Patent ID: 7502683

Claim:
A device for determining an adjustable variable of a controller of an internal combustion engine having a cylinder with an associated combustion chamber, an exhaust gas tract in which an exhaust gas catalyzer and an exhaust gas probe located in the exhaust gas catalyzer are arranged, comprising: an air/fuel ratio processor that determines a specified air/fuel ratio in the combustion chamber of the cylinder as a function of an operating variable of the engine; a filter that receives the determined specified air fuel ratio and filters the specified air/fuel ratio to provide a filtered specified air/fuel ratio, wherein the filter models the dynamic behavior of the upstream area of the exhaust gas catalyzer in relation to the arrangement of the exhaust gas probe in the exhaust gas catalyzer in respect of its storage, reduction and/or oxidation behavior; a comparator that determines an air/fuel ratio in the combustion chamber of the cylinder as a function of a measuring signal of the exhaust gas probe; and a variable processor that determines the manipulated variable as a function of the filtered specified and the detected air/fuel ratio in the combustion chamber of the cylinder.