Rate-based model predictive control method for internal combustion engine air path control

• US 9,581,080 B2
• Filed: 12/21/2012
• Issued: 02/28/2017
• Est. Priority Date: 12/21/2012
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation), Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation), Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Kolmanovsky, Ilya V, Huang, Mike
• Primary Examiner(s): Vo, Hieu T
• Assistant Examiner(s): MANLEY, SHERMAN D
• Application Number:
  US13/724,957
• Publication Number:
  US 20140174413A1
• Time in Patent Office: 1,530 Days
• US Class Current: 1/1
• CPC Class Codes: F02B 47/08 the substances including exhaust gas
• CPC Class Codes: F02D 2041/1412 using a predictive controller
• CPC Class Codes: F02D 2041/1416 Observer
• CPC Class Codes: F02D 2041/1434 Inverse model
• CPC Class Codes: F02D 41/0007 for control of turbo-charged or super-charged engines control of the pumps per se F02B37/12
• CPC Class Codes: F02D 41/005 according to engine operating conditions
• CPC Class Codes: F02D 41/0077 Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position EGR valve position sensor F02M26/48
• CPC Class Codes: F02D 41/1401 characterised by the control or regulation method F02D41/1473, F02D41/1477 take precedence
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A rate based model predictive controller for air path control for a diesel engine regulates turbine lift and EGR valve flow rate to specified set points by coordinated control of intake manifold air pressure and EGR valve flow rate. The controller utilizes a rate-based reduced order linear model for model predictive control.

Claims

1. A method for controlling an internal combustion engine having a controller controlling a variable geometry turbine and an EGR valve during engine operation, the method comprising:

developing a non-linear model using engine operating parameters;

developing a linear quadratic model predictive controller, based on the non-linear model, for each engine operating zone;

generating a rate based predictive model based on the linear quadratic model, and using the rate based predictive model in the controller responsive to engine intake manifold pressure and EGR valve flow rate, to generate requested engine turbine lift and requested EGR flow rate; and

controlling operation of the internal combustion engine based on the generated engine turbine lift and the generated EGR flow rate.

2. The method of claim 1 further comprising:

defining at least one engine operating zone about a center linearization point for engine speed ranges and fuel rate ranges.

3. The method of claim 2 further comprising:

linearizing the non-linear model at a center linearization point within an engine operating zone.

4. The method of claim 3 further comprising:

developing a second order reduced linear model based on the non-linear model.

5. The method of claim 4 further comprising:

generating the rate-based predictive model as a derivative of the linear model.

6. The method of claim 5 further comprising:

generating the linear model as a linear quadratic model in the form of a piecewise affine control law wherein;

u_k+1=u_k+T_s(F_ix_aug+G_i),ifH_ix_aug≦

K_k.

9. The method of claim 1 further comprising:

reducing the number of regions in each of the at least one engine operating zone by using a single time instant to enforce overshoot restraint of at least one controller output.

10. The method of claim 9 wherein:

the single time instant includes 20 time steps.

11. The method of claim 6 comprising:

estimating an engine state;

determining the region of the piecewise affine control law based on the estimated engine state;

applying feedback gain associated with the selected region of the piecewise affine control law to determine a control rate; and

integrating the control rate to determine a control value to be applied to one engine input.

7. A method for controlling an internal combustion engine having a controller controlling a variable geometry turbine and an EGR valve during engine operation, the method comprising:

using a rate-based predictive model in the controller responsive to engine intake manifold pressure and EGR valve flow rate, to generate requested engine turbine lift and requested EGR flow rate;

applying partial inversion to the rate-based predictive model controller to convert an EGR valve flow rate signal to an EGR valve position duty cycle signal and to convert a turbine lift signal to a turbine lift duty cycle signal; and

controlling operation of the internal combustion engine based on the converted EGR valve position duty cycle signal and the converted turbine lift duty cycle signal.

8. A method for controlling an internal combustion engine having a controller controlling a variable geometry turbine and an EGR valve during engine operation, the method comprising:

developing an EGR throttle controller according to;

12. A method for controlling an internal combustion engine having a controller, the method comprising:

controlling a variable geometry turbine and an EGR valve during engine operation by using a computer program tangibly embodied on a computer usable medium and comprising instructions that when executed by a processor is configured to;

use a rate-based predictive model, responsive to intake manifold pressure and requested EGR valve flow rate, to generate engine turbine lift and EGR flow rate; and

define at least one engine operating zone about a center linearization point for engine speed ranges and fuel rate ranges; and

control operation of the internal combustion engine based on the generated engine turbine lift and the generated EGR flow rate.

13. The method of claim 12, further comprising instructions for:

developing a non-linear model using operating parameters.

14. The method of claim 12, further comprising instructions for:

linearizing the non-linear model at a center linearization point within an engine operating zone.

15. The method of claim 14, further comprising instructions for:

generating the rate-based predictive model as a derivative of the non-linear model.

16. The method of claim 12, further comprising instructions for:

estimating an engine state;

determining the region of the piecewise affine control law based on the estimated engine state;

applying feedback gain associated with the selected region of the piecewise affine control law to determine a control rate; and

integrating the control rate to determine a control value to be applied to one engine input.