Determination of the internal temperature of a motor vehicle catalyzer, whereby the time delay applied to low pass filtering of measurements is adjusted according to the exhaust gas mass flow to improve temperature correlation

摘要

Method in which a continuous sample of gas is removed from the flow of exhaust gas entering the catalyzer and its temperature measured. The measured temperature signal is passed through a low-pass filter and output as an output temperature value. According to the method a time delay is determined based on the exhaust gas mass flowrate with the measured temperature values not subjected to low-pass filtering until the delay time has elapsed. The invention also relates to a corresponding device.