SYSTEMS, METHODS, AND APPARATUS FOR REDUCTANT DOSING IN AN SCR AFTERTREATMENT SYSTEM

摘要

Systems, methods and apparatus disclosed that include an internal combustion engine and an exhaust system that includes an exhaust aftertreatment system with an SCR catalyst. A NO_x sensor downstream of the SCR catalyst is provided along with techniques for estimating an amount of NO_x and NH3 at the tailpipe to decouple the impact of cross-sensitivity of the NO_x sensor to NO_x and NH3. Feedback control of the reductant dosing amount based on these estimates is also provided.