CATALYST TEMPERATURE ESTIMATION DEVICE AND CATALYST ESTIMATION METHOD, ESTIMATING TEMPERATURE OF EXHAUST GAS PURIFICATION CATALYST

摘要

PURPOSE: A catalyst temperature estimation device and a catalyst estimation method are provided to exactly estimate the temperature of an exhaust gas purification catalyst. CONSTITUTION: A catalyst temperature estimation device comprises a first estimating unit(10) estimating the temperature of exhaust gas exhausted from a combustion chamber of an internal combustion engine as the normal catalyst temperature under abnormal operation of the engine, on the basis of an operation state of the engine; a second estimating unit(20) estimating the representative temperature of an inner wall of a corresponding exhaust pipe to a corresponding exhaust gas purification catalyst from the engine, on the basis of the normal catalyst temperature estimated from the first estimating unit; a third estimating unit(30) estimating the temperature of catalyst inflow exhaust gas flowing into the exhaust gas purification catalyst, on the basis of the normal catalyst temperature and the representative temperature of the inner wall of the exhaust pipe; and a fourth estimating unit(40) estimating the temperature of exhaust gas purification catalyst, on the basis of the temperature of the catalyst inflow exhaust gas.