ELECTRIC MACHINE WITH FLUID COOLED STATOR ASSEMBLY

• US 20200136470A1
• Filed: 10/31/2018
• Published: 04/30/2020
• Est. Priority Date: 10/31/2018
• Status: Active Grant

• Current Assignee: Rolls-Royce Corporation (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce Corporation (Rolls-Royce Holdings Plc)
• Inventors: Banham, Christopher
• Granted Patent: US 11,211,849 B2
• Time in Patent Office: Days
• CPC Class Codes: H02K 1/20 with channels or ducts for flow of cooling medium
• CPC Class Codes: H02K 2209/00 Specific aspects not provided for in the other groups of this subclass relating to systems for cooling or ventilating
• CPC Class Codes: H02K 5/203 specially adapted for liquids, e.g. cooling jackets

Abstract

In some examples, an electric machine system including an outer housing; a stator assembly within the outer housing; a corrugated ring located between the stator assembly and the outer housing, the corrugated ring defining a gap between the stator assembly and the outer housing; and a pump configured to transfer a fluid through the gap between the stator assembly and housing to remove heat from at least one of the stator assembly or outer housing.

Claims

1. An electric machine system comprising:

an outer housing;

a stator assembly within the outer housing;

a corrugated ring located between the stator assembly and the outer housing, the corrugated ring defining a gap between the stator assembly and the outer housing; and

a pump configured to transfer a fluid through the gap between the stator assembly and housing to remove heat from at least one of the stator assembly or outer housing.

2. The electric machine system of claim 1, further comprising the fluid, wherein the fluid comprises a liquid.

3. The electric machine system of claim 1, further comprising the fluid, wherein the fluid comprises at least one of water, oil, ethylene glycol, polyalphaolefin, or propylene glycol.

4. The electric machine system of claim 1, further comprising a heat exchanger external to the housing, wherein the pump is configured to transfer the fluid through the heat exchanger from the gap between the stator assembly and the housing, and wherein the heat exchanger is configured to remove heat from the fluid.

5. The electric machine system of claim 1, wherein the gap between the stator assembly and the housing is from approximately 0.040 inches to approximately 0.500 inches.

6. The electric machine system of claim 1, wherein the corrugated ring comprises a plurality of corrugated rings, where respective rings of the plurality of corrugated rings are spaced apart from each other in an axial direction of the stator assembly.

7. The electric machine system of claim 1, wherein the corrugated ring extends only partially around the stator assembly between the stator assembly and housing, further comprising a key connecting a first end and a second end of the corrugated ring around the stator assembly, wherein the key is configured to transfer a torque force from the stator assembly to the housing.

8. The electric machine of claim 1, further comprising control circuitry configured to control a rate at which the pump transfers the fluid through the gap between housing and the stator assembly.

9. The electric machine of claim 1, wherein a rate at which the pump transfers the fluid through the gap between the housing and the stator assembly varies to vary an amount of heat removed from the stator assembly.

10. The electric machine system of claim 1, wherein the electric machine comprises at least one of an electric generator configured to generate electrical energy from mechanical energy or an electric motor configured generate mechanical energy from electrical energy.

11. A method comprising transferring a fluid through a gap between a stator assembly and an outer housing of an electric machine, the fluid being transferred to remove heat from at least one of the stator assembly or housing, wherein the electric machine includes:

the outer housing,

the stator assembly within the outer housing, and

a corrugated ring located between the stator assembly and the outer housing, the corrugated ring defining a gap between the stator assembly and the outer housing.

12. The method of claim 11, wherein the fluid comprises a liquid.

13. The method of claim 11, wherein the fluid comprises at least one of water, oil, or propylene glycol.

14. The method of claim 11, wherein the electric machine includes a heat exchanger external to the housing, wherein the pump is configured to transfer the fluid through the heat exchanger from the gap between the stator assembly and the housing, and wherein the heat exchanger is configured to remove heat from the fluid.

15. The method of claim 11, wherein the gap between the stator assembly and the housing is from approximately 0.040 inches to approximately 0.500 inches.

16. The method of claim 11, wherein the corrugated ring comprises a plurality of corrugated rings, where respective rings of the plurality of corrugated rings are spaced apart from each other in an axial direction of the stator assembly.

17. The method of claim 11, wherein the corrugated ring extends only partially around the stator assembly between the stator assembly and housing, further comprising a key connecting a first end and a second end of the corrugated ring around the stator assembly, wherein the key is configured to transfer a torque force from the stator assembly to the housing.

18. The method of claim 11, further comprising controlling, via control circuitry, a rate at which the pump transfers the fluid through the gap between housing and the stator assembly.

19. The method of claim 11, further comprising varying a rate at which the pump transfers the fluid through the gap between the housing and the stator assembly to vary an amount of heat removed from the stator assembly.

20. The method of claim 11, wherein the electric machine comprises at least one of an electric generator configured to generate electrical energy from mechanical energy or an electric motor configured generate mechanical energy from electrical energy.