Method for electric power boosting in a powertrain system

• US 8,067,908 B2
• Filed: 10/22/2008
• Issued: 11/29/2011
• Est. Priority Date: 11/04/2007
• 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 LLC (Stellantis NV)
• Inventors: Thompson, Scott J, Heap, Anthony H., Tamai, Goro
• Primary Examiner(s): Masih; Karen
• Application Number:
  US12/255,815
• Publication Number:
  US 20090115354A1
• Time in Patent Office: 1,133 Days
• Field of Search: 318/139, 318/812, 318/727, 318/432, 318/376, 318/8, 701/99, 180/65.285
• US Class Current: 318/139
• 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 2240/443 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 10/26 for electrical energy, e.g. batteries or capacitors
• 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 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2050/0009 Proportional differential [PD] controller
• CPC Class Codes: B60W 2050/0031 Mathematical model of the vehicle
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/104 Output speed
• CPC Class Codes: B60W 2510/24 Energy storage means
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2710/086 Power
• CPC Class Codes: B60W 2710/105 : Output torque
• CPC Class Codes: B60W 50/04 : Monitoring the functioning of the control system
• 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 10/40 : Engine management systems
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles

Abstract

A powertrain system is operative to transfer power between an input member and a plurality of power actuators and an output member to generate an output torque. The power actuators are connected to an energy storage device. A method for controlling the powertrain system includes monitoring operating conditions of the powertrain system, determining an electric power limit for output power of the energy storage device, selectively enabling electric power boost based upon the operating conditions of the powertrain system, and increasing the electric power limit when electric power boost is enabled.

Claims

1. Method for controlling a powertrain system operative to transfer power between an input member and a plurality of power actuators and an output member to generate an output torque, the power actuators connected to an energy storage device, the method comprising:

monitoring operating conditions of the powertrain system;

determining an electric power limit for output power of the energy storage device;

selectively enabling electric power boost based upon the operating conditions of the powertrain system; and

increasing the electric power limit when electric power boost is enabled.

2. The method of claim 1, further comprising:

selectively disabling electric power boost based upon the operating conditions of the powertrain system; and

decreasing the electric power limit when electric power boost is disabled.

3. The method of claim 1, further comprising:

determining an output torque of the output member based upon the electric power limit.

4. The method of claim 1, further comprising:

determining a set of output torque constraints based upon the electric power limit, and

determining an output torque of the output member based upon the output torque constraints.

5. The method of claim 1, further comprising:

monitoring operating conditions of the powertrain system including at least one of a state of charge of the energy storage device, an engine torque, an engine capacity limit, an engine state, an engine starting cycle operation, and an engine stopping cycle operation; and

enabling electric power boost based upon at least one of the state of charge of the energy storage device, the engine state, the engine torque, the engine starting cycle, and the engine stopping cycle.

6. The method of claim 1, further comprising:

determining whether a state of charge of the energy storage device is greater than a threshold state of charge; and

enabling electric power boost when the state of charge of the energy storage device is greater than the threshold state of charge.

7. The method of claim 1, further comprising:

determining an engine state as a cylinder deactivation state; and

enabling electric power boost when the engine state is the cylinder deactivation state.

8. The method of claim 1, further comprising:

determining whether an engine torque is greater than a threshold torque; and

enabling electric power boost when the engine torque is greater than the threshold torque.

9. The method of claim 1, further comprising:

enabling electric power boost; and

increasing the electric power limit when the electric power boost is enabled.

10. The method of claim 9, wherein the electric power limit is ramped up over time at a calibrated ramp up rate when electric power boost is enabled.

11. The method of claim 1, further comprising:

disabling electric power boost; and

decreasing the electric power limit when the electric power boost is disabled.

12. The method of claim 11, wherein the electric power limit is ramped down over time at a calibrated ramp down rate based upon the output speed of the output member.

13. Method for managing electric power in a powertrain system comprising an energy storage device, an engine, a second torque generating device and a transmission device operative to transfer power among an output member, the engine and the second torque generating device, the second torque generating device electrically coupled to an energy storage device, the method comprising:

monitoring operating conditions of the powertrain system;

providing a maximum electric power limit and a minimum electric power limit;

selectively enabling and disabling electric power boost based on the operating conditions of the powertrain system; and

modifying the electric power limit by one of boosting the electric power limit when electric power boost is enabled and pinching the electric power limit when the electric power boost is disabled.

14. The method of claim 13, further comprising:

determining a set of output torque constraints based upon the electric power limit; and

determining an output torque of the output member based upon the output torque constraints.

15. The method of claim 13, further comprising:

monitoring operating conditions of the powertrain system including at least one of a state of charge of the energy storage device, an engine torque, an engine capacity limit, an engine state, an engine starting cycle operation, and an engine stopping cycle operation; and

enabling electric power boost based upon at least one of the state of charge of the energy storage device, the engine state, the engine torque, the engine starting cycle, and the engine stopping cycle.

16. The method of claim 13, further comprising:

determining whether a state of charge of the energy storage device is greater than a threshold state of charge; and

enabling electric power boost when the state of charge of the energy storage device is greater than the threshold state of charge.

17. The method of claim 13, further comprising:

determining an engine state as a cylinder deactivation state; and

enabling electric power boost when the engine state is the cylinder deactivation state.

18. The method of claim 13, further comprising:

determining whether an input torque from an engine is greater than a threshold input torque; and

enabling electric power boost when the input torque from the engine is greater than the threshold input torque.

19. The method of claim 13, further comprising:

enabling electric power boost; and

increasing the electric power limit when the electric power boost is enabled, wherein the electric power limit is ramped up over time at a calibrated ramp up rate when electric power boost is enabled.

20. Method for managing electric power in a powertrain system comprising an energy storage device, an engine, a second torque generating device and a transmission device operative to transfer power among an output member, the engine and the second torque generating device, the second torque generating device electrically coupled to an energy storage device, the method comprising:

providing a maximum electric power limit and a minimum electric power limit;

monitoring operating conditions of the powertrain system including at least one of a state of charge of the energy storage device, an engine torque, an engine capacity limit, an engine state, an engine starting cycle operation, and an engine stopping cycle operation;

enabling electric power boost based upon at least one of the state of charge of the energy storage device, the engine state, the engine torque, the engine starting cycle, and the engine stopping cycle; and

increasing the electric power limit when electric power boost is enabled.