AIRCRAFT ENGINE STARTER/GENERATOR

• US 20130207395A1
• Filed: 02/13/2012
• Published: 08/15/2013
• Est. Priority Date: 02/13/2012
• Status: Active Grant

• Current Assignee: GE Aviation Systems LLC (GE Aerospace)
• Original Assignee: GE Aviation Systems LLC (GE Aerospace)
• Inventors: Huang, Hao, Jia, Xiaochuan, Wirsch, Paul James Jr.
• Granted Patent: US 9,559,569 B2
• Time in Patent Office: Days
• US Class Current: 290/46
• CPC Class Codes: H02K 2213/03 Machines characterised by numerical values, ranges, mathematical expressions or similar information
• CPC Class Codes: H02K 3/24 with channels or ducts for cooling medium between the conductors
• CPC Class Codes: H02K 3/30 Windings characterised by the insulating material
• CPC Class Codes: H02K 3/325 for windings on salient poles, such as claw-shaped poles
• CPC Class Codes: H02K 3/38 around winding heads, equalising connectors, or connections thereto
• CPC Class Codes: H02K 5/203 specially adapted for liquids, e.g. cooling jackets
• CPC Class Codes: H02K 9/227 Heat sinks

Abstract

An assembly for a gas turbine engine includes a S/G having a rotatable shaft, a main machine, a PMG, and an exciter wherein at least one of the main machine, PMG, and exciter includes a rotor mounted to the shaft and having multiple rotor poles, a stator having multiple stator poles and at least one of the rotor poles and stator poles being formed by a core with a post and wire wound about the post to form a winding, with the winding having at least one end turn, and a layer to increase cooling capabilities of a portion of at least one of the stator and the rotor.

Claims

1. An electric machine comprising:

a rotor having multiple rotor poles;

a stator having multiple stator poles;

at least one of the rotor poles and stator poles being formed by a core with a post and wire wound about the post to form a winding, with the winding having at least one end turn; and

a layer of thermally conducting and electrically insulating material provided adjacent the winding.

2. The electric machine of claim 1, further comprising a cooling system having at least one cooling circuit passing adjacent the core and the at least one end turn to exchange heat with the core and the at least one end turn without wetting the winding.

3. The electric machine of claim 2, further comprising at least one coil support adjacent the cooling system and configured to support the stator.

4. The electric machine of claim 3 wherein the layer of thermally conducting and electrically insulating material is provided between the at least one end turn and the at least one coil support.

5. The electric machine of claim 4 wherein there are multiple end turns and the layer is provided between each of the end turns and the at least one coil support.

6. The electric machine of claim 5 wherein there are multiple windings, with each winding having at least one end turn to form the multiple end turns.

7. The electric machine of claim 6 wherein each of the multiple windings has multiple end turns.

8. The electric machine of claim 7 wherein the layer comprises a mixture including boron nitride.

9. The electric machine of claim 1, further comprising a cooling system having at least one cooling circuit passing through the core to exchange heat with the core without wetting the winding.

10. The electric machine of claim 9 wherein the cooling system further comprises at least one cooling fin mounted to a portion of the at least one cooling circuit.

11. The electric machine of claim 9 wherein the layer of thermally conducting and electrically insulating material is provided between the winding and the at least one cooling fin.

12. The electric machine of claim 1 wherein the layer has a thermal conductivity greater than 0.75 W/mC.

13. The electric machine of claim 12 wherein the layer has a minimum dielectric strength of 250 V/mil.

14. The electric machine of claim 12 wherein the layer comprises boron nitride.

15. The electric machine of claim 14 wherein the layer comprises a mixture including boron nitride.

16. The electric machine of claim 15 wherein the winding is coated with the mixture.

17. The electric machine of claim 12 wherein the rotor further comprises a rotatable shaft.

18. The electric machine of claim 17 wherein the stator defines an interior through which the rotatable shaft extends.

19. The electric machine of claim 1 wherein the electric machine is one of a main machine, an exciter, and a permanent magnet generator.

20. An assembly for a gas turbine engine comprising:

an accessory gearbox;

a starter/generator mechanically mounted to the accessory gearbox, comprising;

a rotatable shaft;

a main machine carried by the shaft;

a permanent magnet generator (PMG) carried by the shaft;

an exciter carried by the shaft;

wherein at least one of the main machine, PMG, and exciter comprises;

a rotor mounted to the shaft and having multiple rotor poles;

a stator having multiple stator poles;

at least one of the rotor poles and stator poles being formed by a core with a post and wire wound about the post to form a winding, with the winding having at least one end turn; and

a layer of thermally conducting and electrically insulating material provided adjacent the winding.

21. The assembly of claim 20, further comprising a cooling system having at least one cooling circuit passing through the core to exchange heat with the core without wetting the winding.

22. The assembly of claim 20 wherein the layer has a thermal conductivity greater than 0.75 W/mC.

23. The assembly of claim 22 wherein the layer has a minimum dielectric strength of 250 V/mil.

24. The assembly of claim 23 wherein the layer comprises boron nitride.