System And Method For Operation Of An Internal Combustion Engine

A device for operating an internal combustion engine having a plurality of cylinders, each of which is assigned a respective injection valve, an exhaust gas section comprising an exhaust gas catalytic converter, and a lambda probe arranged upstream of or in the exhaust gas catalytic converter and generating a measurement signal, the device comprising:

• a first assignment unit to determine cylinder-specific measurement signals as a function of the measurement signal,
• an observer comprising a sensor model of the lambda probe, the sensor model arranged in a feedback branch of the observer, wherein the cylinder-specific measurement signals are fed to the observer on an input side, and observer output variables related to the respective cylinders are available on the output side,
• a calibration unit operable:
• to impress a predefined interference pattern made of cylinder-specific mixture differences, and
• to adapt, in reaction to the respectively predefined interference pattern as a function of the observer output variables related to the respective cylinders, an assignment rule between the measurement signal of the lambda probe and a lambda signal,
• a second assignment unit to carry out, by means of the assignment rule, an assignment between the measurement signal and the lambda signal.