AIR-FUEL RATIO CONTROLLER OF INTERNAL COMBUSTION ENGINE

摘要

An air-fuel ratio control apparatus according to the present invention estimates, on the basis of an exhaust air-fuel ratio of exhaust gas flowing into an exhaust purifying catalyst unit 19 disposed in an exhaust passage 7 of an engine 1, an emission of at least one specific component contained in exhaust gas flowing out of the exhaust purifying catalyst unit. The air-fuel ratio control apparatus performs the estimation by use of a model, and controls the air-fuel ratio in such a manner that the estimation value reach es a target state. The model is previously determined in consideration of the mass balance of the specific component.