Patent ID: 9162184
Filing Date: 2015-10-20
Classification: B01D,F01N,F02B,F02D,Y02T

Abstract:
1. An exhaust gas purification system for an internal combustion engine that includes a diesel oxide catalyst (DOC) and a diesel particulate filter (DPF) for collecting particulate matter (PM) in exhaust gas in an exhaust gas passage and that treats the PM collected in the DPF to regenerate the DPF, the system comprising: a regeneration control unit controlling a temperature raising unit, when the PM has accumulated more than a predetermined amount, to heat up the DPF to around a predetermined target temperature and burn off the accumulated PM, the regeneration control unit including a feedforward controller outputting a basic variable for the temperature raising unit based on an operating condition of the internal combustion engine, a feedback controller outputting a correcting variable for achieving the target temperature of the DPF, and a variable adding unit adding the correcting variable output from the feedback controller to the basic variable output from the feedforward controller to compute a manipulated variable, the system further comprising: at least one of an integrator resetter resetting an integral value of an integrator forming the feedback controller when a sudden drop in exhaust gas flow rate is detected based on a monitored exhaust gas flow rate or a control value calculated from the exhaust gas flow rate, and a basic variable calculating unit calculating the basic variable to be output from the feedforward controller based on the exhaust gas flow rate or a control value calculated from the exhaust gas flow rate.