Electric motor waste heat mode to heat battery

• US 10,587,162 B2
• Filed: 11/30/2017
• Issued: 03/10/2020
• Est. Priority Date: 06/07/2016
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Inc.
• Inventors: Yang, Bozhi, Martins, Tomas Vianna, Graves, Scott Michael, Swint, Ethan, Bellemare, Eric, Fedoseyev, Lev, Dellal, Benjamin, Olsen, Leif E., Hain, Alexander
• Primary Examiner(s): Nguyen, Tran N
• Application Number:
  US15/827,506
• Publication Number:
  US 20180083509A1
• Time in Patent Office: 831 Days
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/6567 Liquids
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02K 1/16 Stator cores with slots for windings
• CPC Class Codes: H02K 1/274 the rotor consisting of two or more circumferentially positioned magnets
• CPC Class Codes: H02K 1/32 with channels or ducts for flow of cooling medium
• CPC Class Codes: H02K 11/00 Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection casings, enclosures or supports H02K5/00
• CPC Class Codes: H02K 11/40 Structural association with grounding devices
• CPC Class Codes: H02K 3/12 arranged in slots
• CPC Class Codes: H02K 5/16 Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields magnetic bearings H02K7/09
• CPC Class Codes: H02K 5/1732 radially supporting the rotary shaft at both ends of the rotor H02K5/1737 takes precedence
• CPC Class Codes: H02K 7/003 Couplings; Details of shafts means for mounting rotors on shafts H02K1/28
• CPC Class Codes: H02K 7/083 radially supporting the rotary shaft at both ends of the rotor H02K7/086, H02K7/09 take precedence
• CPC Class Codes: H02K 9/193 with provision for replenishing the cooling medium; with means for preventing leakage of the cooling medium
• 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: H02P 29/62 for raising the temperature of the motor
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

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.

Claims

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.