| 摘要 |
<p>PURPOSE: To estimate a catalyst temperature with high accuracy on the basis of an engine operating condition. CONSTITUTION: A time constantτis set on the basis of an intake air amount as that the intake air amount corresponds to a catalyst flow-in exhaust amount (S7), The estimating value of a catalyst temperature is following-changed against change of an operating condition on the basis of the time constantτ(∫4). When a low load standard operation is transferred from a condition (S8) which is continued for a prescribed time or more into excessive operation, following change of an estimating value corresponding to excessive operation is inhibited for a prescribed time (S12), and thereby, the catalyst temperature can be estimated corresponding to temperature raising delay caused by heat mass of the catalyst.</p> |
