Method for operating an internal combustion engine for a hybrid powertrain system

• US 8,219,303 B2
• Filed: 10/18/2008
• Issued: 07/10/2012
• Est. Priority Date: 11/05/2007
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG, Daimler AG (Mercedes-Benz Group AG), Chrysler Group LLC (Stellantis NV)
• Original Assignee: Bayerische Motoren Werke AG, GM Global Technology Operations LLC (General Motors Company), Daimler AG (Mercedes-Benz Group AG), Chrysler Group LLC (Stellantis NV)
• Inventors: Schwenke, R. Travis, Brandel, Todd D.
• Primary Examiner(s): Cheung, Mary
• Assistant Examiner(s): Tsui, Kyle K
• Application Number:
  US12/253,952
• Publication Number:
  US 20090118914A1
• Time in Patent Office: 1,361 Days
• Field of Search: 701/52, 701/53, 701/54, 701/104, 701/105, 701/112, 701/113, 701/111, 903/904, 903/905
• US Class Current: 701/111
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• 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 2240/486 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2510/0685 Engine crank angle
• CPC Class Codes: B60W 2510/083 Torque
• CPC Class Codes: B60W 2510/1025 Input torque
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 2710/1022 Input torque
• CPC Class Codes: B60W 2710/105 Output torque
• CPC Class Codes: B60W 50/0097 : Predicting future conditions
• CPC Class Codes: B60W 50/04 : Monitoring the functioning of the control system
• CPC Class Codes: F02D 35/024 : using an estimation
• CPC Class Codes: F02N 11/08 : Circuits or control means specially adapted for starting of engines
• CPC Class Codes: F16H 2037/0866 : Power split variators with distributing differentials, with the output of the CVT connected or connectable to the output shaft
• CPC Class Codes: F16H 2037/102 : the input or output shaft of the transmission is connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/104 : Power split variators with one end of the CVT connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/106 : with switching means to provide two variator modes or ranges
• CPC Class Codes: F16H 3/728 : with means to change ratio in the mechanical gearing
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility

Abstract

A hybrid powertrain system includes an internal combustion engine operatively connected to a second torque machine to transmit torque to an output member. A method for operating the hybrid powertrain system includes monitoring an operator torque request, determining an output torque command based upon the operator torque request, commanding a transition between an engine-off state and an engine-on state, monitoring an engine crank angle, spinning the engine unfueled, estimating cylinder pressure based upon the engine crank angle during the spinning of the engine, predicting a cylinder pulse torque based upon the cylinder pressure, determining a cancellation torque for the second torque machine based upon the predicted cylinder pulse torque, and controlling motor torque output from the second torque machine based upon the cancellation torque and the output torque command.

Claims

1. A method for operating a hybrid powertrain system including an internal combustion engine operatively connected to first and second torque machines to transmit torque to an output member, the method comprising:

monitoring an operator torque request;

determining an output torque command based upon the operator torque request;

commanding a transition between an engine-off state and an engine-on state;

monitoring an engine crank angle;

operating the first torque machine to spin the engine unfueled;

estimating cylinder pressure based upon the engine crank angle during the spinning of the engine;

predicting a cylinder pulse torque based upon the cylinder pressure;

determining a cancellation torque for the first torque machine based upon the predicted cylinder pulse torque; and

controlling the motor torque output of the first torque machine in response to both the cancellation torque and the output torque command and controlling the motor torque output of the second torque machine only in response to the output torque command.

2. The method of claim 1, further comprising predicting the cylinder pulse torque based upon the estimated cylinder pressure and a torque ratio.

3. The method of claim 1, wherein determining the cancellation torque for the first torque machine based upon the predicted cylinder pulse torque comprises determining the cancellation torque for the first torque machine during the spinning of the engine unfueled.

4. The method of claim 1, further comprising:

fueling the engine and decreasing the cancellation torque during spinning of the engine subsequent to the fueling of the engine.

5. The method of claim 1, wherein controlling the motor torque output of the first torque machine based upon the cancellation torque and the output torque command and controlling the motor torque output of the second torque machine only in response to the output torque command occurs during the spinning of the engine unfueled and during spinning of the engine fueled prior to firing the engine.

6. The method of claim 1, wherein commanding the transition between the engine-off state and the engine-on state comprises commanding the transition from the engine-off state to the engine-on state.

7. The method of claim 1, wherein commanding the transition between the engine-off state and the engine-on state comprises commanding the transition from the engine-on state to the engine-off state.

8. The method of claim 1, further comprising the hybrid powertrain system including the internal combustion engine operatively connected to the first and second torque machines to transmit torque to the output member via a transmission;

and

wherein controlling the motor torque output of the first torque machine in response to both the cancellation torque and the output torque command and controlling the motor torque output of the second torque machine only in response to the output torque command comprises operating the transmission in a neutral mode and controlling the motor torque output of the first torque machine in response to both the cancellation torque and the output torque command and controlling the motor torque output of the second torque machine only in response to the output torque command.