Internal combustion engine control

摘要

Internal combustion engine air/fuel ratio control provides for individual engine cylinder air/fuel ratio balancing through sensing of individual cylinder air/fuel ratio and through comparison of sensed individual cylinder air/fuel ratio to a target air/fuel ratio with air/fuel ratio control command correction prescribed on a cylinder-by-cylinder basis. The target air/fuel ratio may be determined as an overall average cylinder actual air/fuel ratio. An additional control loop is provided for driving a value representing overall engine air/fuel ratio toward a desired air/fuel ratio, such as the stoichiometric ratio. Correction values are learned gradually for each engine cylinder and stored and recalled as a function of an engine operating level.