Electric machine, stator for an electric machine and vehicle

Patent metadata

Field	Value
Publication number	US-10673312-B2
Application number	US-201515535532-A
Country	US
Kind code	B2
Filing date	Dec 15, 2015
Priority date	Dec 16, 2014
Publication date	Jun 2, 2020
Grant date	Jun 2, 2020

Abstract

A stator for an electric machine comprising a rotor and stator poles. At least one partial amount of stator poles each comprises a pole winding and a permanent magnet unit. A first magnetic flux induced by the permanent magnet unit is superimposed by a second magnetic flux is an electric voltage is applied to the pole winding or an electrical current is injected into the pole winding. A recess is arranged in the permanent magnet unit, which recess faces the rotor. An electric machine comprising a stator according to the invention, wherein the rotor is designed to change a magnetic resistance of a magnetic circuit, which extends through a permanent magnet unit of stator poles of the stator, according to the position of the rotor.

First claim

The invention claimed is:

1. A stator for an electric machine comprising a rotor, wherein the stator comprises stator poles, wherein at least one partial amount of the stator poles each comprises a pole winding and a permanent magnet unit, wherein a first magnetic flux induced by the permanent magnet unit is superimposed by a second magnetic flux if an electric voltage is applied to the pole winding or an electric current is injected into the pole winding,
a recess is arranged in the permanent magnet unit, which recess faces the rotor;
wherein the permanent magnet unit comprises a first permanent magnet and a second permanent magnet which is arranged in series with the first permanent magnet, with the same magnetic pole orientation, wherein the first and second permanent magnets in the series-connected arrangement are magnetically interconnected by means of a soft magnetic intermediate segment, and wherein the recess is arranged in the soft magnetic intermediate segment and the recess is located entirely circumferentially between the first and second permanent magnets.

2. The stator as claimed in claim 1 , wherein the recess is at least partially radially aligned with at least one of the first and second permanent magnets.

3. The stator as claimed in claim 1 , wherein the recess is configured in a transverse plane of the stator with a rectangular or trapezoidal cross-section.

4. The stator as claimed in claim 1 , wherein an opening in the recess tapers and/or expands in the direction of the rotor.

5. The stator as claimed in claim 1 , wherein the recess is a slot, the principal longitudinal axis of which is oriented transversely to a transverse plane of the stator.

6. The stator as claimed in claim 1 , wherein the recess is designed for the conveyance of a coolant and/or the recess is designed for the accommodation of a tube which is provided for the conveyance of a coolant, and/or the recess contains a filler material which is not ferromagnetic.

7. The stator as claimed in claim 1 , wherein at least one of the stator poles comprises two pole segments which are mechanically connected, and/or at least one of the stator poles comprises two pole segments which are mechanically connected.

8. An electric machine comprising a stator and a rotor, which is designed, at least within a first rotor position range, to complete a first magnetic circuit, wherein a permanent magnet unit of the stator pole magnetizes a pole winding of the stator pole in a first direction, wherein the rotor is moreover designed, at least within a second rotor position range, to complete a second magnetic circuit, wherein the permanent magnet unit magnetizes the pole winding of the stator pole in a second direction, which is in opposition to the first direction,
characterized in that
the stator is a stator as claimed in claim 1 .

9. A vehicle, wherein the vehicle comprises an electric machine as claimed in claim 8 .

10. The stator as claimed in claim 1 , wherein the first permanent magnet and the second permanent magnet each extend across an entire radial length of the stator.

11. The stator as claimed in claim 2 , wherein the recess extends over a full lateral surface of the soft magnetic intermediate segment, facing the rotor, and wherein the recess extends circumferentially over an entire distance between said first and second permanent magnets.

12. The stator as claimed in claim 1 , wherein the first and second permanent magnets extend radially to a radially inner surface of the stator.

13. An electric machine, comprising:
a stator disposed extending about an axis and including a plurality of stator poles;
each of the stator poles including at least one pole winding and at least one permanent magnet unit, wherein a first magnetic flux induced by the at least one permanent magnet unit is superimposed by a second magnetic flux if an electric voltage is applied to the at least one pole winding or if an electric current is injected into the pole winding;
the at least one permanent magnet unit including a first permanent magnet and a second permanent magnet arranged is series with one another and with the same magnetic pole orientation as one another;
the at least one permanent magnet unit further including a soft magnetic intermediate segment located between the first and second permanent magnets; and
a radial inner surface of the soft magnetic intermediate segment defining a recess, wherein the recess is located entirely circumferentially between the first and second permanent magnets.

14. The electric machine as claimed in claim 13 , wherein the first permanent magnet and the second permanent magnet each extend across an entire radial length of the stator.

15. The electric machine as claimed in claim 13 , wherein the recess is at least partially radially aligned with at least one of the first and second permanent magnets.

16. The electric machine as claimed in claim 15 , wherein the recess extends circumferentially over an entire distance between said first and second permanent magnets.

17. The electric machine as claimed in claim 13 , wherein the first and second permanent magnets extend radially to a radially inner surface of the stator.

Assignees

• Magna powertrain gmbh & co kg

Inventors

• Bouvier Stephan
• Pisek Peter
• Schmidhofer Andreas

Classifications

• H02K1/17

  Stator cores with permanent magnets · CPC title

• H02K1/20

  with channels or ducts for flow of cooling medium · CPC title

• H02K21/44 Primary

  with armature windings wound upon the magnets · CPC title