Method for initiating and maintaining a substoichiometric operating mode of an internal combustion engine and internal combustion engine for carrying out a method of this kind

摘要

The present disclosure describes systems and methods for recharging a storage catalyst of an internal combustion engine. A method is described, comprising: while operating an engine in a substoichiometric operating mode when the engine is under medium load and responsive to an LNT condition, assisting the engine with an electric machine connected to an engine crankshaft. The electric machine provides an auxiliary drive to assist the engine in maintaining the substantially steady state substoichiometric operating mode which may be used to reduce NOx or SOx build up in a storage catalytic convertor or to assay the condition of a storage catalytic convertor.

主权项

1. A method, comprising:
initiating and maintaining a substoichiometric operating mode of an internal combustion engine with a constant air ratio λ, wherein,
the internal combustion engine has an exhaust gas discharge system for discharging exhaust gases and at least one exhaust gas aftertreatment system arranged in the exhaust gas discharge system; andswitching the internal combustion engine to a substoichiometric operating mode for a specifiable period of time, wherein,
the internal combustion engine is switched to a substoichiometric steady-state operating mode in an intermediate load range; andconnecting an electric machine to a crankshaft of the internal combustion engine to be used as a selectable auxiliary drive, when operating the internal combustion engine in the substoichiometric steady-state operating mode and the intermediate load range in which the internal combustion engine is switched to the steady-state operating mode comprises loads between 30% and 70% of a maximum load at the prevailing engine speed.