Method and apparatus for controlling a multi-mode transmission

• US 8,762,012 B2
• Filed: 05/01/2012
• Issued: 06/24/2014
• Est. Priority Date: 05/01/2012
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Hansen, R. Anthony, Pieper, Jeffrey Michael
• Primary Examiner(s): Algahaim, Helal A
• Assistant Examiner(s): PATEL, SHARDUL D
• Application Number:
  US13/460,906
• Publication Number:
  US 20130297156A1
• Time in Patent Office: 784 Days
• Field of Search: 701/51, 701/60, 475/5, 475/10, 475/271, 475/275, 475/276, 477/3, 477/5, 477/175
• US Class Current: 701/51
• CPC Class Codes: B60W 10/105 of electric type
• CPC Class Codes: B60W 20/20 Control strategies involving selection of hybrid configuration, e.g. selection between series or parallel configuration
• CPC Class Codes: B60W 2510/1015 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2510/1045 Output speed change rate
• CPC Class Codes: B60W 2520/28 Wheel speed
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 2710/1011 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60Y 2400/3032 Wheel speed sensors
• CPC Class Codes: F16H 2061/1284 the failing part is a sensor
• CPC Class Codes: F16H 59/44 dependent on machine speed of the machine, e.g. the vehicle
• CPC Class Codes: F16H 61/12 Detecting malfunction or potential malfunction, e.g. fail safe in control of hydrostatic gearing F16H61/4192; Circumventing or fixing failures

Abstract

A powertrain system includes a multi-mode transmission configured to transfer torque among an input member, torque machines and an output member. A method for controlling operation of the multi-mode transmission includes determining torque commands for the torque machines in response to a desired input speed of the input member and an output speed of the output member determined based upon an estimated wheel speed of a wheel of a driveline coupled to the output member. The estimated wheel speed of the wheel is set equal to a monitored wheel speed of the wheel upon detecting an abrupt decrease in the wheel speed. Torque commands are determined for the torque machines in response to the desired input speed and the monitored wheel speed.

Claims

1. Method for controlling operation of a multi-mode transmission configured to transfer torque among an input member coupled to an internal combustion engine, torque machines and an output member in one of a plurality of fixed gear modes, continuously variable modes and Neutral, the method comprising:

employing a closed-loop control scheme to determine torque commands for the torque machines in response to a desired input speed of the input member and an estimated wheel speed of a wheel of a driveline coupled to the output member; and

upon detecting an abrupt change in an output speed of the output member causing lockup of the output member, employing the closed-loop control scheme to determine torque commands for the torque machines in response to the desired input speed of the input member and a monitored wheel speed of the wheel of the driveline.

2. Method for controlling operation of a multi-mode transmission configured to transfer torque among an input member coupled to an internal combustion engine, torque machines and an output member, the method comprising:

determining torque commands for the torque machines in response to a desired input speed of the input member and an output speed of the output member, the output speed determined based upon an estimated wheel speed of a wheel of a driveline coupled to the output member; and

upon detecting an abrupt change in wheel speed of said wheel causing lockup of the output member, setting the estimated wheel speed equal to a monitored wheel speed and determining torque commands for the torque machines in response to said desired input speed and the monitored wheel speed.

3. The method of claim 2, wherein determining torque commands for the torque machines comprises employing a closed-loop control system to determine the torque commands based on the monitored wheel speed.

4. The method of claim 3, wherein employing the closed-loop control system to determine the torque commands comprises:

executing a closed-loop speed control system to determine torque errors based on the desired input speed and the monitored wheel speed; and

employing the torque errors to adjust the torque commands.

5. The method of claim 4, wherein the closed-loop speed control system to determine torque errors comprises a powertrain system estimator and a feedback controller.

6. The method of claim 4, wherein executing the closed-loop speed control system to determine torque errors comprises executing the closed-loop speed control system while the multi-mode transmission is in a fixed gear mode.

7. The method of claim 4, wherein executing the closed-loop speed control system to determine torque errors comprises executing the closed-loop speed control system while the multi-mode transmission is in a continuously variable mode.

8. The method of claim 4, wherein executing the closed-loop speed control system to determine torque errors comprises executing the closed-loop speed control system while the multi-mode transmission is in Neutral.

9. The method of claim 2, wherein the abrupt change in wheel speed comprises engagement of a transmission range selector in a Park position while the wheel is rotating.

10. The method of claim 2, wherein the abrupt change in wheel speed comprises a traction control maneuver.

11. The method of claim 2, wherein the abrupt change in the wheel speed comprises activation of an anti-lock brake system.

12. The method of claim 2, wherein the abrupt change in the wheel speed comprises acceleration on a low-friction road surface.

13. Method for controlling operation of a multi-mode transmission configured to transfer torque among an input member coupled to an internal combustion engine, torque machines and an output member in one of a plurality of fixed gear modes, continuously variable modes and Neutral, the method comprising:

employing a closed-loop control scheme to determine torque commands for the torque machines in response to a desired input speed of the input member and an estimated wheel speed of a wheel of a driveline coupled to the output member; and

in response to an outside force affecting a monitored parameter causing lockup of the output member, setting the estimated wheel speed equal to a monitored wheel speed and employing the closed-loop control scheme to determine torque commands for the torque machines in response to the desired input speed and the monitored wheel speed.

14. The method of claim 13, wherein employing the closed-loop control system to determine the torque commands comprises:

executing a closed-loop speed control system to determine torque errors in response to the desired input speed and the monitored wheel speed; and

employing the torque errors to adjust the torque commands.

15. The method of claim 14, wherein the closed-loop speed control system to determine torque errors comprises a powertrain system estimator and a feedback controller.

16. The method of claim 14, wherein executing the closed-loop speed control system to determine torque errors comprises executing the closed-loop speed control system while the multi-mode transmission is in a fixed gear mode.

17. The method of claim 14, wherein executing the closed-loop speed control system to determine torque errors comprises executing the closed-loop speed control system while the multi-mode transmission is in a continuously variable mode.

18. The method of claim 14, wherein executing the closed-loop speed control system to determine torque errors comprises executing the closed-loop speed control system while the multi-mode transmission is in Neutral.