing conductor section 18 is made on the radially outermost layer L8. This radially outer reversal section 18 extends, for example, between A8-A8 in the current path A of the stator winding 14 according to FIG.

As is also best seen in FIG. 6, all current paths AD end with their current path ends Ao-Do, which are relevant in terms of electromagnetics, at a receiving groove or at two immediately adjacent receiving grooves within a common magnetic pole section N or S, which is magnetic Pole section with respect to the circular circumferential direction 10 of the stator to a magnetic pole section S or N, in which the current paths AD begin with their current path beginnings Ai-Di, immediately adjacent. These pole sections N, S, which are immediately adjacent in the circumferential direction 10, are poled differently.

Alternatively, all or some of the current paths A-D of the phase winding PW can be reversed with respect to the direction of the helical and stepped rotation, in particular with respect to the radial direction 12 to the central axis 3 of the stator core 2. Alternatively, all or some of the current paths A-D can be constructed in reverse with respect on their current path beginnings Ai-Di and their current path ends Ao-Do.

For the sake of better clarity, the courses of the electrical conductors 8 between the respective receiving grooves 4 and the axial front ends 13a, 13b of the stator core 2 were illustrated in FIGS. 6 and 7 only with reference to the current path A. With regard to the current paths B-D, only the receiving grooves 4 occupied by the respective current path B, C and D are shown in FIG.

By suitably selecting the respective course direction of the reversal conductor sections 17,18 on the radially innermost layer LI and on the radially outermost layer L8 in relation to the circular circumference direction 10 of the stator, it can be achieved with the specified winding scheme that the current path start Ai -Di and the rung end Ao-Do of all rungs A, B,

C, D of a phase winding PW1, PW2 and/or PW3 come to lie within a common, sectorally narrow connection section 19 of the phase winding PW1, PW2, PW3 or the stator winding 14 (FIGS. 1, 2). In particular, this winding scheme makes it possible for the connection section 19 for the entire stator winding 14, which is designed for example in three phases, to extend over a maximum of two magnetic pole sections N and S that are immediately adjacent in the circumferential direction 10 of the stator, as can be seen from a synopsis of Fig. 1 and 6 can be seen. Extensive scattering of the individual current path beginnings Ai-Di and the individual current path ends Ao-Do in relation to the circumference of the stator core 2 can advantageously be avoided. In particular, the specified winding scheme can be used to ensure that all input and output connections Al-Dl, A2-D2 of the stator winding 14 are formed either on the first or on the second axial end face 13a or 13b of the stator core 2 and also within a partial section of the circumference of the Stator core 2 are arranged by a maximum of 90 °, as shown in Figs. 1, 2 is shown. Through the winding scheme explained and through a suitable choice of the course direction of the reversing conductor sections 17, 18 on the radially innermost layer LI and on the radially outermost layer L8 with respect to the circumferential direction 10 of the stator, it is also possible for the respective current path Beginning Ai-Di and the respective current path end Ao-Do of all current paths A, B, C, D of a phase winding PW1, PW2, PW3 or the stator winding 14 come to lie within the same layer L or at least in two in radi aler Direction immediately adjacent layers L come to rest (Lig. 6).

The direction in which the reversing conductor sections 17, 18 run is to be understood as a routing of serially connected current path sections either radially further inwards or radially further outwards in comparison to the current path section that has arrived at the radially innermost layer LI, as shown in Fig. 6 can be taken from the current paths A and B as an example.

With the specified winding scheme or winding course, it can be achieved that the radial layer offset between the start of the current path and the end of the current path of each individual current path, i.e. between Ai-Ao, Bi-Bo, Ci-Co or Di-Do, with each of the current paths AD is either "zero" or at most "one", as is illustrated in all the exemplary embodiments. The connection pairs of some current paths A-D are therefore arranged within a common layer L, while the connection pairs of other current paths A-D can be arranged in layers L that are immediately adjacent in the radial direction, as can be seen above all from Lig. 6 .

Furthermore, it can be provided that at least one of the current paths A-D or all current paths A-D is on the one hand between the input connection Al-Dl and the respective current path start Ai-Di, and on the other hand between the current path end Ao-Do and the respective output connection A2-D2, each have transition conductor sections 20, 21 (Lig. 6). These transition conductor sections 20, 21 are aligned towards one another or running towards one another in the circumferential direction 10 in such a way that the input terminals A1-D1 and the output terminals A2-D2 of these current paths A-D within a single magnetic pole section N or S of the stator 1 lie, as can be seen in the right-hand edge section of lig. 6 using the common pole section N.

Each of the at least two current paths, for example each of the at least four current paths AD, runs in a top view of the two axial ends 13a, 13b of the stator core 2im essentially helical or helical, as best seen in Figs. 8-12. The extent of this course in relation to the circumferential direction 10 of the stator 1 is more than 360° in each case, but less than 540° in each case.

6, 13 and 14, in each of the reversing conductor sections 17, 18, a layer position of each of the existing current paths A-D, A-C and A-B is maintained unchanged. The respective reversal s-conductor sections 17, 18 thus extend along the radially innermost layer LI or along the radially outermost layer L8 or L4. This means that they form part of the radially innermost or outermost layer L or remain within the radially innermost or outermost layer L from an electrical point of view.

As can also be seen from each of the winding diagrams according to FIGS. 6, 13 and 14, each current path A-D, A-C or A-B comprises an even number of current path sections running in the radial direction 12 and also in the circumferential direction 10 of the stator 1. in particular two, four, six or more such current path sections. The reversal conductor sections 17, 18, in which reversal conductor sections 17, 18 do not change the layer position, are implemented between the current path sections electrically connected in series or series.

As can also be seen from each of the winding diagrams according to FIGS. 6, 13 and 14, the stator winding 14 comprises at least two electrical current paths A-D, A-C and A-B running in parallel and each current path start Ai-Di of these electrical current paths A-D, A-C and A-B is formed in a first magnetic pole portion S or N of the stator 1. Each current path end Ao-Do of these electric current paths A-D, A-C and A-B is formed in a second magnetic pole portion N or S of the stator 1 which is immediately adjacent to the first magnetic pole portion in the circumferential direction 10 of the stator 1 . If at least two reversing conductor sections 17, 18 are present between the individual current path sections, these are formed from an electrical point of view exclusively in the radially innermost layer LI and exclusively in the radially outermost layer L4 or L8 of the stator winding 14.

6, 13 and 14 and in conjunction with the perspective view of FIG. 7 can be seen, the electrically interconnected conductor sections or conductors 8 form wavy and also ring or basket-like profiles in the electrical current paths AD, AC and AB. The wavy course is defined by alternating changes in the current paths AD, AC and AB between the first and the second axial end 13a, 13b of the stator core 2 and the ring-like course is defined by a simultaneous extension of the current paths AD, AC and AB along the circumferential direction 10 of the stator core 2 is defined.

As can also be seen from FIGS. 6, 13 and 14, all reversal conductor sections 17, 18 in the current paths A-D, A-C and A-B can be implemented at that axial end 13a or 13b of the stator core 2 in the specified winding scheme, at which the conductor sections La, Lb of the stator winding 14 are connected to one another in one piece or in the shape of a roof or bow, ie they are arranged on the so-called hairpin side of the stator 1 . In particular, all of the reversal conductor sections 17, 18 can be associated with the so-called "hairpin roof" side of the stator 1 lying closest. Thus, all required welding points between the conductor sections La, Lb of the stator winding 14 are concentrated on only one of the two axial front ends of the stator 1, namely assigned exclusively to the so-called twist or welding side of the stator 1.

The exemplary embodiments show possible variants, it being noted at this point that the invention is not limited to the specifically illustrated variants of the same, but rather that various combinations of the individual variants with one another are possible and these possible variations are based on the teaching on technical action the present invention is within the skill of a person skilled in the art working in this technical field.

The scope of protection is determined by the claims. However, the description and drawings should be used to interpret the claims. Linzei features or combinations of features from the different exemplary embodiments shown and described len can represent independent inventive solutions. The task on which the independent inventive solutions are based can be found in the description.

All information on value ranges in the present description is to be understood in such a way that it also includes any and all sub-ranges, e.g. the information 1 to 10 is to be understood as including all sub-ranges, starting from the lower limit 1 and the upper limit 10 are, ie all sections begin with a lower one Limit of 1 or greater and ending at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

Finally, for the sake of clarity, it should be pointed out that some elements are shown not to scale and/or enlarged and/or reduced in size in order to better understand the structure.

list of reference numbers

1 stator PW phase windings

2 stator core A-D current paths

3 central axis N, S magnetic pole sections

4 mounting grooves L layers

5 gap La, Lb conductor sections

6 addendum VBa, VBb electrical connection sections

7 slot base A-D current paths

8 Conductor Ai-Di Current Path Beginnings

9 insulation layer Ao-Do current path ends

10 circumferential direction Al-Dl input connections 11 axial direction A2-D2 output connections 12 radial direction a, 13b axial front ends

14 stator winding

15 wave winding

16 pair of shaped rods

17 Reversal s ladder section

18 Inversion s ladder section

19 connection section

20 transition ladder section 21 transition ladder section

Claims

P atentClaims

1. Stator (1) for an electrical machine, comprising

- an essentially hollow-cylindrical stator core (2) with a first and a second axial end (13a, 13b) and with several arranged distributed along a circumferential direction (10) of the stator core (2) and extending along a central axis (3) of the stator core (2 ) extending receiving grooves (4),

- Several electrical conductor sections (La, Lb) formed by shaped bars for each receiving groove (4), which conductor sections form a stator winding (14) through predetermined electrical connections, and which stator winding several in the radial direction (12) to the central axis (3) of the stator core immediately adjacent layers (L) of the conductor sections (La, Lb), and these conductor sections form predetermined electrical current paths (A, B, C, D) in the stator winding (14) through the predetermined electrical connections, and the stator in the circumferential direction ( 10) distributed several magnetic pole sections (N, S) defined, where

- the stator winding (14) comprises at least one phase winding (PW1, PW2, PW3), which at least one phase winding comprises at least two current paths (A, B, C, D),

- and each current path (A, B, C, D) has an input connection (Al-Dl), a current path start (Ai-Di), a current path end (Ao-Do) and an output connection (A2-D2) has, where

- At least one of the current paths (A, B, C, D) starts with its current path beginning (Ai-Di) starting from one of the radially outer layers (L8-L2) and then alternately in layers and in the circumferential direction (10) at least over along a partial section of the circumference of the stator up to the radially innermost layer (LI), with the current path at each of these changes of position from one of the magnetic pole sections (S or N) of the stator to a pole section (N or S) transitions, and the current path changes the layers (L) in a constantly constant radial direction by a layer jump width "one" until the radially innermost layer (LI) is reached, so that the current path has a helical and step-shaped course in relation to the Circumferential and radial direction (10, 12) of the stator, and wherein

- The direction of the electrical current path in the radially innermost layer (LI) in relation to the circumferential direction (10) of the stator core through a reversal conductor Section (17, 18) is reversed and then the electrical current path, starting from the radially innermost layer (LI), the layers (L) alternating in layers and running in the circumferential direction (10) at least over a partial section of the circular circumference of the stator and thereby in the radial direction offset by only one layer, again with a helical and step-like course with respect to the circumferential and radial direction (10, 12) of the stator back towards a radially more outward layer (L2-L8), wherein

- the current path has at least one spiral and step-shaped course in the radial direction (12) to the central axis (3) of the stator core and also at least one spiral and step-shaped course in the radial direction (12) away from the central axis (3) of the stator core, and where

- the current path ends with its current path end (Ao-Do) at a receiving groove (4) within a magnetic pole section (N or S), which magnetic pole section (N or S) in relation to the circumferential direction (10) of the stator a magnetic pole section (S or N), in which the current path begins with its current path beginning (Ai-Di), is arranged immediately adjacent, with these pole sections (N, S) immediately adjacent in the circumferential direction (10) having different poles,

- Or vice versa with regard to the helical and stepped course of at least one of the current paths (A, B, C, D) with regard to the radial direction (12) to the central axis (3) of the stator core (2), or vice versa constructed in Reference to the current path start (Ai-Di) and the current path end (Ao-Do) of at least one of the electrical current paths (A, B, C,

D).

2. Stator according to claim 1, characterized in that a running direction of the reversing conductor sections (17, 18) at the radially innermost layer (LI) and at the radially outermost layer (L8) with respect to the circumferential direction (10) of the stator in is chosen in such a way that the current path start (Ai-Di) and the current path end (Ao-Do) of all current paths (A, B, C, D) of all phase windings (PW1, PW2, PW3) within a common one Connection section (19) of the stator winding (14) come to rest, which extends over a maximum of two in the circumferential direction (10) of the stator immediately adjacent magnetic pole sections (N, S).

3. Stator according to claim 1 or 2, characterized in that a course Rich direction of the reversal conductor sections (17, 18) on the radially innermost layer (LI) and on the radially outermost position (L8) in relation to the circumferential direction (10) of the stator is selected in such a way that the current path start (Ai-Di) and the current path end (Ao-Do) of all current paths (A, B, C, D) of a dedicated phase winding (PW1, PW2, PW3) come to lie within the same layer (L) or come to lie in two immediately adjacent layers (L) in the radial direction (12).

4. Stator according to one of the preceding claims, characterized in that at least one of the current paths (A, B, C, D) or all current paths (A, B, C, D) on the one hand between the input terminal (Al-Dl) and the current path Beginning (Ai-Di) and on the other hand between the end of the current path (Ao-Do) and the output connection (A2-D2) each have transition conductor sections (20, 21), which transition conductor sections (20, 21) per current path ( A, B, C, D) in the circumferential direction (10) running towards each other in such a way that the input terminals (Al-Dl) and the output terminals (A2-D2) of these current paths (A, B, C, D) within a single magnetic pole section (N or S) of the stator.

5. Stator according to one of the preceding claims, characterized in that each of the at least two current paths (A-D) extends over more than 360° of the circumferential direction (10) of the Stator core (2) extends.

6. Stator according to one of the preceding claims, characterized in that each of the at least two current paths (AD) runs helically or spirally in a view of the two axial end faces (13a, 13b) of the stator core (2).

7. Stator according to one of the preceding claims, characterized in that in the reversal s-conductor sections (17, 18) a layer position of the current path (A-D) is retained unchanged, i.e. the reversal conductor sections (17,18) are each along the radially innermost or along the radially outermost layer (LI, L8).

8. Stator according to one of the preceding claims, characterized in that each current path (AD) has an even number of radial direction (12) and also in Circumferential direction (10) of the stator running current path sections, in particular comprises two, four, six or more such current path sections, and that between successive current path sections said reversal conductor sections (17, 18) are executed.

9. Stator according to one of the preceding claims, characterized in that the stator winding (14) comprises at least two electrical current paths (A-D) running in parallel and each current path start (Ai-Di) of these electrical current paths (A-D) in a first magnetic pole section (S or N) of the stator and each current path end (Ao-Do) of these electric current paths (A, B, C, D) is formed in a second magnetic pole portion (N or S) of the stator, which is related to the first magnetic pole portion ( S or N) in the circumferential direction (10) of the stator is immediately adjacent.

10. Stator according to one of the preceding claims, characterized in that the reversing conductor sections (17, 18) are formed exclusively in the radially innermost and finally in the radially outermost layer (LI, L8) of the stator winding (14).

11. Stator according to one of the preceding claims, characterized in that all the reversing conductor sections (17, 18) are carried out on that axial front end (13a or 13b) of the stator core (2) on which the conductor sections (La, Lb) of the stator wick are connected to one another in one piece and in the shape of a roof or bracket.

12. Stator according to one of the preceding claims, characterized in that conductor sections (La, Lb) electrically connected to one another form a wavy and also ring-like course of the electrical current paths (A, B, C, D), which wavy course is caused by alternating changes in the current paths (A, B, C, D) is defined between the first and the second axial front end (13a, 13b) of the stator core (2) and which ring-like course is defined by a simultaneous extension of the current paths (A, B, C, D) along the Circumferential direction (10) of the stator core (2) is defined.

13. Stator according to one of the preceding claims, characterized in that all input and output connections (Al-Dl, A2-D2) of the stator winding (14) are either at the first or at the second axial end (13a, 13b) of the stator core (2) are formed and are also arranged within a partial section of the circumference of the stator core (2) of a maximum of 90 °.

14. Stator according to one of the preceding claims, characterized in that the stator winding (14) has three or more phases and comprises three or more phase windings (PW1, PW2, PW3) each extending in the circumferential direction (10), and in that each phase winding has two or more electrical current paths (A, B, C, D) running in parallel.

15. Electrical machine comprising a stator and a rotor, characterized in that the stator (1) is formed out according to one or more of the preceding claims.