System and method for managing the period of a control loop for controlling an engine using model predictive control

• US 9,435,274 B2
• Filed: 03/26/2014
• Issued: 09/06/2016
• Est. Priority Date: 03/26/2014
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Wong, Kevin C., Whitney, Christopher E., Bemporad, Alberto, Bernardini, Daniele
• Primary Examiner(s): SOLIS, ERICK R
• Application Number:
  US14/225,492
• Publication Number:
  US 20150275783A1
• Time in Patent Office: 895 Days
• US Class Current: 1/1
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 13/0219 by shifting the phase, i.e. the opening periods of the valves are constant
• CPC Class Codes: F02D 2041/001 for engines with variable valve actuation
• CPC Class Codes: F02D 2041/1412 using a predictive controller
• CPC Class Codes: F02D 2041/1418 Several control loops, either as alternatives or simultaneous
• CPC Class Codes: F02D 2041/1433 using a model or simulation of the system
• CPC Class Codes: F02D 28/00 Programme-control of engines
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/1401 characterised by the control or regulation method F02D41/1473, F02D41/1477 take precedence
• CPC Class Codes: F02D 41/26 using computer, e.g. microprocessor
• CPC Class Codes: F02D 41/263 the program execution being modifiable by physical parameters
• CPC Class Codes: G05B 13/048 using a predictor
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A system according to the present disclosure includes a model predictive control (MPC) module, an actuator module, and a remedial action module. The MPC module performs MPC tasks that include predicting operating parameters for a set of possible target values and determining a cost for the set of possible target values based on the predicted operating parameters. The MPC tasks also include selecting the set of possible target values from multiple sets of possible target values based on the cost and setting target values to the possible target values of the selected set. The actuator module controls an actuator of an engine based on at least one of the target values. The remedial action module selectively takes a remedial action based on at least one of an amount of time that elapses as the MPC tasks are performed and a number of iterations of the MPC tasks that are performed.

Claims

1. A system comprising:

a model predictive control (MPC) module that performs MPC tasks including;

determining predicted operating parameters for a set of possible target values;

determining a cost for the set of possible target values based on the predicted operating parameters;

selecting the set of possible target values from multiple sets of possible target values based on the cost; and

setting target values to the possible target values of the selected set;

an actuator module that controls an actuator of an engine based on at least one of the target values; and

a remedial action module that selectively takes a remedial action based on at least one of an amount of time that elapses as the MPC tasks are performed and a number of iterations of the MPC tasks that are performed.

2. The system of claim 1 wherein the remedial action module instructs the MPC module to suspend the MPC tasks when the elapsed time is greater than a first period.

3. The system of claim 2 wherein:

the remedial action module instructs the MPC module to resume the MPC tasks when other tasks are complete; and

the other tasks have less priority than the MPC tasks.

4. The system of claim 2 wherein:

the remedial action module instructs the MPC module to set the target values for a present control loop independent of the possible target values for iterations started during the present control loop when the elapsed time is greater than a second period; and

the second period is greater than the first period.

5. The system of claim 4 wherein the remedial action module instructs the MPC module to set the target values for the present control loop to the target values set during a previous control loop when the elapsed time is greater than the second period.

6. The system of claim 4 wherein:

the MPC module sets the target values for the present control loop and a future control loop when completing the iterations started during the present control loop; and

when the elapsed time is greater than the second period, the remedial action module instructs the MPC module to set the target values for the present control loop to the target values set for the future control loop during a previous control loop.

7. The system of claim 4 wherein the remedial action module instructs the MPC module to refrain from restarting the MPC tasks during a future control loop when the elapsed time is greater than the second period.

8. The system of claim 4 wherein:

the remedial action module takes the remedial action when the elapsed time is greater than a third period; and

the third period is greater than the second period.

9. The system of claim 8 wherein the remedial action includes at least one of limiting the torque output of the engine and activating a service indicator.

10. The system of claim 8 wherein the MPC module determines the cost for each of the sets of possible target values based on differences between the possible target values and reference values, the system further comprising a backup module that sets the target values for the present control loop to reference values when the elapsed time is greater than the third period.

11. A method comprising:

performing MPC tasks including;

determining predicted operating parameters for a set of possible target values;

determining a cost for the set of possible target values based on the predicted operating parameters;

selecting the set of possible target values from multiple sets of possible target values based on the cost; and

setting target values to the possible target values of the selected set;

controlling an actuator of an engine based on at least one of the target values; and

selectively taking a remedial action based on at least one of an amount of time that elapses as the MPC tasks are performed and a number of iterations of the MPC tasks that are performed.

12. The method of claim 11 further comprising suspending the MPC tasks when the elapsed time is greater than a first period.

13. The method of claim 12 further comprising resuming the MPC tasks when other tasks are complete, wherein the other tasks have less priority than the MPC tasks.

14. The method of claim 12 further comprising setting the target values for a present control loop independent of the possible target values for iterations started during the present control loop when the elapsed time is greater than a second period, wherein the second period is greater than the first period.

15. The method of claim 14 further comprising setting the target values for the present control loop to the target values set during a previous control loop when the elapsed time is greater than the second period.

16. The method of claim 14 further comprising:

setting the target values for the present control loop and a future control loop when completing the iterations started during the present control loop; and

when the elapsed time is greater than the second period, setting the target values for the present control loop to the target values set for the future control loop during a previous control loop.

17. The method of claim 14 further comprising refraining from restarting the MPC tasks during a future control loop when the elapsed time is greater than the second period.

18. The method of claim 14 further comprising taking the remedial action when the elapsed time is greater than a third period, wherein the third period is greater than the second period.

19. The method of claim 18 wherein the remedial action includes at least one of limiting the torque output of the engine and activating a service indicator.

20. The method of claim 18 further comprising:

determining the cost for each of the sets of possible target values based on differences between the possible target values and reference values; and

setting the target values for the present control loop to reference values when the elapsed time is greater than the third period.