Patent ID: 6751947
Filing Date: 2004-06-22
Classification: F01N,F02D

Abstract:
A system for deriving an air/fuel adjustment control signal for an internal combustion engine coupled to an exhaust system having at least one catalyst, the system comprising:an oxidant set point generator that is responsive to at least one engine operating parameter to determine a target oxidant level in the catalyst; a current oxidant level estimator that is responsive to at least one engine operating parameter, and that estimates a current amount of oxidants stored in the catalyst, said current oxidant level estimator selectively determining an amount of oxidants available for being stored in the catalyst and an amount of oxidants required to oxidize hydrocarbons being produced by the engine based on an engine air/fuel ratio; and an oxidant level/capacity controller that is responsive to said target oxidant level and said current amount of oxidants stored in the catalyst, determines a difference between said target level and said current amount, and that determines a fuel injection adjustment control signal based on said difference between said target level and said current amount.