Cooling arrangement of an electrical machine

• US 20080197724A1
• Filed: 01/23/2008
• Published: 08/21/2008
• Est. Priority Date: 02/16/2007
• Status: Active Grant

• Current Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Inventors: Cullen, John J. A., Powell, David J.
• Granted Patent: US 8,487,500 B2
• Time in Patent Office: Days
• US Class Current: 310/53
• CPC Class Codes: H02K 3/24 with channels or ducts for cooling medium between the conductors
• CPC Class Codes: H02K 9/00 Arrangements for cooling or ventilating channels or ducts in parts of the magnetic circuit H02K1/20, H02K1/32; channels or ducts in or between conductors H02K3/22, H02K3/24

Abstract

A component of an electric machine 46, the component comprising a core 10; two or more teeth 14 extending radially therefrom; at least one electromagnetic winding 12, each winding 12 around at least one of the teeth 14; wherein the core 10 having a cooling arrangement including at least one cooling insert 48 located between adjacent windings 12 and whereby in use a cooling fluid being arranged to flow through the at least one cooling insert 48 to facilitate heat transfer and dissipation from the electromagnetic windings 12. The cooling inserts providing improved cooling, structural support to the windings, and electrical insulation between the windings and the core.

Claims

1. A component of an electric machine, the component comprising a core;

two or more teeth extending radially from the core;

at least one electromagnetic winding, each winding being arranged around at least one of the teeth;

wherein the core having a cooling arrangement including at least one cooling insert located between adjacent windings, the cooling insert comprising a material with high thermal conductivity and low electrical conductivity, and whereby in use a cooling fluid being arranged to flow through the at least one cooling insert to facilitate heat transfer and dissipation from the electromagnetic windings.

2. A component as claimed in claim 1 wherein there is an annular array of teeth.

3. A component as claimed in claim 1 wherein there is at least one annular array of cooling inserts.

4. A component as claimed in claim 1 wherein the cooling insert comprises a ceramic.

5. A component as claimed in claim 1 wherein the cooling insert is a casting.

6. A component as claimed in claim 1 wherein the cooling insert comprises aluminium nitride.

7. A component as claimed in claim 1 wherein the cooling insert comprises silicon carbide.

8. A component as claimed in claim 1 wherein the cooling insert is generally tapering in cross section.

9. A component as claimed in claim 1 wherein the cooling insert is bonded to the core.

10. A component as claimed in claim 1 wherein the cooling insert is bonded to the windings.

11. A component as claimed in claim 1 wherein the cooling insert is hollow and the cooling insert defines at least one cooling duct therethrough for a flow of cooling fluid.

12. A component as claimed in claim 1 wherein the cooling insert is porous to allow a flow of cooling fluid therethrough.

13. A component as claimed in claim 1 wherein each tooth has a winding around it.

14. A component as claimed in claim 1 wherein the cooling inserts are located between circumferentially adjacent windings.

15. A component as claimed in claim 1 wherein the cooling inserts are located between radially adjacent windings.

16. A component as claimed in claim 1 wherein at least two cooling inserts are in fluid communication with a cooling fluid inlet manifold to provide a constant flow of cooling fluid to the cooling inserts.

17. A component as claimed in claim 1 wherein at least two cooling inserts are in fluid communication with a cooling fluid outlet manifold to facilitate heat dissipation from the cooling inserts.

18. A component as claimed in claim 1 wherein a metering arrangement is provided upstream of the cooling insert to optimise the flow rate of cooling fluid for a given running condition.

19. A component as claimed in claim 1 wherein a means to supply a cooling fluid comprises an air source.

20. A component as claimed in claim 19 wherein the air source is a bypass duct or a compressor of a gas turbine engine.

21. A component as claimed in claim 1 wherein the component is a stator component of an electric machine.

22. A component as claimed in claim 1 wherein the component is a rotor component of an electric machine.

23. An electric machine comprising a component as claimed in claim 1.