Interior permanent magnet electric machine

Patent metadata

Field	Value
Publication number	US-10056792-B2
Application number	US-201615145926-A
Country	US
Kind code	B2
Filing date	May 4, 2016
Priority date	Feb 5, 2016
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

Abstract

An interior permanent magnet electric machine is described, and includes a stator including a plurality of electrical windings and a rotor disposed in a cylindrically-shaped void formed within the stator. The rotor includes a plurality of steel laminations assembled onto a shaft, wherein the shaft defines a longitudinal axis. Each of the steel laminations includes a plurality of poles and each of the poles includes a plurality of slots disposed near an outer periphery. The slots of the steel laminations are longitudinally aligned. A plurality of permanent magnets are disposed in a first subset of the slots, and plurality of packets assembled from anisotropic material are disposed in a second subset of the slots.

First claim

The invention claimed is:

1. An interior permanent magnet electric machine, comprising:
a stator including a plurality of electrical windings;
a rotor disposed in a cylindrically-shaped void formed within the stator and including a plurality of steel laminations assembled onto a shaft,
wherein the shaft defines a longitudinal axis,
wherein each of the steel laminations includes a plurality of poles and wherein each of the poles includes a plurality of slots disposed near an outer periphery,
wherein the slots of the steel laminations are longitudinally aligned;

a plurality of permanent magnets; and
a plurality of packets assembled from anisotropic material;
wherein the plurality of permanent magnets are disposed in a first subset of the slots; and
wherein the plurality of packets assembled from anisotropic material are disposed in a second subset of the slots.

2. The interior permanent magnet electric machine of claim 1 , wherein the plurality of packets assembled from anisotropic material are disposed in the second subset of the slots in an axial orientation that is disposed parallel to the longitudinal axis.

3. The interior permanent magnet electric machine of claim 1 , wherein each of the packets assembled from anisotropic material comprises a stack including a plurality of laminations fabricated from a grain-oriented steel material, wherein the grain-oriented steel material of the plurality of laminations are aligned along a common axis.

4. The interior permanent magnet electric machine of claim 3 , wherein the common axis associated with the grain-oriented steel materials of the plurality of laminations is parallel with a d-axis associated with one of the poles of the rotor.

5. The interior permanent magnet electric machine of claim 3 , wherein the common axis associated with the grain-oriented steel materials of the plurality of laminations is aligned with an axis of low magnetic reluctance associated with one of the poles of the rotor.

6. The interior permanent magnet electric machine of claim 3 , wherein the plurality of laminations fabricated from a grain-oriented steel material are layered radially.

7. The interior permanent magnet electric machine of claim 3 , wherein the plurality of laminations fabricated from a grain-oriented steel material are layered axially.

8. The interior permanent magnet electric machine of claim 3 , wherein the grain-oriented steel material comprises an iron-silicon magnetic alloy.

9. The interior permanent magnet electric machine of claim 1 , wherein a third subset of the slots remain void.

10. The interior permanent magnet electric machine of claim 1 , wherein each of the steel laminations comprises a disc-shaped steel lamination.

11. The interior permanent magnet electric machine of claim 10 , wherein each of the disc-shaped steel laminations are fabricated from an isotropic material.

12. A rotor for an interior permanent magnet electric machine, the rotor comprising:
a plurality of steel laminations assembled onto a shaft, wherein the shaft defines a longitudinal axis, wherein each of the steel laminations includes a plurality of poles, wherein each of the poles includes a plurality of slots disposed near an outer periphery, and wherein the slots of the steel laminations are longitudinally aligned;
a plurality of permanent magnets; and
a plurality of packets assembled from anisotropic material, wherein the plurality of permanent magnets are disposed in a first subset of the slots and wherein the plurality of packets assembled from anisotropic material are disposed in a second subset of the slots.

13. The rotor of claim 12 , wherein the plurality of packets assembled from anisotropic material are disposed in the second subset of the slots in an axial orientation that is disposed parallel to the longitudinal axis.

14. The rotor of claim 12 , wherein each of the packets assembled from anisotropic material comprises a stack including a plurality of laminations fabricated from a grain-oriented steel material, wherein the grain-oriented steel material of the plurality of laminations are aligned along a common axis.

15. The rotor of claim 14 , wherein the common axis associated with the grain-oriented steel materials of the plurality of laminations is parallel with a d-axis associated with one of the poles of the rotor.

16. The rotor of claim 14 , wherein the common axis associated with the grain-oriented steel materials of the plurality of laminations is aligned with an axis of low magnetic reluctance associated with one of the poles of the rotor.

17. The rotor of claim 14 , wherein the plurality of laminations fabricated from a grain-oriented steel material are layered radially.

18. The rotor of claim 14 , wherein the plurality of laminations fabricated from a grain-oriented steel material are layered axially.

19. The rotor of claim 12 , wherein a third subset of the slots remain void.

20. The rotor of claim 12 , wherein the grain-oriented steel material comprises an iron-silicon magnetic alloy.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Rahman Khwaja M
• Stancu Constantin C
• Savagian Peter J
• Patel Nitinkumar R
• Dawsey Robert T

Classifications

• H02K21/14 Primary

  with magnets rotating within the armatures · CPC title

• H02K1/24

  Rotor cores with salient poles {; Variable reluctance rotors} · CPC title

• H02K1/2766

  having a flux concentration effect · CPC title

• H02K1/02 Primary

  characterised by the magnetic material · CPC title

• H02K21/021

  Means for mechanical adjustment of the excitation flux · CPC title