METHOD OF CONTROLLING EXHAUST GAS PURIFICATION SYSTEM, AND EXHAUST GAS PURIFICATION SYSTEM

摘要

In an exhaust gas temperature raising control for recovering purification ability of an exhaust gas purification device (12) of an internal combustion engine, the exhaust gas temperature is efficiently raised to a target level with white smoke prevented from being produced. To achieve this, in the exhaust gas temperature raising control in recovery control of the exhaust gas purification device (12), when the temperature (Tg1) of the exhaust gas flowing into the exhaust gas purification device (12) is lower than a predetermined judgment value (Tp), a first exhaust gas temperature raising control that does not include post injection but includes intake air restriction is performed, and when equal to or higher than the predetermined judgment value (Tp), a second exhaust gas temperature raising control that includes both the post injection and the intake air restriction is performed to set an intake air restriction amount (±) in the first exhaust gas temperature raising control greater than an intake air restriction amount (²) in the second exhaust gas temperature raising control.