A method for estimating the stoichiometric ratio for a control system of an internal combustion engine

摘要

A method for estimating the stoichiometric ratio of fuel for a control system of an internal combustion engine including an oxygen sensor (4, 26) disposed along an exhaust duct (6) and supplying a composition signal (V lambda ) and a control unit (5, 27) which includes a controller (10, 30) supplying a control parameter (KO2) as a function of an error magnitude (VE, lambda E) and an estimation block (15, 31) receiving a filtered control parameter (KO2F) correlated with the control parameter (KO2), and supplying a real stoichiometric ratio (A/F)F. The method includes the stages of: detecting a course of the filtered control parameter (KO2F) (120-150, 220, 240) and calculating the real stoichiometric ratio (A/F)F as a function of the course detected (160).