Fuel cell system and method of controlling fuel cell system

Abstract

The invention discloses a fuel cell system and a method of controlling the same, the fuel cell system including: a fuel cell stack having an anode portion adapted to receive fuel from a fuel supply unit and a cathode portion adapted to receive air from an air supply unit; an air bypass line in communication with the air supply unit; an anode fuel off-gas line adapted to discharge fuel off-gas from a fuel outlet of the anode portion; and a catalytic sensor disposed at a connection point of the air bypass line and the anode fuel off-gas line, the air bypass line being adapted to provide air to the catalytic sensor, the catalytic sensor being adapted to measure a hydrogen concentration in the fuel off-gas discharged from the fuel outlet of the anode portion. The present invention minimizes the purge loss of fuel gas and minimizes fuel consumption (by about 1% to 10% according to the difference of drive cycles). And meanwhile, it is ensured that part of fuel tail gas meets the emission standard.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a fuel cell system and a method for controlling the fuel cell system. Background Art

[0002] During the startup of the fuel cell system, when the fuel cell is running, fuel is provided to the fuel cell stack through a hydrogen bottle. The hydrogen enters the pressure reducing valve for pressure reduction, then enters the intake valve and the proportional valve, and then enters the fuel cell stack. The gas after the reaction contains a high concentration of hydrogen. This high concentration of hydrogen will be wasted if it is directly discharged from the fuel cell system through the tail exhaust. Therefore, the gas after the reaction can be re-entered into the stack through a hydrogen recycling loop.

[0003] However, it is difficult to accurately detect the hydrogen content in the fuel recirculation loop of the fuel cell system in the prior art. This is because: during the operation of the fuel cell, the air and hydrogen undergo an electrochemical reaction inside the stack to produce a large amount of water, some of which enters the fuel recirculation loop, causing the fuel recirculation loop to be in a humid environment. The hydrogen sensor has low working efficiency and slow reaction in a humid environment, making it difficult to accurately measure the hydrogen content in the fuel recirculation loop. In order to avoid damaging the stack, fast and effective purging is required, however, excessive purging may result in fuel efficiency loss or fuel emissions.

[0004] Since insufficient purging can damage the stack, and the exact hydrogen concentration in the fuel recirculation loop is unknown, the anode purge rate is often higher than required, resulting in fuel loss or high hydrogen emissions. Depending on the drive cycle and stack design, the hydrogen purge may account for 15% of the hydrogen consumed in the entire drive cycle. At the end of life (EOL), hydrogen purge is often not required or is greatly reduced, as smaller internal leaks are sufficient to maintain N2 levels in the anode circulation loop at acceptable levels. However, conventional purge control methods cannot detect this, so BOL purge levels are maintained by wasting large amounts of fuel or failing to meet emissions targets. The anode purge time is usually determined at the beginning of life (BOL) through empirical testing, and there is usually no sensor feedback to adjust the purge rate / timing based on changing conditions or aging components, nor is there feedback on failed components.

[0005] Therefore, it is necessary to provide a system and method that can accurately feedback the hydrogen concentration in the fuel recirculation loop. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the purpose of the present invention is to provide a fuel cell system and a method for controlling a fuel cell system. The present invention minimizes the purge loss of fuel gas and minimizes fuel consumption (by about 1% to 10% depending on the driving cycle). It is also beneficial to ensure that part of the fuel tail gas meets the emission standards.

[0007] In a first aspect of the present invention, the present invention provides a fuel cell system. According to an embodiment of the present invention, the fuel cell system comprises:

[0008] a fuel cell stack having an anode portion adapted to receive fuel from a fuel supply unit and a cathode portion adapted to receive air from an air supply unit;

[0009] an air bypass line, the air bypass line being in communication with the air supply unit;

[0010] an anode fuel tail gas pipeline, adapted to discharge fuel tail gas from a fuel outlet of the anode portion;

[0011] and a catalytic sensor disposed at a connection point between the air bypass line and the anode fuel tail gas line, the air bypass line being adapted to provide air to the catalytic sensor, the catalytic sensor being adapted to measure a hydrogen concentration in a fuel tail gas exhausted from a fuel outlet of the anode portion.

[0012] According to the fuel cell system of the above embodiment of the present invention, by providing part of the reacted fuel exhaust gas to the catalytic temperature sensor, and at the same time providing part of the air to the catalytic sensor, the fuel gas and air in the fuel exhaust gas react and release heat under the action of the catalytic temperature sensor, and the heat released by the reaction is conducted to the temperature sensor. The temperature change of the temperature sensor is positively correlated with the hydrogen concentration in the fuel exhaust gas, thereby obtaining the hydrogen concentration in the reacted fuel exhaust gas, and the purge speed or purge time of the fuel gas in the anode part can be adjusted according to the concentration, thereby minimizing the purge loss of the fuel gas and minimizing the fuel consumption (reduced by about 1% to 10% depending on the driving cycle). At the same time, the system can also detect and isolate faults, alarm or notify the system, or use adaptive control strategies to adjust system parameters according to the hydrogen concentration in the fuel exhaust gas.

[0013] In addition, the fuel cell system according to the above embodiment of the present invention may also have the following additional technical features:

[0014] In some embodiments of the present invention, the air bypass line is directly connected to an air outlet of a compressor of the fuel cell system.

[0015] In some embodiments of the present invention, the air bypass line is directly connected to an air outlet of an intercooler of the fuel cell system.

[0016] In some embodiments of the present invention, the catalytic sensor is a catalytic temperature sensor or a temperature sensor in thermal contact with a catalytic bearing structure.

[0017] In some embodiments of the present invention, the temperature measured by the catalytic sensor has a predefined correlation with the hydrogen concentration value in the fuel exhaust.

[0018] In some embodiments of the present invention, the fuel tail gas from the anode part is connected to the fuel inlet of the fuel cell stack through a fuel recycling loop, and the fuel recycling loop is provided with a fuel recycling device.

[0019] In some embodiments of the present invention, a flow regulating valve is provided on the air bypass line to adjust the amount of air flowing to the catalytic sensor.

[0020] In some embodiments of the present invention, the purge line of the anode portion controls a purge parameter of the fuel gas based on a hydrogen concentration signal detected from the fuel tail gas by the catalytic sensor.

[0021] In a second aspect of the present invention, the present invention provides a method for controlling the fuel cell system described in the above embodiment. According to an embodiment of the present invention, the method comprises:

[0022] Supplying part of the air provided by the air supply unit to the cathode part of the fuel cell stack, and supplying the fuel gas provided by the fuel supply unit to the anode part of the fuel cell stack, so that the air and the fuel gas undergo an electrochemical reaction in the fuel cell stack;

[0023] Providing a portion of the reacted fuel tail gas to a catalytic sensor through an anode fuel tail gas pipeline, and providing a portion of air to the catalytic sensor through an air bypass pipeline to measure the hydrogen concentration in the fuel tail gas exhausted from the anode portion;

[0024] The purge parameters of the fuel gas at the fuel inlet of the anode part are adjusted according to the hydrogen concentration in the fuel exhaust gas, or the system fault detection and isolation are performed according to the hydrogen concentration in the fuel exhaust gas, or the system is alarmed or notified according to the hydrogen concentration in the fuel exhaust gas, or the system parameters are adjusted by an adaptive control strategy according to the hydrogen concentration in the fuel exhaust gas.

[0025] According to the method for controlling the fuel gas purge of the above embodiment of the present invention, part of the reacted fuel exhaust gas is provided to the catalytic temperature sensor, and part of the air is provided to the catalytic sensor at the same time. Under the action of the catalytic temperature sensor, the fuel gas and air or oxygen in the fuel exhaust gas react and release heat, and the heat released by the reaction is conducted to the temperature sensor. The temperature change of the temperature sensor is positively correlated with the hydrogen concentration in the fuel exhaust gas, thereby obtaining the hydrogen concentration in the reacted fuel exhaust gas. The purge speed or purge time of the fuel gas in the anode part can be adjusted according to the concentration, thereby minimizing the purge loss of the fuel gas and minimizing the fuel consumption (reduced by about 1% to 10% depending on the driving cycle). At the same time, the system can also be fault-detected and isolated, the system can be alarmed or notified, or the system parameters can be adjusted using an adaptive control strategy according to the hydrogen concentration in the fuel exhaust gas.

[0026] In addition, the method according to the above embodiment of the present invention may also have the following additional technical features:

[0027] In some embodiments of the present invention, the purge parameters include flow rate control, duration control and timing control of the fuel gas.

[0028] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0030] Figure 1 is a schematic diagram of a fuel cell system according to an embodiment of the present invention.

[0031] Figure annotation:

[0032] 1- fuel supply unit, 2- anode part, 3- fuel purification unit, 4- fuel recycling device, 5- flow rate control valve, 6- air supply unit, 7- pressure sensor, 8- cathode part, 9- flow regulating valve, 10- catalytic sensor, 11- flame arrester, 12- air bypass line, 13- anode fuel tail gas line, 14- fuel recycling loop. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred elements must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0038] In one aspect of the present invention, the present invention provides a fuel cell system, referring to the attached Figure 1The fuel cell system comprises: a fuel cell stack having an anode part 2 adapted to receive fuel from a fuel supply unit 1 (e.g., a hydrogen bottle) and a cathode part 8 adapted to receive air from an air supply unit 6; an air bypass line 12, the air bypass line 12 being connected to the air supply unit; an anode fuel tail gas line 13 adapted to discharge fuel tail gas from a fuel outlet of the anode part 2; and a catalytic sensor 10, arranged at a connection point between the air bypass line 12 and the anode fuel tail gas line 13, the air bypass line 12 being adapted to provide air to the catalytic sensor 10, the catalytic sensor 10 being adapted to measure the hydrogen concentration in the fuel tail gas discharged from the fuel outlet of the anode part 2. Thus, the purge loss of the fuel gas is minimized, and the fuel consumption is minimized (reduced by about 1% to 10% depending on the driving cycle). At the same time, it is also beneficial to ensure that part of the fuel tail gas meets the emission standards. In addition, it is also beneficial to quickly detect purification system failures (purification valves, etc.).

[0039] The principle by which the fuel cell system proposed by the present invention can achieve the above beneficial effects is described in detail below:

[0040] In the prior art, during the operation of the fuel cell, air and hydrogen undergo an electrochemical reaction inside the fuel cell stack to produce a large amount of water, and part of the water enters the fuel recirculation loop, causing the fuel recirculation loop to be in a humid environment. The hydrogen sensor has a low working efficiency in a humid environment, reacts slowly, and it is difficult to accurately measure the hydrogen content in the fuel recirculation loop. In view of this, the present invention provides a system that can accurately feedback the hydrogen concentration in the fuel recirculation loop. Specifically, the present invention sets a catalytic sensor 10, and by providing the partially reacted fuel tail gas to the surface of the catalytic sensor 10, when the hydrogen content in the fuel tail gas exceeds the flammable gas limit, the catalyst surface will oxidize hydrogen and release heat, and the heat released by the reaction is conducted to the sensor, and the temperature change of the sensor is positively correlated with the concentration of hydrogen in the fuel tail gas (that is, the higher the concentration of hydrogen in the fuel tail gas, the more heat released by the reaction, and the greater the temperature change of the sensor), thereby indirectly obtaining the concentration of hydrogen in the fuel tail gas after the reaction through the temperature change of the catalytic sensor; according to the concentration of hydrogen in the fuel tail gas after the reaction of the fuel cell stack, the purge speed, purge start frequency or purge start duration of the fuel gas at the anode part fuel inlet are adjusted. This minimizes the purge loss of fuel gas and minimizes fuel consumption (by about 1% to 10% depending on the drive cycle). At the same time, the system can also detect and isolate faults, issue alarms or notifications to the system, or use adaptive control strategies to adjust system parameters based on the hydrogen concentration in the fuel exhaust.

[0041] In an embodiment of the present invention, the catalytic sensor may be a catalytic temperature sensor or a temperature sensor in thermal contact with a catalytic bearing structure. The catalytic temperature sensor is also called a catalytic exhaust temperature sensor, which measures the temperature of the exhaust gas by utilizing a catalytic element. The catalytic material on the sensor promotes a chemical reaction between the exhaust gas and the sensor surface, resulting in a change in temperature. By measuring the temperature change, the sensor can provide an indication of the exhaust gas temperature.

[0042] Temperature sensor in thermal contact with the catalytic bearing structure: In the present invention, the temperature sensor is in thermal contact with the catalytic bearing structure. The temperature sensor is designed to accurately measure the temperature of the catalytic bearing structure, and the concentration of hydrogen in the fuel exhaust after the reaction can be indirectly obtained through the temperature change of the catalytic bearing structure. Specifically, the air provided by the air bypass line 12 and the fuel exhaust provided by the anode fuel exhaust line 13 are provided to the bearing structure carrying the catalyst. When the hydrogen content in the fuel exhaust exceeds the flammable gas limit, the catalyst surface will oxidize hydrogen and release heat. The heat released by the reaction is conducted to the temperature sensor. The temperature change of the temperature sensor is positively correlated with the concentration of hydrogen in the fuel exhaust (that is, the higher the concentration of hydrogen in the fuel exhaust, the more heat released by the reaction, and the greater the temperature change of the temperature sensor). Therefore, the concentration of hydrogen in the fuel exhaust after the reaction can be indirectly obtained through the temperature change of the temperature sensor.

[0043] In the embodiments of the present invention, referring to the attached Figure 1 The air bypass line 12 is connected between the air supply unit 6 and the air inlet of the catalytic sensor 10. A portion of the air provided by the air supply unit 6 is supplied to the catalytic sensor 10 through the air bypass line 12. Under the action of the catalyst in the catalytic sensor 10, the fuel gas in the fuel exhaust reacts with the air and releases heat.

[0044] Further, see Attachment Figure 1 The air bypass line 12 is provided with a flow regulating valve 9 to adjust the amount of air flowing to the catalytic sensor 10 .

[0045] In the embodiments of the present invention, referring to the attached Figure 1 The anode fuel exhaust pipeline 13 is arranged between the fuel exhaust outlet of the anode part 2 and the air inlet of the catalytic sensor 10. The fuel exhaust gas discharged from the fuel outlet of the anode part 2 is supplied to the catalytic sensor 10 through the anode fuel exhaust pipeline 13. Under the action of the catalyst in the catalytic sensor 10, the fuel gas and air in the fuel exhaust gas react and release heat.

[0046] According to a specific embodiment of the present invention, the air bypass line is directly connected to the air outlet of the compressor of the fuel cell system.

[0047] According to yet another specific embodiment of the present invention, the air bypass line is directly connected to an air outlet of an intercooler of the fuel cell system.

[0048] According to another specific embodiment of the present invention, refer to the attached Figure 1 A fuel recycling loop 14 is provided between the fuel exhaust gas outlet and the fuel inlet of the anode part 2. The fuel exhaust gas from the anode part is connected to the fuel inlet of the fuel cell stack through the fuel recycling loop 14. The fuel recycling loop 14 is provided with a fuel recycling device 4 (such as a hydrogen circulation pump).

[0049] According to another specific embodiment of the present invention, refer to the attached Figure 1 The system also includes: a flow rate control valve 5, which is arranged on the fuel recycling loop 14 between the fuel recycling device 4 and the air inlet of the anode part 2, thereby controlling the gas flow rate in the fuel recycling loop 14, thereby controlling the hydrogen content in the mixed fuel gas after the fuel gas provided by the fuel recycling loop is mixed with the fuel gas provided by the fuel supply unit 1.

[0050] According to another specific embodiment of the present invention, refer to the attached Figure 1 The system further includes: a flame arrester 11, which is arranged within the fire extinguishing range of the catalytic sensor 10, so that the flame arrester 11 can quickly extinguish an uncontrollable fire that may occur in the catalytic sensor 10.

[0051] According to another specific embodiment of the present invention, refer to the attached Figure 1 The system further includes: a fuel purification unit 3, which is arranged on a pipeline between the air outlet of the anode part 2 and the air inlet of the catalytic sensor 10. The fuel purification unit 3 purifies the reacted fuel tail gas that is about to enter the air inlet of the catalytic sensor 10, which is beneficial to the smooth progress of the hydrogen oxidation reaction of the catalytic sensor 10.

[0052] Furthermore, a pressure reducing valve, an air intake valve and a proportional valve (not shown in the figure) etc. may be provided on the pipeline between the fuel supply unit 1 and the anode part 2 and before merging with the fuel recycling loop, and a pressure sensor, a hydrogen flow meter (not shown in the figure) etc. may be provided on the pipeline after merging with the fuel recycling loop to control the purge speed or purge time of the fuel gas of the anode part 2. The functions and connection methods of the above-mentioned components belong to the prior art in this field and will not be described in detail here.

[0053] Furthermore, the pipeline between the air supply unit 6 and the cathode part 8 may also be provided with an air filter, an air flow meter, an air compressor (not shown in the figure), a pressure sensor 7, an intercooler and a humidifier (not shown in the figure), etc., and their functions and connection methods belong to the existing technology in this field and will not be repeated here.

[0054] Furthermore, a tail exhaust pipeline may be provided on the gas outlet side of the cathode part 8 for discharging the reaction tail gas of the cathode part 8 .

[0055] Furthermore, the catalyst used in the catalytic temperature sensor is a catalyst commonly used in the reaction between hydrogen and oxygen, such as platinum.

[0056] In a second aspect of the present invention, the present invention provides a method for controlling the fuel cell system described in the above embodiment. According to an embodiment of the present invention, the above method includes:

[0057] S100: supplying part of the air provided by the air supply unit to the cathode part of the fuel cell stack, and supplying the fuel gas provided by the fuel supply unit to the anode part of the fuel cell stack, so that the air and the fuel gas undergo an electrochemical reaction in the fuel cell stack;

[0058] In this step, when the fuel cell stack is running, fuel is provided to the anode part of the fuel cell stack through a fuel supply unit (such as a hydrogen bottle), and air is provided to the cathode part of the fuel cell stack through an air supply unit, so that the above-mentioned air and the above-mentioned fuel gas undergo an electrochemical reaction inside the fuel cell stack.

[0059] S200: providing part of the fuel tail gas after the reaction to the catalytic sensor through the anode fuel tail gas pipeline, and providing part of the air to the catalytic sensor through the air bypass pipeline to measure the hydrogen concentration in the fuel tail gas discharged from the anode part;

[0060] In this step, a fuel recycling device (such as a hydrogen circulation pump) is used to return part of the reacted fuel tail gas to the air intake side of the above-mentioned anode part, and after mixing with the fuel gas provided by the fuel supply unit, it is reused as fuel gas. Another part of the reacted fuel tail gas is provided to the catalytic temperature sensor (such as a catalyst bearing), and at the same time, a part of the air provided by the above-mentioned air supply unit is supplied to the above-mentioned catalytic temperature sensor. If the hydrogen content in the fuel tail gas exceeds the flammable gas limit, the catalyst surface will oxidize hydrogen and release heat. The heat released by the reaction is conducted to the temperature sensor. The temperature change of the temperature sensor is positively correlated with the concentration of hydrogen in the fuel tail gas (that is, the higher the concentration of hydrogen in the fuel tail gas, the more heat released by the reaction, and the greater the temperature change of the temperature sensor). Therefore, the concentration of hydrogen in the reacted fuel tail gas can be indirectly obtained through the temperature change of the temperature sensor.

[0061] S300: adjusting the purge parameters of the fuel gas in the anode part according to the hydrogen concentration in the fuel tail gas after the reaction, detecting and isolating system faults, alarming or notifying the system, or using an adaptive control strategy to adjust system parameters.

[0062] In this step, the control system uses the hydrogen content measurement as a feedback signal to adjust the purge speed or purge time of the fuel gas in the anode part to maintain the desired hydrogen concentration. If the hydrogen concentration in the fuel tail gas is high, the purge speed or purge time of the fuel gas in the anode part can be appropriately reduced. If the hydrogen concentration in the fuel tail gas is low, the purge speed or purge time of the fuel gas in the anode part can be appropriately increased. In this way, the hydrogen concentration can be ensured to be maintained within the optimal range, the purge loss of the fuel gas is minimized, and the fuel consumption is minimized (depending on the driving cycle, it is reduced by about 1% to 10%).

[0063] At the same time, the system can also detect and isolate faults based on the hydrogen concentration in the fuel exhaust. Specifically, by monitoring the hydrogen content, abnormal fluctuations or deviations that may characterize system failures can be detected. The control system can then initiate a fault detection and isolation algorithm to identify the source of the problem and take appropriate measures to mitigate the problem, such as isolating the faulty component or shutting down the system when necessary.

[0064] The system can also be alerted or notified based on the hydrogen concentration in the fuel exhaust. Specifically, when the hydrogen content reaches a certain predefined threshold, the system can generate an alarm or notification. Timely actions can be taken, such as checking the system for leaks, resolving potential safety issues, or performing maintenance activities.

[0065] Adaptive control strategies can also be used to adjust system parameters based on the hydrogen concentration in the fuel exhaust. Specifically, using the detected hydrogen content as a feedback signal, an adaptive control strategy can be used to continuously adjust system parameters and optimize performance. The control system can dynamically adapt to operating conditions to maintain the desired hydrogen concentration, maximize efficiency, and extend the service life of the fuel cell system.

[0066] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0067] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A fuel cell system, It is characterized in that include: a fuel cell stack having an anode portion adapted to receive fuel from a fuel supply unit and a cathode portion adapted to receive air from an air supply unit; an air bypass line, the air bypass line being in communication with the air supply unit; an anode fuel tail gas pipeline, adapted to discharge fuel tail gas from a fuel outlet of the anode portion; and a catalytic sensor disposed at a connection point between the air bypass line and the anode fuel tail gas line, the air bypass line being adapted to provide air to the catalytic sensor, the catalytic sensor being adapted to measure a hydrogen concentration in a fuel tail gas exhausted from a fuel outlet of the anode portion.

2. The fuel cell system according to claim 1, It is characterized in that The air bypass line is directly connected to an air outlet of a compressor of the fuel cell system.

3. The fuel cell system according to claim 1, It is characterized in that The air bypass line is directly connected to an air outlet of an intercooler of the fuel cell system.

4. The fuel cell system according to claim 1, It is characterized in that The catalytic sensor is a catalytic temperature sensor or a temperature sensor in thermal contact with a catalytic bearing structure.

5. The fuel cell system according to claim 4, It is characterized in that The temperature measured by the catalytic sensor has a predefined correlation with a value of hydrogen concentration in the fuel exhaust.

6. The fuel cell system according to claim 1, It is characterized in that The fuel tail gas from the anode part is communicated with the fuel inlet of the fuel cell stack through a fuel recirculation loop, and the fuel recirculation loop is provided with a fuel recirculation device.

7. The fuel cell system according to claim 2 or 3, It is characterized in that The air bypass pipeline is provided with a flow regulating valve to adjust the amount of air flowing to the catalytic sensor.

8. The fuel cell system according to any one of claims 1 to 6, It is characterized in that The purge line of the anode portion controls a purge parameter of the fuel gas based on a hydrogen concentration signal detected from the fuel tail gas by the catalytic sensor.

9. A method for controlling a fuel cell system according to any one of claims 1 to 8, It is characterized in that include: Supplying part of the air provided by the air supply unit to the cathode part of the fuel cell stack, and supplying the fuel gas provided by the fuel supply unit to the anode part of the fuel cell stack, so that the air and the fuel gas undergo an electrochemical reaction in the fuel cell stack; Providing a portion of the reacted fuel tail gas to a catalytic sensor through an anode fuel tail gas pipeline, and providing a portion of air to the catalytic sensor through an air bypass pipeline to measure the hydrogen concentration in the fuel tail gas exhausted from the anode portion; The purge parameters of the fuel gas at the fuel inlet of the anode part are adjusted according to the hydrogen concentration in the fuel exhaust gas, or the system fault detection and isolation are performed according to the hydrogen concentration in the fuel exhaust gas, or the system is alarmed or notified according to the hydrogen concentration in the fuel exhaust gas, or the system parameters are adjusted by an adaptive control strategy according to the hydrogen concentration in the fuel exhaust gas.

10. The method according to claim 9, It is characterized in that The purge parameters include flow rate control, duration control and timing control of the fuel gas.

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