Method for controlling egr means in a combustion engine, using nox sensing means in an open-loop egr control set-up without any egr measurement device

摘要

The present invention provides for a system for controlling EGR means in a combustion engine, using NOx sensing means (7') in an open-loop EGR control set-up without any EGR measurement device and NOx estimating means (6'). The systems carries out the following steps: obtaining NOx measured value obtained from said NOx sensing means (7'), estimating NOx value obtained from said NOx estimating means (6'), calculating an error as difference between said first NOx measured value and said second NOx estimated value, controlling/correcting feed-forwardly said EGR means such that said error converges to zero.