Heat conductor for use with an inverter in an electric vehicle (EV) or a hybrid-electric vehicle (HEV)

• US 9,076,593 B2
• Filed: 12/29/2011
• Issued: 07/07/2015
• Est. Priority Date: 12/29/2011
• Status: Active Grant

• Current Assignee: Lear Corporation
• Original Assignee: Lear Corporation
• Inventors: Sharaf, Nadir, Pavlovic, Slobodan, Daftuar, Dilip, Ansari, Ajmal
• Primary Examiner(s): Sinclair, David M
• Application Number:
  US13/339,762
• Publication Number:
  US 20130170269A1
• Time in Patent Office: 1,286 Days
• Field of Search: 361/329, 361/328, 361/323
• US Class Current: 1/1
• CPC Class Codes: H01G 2/08 Cooling arrangements; Heating arrangements; Ventilating arrangements
• CPC Class Codes: H02M 7/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H05K 7/209 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20909 takes precedence
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A heat conductor for use with an inverter in an electric or hybrid-electric vehicle, the inverter including a direct current link capacitor having multiple film capacitors configured in a stack to form a substantially polygonal prism. Each film capacitor has orthotropic characteristics. The heat conductor has a first substantially planar member configured to contact a first side of the polygonal prism formed by one of the film capacitors, and a second substantially planar member configured to contact a second side of the polygonal prism opposite the first side of the rectangular prism, the second side of the rectangular prism formed by another one of the film capacitors. The first and second planar member are thermally conductive for dissipating heat generated by the film capacitors, are attached by an interconnect, and have sufficient rigidity to confine expansion of the film capacitors across the thicknesses thereof.

Claims

1. A heat conductor for use with an inverter in an electric vehicle (EV) or a hybrid-electric vehicle (HEV), the inverter including a direct current (DC) link capacitor comprising a plurality of film capacitors configured in a stack to form a substantially polygonal prism, wherein each film capacitor has orthotropic characteristics such that a thermal conductivity across a thickness of each film capacitor differs from a thermal conductivity across another dimension of the film capacitor, and such that a stiffness across the thickness of each film capacitor is less than a stiffness across another dimension of the film capacitor, the heat conductor comprising:

a first substantially planar member configured to contact a first side of the polygonal prism formed by a single one of the film capacitors, the first substantially planar member comprising a thermally conductive material for dissipating heat generated by the plurality of film capacitors;

a second substantially planar member configured to contact a second side of the polygonal prism opposite the first side of the polygonal prism, the second side of the polygonal prism formed by another single one of the film capacitors, the second substantially planar member comprising a thermally conductive material for dissipating heat generated by the plurality of film capacitors; and

an interconnect for fixedly attaching the first and second substantially planar members, wherein the interconnect comprises a third substantially planar member comprising a thermally conductive material, the third planar member substantially coextensive with a third side of the substantially polygonal prism oriented between the first and second sides of the prism, wherein the third substantially planar member comprises a first piece extending from the first substantially planar member and a second piece extending from the second substantially planar member, the first and second pieces each having an attachment feature, the attachment features of the first and second pieces configured to cooperate for attachment of the first and second pieces, and wherein the attachment features of the first and second pieces are further configured to operate as heat dissipating features by increasing a surface area of the third substantially planar member;

wherein the first and second substantially planar members have sufficient rigidity to confine expansion of the plurality of film capacitors across the thicknesses thereof.

2. The heat conductor of claim 1 wherein the first and second substantially planar members comprise a metal.

3. The heat conductor of claim 1 wherein the first and second substantially planar members are substantially coextensive with the first and second sides of the prism.

4. The heat conductor of claim 3 wherein the first and second substantially planar members are substantially coextensive with the first and second sides of the prism to substantially contain expansion of the film capacitors.

5. The heat conductor of claim 1 wherein the first substantially planar member comprises at least one feature to increase a surface area of the first substantially planar member to facilitate heat dissipation.

6. The heat conductor of claim 1 further comprising a feature configured to attach the first substantially planar member to a cold plate.

7. A heat conductor for use with an inverter in an electric vehicle (EV) or a hybrid-electric vehicle (HEV), the inverter including a direct current (DC) link capacitor comprising a plurality of film capacitors configured in a stack to form a substantially polygonal prism, wherein each film capacitor has orthotropic characteristics such that a thermal conductivity across the thickness of each film capacitor differs from a thermal conductivity across another dimension of the film capacitor, and such that a stiffness across the thickness of each film capacitor is less than a stiffness across another dimension of the film capacitor, the heat conductor comprising:

a first plate configured to contact a first side of the polygonal prism formed by a single one of the film capacitors, the first plate substantially coextensive with the first side of the prism and comprising a thermally conductive material for dissipating heat generated by the plurality of film capacitors;

a second plate configured to contact a second side of the polygonal prism opposite the first side of the polygonal prism, the second side of the prism formed by another single one of the film capacitors, the second plate substantially coextensive with the second side of the prism and comprising a thermally conductive material for dissipating heat generated by the plurality of film capacitors; and

a third plate fixedly connecting the first and second plates, wherein the third plate comprises a thermally conductive material and is substantially coextensive with a third side of the polygonal prism between the first and second sides of the prism, wherein the third plate comprises a first piece extending from the first plate and a second piece extending from the second plate, the first and second pieces each having an attachment feature, the attachment features of the first and second pieces configured to cooperate for attachment of the first and second pieces, wherein the attachment feature of the first and second pieces are further configured to operate as heat dissipating features by increasing the surface area of the third plate;

wherein the first and second plates have sufficient rigidity to confine expansion of the plurality of film capacitors across the thicknesses thereof.

8. The heat conductor of claim 7 wherein the first and second plates comprise a metal.

9. The heat conductor of claim 7 wherein the first plate comprises at least one feature to increase a surface area of the first substantially planar member to facilitate heat dissipation.

10. The heat conductor of claim 7 wherein the first and second plates are substantially coextensive with the first and second sides of the prism to substantially contain expansion of the film capacitors.

11. The heat conductor of claim 7 wherein the third plate comprises a metal.

12. An inverter in an electric vehicle (EV) or a hybrid-electric vehicle (HEV), the inverter comprising:

a direct current (DC) link capacitor comprising a plurality of film capacitors configured in a stack to form a substantially polygonal prism, wherein each film capacitor has orthotropic characteristics such that a thermal conductivity across the thickness of each film capacitor differs from a thermal conductivity across another dimension of the film capacitor, and such that a stiffness across the thickness of each film capacitor is less than a stiffness across another dimension of the film capacitor;

a heat conductor comprising a first substantially planar member configured to contact a first side of the polygonal prism formed by a single one of the film capacitors, and a second substantially planar member configured to contact a second side of the polygonal prism opposite the first side of the polygonal prism, the second side of the prism formed by another single one of the film capacitors, the first and second substantially planar members comprising a thermally conductive material for dissipating heat generated by the plurality of film capacitors; and

an interconnect for fixedly attaching the first and second substantially planar members, wherein the interconnect comprises a third substantially planar member comprising a thermally conductive material, the third planar member substantially coextensive with a third side of the substantially polygonal prism oriented between the first and second sides of the prism, wherein the third substantially planar member comprises a first piece extending from the first substantially planar member and a second piece extending from the second substantially planar member, the first and second pieces each having an attachment feature, the attachment features of the first and second pieces configured to cooperate for attachment of the first and second pieces, and wherein the attachment features of the first and second pieces are further configured to operate as heat dissipating features by increasing a surface area of the third substantially planar member;

wherein the first and second substantially planar members have sufficient rigidity to confine expansion of the plurality of film capacitors across the thicknesses thereof.

13. The inverter of claim 12 further comprising a cold plate for attachment to the heat conductor.