Electrical machine, in particular for a vehicle with a cooling channel for cooling stator windings

Patent metadata

Field	Value
Publication number	US-12206306-B2
Application number	US-201916686206-A
Country	US
Kind code	B2
Filing date	Nov 17, 2019
Priority date	Nov 19, 2018
Publication date	Jan 21, 2025
Grant date	Jan 21, 2025

Abstract

An electrical machine may include a rotor rotatable about an axis of rotation, by way of which an axial direction of the electrical machine may be defined, a stator having electrically conductive stator windings, and at least one cooling channel through which a coolant may be flowable for cooling the stator windings. The stator may have stator teeth extending along the axial direction, arranged spaced apart from another along a circumferential direction of the rotor, and bearing the stator windings. The at least one cooling channel and at least one stator winding may be arranged in at least one intermediate space formed between two stator teeth adjacent in the circumferential direction. A plastic for transferring heat from the at least one stator winding to the at least one cooling channel may be arranged in the at least one intermediate space.

First claim

The invention claimed is:

1. An electrical machine comprising:
a rotor that is rotatable about an axis of rotation, by way of which an axial direction of the electrical machine is defined, and a stator that has electrically conductive stator windings; and
at least one cooling channel through which a coolant is flowable for cooling the stator windings;
wherein the stator has stator teeth that extend along the axial direction, are arranged spaced apart from one another along a circumferential direction of the rotor, and bear the stator windings;
wherein the at least one cooling channel and at least one stator winding are arranged in at least one intermediate space that is formed between two stator teeth adjacent to each other in the circumferential direction;
wherein a first plastic for transferring heat from the at least one stator winding to the at least one cooling channel is arranged on surface sections of the two adjacent stator teeth delimiting the intermediate space;
wherein a second plastic forms at least one phase insulation arranged in the intermediate space and that divides the intermediate space into a radially inner subspace and a radially outer subspace and forms filler portions;
wherein a third plastic surrounds an entire perimeter of the at least one cooling channel in a cross section perpendicular to the axial direction and is in contact with at least one of the first plastic and the second plastic;
wherein the at least one phase insulation formed by the second plastic is arranged between a plurality of first conductor elements of the stator winding disposed in the radially inner subspace and a plurality of second conductor elements of the stator winding disposed in the radially outer subspace;
wherein the filler portions of the second plastic are disposed between each of adjacent first conductor elements of the plurality of first conductor elements and each of adjacent second conductor elements of the plurality of second conductor elements;
wherein the intermediate space including the radially inner subspace and the radially outer subspace is provided substantially without gaps via the second plastic so as to be free from air pockets; and
wherein the at least one phase insulation has a radial thickness greater than that of the filler portions.

2. The electrical machine according to claim 1 , wherein:
the stator comprises a stator body from which the stator teeth protrude radially inwardly; and
the first plastic is arranged on a surface section of the stator body that radially outwardly delimits the intermediate space.

3. The electrical machine according to claim 1 , wherein the first plastic is arranged on surface sections of at least one of (i) the two adjacent stator teeth and (ii) a stator body from which the stator teeth protrude radially inward, to form an electrically insulating layer that covers the surface sections.

4. The electrical machine according to claim 1 , wherein the at least one cooling channel is arranged in a region of a radially inner end section or a radially outer end section of the intermediate space.

5. The electrical machine according to claim 1 , wherein the at least one phase insulation formed by the second plastic is arranged in the intermediate space and that divides the intermediate space into the radially inner subspace and the radially outer subspace, such that first conductor elements of the stator winding that form a first phase winding are able to be arranged in the radially inner subspace, and second conductor elements of the stator winding that form a second phase winding that is electrically insulated from the first phase winding are able to be arranged in the radially outer subspace.

6. The electrical machine according to claim 5 , wherein the at least one phase insulation extends along the circumferential direction and connects two insulating layers made from the first plastic and arranged on the adjacent stator teeth to one another.

7. The electrical machine according to claim 5 , wherein:
the plurality of first conductor elements are arranged in the radially inner subspace and electrically connected to one another in order to connect to a common first phase of an electric current source; and
the plurality of second conductor elements are arranged in the radially outer subspace and electrically connected to one another in order to connect to a common second phase of the electric current source.

8. The electrical machine according to claim 7 , wherein at least one of the plurality of first conductor elements and the plurality of second conductor elements are individually surrounded by the second plastic, which is electrically insulating and thermally conductive, in a cross section perpendicular to the axial direction.

9. The electrical machine according to claim 7 , wherein at least one of the plurality of first conductor elements and the plurality of second conductor elements are formed as a winding rod made from an electrically conductive material.

10. The electrical machine according to claim 9 , wherein:
at least one winding rod as a rectangular geometry with two narrow sides and with two wide sides in a cross section perpendicular to the axial direction.

11. The electrical machine according to claim 7 , wherein the plurality of first conductor elements are electrically insulated from the plurality of second conductor elements by way of the at least one phase insulation.

12. The electrical machine according to claim 1 , wherein at least one of the second plastic and the third plastic forms a protective coating arranged in the intermediate space and at least partly at least one of delimits and surrounds the at least one cooling channel in a cross section perpendicular to the axial direction.

13. The electrical machine according to claim 12 , wherein the protective coating at least one of radially inwardly and radially outwardly delimits the at least one cooling channel in the cross section perpendicular to the axial direction.

14. The electrical machine according to claim 12 , wherein the protective coating delimits the at least one cooling channel in a circumferential direction of the stator in the cross section perpendicular to the axial direction.

15. The electrical machine according to claim 1 , wherein an additional cooling channel is arranged in a region of a radially outer end section or of a radially inner end section of the intermediate space.

16. The electrical machine according to claim 15 , wherein the third plastic forms a further protective coating arranged in the intermediate space and surrounds an entire perimeter of the additional cooling channel in the cross section perpendicular to the axial direction.

17. The electrical machine according to claim 16 , wherein the further protective coating at least one of radially inwardly and radially outwardly delimits the additional cooling channel in the cross section perpendicular to the axial direction.

18. The electrical machine according to claim 16 , wherein the further protective coating at least one of delimits and surrounds the additional cooling channel in the circumferential direction of the stator in the cross section perpendicular to the axial direction.

19. The electrical machine according to claim 1 , wherein:
the first plastic provided on surface sections of the stator teeth is formed by an electrically insulating first plastic material,
the second plastic is formed by a second plastic material; and
the third plastic at least partly at least one of delimits and surrounds the at least one cooli

Assignees

• Mahle Int Gmbh

Inventors

• E Silva Roberto Almeida
• Blankenbach Bernd
• Cox Terry
• Grabherr Philip
• Kull Niklas
• Male Tim
• Pisek Peter
• Sever Peter
• Sonntag Josef
• Williams Martin

Classifications

• H02K9/197

  in which the rotor or stator space is fluid-tight, e.g. to provide for different cooling media for rotor and stator · CPC title

• H02K9/227

  Heat sinks · CPC title

• H02K3/345

  between conductor and core, e.g. slot insulation · CPC title

• H02K3/30

  Windings characterised by the insulating material · CPC title

• H02K3/34

  between conductors or between conductor and core, e.g. slot insulation · CPC title