Patent ID: 6481423
Filing Date: 2002-11-19
Classification: F02D,G01N,Y02T

Abstract:
A method of estimating a concentration of recirculated exhaust gas at an intake port of an internal combustion engine comprising the steps of:estimating a first concentration of recirculated exhaust gas in an intake manifold plenum of said engine using a dynamic model of air and exhaust gas mixing in said intake manifold plenum based on air and exhaust gas flow estimates, and delaying said first concentration to form an estimate of said concentration of recirculated exhaust gas at said intake port; estimating a second concentration of recirculated exhaust gas in said intake manifold plenum using a steady-state model of said concentration based on an estimate of exhaust gas flow into said intake manifold plenum and an estimate of total gas flow through said intake manifold plenum; and compensating said estimate of the concentration of recirculated exhaust gas at said intake port for error in said air and exhaust gas flow estimates by adjusting said first concentration based on a deviation of said first concentration from said second concentration.