WO2017194264A1

WO2017194264A1 - Stator for an electrical machine having an interconnection device for stator coils, and electrical machine having a stator of this kind

Info

Publication number: WO2017194264A1
Application number: PCT/EP2017/058912
Authority: WO
Inventors: Martin Geiger; Matthias Weidner
Original assignee: Zf Friedrichshafen Ag
Priority date: 2016-05-12
Filing date: 2017-04-13
Publication date: 2017-11-16
Also published as: DE102016208150A1

Abstract

A stator (16) for an electrical machine (10) is described, having an annular laminated stator core (26) which is secured to a stator carrier (24) and on which a number of stator coils (36) with coil ends (36a, b), which axially protrude from the laminated stator core (26), are arranged. The stator also comprises an interconnection device (38) for the stator coils (36), which interconnection device is arranged on an end face of the laminated stator core (26) and has a plurality of connecting conductors (52, 54, 56) which are arranged coaxially with respect to one another, are mutually insulated and are arranged axially adjacent to the stator coils (36). The connecting conductors (52-56) comprise coil connection regions (52a-56a) for the coil ends (36a, b) and power connection regions (52c-56c) for supplying power to the electrical machine (10). It is proposed to arrange the interconnection device (38) outside the stator coils (36) and therefore on the stator carrier (24) and/or to arrange and axially support the interconnection device on a component which is permanently connected to the stator carrier.

Description

Stator of an electrical machine with an interconnecting device for stator coils and electrical machine with such a stator

The present invention relates to a stator of an electric machine with a wiring arrangement for stator coils according to the preamble of claim 1.

A generic stator is known from EP 1 184 957 B1, in which an interconnecting device with a plurality of axially staggered concentric connection conductors is arranged axially adjacent to a plurality of stator coils fixed to the stator in a ring-shaped manner and attached to the winding bodies of these stator coils. The coil ends occur axially from the coils and are connected to terminal areas, which in each case protrude from the connecting conductors to a radially outer peripheral region of the interconnection means or are led out.

Due to the direct definition of the interconnection arrangement on the stator coils, in particular on their winding bodies, an occurring contacting force is transmitted directly to the connection region and to the coils when the coil ends are connected or contacted with the connection conductors. As a result, the coils can be loaded undesirably and the entire arrangement can be deformed, as a result of which permanent damage to the circuitry and the coils can already be produced during the production of the stator.

The object of the present invention is to provide a stator of an electrical machine of the type mentioned at the outset and an electrical machine with an assembly-safe and easy-to-install interconnecting device for the stator coils.

This object is achieved by a stator with features of claim 1 and further by an electric machine having the features of claim 10. Advantageous embodiments and further developments of the invention are the dependent claims and the following description can be removed.

It is thus proposed according to a first aspect, a stator of an electric machine with an annular stator lamination, which is fixed to a stator and on which a number of stator coils is arranged and wherein the coil ends project axially from the stator lamination. The stator comprises, on the stator side, a stator coil interconnection device which has a plurality of mutually coaxially arranged and mutually insulated connection conductors arranged axially adjacent to the stator coils, and wherein the connection conductors comprise coil terminal areas for the coil ends and power terminal areas for powering the electrical machine.

The proposed stator is characterized in that the interconnection device is arranged outside of the stator coils and thus on the stator carrier and / or on a component fixedly connected thereto and is axially supported. In this way, forces acting on the interconnection device, in particular contacting forces, can be kept away from the coils themselves and be dissipated onto the stator carrier and / or other components.

Advantageously, the coil connection areas may be formed on the front side of the interconnection device, whereby a sufficient space for engagement of an assembly tool is given. The coil ends can thereby be connected in particular under the action of an axial contacting force directed toward the stator lamination stack.

With still further advantage, the interconnection device for arranging the connection conductors can have a plastic carrier element and a reinforcing metallic reinforcing element reinforcing it, in particular a sheet metal element which extends in the radial direction over the coil connection regions of the connection conductors to receive contacting forces. The reinforcing element and the plastic carrier element can proceed, for example, as a common hybrid component and be produced, for example, by a casting process. The reinforcing element can thus be axially surrounded on both sides by plastic. Alternatively, the reinforcing element and the plastic carrier element can also be connected to one another by means of a non-detachable connection, in particular a rivet connection or the like. Still further, the reinforcing element can be arranged axially between the stator coils and the connecting conductors.

The fixing or the fastening and the axial support of the interconnection device on the stator carrier or on a component permanently connected thereto can advantageously be effected by the reinforcing element and in particular by means of an axial connecting section provided on the reinforcing element.

In a further embodiment of the stator, an axial gap can be formed between the interconnection device and the coils, which permits the passage of a coolant, in particular an air flow or a cooling fluid, which is in heat transfer with the coils in the circumferential direction and / or in the radial direction. In addition, this creates a movement scope for receiving a deformation when contacting the interconnecting the coil ends.

According to a manufacturing technology favorable variant, both the reinforcing element and the stator can be designed as sheet metal parts and connected to each other by means of a reliable non-detachable connection, in particular by means of a riveted joint. Such a stator is a robust prefabricated unit, which can then be used and mounted in a housing of the electrical machine, for example in a transmission housing of a motor vehicle. The stator carrier may preferably be formed as a cylindrical sheet-metal element and the reinforcing element as a substantially disc-shaped body, of the latter for mutual connection of the parts in regions on the inner or Au ßenumfang several notches as a connection training areas are formed. The remaining gaps can form connection areas for connection to the plastic carrier element.

In the case of the proposed stator, the coils can advantageously be fixed on the stator lamination stack by means of winding bodies, wherein in particular a winding body has a winding region which is formed by a winding carrier and two limbs delimiting the winding region in the axial direction and connected to the winding carrier. To minimize operational vibrations or displacements of the coil ends relative to the interconnection device, they can be led out to the interconnection device with further advantage at a leg which is spatially radially adjacent to or adjacent to the connection section of the reinforcement element.

The present invention further relates to an electric machine having a rotor and a stator, the stator having at least one feature as explained above.

The invention will be explained by way of example with reference to an embodiment shown in the figures.

Show it:

Figure 1 is a schematic representation of an electrical machine with a stator and a wiring device.

FIG. 2 shows a perspective view of the stator of FIG. 1 with the interconnection device; FIG.

Fig. 3 is an end view of the stator of Fig. 2;

FIG. 4a shows an axial section of the stator of FIG. 3 in the region of coil ends entering the interconnection device; FIG.

4b shows a further axial section of the stator of FIG. 3 in a connecting region of a reinforcing element with a plastic carrier element of the interconnecting device. Identical objects, functional units or comparable components are denoted by the same reference numerals across the figures. Further, summary reference numbers are used for components and objects that occur multiple times in one embodiment or in one representation, but are described together in terms of one or more features. Components or objects which are described by the same or by the same reference numerals may be the same, but possibly also different, in terms of individual, several or all features, for example their dimensions, unless otherwise explicitly or implicitly stated in the description. In order to avoid repetition, a multiple description of identical objects, functional units or comparable components in various exemplary embodiments is dispensed with and only differences of the exemplary embodiments are described in this regard.

1 schematically shows an electric machine 10, more precisely a permanent magnet synchronous machine of internal rotor type, with a rotor 14 rotatable about a rotor shaft 12 with a rotation axis A and with a stator 16 surrounding it radially outside. The rotor 14 comprises a cup-shaped rotor carrier 18, on the cylindrical outer peripheral surface of a laminated laminated rotor core 20 is arranged, which carries a plurality of circumferentially spaced-apart permanent magnets 22.

The stator 16 comprises an annular stator carrier 24 which is present here as a cylindrical sheet-metal body, in the central recess of which an annular stator lamination stack 26 likewise formed from laminations is arranged. The axis of rotation A thus forms at the same time the central axis A of the stator. The stator support 24 may, for example, constitute an external or an intermediate housing of the electric machine 10 or be provided for installation in such. A torque acting on the stator 16 is absorbed via a form-locking connection of the stator carrier 24 with the respective connection partner, for which purpose a plurality of recesses 24b distributed on the circumference are provided on the stator carrier for receiving engagement sections of the connection partner not shown here. The laminated stator core 26 comprises an annular stator yoke 30, which bears against the stator carrier 24 and has teeth 32 projecting radially inwards from the latter and which is equipped with stator coils 36 to form a stator winding. These stator coils 36 are wound with the help of two, consisting of a heat-resistant plastic insulating or bobbins 40, 42 of a copper wire around the teeth 32 and are secured against slipping there. The bobbins 40, 42 each include a front side on the laminated core 26 adjacent base region or winding support 40a; 42a and two of them approximately at right angles and on the stator 16 axially projecting leg 40b, c; 42b, c, which define a winding region 43 in the radial direction.

The coils 36 are electrically associated with individual strands, for which purpose the coil ends 36a, b are interconnected in a predetermined manner by means of an interconnecting device 38 shown only schematically as a block in FIG. 1.

As can be seen from the following FIGS. 2 to 4, the interconnecting device 38 comprises for this purpose a carrier element 58 made of plastic, in which a plurality of mutually insulated connecting conductors 52, 54, 56 are arranged. The connecting conductors 52, 54, 56 have for connection to the coil ends 36a, b at the end remote from the stator 16 end circumferentially spaced coil connection areas 521; 541, 561 on. The interconnecting device 38 is spatially axially positioned in the embodiment described here outside the stator coils 36 and fixed to the stator 24 and there also axially supported. Alternatively or together with this, a fixing and support can also take place on a component fixedly connected to the stator carrier 24, for example on the stator lamination stack 26.

With reference to FIG. 1, the interconnection device 38 is connected via power connection regions 52c, 54c, 56c of the connection conductors 52, 54 by means of connection conductors 52d, 54d, 56d to power electronics 39a and control electronics 39b to an electrical energy source 39c, which is used to operate the electric machine 10 can apply a variable phase current and amplitude to the winding. In the present case, the connecting conductors 52, 54, 56 are made of a copper semifinished product, in particular of a copper plate or a copper sheet by means of a stamping process as a ring strip or annular bands. The ring strips are arranged on the stator 16 coaxial with the central axis A and stacked radially to one another.

The connecting conductors 52, 54, 56 are in the illustrated embodiment, except for the coil terminal portions 521, 541; 561 approximately completely poured into the plastic matrix of the support member 58. The coil terminal portions 521, 541; 561 are formed as axially highlighted regions on the front side of the annular disk-shaped connecting conductors 52, 54, 56 and thus stand out of the plastic matrix. Correspondingly, corresponding to the circumferential positions of the coil connection regions 521, 541; 561 radially adjacent and before their interconnection initially axially aligned coil ends 36a, b from the coils 36, which at the interconnection device 38 radially in the direction of the coil connection regions 521, 541; 561 are bent and cross these for interconnection or lie there. Furthermore, the coil connection regions 521, 541, 561 of all connection conductors 52, 54, 56 are arranged essentially within a common radial plane, that is to say at the same axial height.

In the illustrated embodiments, the interconnection of the coil ends 36a, b for the realization of a delta connection with three connecting conductors 52, 54, 56 is shown. Furthermore, in each case two adjacent coil ends 36a, b of two circumferentially adjacent coils 36 are each connected to a coil connection region 521, 541, 561 of one of the connection conductors 52, 54, 56.

The contacting of the coil ends 36a, b with the connecting conductors 52, 54, 56 takes place cohesively, in particular by brazing, wherein per contact a mainly in the axial direction of the coils directed force of about 500N acts on the coil connection areas. To support this Kontaktierkraft and manufacturing reasons, the plastic support member 58 with a ring-shaped metallic reinforcing element 60, in particular a Sheet metal element formed, which extends in the radial direction over the coil connection regions 52a-56a of the connection conductors 52-56.

The reinforcing element 60 and the plastic carrier element 58 are non-detachably connected to one another in the radially outer region of the plastic carrier element 58 by means of a plurality of rivet connections 62. To fix the interconnecting device 38 to the sheet-shaped stator carrier 24, a plurality of axial connecting sections 60a, in particular axial notches with radially projecting end sections 60b, are provided in the radially outer region of the sheet-shaped reinforcing element 60. These end portions 60b are also connected by means of a non-detachable connection 64, in particular by means of a plurality of rivet connections with a provided on the stator 24 radial collar 24a.

It can also be seen in FIGS. 4a, b that the reinforcing element 60 is arranged axially between the stator coils 36 and the connecting conductors 52-56 and that an axial gap 66, in particular an annular space, is formed between the interconnecting device 38 and the coils 36 For cooling the winding areas 43, a cooling medium can flow. It is also visible that the coil ends 36 a, b are led out to the interconnection device 38 at the radially outer leg 40 of the winding body 40 that is spatially radially adjacent to the connecting section 60 a. For this purpose, in the reinforcing element 60 and in the plastic carrier element 58 passages 60c; 58a trained.

To protect the mutual contact points of the coil connection regions and the coil ends, the stator of the electrical machine can be provided with a coating, for example a powder coating, a coating or with a silicone coating, at least in the region of the interconnection device.

The subject matter of the invention is not limited to stators of permanently excited electrical machines, but can be transferred beyond the illustrative embodiment to other types of electrical machines or their stators. Reference number electrical machine

rotor shaft

rotor

stator

rotorarm

Laminated core

magnet

stator

a radial collar

b recess

stator lamination

stator yoke

tooth

stator

a, b coil end

Verschaltungsseinrichtunga power electronics

b control electronics

c energy source

, 42 bobbins

a, 42a winding carrier

b, c thighs

winding area

, 54, 56 connecting conductors

a coil connection area

Power connection area Power connection area Power connection area d connecting conductor connecting conductor connecting conductor

Kunststoffträgerelementa passage

Reinforcement element a connecting portion b end portion

c passage

, 64 connection

axial gap

axis of rotation

Claims

claims

1. Stator (16) of an electrical machine (10) with

- An annular stator lamination (26) which is fixed to a stator (24) and to which a number of stator coils (36) with coil ends (36 a, b) is arranged, which axially projecting from the stator lamination (26) and with

- An interconnected on the stator laminated core (26) Verschaltungseinrich- device (38) for the stator coils (36), wherein

- The interconnection device (38) has a plurality of coaxially arranged and mutually insulated connection conductors (52, 54, 56), which are arranged axially adjacent to the stator coils (36) and wherein

the connection conductors (52-56) comprise coil connection regions (52a-56a) for the coil ends (36a, b) and power connection regions (52c-56c) for supplying power to the electrical machine (10),

characterized in that the interconnection device (38) is arranged outside the stator coils (36) and thus on the stator carrier (24) and / or on a component fixedly connected thereto and is axially supported.

2. Stator according to claim 1, characterized in that the coil connection regions (52 a - 56 a) are formed on the front side of the interconnection device (38).

3. Stator according to claim 1 or 2, characterized in that the interconnecting device (38) for the arrangement of the connecting conductors (52-56) has a plastic carrier element (58) and a reinforcing metallic reinforcing element (60), in particular a sheet metal element comprises, which extending in the radial direction over the coil terminal portions (52a-56a) of the connecting conductors (52-56).

4. Stator according to claim 3, characterized in that the reinforcing element (60) and the plastic carrier element (58) are produced as a common hybrid component, in particular by a casting method, or that said parts Le (58, 60) by means of a permanent connection (62), in particular a riveted joint, are interconnected.

5. Stator according to claim 3 or 4, characterized in that the reinforcing element (60) axially between the stator coils (36) and the connecting conductors (52 - 56) is arranged.

6. Stator according to one of claims 3-5, characterized in that the interconnecting device (38) by means of an on the reinforcing element (60) provided for axial connecting portion on the stator (24) or on a permanently connected thereto and is fixed supported there axially.

7. Stator according to one of claims 1 -6, characterized in that between the interconnecting device (38) and the coils (36) an axial gap (66) is formed.

8. Stator according to one of claims 3-7, characterized in that the reinforcing element (38 and the stator (24) are designed as sheet metal parts and by means of a non-detachable connection (64), in particular by means of a rivet connection are interconnected.

9. Stator according to one of claims 1 -8, characterized in that the coils (36) by means of winding bodies (40) on the stator lamination (26) are fixed, wherein a winding body (40) has a winding region (43) by a Winding carrier (40 a) and two the winding region (43) in the axial direction limiting and with the winding support (40 a) connected leg (40 b, c) is formed and wherein the coil ends (36 a, b) at a spatially radially to the Connecting portion adjacent or nearest leg (40b, c) to the interconnection device (38) are led out.

10. Electrical machine (10) with a rotor (14) and with a stator (16), wherein the stator (16) according to at least one of claims 1-9 is executed.