METHOD FOR DETERMINING INPUT SPEED ACCELERATION LIMITS IN A HYBRID TRANSMISSION

• US 20090118094A1
• Filed: 10/21/2008
• Published: 05/07/2009
• Est. Priority Date: 11/03/2007
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG, Daimler AG (Mercedes-Benz Group AG), Chrysler Group LLC (Stellantis NV)
• Original Assignee: BMW AG (Bayerische Motoren Werke AG), GM Global Technology Operations Incorporated (General Motors Company), Daimler AG (Mercedes-Benz Group AG), Chrysler LLC (Stellantis NV)
• Inventors: Heap, Anthony H., Hsieh, Tung-Ming
• Granted Patent: US 8,002,667 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: 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 10/02 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 10/26 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2050/0022 Gains, weighting coefficients or weighting functions
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/0661 Torque change rate
• CPC Class Codes: B60W 2510/1005 Transmission ratio engaged
• 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 2710/026 : Slip change rate
• CPC Class Codes: B60W 2710/027 : Clutch torque
• CPC Class Codes: B60W 2710/086 : Power
• CPC Class Codes: B60W 2710/1022 : Input torque
• CPC Class Codes: B60W 2710/105 : Output torque
• 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 10/62 : Hybrid vehicles

Abstract

A powertrain system includes a transmission operative to transfer power between an input member and first and second torque machines and an output member. The first and second torque machines are connected to an energy storage device and the transmission is operative in a continuously variable operating range state. A method for controlling the powertrain system includes selecting an independently controllable parameter for the powertrain system, determining maximum and minimum motor torque constraints for the first and second torque machines and determining maximum and minimum power constraints for the energy storage device, determining maximum and minimum states for the independently controllable parameter for the powertrain system, and determining an achievable operating range for a parameter of interest based upon the maximum and minimum states for the independently controllable parameter for the powertrain system, the maximum and minimum motor torque constraints for the first and second torque machines and the maximum and minimum power constraints for the energy storage device.

Claims

1. A method for controlling a powertrain system including a transmission operative to transfer power between an input member and first and second torque machines and an output member, the first and second torque machines connected to an energy storage device and the transmission operative in a continuously variable operating range state, the method comprising:

selecting an independently controllable parameter for the powertrain system;

determining maximum and minimum motor torque constraints for the first and second torque machines and determining maximum and minimum power constraints for the energy storage device;

determining maximum and minimum states for the independently controllable parameter for the powertrain system; and

determining an achievable operating range for a parameter of interest based upon the maximum and minimum states for the independently controllable parameter for the powertrain system, the maximum and minimum motor torque constraints for the first and second torque machines and the maximum and minimum power constraints for the energy storage device.

2. The method of claim 1, comprising:

selecting the independently controllable parameter comprising an output torque to the output member; and

determining an achievable operating range of an input acceleration rate for the input member based upon maximum and minimum states for the output torque to the output member and the maximum and minimum motor torque constraints for the first and second torque machines, and the maximum and minimum power constraints for the energy storage device.

3. The method of claim 2, further comprising:

selecting independently controllable parameters comprising the output torque to the output member and a clutch reactive torque of an applied torque transfer clutch; and

determining an achievable operating range of an input acceleration rate for the input member based upon maximum and minimum states for the output torque to the output member and the clutch reactive torque of the applied torque transfer clutch, the maximum and minimum motor torque constraints for the first and second torque machines, and the maximum and minimum power constraints for the energy storage device.

4. The method of claim 1, further comprising:

operating the transmission in a neutral state;

selecting an independently controllable parameter comprising a clutch slip acceleration of a torque transfer clutch; and

determining an achievable operating range of input acceleration rate for the input member based upon maximum and minimum states for the clutch slip acceleration of the torque transfer clutch, the maximum and minimum motor torque constraints for the first and second torque machines, and the maximum and minimum power constraints for the energy storage device.

5. The method of claim 1, comprising:

operating the transmission in a neutral state;

selecting an independently controllable parameter comprising an input acceleration rate for the input member; and

determining an achievable operating range of clutch slip accelerations of a torque transfer clutch based upon maximum and minimum states for the input acceleration rate for the input member, the maximum and minimum motor torque constraints for the first and second torque machines, and the maximum and minimum power constraints for the energy storage device.

6. The method of claim 1, further comprising:

operating the transmission in a neutral state;

selecting an independently controllable parameter comprising an acceleration rate of a first element; and

determining an achievable operating range comprising an achievable operating range for an acceleration rate of a second element based upon maximum and minimum states for the acceleration rate for the first element, the maximum and minimum motor torque constraints for the first and second torque machines, and the maximum and minimum power constraints for the energy storage device.

7. The method of claim 1, further comprising:

deriving equations for the independently controllable parameters based upon power outputs for the first and second torque machines;

deriving equations for the parameter of interest;

deriving equations for the maximum and minimum motor torque constraints for the first and second torque machines and the maximum and minimum power constraints for the energy storage device; and

determining the achievable operating range for the parameter of interest by simultaneously solving the equations for the independently controllable parameters, the equations for the parameter of interest, and the equations for the maximum and minimum motor torque constraints for the first and second torque machines and the maximum and minimum power constraints for the energy storage device.

8. The method of claim 7, further comprising transforming the equations for the independently controllable parameters, the equations for the parameter of interest, and the equations for the maximum and minimum motor torque constraints for the first and second torque machines and the maximum and minimum power constraints for the energy storage device to a second coordinate system.

9. The method of claim 8, further comprising simultaneously solving the transformed equations for the independently controllable parameters, the parameter of interest, the maximum and minimum motor torque constraints for the first and second torque machines, and the maximum and minimum power constraints for the energy storage device in the second coordinate system to determine a preferred solution comprising an achievable operating range for the parameter of interest in the second coordinate system.

10. The method of claim 9, further comprising retransforming the preferred solution comprising the achievable operating range for the parameter of interest in the second coordinate system to determine the achievable operating range for the parameter of interest.

11. A method for controlling a powertrain system including an engine operatively connected to an input member of a transmission operative to transfer power between the input member and torque machines and an output member through selective application of torque transfer clutches, the torque machines connected to an energy storage device and the transmission operative in a continuously variable operating range state and a neutral state, the method comprising:

selecting independently controllable parameters for the powertrain system;

determining maximum and minimum motor torque constraints for the torque machines and determining maximum and minimum power constraints for the energy storage device;

deriving equations for the independently controlled parameters based upon power outputs from the torque machines;

deriving an equation for an independent parameter of interest based upon the power outputs from the torque machines;

determining maximum and minimum states for the independently controllable parameters for the powertrain system;

simultaneously solving the equations for the independently controlled parameters and the equation for the independent parameter of interest; and

determining an achievable operating range for the parameter of interest based upon the simultaneously solved equations and the maximum and minimum states for the independently controllable parameters for the powertrain system, the maximum and minimum motor torque constraints for the torque machines and the maximum and minimum power constraints for the energy storage device.

12. The method of claim 11, further comprising:

operating the transmission in the continuously variable operating range state;

selecting independently controllable parameters comprising an output torque to the output member and a clutch reactive torque of an applied torque transfer clutch; and

determining an achievable operating range for an input acceleration rate for the input member.

13. The method of claim 11, further comprising:

operating the transmission in the neutral state;

selecting an independently controllable parameter comprising a clutch slip acceleration of a torque transfer clutch; and

determining an achievable operating range for input acceleration rate for the input member.

14. The method of claim 11, comprising

operating the transmission in the neutral state;

selecting an independently controllable parameter comprising an input acceleration rate for the input member; and

determining an achievable operating range for clutch slip acceleration of a torque transfer clutch.

15. A method for controlling a powertrain system including an engine operatively connected to an input member of a transmission operative to transfer power between the input member and torque machines and an output member through selective application of torque transfer clutches, the torque machines connected to an energy storage device and the transmission operative in a continuously variable operating range state and a neutral state, the method comprising:

selecting independently controllable parameters for the powertrain system;

determining maximum and minimum motor torque constraints for the torque machines and determining maximum and minimum power constraints for the energy storage device;

deriving equations for the independently controlled parameters based upon torque outputs from the torque machines;

deriving an equation for an independent parameter of interest based upon the torque outputs from the torque machines;

determining maximum and minimum states for the independently controllable parameters for the powertrain system;

simultaneously solving the equations for the independently controlled parameters and the equation for the independent parameter of interest; and

determining an achievable operating range for the parameter of interest based upon the simultaneously solved equations and the maximum and minimum states for the independently controllable parameters for the powertrain system, the maximum and minimum motor torque constraints for the torque machines and the maximum and minimum power constraints for the energy storage device.

16. The method of claim 15, further comprising transforming the equations for the independently controllable parameters, the equations for the parameter of interest, and the equations for the maximum and minimum motor torque constraints for the first and second torque machines and the maximum and minimum power constraints for the energy storage device to a second coordinate system.

17. The method of claim 16, further comprising simultaneously solving the transformed equations for the independently controllable parameters, the parameter of interest, the maximum and minimum motor torque constraints for the first and second torque machines, and the maximum and minimum power constraints for the energy storage device in the second coordinate system to determine a preferred solution comprising an achievable operating range for the parameter of interest in the second coordinate system.

18. The method of claim 17, further comprising retransforming the preferred solution comprising the achievable operating range for the parameter of interest in the second coordinate system to determine the achievable operating range for the parameter of interest.