Auxiliary magnetizing winding for interior permanent magnet rotor magnetization

• US 6,674,205 B2
• Filed: 05/07/2002
• Issued: 01/06/2004
• Est. Priority Date: 05/07/2002
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Rahman, Khwaja M., Biais, Francois J.
• Primary Examiner(s): Dougherty, Thomas M.
• Assistant Examiner(s): Mohandesi, Iraj A.
• Application Number:
  US10/140,918
• Publication Number:
  US 20030209950A1
• Time in Patent Office: 609 Days
• Field of Search: 310/156.53, 310/156, 310/44, 310/181, 335/284
• US Class Current: 310/156.53
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2220/50 Structural details of electrical machines
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/425 Temperature
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: H02K 1/274 the rotor consisting of two or more circumferentially positioned magnets
• CPC Class Codes: H02K 1/2766 having a flux concentration effect
• CPC Class Codes: H02K 15/03 having permanent magnets
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A method and apparatus for fabricating a rotor for an electric traction motor including forming cavities in the rotor, injecting magnetic material in a portion of the cavities, configuring an electrical winding in a portion of the cavities, and post-magnetizing the magnetic material.

Claims

1. An electric traction motor for a vehicle comprising:

a housing;

a wound stator field located in said housing;

a rotor magnetically interacting with said wound stator field, said rotor including a permanent magnet;

air spaces configured in said rotor;

windings located in said air spaces;

an

wherein said permanent magnet is post-magnetized in said rotor by said windings located in said air spaces.

2. The electric traction motor of claim 1 wherein said permanent magnet is an interior permanent magnet.

3. The electric traction motor of claim 1 further including an array of permanent magnets configured as interior permanent magnets.

4. The electric traction motor of claim 3 wherein said array of permanent magnets comprises sintered magnets.

5. The electric traction motor of claim 1 wherein said interior permanent magnet comprises magnetic powder.

6. The electric traction motor of claim 1 further including multi-layers of permanent magnets.

7. The electric traction motor of claim 1 wherein said interior permanent magnet is injected into said rotor in liquid form.

8. The electric traction motor of claim 1 wherein said air spaces are partially filled with a heat conducting material.

9. An electric traction motor comprising:

a housing;

a wound stator field located in said housing;

a rotor magnetically interacting with said wound stator field, said rotor including an array of cavities;

an electrical winding configured in said array of cavities; and

wherein said electrical windings configured in said array of cavities post-magnetize magnetic material located in said rotor.

10. The electric traction motor of claim 9 wherein said magnetic material comprises a moldable magnet.

11. The electric traction motor of claim 10 wherein said binder is plastic.

12. The electric traction motor of claim 9 wherein a portion of said array of cavities is filled with inert material.

13. A method of fabricating a rotor for an electric traction motor comprising the steps of:

forming cavities in the rotor;

injecting magnetic material in a portion of the cavities;

configuring an electrical winding in a portion of the cavities; and

post-magnetizing the magnetic material.

14. The method of claim 13 further comprising the step of removing the electrical winding from the cavities.

15. The method of claim 13 further comprising the step of bonding said magnetic material with a plastic.

16. An electric traction motor comprising:

a housing;

a wound stator field located in said housing;

a rotor magnetically interacting with said wound stator field, said rotor including an array of cavities;

magnetic material configured in said rotor;

an electrical winding configured in said array of cavities; and

wherein said electrical windings configured in array of cavities and said wound stator field post-magnetize said magnetic material located in said rotor.

17. The electric traction motor of claim 16 wherein said magnetic material is comprises a bonded magnetic powder mixed in some proportion with a binder.

18. The electric traction motor of claim 16 wherein said magnetic is injected into said rotor in liquid form.

19. An electric traction motor of a vehicle comprising:

a housing;

a wound stator field located in said housing;

a rotor magnetically interacting with said wound stator field, said rotor including permanent magnet;

air spaces configured in said rotor;

windings located in said air spaces; and

wherein said permanent magnet is post-magnetized in said rotor by said windings located in said air spaces and said wound stator field.