Method for the detection of the concentration of NOx in exhaust gas

摘要

A process determines the nitrogen oxides (NOx) content in automotive exhaust gases using a sensor which registers non-stationary fluctuations at pre-determined intervals, generating a signal which is characteristic of the variation. This signal is used to regulate the operation of a NOx filter and form a signal with reduced fluctuations. This signal is used to correct the NOx signal. The sensor primarily measures the presence of unburned oxygen in exhaust gases using the lambda value, preferably a two-point or broad-band lambda signal. The condition is measured in accordance with the lambda value rate of change.