COOLING ARRANGEMENT FOR AN ELECTRIC MACHINE

• US 20120274159A1
• Filed: 04/25/2012
• Published: 11/01/2012
• Est. Priority Date: 04/27/2011
• Status: Active Grant

• Current Assignee: Siemens Gamesa Renewable Energy A/S (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Le Besnerais, Jean
• Granted Patent: US 8,866,351 B2
• Time in Patent Office: Days
• US Class Current: 310/54
• CPC Class Codes: H02K 1/20 with channels or ducts for flow of cooling medium
• CPC Class Codes: H02K 7/1838 Generators mounted in a nacelle or similar structure of a horizontal axis wind turbine
• CPC Class Codes: H02K 9/10 by gaseous cooling medium flowing in closed circuit, a part of which is external to the machine casing
• 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: H02K 9/227 Heat sinks
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction

Abstract

The electric machine includes a stator. The stator includes stacked lamination plates. The lamination plates form at least two lamination packages. The electric machine includes a first cooling circulation with a first cooling fluid. The stator of the electric machine includes a second cooling circulation with a second cooling fluid. A heat exchanger is part of the second cooling circulation and is arranged to connect the first cooling circulation and the second cooling circulation. Thus heat is transferred from the first cooling fluid to the second cooling fluid. A spacer element is arranged between the two lamination packages. The spacer element is prepared to set a predetermined distance between the lamination packages, thus the first cooling fluid is allowed to flow between the lamination packages. The heat exchanger arrangement is an integral or at least partly integrated part of the spacer elements.

Claims

1. A cooling arrangement for an electric machine

wherein the electric machine comprises a stator,

wherein the stator comprises stacked lamination plates,

wherein the lamination plates form at least two lamination packages,

wherein the electric machine comprises a first cooling circulation with a first cooling fluid,

wherein the stator of the electric machine comprises a second cooling circulation with a second cooling fluid,

wherein a spacer element is arranged between the two lamination packages, the spacer element configured to set a predetermined distance between the lamination packages, thus the first cooling fluid is allowed to flow between the lamination packages, and

wherein a heat exchanger which is an integral part of the spacer elements is arranged to connect the first cooling circulation and the second cooling circulation to transfer heat from the first cooling fluid to the second cooling fluid.

2. The cooling arrangement according to claim 1,

wherein the lamination plates comprise a gap,

wherein the gap is prepared to support a winding of a coil, and

wherein the winding extends over the lamination packages in longitudinal direction of the stator to form a winding overhang.

3. The cooling arrangement according to claim 1,

wherein the heat exchanger comprises plurality of heat exchanger elements.

4. The cooling arrangement according to claim 3,

wherein the heat exchanger elements include a duct for the second fluid.

5. The cooling arrangement according to claim 4,

wherein the surface of the heat exchanger element is enlarged to provide an increased heat-transfer.

6. The cooling arrangement according to claim 5,

wherein the enlarged is a fin-shaped enlargement.

7. The cooling arrangement according to claim 1,

wherein the lamination plates comprise at least one opening thereby forming a continuous duct within the lamination package.

8. The cooling arrangement according to claim 1,

wherein the duct of the lamination package is connected with the duct in the heat exchanger element thereby guiding the second fluid through the lamination package the heat exchanger element.

9. The cooling arrangement according to claim 1,

wherein a pipe is arranged within the duct of the lamination package and within the duct of the heat exchanger element to guide the second fluid.

10. The cooling arrangement according to claim 1,

wherein a number of lamination packages are arranged in a way that they form at least a sector of the stator,

wherein the sector is supported by at least two plates, and

wherein the second fluid is guided through the plates into the ducts or pipes in the lamination packages.

11. The cooling arrangement according to claim 1,

wherein the at least two plates are finger plates.

12. The cooling arrangement according to claim 1,

wherein the second fluid is a liquid.

13. The cooling arrangement according to claim 1,

wherein the first fluid is a gas.

14. The cooling arrangement according to claim 13

wherein the electric machine comprises a rotor with an air gap between the rotor and the stator, and

wherein the first cooling circulation is arranged to direct the gas through the winding overhang, through the air gap and along the heat exchanger elements, thereby the gas cools the winding overhang and the surface of the rotor and the stator adjacent to the air gap and transfers the thermal energy to the second cooling circulation by passing the heat exchanger elements.

15. The cooling arrangement according to claim 1, wherein the electrical machine is a generator.

16. The cooling arrangement according to claim 1, wherein the electrical machine is a wind turbine generator.