Method And System For Controlling Operation Of An Electric Oil Pump In A Hybrid Electric Vehicle (HEV)

• US 20110166727A1
• Filed: 08/30/2010
• Published: 07/07/2011
• Est. Priority Date: 08/30/2010
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Kozarekar, Shailesh Shrikant, Light, Brian Richard, Wu, Wei
• Granted Patent: US 8,649,925 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 2240/485 Temperature
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2510/107 Temperature
• CPC Class Codes: B60W 30/18018 Start-stop drive, e.g. in a traffic jam
• CPC Class Codes: F16H 57/0441 Arrangements of pumps
• CPC Class Codes: F16H 61/0031 using auxiliary pumps, e.g. pump driven by a different power source than the engine
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A system and method is provided for controlling operation of an electric oil pump in a hybrid electric vehicle (HEV). The HEV includes an engine and a transaxle including an electric motor coupled to a traction battery. A commanded speed for the electric oil pump is determined and whether the engine in the HEV is in an off state is determined. When the engine is in the off state, the electric oil pump is controlled to operate at the commanded speed.

Claims

1. A method of controlling operation of an electric oil pump in a hybrid electric vehicle (HEV) with an engine and a transaxle with an electric motor, the method comprising:

controlling the electric oil pump to operate at a commanded speed when the engine is in an off state.

2. The method of claim 1 further including determining a pump operating time and controlling the electric oil pump to operate at the commanded speed for the determined time.

3. The method of claim 1 further including determining an operating condition of the HEV and determining the commanded speed based on the operating condition of the HEV.

4. The method of claim 3 further including determining the operating condition of the HEV based on whether the HEV is operating in an electric drive mode.

5. The method of claim 3 further including determining the operating condition of the HEV based on a noise, vibration, and harshness (NVH) level in the HEV.

6. The method of claim 3 further including determining an electric oil pump operating time based on the operating condition of the HEV and controlling the electric oil pump to operate at the commanded speed for the determined time.

7. The method of claim 1 further including determining a prior operating mode of the HEV and determining the commanded speed based on the prior operating mode.

8. The method of claim 7 further including determining a pump operating time based on the prior operating mode of the HEV and controlling the electric oil pump to operate at the commanded speed for the pump operating time.

9. The method of claim 7 further including determining the prior operating mode based on at least one of a prior speed of the HEV and a torque output in the HEV.

10. The method of claim 1 further including calculating a power loss in the HEV and determining the commanded speed based on the power loss.

11. The method of claim 10 wherein the power loss is calculated based on an estimated power loss from at least one of a motor in the transaxle, a generator in the transaxle, and an electronic power converter in the HEV.

12. The method of claim 10 further including determining a pump operating time based on the power loss in the HEV and controlling the electric oil pump to operate at the commanded speed for the operating time.

13. The method of claim 1 further including obtaining at least one temperature level and determining the commanded speed based on the temperature level.

14. The method of claim 13 wherein the temperature level indicates a temperature of at least one of, a motor in the transaxle, a generator in the transaxle, transaxle oil in the HEV, and ambient air outboard of the HEV.

15. The method of claim 13 further including determining a pump operating time based on the temperature level in the HEV and controlling the electric oil pump to operate at the commanded speed for the operating time.

16. The method of claim 1 further including determining an operating condition of the HEV and at least one temperature level, and determining the commanded speed based on the temperature level and the operating condition of the HEV.

17. The method of claim 1 wherein controlling the electric oil pump includes providing transaxle oil to lubricate and cool components in the transaxle.

18. A system for controlling operation of an electric oil pump in a hybrid electric vehicle (HEV) with an engine and a transaxle including an electric motor coupled to a traction battery, the system comprising:

at least one logic device configured to determine whether the engine in the HEV is in an off state and a commanded speed for the electric oil pump, and to control the electric oil pump to operate at the commanded speed when the engine is in the off state.

19. The system of claim 18 wherein the logic device is a controller including a processor operable to execute software instructions, a computer memory operable to store software instructions accessible by the processor, and a set of software instructions stored in the memory to determine the commanded speed for the electric oil pump and to control the electric oil pump to operate at the commanded speed when the engine is in the off state.

20. At least one logic storage medium having logic-device-readable code embodied thereon for performing a method of controlling operation of an electric oil pump in a hybrid electric vehicle (HEV) with an engine and a transaxle including an electric motor coupled to a traction battery, the method comprising:

controlling the electric oil pump to operate at a commanded speed when the engine is in an off state.