| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent an NOx amount exhausted from an internal combustion engine from changing by a variation in an EGR ratio when deceasing a flow of an exhausted gas passing through an exhaust emission control device by means of decreasing an opening degree of an intake air throttling valve or an exhaust air throttling valve which are provided in an exhaust passage of the internal combustion engine. <P>SOLUTION: In a PM regeneration process for a filter, estimated is an EGR rate obtained when having changed an intake air throttling opening degreeθin and an exhaust air throttling opening degreeθex into target opening degreesθinT andθexT, respectively which are at a closing side (S105). Then, an EGR opening degreeθr is changed into a target EGR opening degreeθrT in order to keep the EGR rate R at a target EGR rate RT depending on a driving state. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
