Patent ID: 6655129
Filing Date: 2003-12-02
Classification: F02D,Y02T

Abstract:
A process for operating a three-way catalyst located in an exhaust gas line by regulating an air/fuel mixture supplied to an internal combustion engine, wherein said three-way catalyst comprises an oxygen storage component and said oxygen storage component comprises a minimum filling degree and a maximum filling degree for oxygen and said oxygen storage component further comprises a set-point interval, said process comprising:a. initiating a test phase, wherein said test phase comprises applying a pulse sequence to change a filling degree of the oxygen storage component, wherein said filling degree has an initial value and said pulse sequence either enriches or reduces the richness of the air/fuel mixture supplied to the engine by a certain amount to raise or lower said initial value and returns the filling degree to said initial value by applying a pulse in the opposite direction; b. determining whether there was a breakthrough of lean or rich exhaust gas through the catalyst during said pulse sequence; and c. if a breakthrough is detected, adjusting the air/fuel mixture such that the filling degree is adjusted to be within said set-point interval.