摘要 |
<p>A piston internal combustion engine with two-stage supercharging in which two exhaust gas turbocharger groups consisting each of a high pressure and low pressure exhaust gas turbocharger, supply the piston internal combustion engine with charging air. One exhaust gas turbocharger group is constructed to be connected and disconnected, whereby a closure device is arranged in the exhaust gas line of the high pressure exhaust gas turbocharger and a check valve is arranged in the suction line of the low pressure exhaust gas turbocharger. For connecting and disconnecting the exhaust gas turbocharger group at partial load, the cross section of the closure devices is controlled. In order to avoid nonpermissive excess rotational speeds in the rotating parts of the high pressure exhaust gas turbocharger during a connecting operation, charging air is conducted back from the pressure side to the suction side by way of a controllable bypass line between the suction and pressure line of the high pressure compressor. The bypass line is controlled by a further closure device in dependence on the opening of the charging air closure device.</p> |