Abstract: A method for monitoring a regulated emissions concentration C, in the exhaust gas of an internal combustion engine is provided. The method comprises directing the exhaust gas through an exhaust-gas turbocharger, directing at least a portion of the exhaust gas through an exhaust-gas recirculation system, measuring an air ratio ?meas in the exhaust gas with a lambda probe, measuring a rotational speed nT of the exhaust-gas turbocharger with a sensor, and determining the regulated emission concentration Ci based on the air ratio ?meas and the rotational speed nT. In this way, the emission concentration of the exhaust may be determined as a function of the rotational speed of the turbine.

Abstract: The disclosure relates to a method for controlling a turbocharger system of an internal combustion engine. The method comprises controlling a first bypass valve of a high pressure exhaust gas turbine and a second bypass valve of a low pressure gas turbine on the basis of a turbine model, the first and second bypass valves continuously variable. In this way, turbocharger system efficiency may be maximized.

Abstract: The present application relates to a method for determining the exhaust back pressure p3 upstream of a turbine, which is arranged in the exhaust line of an internal combustion engine equipped with an engine management system (1), which exhaust line is intended to lead off the exhaust gas from a number cylinders of the internal combustion engine. The method includes determining the exhaust back pressure p3 upstream of a turbine, by means of which the exhaust back pressure p3 can still be determined precisely but at little cost compared to methods known in the state of the art.

Abstract: The present application relates to a method for determining the exhaust back pressure p3 upstream of a turbine, which is arranged in the exhaust line of an internal combustion engine equipped with an engine management system (1), which exhaust line is intended to lead off the exhaust gas from a number cylinders of the internal combustion engine. The method includes determining the exhaust back pressure p3 upstream of a turbine, by means of which the exhaust back pressure p3 can still be determined precisely but at little cost compared to methods known in the state of the art.