Method and apparatus for fault detection in a torque machine of a powertrain system

• US 8,731,765 B2
• Filed: 06/28/2011
• Issued: 05/20/2014
• Est. Priority Date: 06/28/2011
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Wang, Wei D., Bae, Bon Ho, Zepeda, Reynaldo Arturo Suazo, Godavarthy, Satish
• Primary Examiner(s): Jabr, Fadey
• Assistant Examiner(s): HEINLE, COURTNEY D
• Application Number:
  US13/170,428
• Publication Number:
  US 20130006453A1
• Time in Patent Office: 1,057 Days
• Field of Search: 701/29.1, 701/22, 701/51, 701/99, 903/902, 318/3, 318/139, 318/445, 318490-494, 318/521, 318/558, 318/689, 318/690, 318/700, 318/725, 318/727, 180/65.1, 477/3, 477/7, 477/906, 702/57, 702/117, 702/123
• US Class Current: 701/29.2
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 3/0061 relating to electrical machines
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• 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 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: B60W 50/0205 Diagnosing or detecting failures; Failure detection models
• CPC Class Codes: B60W 50/029 Adapting to failures or work around with other constraints, e.g. circumvention by avoiding use of failed parts
• CPC Class Codes: B60W 50/038 Limiting the input power, torque or speed
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility

Abstract

A method for operating a powertrain system including a torque machine mechanically coupled to an internal combustion engine includes, upon detecting a pending fault associated with a power switch configured to control power flow to the torque machine, disabling torque output from the torque machine and executing retry events. The retry events are iteratively executed with a debounce time period preceding each retry event. Presence of a fault associated with the power switch is detected when a quantity of the retry events during a time window exceeds a threshold.

Claims

1. Method for operating a powertrain system including a torque machine mechanically coupled to an internal combustion engine, comprising:

upon detecting a pending hardware desaturation fault associated with one of a plurality of power switches configured to control power flow to the torque machine,

employing a diagnostic circuit to disable control signals to all of the power switches,

executing a motor control hardware reset to re-enable operation of all of the power switches, and

executing retry events comprising

re-enabling the control signals to all the power switches,

ramping torque capability for the torque machine from zero to its expected value and

re-enabling disabled powertrain system functions, wherein the retry event;

are iteratively executed with a debounce time period preceding each retry event; and

detecting, by the diagnostic circuit, a presence of a mature hardware desaturation fault associated with the power switch when a quantity of the retry events during a time window exceeds a threshold.

2. The method of claim 1, wherein each retry event further includes:

commanding power flow to the torque machine; and

monitoring the power switches configured to control the power flow to the torque machine.

3. The method of claim 2, wherein commanding power flow to the torque machine comprises controlling activation of the power switches.

4. The method of claim 2, wherein monitoring the power switches comprises monitoring power flow through each of the power switches.

5. The method of claim 1, further comprising disabling an autostop function associated with the internal combustion engine upon detecting the pending hardware desaturation fault associated with one of the power switches.

6. The method of claim 1, further comprising disabling a deceleration fuel cutoff function associated with the internal combustion engine upon detecting the pending hardware desaturation fault associated with one of the power switches.

7. The method of claim 1, further comprising immediately enabling an autostart function associated with the internal combustion engine upon detecting the pending hardware desaturation fault associated with one of the power switches.

8. The method of claim 1, wherein employing the diagnostic circuit to disable control signals to all of the power switches comprises setting a motor torque capability function to 0 Nm.

9. The method of claim 1, further comprising discontinuing executing the retry events when the pending fault clears.

10. The method of claim 1, wherein detecting a pending hardware desaturation fault associated with one of the plurality of power switches configured to control power flow to the torque machine comprises monitoring fault signals from the plurality of power switches.

11. Method for operating a powertrain system including a torque machine mechanically coupled to an internal combustion engine, comprising:

monitoring fault signals output from a plurality of power switches configured to control power flow to the torque machine;

employing a diagnostic circuit to disable torque output from the torque machine upon detecting a pending fault associated with one of the power switches;

executing a motor control hardware reset to re-enable operation of all of the power switches to execute retry events;

iteratively executing the retry events subsequent to disabling torque output comprising

re-enabling the control signals to all the power switches,

ramping torque capability for the torque machine from zero to its expected value and

re-enabling disabled powertrain system functions; and

detecting, by the diagnostic circuit, a mature fault when a quantity of the retry events during a time window exceeds a threshold.

12. The method of claim 11, wherein iteratively executing the retry events includes iteratively executing the retry events with a debounce time period preceding each retry event.

13. The method of claim 12, wherein iteratively executing the retry events comprises waiting the debounce time period before commanding power flow to the torque machine.

14. The method of claim 13, wherein commanding power flow to the torque machine comprises controlling activation of the power switches.

15. The method of claim 11, further comprising disabling an autostop function associated with the internal combustion engine upon detecting the pending fault associated with one of the power switches.

16. The method of claim 11, further comprising disabling a deceleration fuel cutoff function associated with the internal combustion engine upon detecting the pending fault associated with one of the power switches.

17. The method of claim 11, further comprising immediately enabling an autostart function associated with the internal combustion engine upon detecting the pending fault associated with one of the power switches.

18. The method of claim 11, further comprising discontinuing executing the retry events when the pending fault clears.

19. Method for operating a powertrain system including a torque machine mechanically coupled to an internal combustion engine, comprising:

disabling, by a diagnostic circuit, torque output from the torque machine, executing a motor control hardware reset to re-enable operation of all of the power switches to execute retry events, and executing retry events upon detecting a pending fault associated with a power switch configured to control power flow to the torque machine, said retry events comprising

re-enabling the control signals to all the power switches,

ramping torque capability for the torque machine from zero to its expected value and

re-enabling disabled powertrain system functions;

discontinuing executing the retry events when the pending fault clears; and

reporting presence of a mature fault associated with the power switch when a quantity of the retry events during a time window exceeds a threshold.