Method for operating an engine in a hybrid powertrain system

• US 8,010,247 B2
• Filed: 10/16/2008
• Issued: 08/30/2011
• Est. Priority Date: 11/03/2007
• Status: Active Grant

• Current Assignee: 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: Corsetti, Anthony James, Heap, Anthony H., Lahti, John L.
• Primary Examiner(s): Black; Thomas G
• Assistant Examiner(s): Coleman; Marthe Marc
• Application Number:
  US12/253,221
• Publication Number:
  US 20090118883A1
• Time in Patent Office: 1,048 Days
• Field of Search: 701/51, 701/22, 701/99, 701/103, 180/65.265, 180/65.1, 180/65.3, 180/65.4, 180/65.275, 290/45
• 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: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/443 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2050/0006 Digital architecture hierarchy
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/0671 Engine manifold pressure
• CPC Class Codes: B60W 2510/0676 Engine temperature
• CPC Class Codes: B60W 2510/085 Power
• CPC Class Codes: B60W 2510/1025 Input torque
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2510/246 Temperature
• 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 2710/0644 : Engine speed
• CPC Class Codes: B60W 2710/0666 : Engine torque
• CPC Class Codes: B60W 2710/0677 : Engine power
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/1011 : Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2710/1022 : Input torque
• CPC Class Codes: B60W 2710/1061 : Output power
• CPC Class Codes: B60W 30/1882 : characterised by the working point of the engine, e.g. by using engine output chart
• 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 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 10/40 : Engine management systems
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/84 : Data processing systems or methods, management, administration
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles

Abstract

An engine and an electric machine are operative to communicate tractive power with a transmission device to control output power to an output member. The electric machine is electrically coupled to an energy storage device. A method for controlling the engine and electric machine includes monitoring an operator request for power, monitoring a state of charge of the energy storage device, determining an operating cost for each of a plurality of candidate engine operating points based on the operator request for power and the state of charge of the energy storage device; and operating the engine at the candidate engine operating point having a preferred operating cost.

Claims

1. Method for controlling an engine and an electric machine operative to communicate tractive power with a transmission device to control output power to an output member, said electric machine electrically coupled to an energy storage device, the method comprising:

monitoring an operator request for power;

monitoring a state of charge of the energy storage device;

determining an operating cost for each of a plurality of candidate engine operating points for each of a plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device;

selecting a preferred engine state and a corresponding preferred engine operating point based on the operating costs of the candidate engine operating points for the candidate engine states; and

operating the engine at the preferred engine state and the corresponding preferred engine operating point.

2. The method of claim 1, wherein determining the operating cost for each of the plurality of candidate engine operating points for each of the plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device comprises determining an engine power loss cost for each of the plurality of candidate engine operating points.

3. The method of claim 2, wherein determining the operating cost for each of the plurality of candidate engine operating points for each of the plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device further comprises determining an engine power loss cost biasing factor based upon the state of charge of the energy storage device.

4. The method of claim 3, wherein determining the operating cost for each of the plurality of candidate engine operating points for each of the plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device further comprises determining a battery power loss cost.

5. The method of claim 4, wherein determining the operating cost for each of the plurality of candidate engine operating points for each of the plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device further comprises determining a battery power cost biasing factor based upon the state of charge of the energy storage device.

6. The method of claim 1, wherein determining the operating cost for each of the plurality of candidate engine operating points for each of the plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device comprises determining a mechanical power loss cost, an electric machine power loss cost, and a braking power loss cost.

7. The method of claim 1, wherein selecting the preferred engine state and the corresponding preferred engine operating point based on the operating costs of the candidate engine operating points for the candidate engine states further comprises:

determining a search range of engine operating points for each of the candidate engine states;

executing a search function within the search range to select candidate engine operating points within the search range for each of the candidate engine states based on operating costs;

and

selecting the preferred engine state and the corresponding preferred engine operating point as the candidate engine operating point for the candidate engine states having the lowest operating cost.

8. The method of claim 7, wherein determining a search range of engine operating points for each of the candidate engine states comprises determining search ranges of engine operating points for engine states comprising a fueled engine state and a fuel cutoff engine state.

9. The method of claim 1, wherein monitoring the operator power request comprises monitoring an operator torque request.

10. The method of claim 1, further comprising:

determining a preferred electric machine torque based on the preferred engine state and the corresponding preferred engine operating point, and

operating the electric machine based on the preferred electric machine torque.

11. The method of claim 1, wherein the engine operating point comprises an engine input torque to the transmission device.

12. Method for controlling an engine and an electric machine to communicate tractive power with a transmission device to control power to an output member, said electric machine electrically coupled to an energy storage device, the method comprising:

monitoring an operator request for power;

monitoring a state of charge of the energy storage device;

selecting a candidate engine operating point for each of a plurality of candidate engine states;

determining an operating cost for each of the candidate engine operating points for each of the plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device; and

operating the engine at the candidate engine operating point and the candidate engine state corresponding to a preferred operating cost.

13. The method of claim 12, wherein the candidate engine states comprise a fueled engine state and a fuel cutoff engine state.

14. The method of claim 12, wherein selecting the candidate engine operating point for the fueled engine state comprises determining a preferred engine operating point within a search range of candidate engine operating points.

15. The method of claim 12, wherein the candidate engine states comprise a fueled, all-cylinder state;

a fuel cutoff, all-cylinder state;

a fueled, cylinder deactivation state; and

a fuel cutoff cylinder deactivation state.

16. The method of claim 12, wherein the engine operating point comprises one of an engine speed, an engine torque and an engine power.

17. Method for controlling an engine and an electric machine to communicate tractive power with a transmission device to control output power to an output member, said electric machine electrically coupled to an energy storage device, the method comprising:

monitoring an operator torque request;

monitoring a state of charge of the energy storage device;

determining operating costs for a plurality of candidate engine torques for a plurality of candidate engine states based on the operator request for power and the state of charge of the energy storage device; and

operating the engine at a selected one of the candidate engine states and a selected one of the candidate engine torques having a minimum operating cost.