Closed loop diesel engine EGR control including event monitoring

摘要

A control system and method for an EGR valve, particularly in a diesel engine. A processor processes data in feedback control of the position of the valve element to develop from the data a position control signal for setting the extent to which the valve is open. The processing includes processing data corresponding to actual position of the valve and data representing a desired position of the valve to develop a position error signal, processing data that defines actual EGR rate and data representing a desired EGR rate to develop a rate error signal, and processing the position error signal and the rate error signal to develop the position control signal. Emission control system event monitors flag potential error sources in their incipiency to afford opportunity for correction before mandatory logging occurs.