Assemblies and Methods for Cooling Electric Machines

• US 20140183986A1
• Filed: 03/08/2013
• Published: 07/03/2014
• Est. Priority Date: 12/31/2012
• Status: Active Grant

• Current Assignee: TECO-Westinghouse Motor Company (TECO Electric & Machinery Pte Ltd.)
• Original Assignee: TECO-Westinghouse Motor Company (TECO Electric & Machinery Pte Ltd.)
• Inventors: Kulkarni, Devdatta P., Rupertus, Gabriel, Chen, Edward, Ramsey, Lex
• Granted Patent: US 9,819,248 B2
• Time in Patent Office: Days
• US Class Current: 310/52
• CPC Class Codes: H02K 1/20 with channels or ducts for flow of cooling medium
• CPC Class Codes: H02K 1/32 with channels or ducts for flow of cooling medium
• CPC Class Codes: H02K 9/223 Heat bridges
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine
• CPC Class Codes: Y10T 29/49012 Rotor

Abstract

Cooling assemblies and methods, including, for example, at least one bar (e.g., electrically insulated and/or thermally conductive bar(s)), members (e.g., i-beams, rectangular members, and the like), stator laminations, rotor laminations, and/or combinations thereof, such as those configured to cool electric machines (e.g., electric motors and generators).

Claims

1. A cooling assembly for an electric machine, comprising:

a stator core comprising a plurality of laminations and having;

a first end;

a second end; and

a bore extending from the first end to the second end of the stator core and configured to accommodate at least a portion of a rotor, the bore characterized by a longitudinal axis;

where at least some laminations in the plurality of laminations comprise at least one opening positioned at least between the first end and the second end of the stator core; and

at least one bar disposed in the at least one opening, where the at least one bar is not hollow and is electrically insulated from the at least some laminations.

2. The cooling assembly of claim 1, further comprising:

a plurality of openings in at least some laminations in the plurality of laminations, the openings positioned at least between the first end and the second end of the stator core; and

a bar disposed in each of the plurality of openings, where the bar is not hollow and is electrically insulated from the at least some laminations;

where each opening in the plurality of openings is substantially equidistant from the longitudinal axis of the bore of the stator core.

3. The cooling assembly of claim 2, where at least some laminations in the plurality of laminations further comprises:

a plurality of layers of openings, each layer comprising a plurality of openings that are substantially equidistant from the longitudinal axis of the bore of the stator core.

4. The cooling assembly of claim 1, where the thermal conductivity of the at least one bar is equal to or greater than 20 W/m-K.

5. The cooling assembly of claim 1, where the dielectric strength of the at least one bar is equal to or greater than 40 V/mil.

6. The cooling assembly of claim 1, where the at least one bar comprises ceramic.

7. The cooling assembly of claim 1, further comprising:

an end plate disposed at the first end; and

an end plate disposed at the second end;

where the end plates are configured to prevent the at least one bar from moving longitudinally with respect to the plurality of openings.

8. The cooling assembly of claim 1, further comprising:

a plurality of members disposed between at least two adjacent laminations such that the at least two adjacent laminations form at least one channel that extends at least partially around the stator core.

9. A cooling assembly for an electric machine, comprising:

a rotor core comprising a plurality of laminations and having;

a first end;

a second end;

a bore extending from the first end to the second end of the rotor core and configured to accommodate at least a portion of a rotor shaft, the bore characterized by a longitudinal axis;

an end plate disposed at the first end; and

an end plate disposed at the second end;

where at least some laminations in the plurality of laminations comprise at least one opening positioned at least between the first end and the second end of the rotor core; and

at least one bar disposed in the at least one opening, where the at least one bar is electrically insulated from the at least some laminations.

10. The cooling assembly of claim 9, where the at least one opening extends from the first end to the second end, and the at least one bar disposed in the at least one opening extends from the first end to the second end.

11. The cooling assembly of claim 9, further comprising:

a plurality of openings in at least some laminations in the plurality of laminations positioned at least between the first end and the second end of the rotor core; and

a bar disposed in each of the plurality of openings, where the bar is electrically insulated from the at least some laminations;

where each opening in the plurality of openings is substantially equidistant from the longitudinal axis of the bore of the rotor core.

12. The cooling assembly of claim 9, where the thermal conductivity of the at least one bar is equal to or greater than 20 W/m-K.

13. The cooling assembly of claim 9, where the dielectric strength of the at least one bar is equal to or greater than 40 V/mil.

14. The cooling assembly of claim 9, where the at least one bar comprises ceramic.

15. The cooling assembly of claim 9, further comprising:

an end plate disposed at the first end; and

an end plate disposed at the second end;

where the end plates are configured to prevent the at least one bar from moving longitudinally with respect to the plurality of openings.

16. The cooling assembly of claim 9, further comprising:

a plurality of members disposed between at least two adjacent laminations such that the at least two adjacent laminations form at least one channel that extends at least partially around the rotor core.

17. A method of manufacturing a cooling assembly for an electric machine, comprising:

cutting at least one opening in at least some of a plurality of stator laminations such that when the at least some stator laminations are assembled, the at least one opening is positioned at least between a first end and a second end of a stator core;

assembling the plurality of stator laminations to form at least a portion of a stator core; and

disposing at least one bar in the at least one opening, where the at least one bar is not hollow and is electrically insulated from the at least some laminations.

18. The method of claim 17, where the at least one bar is disposed in the at least one opening of the at least some stator laminations prior to assembling the plurality of stator laminations.

19. The method of claim 17, further comprising:

disposing a plurality of members between at least two adjacent laminations of the plurality of stator laminations to form at least one channel at least partially around the stator core.

20. The method of claim 17, further comprising:

cutting at least one opening in at least some of a plurality of rotor laminations such that when the at least some rotor laminations are assembled, the at least one opening is positioned at least between a first end and a second end of a rotor core;

assembling the plurality of rotor laminations to form at least a portion of a rotor core;

disposing at least one bar in the at least one opening, where the at least one bar is electrically insulated from the at least some laminations; and

disposing the rotor core at least partially in a bore of the stator core.