Control strategy for NOx-accumulator

摘要

This patent develops on the method of DE19653756, where measurements are taken during individual working cycles to determine the regenerant (fuel) to be injected. In the present development, during such measurement, further parameters influencing delay, are taken into account. Preferred features: One further parameter taken into account is the formation of a wall film of fuel (especially in the inlet manifold). Another is the quantity of stored O2 in a catalyst (23) upstream of the NOx storage unit (16). The controller (19) determines regenerant measurements based on individual engine (1) cycles and a catalyst (23) is employed upstream of the NOx storage unit. Stored oxygen in the catalyst (23) is minimized. The control unit may be used with direct fuel injection into a combustion chamber.