A METHOD FOR CONTROLLING A TURBOCHARGER SYSTEM WITH A PRESSURIZED GAS TANK CONNECTED TO AN EXHAUST MANIFOLD OF A COMBUSTION ENGINE

A method for controlling a turbocharger system fluidly connected to an exhaust manifold of a combustion engine and an exhaust after treatment system. The turbocharger system comprises a turbocharger turbine operable by exhaust gases from the exhaust manifold, and a tank with pressurized gas, the tank being fluidly connectable to the turbocharger turbine. The method comprises the steps of: determining a NOx parameter being indicative of, or correlated to, NOx emissions from the exhaust after treatment system; and injecting pressurized gas from the tank to drive the turbocharger turbine based on the determined NOx parameter, wherein a determined NOx parameter above a pre-defined first threshold determines that pressurized gas from the tank is injected.