Electric machine

Patent metadata

Field	Value
Publication number	US-2022014062-A1
Application number	US-201917295328-A
Country	US
Kind code	A1
Filing date	Nov 15, 2019
Priority date	Nov 19, 2018
Publication date	Jan 13, 2022
Grant date	—

Abstract

An electric machine may include a rotor and at least one cooling channel. The rotor may be rotatable about an axis defining an axial direction and include a stator having electrically conductive stator windings. A coolant may flow through the at least one cooling channel to the cool the stator windings. The stator may include teeth extending along the axial direction. The at least one cooling channel and the stator windings may be arranged in at least one intermediate space formed between two adjacent stator teeth. A plastic for transmitting heat from the stator windings to the at least one cooling channel may be arranged in the intermediate space.

First claim

1 . An electric machine, comprising:
a rotor rotatable about an axis of rotation which defines an axial direction and including a stator having electrically conductive stator windings; and at least one cooling channel through which a coolant can flow to cool the stator windings, wherein the stator has stator teeth which extend along the axial direction, are arranged at a distance from one another along a circumferential direction of the rotor, and carry the stator windings, wherein the at least one cooling channel and the stator windings are arranged in at least one intermediate space formed between two adjacent stator teeth in the circumferential direction, wherein a plastic for transmitting heat from the stator windings to the at least one cooling channel is arranged in the intermediate space.

2 . The electric machine as claimed in claim 1 , wherein
the plastic is arranged on surface portions of the two adjacent stator teeth bounding the intermediate space.

3 . The electric machine as claimed in claim 1 , wherein
the stator includes a stator body from which the stator teeth protrude radially inward, and wherein the plastic is arranged on a surface portion of the stator body which bounds the intermediate space radially on the outside.

4 . The electric machine as claimed in claim 3 , wherein
the plastic forms an electrically insulating insulation layer which covers the surface portions of the two adjacent stator teeth.

5 . The electric machine as claimed in claim 2 ,
wherein the at least one cooling channel is arranged in a region of a radially inner end portion of the intermediate space.

6 . The electric machine as claimed in claim 5 ,
wherein the plastic forms at least one phase insulation which divides the intermediate space into a radially inner and a radially outer partial space, and wherein first conductor elements of the stator winding are arranged in the radially inner partial space and form a first phase winding, and second conductor elements of the stator winding are arranged in the radially outer partial space and form a second phase winding electrically insulated from the first phase winding.

7 . The electric machine as claimed in claim 6 ,
wherein the at least one phase insulation extends along the circumferential direction and connects two insulation layers arranged on the adjacent stator teeth.

8 . The electric machine as claimed in claim 6 ,
wherein the stator winding includes first conductor elements and second conductor elements, the first conductor elements are arranged in the radially inner partial space and are electrically connected to one another for the connection to a common first phase of an electric power source, and wherein the second conductor elements are arranged in the radially outer partial space and are electrically connected to one another for the connection to a common second phase of the electric power source.

9 . The electric machine as claimed in claim 8 ,
wherein the first and second conductor elements are surrounded by the plastic in a cross section perpendicular to the axial direction.

10 . The electric machine as claimed in claim 9 ,
wherein the first and second conductor elements are formed as winding bars made from an electrically conductive material.

11 . The electric machine as claimed in claim 10 ,
wherein the winding bars have a geometry of a right angle including two narrow sides and two wide sides in the cross section perpendicular to the axial direction.

12 . The electric machine as claimed in claim 11 ,
wherein the first conductor elements are electrically insulated from the second conductor elements via the phase insulation.

13 . The electric machine as claimed in claim 8 ,
wherein an additional cooling channel is arranged in a region of a radially outer end portion of the intermediate space.

14 . The electric machine as claimed in claim 13 ,
wherein the at least one cooling channel is arranged in the radially inner partial space formed via the phase insulation of plastic, and wherein the additional cooling channel is arranged in the radially outer partial space formed via the phase insulation of plastic.

15 . The electric machine as claimed in claim 14 ,
wherein a gap is formed between two first conductor elements or between one first and second conductor element, and wherein the plastic forms a gap filling with which the gap ( 63 ) is at least partially filled.

16 . The electric machine as claimed in claim 1 ,
wherein the plastic comprises a plastics compound in which the stator winding is embedded.

17 . The electric machine as claimed in claim 1 ,
wherein the intermediate space has geometry of a trapezoid or a rectangle in a cross section perpendicular to the axial direction.

18 . The electric machine as claimed in claim 7 ,
wherein the plastic provided on the surface portions of the stator teeth is formed by an electrically insulating first plastic material, and wherein the plastic forming the at least one phase insulation is formed by a second plastic material, and wherein the plastic forming a protective coating is formed by the second plastic material or by a third plastic material.

19 . The electric machine as claimed in claim 18 ,
wherein the second plastic material is configured to be electrically insulating or electrically conductive, and wherein the third plastic material is configured to be electrically insulating or electrically conductive.

20 . The electric machine as claimed in claim 19 ,
wherein the first, second, and third plastic materials are a thermoplastic or a thermosetting plastic.

21 . The electric machine as claimed in claim 20 ,
wherein the first, second, and third materials have identical heat have different heat conductivities.

22 . The electric machine as claimed in claim 21 ,
wherein the first, the second, and third plastic materials are identical materials.

23 . The electric machine as claimed in claim 1 ,
wherein the stator is windings are a part of a distributed winding.

24 . The electric machine as claimed in claim 22 ,
wherein the heat conductivity of the first, second, and third plastic materials are at least 0.5 W/m K.

25 . The electric machine as claimed in claim 1 ,
wherein the intermediate space is formed to be substantially free of gaps or air inclusions.

Assignees

• Mahle Int Gmbh

Inventors

• Almeida E Silva Roberto
• 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

• H02K9/223

  Heat bridges · CPC title

• H02K3/24 Primary

  with channels or ducts for cooling medium between the conductors · CPC title

• H02K9/227

  Heat sinks · CPC title

• H02K3/345

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