DOSING CONTROL UNIT AND METHOD IN ORDER TO DOSING OF THE UREA AQUEOUS SOLUTION TO SELECTIVE CATALYTIC REDUCTION

摘要

The present invention relates to an apparatus for injecting an urea solution of a selective catalytic reduction catalyst and a method therefor. According to the present invention, the apparatus for injecting an urea solution of a selective catalytic reduction catalyst and the method therefor estimates concentration of nitrogen oxides and corrects the concentration of the nitrogen oxides estimated by a nitrogen oxides quantity correction map although a nitrogen oxides detection sensor detecting nitrogen oxides (NOx) included in an exhaust gas is in an abnormal state due to malfunction. The present invention decides an optimal urea solution injection quantity based on the corrected concentration of the nitrogen oxides (ppm) in order to enable the urea solution injection quantity optimized to the actual concentration of the nitrogen oxides of the current situation to be injected.