Dynamoelectric machine with diamagnetic flux shield

• US 4,908,347 A
• Filed: 07/07/1988
• Issued: 03/13/1990
• Est. Priority Date: 11/20/1985
• Status: Expired due to Term

• Current Assignee: Alliedsignal Inc. (Honeywell International Inc.)
• Original Assignee: Alliedsignal Inc. (Honeywell International Inc.)
• Inventors: Denk, Joseph
• Primary Examiner(s): Salce, Patrick R.
• Assistant Examiner(s): Peckman, Kristine
• Application Number:
  US07/217,729
• Time in Patent Office: 614 Days
• Field of Search: 310/40 R, 310/52, 310/58, 310/59, 310/71, 310/89, 310/184, 310/208, 310/254, 505/876, 505/877, 505/878, 505/701
• US Class Current: 505/166
• CPC Class Codes: H02K 1/02 characterised by the magnetic material
• CPC Class Codes: H02K 1/12 Stationary parts of the magnetic circuit
• CPC Class Codes: H02K 11/00 Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection casings, enclosures or supports H02K5/00
• CPC Class Codes: H02K 11/014 Shields associated with stationary parts, e.g. stator cores
• CPC Class Codes: H02K 3/47 Air-gap windings, i.e. iron-free windings
• CPC Class Codes: H02K 55/02 of the synchronous type
• CPC Class Codes: H02K 9/197 in which the rotor or stator space is fluid-tight, e.g. to provide for different cooling media for rotor and stator
• CPC Class Codes: Y02E 40/60 Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment
• CPC Class Codes: Y10S 505/701 Coated or thin film device, i.e. active or passive
• CPC Class Codes: Y10S 505/876 Electrical generator or motor structure
• CPC Class Codes: Y10S 505/877 Rotary dynamoelectric type
• CPC Class Codes: Y10S 505/878 with cooling

Abstract

An AC electrical machine which includes a superconducting, diamagentic flux shield cylinder enclosing the stator windings such that the magnetic flux produced by the machine'"'"'s rotor is bottled within the flux shield.

Claims

1. A stator for a dynamoelectric machine comprising:

a plurality of stator windings;

winding support means of non-magnetic material for supporting and separating said plurality of stator windings;

a cylindrical flux shield of diamagnetic material mounted around the outer periphery of said winding support means and said stator windings to contain a magnetic field internally to said flux shield.

2. The stator of claim 1 wherein said diamagnetic material of said flux shield is a metal oxide based ceramic compound.

3. The stator of claim 1 wherein said stator windings comprise a plurality of fully transposed fine strands of wire.

4. The stator of claim 3 wherein said fine strands of wire are insulated copper wires.

5. The stator of claim 3 wherein said fine strands of wire are insulated aluminum wires.

6. The stator of claim 1 wherein said stator windings are insulated superconducting wires.

7. The stator of claim 1 wherein said winding support means comprises a generally cylindrical support structure having a plurality of radially outwardly projecting fins aligned with the axis of said cylinder to define therebetween a plurality of winding slots.

8. A dynamoelectric machine comprising:

a rotor means for producing a high strength magnetic field;

at least one stator winding disposed about said rotor means;

means for supporting said stator winding, said means for supporting formed of non-magnetic material;

a substantially cylindrical flux shield means of superconducting diamagnetic materials, mounted around said stator winding and said means for supporting, for containing the magnetic field produced by said rotor means internally to said flux shield means;

a housing for containing said rotor means, said stator winding, said means for supporting, and said flux shield means;

a winding lead conductor attached to said stator winding and adapted to be connected to an electrical device external to said housing; and

a power coupling shaft connected to said rotor means and adapted to be coupled with a mechanical device external to said housing.

9. The machine of claim 8 wherein said superconducting diamagnetic materials are metal oxide based ceramic compounds.

10. The machine of claim 8 wherein said metal oxide based ceramic compounds have the chemical formula Y Ba₂ Cu₃ O_7-x.

11. The machine of claim 8 wherein said rotor means comprises:

a solid cylinder of high magnetic strength magnetic material which is diametrically magnetized;

a pair of flux shield disks of diamagnetic material located adjacent the ends of said solid cylinder to prevent end flux leakage;

a cylindrical retaining sleeve of non-magnetic material mounted about said cylinder of high strength magnetic material and said flux shield disks; and

a pair of end pieces attached to said cylindrical retaining sleeve.

12. The machine of claim 11 wherein said diamagnetic material of said flux shield disks is a metal oxide based ceramic compound.

13. The machine of claim 8 further comprising:

spacer means of non-magnetic non-conducting material for shielding said stator winding from said flux shield.

14. The machine of claim 8 wherein said housing further includes a coolant fluid inlet port, and a coolant fluid outlet port to allow coolant fluid to be passed through said dynamoelectric machine in intimate contact with said stator winding and said flux shield means.