METHOD AND APPARATUS FOR CONTROLLING A HYBRID POWERTRAIN SYSTEM

• US 20090118078A1
• Filed: 10/01/2008
• Published: 05/07/2009
• Est. Priority Date: 11/07/2007
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG, Daimler AG (Mercedes-Benz Group AG), Chrysler Group LLC (Stellantis NV)
• Original Assignee: BMW AG (Bayerische Motoren Werke AG), GM Global Technology Operations Incorporated (General Motors Company), Daimler AG (Mercedes-Benz Group AG), Chrysler LLC (Stellantis NV)
• Inventors: Potter, Mark J., Wilmanowicz, Marek L., Kaufer, Matthew Leonard, Heap, Anthony H., Cawthorne, William R., Bolton, Michael
• Granted Patent: US 8,271,173 B2
• Time in Patent Office: Days
• US Class Current: 477/3
• 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: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• 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 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 2050/0006 Digital architecture hierarchy
• CPC Class Codes: B60W 2510/0619 Air-fuel ratio
• CPC Class Codes: B60W 2510/0628 Inlet air flow rate
• CPC Class Codes: B60W 2510/0671 Engine manifold pressure
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2510/083 Torque
• CPC Class Codes: B60W 2510/105 Output torque
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 : Brake pedal position
• CPC Class Codes: B60W 2540/16 : Ratio selector position
• CPC Class Codes: B60W 2540/215 : Selection or confirmation of options
• CPC Class Codes: B60W 2555/20 : Ambient conditions, e.g. wind or rain
• CPC Class Codes: B60W 2710/0605 : Throttle position
• CPC Class Codes: B60W 2710/0622 : Air-fuel ratio
• CPC Class Codes: B60W 2710/0644 : Engine speed
• CPC Class Codes: B60W 2710/065 : Idle condition
• CPC Class Codes: B60W 2710/0661 : Speed change rate
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/1011 : Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2710/1016 : Input speed change rate
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility

Abstract

A control method for vehicular hybrid powertrain system includes monitoring operator inputs to an accelerator pedal and a transmission gear selector, and determining an operator torque request based upon the operator inputs to the accelerator pedal and the transmission gear selector. Torque output from the electric machine is commanded based upon the operator torque request. Engine output is controlled based upon the operator torque request and the commanded torque output from the electric machine. Vehicle hood position is monitored and the engine output is controlled correlative to the operator input to the accelerator pedal when the monitored position of the vehicle hood is open and the operator input to the transmission gear selector is one of a PARK and a NEUTRAL position.

Claims

1. Control method for a vehicular hybrid powertrain system including an engine and an electric machine selectively operatively coupled to a transmission device to transmit torque therebetween, the method comprising:

monitoring operator inputs to an accelerator pedal and a transmission gear selector;

determining an operator torque request based upon the operator inputs to the accelerator pedal and the transmission gear selector;

commanding a torque output from the electric machine based upon the operator torque request;

controlling engine output based upon the operator torque request and the commanded torque output from the electric machine;

monitoring position of a vehicle hood; and

controlling the engine output correlative to the operator input to the accelerator pedal when the monitored position of the vehicle hood is open and the operator input to the transmission gear selector is one of a PARK and a NEUTRAL position.

2. The control method of claim 1, wherein controlling engine output comprises controlling engine speed correlative to the operator input to the accelerator pedal.

3. The control method of claim 2, wherein controlling engine speed comprises controlling engine speed to an idle speed when the operator input to the accelerator pedal is substantially 0%, and controlling engine speed to a maximum engine speed when the operator input to the accelerator pedal is substantially 100%.

4. The control method of claim 1, wherein controlling the engine output comprises inducing a change in engine speed correlative to a change in the operator input to the accelerator pedal.

5. The control method of claim 2, wherein controlling engine speed comprises controlling flow rate of engine intake air.

6. The control method of claim 5, wherein controlling flow rate of engine intake air comprises controlling open position of an engine throttle device based upon the operator input to the accelerator pedal.

7. The control method of claim 1, further comprising controlling torque output from the electric machine when the monitored position of the vehicle hood is open and the transmission gear selector is in one of the PARK and the NEUTRAL positions.

8. The control method of claim 7, further comprising controlling electric loading from the electric machine based upon an operator input to a brake pedal.

9. The control method of claim 7, wherein controlling torque output from the electric machine comprises controlling torque output from the electric machine to zero torque.

10. The control method of claim 7, further comprising constraining changes in state-of-charge of an electric energy storage device operative to transmit power to the electric machine.

11. The control method of claim 1, wherein the hybrid powertrain system operates in an input-split operating state.

12. The control method of claim 1, wherein the hybrid powertrain system comprises a compound-split hybrid configuration.

13. Control method for a hybrid powertrain system including an engine and an electric machine selectively operatively coupled to a transmission device to transmit torque therebetween and an electric energy storage device configured to transmit power to the electric machine, the method comprising:

monitoring an accelerator pedal position and a transmission gear selector position;

monitoring an input from a hood switch; and

constraining a change in a state-of-charge of the electric energy storage device and to control engine speed correlative to the accelerator pedal position when the input from the hood switch indicates the hood is open and the transmission gear selector is one of a PARK position and a NEUTRAL position.

14. The control method of claim 13, wherein constraining the change in a state-of-charge of the electric energy storage device comprises limiting change in available power from the electric energy storage device.

15. The control method of claim 14, wherein controlling engine speed comprises controlling intake air flow to the engine to induce a change in engine speed correlative to a change in the operator input to the accelerator pedal.

16. Control system for a vehicular powertrain system including an engine and an electromechanical transmission and an electric machine arranged in an input-split hybrid configuration and selectively operatively controllable to transmit torque therebetween and to a driveline, the control system comprising:

a control module signally connected to a plurality of input devices and configured to execute program code stored on a computer readable medium to control the powertrain, the program code comprising;

code to monitor operator inputs;

code to determine an intent to service the vehicle based upon the operator inputs;

code to command the electric machine to generate a net torque output of zero; and

,

code to control the engine speed correlative to an operator depression of an accelerator pedal.

17. The control system of claim 16, wherein the operator inputs comprise a hood switch and a transmission gear selector, wherein intent to service is determined by the hood switch indicating a open vehicle hood and the transmission gear selector indicating one of a PARK position and a NEUTRAL position.

18. The control system of claim 17, wherein the operator inputs further comprise an accelerator pedal, further comprising code to control the engine speed ranging substantially linearly from an idle speed correlated to the accelerator pedal indicating 0% depression to a maximum engine speed correlated to the accelerator pedal indicating 100% depression.

19. The control system of claim 18, wherein the code to control the engine speed comprises code to control intake air flow based upon the accelerator pedal position.

20. The control system of claim 19, wherein the operator inputs further comprise a brake pedal, further comprising code to decouple the electric machine from the driveline and to control the electric machine to induce a torque load on the engine based upon brake pedal depression.