Synchronous machine rotor

• US 5,736,803 A
• Filed: 09/15/1994
• Issued: 04/07/1998
• Est. Priority Date: 09/21/1993
• Status: Expired due to Fees

• Current Assignee: GEC Alsthom Transport SA (Alstom SA)
• Original Assignee: GEC Alsthom Transport SA (Alstom SA)
• Inventors: Masson, Andre
• Primary Examiner(s): Dougherty, Thomas M.
• Assistant Examiner(s): Link, Jonathan
• Application Number:
  US08/306,597
• Time in Patent Office: 1,300 Days
• Field of Search: 310/261, 310/162, 310/183, 310/197, 310/263, 310/269, 310/214, 310/154, 310/156
• US Class Current: 310/156.46
• CPC Class Codes: H02K 1/08 Salient poles
• CPC Class Codes: H02K 1/24 Rotor cores with salient poles ; Variable reluctance rotors
• CPC Class Codes: H02K 3/20 for auxiliary purposes, e.g. damping or commutating

Abstract

A synchronous machine rotor has a progressive magnetic airgap and a constant aerodynamic airgap.

Claims

1. A synchronous machine rotor having poles and being associated with a stator, wherein a surface of one of said poles defines a first surface and an outer surface of said rotor defines a second surface, there being a magnetic airgap between said first surface and said second surface of said stator, said magnetic airgap being progressive in a progressive magnetic airgap area of only one side of said pole, said aerodynamic airgap being constant, said progressive magnetic airgap area including a tangential edge area disposed at an edge of said pole and a centrally disposed area disposed closer to the center of said pole than said tangential edge area, and said progressive magnetic airgap being thinner at said centrally disposed area than at said tangential edge area;

and having at least one amagnetic material progressive magnetic airgap area.

2. Synchronous machine rotor according to claim 1 having poles which include a curved surface at the center and a plane surface in at least one of said progressive magnetic airgap areas and at least one sharp edge.

3. Synchronous machine rotor according to claim 1 having poles which include a curved surface at the center and a plane surface in at least one of said progressive magnetic airgap areas and at least one bevelled edge.

4. Synchronous machine rotor according to claim 1 having poles which include a curved surface at the center and a plane surface in at least one of said progressive magnetic airgap areas and at least one rounded edge.

5. Synchronous machine rotor according to claim 1 having poles which include a curved surface at the center and in at least one of said progressive magnetic airgap areas and at least one sharp edge.

6. Synchronous machine rotor according to claim 1 having poles which include a curved surface at the center and in at least one of said progressive magnetic airgap areas and at least one bevelled edge.

7. Synchronous machine rotor according to claim 1 having poles which include a curved surface at the center and in at least one of said progressive magnetic airgap areas and at least one rounded edge.

8. Synchronous machine rotor according to claim 1 having wedge members which are complemented by lateral members to constitute an electrically conductive amagnetic material damper turn.

9. A synchronous rotor associated with a stator, comprising:

a plurality of poles, each pole having a cross-section defining a curved outer surface, flanking surfaces, and a progressive surface between said curved outer surface and a particular one of said flanking surfaces;

adjacent ones of said plurality of poles being separated by an amagnetic member contacting one of said flanking surfaces of each adjacent pole;

said progressive surface having a first end thereof closest to said curved outer surface and a second end thereof closest to said particular one of said flanking surfaces, said second end forming an edge with said particular one of said flanking surfaces;

wherein;

said curved outer surface and said progressive surface define a first surface,

an outer surface of said rotor defines a second surface,

there is a magnetic airgap between said first surface and a surface of said stator, and an aerodynamic airgap between said second surface and said surface of said stator,

said magnetic airgap at said progressive surface is progressive and defines a progressive magnetic airgap area, and is thinner at said first end of said progressive surface than at said second end of said progressive surface,

said aerodynamic airgap is constant, and

an amagnetic material is disposed in said progressive magnetic airgap area.

10. The synchronous machine rotor according to claim 9 wherein said progressive surface is a plane surface and said edge is a sharp edge.

11. The synchronous machine rotor according to claim 9 wherein said progressive surface is a plane surface and said edge is a beveled edge.

12. The synchronous machine rotor according to claim 9 wherein said progressive surface is a plane surface and said edge is a rounded edge.

13. The synchronous machine rotor according to claim 9 wherein said progressive surface is a curved surface and said edge is a sharp edge.

14. The synchronous machine rotor according to claim 9 wherein said progressive surface is a curved surface mad said edge is a beveled edge.

15. The synchronous machine rotor according to claim 9 wherein said progressive surface is a curved surface and said edge is a rounded edge.

16. The synchronous machine rotor according to claim 9 having wedge members which are complemented by lateral members to constitute an electrically conductive amagnetic material damper turn.

17. The synchronous machine rotor according to claim 9 wherein each of said plurality of poles has only one progressive magnetic airgap area.