EXHAUST GAS PURIFICATION SYSTEM FOR INTERNAL COMBUSTION ENGINE

摘要

An object of the present invention is to recover the performance of an exhaust gas purification apparatus while suppressing slipping of fuel through the exhaust gas purification apparatus. When the performance of the exhaust gas purification apparatus is to be recovered at a time when the intake air quantity of the internal combustion engine is increasing (S101, S103), an upper limit value is set for the quantity of fuel added through a fuel addition valve provided in the exhaust passage (S104). If a target fuel supply quantity to be supplied to the exhaust gas purification apparatus is larger than the upper limit value (S105), a quantity of fuel quantity equal to the upper limit value is added through the fuel addition valve, and the shortfall of fuel supply is injected by sub fuel injection in the internal combustion engine (S110, S111, S112).