METHOD FOR OPERATING AN INTERNAL COMBUSTION ENGINE

• US 20090320787A1
• Filed: 05/04/2007
• Published: 12/31/2009
• Est. Priority Date: 06/08/2006
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Wunderlin, Simon, Wagner, Horst, Kessler, Michael, Bossmeyer, Thomas, Damitz, Jens
• Granted Patent: US 8,141,540 B2
• Time in Patent Office: Days
• US Class Current: 123/295
• CPC Class Codes: F02D 2200/1012 Engine speed gradient
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/0057 Specific combustion modes combustion modes per se F02D41/3017
• CPC Class Codes: F02D 41/0085 Balancing of cylinder outputs, e.g. speed, torque or air-fuel ratio
• CPC Class Codes: F02D 41/1498 measuring engine roughness
• CPC Class Codes: F02D 41/3035 a mode being the premixed charge compression-ignition mode
• CPC Class Codes: F02D 41/401 Controlling injection timing F02D41/402 takes precedence

Abstract

In an internal combustion engine, at least one rotation variable characterizing the rotational movement of a crankshaft is ascertained cylinder-specifically. It is provided that, in an operating state in which differences and/or fluctuations of the rotation variable are basically a function of a combustion position, the instant of a fuel injection is adapted cylinder-specifically in order to reduce the differences and or fluctuations.

Claims

1-10. -10. (canceled)

11. A method for operating an internal combustion engine, comprising:

ascertaining at least one rotation variable characterizing a rotational movement of a crankshaft cylinder-specifically; and

adapting, in an operating state in which at least one of differences and fluctuations of the rotation variable are a function of a combustion position, at least one of i) an instant of a fuel injection, ii) a fresh-air volume, and iii) an exhaust-gas recirculation rate to reduce the at least one of the differences and fluctuations.

12. The method as recited in claim 11, wherein in a first step, in an initial operating state in which the at least one of the differences and fluctuations of the rotation variable are not a function of the combustion position, an injected fuel quantity is adapted cylinder-specifically to reduce the at least one of the differences and fluctuations.

13. The method as recited in claim 11, wherein the operating state includes a non-conventional operating mode, at least one of i) the operating mode having partial homogeneous mixture formation, and ii) the operating mode being a regeneration operating mode for an exhaust-gas treatment device.

14. The method as recited in claim 11, wherein based on the cylinder-specific rotation variable, a cylinder-specific combustion position or a cylinder-specific torque is ascertained as absolute value.

15. The method as recited in claim 14, wherein a torque derived from a cylinder pressure in a guide cylinder, a torque ascertained from a lambda value and an air charge, or a torque ascertained from the rotation variable is used as a reference quantity for the absolute value.

16. The method as recited in claim 15, wherein the cylinder-specific combustion position or the cylinder-specific torque is corrected to a setpoint value.

17. The method as recited in claim 16, wherein the combustion position is adjusted to at least one of a temporal and a local average value.

18. The method as recited in claim 17, wherein in order to adjust the combustion position, the difference between a cylinder-specific actual rotation variable and an actual rotation variable averaged over the cylinders is supplied directly to a controller.

19. A storage medium storing a computer program, the computer program, when executed by a control device, causing the device to perform the steps of:

ascertaining at least one rotation variable characterizing a rotational movement of a crankshaft cylinder-specifically; and

adapting, in an operating state in which at least one of differences and fluctuations of the rotation variable are a function of a combustion position, at least one of i) an instant of a fuel injection, ii) a fresh-air volume, and iii) an exhaust-gas recirculation rate to reduce the at least one of the differences and fluctuations.

20. A control device for an internal combustion engine, the control device adapted to perform the steps of:

ascertaining at least one rotation variable characterizing a rotational movement of a crankshaft cylinder-specifically; and

adapting, in an operating state in which at least one of differences and fluctuations of the rotation variable are a function of a combustion position, at least one of i) an instant of a fuel injection, ii) a fresh-air volume, and iii) an exhaust-gas recirculation rate to reduce the at least one of the differences and fluctuations.