ROTATIONAL SPEED-BASED ESTIMATION OF THE AIR/FUEL RATIO OF THE CYLINDER IN A SINGLE-CYLINDER INTERNAL COMBUSTION ENGINE

摘要

The invention relates to a method for estimating an air/fuel ratio for a combustion in an internal combustion engine with at least one cylinder. The air/fuel ratio is derived from a feature which is based on an evaluation of a rotational speed of a crankshaft of the internal combustion engine. The feature is calculated from at least one rotational speed value from at least one range of the compression phase and from at least one rotational speed value from at least one range of the combustion phase of the at least one cylinder of the internal combustion engine, wherein the calculation of the feature is carried out while incrementally varying a fuel quantity supplied to the internal combustion engine. The invention further relates to a corresponding arrangement.