Variable magnetic flux-type permanent magnet rotary electric machine

Patent metadata

Field	Value
Publication number	US-11088604-B2
Application number	US-201816046452-A
Country	US
Kind code	B2
Filing date	Jul 26, 2018
Priority date	Sep 27, 2017
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

Provided is a variable magnetic flux-type permanent magnet rotary electric machine wherein a leakage magnetic flux leaking from a certain permanent magnet included in the rotor core to a permanent magnet circumferentially adjacent on either side of the certain permanent magnet is controlled by q-axis current and thereby a magnetic flux emanating from the certain permanent magnet and linking with the armature coil wound on the stator is controlled without forming a mechanically weak part in the rotor core.

First claim

The invention claimed is:

1. A variable magnetic flux-type permanent magnet rotary electric machine comprising:
a stator including an armature coil wound on a stator core;
a rotor rotatably disposed inside the stator core of the stator with an air gap between the rotor and the stator core, the rotor including a cylindrical rotor core with a plurality of magnet slots disposed in a circumferential direction and a plurality of magnetic poles including a plurality of permanent magnets respectively fixed in the plurality of magnet slots, and
a nonmagnetic part formed between adjacent magnetic poles of the rotor core and radially outward of the magnet slots,
wherein a leakage magnetic flux leaking from a certain permanent magnet among the plurality of permanent magnets to a permanent magnet circumferentially adjacent on either side of the certain permanent magnet is controlled by q-axis current, a magnetic flux emanating from the certain permanent magnet and linking with the armature coil is controlled, and a magnetic flux bypass path for the leakage magnetic flux leaking from the certain permanent magnet to the permanent magnet circumferentially adjacent on either side of the certain permanent magnet is formed in a portion between the magnet slot for fixing the certain permanent magnet and the nonmagnetic part, in a portion radially inward of the nonmagnetic part, and in a portion between the nonmagnetic part and the magnet slot for fixing the permanent magnet circumferentially adjacent on either side of the certain permanent magnet.

2. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 1 , wherein a plurality of the nonmagnetic parts is formed in all portions between adjacent magnetic poles of the rotor core.

3. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 1 , wherein a plurality of the nonmagnetic parts is formed in alternate portions between adjacent magnetic poles of the rotor core.

4. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 1 , wherein an auxiliary magnet is disposed radially inward of the nonmagnetic part of the rotor core.

5. The variable magnetic flux-type permanent magnet rotary electric machine according to of claim 1 , wherein a magnet slot connection part connecting adjacent the magnet slots of the rotor core is rendered nonmagnetic.

6. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 1 , wherein a hole is formed in a magnet slot connection part connecting adjacent the magnet slots of the rotor core.

7. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 1 , wherein each of the plurality of magnet slots and each of the plurality of permanent magnets are separated into two or more per one magnetic pole and wherein a communication hole is formed in a magnet slot connection part connecting adjacent the magnet slots to enable communication between the adjacent magnet slots.

8. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 1 , wherein the nonmagnetic part includes an air gap formed at a certain distance radially inward from an outer circumferential surface of the rotor core.

9. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 1 , wherein the nonmagnetic part includes a groove formed concavely on an outer circumferential surface of the rotor core.

10. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 2 , wherein a plurality of the nonmagnetic parts is formed in alternate portions between adjacent magnetic poles of the rotor core.

11. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 2 , wherein an auxiliary magnet is disposed radially inward of the nonmagnetic part of the rotor core.

12. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 3 , wherein an auxiliary magnet is disposed radially inward of the nonmagnetic part of the rotor core.

13. The variable magnetic flux-type permanent magnet rotary electric machine according to of claim 2 , wherein a magnet slot connection part connecting adjacent the magnet slots of the rotor core is rendered nonmagnetic.

14. The variable magnetic flux-type permanent magnet rotary electric machine according to of claim 3 , wherein a magnet slot connection part connecting adjacent the magnet slots of the rotor core is rendered nonmagnetic.

15. The variable magnetic flux-type permanent magnet rotary electric machine according to of claim 4 , wherein a magnet slot connection part connecting adjacent the magnet slots of the rotor core is rendered nonmagnetic.

16. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 2 , wherein a hole is formed in a magnet slot connection part connecting adjacent the magnet slots of the rotor core.

17. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 3 , wherein a hole is formed in a magnet slot connection part connecting adjacent the magnet slots of the rotor core.

18. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 4 , wherein a hole is formed in a magnet slot connection part connecting adjacent the magnet slots of the rotor core.

19. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 2 , wherein each of the plurality of magnet slots and each of the plurality of permanent magnets are separated into two or more per one magnetic pole and wherein a communication hole is formed in a magnet slot connection part connecting adjacent the magnet slots to enable communication between the adjacent magnet slots.

20. The variable magnetic flux-type permanent magnet rotary electric machine according to claim 3 , wherein each of the plurality of magnet slots and each of the plurality of permanent magnets are separated into two or more per one magnetic pole and wherein a communication hole is formed in a magnet slot connection part connecting adjacent the magnet slots to enable communication between the adjacent magnet slots.

Assignees

• Fuji Electric Co Ltd

Inventors

• Oguchi Hideki
• Terajima Makoto
• Nakazono Hitoshi

Classifications

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title

• H02K1/276

  Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] · CPC title

• H02K21/14

  with magnets rotating within the armatures · CPC title

• H02K1/2766

  having a flux concentration effect · CPC title

• H02K1/2773 Primary

  consisting of tangentially magnetized radial magnets · CPC title