Method for operating an internal combustion engine in an idle mode

Patent metadata

Field	Value
Publication number	US-9932915-B2
Application number	US-201414482762-A
Country	US
Kind code	B2
Filing date	Sep 10, 2014
Priority date	Sep 12, 2013
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

A method for operating an internal combustion engine in an idle mode, in which an ignition angle and/or an air quantity of the internal combustion engine is influenced and/or is modified as a function of an idle rotation speed of the internal combustion engine. The ignition angle and/or the air quantity and/or a fuel quantity for at least one combustion chamber of the internal combustion engine is modified as a function of at least one variable characterizing a combustion event in the combustion chamber.

First claim

What is claimed is:

1. A method for operating an internal combustion engine having a plurality of combustion chambers, the method comprising: performing, during an idle mode of the internal combustion engine after a cold start of the internal combustion engine, the following: at least one of influencing and modifying at least one of an ignition angle, an air quantity, and a fuel quantity for at least one of the combustion chambers of the internal combustion engine as a function of an idle rotation speed of the internal combustion engine, and as a function of at least one variable characterizing a combustion event in the at least one of the combustion chambers, wherein at least one variable that corresponds to the ignition angle, a modified ignition angle, the air quantity, a modified air quantity, the fuel quantity, and a modified fuel quantity, is stored in an individual-cylinder manner in a data memory for individual-cylinder pilot control of the ignition angle; providing a first control loop, in which the variable characterizing the combustion event is controlled in a closed-loop manner by the ignition angle, wherein the first control loop receives a setpoint combustion location and an actual combustion location as inputs and modifies the ignition angle based at least partially on a difference between the actual combustion location and the setpoint combustion location; providing a second control loop in which the idle rotation speed of the internal combustion engine is controlled in a closed-loop manner by at least one of the air quantity and the quantity of fuel injected, wherein the second control loop receives a setpoint idle rotation speed and an actual idle rotation speed as inputs and modifies the idle rotation speed based at least partially on a difference between the actual idle rotation speed and the setpoint idle rotation speed, and wherein the second control loop is different from the first control loop; operating the first control loop and the second control loop as a function of one another; and reducing one or more deviations between the combustion chambers of the internal combustion engine by, in a subsequent idle mode after a subsequent cold start of the internal combustion engine, using the at least one stored variable in the data memory to perform the individual-cylinder pilot control of the ignition angle, wherein a further modification of the ignition angle is accomplished for a definable time interval by an open-loop control system.

2. The method of claim 1 , wherein the variable characterizing the combustion event includes at least one of a combustion location, an average combustion chamber pressure, and an onset of the combustion event.

3. The method of claim 1 , wherein the variable characterizing the combustion event is determined from at least one of a combustion chamber pressure, a time course of the combustion chamber pressure, a time course of the idle rotation speed, and determining an ionization current.

4. The method of claim 1 , wherein the method is carried out in an individual cylinder manner for at least one of the combustion chambers of the internal combustion engine.

5. The method of claim 1 , wherein the air quantity is modified by at least one of a throttle valve and an opening duration of an intake valve.

6. The method of claim 1 , wherein at least one of the first control loop and the second control loop are operated in consideration of one or more definable interference variables.

7. The method of claim 1 , wherein a variance of the variable characterizing the combustion event is determined, and wherein the ignition angle is modified as a function of the determined variance.

8. The method of claim 1 , wherein a further modification of the ignition angle is modified for a definable time interval as a function of further variables characterizing an operating state of the internal combustion engine, the further variables being used alone or in addition to a combustion chamber pressure and the idle rotation speed.

9. The method of claim 1 , wherein the modification of the ignition angle occurs in steps of approximately 0.25 degrees of a crankshaft angle.

10. An open-loop and/or closed-loop control device for an internal combustion engine having a plurality of combustion chambers, the control device comprising: a program code arrangement having program code for operating an internal combustion engine by performing, during an idle mode of the internal combustion engine after a cold start of the internal combustion engine, the following: at least one of influencing and modifying at least one of an ignition angle, an air quantity, and a fuel quantity for at least one of the combustion chambers of the internal combustion engine as a function of an idle rotation speed of the internal combustion engine, as a function of at least one variable characterizing a combustion event in the at least one of the combustion chambers, wherein at least one variable that corresponds to the ignition angle, a modified ignition angle, the air quantity, a modified air quantity, the fuel quantity, and a modified fuel quantity, is stored in an individual cylinder manner in a data memory for individual-cylinder pilot control of the ignition angle; providing a first control loop, in which the variable characterizing the combustion event is controlled in a closed-loop manner by the ignition angle, wherein the first control loop receives a setpoint combustion location and an actual combustion location as inputs and modifies the ignition angle based at least partially on a difference between the actual combustion location and the setpoint combustion location; providing a second control loop, in which the idle rotation speed of the internal combustion engine is controlled in a closed-loop manner by at least one of the air quantity and the quantity of fuel injected, wherein the second control loop receives a setpoint idle rotation speed and an actual idle rotation speed as inputs and modifies the idle rotation speed based at least partially on a difference between the actual idle rotation speed and the setpoint idle rotation speed, and wherein the second control loop is different from the first control loop; operating the first control loop and the second control loop as a function of one another and reducing one or more deviations between the combustion chambers of the internal combustion engine by, in a subsequent idle mode after a subsequent cold start of the internal combustion engine, using the at least one stored variable in the data memory to perform the individual-cylinder pilot control of the ignition angle, wherein a further modification of the ignition angle is accomplished for a definable time interval by an open-loop control system.

11. A non-transitory computer readable medium having a computer program, which is executable by a processor, comprising: a program code arrangement having program code for operating an open-loop and/or closed-loop control device for an internal combustion engine having a plurality of combustion chambers by performing, during an idle mode of the internal combustion engine after a cold start of the internal combustion engine, the following: at least one of influencing and modifying at least one of an ignition angle, an air quantity, and a fuel quantity for at least one of the combustion chambers of the internal combustion engine as a function of an idle rotation speed of the internal combustion engine, as a function of at least one variable characterizing a combustion event in the at least one of the combustion chamber chambers, wherein at least one variable that corresponds to the ignition angle, a modified ignition angle, the air quantity, a modified air quantity, the fuel quantity,

Assignees

• Bosch Gmbh Robert

Inventors

• Gaenzle David
• Fischer Wolfgang
• Nack Laurent

Classifications

• F02D41/008

  Controlling each cylinder individually · CPC title

• F02D41/16

  for idling · CPC title

• F02D31/008

  for idle speed control · CPC title

• F02D35/023

  by determining the cylinder pressure · CPC title

• F02D35/028

  by determining the combustion timing or phasing · CPC title