Patent ID: 8489307

Claim:
A method for operating an internal combustion engine with an intake tract, in which a switching device for modifying at least one of an effective intake pipe length and an effective intake tract volume is arranged, the method comprising the steps of: with the switching device positioned in a first switching position, controlling an operational aspect of the internal combustion engine based on a dynamic model of the intake tract, which accounts for adaptive adjustments of a trimming value, by: using a dynamic model of the intake tract, determining an estimated value of a load parameter dependent on at least one operating quantity of the internal combustion engine, the load parameter selected from the group consisting of an intake pipe pressure and an air mass flow, adapting the dynamic model dependent on the trimming value, which is adaptively adjusted dependent on the estimated value of the load parameter and a measured value of the load parameter, in response to detecting a control instruction to modify the switching position of the switching device, determining an actual switching position of the switching device by a position determination process during which the trimming value is held constant, the position determination process including: determining an estimated old position value of the load parameter dependent on the model, wherein the first switching position of the switching device is assumed and adaptive adjustment of the trimming value is prevented, determining an estimated new position value of the load parameter dependent on the model, wherein a second switching position of the switching device is assumed and adaptive adjustment of the trimming value is prevented, and performing a correlation check of the estimated value of the load parameter and the estimated new position value of the load parameter with respect to the measured value of the load parameter to determine the actual switching position of the switching device; and after determining the actual switching position of the switching device by the process during which the trimming value is held constant, controlling the operational aspect of the internal combustion engine based on the dynamic model of the intake tract and the determined actual switching position of the switching device, and again accounting for adaptive adjustments of the trimming value.