| 摘要 |
The disclosed exhaust-gas purification system can accurately control exhaust-pipe injection with PID control during automatic regeneration while driving, even with repeated acceleration/deceleration and even if an exhaust brake valve is closed. A DPD (25) is attached to the exhaust pipe (20) of a diesel engine (10), and when said DPD (25) undergoes automatic regeneration, the exhaust-gas temperature is detected and the deviation between the detected exhaust-gas temperature and a regeneration target temperature is calculated. When using said deviation to perform PID control on the exhaust-pipe injection amount, exhaust-pipe injection is stopped if an exhaust brake valve (24) is closed during automatic regeneration while driving, computation of the integral control term of the PID control is continued while the exhaust brake valve (24) remains closed, and the continuously-computed integral control term is used as the initial manipulation amount when the exhaust brake valve (24) is opened. |
