Method for operating an internal combustion engine to transmit power to a driveline

• US 8,121,766 B2
• Filed: 09/29/2008
• Issued: 02/21/2012
• Est. Priority Date: 11/04/2007
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG, Daimler AG (Mercedes-Benz Group AG), FCA US 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: Heap, Anthony H., Wu, Bin, Brunssen, Wilfried, McConnell, Jason J, Kim, Kee Yong, Medema, Brian R
• Primary Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US12/239,862
• Publication Number:
  US 20090118999A1
• Time in Patent Office: 1,240 Days
• Field of Search: 701/51, 701/53, 701/54, 701/79, 701/84, 701/87, 701/101, 477/3, 477/7
• US Class Current: 701/54
• 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: B60L 2240/486 Operating parameters
• CPC Class Codes: B60W 10/04 including control of propulsion units
• 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 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/1015 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2510/1025 Input 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 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 30/1882 characterised by the working point of the engine, e.g. by using engine output chart
• 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
• CPC Class Codes: Y02T 10/84 : Data processing systems or methods, management, administration

Abstract

A method for operating an engine includes defining a two-dimensional search region based upon an input power transmittable between the internal combustion engine and an electromechanical transmission. The method further includes iteratively dividing the two-dimensional search region into a plurality of subregions based upon one of the input power and the input speed, iteratively determining an engine operating point within each of the subregions, iteratively calculating an operating cost to operate the internal combustion engine and the electromechanical transmission to meet the operator torque request for each engine operating point within each of the subregions, and iteratively identifying the subregion having a minimum operating cost to meet the operator torque request. A preferred engine operating point is determined based upon the engine operating point within the identified subregion having the minimum operating cost to meet the operator torque request.

Claims

1. A method for operating an internal combustion engine mechanically coupled to an electro-mechanical transmission to transmit power to a driveline in response to an operator torque request, the method comprising:

defining a two-dimensional search region based upon an input power transmittable

between the internal combustion engine and the electro-mechanical transmission;

iteratively

dividing the two-dimensional search region into a plurality of subregions based upon one of the input power and an input speed transmittable from the internal combustion engine to the electro-mechanical transmission,

determining an engine operating point within each of the subregions,

calculating an operating cost to operate the internal combustion engine and the electro-mechanical transmission to meet the operator torque request for each engine operating point within each of the subregions,

identifying the subregion having a minimum operating cost to meet the operator torque request; and

determining a preferred engine operating point based upon the engine operating point within the identified subregion having the minimum operating cost to meet the operator torque request.

2. The method of claim 1, further comprising defining a two-dimensional search area based upon input power transmittable between the internal combustion engine and the electro-mechanical transmission.

3. The method of claim 2, wherein the two-dimensional search area comprises a range of permissible input speeds and a range of permissible input torques.

4. The method of claim 2, wherein the two-dimensional search area comprises a range of permissible input powers and a range of permissible input speeds.

5. The method of claim 1, comprising dividing the two-dimensional search region into a plurality of rectangular-shaped subregions.

6. The method of claim 1, comprising determining an engine operating point located at a geometric center of each of the subregions.

7. The method of claim 1, further comprising controlling the input speed and the input torque of the internal combustion engine based on the preferred engine operating point.

8. The method of claim 1, comprising calculating the operating cost based upon vehicle driveability, fuel economy, emissions, and battery usage.

9. The method of claim 1, wherein each engine operating point in each subregion comprises a precalibrated normalized engine operating point.

10. The method of claim 1, wherein the method comprises one of ten iterations and eleven iterations.

11. A method for operating an internal combustion engine mechanically connected to an electro-mechanical transmission to transmit power to a driveline in response to an operator torque request, the method comprising:

defining a two-dimensional search region comprising an input torque range and an input speed range transmittable from the internal combustion engine to the electro-mechanical transmission;

iteratively

dividing the two-dimensional search region into a plurality of subregions based upon one of the input torque and an input speed transmittable from the internal combustion engine to the electro-mechanical transmission,

determining an engine operating point within each of subregions,

calculating an operating cost to operate the internal combustion engine and the electro-mechanical transmission to meet the operator torque request for each of the engine operating points within each of the subregions,

identifying the subregion having a minimum operating cost based on the operator torque request; and

determining a preferred input speed and a preferred input torque for operating the internal combustion engine based upon the iteratively identified subregion having the minimum operating cost based on the operator torque request.

12. The method of claim 11, further comprising:

identifying a two-dimensional search area comprising a range of permissible input torques and a range of permissible input speeds transmittable from the internal combustion engine to the electro-mechanical transmission;

dividing the two-dimensional search area into the plurality of search regions based upon the input torque and the input speed;

determining an engine operating point within each of the plurality of search regions;

calculating an operating cost in response to the operator torque request for each of the engine operating points within each of the plurality of search regions; and

selecting the search region having a minimum calculated operating cost in response to the operator torque request for the engine operating points within the plurality of search regions.

13. The method of claim 11, comprising dividing the two-dimensional search region into a plurality of rectangular-shaped subregions.

14. The method of claim 11, comprising determining an engine operating point located at a geometric center of each subregion.

15. The method of claim 11, further comprising controlling the input speed and the input torque of the internal combustion engine based on the preferred engine operating point.

16. The method of claim 11, comprising calculating the operating costs based upon vehicle driveability, fuel economy, emissions, and battery usage.

17. The method of claim 11, wherein each engine operating point in each subregion comprises a precalibrated normalized engine operating point.

18. The method of claim 11 comprising dividing the two-dimensional search region into a plurality of subregions by iteratively alternating dividing search regions based upon input torques and input speeds.

19. The method of claim 11, comprising dividing the two-dimensional search region into three subregions.

20. The method of claim 11, wherein the method comprises one of ten iterations and eleven iterations.