Patent attributes
A drive unit of a motor vehicle, provided with an internal combustion engine, with a combustion air supply having a low-pressure compressor, a high-pressure compressor and a combustion air cooling unit, and with an exhaust gas withdrawal via which exhaust gas formed in the internal combustion engine is withdrawn. The drive unit has a cooling system with at least one cooling circuit in which are arranged a heat exchanger, through which flows a working medium and which can be cooled by atmospheric air, at least one exhaust gas cooler integrated into the exhaust gas withdrawal, and the combustion air cooling unit has a combustion air intercooler and a main combustion air cooler that are thermally coupled to the cooling circuit in such a way that in the direction of flow of combustion air, the combustion air intercooler is disposed between the low-pressure and the high-pressure compressors, and the main combustion air cooler is disposed downstream of the high-pressure compressor. At least one first cooling circuit and one second cooling circuit are provided that are hydraulically uncoupled via at least one heat exchanger, via which the first and the second cooling circuits are in thermal contact. For a working medium contained in the second cooling circuit an at least partial phase transition can be brought about during an operating phase of the cooling system.
