Axially extending electric machine electronics cooling tower

Patent metadata

Field	Value
Publication number	US-10389211-B2
Application number	US-201514876821-A
Country	US
Kind code	B2
Filing date	Oct 7, 2015
Priority date	Oct 8, 2014
Publication date	Aug 20, 2019
Grant date	Aug 20, 2019

Abstract

An electronic package adapted for connection to a rear frame member of an electric machine. The electronic package includes a cooling tower having first and second axial ends. The cooling tower includes a metallic wall defining radially inner and outer wall surfaces and extending about the package central axis. The radially inner wall surface defines an axially extending air passage through the cooling tower with an inlet proximate the first axial end. Spaced metallic ribs are in conductive thermal communication with the radially inner wall surface traverse and the air passage. Power electronics devices are attached in conductive thermal communication to the radially outer wall surface. The cooling tower provides a heat sink for the power electronics devices with a primary cooling path for each of the power electronics device extending radially inwardly to the cooling tower. An electric machine including such an electronic package is also disclosed.

First claim

What is claimed is:

1. An electronic package adapted for connection to a rear frame member of an electric machine, the electronic package comprising:
a cooling tower having opposite first and second axial ends spaced along a package central axis, the cooling tower comprising:
a metallic wall circumscribing the package central axis to define a radially inner wall surface and a radially outer wall surface, the radially inner wall surface defining an axially extending air passage through the cooling tower, the air passage having an inlet proximate the first axial end and an outlet proximate the second axial end, and
a plurality of spaced metallic ribs in conductive thermal communication with the radially inner wall surface and extending radially inwardly into the axially extending air passage, and wherein the ribs extend axially within the air passage from proximate the inlet to proximate the outlet; and

a plurality of power electronics devices attached in conductive thermal communication to the cooling tower at circumferentially distributed positions on the radially outer wall surface;
wherein the cooling tower provides a heat sink for heat loss from the power electronics devices, and a primary cooling path for each power electronics device extends radially inwardly to the cooling tower therefrom;
wherein each of the plurality of power electronics devices is incorporated into a power module, each power module further comprising:
a base disposed radially outwardly of the metallic wall and in conductive thermal communication with the radially outer wall surface, and
a metallic cover plate, the cover plate having an interior surface superposing the base, the interior surface being spaced from and positioned in close proximity to the power electronics device of the respective power module and an exterior surface disposed radially outwardly of and exterior to the axially extending air passage and oriented radially outward and unobstructedly exposed to ambient air exterior to the axially extending air passage and surrounding the electronic package and wherein the cover plate directly engages and is in conductive thermal communication with the base or the radially outer wall surface at a location spaced from and positioned in close proximity to the power electronics device;
wherein the power electronic device of each of the power modules is positioned between the base and the interior surface of the cover plate of each respective power module;

wherein heat loss from each power module is transferred along the primary cooling path radially inwardly through the base and metallic wall to one or more of the plurality of spaced metallic ribs within the axially extending air passage and along a secondary cooling path extending radially outwardly through the cover plate and to ambient air exterior to axially extending air passage whereby the cover plate acts as a heat sink which absorbs heat from the power electronic device through surfaces exposed to the air surrounding the power electronic device and through the direct engagement of the cover plate with the base or the radially outer wall surface.

2. The electronic package of claim 1 , wherein the module cover plates are configured with fins, whereby convective heat transfer therefrom is enhanced.

3. The electronic package of claim 1 , wherein the base defines a surface that abuttingly engages the radially outer wall surface, whereby the base and the cooling tower wall are in conductive thermal communication, the engaging surfaces extending substantially parallel with the package central axis.

4. The electronic package of claim 3 , wherein the plurality of metallic ribs extend directly from circumferential locations on the radially inner wall surface that are directly radially inward of the power modules.

5. The electronic package of claim 3 , wherein the radially outer wall surface defines a plurality of planar mounting surfaces, each planar mounting surface engaging the base surface of a respective power module, each planar mounting surface parallel with the package central axis.

6. The electronic package of claim 5 , wherein each planar mounting surface is oriented tangentially relative to an imaginary circle concentric with and oriented perpendicularly relative to the package central axis.

7. The electronic package of claim 1 , wherein the wall and the ribs are integrally formed portions of the cooling tower.

8. The electronic package of claim 1 , further comprising electronic control circuitry operatively connected to the power electronics devices, the electronic control circuitry substantially surrounded by the plurality of power electronics devices.

9. The electronic package of claim 8 , wherein the control circuitry is substantially thermally isolated from the heat loss from the power electronics devices.

10. The electronic package of claim 1 , wherein the power electronics devices are substantially evenly distributed about the radially outer wall surface.

11. The electronic package of claim 1 , wherein the power electronics devices are equidistance along the package central axis from an imaginary plane perpendicular to the package central axis.

12. An electric machine comprising a stator, a rotor defining a machine central axis and surrounded by and rotatable relative to the stator about the machine central axis, a rear frame member rotatably fixed relative to the stator and through which the machine central axis extends, and
an electronic package according to claim 1 ,
wherein the machine central axis extends through the electronic package and the cooling tower is connected to the rear frame member;
wherein the electric machine is air-cooled and the rear frame member has an aperture through which cooling air flow is drawn generally axially, in the direction of the rotor relative to the electronic package, for cooling the electric machine at locations downstream of the aperture,
wherein the air passage outlet proximate the second axial end is in fluid communication with the rear frame member aperture, and
wherein cooling air flow is drawn into the air passage inlet and through the air passage, convective heat transfer along the primary cooling path occurs between the cooling tower wall and ribs and the cooling air flow along the air passage, and the cooling air flow proceeds through the air passage outlet and the rear frame member aperture for cooling the electric machine at locations downstream of the aperture.

13. The electric machine of claim 12 , wherein the machine central axis and the package central axis coincide.

14. The electric machine of claim 12 , further comprising a fan rotatable with the rotor about the central axis, wherein the air flow through the aperture is induced by fan rotation.

15. The electric machine of claim 12 , wherein the cover plate further comprises at least one boss projecting from the interior surface of the cover plate wherein the boss is in conductive thermal communication with the base at a location spaced from and in close proximity to the power electronics device of the respective power module, the power electronics device of each power module being mounted on a substantially planar surface of the base wherein the interior surface of the cover plate is a substantially planar surface positioned parallel to and spaced from the planar surface of the base.

16. The electric machine of claim 15 , wherein the module cover plates are configured with fins projecting radially outwardly from the cover plates, whereby convective heat transfer therefrom to the ambient air exterior to the axially extending air passage is enh

Assignees

• Remy Tech Llc
• Borgwarner Inc

Inventors

• Bradfield Michael D

Classifications

• H02K5/203

  specially adapted for liquids, e.g. cooling jackets · CPC title

• H02K9/06 Primary

  with fans or impellers driven by the machine shaft · CPC title

• H02K2213/12

  Machines characterised by the modularity of some components · CPC title

• H05K7/20418 Primary

  the radiating structures being additional and fastened onto the housing · CPC title

• H02K5/18

  with ribs or fins for improving heat transfer · CPC title