Abstract: The invention relates to a fuel cell system comprising: a fuel cell arrangement having at least one fuel cell and an air inlet, a feed line connected to the air inlet, a central air filter device which is connected to an inlet of the feed line either directly or via a distributor block, and a compressor which is located in the feed line and which is designed to suck in ambient air through the central air filter device and to convey said air through the feed line to the air inlet of the fuel cell arrangement. The invention also relates to a decentralized air filter system, which is designed to filter, downstream of the central filter device, air conveyed from the compressor to the air inlet. The decentralized air filter system comprises at least one decentralized air filter device which is located in the feed line between the compressor and the air inlet of the fuel cell arrangement, in the distributor block, or in the central air filter device.

Abstract: The invention relates to a fuel cell system (100) with at least one fuel cell (90), each fuel cell (90) having a cathode inlet (92), and with a housing (50) in which the at least one fuel cell (90) is arranged, the housing (50) having at least one ventilation inlet (52) through which at least one ventilation fluid flows in and at least one outflow outlet (54) through which at least one outflow fluid flows out. The fuel cell system (100) further comprises a supply line (14) to the at least one cathode inlet (92) for providing a supply fluid from a first fluid source to the at least one cathode inlet (14), and a compressor (16) in the supply line (14) for compressing the supply fluid.

Abstract: A method for starting a fuel cell system comprising: determining a first pressure difference between a first pressure, which is present in an anode chamber of the fuel cell system, the anode chamber being connected to an anode of at least one fuel cell, and an ambient pressure; determining a second pressure difference between a second pressure, which is present in a cathode chamber of the fuel cell system, the cathode chamber being connected to a cathode of the at least one fuel cell, and the ambient pressure; comparing the first pressure difference to a first threshold value; comparing the second pressure difference to a second threshold value; performing a pressure equalization between the anode chamber and the cathode chamber if the first pressure difference exceeds the ambient pressure by more than the first threshold value and/or if the second pressure difference exceeds the ambient pressure by more than the second threshold value; and feeding fuel into the anode chamber.

Abstract: The invention relates to a fuel cell system (100) having at least one fuel cell stack (101), an air path (10), wherein air from the surroundings reach the fuel cell stack (101) via the air path (10), an exhaust gas path (12), a fuel line (20), wherein fuel is transported to the fuel cell stack (101) via the fuel line (20). According to the invention, the air path (10) is connected to a cooling line (30) via a branch (33), wherein the cooling line (30) is connected to a PDU unit (32).

Abstract: The present invention relates to a determination method (200) for determining a crossover rate (CR) of at least one fuel cell (10) of a fuel cell system (100) for regulation of the fuel cell system (100), the determination method (200) having the following method steps: detecting (202) fill levels (F) of water (W) in a moisture separator (20) of the fuel cell system (100) by means of a fill level detection device (24), draining (204) water (W) out of the moisture separator (20) using a drainage device (22) of the moisture separator (20), measuring (206) a first time (t1) during drainage (204) between a first fill level (F1) and at least a second fill level (F2) of the water (W) in the moisture separator (20), determining (208) the crossover rate (CR) of the at least one fuel cell (10) from the measured first time (t1) and the at least two measured fill levels (F1, F2) by means of a computer unit (30) of the fuel cell system (100), wherein the crossover rate (CR) corresponds to a transition rate of water (W

Abstract: A method for operating a fuel cell system comprises: feeding an oxidation gas stream to a cathode inlet of a cathode of a fuel cell of the fuel cell system; feeding a cathode exhaust gas stream from a cathode outlet of the cathode to an exhaust gas inlet of the humidifier; discharging the cathode exhaust gas stream from the humidifier via an exhaust gas outlet of the humidifier; humidifying the oxidation gas stream in the humidifier by means of the water extracted from the cathode exhaust gas stream; determining at least one of the following indicators for the moisture content of the cathode exhaust gas: a pressure drop between the cathode inlet and the cathode outlet, a pressure drop between the exhaust gas inlet and the exhaust gas outlet of the humidifier, a first temperature difference of the cathode exhaust gas stream between the exhaust gas inlet and the exhaust gas outlet of the humidifier, a second temperature difference of the oxidation gas stream between the oxidation gas inlet and the oxidation gas

Abstract: The invention relates to a fuel cell system comprising: a fuel cell arrangement having at least one fuel cell and an air inlet, a feed line connected to the air inlet, a central air filter device which is connected to an inlet of the feed line either directly or via a distributor block, and a compressor which is located in the feed line and which is designed to suck in ambient air through the central air filter device and to convey said air through the feed line to the air inlet of the fuel cell arrangement. The invention also relates to a decentralized air filter system, which is designed to filter, downstream of the central filter device, air conveyed from the compressor to the air inlet. The decentralized air filter system comprises at least one decentralized air filter device which is located in the feed line between the compressor and the air inlet of the fuel cell arrangement, in the distributor block, or in the central air filter device.

Abstract: The invention relates to a fuel cell system (100) having at least one fuel cell stack (101), an air path (10), wherein air from the surroundings reach the fuel cell stack (101) via the air path (10), an exhaust gas path (12), a fuel line (20), wherein fuel is transported to the fuel cell stack (101) via the fuel line (20). According to the invention, the air path (10) is connected to a cooling line (30) via a branch (33), wherein the cooling line (30) is connected to a PDU unit (32).

Abstract: The invention relates to a fuel cell system (100) with at least one fuel cell (90), each fuel cell (90) having a cathode inlet (92), and with a housing (50) in which the at least one fuel cell (90) is arranged, the housing (50) having at least one ventilation inlet (52) through which at least one ventilation fluid flows in and at least one outflow outlet (54) through which at least one outflow fluid flows out. The fuel cell system (100) further comprises a supply line (14) to the at least one cathode inlet (92) for providing a supply fluid from a first fluid source to the at least one cathode inlet (14), and a compressor (16) in the supply line (14) for compressing the supply fluid.

Abstract: The invention relates to a waste heat recovery system (3) for an internal combustion engine (1), having a working fluid circuit (19) with a condenser (31) that is also connected to a working fluid cooling circuit (34), and wherein the working fluid cooling circuit (34) has a cooler (35). The invention provides a waste heat recovery system (3) having a working fluid cooling circuit (34) which is improved in comparison to one design of a working fluid cooling circuit (34). This is achieved by the working fluid cooling circuit (34) having a cooler bypass (46). This configuration makes it generally possible for part of the coolant volume flow to be routed past the cooler (35). This is advantageous in particular at low temperatures since otherwise very low pressures arise in the working fluid cooling circuit (34).

Abstract: The invention relates to a waste-heat utilization assembly (1) of an internal combustion engine (50), comprising a working circuit (2) that conducts a working fluid. The working circuit (2) is equipped with a feed pump (6), an evaporator (10), an expansion machine (3) and a condenser (4) in the direction of flow of the working fluid. Additionally, the evaporator (10) is also arranged in an exhaust tract (53) of the internal combustion engine (50). The exhaust tract (53) is equipped with an exhaust bypass channel (61) parallel to the evaporator (10), and the exhaust tract (53) is equipped with an exhaust bypass valve (60), by means of which the distribution of the mass flow rate of the exhaust of the internal combustion engine (50) to the evaporator (10) and to the exhaust bypass channel (61) can be controlled. The waste-heat utilization assembly (1) further comprises a cooling device (20, 40, 30) which conducts a coolant, and the condenser (4) is arranged in the cooling device (20, 40, 30).

Abstract: The invention relates to a waste heat recovery system (3) for an internal combustion engine (1), having a working fluid circuit (19) with a condenser (31) that is also connected to a working fluid cooling circuit (34), and wherein the working fluid cooling circuit (34) has a cooler (35). The invention provides a waste heat recovery system (3) having a working fluid cooling circuit (34) which is improved in comparison to one design of a working fluid cooling circuit (34). This is achieved by the working fluid cooling circuit (34) having a cooler bypass (46). This configuration makes it generally possible for part of the coolant volume flow to be routed past the cooler (35). This is advantageous in particular at low temperatures since otherwise very low pressures arise in the working fluid cooling circuit (34).

Abstract: The invention relates to a waste-heat utilization assembly (1) of an internal combustion engine (50), comprising a working circuit (2) that conducts a working fluid. The working circuit (2) is equipped with a feed pump (6), an evaporator (10), an expansion machine (3) and a condenser (4) in the direction of flow of the working fluid. Additionally, the evaporator (10) is also arranged in an exhaust tract (53) of the internal combustion engine (50). The exhaust tract (53) is equipped with an exhaust bypass channel (61) parallel to the evaporator (10), and the exhaust tract (53) is equipped with an exhaust bypass valve (60), by means of which the distribution of the mass flow rate of the exhaust of the internal combustion engine (50) to the evaporator (10) and to the exhaust bypass channel (61) can be controlled. The waste-heat utilization assembly (1) further comprises a cooling device (20, 40, 30) which conducts a coolant, and the condenser (4) is arranged in the cooling device (20, 40, 30).

Abstract: A method for operating a line circuit (4) for waste heat utilization of an internal combustion engine (2), and a control unit (1). A feed pump (6), at least one heat exchanger (8), an expansion machine (10), a condenser (12) and a control unit (1) are situated in the line circuit (4). The control unit (1) calculates a time period which is required until individual components or all the components of the line circuit (4) have reached a predefined temperature, in order to start up the line circuit (4) at least partially.

Abstract: The invention relates to a method for operating a steam cycle process for using the heat of an internal combustion engine (2), comprising a conduction circuit (4) in which a working medium circulates. Said conduction circuit (4) comprises at least one pump (6, 13), at least one heat exchanger (8), an expansion machine (10), a feedwater tank (14) for storing the liquid working medium, and a condenser (12). Components of the conduction circuit (4) are frost-proofed by partially evacuating the liquid working medium. After the end of the circulation of the working medium, at least one of the pumps (6, 13) continues to operate in order to evacuate the working medium at least from the pump (6, 13) which continues to operate.

Abstract: The invention relates to a device and a method for the recovery of waste heat from an internal combustion engine (2), according to which a feed pump (6), a heat exchanger (8), an expansion engine (10) and a capacitor (12) are arranged in a circuit (4) containing a circulating working medium. A bypass connection (14) is mounted in parallel to the expansion engine (10), in the circuit (4), the expansion engine (10) being coupled to the circuit (4), or decoupled therefrom, according to an operating situation of the internal combustion engine (2).

Abstract: The invention relates to a method and a device for using the waste heat of an internal combustion engine (2) comprising a thermodynamic working circuit (4) in which a working medium circulates. A pump (6), at least one heat exchanger (8) at least one expansion machine (10) and at least one capacitor (12) are arranged in the direction of flow of the working medium. The mechanical energy generated by the expansion machine (10) is selectively transferred to a drive train (23) and/or at least one other component (25) which can be driven mechanically.

Abstract: A line circuit (4) and a method for operating a line circuit (4) for waste-heat utilization of an internal combustion engine (2) are proposed. A working medium circulates in the line circuit (4). The line circuit (4) contains a feed pump (6), at least one heat exchanger (8), an expansion machine (10), a feed-water container (14), in order to store the liquid working medium, and a condenser (12), wherein the feed-water container (14) is connected to the feed pump (6) by way of a line (29). The feed pump (6) has a return-flow line (30), via which liquid working medium can be discharged from the feed pump (6).

Abstract: The invention relates to a method for operating a steam cycle process for using the heat of an internal combustion engine (2), comprising a conduction circuit (4) in which a working medium circulates. Said conduction circuit (4) comprises at least one pump (6, 13), at least one heat exchanger (8), an expansion machine (10), a feedwater tank (14) for storing the liquid working medium, and a condenser (12). Components of the conduction circuit (4) are frost-proofed by partially evacuating the liquid working medium. After the end of the circulation of the working medium, at least one of the pumps (6, 13) continues to operate in order to evacuate the working medium at least from the pump (6, 13) which continues to operate.

Abstract: The invention relates to a device and a method for the recovery of waste heat from an internal combustion engine (2), according to which a feed pump (6), a heat exchanger (8), an expansion engine (10) and a capacitor (12) are arranged in a circuit (4) containing a circulating working medium. A bypass connection (14) is mounted in parallel to the expansion engine (10), in the circuit (4), the expansion engine (10) being coupled to the circuit (4), or decoupled therefrom, according to an operating situation of the internal combustion engine (2).