Method of controlling an adaptive desulphation process for an internal combustion engine

摘要

A method of controlling an adaptive desulphation process in an exhaust system of an internal combustion engine, the exhaust system comprising a lean NOx trap. The method comprises calculating S640 a desulphation index 640, whose value correlates to or is proportional to the need of desulphation of the lean NOx trap, estimating S65) a desulphation index threshold 650, as a function of a number of forced desulphation over vehicle lifetime 645, and requesting a desulphation process S660 if said desulphation index is larger than S655 said desulphation index threshold. The desulphation index may be based on a sulphur load 600, a soot load 610, a mission profile 620, ambient temperature 631 and ambient pressure 634. The desulphation index threshold may depend on a desulphation model error, which may be a counter of error-effected desulphation rich events.