A METHOD FOR CONTROLLING AN INTERNAL COMBUSTION ENGINE SYSTEM

A method for controlling an internal combustion engine system (1) so as to avoid turbo surge and/or shorten power cut off during gearshift, wherein the internal combustion engine system (1) comprises: an internal combustion engine (2) and a gearbox (3) operatively connected to the internal combustion engine (2); a turbocharging arrangement (4) configured to provide a boost pressure of air fed to the internal combustion engine (2); and a control system (5) configured to control operation of the internal combustion engine system (1), the method comprising: providing information about i) a point of time for initiating an upcoming gearshift (ti), ii) a target engine speed after the upcoming gearshift, iii) a target engine torque after the upcoming gearshift, and iv) current operation conditions of the internal combustion engine system (1); determining, based on said information and before the upcoming gearshift is initiated, whether there is a risk of having turbo surge during the upcoming gearshift; and, if such a risk is determined, lowering the boost pressure before initiating the upcoming gearshift.