Method and engine control unit for controlling an internal combustion engine

• US 8,155,857 B2
• Filed: 04/08/2009
• Issued: 04/10/2012
• Est. Priority Date: 04/09/2008
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Loeffler, Axel, Ulmer, Holger
• Primary Examiner(s): WOLFE JR, WILLIS RAY
• Application Number:
  US12/384,874
• Publication Number:
  US 20090259385A1
• Time in Patent Office: 1,098 Days
• Field of Search: 123/406.19, 123/406.26, 123/435, 123/436, 123/478, 123/480, 123/674, 701101-105, 701/108, 701/109, 701/111, 701/114, 701/115, 7311402-11409, 731/141.6, 702/182, 702/183, 702/185
• US Class Current: 701/102
• CPC Class Codes: F02D 2041/1433 using a model or simulation of the system
• CPC Class Codes: F02D 2041/1434 Inverse model
• CPC Class Codes: F02D 35/023 by determining the cylinder pressure
• CPC Class Codes: F02D 35/028 by determining the combustion timing or phasing
• CPC Class Codes: F02D 41/1402 Adaptive control
• CPC Class Codes: F02D 41/1405 Neural network control

Abstract

A method for controlling an internal combustion engine includes: providing a setpoint value of at least one combustion attribute on the basis of a setpoint value characteristics map; determining from a control variable characteristics map a value of a characteristics-map-based control variable for controlling the engine; ascertaining with the aid of a data-based model a value of a modified control variable for controlling the engine, the data-based model specifying a predicted combustion attribute as a function of a real value of the combustion attribute of the preceding combustion, and the value of the modified control variable for controlling the engine being ascertained from the predicted combustion attribute; and providing a real control variable set to a value that is a function of the value of the characteristics-map-based control variable and/or the value of the modified control variable.

Claims

1. A computer-readable storage medium storing a computer program including a plurality of program codes which, when executed by a computer, performs a method for controlling an internal combustion engine, the method comprising:

providing an operating-point-dependent setpoint value of at least one combustion attribute of a combustion in the internal combustion engine on the basis of a setpoint value characteristics map, the combustion attribute corresponding to a variable characterizing the combustion in the internal combustion engine;

determining from a control variable characteristics map a value of a characteristics-map-based control variable for controlling the internal combustion engine;

ascertaining with the aid of a data-based model a value of a modified control variable for controlling the internal combustion engine, the data-based model ascertaining the value of the modified control variable as a function of a real value of the combustion attribute of the preceding combustion and the characteristics map-based control variable, the real value of the combustion attribute being ascertained by measuring the combustion attribute while the internal combustion engine is in operation, wherein the data-based model is configured to be adaptable as a function of the setpoint value of the combustion attribute and the real value of the combustion attribute; and

providing a real control variable to the internal combustion engine to control the internal combustion engine, the real control variable being set to a value that is a function of at least one of the value of the characteristics map-based control variable and the value of the modified control variable.

2. An engine control unit for controlling an internal combustion engine, comprising:

a memory unit storing a setpoint-value-characteristics map and a control-variable-characteristics map, wherein the setpoint-value-characteristics map is configured to provide, as a function of an operating point of the internal combustion engine, a setpoint value of a combustion attribute of a combustion in the internal combustion engine, the combustion attribute corresponding to a variable characterizing the combustion in the internal combustion engine, and wherein the control-variable-characteristics map is used to determine a value of a characteristics-map-based control variable for controlling the internal combustion engine;

a calculator unit configured to ascertain with the aid of a data-based model a value of a modified control variable for controlling the internal combustion engine, wherein the data-based model specifies a predicted combustion attribute as a function of the real value of the combustion attribute of the preceding combustion and the characteristics-map-based control variable, the real value of the combustion attribute being ascertained by measuring the combustion attribute while the internal combustion engine is in operation, wherein the value of the modified control variable for controlling the internal combustion engine is ascertained from the predicted combustion attribute by an assignment function, and wherein the data-based model is configured to be adaptable as a function of the setpoint value of the combustion attribute and the real value of the combustion attribute; and

a coordinator unit configured to provide a real control variable to the internal combustion engine to control the internal combustion engine, the real control variable being set to a value that is a function of at least one of the value of the characteristics map-based control variable and the value of the modified control variable.

3. The engine control unit as recited in claim 2, wherein the calculator unit is configured to provide, as an output variable of the data-based model, a reliability measure indicating a reliability for the value of the modified control variable, and wherein the coordinator unit is configured to provide, as a function of the reliability measure, one of the value of the modified control variable or the value of the characteristics-map-based control variable as the real control variable for controlling the internal combustion engine.

4. The engine control unit as recited in claim 2, further comprising:

an adaptation unit configured to minimize a deviation between the setpoint value of the combustion attribute and the real value of the combustion attribute by adapting the control-variable-characteristics map in a cylinder-specific manner.

5. A method for controlling an internal combustion engine, comprising:

providing an operating-point-dependent setpoint value of at least one combustion attribute of a combustion in the internal combustion engine on the basis of a setpoint value characteristics map, the combustion attribute corresponding to a variable characterizing the combustion in the internal combustion engine;

determining from a control variable characteristics map a value of a characteristics-map-based control variable for controlling the internal combustion engine;

ascertaining with the aid of a data-based model a value of a modified control variable for controlling the internal combustion engine, the data-based model ascertaining the value of the modified control variable as a function of a real value of the combustion attribute of the preceding combustion and the characteristics map-based control variable, the real value of the combustion attribute being ascertained by measuring the combustion attribute while the internal combustion engine is in operation, wherein the data-based model is configured to be adaptable as a function of the setpoint value of the combustion attribute and the real value of the combustion attribute; and

providing a real control variable to the internal combustion engine to control the internal combustion engine, the real control variable being set to a value that is a function of at least one of the value of the characteristics map-based control variable and the value of the modified control variable.

6. The method as recited in claim 5, wherein the data-based model provides a reliability measure as an output variable, the reliability measure indicating a reliability for the value of the modified control variable.

7. The method as recited in claim 6, wherein, as a function of the reliability measure, one of the value of the modified control variable or the value of the characteristics-map-based control variable is provided as the real control variable for controlling the internal combustion engine.

8. The method as recited in claim 6, wherein a value of the real control variable for controlling the internal combustion engine results as a function of the reliability measure, the value of the modified control variable and the value of the characteristics map-based control variable, the reliability measure being used as the weighting variable between the value of the modified control variable and the value of the characteristics map-based control variable.

9. The method as recited in claim 6, the data-based model being a function of the result of a threshold value comparison, wherein the result is adapted with the aid of the setpoint value of the combustion attribute and the real value of the combustion attribute.

10. The method as recited in claim 9, wherein a deviation between the setpoint value of the combustion attribute and the real value of the combustion attribute is minimized by adapting the control variable characteristics map in a cylinder-specific manner.

11. The method as recited in claim 9, wherein the data-based model specifies a predicted combustion attribute as a function of the real value of the combustion attribute of the preceding combustion and the characteristics-map-based control variable, the value of the modified control variable for controlling the internal combustion engine being ascertained from the predicted combustion attribute by an assignment function corresponding to an inverse function describing the dependence of a combustion attribute on a control variable.