Abstract: The invention relates to a fuel cell system (1) comprising an air compressor (5) which is used to compress an air mass flow (4) that is supplied to at least one fuel cell (3), and further comprising a cooling air path (19), via which a cooling air mass flow (7) is branched off from the compressed air mass flow (6). The cooling of the air compressor (5) in the fuel cell system (1) is further improved by an on-demand control (20) of the compressed cooling air mass flow (6).

Abstract: A fuel-cell system has at least one fuel cell, an oxidant line, a compressor, an exhaust-air line, a turbine, which is arranged in the exhaust-air line and is coupled to the compressor, an anode-purging line, which is connected to the exhaust-air line and has an anode-purging valve, and a control unit.

Abstract: The invention relates to a radial compressor (1) comprising at least one impeller wheel (3), which is driven rotatably in a compressor housing (2) and has a wheel front side (5) and a wheel rear side (6), the wheel front side (5) being intended to convey a mass flow (13) by means of a number of blades (7), the wheel rear side (6) of the impeller wheel (3) having a blading (8) by means of which a second pressure distribution (12) is generated on the wheel rear side (6) of the impeller wheel (3) during operation of the radial compressor (1), which second pressure distribution counteracts a first pressure distribution (11) on the wheel front side (5) in order to reduce an axial force that is to be braced in the compressor housing (2).

Abstract: The invention relates to a fuel cell system (1) comprising an air compressor (5) which is used to compress an air mass flow (4) that is supplied to at least one fuel cell (3), and further comprising a cooling air path (19), via which a cooling air mass flow (7) is branched off from the compressed air mass flow (6). The cooling of the air compressor (5) in the fuel cell system (1) is further improved by an on-demand control (20) of the compressed cooling air mass flow (6).

Abstract: Turbomachine (10), in particular for a fuel cell system (1). The turbomachine (10) comprises a compressor (11), a drive device (20) and a shaft (14). The compressor (11) has a rotor (15) arranged on the shaft (14), a compressor inlet (11a) and a compressor outlet (11b). A working fluid can be delivered from the compressor inlet (11a) to the compressor outlet (11b). A drive cooling path (92) for cooling the drive device (20) branches off at the compressor outlet (11b). Also proposed is a fuel cell system (1) with a turbomachine (10) according to the invention, a method for operating the turbomachine (10) and a method for operating the fuel cell system (1).

Abstract: Turbomachine (10), in particular for a fuel cell system (1). The turbomachine (10) comprises a compressor (11), a drive device (20) and a shaft (14). The compressor (11) has a rotor (15) arranged on the shaft (14), a compressor inlet (11a) and a compressor outlet (11b). A working fluid can be delivered from the compressor inlet (11a) to the compressor outlet (11b). A drive cooling path (92) for cooling the drive device (20) branches off at the compressor outlet (11b). Also proposed is a fuel cell system (1) with a turbomachine (10) according to the invention, a method for operating the turbomachine (10) and a method for operating the fuel cell system (1).