Method, control device, and computer program for determining the nitrogen concentration in the gas mixture in an anode line system of a fuel cell system, and nitrogen concentration determining device, fuel cell system, vehicle, and computer-readable medium

Abstract

The invention relates to a method, a control device (160), and a computer program for determining the nitrogen concentration in the gas mixture in an anode conducting system (130) of a fuel cell system (100) and to a nitrogen concentration determining device (150), to a fuel cell system (100), to a vehicle, and to a compuer-readable medium. The method according to the invention has the steps of receiving a first pressure signal which is representative of the pressure of the fuel received by a jet pump (139); receiving a second pressure signal which is representative of the pressure of the gas mixture in the anode line system (130) downstream of the fuel cell (110); receiving a first temperature signal which is representative of the temperature of the gas mixture in the anode line system (130) downstream of the fuel cell (110); receiving a second temperature signal which is representative of the temperature of the gas mixture in the anode line system (130) upstream of the fuel cell (110); determining the nitrogen concentration in the anode line system (130) of the fuel cell system (100) on the basis of the received signals; and transmitting a nitrogen signal which is representative of the determined nitrogen concentration.

Description

[0001] 202401281

[0002] 1

[0003] Description

[0004] Method, control device and computer program for determining a nitrogen concentration in the gas mixture in an anode piping system of a fuel cell system, as well as nitrogen concentration determination device, fuel cell system, vehicle and computer-readable medium

[0005] The present invention relates to a method, a control device and a computer program for determining a nitrogen concentration in the gas mixture in an anode piping system of a fuel cell system at a position downstream of the fuel cell, as well as a nitrogen concentration determination device, a fuel cell system, a vehicle and a computer-readable medium.

[0006] Fuel cell systems are typically operated with a fuel, such as hydrogen, which is supplied to the anode of the fuel cell. To ensure that sufficient fuel is available throughout the fuel cell, it is known to supply the anode with more fuel than is necessary to generate the current electrical output. The ratio of the mass flow rate of fuel supplied from the tank to the anode piping system to the mass flow rate of fuel oxidized at the anode can be called the anode lambda value and can therefore be a measure of the fuel surplus. The excess fuel exits at the anode outlet and is returned to the anode inlet via recirculation.

[0007] It was observed that nitrogen and water also accumulate in the anode piping system over time, so that a mixture of the three components—fuel, nitrogen, and water—can be present at the anode outlet. If the water content increases, some of the water can condense and be collected in a water separator. The separated water is then drained from the system. Furthermore, nitrogen can accumulate in the anode piping circuit.

[0008] 2. This can lead to a reduction in the fuel mass flow rate in the anode piping system and thus to a lower fuel surplus, which can also cause the anode lambda value to decrease. If the fuel surplus falls below a predetermined threshold, a (local) fuel undersupply can occur in the fuel cell, potentially leading to damage. For this reason, the anode piping system is regularly purged to remove at least some of the nitrogen. A threshold of approximately 30% nitrogen in the anode piping system is just about acceptable, as higher nitrogen concentrations not only pose a risk of fuel cell damage, such as premature aging, but also significantly reduce the fuel cell's efficiency.

[0009] During a purging process of the anode piping system, not only nitrogen but also at least some hydrogen is removed. Since there is currently no way to directly measure the nitrogen concentration in the anode piping system, for example using a suitable sensor, these purging processes are carried out periodically and / or depending on the load.

[0010] Exemplary methods and devices are known from US 2009 / 0 104 502 A1, CN 116 487 653 A, US 2008 / 0 008 921 A1, CN 109 698 366 A and WO 2023 / 138 977 A.

[0011] The present invention is essentially based on the objective of providing a method and a control device with which the nitrogen concentration of the gas mixture in the anode piping system of a fuel cell system can be determined in a simple and reliable manner, thereby enabling effective control of the purging processes of the anode piping system.

[0012] This task is accomplished by a method according to claim 1, a control device according to claim 8, a nitrogen concentration measuring device according to claim 10, a 202401281

[0013] 3

[0014] The fuel cell system according to claim 12, a vehicle according to claim 13, a computer program according to claim 14, and a computer-readable medium according to claim 15 are solved. Advantageous embodiments are specified in the dependent claims.

[0015] The present invention is essentially based on the idea of ​​recording predetermined and measurable parameters of the gas mixture and fuel upstream and downstream of a jet pump in the anode piping system of a fuel cell and, based on this, determining the nitrogen concentration in the gas mixture at a position downstream of the fuel cell. For example, based on the predetermined and measurable parameters, such as pressure, temperature, and fuel content, a mathematical model, such as a regression model, can be created from which the nitrogen concentration can be determined.

[0016] Consequently, according to a first aspect of the present invention, a method for determining a nitrogen concentration in the gas mixture in an anode piping system of a fuel cell system at a position downstream of the fuel cell is disclosed. The fuel cell system comprises a tank in which a fuel is stored and the anode piping system, which is configured to supply the fuel flowing from the tank to an anode of the fuel cell and to discharge or return the gas mixture flowing past the anode. The anode piping system comprises a jet pump, which is configured to be driven by the fuel from the tank and to circulate the gas mixture in the anode piping system.The method according to the invention comprises receiving a first pressure signal that is representative of the pressure of the fuel taken in by the jet pump, receiving a second pressure signal that is representative of the pressure of the gas mixture in the anode piping system downstream of the fuel cell and upstream of the jet pump, receiving a first temperature signal that is representative of the temperature of the gas mixture in the anode piping system downstream of the fuel cell and upstream of the jet pump, receiving a second 202401281.

[0017] 4

[0018] The invention comprises: a temperature signal representative of the temperature of the gas mixture in the anode conduction system upstream of the fuel cell and downstream of the jet pump; a determination of the nitrogen concentration in the anode conduction system of the fuel cell system at a position downstream of the fuel cell based on the received first pressure signal, the received second pressure signal, the received first temperature signal, and the received second temperature signal; and the transmission of a nitrogen signal representative of the determined nitrogen concentration. According to the invention, the nitrogen concentration can thus be determined from the four received signals.

[0019] Preferably, the method according to the invention further comprises receiving a third pressure signal, which is representative of the pressure of the gas mixture in the anode piping system upstream of the fuel cell and downstream of the jet pump. The determination of the nitrogen concentration in the anode piping system of the fuel cell system at the position downstream of the fuel cell is further based on the received third pressure signal.

[0020] The third pressure signal can be generated by a pressure sensor. Alternatively, the third pressure signal can be generated based on the received first and second pressure signals, as well as by considering the geometry of the jet pump.

[0021] By using a further, fifth parameter, such as the third pressure signal, the accuracy of determining the nitrogen concentration can be at least partially increased.

[0022] In a preferred embodiment, the method according to the invention further comprises receiving a first fuel signal that is representative of the fuel concentration in the gas mixture in the anode conduction system downstream of the fuel cell and upstream of the jet pump. The determination of the nitrogen concentration in the anode conduction system of the 202401281 is based on

[0023] 5

[0024] Fuel cell system at the position downstream of the fuel cell, furthermore on the received first fuel signal.

[0025] In a further preferred embodiment, the method according to the invention further comprises receiving a second fuel signal, which is representative of the fuel concentration in the gas mixture in the anode conduction system upstream of the fuel cell and downstream of the jet pump. The determination of the nitrogen concentration in the anode conduction system of the fuel cell system at the position downstream of the fuel cell is further based on the received second fuel signal.

[0026] Preferably, the nitrogen concentration in the anode conduction system of the fuel cell system is determined downstream of the fuel cell using a mathematical model, more preferably a regression model. It can be advantageous if the mathematical model is trained using an artificial neural network.

[0027] According to a further aspect of the present invention, a control device is disclosed which is configured to perform the steps of the method for determining a nitrogen concentration in the gas mixture in an anode conduction system of a fuel cell system at a position downstream of the fuel cell.

[0028] In a preferred embodiment, the control device according to the invention comprises a first control device section for performing the step of receiving the first pressure signal, a second control device section for performing the step of receiving the second pressure signal, a third control device section for performing the step of receiving the first temperature signal, a fourth control device section for performing the step of receiving the second temperature signal, and a fifth control device section for performing the step of determining the 202401281

[0029] 6

[0030] Nitrogen concentration in the gas mixture in the anode piping system of the fuel cell system at a position downstream of the fuel cell and a sixth control device section for performing the step of sending the nitrogen signal.

[0031] According to a further aspect of the present invention, a nitrogen concentration detection device for determining the nitrogen concentration in the gas mixture in an anode piping system of a fuel cell system at a position downstream of the fuel cell is disclosed. The nitrogen concentration detection device according to the invention comprises a first pressure sensor configured to generate a first pressure signal representative of the pressure of the fuel taken up by the jet pump, a second pressure sensor configured to generate a second pressure signal representative of the pressure of the gas mixture in the anode piping system upstream of the jet pump and downstream of the fuel cell, and a first temperature sensor configured to generate a first temperature signal.which is representative of the temperature of the gas mixture in the anode piping system upstream of the jet pump and downstream of the fuel cell, a second temperature sensor configured to generate a second temperature signal that is representative of the temperature of the gas mixture in the anode piping system downstream of the jet pump and upstream of the fuel cell, and a control device according to the invention.

[0032] In an advantageous embodiment, the nitrogen concentration determination device according to the invention further comprises a third pressure sensor which is configured to generate a third pressure signal that is representative of the pressure of the gas mixture in the anode piping system downstream of the jet pump and upstream of the fuel cell.

[0033] According to a further aspect of the present invention, a fuel cell system is disclosed which comprises a fuel cell with an anode and a cathode, a tank in which a fuel is stored, a 202401281

[0034] 7

[0035] An anode piping system designed to supply the fuel flowing from the tank to the anode of the fuel cell of the fuel cell system and to drain or return the gas mixture flowing past the anode, and comprising a nitrogen concentration measuring device according to the invention.

[0036] According to a further aspect of the present invention, a vehicle with a fuel cell system according to the invention is disclosed.

[0037] According to a further aspect of the present invention, a computer program is disclosed which includes instructions which, when executed by a computing unit, cause the computing unit to execute a method according to the invention for determining a nitrogen concentration in the gas mixture in an anode piping system of a fuel cell system.

[0038] According to a further aspect of the present invention, a computer-readable medium is disclosed on which the computer program according to claim 14 is stored.

[0039] Further advantages and features of the present invention will become apparent to the person skilled in the art by carrying out the teaching described herein and by examining the single accompanying drawing, in which:

[0040] Fig. 1 shows a schematic representation of a fuel cell system according to the invention for a vehicle, and

[0041] Fig. 2 shows an exemplary flowchart of a method according to the invention for determining a nitrogen concentration in the gas mixture in an anode piping system of the fuel cell system of Fig. 1.

[0042] Within the scope of the present disclosure, the term "jet pump" describes a gas mixture transfer pump in which the pumping action is carried out by a fluid jet 202401281

[0043] 8

[0044] (propellant medium) is generated, which, through momentum exchange, draws in, accelerates and compresses / conveys another medium (suction medium), provided it is under sufficient pressure.

[0045] Within the context of this disclosure, the term "regression model" describes a set of statistical analysis methods designed to model relationships between a dependent variable and one or more independent variables. A linear or polynomial regression model can be used.

[0046] Within the context of this disclosure, the term "gas mixture" describes a mixture of various gaseous components, such as fuel, e.g. hydrogen, nitrogen and water or water vapor.

[0047] Within the scope of this disclosure, the term "signal" describes raw data that is converted into a form suitable for transmission via the chosen transport medium. This can be done analogously or digitally, whereby the data is first sampled and converted into discrete (often binary-coded) values, which are then transmitted as current pulses or voltages of varying amplitudes via the medium. Furthermore, within the scope of this disclosure, the signals can be transmitted and received continuously. For example, the transmission and reception of digital signals occur at intervals of a few milliseconds.

[0048] Fig. 1 shows a schematic representation of a fuel cell system 100 according to the invention for a vehicle. The fuel cell system 100 comprises a fuel cell 110, such as a fuel cell stack. As is known from the prior art, the fuel cell 110 comprises an anode and a cathode separated from each other by a membrane. For example, the fuel cell 110 can be a so-called PEM fuel cell, in which the membrane is a proton exchange membrane through which the protons formed at the anode can pass to the cathode. 202401281

[0049] 9

[0050] The fuel cell system 100 further comprises a tank 120 in which a fuel, such as hydrogen, is stored, preferably under pressure. Alternatively, the fuel can be ammonia.

[0051] The fuel cell system 100 of Fig. 1 further comprises an anode line system 130, which is configured to supply the fuel flowing from the tank 120 to the anode of the fuel cell 110 and to discharge or return the gas mixture flowing past the anode. For this purpose, the anode line system 130 comprises an anode supply line 132, which is fluidly connected to the tank 120 and supplies the fuel flowing from the tank 120 and the gas mixture present upstream of the anode to an anode line 134, which in turn supplies the gas mixture to the anode of the fuel cell 110. The anode line system 130 further comprises an anode return line 136, which is fluidly connected to the anode line 134 and can discharge the gas mixture flowing through the anode line 134 and feed it into an exhaust system.The anode line system 130 further comprises an anode return line 138, which fluidly connects the anode outlet 136 to the anode supply line 132 and in which a jet pump 139 is arranged. The jet pump is designed to return the gas mixture flowing through the anode outlet 136 back to the anode supply line 132. Consequently, a circuit is formed between the anode supply line 132, the anode line 134, the anode outlet 136, and the anode return line 138, in which the fuel-containing gas mixture can be circulated by means of the return pump 139. The jet pump 139 is specifically designed to be driven by the fuel supplied from the tank 120 and to draw the gas mixture from the anode outlet 136. The fuel originating from tank 120 is thus the motive medium and the recirculated gas mixture from the anode line 136 is the suction medium for the jet pump 139.

[0052] The anode line system 130 further comprises a flushing valve 137, which is located in the anode line 136 downstream of the outlet of the anode return line 202401281

[0053] 10

[0054] The purge valve 138 is arranged and configured to open or close the anode drain 136. In a normal operating mode of the fuel cell 110, the purge valve 137 is closed, so that the recirculation and circulation process of the gas mixture described above can be provided by means of the recirculation pump 139. The purge valve 137 can be configured as a throttle valve or a solenoid valve.

[0055] The fuel cell system 100 further comprises a first pressure sensor 142, which, according to the embodiment shown in Fig. 1, is arranged in the anode supply line 132 and is configured to generate a first pressure signal that is representative of the pressure of the fuel drawn from the tank 120 by the jet pump 139. Alternatively, the first pressure sensor 142 can be arranged directly at the outlet of the tank 120 or inside the tank 120.

[0056] The fuel cell system 100 further comprises a second pressure sensor 144, which, according to the embodiment of Fig. 1, is arranged in the anode return line 138 upstream of the jet pump 139 and is designed to generate a second pressure signal that is representative of the pressure of the gas mixture in the anode line system 130 downstream of the fuel cell 110 and upstream of the jet pump 139.

[0057] The fuel cell system 100 further comprises a third pressure sensor 146, which, according to the embodiment of Fig. 1, is arranged in the anode supply line 132 downstream of the jet pump 139 and upstream of the fuel cell 110 and is designed to generate a third pressure signal that is representative of the pressure of the gas mixture in the anode supply line system 130 downstream of the jet pump 139 and upstream of the fuel cell 110.

[0058] The fuel cell system 100 further comprises a first temperature sensor 143, which, according to the embodiment of Fig. 1, is arranged in the anode line 136 upstream of the jet pump 139 and downstream of the fuel cell 110 and is designed to generate a first temperature signal that is representative of the temperature of the gas mixture in the anode line system 202401281

[0059] 11

[0060] 130 upstream of the jet pump 139 and downstream of the fuel cell 110. Alternatively, the first temperature sensor 143 can be located in the anode return line 138.

[0061] The fuel cell system 100 further comprises a second temperature sensor 145, which, according to the embodiment of Fig. 1, is arranged in the anode supply line 132 downstream of the jet pump 139 and upstream of the fuel cell 110 and is designed to generate a second temperature signal that is representative of the temperature of the gas mixture in the anode supply line system 130 downstream of the jet pump 139 and upstream of the fuel cell 110.

[0062] The fuel cell system 100 can additionally include an optional third temperature sensor 147, which can be arranged in the anode supply line 132 upstream of the jet pump 139 and configured to generate a third temperature signal representative of the temperature of the fuel drawn from the tank 120 by the jet pump 139. Alternatively, the third temperature sensor 147 can be arranged directly at the outlet of the tank 120 or inside the tank 120.

[0063] Furthermore, a first fuel sensor 131, such as a hydrogen sensor, is provided in the anode supply line 132. This sensor is configured to generate a first fuel signal that is representative of the fuel content or fuel concentration in the gas mixture in the anode supply line 132 downstream of the jet pump 139 and upstream of the anode of the fuel cell 110. The first fuel sensor 131 can be a fuel sensor based on the thermal conductivity principle. The first fuel signal of the first fuel sensor 131 is preferably a digital signal or data that can be processed by a data processing device, which may include a processor and a memory. The first fuel sensor 131 is configured to transmit several (digital) first fuel signals continuously, for example, at predetermined intervals, such as a few milliseconds. 202401281

[0064] 12

[0065] Furthermore, a second fuel sensor 133, such as a hydrogen sensor, is provided in the anode line 136. This sensor is configured to generate a second fuel signal that is representative of the fuel content or fuel concentration in the gas mixture in the anode line 136 downstream of the anode of the fuel cell 110 and upstream of the jet pump 139. The second fuel sensor 133 can be a fuel sensor based on the thermal conductivity principle. The second fuel signal from the second fuel sensor 133 is preferably a digital signal or data that can be processed by a data processing device, which may include a processor and memory. The second fuel sensor 133 is configured to transmit several (digital) second fuel signals continuously, for example, at predetermined intervals, such as a few milliseconds.

[0066] Furthermore, it is possible to provide a mass flow meter (not shown) which, for example, is arranged in the anode supply line 132 and is configured to generate a mass flow signal that is representative of the mass flow of the fuel supplied from the tank 120 to the anode supply system 130. For this purpose, the mass flow meter can include a pressure sensor, such as the first pressure sensor 142, a temperature sensor, such as the third temperature sensor 147, and a supply valve configured to control the opening cross-section of a fluid connection between the tank 120 and the anode supply system 130, in particular the anode supply line 132.For example, the feed valve is an electrically actuated control valve, such as a butterfly valve or a needle valve, designed to adjust the opening cross-section of the fluid connection between the tank 120 and the anode piping system 130 according to a received valve control signal. Based on the first pressure signal, the third temperature signal, and the opening cross-section of the feed valve, the mass flow signal can then be generated. Alternatively or additionally to the feed valve, the opening cross-section of the jet pump 139 can be taken into account.

[0067] 13 will be used to determine the mass flow rate of the fuel supplied from tank 120 into the anode piping system 130.

[0068] The fuel cell system 100 also includes a cathode conduction system (not shown), which will not be discussed in detail here. The cathode conduction system is specifically designed to supply oxygen to the cathode of the fuel cell.

[0069] The fuel cell system 100 of Fig. 1 further comprises a vehicle electrical system branch 102, which includes electrical loads. In particular, the vehicle electrical system branch 102 describes at least a part of an electrical system that can store and distribute the electrical energy, especially electrical current, supplied by the fuel cell 110. A current sensor 104 is provided for detecting and monitoring the electrical current supplied by the fuel cell 110. The current sensor 104 is configured to generate a current signal that is representative of the electrical current supplied by the fuel cell 110. The current sensor 104 is configured to send several (digital) current signals continuously, for example, at predetermined intervals, such as a few milliseconds.

[0070] The first pressure sensor 142, the second pressure sensor 144, the third pressure sensor 146, the first temperature sensor 143, the second temperature sensor 145, the third temperature sensor, the first fuel sensor 131, the second fuel sensor 133 and a control device 160 can form a nitrogen concentration detection device 150 (see dashed line in Fig. 1).

[0071] The control device 160 can be connected to all components of the fuel cell system 100. Although no separate lines are shown in Fig. 1, such electrical connections can be in the form of connecting cables or wires, or wireless communication devices. The control device 160 can have several control device sections 202401281

[0072] 14 have, for example, a first control device section 161, a second control device section 162, a third control device section 163, a fourth control device section 164, a fifth control device section 165 and a sixth control device section 166, which are discussed in more detail below with reference to Fig. 2.

[0073] The control device 160 can include a processor or arithmetic unit and memory. Alternatively, the control device 160 can be the processor or arithmetic unit connected to the memory. The processor can be a central processing unit (CPU). The processor can also be another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or another programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or the like. The general-purpose processor can be a microprocessor, or the processor can be any conventional processor or the like.

[0074] The memory includes, but is not limited to, Random Access Memory (RAM), Read-Only Memory (ROM), Erasable Programmable Read-Only Memory (EPROM), or Portable Read-Only Memory (e.g., CD-ROM). The memory is configured to store associated program instructions and related data.

[0075] The following describes, with additional reference to the flowchart shown in Fig. 2, an exemplary embodiment of a method according to the invention for determining a nitrogen concentration in the gas mixture in the anode piping system 130 of the fuel cell system 100 of Fig. 1 at a position downstream of the fuel cell 110, in particular downstream of the anode. 202401281

[0076] 15

[0077] The process of Fig. 2 starts at step 200 and then proceeds to step 210, in which the control device 160, in particular the first control device section 161, receives a first pressure signal from the first pressure sensor 142. In a subsequent step 220, which can also occur simultaneously with step 210, the control device 160, in particular the second control device section 162, receives a second pressure signal from the second pressure sensor 144. In a subsequent step 230, which can also occur simultaneously with step 210 and / or step 220, the control device 160, in particular the third control device section 163, receives a first temperature signal from the first temperature sensor 143.In a further step 240, which can also be carried out simultaneously with step 210 and / or step 220 and / or step 230, the control device 160, in particular the fourth control device section 163, receives a second temperature signal from the second temperature sensor 145.

[0078] In a subsequent step 250, the control device 160, in particular the fifth control device section 165, determines the nitrogen concentration in the gas mixture in the anode conduction system 130 of the fuel cell system 100 at the position downstream of the fuel cell 110, based on the first pressure signal received in step 210, the second pressure signal received in step 220, the first temperature signal received in step 230, and the second temperature signal received in step 240. This can preferably be done using a predetermined mathematical model, such as a regression model. Various nitrogen concentrations for different gas mixture parameters (such as pressures, temperatures, fuel concentrations, etc.) can be empirically determined beforehand, from which the mathematical model, in particular the regression model, can then be predetermined.

[0079] 16

[0080] To increase the accuracy in determining the nitrogen concentration, it may be preferred to additionally receive a third pressure signal from the third pressure sensor 146 and / or a third temperature signal from the third temperature sensor 147 and to take these into account when determining the nitrogen concentration. It is also preferred to receive a first fuel signal from the first fuel sensor 131 and / or a second fuel signal from the second fuel sensor 133 and to take these into account when determining the nitrogen concentration. It should be noted that the accuracy of determining the nitrogen concentration according to the invention increases with the number of gas mixture parameters that are recorded and considered in the mathematical model. Furthermore, it has been found that considering the first and / or second fuel signal significantly increases the accuracy.

[0081] In a subsequent step, a nitrogen signal is sent by means of the control device 160, in particular by means of the sixth control device section 166, before the method ends at step 270.

[0082] According to the invention, various gas mixture parameters, such as pressure, temperature and fuel concentration, can thus be recorded or determined at different positions in the anode conduction system 130, on the basis of which the nitrogen concentration can then be determined.

Claims

202401281 17 Patent claims 1. A method for determining a nitrogen concentration in the gas mixture in an anode piping system (130) of a fuel cell system (100) at a position downstream of the fuel cell (110), wherein the fuel cell system (100) comprises a tank (120) in which a fuel is stored, and the anode piping system (130) configured to supply the fuel flowing out of the tank (120) to an anode of the fuel cell (110) and to discharge or return the gas mixture flowing past the anode, wherein the anode piping system (130) comprises a jet pump (139) configured to be driven by the fuel from the tank (120) and to circulate the gas mixture in the anode piping system (130), wherein the method comprises: Receiving an initial pressure signal that is representative of the pressure of the fuel taken in by the jet pump (139), Receiving a second pressure signal that is representative of the pressure of the gas mixture in the anode piping system (130) downstream of the fuel cell (110) and upstream of the jet pump (139), Receiving a first temperature signal that is representative of the temperature of the gas mixture in the anode piping system (130) downstream of the fuel cell (110) and upstream of the jet pump (139), Receiving a second temperature signal that is representative of the temperature of the gas mixture in the anode conduction system (130) upstream of the fuel cell (110) and downstream of the jet pump (139), Determining the nitrogen concentration in the anode conduction system (130) of the fuel cell system (100) at a position downstream of the fuel cell (110) based on the received first pressure signal, the received second pressure signal, the received first temperature signal and the received second temperature signal, and 202401281 18 Sending a nitrogen signal that is representative of the determined nitrogen concentration.

2. Method according to claim 1, further comprising: Receiving a third pressure signal that is representative of the pressure of the gas mixture in the anode piping system (130) upstream of the fuel cell (110) and downstream of the jet pump (139), wherein determining the nitrogen concentration in the anode piping system (130) of the fuel cell system (100) at the position downstream of the fuel cell (110) is further based on the received third pressure signal.

3. Method according to any of the preceding claims, further comprising: Receiving a first fuel signal that is representative of the fuel concentration in the gas mixture in the anode conduction system (130) downstream of the fuel cell (110) and upstream of the jet pump (139), wherein determining the nitrogen concentration in the anode conduction system (130) of the fuel cell system (100) at the position downstream of the fuel cell (110) is further based on the received first fuel signal.

4. Method according to any of the preceding claims, further comprising: Receiving a second fuel signal that is representative of the fuel concentration in the gas mixture in the anode conduction system (130) upstream of the fuel cell (110) and downstream of the jet pump (139), wherein determining the nitrogen concentration in the anode conduction system (130) of the fuel cell system (100) at the position downstream of the fuel cell (110) is further based on the received second fuel signal. 202401281 19 5. Method according to one of the preceding claims, wherein the determination of the nitrogen concentration in the anode conduction system (130) of the fuel cell system (100) at the position downstream of the fuel cell (110) is carried out using a mathematical model.

6. The method of claim 5, wherein the mathematical model is a regression model.

7. Method according to one of claims 5 and 6, wherein the mathematical model is trained using an artificial neural network.

8. Control device (160) configured to perform the steps of the method according to any of the preceding claims.

9. Control device (160) according to claim 8, comprising: a first control device section (161) for performing the step of receiving the first pressure signal, a second control device section (162) for performing the step of receiving the second pressure signal, a third control device section (163) for performing the step of receiving the first temperature signal, a fourth control device section (164) for performing the step of receiving the second temperature signal, a fifth control device section (165) for performing the step of determining the nitrogen concentration in the gas mixture in the anode piping system (130) of the fuel cell system (100) at a position downstream of the fuel cell (110), and a sixth control device section (166) for performing the step of sending the nitrogen signal.

10. Nitrogen concentration measuring device (150) for determining a nitrogen concentration in the gas mixture in an anode conduction system (130) 202401281 20 of a fuel cell system (100) at a position downstream of the fuel cell (110), comprising: a first pressure sensor (142) configured to generate a first pressure signal representative of the pressure of the fuel taken up by the jet pump (139), a second pressure sensor (144) configured to generate a second pressure signal representative of the pressure of the gas mixture in the anode piping system (130) upstream of the jet pump (139) and downstream of the fuel cell (110), a first temperature sensor (143) configured to generate a first temperature signal representative of the temperature of the gas mixture in the anode piping system (130) upstream of the jet pump (139) and downstream of the fuel cell (110), a second temperature sensor (145) configured to generate a second temperature signal,which is representative of the temperature of the gas mixture in the anode piping system (130) downstream of the jet pump (139) and upstream of the fuel cell (110), and a control device (160) according to one of claims 8 and 9.

11. Nitrogen concentration detection device (150) according to claim 10, further comprising: a third pressure sensor (146) configured to generate a third pressure signal representative of the pressure of the gas mixture in the anode piping system (130) downstream of the jet pump (139) and upstream of the fuel cell (110).

12. Fuel cell system (100), comprising: a fuel cell (110) with an anode and a cathode, a tank (120) in which a fuel is stored, an anode piping system (130) configured to supply the fuel flowing out of the tank (120) to the anode of the fuel cell (110) of the fuel cell system (100) and to discharge or return the gas mixture flowing past the anode, and 202401281 21 of a nitrogen concentration measuring device (150) according to claim 11.

13. Vehicle with a fuel cell system (100) according to claim 12.

14. Computer program comprising instructions which, when executed by a computing unit, cause the computing unit to execute a method according to any one of claims 1 to 7.

15. Computer-readable medium on which the computer program according to claim 1 is stored. 14 is stored.

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