Method and system for the control of an internal combustion engine with a three-way catalyst

摘要

The invention relates to a control system and a control method for an internal combustion engine (2) with a three-way catalyst TWC (4). A lambda-controller (7) of the system controls in a closed loop the lambda-value (» c ) of the exhaust gas within or behind the TWC (4). Besides this, an oxygen-storage-controller (1) controls the internal combustion engine (2) such that the level of oxygen stored in the TWC (4) remains within predetermined limits, thus guaranteeing that the TWC (4) has enough capacity to deal with transient rich or lean deviations in the composition of the exhaust gas. The oxygen-storage-controller (1) preferably relies on a catalyst-model (6) that estimates the level ( est ) of oxygen stored in the TWC.