Electric machine with improved cooling

Patent metadata

Field	Value
Publication number	US-9806586-B2
Application number	US-201515325353-A
Country	US
Kind code	B2
Filing date	Jun 29, 2015
Priority date	Jul 14, 2014
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

An electric machine includes a housing having a first hollow cylinder-shaped housing element for guidance of a first cooling medium in a first axial direction, and a second hollow cylinder-shaped housing element in which the first housing element is arranged. Arranged in the first housing element is a hollow cylinder-shaped stator and a rotor which is mounted in the stator for rotation about a rotational axis. A heat exchanger cover is arranged between the first and second housing elements and includes a guide element running helically about the rotational axis, and pipes extending axially and passing through the guide element. The heat exchanger cover guides the first cooling medium between the pipes in a helical manner along the at least one guide element in a second axial direction which runs opposite to the first axial direction, and guides a second cooling medium through the pipes in an axial direction.

First claim

What is claimed is:

1. An electric machine, comprising:
a housing including a first hollow cylinder-shaped housing element having at least one section for guidance of a first cooling medium in a first axial direction, and a second hollow cylinder-shaped housing element in which the first hollow cylinder-shaped housing element is arranged;
a hollow cylinder-shaped stator arranged in the first hollow cylinder-shaped housing element;
a rotor arranged in the first hollow cylinder-shaped housing element and mounted in the stator for rotation about a rotational axis; and
a heat exchanger cover arranged between the first housing element and the second housing element, said heat exchanger cover including at least one guide element which runs helically about the rotational axis, and pipes which extend axially and pass through the at least one guide element, said heat exchanger cover having at least one section for guidance of the first cooling medium between the pipes in a helical manner along the at least one guide element in a second axial direction which runs opposite to the first axial direction, said heat exchanger cover having at least one section for guidance of a second cooling medium through the pipes in an axial direction.

2. The electric machine of claim 1 , wherein the at least one guide element is configured to define a helical path having a pitch angle of at most 60°.

3. The electric machine of claim 1 , wherein the at least one guide element is configured to define a helical path having a pitch angle between 10° to 30°.

4. The electric machine of claim 1 , wherein the first cooling medium is separated from the second cooling medium in a fluid-tight manner.

5. The electric machine of claim 1 , wherein the stator includes a stator active part, winding heads respectively projecting from the stator active part at first and second axial front ends, and stator cooling ducts which open radially outwards at a plurality of axial positions, said rotor including a rotor active part, at least one rotor opening at a first axial front end, and rotor cooling ducts which are connected to the rotor opening and open radially outwards at a plurality of axial positions, said stator and said first, housing element define there between at least one recess for guidance of the first cooling medium in the axial direction.

6. The electric machine of claim 5 , further comprising at least one first guide apparatus at one of the first and second axial front ends for routing the first cooling medium from the heat exchanger cover to the at least one rotor opening and to an adjacent one of the winding heads.

7. The electric machine of claim 5 , further comprising:
a first turbo-machine for recirculating the first cooling medium; and
at least one second guide apparatus at another one of the first and second axial front ends for routing the first cooling medium from an adjacent one of the winding heads to the first turbo-machine and from the first turbo-machine to the heat exchanger cover.

8. The electric machine of claim 5 , further comprising:
two first turbo-machines for recirculating the first cooling medium; and
third guide apparatuses respectively arranged at the first and second axial front ends for routing the first cooling medium from the heat exchanger cover to the first turbo-machines and from the first turbo-machines to the rotor opening and a further rotor opening at a second axial front end and to the winding heads.

9. The electric machine of claim 1 , wherein the first housing element has at least one passage in a region of its axial center for guidance of the first cooling medium from within the first housing element into the heat exchanger cover.

10. The electric machine of claim 1 , wherein the housing has at least one first housing opening and at least one second housing opening for inflow and outflow of the second cooling medium, and further comprising a turbo-machine for recirculating the second cooling medium, said turbo-machine and the pipes of the heat exchanger cover being arranged between the first housing opening and the second housing opening.

11. The electric machine of claim 10 , wherein the at least one first housing opening is arranged in a region of a first axial front end and the at least one second housing opening is arranged in a region of a second axial front end.

12. The electric machine of claim 10 , wherein the at least one first housing opening is arranged in a region of a first axial front end and the at least one second housing opening is arranged in a region of an axial center.

13. The electric machine of claim 1 , constructed for operation with an electrical power of at least 1 MW.

14. The electric machine of claim 1 , constructed for operation with an electrical power of more than 3 MW.

15. The electric machine of claim 1 , having an axial height of at least 500 mm.

16. The electric machine of claim 15 , constructed in the form of a generator, a drive motor for a pump drive, a compressor drive, or a steelwork drive.

17. The electric machine of claim 15 , constructed in the form of a wind power generator.

18. The electric machine of claim 1 , having an axial height of at least 630 mm.

Assignees

• Siemens Ag

Inventors

• Granat Gerd
• Putz Walter

Classifications

• H02K1/32

  with channels or ducts for flow of cooling medium · CPC title

• H02K9/18 Primary

  wherein the external part of the closed circuit comprises a heat exchanger structurally associated with the machine casing · CPC title

• H02K1/20

  with channels or ducts for flow of cooling medium · CPC title