DE102024101655A1 - STATOR FOR AN ELECTRICAL MACHINE - Google Patents

Abstract

A stator (50) for an electrical machine is provided, wherein the stator (50) comprises a stator housing (20) and a stator laminated core (1) which is accommodated in the stator housing (20). The stator laminated core (1) has a hollow cylindrical base body (2) and a plurality of webs (5) which are formed on an outer surface (4) of the base body (1) at a distance from one another in the circumferential direction of the stator laminated core (1) and each extend in an axial direction of the stator laminated core (1) along the outer surface (4). The plurality of webs (5) each protrude in the direction of the stator housing (20) and bear against the stator housing (20), wherein grooves (6) formed between the plurality of webs (5) are closed at least on one side by the stator housing (20) and form receptacles for coil arrangements (10).

Description

The present disclosure relates to a stator for an electric machine, an electric machine comprising the stator, and/or a motor vehicle comprising the electric machine.

Electrical machines, which can be used in motor vehicles, for example, as traction machines, each have a rotor and a stator surrounding the rotor. Applying electrical current to the windings or coils of the stator and/or the rotor creates a magnetic interaction between the stator and the rotor, providing mechanical energy that can be tapped via the rotation of the rotor and used, for example, to drive the electrically powered motor vehicle or another machine in the motor vehicle.

Currently used stator windings are coils arranged in stator slots, which are usually located along the inner diameter of a stator. There are various winding designs for implementing coils or coil arrangements, e.g., wave windings in hairpin or I-pin designs, or endless windings.

The continuous winding design has the major advantage of being easier to manufacture and requiring only a few weld points. However, since these must be inserted radially into the stator from the inside, the stator slots must be designed accordingly large, which results in lower performance and efficiency of the corresponding electrical machine. The hairpin design has the major disadvantage of requiring numerous weld points, which places high quality demands on the process and requires a large amount of production time and space. However, with a hairpin design, the stator slots can be designed as small as possible.

DE 10 2008 025 512 A1 describes a method for assembling the stator of an electrical machine, wherein a first star-shaped bearing shield is positioned on a first end face of a stator laminated core having a star-shaped cross-section. A second star-shaped bearing shield is positioned on the second end face of the stator laminated core. Wound winding supports are then placed radially onto the star-shaped stator laminated core in such a way that the teeth of the stator laminated core and the radial extensions of the star-shaped bearing shields are each passed through a central recess of one of the wound winding supports. A hollow cylindrical yoke is then pushed axially onto the stator laminated core provided with wound winding supports.

US 2008/0191576 A1 describes a stator for a motor comprising a stator core having an annular yoke and a magnetic pole generating member disposed in the annular yoke, and a plurality of excitation winding portions distributed on the magnetic pole generating member, wherein the yoke and the magnetic pole generating member are each formed by laminating a plurality of magnetic sheets.

DE 10 2021 002 941 A1 describes a pole element for providing an electrical pole of an axial flux machine, with two opposing pole shoes, between which a winding to be carried by the pole element can be arranged, wherein the pole element has a base body formed from a plurality of layers arranged on top of one another and made of a metallic material, which is provided on the outer circumference by injection molding, casting, printing or sintering with a material from which the pole shoes formed integrally with one another are formed.

Against the background of this prior art, the object of the present disclosure is to provide a device and/or a method which are each suitable for enriching the prior art.

The problem is solved by the features of the independent claims. The subordinate claims and the dependent claims each contain optional developments of the disclosure.

The task is then solved by a stator for an electrical machine.

The stator comprises a stator housing and a stator lamination stack which is housed in the stator housing.

The stator laminated core comprises a hollow cylindrical base body (e.g., completely closed in the circumferential direction) and a plurality of webs. The webs are formed on an outer surface of the base body, spaced apart from one another in the circumferential direction of the stator laminated core, and each extend in an axial direction of the stator laminated core along the outer surface.

The multiple webs each protrude in the direction of the stator housing and are located on the stator housing. Slots formed between the plurality of webs are closed at least on one side by the stator housing and form receptacles for coil assemblies (or receptacles for receiving coil assemblies).

The stator described above offers a number of advantages. For example, the stator can be produced and manufactured more efficiently than conventional stators because it features receptacles for coil assemblies that allow the coil assemblies to be joined radially from the outside, rather than from the inside, as has been the case up to now. In addition to easier joining, the slots can be smaller than in conventional stators, allowing for more efficient use of the installation space, which can, for example, impact the performance and efficiency of the corresponding electrical machine.

Furthermore, by making the slots smaller, the resource requirements for (electrical) sheet metal can be advantageously reduced. For example, the webs can be extended outward only as far as necessary to accommodate the coil arrangements in the slots. This can reduce the material required for the stator core, which in turn can lead to cost, weight, and environmental advantages over conventional stators.

Possible further developments of the stator described above are explained in detail below.

The plurality of webs can protrude outward and/or radially in the radial direction of the stator (and/or the stator laminated core). It is conceivable that the plurality of webs each have a basic shape (or cross-sectional shape) that widens outward and/or is wedge-shaped in the radial direction of the stator (and/or the stator laminated core).

The plurality of webs may be of identical design and/or have at least an identical basic shape (or cross-sectional shape), length, width and/or height.

Each free end (and/or each surface facing away from the outer surface of the base body) of the plurality of webs can rest (and optionally be fixed) on the stator housing (e.g., an inner surface of the stator housing). The plurality of webs can be fixed to the stator housing.

The stator may include a plurality of coil assemblies, each of which is received (and/or joined) in one of the receptacles. The plurality of coil assemblies may each include a metal core (e.g., an iron core) and a coil wound around the metal core.

The plurality of coil arrangements can each be designed as a pre-assembled module and/or the respective coil can be (or comprise) an endless winding.

A respective width and/or height of the plurality of coil assemblies may extend in the radial direction of the stator (and/or the stator core). The plurality of coil assemblies may each be aligned in the radial direction of the stator (and/or the stator core).

The metal core can be in direct contact with the stator core and/or two of the multiple webs. The metal core can be clamped and/or pressed between two of the multiple webs.

The plurality of webs may each have a minimum height such that (in each case) the metal core of an adjacent coil arrangement of the plurality of coil arrangements (i.e., a coil arrangement arranged adjacent to the respective web of the plurality of webs) is in direct contact with the respective web of the plurality of webs (and/or with the stator core) along an entire width and/or height of the metal core.

Within the receptacles, gaps (or cavities) can be formed between the stator housing and the multiple coil assemblies, and between the base body and the multiple coil assemblies. The gaps (or cavities) can be provided as coolant channels (e.g., for direct cooling of the coils).

The receptacles can be formed in sections by recesses in the stator housing. This can advantageously lead to a further reduction in installation space.

An inner surface of the base body can be (e.g., completely) contourless and/or smooth. This can advantageously reduce air friction losses between the rotor and the stator, with this advantage becoming increasingly pronounced at higher rotor speeds.

The stator housing can be designed as a hollow cylinder, at least in sections. The stator housing and the stator core can be arranged coaxially to one another, at least in sections.

The stator housing may have an inner diameter and/or an inner surface for torque support of the stator.

The above description can be summarized in other words and in a possible more concrete embodiment of the disclosure as described below, whereby the following description is not to be interpreted as limiting the disclosure.

According to the present disclosure, an endless winding with an integrated iron core can be joined radially from the outside while simultaneously keeping the resource requirements for electrical steel sheet as low as possible. For this purpose, the individual coils (with iron core) can be effectively formed in a previous process step, e.g., in the form of a "sandwich" or "mat."

The stator laminated core can have a closed, smooth and cylindrical inner surface and radial webs with grooves protruding towards the outer surface. The coil assemblies can be inserted or placed in these grooves. The stator laminated core can be connected to the iron core of the coils via direct contact between these two partners, e.g. via a slight press fit. In order to reduce the resource contribution of the stator laminated core, the outer diameter of the webs can be extended only as far outwards as necessary, i.e. up to the radial height of the iron core of the coil assemblies. This can significantly reduce the material required for the stator laminated core. This can have cost, weight and environmental ( _CO2e ) advantages compared to the standard designs mentioned above. The concept thus enables very simple, pure separation of materials.

The housing that houses the stator or stator core can have an appropriate inner diameter for torque support surfaces. Recesses can be machined into the housing to ensure sufficient space for the coil arrangement. This not only reduces the installation space, but also allows the resulting gaps between the coils with iron cores, the stator core, and the housing wall to be used for direct winding cooling. This means that a cooling medium can flow directly along the coils and dissipate heat, thereby significantly increasing the performance of the electrical machine. Furthermore, the closed inner diameter of the stator ensures that no cooling medium can enter the air gap between the rotor and stator, which could cause high friction losses. This smooth inner diameter can also have the advantage of minimizing air friction losses between the rotor and stator. These machines are therefore ideal for very high-speed electrical machines, for example.

Furthermore, an electric machine (for a motor vehicle) is provided which comprises the stator described above.

The electric machine may comprise a rotor, wherein the stator may surround the rotor at least circumferentially or in the circumferential direction (of the rotor).

The rotor may have a rotor shaft. The rotor may have a rotor core that may surround the rotor shaft. The rotor shaft may be received in a central opening of the rotor core.

What was described above with reference to the stator also applies analogously to the electrical machine and vice versa.

Furthermore, a motor vehicle is provided which comprises the electric machine described above.

The motor vehicle may be an electrically powered motor vehicle. The electric machine may be designed as a traction motor or traction machine of the motor vehicle.

The motor vehicle may comprise an electrical source, e.g., a traction battery, for supplying the plurality of coil assemblies of the stator (or the coils of the plurality of coil assemblies) with electrical energy and/or with an alternating current via at least one inverter.

The motor vehicle may be a passenger car, in particular an automobile, or a commercial vehicle, such as a truck.

What has been described above with reference to the stator and the electric machine also applies analogously to the motor vehicle and vice versa.

• 1 zeigt schematisch eine Schrägansicht eines Statorblechpakets eines offenbarungsgemäßen Stators,
• 2 zeigt schematisch eine Schrägansicht des Statorblechpakets mit mehreren Spulenanordnungen,
• 3 zeigt schematisch eine Schrägansicht des Stators, und
• 4 zeigt schematisch einen vergrößerten Ausschnitt des Stators in einer Querschnittsansicht.

Below is an optional embodiment with reference to 1 to 4 described.

• 1 shows schematically an oblique view of a stator laminated core of a stator according to the disclosure,
• 2 shows a schematic oblique view of the stator core with several coil arrangements,
• 3 shows schematically an oblique view of the stator, and
• 4 shows schematically an enlarged section of the stator in a cross-sectional view.

1 shows only schematically the stator laminated core 1, which has a hollow cylindrical base body 2 and several webs 5.

The plurality of webs 5 are formed spaced apart from one another in the circumferential direction of the stator laminated core 1 on an outer surface 4 of the base body 1 and each extend in an axial direction of the stator laminated core 1 along the outer surface 4.

Grooves 6 are formed between the plurality of webs 5 (or through the webs 5) and form receptacles for coil arrangements.

An inner surface 3 of the base body 2 can be contourless and/or smooth.

2 shows the stator core 1 from 1 and further coil assemblies 10, each of which is received or filled in one of the receptacles formed by the slots 6. In other words, the number of coil assemblies 10 corresponds to the number of slots 6, so that each slot 6 is filled by a coil assembly 10.

3 shows the stator 50, which has a stator housing 20 and the 2 shown arrangement comprising the stator laminated core 1 and the coil assemblies 10, wherein the stator laminated core 1 is accommodated in the stator housing 20. It is conceivable that the stator housing 20 is designed, for example, as part of a housing structure of the stator 50, wherein the stator housing 20 can be provided for receiving the stator laminated core 1.

The plurality of webs 5 each protrude (e.g. outwards in the radial direction of the stator 50) in the direction of the stator housing 20 and bear against the stator housing 20, wherein the slots 6 are closed at least on one side by the stator housing 20 and form the receptacles for the coil arrangements 10. As in 3 As shown, the receptacles can be formed in sections by recesses 21 in the stator housing 20.

It is conceivable that the 1 to 3 represent an assembly sequence (ie, an assembly method) of the stator 50. First, the stator core 1 is provided ( 1 ), then the plurality of coil assemblies 10 are inserted into the receptacles ( 2 ), and finally, the stator core 1 with the multiple coil arrangements 10 is inserted into the stator housing 20, so that the stator housing 20 surrounds the stator core on its circumference ( 3 ).

In 4 is an enlarged view of a section of the stator 50, in which it can be seen that the plurality of coil assemblies 10 can each have a metal core 11, e.g., an iron core or a separate laminated core, and a coil 12 wound around the metal core 11.

The multiple coil arrangements 10 can each be configured as a preassembled module. The respective coil 12 can, for example, be a continuous winding.

The respective metal core 11 can be in direct contact with the stator core 1 and/or two of the plurality of webs 5. For example, the metal core 11 and thus the respective coil arrangement 10 can be clamped between two webs 5 and/or pressed, e.g., by means of a press fit.

The plurality of webs 5 may each have a minimum height such that the metal core 11 of an adjacent coil arrangement 10 (i.e., a coil arrangement 10 arranged adjacent to the respective web 5 of the plurality of webs 5) is in direct contact with the respective web 5 along an entire width and/or height of the metal core 11.

Within the receptacles, gaps 30 (or cavities) can be formed between the stator housing 20 and the plurality of coil assemblies 10, and gaps 31 can be formed between the base body 2 and the plurality of coil assemblies 10, wherein the gaps 30 can be formed, for example, within the recesses 21 of the stator housing 20. It is conceivable to provide these gaps 30, 31 as coolant channels, i.e., to pass coolant through the gaps 30, 31 in order to directly cool the plurality of coil assemblies 10 or the coils 12 during operation.

List of reference symbols

1

Stator lamination stack

2

Basic body

3

Inner surface of the base body

4

Outer surface of the base body

5

Footbridges

6

grooves

10

Coil arrangements

11

Metal cores

12

Wash

20

Stator housing

21

Deepenings

30, 31

Gaps

50

stator

QUOTES CONTAINED IN THE DESCRIPTION

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

Cited patent literature

• DE 10 2008 025 512 A1 [0005]
• US 2008/0191576 A1 [0006]
• DE 10 2021 002 941 A1 [0007]

Claims (10)

Stator (50) for an electrical machine, wherein the stator (50) comprises: - a stator housing (20), and - a stator laminated core (1) which is received in the stator housing (20), wherein the stator laminated core (1) has: - a hollow cylindrical base body (2); and - a plurality of webs (5) which are formed at a distance from one another in the circumferential direction of the stator laminated core (1) on an outer surface (4) of the base body (1) and each extend in an axial direction of the stator laminated core (1) along the outer surface (4), characterized in that the plurality of webs (5) each protrude in the direction of the stator housing (20) and bear against the stator housing (20), wherein grooves (6) which are formed between the plurality of webs (5) are closed at least on one side by the stator housing (20) and form receptacles for coil arrangements (10). Stator (50) after Claim 1 , characterized in that the stator (50) comprises: - a plurality of coil assemblies (10), each of which is received in one of the receptacles, the plurality of coil assemblies (10) each having a metal core (11) and a coil (12) wound around the metal core (11). Stator (50) after Claim 2 , characterized in that the plurality of coil arrangements (10) are each designed as a pre-assembled module and the respective coil (12) is an endless winding. Stator (50) after Claim 2 or 3 , characterized in that the metal core (11) is in direct contact with the stator laminated core (1) and/or two of the plurality of webs (5). Stator (50) according to one of the Claims 2 until 4 , characterized in that the plurality of webs (5) each have a minimum height, so that the metal core (11) of an adjacent coil arrangement (10) of the plurality of coil arrangements (10) is in direct contact with the respective web (5) of the plurality of webs (5) along an entire width and/or height of the metal core (11). Stator (50) according to one of the Claims 2 until 5 , characterized in that gaps (30, 31) are formed within the receptacles between the stator housing (20) and the plurality of coil arrangements (10) and between the base body (2) and the plurality of coil arrangements (10), wherein the gaps (30, 31) are provided as coolant channels. Stator (50) according to one of the Claims 1 until 6 , characterized in that the receptacles are formed in sections by recesses (21) in the stator housing (20). Stator (50) according to one of the Claims 1 until 7 , characterized in that an inner surface (3) of the base body (2) is contourless and/or smooth. Electrical machine, characterized in that the electrical machine has the stator (50) according to one of the Claims 1 until 8 includes. Motor vehicle, characterized in that the motor vehicle has the electrical machine according to Claim 9 includes.