Method for controlling electric boost in a hybrid powertrain

• US 8,099,204 B2
• Filed: 10/22/2008
• Issued: 01/17/2012
• 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, Daimler AG (Mercedes-Benz Group AG), GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust), Chrysler LLC (Stellantis NV)
• Inventors: Snyder, Bryan R., Heap, Anthony H., McConnell, Jason J, Tamai, Goro
• Primary Examiner(s): Trammell, James
• Assistant Examiner(s): Shafi, Muhammad
• Application Number:
  US12/255,957
• Publication Number:
  US 20090118964A1
• Time in Patent Office: 1,182 Days
• Field of Search: 701/22, 701/81, 701/51, 318/158, 180174-179, 180/202, 180/6.28, 180/6.5, 180/214, 180/216, 180/218, 180/242, 180/279, 180/53.5, 180/60, 180 651- 658, 180/407, 180/412, 180/415, 180/422, 180/443, 180/65.21, 280/735, 280/707, 280/422, 340/428, 903902-960
• US Class Current: 701/22
• 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: 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 10/115 with planetary gears
• CPC Class Codes: B60W 10/24 including control of energy storage means
• 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 20/19 for achieving enhanced acceleration
• CPC Class Codes: B60W 2050/0006 Digital architecture hierarchy
• CPC Class Codes: B60W 2050/0022 Gains, weighting coefficients or weighting functions
• CPC Class Codes: B60W 2510/0671 Engine manifold pressure
• CPC Class Codes: B60W 2510/0676 Engine temperature
• 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 2555/20 : Ambient conditions, e.g. wind or rain
• CPC Class Codes: B60W 2710/083 : Torque
• 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 2200/201 : with three sets of orbital gears
• CPC Class Codes: F16H 2200/2041 : with four engaging means
• 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 powertrain system includes an engine coupled to an input member of a transmission operative to transmit power between the input member, a torque machine and an output member. The torque machine is connected to an energy storage device. The engine is selectively operative in engine states comprising an engine-on state and an engine-off state. A method for controlling a powertrain system includes determining a first power range for output power of the energy storage device, commanding the engine to transition from a first engine state to a second engine state, and expanding the first power range of the energy storage device and controlling the torque machine based upon the expanded power range of the energy storage device during the transition from the first engine state to the second engine state.

Claims

1. A method for controlling a powertrain system comprising an engine coupled to an input member of a transmission operative to transmit power between the input member, a torque machine and an output member, the torque machine connected to an energy storage device, the engine selectively operative in engine states comprising an engine-on state and an engine-off state during ongoing powertrain operation, wherein a control module performs the following steps comprising:

determining long-term electric power limits for output power of the energy storage device;

commanding the engine to transition from a first engine state to a second engine state during ongoing powertrain operation; and

adjusting the long-term electric power limits of the energy storage device and controlling the torque machine in response to the adjusted long-term electric power limits of the energy storage device during the transition from the first engine state to the second engine state;

the steps including;

monitoring output power of the energy storage device;

monitoring the engine for an autostart operating state;

determining a long-term electric power limit comprising a maximum electric power limit for output power of the energy storage device;

enabling an electric power boost when the engine is in the autostart operating engine operating state; and

adjusting the maximum electric power limit greater than the long-term electric power limit when the electric power boost is enabled;

and including,

monitoring the engine for an autostop operating state;

determining a long-term electric power limit comprising a minimum electric power limit for output power of the energy storage device;

enabling an electric power boost when the engine is in the autostop operating state; and

adjusting the minimum electric power limit to be less than the long-term electric power limit when the electric power boost is enabled.

2. The method of claim 1, wherein adjusting the long-term electric power limits of the energy storage device comprises adjusting the long-term electric power limits of the energy storage device until the adjusted long-term electric power limits meet a set of boost electric power limits.

3. The method of claim 1, wherein adjusting the long-term electric power limits of the energy storage device comprises adjusting the long-term electric power limits of the energy storage device at a calibrated rate.

4. The method of claim 1, further comprising:

controlling the torque machine in response to the adjusted long-term electric power limits of the energy storage device subsequent to the transition from the first engine state to the second engine state.

5. The method of claim 4, further comprising subsequently decreasing the adjusted long-term electric power limits of the energy storage device until the adjusted long-term electric power limits meet the long-term electric power limits.

6. The method of claim 5, wherein the long-term electric power limits are based upon long-term battery durability.

7. The method of claim 1, wherein controlling the torque machine in response to the adjusted long-term electric power limits of the energy storage device during the transition from the first engine state to the second engine state comprises controlling output torque of the output member within a set of output torque constraints in response to the adjusted long-term electric power limits of the energy storage device.

8. The method of claim 1, comprising adjusting the maximum electric power limit greater than the long-term electric power limit at a calibrated rate until the adjusted electric power limit meets a maximum boost electric power limit when the electric power boost is enabled.

9. The method of claim 1, further comprising:

disabling the electric power boost when the engine is not in the autostart operating engine operating state; and

decreasing the adjusted maximum electric power limit to the long-term electric power limit when the electric power boost is disabled.

10. The method of claim 9, comprising decreasing the adjusted maximum electric power limit to the long-term electric power limit at a calibrated rate when the electric power boost is disabled.

11. The method of claim 10, wherein the long-term electric power limits are based upon long-term battery durability.

12. The method of claim 1, comprising adjusting the minimum electric power limit to be less than the long-term electric power limit at a calibrated rate until the adjusted minimum electric power limit meets a minimum boost electric power limit when the electric power boost is enabled.

13. The method of claim 1, further comprising:

disabling the electric power boost when the engine is not in the autostop operating state; and

increasing the adjusted minimum electric power limit to the long-term electric power limit when the electric power boost is disabled.

14. The method of claim 13, comprising increasing the adjusted minimum electric power limit to the long-term electric power limit at a calibrated rate when the electric power boost is disabled.