CONTROL METHOD OF EXHAUST EMISSION PURIFICATION SYSTEM AND EXHAUST EMISSION PURIFICATION SYSTEM

摘要

In a control method of an exhaust emission purification system (1) and the exhaust emission purification system (1), an exhaust throttle valve (14) is opened if an engine load reaches at least a predetermined first judgment value during execution of forced regeneration control with said exhaust throttle valve (14) closed when a vehicle is stopping. If the engine load thereby increases during execution of forced regeneration of a DPF (12) for purifying PM (particulate matter) in exhaust gas with the exhaust throttle valve (14) closed when the vehicle is stopping, a good combustion state can be sustained in a cylinder by opening the exhaust throttle valve (14) and taking fresh air into the cylinder of an engine (10).