A method for controlling the EGR and the throttle valves in an internal combustion engine

摘要

A method and system are provided for controlling a throttle valve and an EGR valve in internal combustion engine. The method includes, the steps of measuring an actual fresh mass air flow value entering the engine, determining an exhaust oxygen concentration set point indicative of the oxygen concentration in the exhaust manifold, calculating an air reference value as a function of the exhaust oxygen concentration set point ([O2]spEM) and determining an oxygen concentration feedback value representative of the oxygen concentration in the engine. The method further includes, but is not limited to the steps of obtaining a position information for the throttle valve by comparing the actual fresh mass air flow value and air reference value and obtaining a position information for the EGR valve by comparing the oxygen concentration feedback value and oxygen concentration set point. The method also includes the steps of controlling the throttle valve and the EGR valve according to the position information.