AN INTERNAL COMBUSTION ENGINE SYSTEM

The invention relates to an internal combustion engine system (1) comprising: an internal combustion engine (2); a turbocharger turbine (5) operatively connected to a turbocharger compressor (6); an air intake system (7); an exhaust gas system (8); an exhaust gas recirculation (EGR) conduit (10); an EGR valve (13); and a turbomachine (9) arranged in the EGR conduit (10). Further, the EGR valve (13) and the turbomachine (9) are positioned in relation to each other in the EGR conduit (10) such that a flow of high pressure exhaust gas through the EGR conduit (10) towards the air intake system (7) reaches the EGR valve (13) before reaching the turbomachine (9); an additional exhaust gas conduit (16) is arranged between the EGR conduit (10) and a point (17) of the exhaust system (8) downstream the turbocharger turbine (5) so as to allow exhaust gas to flow between the EGR conduit (10) and the point (17) downstream the turbocharger turbine (5) without passing through the turbocharger turbine (5), wherein the additional exhaust gas conduit (16) is connected to the EGR conduit (10) at a point (17) between the EGR valve (13) and the turbomachine (9) so as to provide a communication between the turbomachine (9) and the additional exhaust gas conduit (16) even if the EGR valve (13) is closed; and an additional exhaust valve (18) is arranged in connection with the additional exhaust gas conduit (16) so as to provide for regulation of a flow of gas through the additional exhaust gas conduit (16). The invention also relates to a method for operating such an engine system.