Patent ID: 6732723
Filing Date: 2004-05-11
Classification: F02B,F02D,F02M,Y02T

Abstract:
A method for controlling EGR rate of an internal combustion engine, such engine having an intake throttle for controlling mass flow to an intake of the engine and an EGR valve for controlling flow from the exhaust of the engine back to the intake of the engine along with air passing through the intake throttle, such method comprising:measuring a mass air flow passing to the intake throttle; comparing such measured mass air flow with a desired mass air flow; producing an error signal representative of a difference between the measured mass air flow and the desired mass air flow; producing a pair of control signals in response to such produced error signal; using one of the pair of control signals to adjust the intake throttle to control mass air flow through such intake throttle; using the other one of the pair of control signals to adjust EGR rate through the EGR valve; and wherein the pair of control signals operate the intake throttle and the EGR valve to drive the error signal to a null.