Method for determining e.g. supercharging pressure, in suction tube in air supply system of internal combustion engine in engine system, involves forming difference equation for discretization of differential equation based on Euler-process

摘要

The method involves providing a differential equation with respect to an air system parameter e.g. supercharging pressure, based on measurement- and/or model factors that describe states in an air supply system (3) of an internal combustion engine (2). A difference equation for discretization of the differential equation is formed based on an implicit Euler-process, and is solved to obtain the air system parameter. The difference equation is approximated by an approximation model function that is selected so that an analytical solution of the difference equation exists. Independent claims are also included for the following: (1) a device for determining an air system parameter in an air supply system of an internal combustion engine (2) a computer program comprising instructions to perform a method for determining an air system parameter in an air supply system of an internal combustion engine.