Electric motor waste heat mode to heat battery

Patent metadata

Field	Value
Publication number	US-10587162-B2
Application number	US-201715827506-A
Country	US
Kind code	B2
Filing date	Nov 30, 2017
Priority date	Jun 7, 2016
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

An electric motor includes a case, a stator that includes end-windings, a rotor coupled to the case via at least one rotor bearing, at least one drive motor fluid pump, and drive motor electronics. The rotor includes a hollow cylindrical body, a first shaft portion, and a second shaft portion, a fluid feed tube having a fluid receive end and a fluid feed end, the fluid feed end extending into the hollow cylindrical body, and a plurality of fluid exit ports. The drive motor electronics power the stator with or without causing rotation of the rotor. The drive motor fluid pump pumps fluid into the hollow cylindrical body via the fluid feed tube, pumps the fluid out of the plurality of fluid ports, and onto the stator end-windings to collect heat from the rotor and the stator. The heated fluid may be used for heating a battery.

First claim

The invention claimed is:

1. An electric motor comprising:
a case;
a stator that includes a stator lamination and end-windings; and
a rotor coupled to the case via at least one rotor bearing, the rotor comprising:
a hollow cylindrical body having an inner wall, an outer wall, a first distal end, and a second distal end;
a first shaft portion coupled to the first distal end of the hollow cylindrical body;
a second shaft portion coupled to the second distal end of the hollow cylindrical body;
a fluid feed tube having a fluid receive end and a fluid feed end, the fluid feed end extending into the hollow cylindrical body; and
a plurality of fluid exit ports;

at least one drive motor fluid pump to pump fluid into the fluid receive end of the fluid feed tube; and
drive motor electronics, wherein in a waste heat mode:
the drive motor electronics power the stator with or without causing rotation of the rotor;
the drive motor fluid pump at least partially fills the hollow cylindrical body with the fluid to force the fluid from the hollow cylindrical body to collect heat from the stator end-windings; and
the drive motor fluid pump circulates the fluid to a heat exchanger for heating a battery.

2. The electric motor of claim 1 , wherein the second shaft portion includes the fluid feed tube formed therein.

3. The electric motor of claim 1 , further comprising fluid circulation piping having:
an output portion coupled between the drive motor fluid pump output and the fluid receive end of the second shaft portion; and
an input portion coupled between a fluid collection point on the case and the drive motor fluid pump input.

4. The electric motor of claim 1 , further comprising a radiator configured to cool the fluid.

5. The electric motor of claim 4 , further comprising a heat exchanger coupled between the drive motor fluid pump and the radiator.

6. The electric motor of claim 1 , wherein the fluid feed end of the fluid feed tube comprises a plurality of fluid spray ports configured to spray fluid onto the inner wall of the hollow cylindrical body.

7. The electric motor of claim 1 , further comprising an oil distribution ring coupled to the rotor and configured to deflect fluid from the plurality of fluid exit ports to at least one of the stator end-windings or the stator lamination.

8. An electric motor comprising:
a case;
a stator that includes end-windings; and
a rotor coupled to the case via at least one rotor bearing, the rotor comprising:
a hollow cylindrical body, a first shaft portion, and a second shaft portion;
a fluid feed tube having a fluid receive end and a fluid feed end, the fluid feed end extending into the hollow cylindrical body; and
a plurality of fluid exit ports forming corresponding passages between an interior of the hollow cylindrical body and an exterior of the hollow cylindrical body;

at least one drive motor fluid pump to pump fluid into the fluid receive end of the fluid feed tube; and
drive motor electronics, wherein in a waste heat mode:
the drive motor electronics power the stator with or without causing rotation of the rotor;
the drive motor fluid pump circulates fluid into the hollow cylindrical body via the fluid feed tube, out of the plurality of fluid ports, and onto the stator end-windings to collect heat from the rotor and the stator; and
the drive motor fluid pump circulates the fluid to a heat exchanger for heating a battery.

9. The electric motor of claim 8 , wherein the second shaft portion includes the fluid feed tube formed therein.

10. The electric motor of claim 9 , wherein the fluid feed tube is oriented along an axis of rotation of the rotor.

11. The electric motor of claim 8 , further comprising fluid circulation piping having:
an output portion coupled between the drive motor fluid pump output and the fluid receive end of the second shaft portion; and
an input portion coupled between a fluid collection point on the case and the drive motor fluid pump input.

12. The electric motor of claim 8 , further comprising a radiator configured to cool the fluid.

13. The electric motor of claim 12 , further comprising a heat exchanger coupled between the drive motor fluid pump and the radiator.

14. The electric motor of claim 8 , wherein the fluid feed end of the fluid feed tube comprises a plurality of fluid spray ports configured to spray fluid into the hollow cylindrical body.

15. The electric motor of claim 8 , further comprising an oil distribution ring coupled to the rotor and configured to deflect fluid from the plurality of fluid exit ports to at least one of the stator end-windings or the stator lamination.

16. A method for operating an electric motor comprising:
powering a stator of the electric motor to heat end-windings of the stator with or without causing a rotor of the electric motor to rotate;
pumping fluid into a hollow cylindrical body of the rotor via a fluid feed tube, out of the hollow cylindrical body of the rotor via a plurality of fluid exit ports, and the end-windings of the stator to collect heat from at least the end-windings of the stator to produce heated fluid; and
pumping the heated fluid to a heat exchanger for heating a battery.

17. The method of claim 16 , wherein the fluid feed tube that is oriented along an axis of rotation of the rotor.

18. The method of claim 16 , wherein pumping the fluid into the hollow cylindrical body includes spraying the fluid from the fluid feed tube onto an inner wall of the hollow cylindrical body of the rotor.

19. The method of claim 18 , wherein spraying the fluid from the fluid feed tube includes spraying the fluid onto a central portion of the inner wall of the hollow cylindrical body.

20. The method of claim 16 , further comprising circulating coolant between the heat exchanger and the battery, wherein the coolant is heated by the heated fluid in the heat exchanger.

Assignees

• Tesla Inc

Inventors

• Yang Bozhi
• Martins Tomas Vianna
• Graves Scott Michael
• Swint Ethan
• Bellemare Eric
• Fedoseyev Lev
• Dellal Benjamin
• Olsen Leif E
• Hain Alexander

Classifications

• H02K1/32 Primary

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

• H02K3/12

  arranged in slots · CPC title

• H02K9/193

  with provision for replenishing the cooling medium; with means for preventing leakage of the cooling medium · CPC title

• H02K5/16

  Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields (magnetic bearings H02K7/09) · CPC title

• H02K1/274

  the rotor consisting of two or more circumferentially positioned magnets · CPC title