Method and system for estimating a midbed temperature of a catalytic converter in an exhaust system having a variable length exhaust pipe

摘要

A method and system for estimating the midbed temperature of a catalytic converter in an exhaust system of an internal combustion engine utilizes a sensor for a rotational speed of the engine and generating a corresponding speed signal. A control logic determines whether the exhaust gas is flowing through the short path or the long path, determines an instantaneous temperature of exhaust gas at a first point on the exhaust pipe based on the speed signal, and determines an instantaneous temperature at a midbed point of the catalytic converter based on the instantaneous temperature of exhaust gas at the first point on the exhaust pipe and which path the exhaust gas is flowing.