Fuel metering control system in internal combustion engine

摘要

A system for controlling fuel metering in an internal combustion engine using a fluid dynamic model with the quantity of throttle-past air being determined therefrom. Based on the observation that the difference between the steady-state engine operating condition and the transient engine operating condition can be described as the difference in the effective throttle opening areas, the quantity of fuel injection is determined from the product of the ratio between the area and its first-order lag value and the quantity of fuel injection under the steady-state engine operating condition obtained by mapped data retrieval and by subtracting the quantity of correction corresponding to the quantity of chamber-filling air. A pseudo-manifold pressure is estimated and is used for calculating the effective throttle opening area and its first lag value. The pseudo-manifold pressure is corrected by atmospheric pressure, engine coolant water temperature, etc., so as to enhance estimation accuracy. <MATH>