| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent discharge of high-concentration sulfur components when sulfur poisoning amount of an exhaust emission control catalyst of an internal combustion engine becomes excessive. <P>SOLUTION: When S components accumulate on the exhaust emission control catalyst, PM accumulation amount PMsm is increased and the frequency of lean-burn temperature increase treatment in PM regeneration control is increased (S102). As a result, the S components accumulated on the exhaust emission control catalyst are released by using the lean-burn temperature increase treatment in the PM regeneration control. Therefore, even when there is no chance to realize a sulfur poisoning recovery execution region and S poisoning becomes excessive, the lean-burn temperature increase treatment in the PM regeneration control can be performed in such a manner that excessive S components on the exhaust emission control catalyst can be released by this lean-burn temperature increase treatment. Since the S components released by the lean-burn temperature increase treatment is excessive part of the accumulated S components and the frequency of the lean-burn temperature increase treatment is high, the concentration of S components to be released can be suppressed. Accordingly, the problem is solved. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
