Dynamic Allocation of Drive Torque

• US 20080308066A1
• Filed: 06/13/2007
• Published: 12/18/2008
• Est. Priority Date: 06/13/2007
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Martin, Douglas Raymond, Gartner, Paul M., Badillo, Ed
• Granted Patent: US 7,967,720 B2
• Time in Patent Office: Days
• US Class Current: 123/403
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/06 including control of combustion engines
• 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 20/40 Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers power-up or power-down of the driveline B60W30/192
• CPC Class Codes: B60W 2510/06 Combustion engines, Gas turbines
• CPC Class Codes: B60W 2510/08 Electric propulsion units
• CPC Class Codes: B60W 2710/0622 Air-fuel ratio
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 41/0042 Controlling the combustible mixture as a function of the canister purging, e.g. control of injected fuel to compensate for deviation of air fuel ratio when purging
• CPC Class Codes: F02D 41/1497 With detection of the mechanical response of the engine
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A method for operating a powertrain in a vehicle is provided. The powertrain includes an electric drive and an internal combustion engine. The method comprises providing torque to drive the vehicle from both the electric drive and the engine, where engine torque is varied within an allowable range; and when operating the engine at an edge of the range, adjusting the range based on whether a selected operating condition can be provided by the engine.

Claims

1. A method for operating a powertrain in a vehicle, the powertrain including an electric drive and an internal combustion engine, the method comprising:

providing torque to drive the vehicle from both the electric drive and the engine, where engine torque is varied within an allowable range; and

when operating the engine at an edge of the range, adjusting the range based on whether a selected operating condition can be provided by the engine.

2. The method of claim 1, further comprising limiting an engine torque commanded by a vehicle system controller to an engine controller to be within the adjusted range and compensating limitation of engine torque by increasing torque from the electric drive to meet a driver request.

3. The method of claim 2, further comprising suspending the adjusting of the range if operating near wide open pedal conditions, where the selected operating condition is engine torque.

4. The method of claim 3, further comprising suspending the adjusting of the range based on engine torque if purging more than a selected amount or concentration of fuel vapors into the engine from a fuel system, and adjusting the range based on whether a vacuum amount is provided.

5. The method of claim 4, wherein the selected concentration of fuel vapors is a predetermined fuel vapor concentration determined based on fuel injector adjustment during purging operation.

6. The method of claim 5, wherein the range is adjusted based on whether a desired engine torque is achieved with wide-open throttle operation.

7. The method of claim 1, wherein the range is adjusted based on whether a desired engine torque is achieved with wide-open throttle operation.

8. The method of claim 1, wherein adjusting of the range is suspended when operating away from an end of the range.

9. The method of claim 8, further comprising adaptively learning the adjustment in keep alive memory of a controller.

10. The system of claim 9, wherein the engine drive command is an engine torque.

11. The system of claim 10, wherein the maximum engine torque is reduced due to restricted airflow into the engine.

12. The system of claim 10, wherein the electric drive is a motor coupled to wheels of the vehicle.

13. The system of claim 12, wherein adjusting of the range is suspended if operating near wide open pedal conditions.

14. The system of claim 12, wherein adjusting of the range is suspended if purging more than a selected amount or concentration of fuel vapors into the engine from a fuel system, where the range is adjusted based on whether a vacuum amount is provided.

15. The system of claim 14, wherein the range is adjusted based on whether a desired engine torque is achieved with wide-open throttle operation.

16. The system of claim 9, wherein the range is adjusted based on whether a desired engine torque is achieved with wide-open throttle operation.

9-1. A system for a hybrid vehicle having a powertrain including an electric drive and an internal combustion engine, comprising:

a vehicle system controller, the vehicle system controller adjusting drive allocation between the electric drive and the internal combustion engine based on operating conditions, where the vehicle system controller generates an engine drive command and transmits the engine drive command to an engine controller, where the engine drive command is varied within an allowable range; and

the engine controller, the engine controller receiving the engine drive command from the vehicle system controller and adjusting engine output responsive to the engine drive command, where when operating at the engine at an edge of the range, the range is adjusted based on whether a selected operating condition can be provided by the engine so that as the maximum engine torque of the engine is reduced, the vehicle system controller reduces the allowable range and adjusts the electric drive to compensate for the reduction in the allowable range of the engine.

17. A method to operate an internal combustion engine in a vehicle, the vehicle including a vehicle system controller configured to determine an estimated maximum allowed torque, and to control the internal combustion engine, the method comprising:

receiving the estimated maximum allowed torque from the vehicle system controller;

determining a torque adjustment value;

varying the torque adjustment value based on the estimated maximum allowed torque and an actual torque produced by the engine; and

adjusting the estimated maximum allowed torque according to the torque adjustment value.

18. The method of claim 17, further comprising:

controlling the internal combustion engine based on the adjusted maximum allowed torque.

19. The method of claim 18, wherein adjusting the estimated maximum allowed torque includes adding the torque adjustment value to the estimated maximum allowed torque.

20. The method of claim 19, wherein varying the torque adjustment value includes decreasing the torque adjustment value by a predetermined increment if the actual torque is less than the estimated maximum allowed torque and increasing the torque adjustment value by the predetermined increment if the actual torque is greater than the estimated maximum allowed torque.