NOX SEONSOR COMPENSATION METHOD FOR EXHAUST GAS

摘要

PURPOSE: A method for correcting an NOx(Nitrogen Oxide) sensor for exhaust gas is provided to improve the purification efficiency of the NOx by spraying urea using an exactly estimated concentration of the NOx. CONSTITUTION: A method for correcting an NOx(Nitrogen Oxide) sensor for exhaust gas is as follows. The degradation factors of catalysts are selected (S710). A ratio of NOx generated form the catalysts to NO2 is corrected firstly according to the degradation factors(S740). The ratio of the NOx to the NO2 is corrected secondly according to amount of PM(Particulate Matters) collected in the catalysts. The final ratio of the NO2 is selected. NOx sensing signals delivered from a NOx sensor, which is installed in exhaust lines are outputted (S780). The final NOx amount is selected by using the final ratio of the NO2 and the NOx sensing signals. (S790).