EXHAUST GAS PURIFICATION SYSTEM OF INTERNAL COMBUSTION ENGINE

摘要

An exhaust gas purification system of an internal combustion engine according to the present invention includes: processing means for executing at least one of a process of increasing an air-fuel ratio of an air-fuel mixture burned in the internal combustion engine and a process of increasing EGR gas recirculated by an EGR apparatus, when increasing a NO2 proportion in exhaust gas; and control means for controlling the processing means so that an increase in the air-fuel ratio becomes larger, and an increase in the EGR gas becomes smaller when a temperature of the exhaust gas purification apparatus is high as compared to when the temperature of the exhaust gas purification apparatus is low.

主权项

1. An exhaust gas purification system of an internal combustion engine, comprising:
an exhaust gas purification apparatus which is arranged in an exhaust passage of the internal combustion engine and which includes a selective catalytic reduction catalyst; an EGR apparatus which recirculates a part of exhaust gas flowing through the exhaust passage as EGR gas; and a controller comprising at least one processor configured to, when increasing a NO2 proportion that is a proportion of nitrogen dioxide in NOx contained in the exhaust gas, execute both or one of a process of increasing an air-fuel ratio of an air-fuel mixture burned in the internal combustion engine and a process of increasing EGR gas recirculated by the EGR apparatus so that an increase in the air-fuel ratio becomes larger and an increase in the EGR gas becomes smaller when a temperature of the exhaust gas purification apparatus is high as compared to when the temperature of the exhaust gas purification apparatus is low.