METHOD AND CONTROL ARCHITECTURE FOR SELECTION OF OPTIMAL ENGINE INPUT TORQUE FOR A POWERTRAIN SYSTEM

• US 20090069989A1
• Filed: 09/11/2007
• Published: 03/12/2009
• Est. Priority Date: 09/11/2007
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Heap, Anthony H.
• Granted Patent: US 7,983,823 B2
• Time in Patent Office: Days
• US Class Current: 701/51
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• 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 30/1882 characterised by the working point of the engine, e.g. by using engine output chart
• 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 and article of manufacture are provided for operating an internal combustion engine adapted to transmit torque to a hybrid transmission. The method comprises determining engine input torque transmittable to the hybrid transmission for each of a plurality of engine states. Costs are determined for operating the engine and hybrid transmission in the engine states to substantially meet an operator torque request. A preferred engine state is selected based upon the determined costs. The engine is controlled based upon the preferred engine state to substantially meet an operator torque request.

Claims

1. Method for operating an internal combustion engine adapted to transmit torque to a hybrid transmission, comprising:

determining engine input torque transmittable to the hybrid transmission for each of a plurality of engine states;

determining costs for operating the engine and hybrid transmission in the engine states to substantially meet an operator torque request;

selecting a preferred engine state based upon the determined costs; and

,

controlling the engine based upon the preferred engine state to substantially meet an operator torque request.

2. The method of claim 1, wherein the engine states comprise a normal engine operating state, a cylinder deactivation state, an engine fuel-cutoff state, and, an engine fuel-cutoff state with cylinder deactivation.

3. The method of claim 2, wherein determining costs comprises determining a minimum powertrain system operating cost and an associated engine input torque to substantially meet the operator torque request at the minimum powertrain system operating cost when the engine state comprises one of the normal engine state and the cylinder deactivation state.

4. The method of claim 3, wherein determining costs comprises evaluating operation of the powertrain system to determine an operating cost to substantially meet the operator torque request when the engine state comprises one of the engine fuel cut-off state and the engine fuel cut-off state with cylinder deactivation.

5. The method of claim 1, further comprising determining engine input torque transmittable to the hybrid transmission for each of the engine states based upon a current operating range of the hybrid transmission.

6. The method of claim 5, wherein the current operating range of the hybrid transmission comprises one of a plurality of fixed gear modes and two continuously variable modes.

7. The method of claim 1, further comprising controlling the engine to an allowable engine state.

8. The method of claim 1, wherein controlling the engine based upon the preferred engine state to substantially meet an operator torque request comprises controlling engine input torque to the hybrid transmission.

9. The method of claim 8, further comprising controlling the engine input torque and a desired engine state.

10. The method of claim 1, wherein the engine input torque transmittable to the hybrid transmission for each of the engine states is determinable based upon the operator torque request, engine operating conditions, and engine operating constraints.

11. Method for operating a powertrain comprising an internal combustion engine and first and second electrical machines and an electro-mechanical transmission selectively operative to transmit torque therebetween and to transmit torque to a driveline, the method comprising:

determining allowable engine states and an operator torque request;

determining engine input torque transmittable to the hybrid powertrain system at each of the allowable engine states;

determining powertrain system costs for operating the engine and hybrid transmission in the allowable engine states to substantially meet the operator torque request;

selecting a preferred engine state based upon the determined powertrain system costs for the allowable engine states; and

,

controlling the engine based upon the preferred engine state to substantially meet the operator torque request.

12. The method of claim 11, further comprising commanding operation of the engine to the preferred engine state.

13. The method of claim 11, wherein the engine input torque for each engine state is determined based upon an engine input speed to the transmission, a transmission output speed, a current operating range state of the transmission, the operator torque request, and available power from an electrical storage device operatively connected to the first and second electrical machines.

14. Article of manufacture, comprising a storage medium having a computer program encoded therein for effecting a method to operate an internal combustion engine adapted to transmit torque to a hybrid transmission, the program comprising:

code to determine a current operating range state of the hybrid transmission;

code to determine engine input torque transmittable to the hybrid transmission for each of a plurality of engine states;

code to determine costs for operating the engine and hybrid transmission in the engine states to substantially meet an operator torque request;

code to select a preferred engine state based upon the determined costs; and

,

code to control the engine based upon the preferred engine state to substantially meet an operator torque request.

15. The article of manufacture of claim 14, wherein the hybrid transmission comprises an electro-mechanical transmission selectively operatively connected to first and second electrical machines each selectively operative to transmit torque therebetween.

16. The article of manufacture of claim 14, wherein the preferred engine state comprises one of normal engine operating state, a cylinder deactivation state, an engine fuel cut-off state, and, an engine fuel cut-off state with cylinder deactivation.

17. Control system for a hybrid powertrain, comprising:

a distributed control module architecture comprising a plurality of signally connected control modules operative to control an internal combustion engine and first and second electrical machines and an electro-mechanical transmission selectively operative to transmit torque therebetween;

the control system adapted to execute a plurality of algorithms contained therein the algorithm comprising;

code to determine a current operating range state of the transmission;

code to determine engine input torque transmittable to the hybrid transmission for each of a plurality of engine states;

code to determine costs for operating the engine and hybrid transmission in the engine states to substantially meet an operator torque request;

code to select a preferred engine state based upon the preferred costs for the engine states; and

,

code to control the engine based upon the preferred engine state to substantially meet an operator torque request.

18. The control system of claim 17, wherein the code to select a preferred engine operating condition comprises code to select a preferred engine input torque transmitted to the transmission and a preferred engine state.

19. The control system of claim 18, wherein the preferred engine state comprises one of the engine fully operational, the engine operating with deactivated cylinders, and the engine in a fuel-cutoff mode.

20. The control system of claim 17, further comprising code to control the engine based upon the preferred engine input torque and the preferred engine state.

21. The control system of claim 17, further comprising the transmission selectively operative in one of a plurality of operating range states through selective actuation of a plurality of torque-transfer clutches, the operating range states comprising a plurality of fixed gear operating range states and two continuously variable operating range states.