Exhaust gas recirculation control system for internal combustion engines

摘要

An exhaust gas recirculation control system for internal combustion engines, comprising an exhaust gas recirculation passage for recirculating a part of an exhaust gas from an internal combustion engine into the engine; an exhaust gas recirculation control valve for controlling a flow rate of the exhaust gas flowing in the exhaust gas recirculation passage; an opening degree controller for controlling an opening degree of the exhaust gas recirculation control valve; an operating condition detector for detecting an operating condition of the engine; means for setting a target exhaust gas recirculation ratio depending on the detected operating condition; a combustion state detector for detecting a combustion state in at least one cylinder of the engine; means for finding an actual exhaust gas recirculation ratio of the engine based on the detected combustion state; and means for controlling the opening degree controller so as to bring the actual exhaust gas recirculation ratio to the target exhaust gas recirculation ratio.