METHOD FOR MANAGING LASH IN A DRIVELINE

• US 20090118945A1
• Filed: 10/22/2008
• Published: 05/07/2009
• Est. Priority Date: 11/04/2007
• 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), Daimler AG (Mercedes-Benz Group AG), GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust), Chrysler LLC (Stellantis NV)
• Inventors: McGrath, Seamus T., Heap, Anthony H., Morris, Robert L., McConnell, Jason J.
• Granted Patent: US 8,818,660 B2
• Time in Patent Office: Days
• 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: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/443 Torque
• 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 10/115 with planetary gears
• 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 2510/0657 Engine torque
• CPC Class Codes: B60W 2510/0661 Torque change rate
• CPC Class Codes: B60W 2510/0666 Engine power
• CPC Class Codes: B60W 2510/083 Torque
• CPC Class Codes: B60W 2510/1005 Transmission ratio engaged
• CPC Class Codes: B60W 2510/104 Output speed
• CPC Class Codes: B60W 2510/105 Output torque
• CPC Class Codes: B60W 2520/28 Wheel speed
• CPC Class Codes: B60W 2540/10 : Accelerator pedal position
• CPC Class Codes: B60W 2540/12 : Brake pedal position
• CPC Class Codes: B60W 2552/15 : Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/1038 : Output speed
• CPC Class Codes: B60W 2710/105 : Output torque
• CPC Class Codes: B60W 2710/1055 : Output torque change rate
• CPC Class Codes: B60W 2720/28 : Wheel speed
• 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
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility

Abstract

A hybrid powertrain system includes a transmission device operative to transfer power between an input member, a torque machine and an output member, the output member coupled to a driveline coupled to a wheel to transfer tractive torque therebetween. A method for controlling the hybrid powertrain system includes monitoring an operator torque request, determining an operating range state of the transmission device, determining a net output torque to the output member based upon the operator torque request, determining a lash state of the driveline, and determining a command for transferring output torque to the output member based upon the operating range state of the transmission device, the net output torque, and the lash state of the driveline.

Claims

1. Method for controlling a hybrid powertrain system including a transmission device operative to transfer power between an input member, a torque machine and an output member, the output member coupled to a driveline coupled to a wheel to transfer tractive torque therebetween, the method comprising:

monitoring an operator torque request;

determining an operating range state of the transmission device;

determining a net output torque to the output member based upon the operator torque request;

determining a lash state of the driveline; and

determining a command for transferring output torque to the output member based upon the operating range state of the transmission device, the net output torque, and the lash state of the driveline.

2. The method of claim 1, wherein the lash state comprises one a positive lash state, a negative lash state, and a neutral lash state.

3. The method of claim 2, further comprising:

providing a threshold on a rate of change of the output torque; and

setting the command for transferring output torque to the output member equal to the net output torque when the lash state is in the neutral lash state and when the net output torque is less than the threshold on the rate of change of the output torque.

4. The method of claim 3, further comprising:

providing a first threshold on a negative rate of change of the output torque; and

constraining the command for transferring output torque to the output member to the first threshold on the negative rate of change of the output torque when the lash state is the negative lash state.

5. The method of claim 3, further comprising:

providing a second threshold on a positive rate of change of the output torque; and

constraining the command for transferring output torque to the output member to the second threshold on the positive rate of change of the output torque when the lash state is the positive lash state.

6. The method of claim 5, further comprising controlling motor torque to the torque machine based upon the command for transferring output torque to the output member.

7. The method of claim 1, further comprising determining a lash state of the driveline based upon a wheel speed and an output speed of the output member.

8. The method of claim 7, further comprising determining the lash state based upon the wheel speed, the output speed of the output member, and a torque of the driveline.

9. The method of claim 8, further comprising determining the lash state based upon a motor torque command for the torque machine, an input torque at the input member, a friction brake torque measurement, and a road load torque.

10. Method for managing lash in a driveline operably coupled to a hybrid powertrain system, the hybrid powertrain system including an engine coupled to an input member of a hybrid transmission, the hybrid transmission operative to transmit torque between the input member and first and second torque machines and an output member coupled to the driveline to transmit torque to a wheel, the method comprising:

monitoring an operator torque request;

determining an operating range state of the transmission device;

determining a net output torque of the output member based upon the operator torque request;

determining an output speed of the output member and a wheel speed of the wheel;

determining one of a positive lash state, a negative lash state, and a neutral lash state of the driveline based upon the output speed of the output member and the wheel speed of the wheel; and

commanding motor torques to the first and second torque machines based upon the operating range state of the transmission device, the net output torque and the lash state of the driveline.

11. The method of claim 10, further comprising:

providing a threshold on a rate of change of the output torque; and

setting the command for transferring output torque to the output member equal to the net output torque when the lash state is in the neutral lash state and when the net output torque is less than the threshold on the rate of change of the output torque.

12. The method of claim 11, further comprising:

providing a first threshold on a negative rate of change of the output torque; and

constraining the command for transferring output torque to the output member to the first threshold on the negative rate of change of the output torque when the lash state is the negative lash state.

13. The method of claim 12, further comprising:

providing a second threshold on a positive rate of change of the output torque; and

constraining the command for transferring output torque to the output member to the second threshold on the positive rate of change of the output torque when the lash state is the positive lash state.

14. The method of claim 13, further comprising controlling motor torques to the first and second torque machines based upon the command for transferring output torque to the output member.

15. The method of claim 10, further comprising determining a lash state of the driveline based upon a wheel speed and an output speed of the output member.

16. The method of claim 15, further comprising determining the lash state based upon the wheel speed, the output speed of the output member, and a torque of the driveline.

17. The method of claim 16, further comprising determining the lash state based upon a motor torque command for the torque machine, an input torque at the input member, a friction brake torque measurement, and a road load torque.

18. Method for managing lash in a driveline operably coupled to a hybrid powertrain system, the hybrid powertrain system including an engine, a second torque generating machine, a transmission device and an energy storage device connected to the second torque generating machine, the transmission device operative to transfer power between an output member, the engine and the second torque generating machine, the output member providing torque to the driveline providing torque to a wheel, the method comprising:

monitoring an operator torque request;

determining a net output torque of the output member based upon the operator torque request;

determining an operating range state of the transmission device comprising one of a plurality of fixed gear modes and a continuously variable mode;

determining an output speed of the output member and a wheel speed;

determining one of a positive lash state, a negative lash state, and a neutral lash state of the driveline based upon the output speed of the output member and the wheel speed of the wheel; and

determining a motor torque command to the second torque generating machine based upon the operating range state of the transmission device, the net output torque and the lash state of the driveline.