Method and apparatus for determining and regulating an exhaust gas recirculation rate of an internal combustion engine

摘要

The invention relates to a method and an apparatus for determining an exhaust gas recirculation rate in an internal combustion engine, in which the exhaust gas recirculation rate indicates a proportion of exhaust gas in a gas quantity delivered to a cylinder of the internal combustion engine, and combustion takes place in the cylinder of the engine cyclically during a combustion phase. The method includes the steps of ascertaining a combustion course statement over the course of combustion in the cylinder of the engine, and ascertaining an actual exhaust gas recirculation rate from the combustion course statement with the aid of a predetermined exhaust gas recirculation rate function. The invention further relates to a method and an apparatus for regulating an exhaust gas recirculation rate in an internal combustion engine, in which the exhaust gas recirculation rate indicates a proportion of exhaust gas in a gas quantity delivered to a cylinder of the internal combustion engine, and combustion takes place in the cylinder of the engine cyclically during a combustion phase. The method includes the steps of ascertaining a combustion course statement over the course of combustion in the cylinder of the engine, furnishing a set-point statement as a function of an operating point of the engine, and performing a regulation to compensate for a deviation that results from the set-point statement and the combustion course statement.

主权项

1. A method for regulating an exhaust gas recirculation rate in an internal combustion engine, which rate indicates a proportion of exhaust gas in a gas quantity delivered to a cylinder of the internal combustion engine, and combustion takes place in the cylinder of the engine cyclically during a combustion phase, having the following steps:
ascertaining a combustion course statement that characterizes a course of combustion in the cylinder of the engine, wherein the combustion course statement is ascertained by measuring a combustion chamber pressure in the cylinder; furnishing a set-point statement as a function of an operating point of the engine; and performing a regulation of the exhaust gas recirculation rate to compensate for a deviation between a set-point value indicated by the set-point statement and an actual value that is one of indicated by and derived from the combustion course statement.