CONTROL ARCHITECTURE AND METHOD TO EVALUATE ENGINE OFF OPERATION OF A HYBRID POWERTRAIN SYSTEM OPERATING IN A CONTINUOUSLY VARIABLE MODE

• US 20080287255A1
• Filed: 05/14/2007
• Published: 11/20/2008
• Est. Priority Date: 05/14/2007
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Snyder, Bryan R.
• Granted Patent: US 7,991,519 B2
• Time in Patent Office: Days
• US Class Current: 477/110
• 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 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• 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 10/10 including control of change-speed gearings
• 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 20/30 Control strategies involving selection of transmission gear ratio control of change speed gearings, together with other vehicle sub-units B60W10/10; HEV transmission gearing B60K6/36; gearings and control thereof F16H
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/081 Speed
• CPC Class Codes: B60W 2510/083 Torque
• CPC Class Codes: B60W 2510/1025 : Input torque
• CPC Class Codes: B60W 2540/10 : Accelerator pedal position
• CPC Class Codes: B60W 2540/16 : Ratio selector position
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/105 : Output torque
• CPC Class Codes: B60W 30/18027 : Drive off, accelerating from standstill
• 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 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/84 : Data processing systems or methods, management, administration

Abstract

There is provided a method and apparatus to determine operating conditions for a powertrain comprising an internal combustion engine and first and second electrical machines and an electro-mechanical transmission selectively operative to transmit torque therebetween. The method comprises determining a torque output and an operating cost for operating the first and second electrical machines of the hybrid transmission effective to meet an operator torque request when the engine is operating in an engine-off operating state. Determining the torque output for operating the first and second electrical machines comprises executing a predetermined system equation effective to determine motor torque outputs from each of the first and second electrical machines based upon the selected parametric value for the input torque and the operator torque request.

Claims

1. Method to determine operating conditions for a powertrain comprising an internal combustion engine and first and second electrical machines and an electro-mechanical transmission selectively operative to transmit torque therebetween, the method comprising determining an operating cost for operating the first and second electrical machines of the hybrid transmission to meet an operator torque request when the engine is operating in an engine-off operating state.

2. The method of claim 1, further comprising determining torque outputs from the first and second electrical machines of the hybrid transmission to meet the operator torque request.

3. The method of claim 1, further comprising determining the torque outputs from each of the first and second electrical machines for operating the hybrid transmission in a first continuously variable mode.

4. The method of claim 3, further comprising determining the torque outputs from each of the first and second electrical machines for operating the hybrid transmission in a second continuously variable mode.

5. The method of claim 1, wherein determining torque output for operating the first and second electrical machines comprises executing a predetermined system equation to determine motor torque outputs from each of the first and second electrical machines based upon the selected parametric value for the input torque and the operator torque request.

6. The method of claim 1, wherein the engine-off operating state comprises the engine crankshaft speed being zero revolutions per minute.

7. The method of claim 6, further comprising the engine being decoupled from the hybrid transmission.

8. Apparatus, comprising:

a distributed control module architecture comprising;

a plurality of control modules adapted to control operation of a hybrid powertrain;

the hybrid powertrain comprising an internal combustion engine and first and second electrical machines and an electro-mechanical transmission selectively operative to transmit torque therebetween;

the transmission selectively operative in one of first and second continuously variable operating modes through selective actuation of a plurality of torque-transfer clutches; and

,

the control modules adapted to execute machine code stored therein, the code comprising;

code to determine motor torque outputs and an operating cost for operating the first and second electrical machines of the hybrid transmission to meet an operator torque request when the engine is operating in an engine-off operating state.

9. The apparatus of claim 8, wherein the code further comprises an executable system equation to determine the motor torque outputs from each of the first and second electrical machines based upon the selected parametric value for the input torque and the operator torque request.

10. The apparatus of claim 9, wherein the code further comprises code to determine the motor torque outputs from each of the first and second electrical machines when the hybrid transmission operates in the first continuously variable mode.

11. The apparatus of claim 8, wherein the transmission further comprises a two-mode, compound split transmission selectively operative in one of the continuously variable operating modes through selective actuation of one of the torque-transfer clutches.

12. The apparatus of claim 11, further comprising the transmission operative in the first continuously variable operating mode through selective actuation of a first torque-transfer clutch.

13. The apparatus of claim 11, further comprising the transmission operative in the second continuously variable operating mode through selective actuation of a second torque-transfer clutch.

14. The apparatus of claim 8, wherein the code further comprises code to determine the motor torque outputs from each of the first and second electrical machines when the hybrid transmission operates in the second continuously variable mode.

15. The apparatus of claim 8, wherein code to determine the operating cost for operating the first and second electrical machines of the hybrid transmission effective to meet an operator torque request when the engine is operating in an engine-off operating state comprises code to determine operating system losses exclusive of fuel-consumption costs.

16. The apparatus of claim 15, wherein the operating costs are determined based upon an electrical battery power cost associated with the motor torques for the first and second electrical machines comprising electrical system losses, heat losses, electrical machine power losses and internal battery power losses.

17. 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, the method comprising:

monitoring an operator torque request, and, available battery power;

identifying at least one permissible powertrain operating range state comprising an engine-off state;

determining torque outputs from the first and second electrical machines to achieve a powertrain torque output to meet the operator torque request in the engine-off state;

determining an operating cost for operating the first and second electrical machines to achieve the powertrain torque output to meet the operator torque request in the engine-off state; and

,

selectively controlling the powertrain in one of the engine-off operating range states to meet the operator torque request based upon the operating cost.

18. The method of claim 17, wherein the permissible powertrain operating range states comprising the engine-off state further comprises one of a first and a second continuously variable operating mode.

19. The method of claim 17, wherein selectively controlling the powertrain in one of the engine-off operating range states further comprises:

selectively actuating one of a plurality of torque-transfer clutches and deactivating the engine to achieve the engine-off state to transmit torque from the electric machines to substantially meet the operator torque request.

20. The method of claim 19, wherein the engine-off state comprises the engine crankshaft speed being zero revolutions per minute.