Working condition control method, device and electronic equipment of fuel cell system

Abstract

The application relates to the technical field of batteries and discloses a working condition control method and device of a fuel cell system and electronic equipment, the method comprising the following steps: determining whether the system power of the fuel cell system meets the vehicle power limit; in response to the system power meeting the vehicle power limit, determining whether the voltage of the fuel cell stack meets the system voltage constraint; in response to the voltage of the fuel cell stack meeting the system voltage constraint, determining whether the system power of the fuel cell system and the voltage of the fuel cell stack reach a stable state within a preset time interval; and in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching the stable state within the preset time interval, controlling the humidity control device to maintain humidification operation on the fuel cell stack, so that the real-time working condition of the fuel cell is maintained in a water flooding state. Therefore, the method can reduce the average single-piece voltage, reduce the output power of the fuel cell stack and prolong the service life of the fuel cell stack.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a method for controlling the operating conditions of a fuel cell system, a device for controlling the operating conditions of a fuel cell system, an electronic device, and a computer-readable storage medium. Background Technology

[0002] To meet the power requirements of fuel cells in automobiles, the number of individual cells can be increased, or multiple stacks can be connected in series to meet the overall vehicle power requirements. High-power fuel cell systems have high idling power. When the fuel cell charges the battery, the higher net power increases the charging speed of the battery, easily leading to overcharging. High-power fuel cell systems are characterized by high voltage, low water production, and significant gas leakage during idling. Specifically, voltages exceeding 0.8V can cause platinum dissolution in the battery catalyst layer. When the voltage exceeds 1.2V, the carbon corrosion rate of the diffusion layer increases significantly, and the corrosion of the carbon support in the catalyst layer is exacerbated. All of these factors contribute to increased stack degradation and affect the lifespan of the fuel cell system.

[0003] Currently, the idling solution used in China for low-rated power fuel cell systems is a zero-power system solution: increasing the air compressor speed increases the power consumption of auxiliary systems, and by reducing oxygen content, the output power of the fuel cell stack is reduced, ultimately achieving zero system power. To extend the lifespan of the fuel cell and reduce its degradation, this solution can only be used for a short period. However, in high-rated power fuel cell systems, the average single-cell voltage will be higher under idling conditions, resulting in a greater impact on the fuel cell stack compared to low-rated power fuel cell systems. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, the first objective of this invention is to propose a method for controlling the operating conditions of a fuel cell system. Under idling conditions, the water pump and water spray device operate, creating a high-humidity environment in the air circulation loop, accompanied by liquid water entering the fuel cell stack. This flooding phenomenon inside the fuel cell stack reduces the average single-cell voltage at the same current density, thereby reducing the output power of the fuel cell stack and ultimately lowering the output power of the fuel cell system to the upper limit of the vehicle's power requirements. Simultaneously, the average single-cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0005] The second objective of this invention is to provide a condition control device for a fuel cell system.

[0006] The third objective of this invention is to provide an electronic device.

[0007] The fourth objective of this invention is to provide a computer-readable storage medium.

[0008] To achieve the above objectives, a first aspect of the present invention provides a method for controlling the operating conditions of a fuel cell system, comprising: when the fuel cell system is running, in response to receiving an idling condition demand, controlling the current density of the fuel cell stack to a first preset current density, and controlling a humidity control device to perform a humidification operation on the fuel cell stack to make the real-time operating condition of the fuel cell reach a flooded state; determining whether the system power of the fuel cell system meets the vehicle power limit; in response to the system power meeting the vehicle power limit, determining whether the voltage of the fuel cell stack meets the system voltage constraint; in response to the voltage of the fuel cell stack meeting the system voltage constraint, determining whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval; and in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within the preset time interval, controlling the humidity control device to maintain the humidification operation on the fuel cell stack to keep the real-time operating condition of the fuel cell in a flooded state.

[0009] In addition, the operating condition control method for the fuel cell system according to the above embodiments of the present invention may also have the following additional technical features:

[0010] According to some embodiments of the present invention, controlling the humidity control device to perform a humidification operation on the fuel cell stack to bring the real-time operating condition of the fuel cell to a flooded state includes: controlling the closure of a bypass valve to cut off the introduction of a dry air source; controlling the activation of a water pump to draw stored water from a water source and deliver it to a water spraying device; controlling the activation of the water spraying device to spray the stored water onto the fuel cell stack to perform a humidification operation on the fuel cell stack; determining whether the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack reaches a first preset range; and determining that the real-time operating condition of the fuel cell has reached a flooded state in response to the impedance phase angle of the electrochemical impedance spectrum reaching the first preset range.

[0011] According to some embodiments of the present invention, the above method further includes: determining that the real-time operating condition of the fuel cell has reached a normal state in response to the impedance phase angle of the electrochemical impedance spectrum reaching a second preset range.

[0012] According to some embodiments of the present invention, the above method further includes: determining that the real-time operating condition of the fuel cell has reached the membrane dry state in response to the impedance phase angle of the electrochemical impedance spectrum reaching a third preset range.

[0013] According to some embodiments of the present invention, the first preset range is larger than the second preset range, and the second preset range is larger than the third preset range.

[0014] According to some embodiments of the present invention, the above method further includes: in response to receiving a request to remove the idling condition, controlling the current density of the fuel cell stack to a second preset current density, and controlling the humidity control device to perform a dehumidification operation on the fuel cell stack so that the real-time operating condition of the fuel cell is removed from the flooded state.

[0015] According to some embodiments of the present invention, controlling a humidity control device to perform a dehumidification operation on a fuel cell stack to remove the fuel cell from a flooded state in real time includes: controlling the shutdown of a water pump and a water spray device, controlling the opening of a bypass valve to perform a dehumidification operation on the fuel cell stack; determining whether the impedance phase angle of the electrochemical impedance spectrum is within a first preset range; responding to the impedance phase angle of the electrochemical impedance spectrum being within the first preset range, controlling the increase of the air compressor speed; responding to the impedance phase angle of the electrochemical impedance spectrum not being within the first preset range, controlling the shutdown of the bypass valve, and determining whether the impedance phase angle of the electrochemical impedance spectrum is within a third preset range; responding to the impedance phase angle of the electrochemical impedance spectrum being within the third preset range, controlling the opening of a water pump and a water spray device until the impedance phase angle of the electrochemical impedance spectrum is within a second preset range.

[0016] According to an embodiment of the present invention, a method for controlling the operating conditions of a fuel cell system includes: during operation of the fuel cell system, in response to receiving an idling condition demand, controlling the current density of the fuel cell stack to a first preset current density, and controlling a humidity control device to humidify the fuel cell stack to achieve a flooded state in the real-time operating condition of the fuel cell; determining whether the system power of the fuel cell system meets the vehicle power limit; in response to the system power meeting the vehicle power limit, determining whether the voltage of the fuel cell stack meets the system voltage constraint; in response to the voltage of the fuel cell stack meeting the system voltage constraint, determining whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval; and in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within the preset time interval, controlling the humidity control device to maintain the humidification operation on the fuel cell stack to maintain the flooded state in the real-time operating condition of the fuel cell. Thus, this method, by operating the water pump and water spray device under idling conditions, creates a high-humidity environment in the air circulation loop, and liquid water enters the fuel cell stack. The internal structure of the fuel cell stack is flooded, reducing the average single-cell voltage at the same current density, thus reducing the output power of the fuel cell stack, thereby causing the output power of the fuel cell system to decrease to the upper limit of the vehicle power requirement. At the same time, the average single-cell voltage will also be reduced to 0.85V, which will reduce platinum and carbon corrosion caused by high voltage, reduce fuel cell stack decay, extend fuel cell stack life, and meet the requirements of the whole vehicle.

[0017] The second objective of this invention is to provide a fuel cell system operating condition control device. During idling, the water pump and water spray device operate, creating a high-humidity environment in the air circulation loop, and liquid water enters the fuel cell stack. This flooding of the fuel cell stack reduces the average cell voltage at the same current density, thus lowering the fuel cell stack's output power and ultimately reducing the fuel cell system's output power to the upper limit required by the vehicle's power requirements. Simultaneously, the average cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0018] To achieve the above objectives, a second aspect of the present invention provides a fuel cell system operating condition control device, comprising: a control module configured to, in response to receiving an idling condition demand during fuel cell system operation, control the current density of the fuel cell stack to a first preset current density and control a humidity control device to perform humidification operation on the fuel cell stack so that the real-time operating condition of the fuel cell reaches a flooded state; a determination module configured to determine whether the system power of the fuel cell system meets the vehicle power limit; a first response module configured to, in response to the system power meeting the vehicle power limit, determine whether the voltage of the fuel cell stack meets the system voltage constraint; a second response module configured to, in response to the fuel cell stack voltage meeting the system voltage constraint, determine whether the system power of the fuel cell system and the voltage of the fuel cell stack reach a stable state within a preset time interval; and a third response module configured to, in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within the preset time interval, control the humidity control device to maintain the humidification operation on the fuel cell stack so that the real-time operating condition of the fuel cell remains in a flooded state.

[0019] According to an embodiment of the present invention, a fuel cell system operating condition control device includes: a control module configured to, during fuel cell system operation, in response to receiving an idling condition demand, control the current density of the fuel cell stack to a first preset current density and control a humidity control device to humidify the fuel cell stack to achieve a flooded state in real-time operating conditions; a determination module configured to determine whether the system power of the fuel cell system meets the vehicle power limit; a first response module configured to, in response to the system power meeting the vehicle power limit, determine whether the voltage of the fuel cell stack meets the system voltage constraint; a second response module configured to, in response to the fuel cell stack voltage meeting the system voltage constraint, determine whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval; and a third response module configured to, in response to the fuel cell system power and the voltage of the fuel cell stack reaching a stable state within the preset time interval, control the humidity control device to maintain the humidification operation on the fuel cell stack to maintain a flooded state in real-time operating conditions. Thus, this device, during idling conditions, operates a water pump and a water spray device, resulting in a high-humidity air circulation loop and the introduction of liquid water into the fuel cell stack. The internal water-flooding phenomenon of the fuel cell stack reduces the average cell voltage at the same current density, thereby lowering the output power of the fuel cell stack and ultimately reducing the output power of the fuel cell system to the upper limit of the vehicle's power requirements. Simultaneously, the average cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0020] To achieve the above objectives, a third aspect of the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described fuel cell system operating condition control method.

[0021] According to the electronic device of the present invention, by executing the above-described fuel cell system operating condition control method, the water pump and water spray device operate during idling, resulting in a high-humidity state in the air circulation loop, and liquid water enters the fuel cell stack. This flooding of the fuel cell stack reduces the average single-cell voltage at the same current density, thereby reducing the output power of the fuel cell stack and ultimately lowering the output power of the fuel cell system to the upper limit of the vehicle's power requirements. Simultaneously, the average single-cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0022] To achieve the above objectives, a fourth aspect of the present invention provides a computer-readable storage medium that stores computer instructions for enabling a computer to implement the above-described fuel cell system operating condition control method.

[0023] According to the computer-readable storage medium of the present invention, by executing the above-described fuel cell system operating condition control method, under idling conditions, the water pump and water spray device operate, the air circulation loop is in a high-humidity state, and liquid water enters the fuel cell stack. The fuel cell stack experiences water flooding, which reduces the average single-cell voltage at the same current density, thereby reducing the output power of the fuel cell stack and causing the output power of the fuel cell system to decrease to the upper limit of the vehicle's power requirements. Simultaneously, the average single-cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0024] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0025] Figure 1 This is a block diagram of a fuel cell system according to some embodiments of the present invention;

[0026] Figure 2 This is a schematic diagram of the signal and control transmission architecture of a fuel cell stack according to some embodiments of the present invention;

[0027] Figure 3 A flowchart of a fuel cell system operating condition control method according to some embodiments of the present invention;

[0028] Figure 4 This is a flowchart of a method for controlling the operating conditions of a fuel cell system according to other embodiments of the present invention;

[0029] Figure 5 This is a flowchart of a method for controlling the operating conditions of a fuel cell system according to some embodiments of the present invention;

[0030] Figure 6 This is a block diagram of a condition control device for a fuel cell system according to some embodiments of the present invention;

[0031] Figure 7 This is a block diagram of an electronic device according to some embodiments of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 100-Fuel cell system, 67-Fuel cell stack, 6-First fuel cell stack, 7-Second fuel cell stack, 20-Water pump, 21-Water spray device, 14-Bypass valve, 15-Humidification device, 13-Three-way valve, 9-Hydrogen circulation pump, 8-Drain valve, 2-Shut-off valve, 3-Proportional valve, 45-Ejector assembly, 4-First ejector, 5-Second ejector, 11-Air compressor, 12-Intercooler, 17-Shut-off valve, 18-Water distributor, 16-Back pressure valve, 19-Water source, 10-Air source, 1-Hydrogen source, 32-DC / DC module, 33-Electrochemical impedance spectroscopy analysis module, and 34-Operating condition control module. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0035] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this invention should have the ordinary meaning understood by those skilled in the art. The terms "first," "second," and similar terms used in the embodiments of this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0036] As described in the background section, to meet the power requirements of fuel cells in automobiles, the number of individual cells can be increased, or multiple stacks can be connected in series to meet the overall vehicle power requirements. High-power fuel cell systems have high idle power. When the fuel cell charges the battery, the higher net power increases the charging speed of the battery, easily leading to overcharging. The idling condition of high-power fuel cell systems is characterized by high voltage, low water production, and large gas permeation. Specifically, a voltage exceeding 0.8V can cause platinum dissolution in the battery catalyst layer. When the voltage exceeds 1.2V, the carbon corrosion decay rate of the diffusion layer increases significantly, and the corrosion of the carbon support in the catalyst layer is aggravated. All of these factors exacerbate stack degradation and affect the lifespan of the fuel cell system. Therefore, the average voltage per cell is generally set to not exceed 0.85V. Since the fuel cell charges the battery at idle, the vehicle requires an upper limit on the idle power demand of the fuel cell to prevent excessively fast charging, which could lead to the battery being fully charged in a short time, resulting in overcharging and potentially causing spontaneous combustion or explosion.

[0037] The higher the rated power of a fuel cell system, the greater its system power at idle. Therefore, for high-rated power fuel cell systems (greater than 300kW), different manufacturers have different standards for idle conditions. Here are two common idle condition settings: 1. Idle condition is set at 0kW system power, where the average single-cell voltage is close to 1V. 2. Idle condition current density is set at 0.1A / cm². 2 Nearby. III. Idle operating condition is set when the average single-chip voltage is less than 0.85V and the system power is less than the set power.

[0038] Regarding the first scenario, the resulting high voltage accelerates platinum dissolution and carbon corrosion, exacerbating the degradation of the fuel cell stack and hindering long-term use. Regarding the second scenario, the idle speed condition is set at a current density of 0.1 A / cm². 2 In the vicinity, this is reasonable for low-rated power fuel cell systems, where the average single-cell voltage is less than 0.85V, which can reduce fuel cell degradation; while in high-rated power fuel cell systems, the current density is 0.1A / cm². 2 Near the catalytic layer, the average voltage of a single cell exceeds 0.85V, accelerating the dissolution of platinum and affecting the catalytic decomposition of hydrogen, thus accelerating fuel cell degradation. Regarding the third scenario mentioned above, it is more applicable to low-rated power fuel cells. However, in high-rated power fuel cell systems, if the average voltage of a single cell is below 0.85V, the fuel cell system power will be too high, exceeding the upper limit of the vehicle's idle power requirement, potentially leading to overcharging of the battery. In summary, the idle power of a high-rated power fuel cell system is constrained by the average voltage of a single cell and the vehicle's idle power requirement.

[0039] In developing this invention, the applicant discovered that the current idling scheme used in China for low-rated-power fuel cell systems is a zero-power scheme: increasing the air compressor speed increases the power consumption of the auxiliary system, and by reducing the oxygen content, the output power of the fuel cell stack is reduced, ultimately achieving zero system power. To extend the lifespan of the fuel cell and reduce its degradation, this scheme can only be used for a short period. However, in high-rated-power fuel cell systems, the average single-cell voltage will be higher under idling conditions, resulting in a greater impact on the fuel cell stack compared to low-rated-power fuel cell systems. Therefore, the above scheme is not suitable for high-rated-power fuel cells.

[0040] Therefore, this invention enables the water pump and spray device to operate under idling conditions, creating a high-humidity environment in the air circulation loop, and introducing liquid water into the fuel cell stack. This flooding of the fuel cell stack reduces the average cell voltage at the same current density, thus lowering the fuel cell stack's output power and ultimately reducing the fuel cell system's output power to the upper limit required by the vehicle's power requirements. Simultaneously, the average cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0041] The following description, with reference to the accompanying drawings, outlines the operating condition control method, operating condition control device, electronic equipment, and storage medium for a fuel cell system according to embodiments of the present invention.

[0042] refer to Figure 1 This is a block diagram of a fuel cell system according to some embodiments of the present invention.

[0043] The fuel cell system 100 of the present invention includes a fuel cell stack 67 and a humidity control device.

[0044] The fuel cell stack 67 includes a first fuel cell stack 6 and a second fuel cell stack 7. The humidity control device includes a water circuit assembly and a gas circuit assembly.

[0045] The water system includes a water pump 20 and a water spraying device 21. The water spraying device 21 can be an atomizing sprayer used to spray water mist onto the fuel cell stack 67 to humidify it. The inlet of the water pump 20 is connected to a water source 19, which can be used to supply water, such as a water tank or a small river. The outlet of the water pump 20 is connected to the inlet of the water spraying device 21, and the spray nozzles of the water spraying device 21 are connected to the first fuel cell stack 6 and the second fuel cell stack 7, respectively.

[0046] The air circuit assembly includes an air circulation loop, a bypass valve 14, and a humidification device 15.

[0047] The air circulation loop includes a three-way valve 13. The inlet of the three-way valve 13 is connected to an air source 10 through the air circulation loop. The air source 10 can be used to provide air, for example, the atmospheric environment. The first outlet of the three-way valve 13 is connected to the air inlet of a bypass valve 14. The air outlet of the bypass valve 14 is connected to the first fuel cell stack 6 and the second fuel cell stack 7, respectively. The second outlet of the three-way valve 13 is connected to the air inlet of a humidification device 15. The humidification device 15 is used to humidify the fuel cell stack 67. For example, the humidification device 15 can be a humidifier. The air outlet of the humidification device 15 is connected to the fuel cell stack 67.

[0048] The fuel cell system 100 also includes a hydrogen recirculation loop.

[0049] The hydrogen circulation loop includes a hydrogen circulation assembly, a hydrogen circulation pump 9, and a drain valve 8. The hydrogen circulation assembly includes a shut-off valve 2, a proportional valve 3, and an ejector assembly 45, which includes a first ejector 4 and a second ejector 5. A hydrogen source 1 is connected to the hydrogen inlet of the fuel cell stack 67 via the hydrogen circulation assembly. The hydrogen source 1 provides hydrogen, for example, from a gas cylinder. The water outlet of the fuel cell stack 67 is connected to the water inlet of the drain valve 8. The outlet of the drain valve 8 is connected to the inlet of the hydrogen circulation pump 9. The outlet of the hydrogen circulation pump 9 is connected to both the first ejector 4 and the second ejector 5. The outlet of the drain valve 8 is connected to a water source 19. The outlet of the hydrogen source 1 is connected sequentially to the inlets of the first ejector 4 and the second ejector 5 via the shut-off valve 2 and the proportional valve 3, respectively. The outlets of the first ejector 4 and the second ejector 5 are connected to the hydrogen inlets of the first fuel cell stack 6 and the second fuel cell stack 7, respectively.

[0050] The air circulation loop also includes an air compressor 11, an intercooler 12, a shut-off valve 17, and a water distributor 18.

[0051] The air inlet of air compressor 11 is connected to air source 10, the air outlet of air compressor 11 is connected to air inlet of intercooler 12, and the air outlet of intercooler 12 is connected to inlet of three-way valve 13. The third outlet of three-way valve 13 is connected to water-air inlet of water distributor 18 through shut-off valve 17, the air outlet of water distributor 18 is connected to air source 10, and the water outlet of water distributor 18 is connected to water source 19.

[0052] The humidity control device also includes a back pressure valve 16, the inlet of which is connected to the humidification device 15, and the outlet of which is connected to the water and air inlet of the water distributor 18.

[0053] The fuel cell system 100 also includes a DC / DC module 32, which is used to record the voltage signal, current signal and stack parameters of the fuel cell stack 67. The stack parameters can include rated power, peak power, current density, voltage efficiency, operating life, maximum operating temperature, operating ambient temperature and thermal stability, etc. The DC / DC module 32 sends the voltage signal, current signal and stack parameters of the fuel cell stack 67 to the electrochemical impedance spectroscopy analysis module 33.

[0054] The fuel cell system 100 also includes an electrochemical impedance spectroscopy analysis module 33, which is used to determine the electrochemical impedance spectrum of the fuel cell stack 67 based on the voltage signal, current signal and stack parameters of the fuel cell stack 67 sent by the DC / DC module 32, and send the electrochemical impedance spectrum to the operating condition control module 34.

[0055] The fuel cell system 100 also includes an operating condition control module 34, which is used to determine the real-time operating condition of the fuel cell stack 67 based on the electrochemical impedance spectroscopy sent by the electrochemical impedance spectroscopy analysis module 33, and to control the humidity control device based on the real-time operating condition so that the real-time operating condition of the fuel cell stack 67 reaches the target operating condition requirement.

[0056] In some embodiments, reference Figure 2 This is a schematic diagram of the signal and control transmission architecture of a fuel cell stack according to some embodiments of the present invention. The voltage signals, current signals, and stack parameters output by the first fuel cell stack 6 and the second fuel cell stack 7 are transmitted to a DC / DC module 32. The DC / DC module 32 transmits the voltage and current signals to a condition control module 34, and the stack parameters to an electrochemical impedance spectroscopy (EIS) analysis module 33. The EIS analysis module 33 processes the stack parameters. The condition control module 34 determines the humidity status of the first fuel cell stack 6 and the second fuel cell stack 7 (mainly determining whether the first fuel cell stack 6 and the second fuel cell stack 7 are flooded or have membrane dryness). When the vehicle demand is transmitted to the condition control module 34, the condition control module 34 processes the signal and transmits it to the DC / DC module 32. Finally, the DC / DC module 32 controls the first fuel cell stack 6 and the second fuel cell stack 7 to output power.

[0057] The system comprises the following components: a first fuel cell stack 6, which converts the chemical energy of hydrogen and oxygen into electrical energy; a second fuel cell stack 7, which converts the chemical energy of hydrogen and oxygen into electrical energy; a water pump 20, which extracts stored water from a water source 19; a water spray device 21, which sprays water mist onto the first and second fuel cell stacks 6 and 7 to humidify them; a bypass valve 14, which regulates the flow rate of coolant to ensure uniform temperature between the first and second fuel cell stacks 6 and 7; a humidification device 15, which humidifies the first and second fuel cell stacks 6 and 7; a three-way valve 13, which controls the flow direction of coolant; a hydrogen circulation pump 9, which circulates unreacted hydrogen from the outlets of the first and second fuel cell stacks 6 and 7 to the inlet to improve hydrogen utilization and simultaneously circulates water vapor to the inlet for humidification; and a drain valve 8, which drains water from the first and second fuel cell stacks 6 and 7. The system includes: a water source 17 for draining water; a shut-off valve 2 for controlling the flow of hydrogen; a proportional valve 3 for adjusting the hydrogen pressure entering the first fuel cell stack 6 and the second fuel cell stack 7 to adapt to different operating conditions; a first ejector 4 for drawing in and emitting unreacted hydrogen and water vapor; a second ejector 5 for drawing in and emitting unreacted hydrogen and water vapor; an air compressor 11 for providing high-pressure air to the first fuel cell stack 6 and the second fuel cell stack 7 to ensure sufficient oxygen supply; an intercooler 12 for reducing the high-temperature air at the outlet of the air compressor 11; a shut-off valve 17 for controlling the flow of air; a water separator 18 for separating moisture from the air to prevent moisture from entering the first fuel cell stack 6 and the second fuel cell stack 7; a back pressure valve 16 for maintaining the pressure stability of the water or gas stored in the fuel cell system 100 to prevent pressure fluctuations; a water source 19 for providing stored water; an air source 10 for providing air; and a hydrogen source 1 for providing hydrogen.

[0058] Therefore, the fuel cell system 100 of the present invention includes a first fuel cell stack 6, a second fuel cell stack 7, a water pump 20, a water spray device 21, a bypass valve 14, a humidification device 15, a three-way valve 13, a hydrogen circulation pump 9, a drain valve 8, a shut-off valve 2, a proportional valve 3, a first ejector 4, a second ejector 5, an air compressor 11, an intercooler 12, a shut-off valve 2, a water distributor 18, a back pressure valve 16, a water source 19, an air source 10, a hydrogen source 1, a DC / DC module 32, an electrochemical impedance spectroscopy analysis module 33, and an operating condition control module 34.

[0059] Hydrogen gas enters the first fuel cell stack 6 and the second fuel cell stack 7 via hydrogen source 1, shut-off valve 2, proportional valve 3, first ejector 4, and second ejector 5. At this point, the mixture exiting the first fuel cell stack 6 and the second fuel cell stack 7 contains hydrogen, nitrogen, water vapor, and liquid water. The liquid water in the exiting mixture is drained into water source 19 via drain valve 8, and the remaining mixture re-enters the first ejector 4 and the second ejector 5 via hydrogen circulation pump 9.

[0060] Air enters through air source 10, passes through air compressor 11, and then enters intercooler 12 before converging into three-way valve 13. One path of three-way valve 13 leads to the first fuel cell stack 6 and the second fuel cell stack 7 via three-way valve 13 or humidification device 15; the other path of three-way valve 13 leads to shut-off valve 17 and water distributor 18, with the gas portion directly discharged into air source 10. The gas discharged from the first fuel cell stack 6 and the second fuel cell stack 7 passes through humidification device 15, back pressure valve 16, and water distributor 18 before finally being discharged back to air source 10, with the liquid water portion entering water source 19.

[0061] The stored water in water source 19 can be pumped into the first fuel cell stack 6 and the second fuel cell stack 7 along with the air through water pump 20 and water spray device 21 as needed for the working conditions. This can meet the vehicle power requirements under idling conditions, and can also greatly reduce the degradation of fuel cells and extend the life of the fuel cell system 100.

[0062] refer to Figure 3 This is a flowchart of a method for controlling the operating conditions of a fuel cell system according to some embodiments of the present invention.

[0063] like Figure 3 As shown, the operating condition control method of the fuel cell system in this embodiment of the invention may include the following steps:

[0064] S301, during fuel cell system operation, in response to receiving an idling condition demand, the current density of the fuel cell stack is controlled to a first preset current density, and the humidity control device is controlled to humidify the fuel cell stack to achieve a water-flooded state in real-time operation. The first preset current density can be set according to actual conditions.

[0065] Specifically, during fuel cell system operation, the vehicle controller sends an idle speed requirement to the operating condition control module. When the operating condition control module receives this requirement, it needs to increase the current density to meet the power output demand of the fuel cell. Therefore, the operating condition control module adjusts the fuel cell output power by changing the current density through a series of operations. Specifically, the operating condition control module controls the DC / DC module to adjust the current density of the fuel cell stack to a first preset current density. To reduce the output power of the fuel cell stack by including liquid water inside, the operating condition control module controls the humidity control device to humidify the fuel cell stack, bringing the real-time operating condition of the fuel cell to a flooded state. A flooded state refers to a fault condition where excessive liquid water accumulates inside the fuel cell stack, causing the gas diffusion layer and catalyst layer to be covered by liquid water, thus hindering the transmission and diffusion of reactant gases (such as hydrogen and oxygen), ultimately affecting the performance of the fuel cell stack.

[0066] S302, determine whether the system power of the fuel cell system meets the vehicle power limit.

[0067] Specifically, after the fuel cell is brought to a flooded state in real time, it is determined whether the system power of the fuel cell system meets the vehicle power limit. When the system power of the fuel cell system meets the vehicle power limit, it can be said that the system power of the fuel cell system has met the requirements. When the system power of the fuel cell system does not meet the vehicle power limit, it can be said that the operating condition control module still needs to adjust the humidity control device to perform humidification operation on the fuel cell stack (i.e., adjust the speed of the water pump and the lift of the water spray device) so that the system power of the fuel cell system meets the requirements.

[0068] S303, in response to the system power meeting the vehicle power limit, determines whether the voltage of the fuel cell stack meets the system voltage constraint.

[0069] Specifically, when the system power of the fuel cell system meets the vehicle power limit, the voltage of the fuel cell stack is checked again to see if it meets the system voltage constraint. If the voltage of the fuel cell stack meets the system voltage constraint, it means that the voltage of the fuel cell stack meets the requirements. If the voltage of the fuel cell stack does not meet the system voltage constraint, it means that the operating condition control module needs to adjust the humidity control device to perform humidification operation on the fuel cell stack (i.e., adjust the speed of the water pump and the lift of the water spray device) so that the voltage of the fuel cell stack meets the system voltage constraint.

[0070] S304, in response to the fuel cell stack voltage satisfying the system voltage constraint, determines whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval.

[0071] Specifically, when the voltage of the fuel cell stack meets the system voltage constraint, it is then determined whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval. When the system power of the fuel cell system and the voltage of the fuel cell stack reach a stable state within the preset time interval, it can be said that the system power of the fuel cell system and the voltage of the fuel cell stack will not change within a certain period of time, and the system power of the fuel cell system and the voltage of the fuel cell stack meet the needs of the fuel cell system. The humidification operation of the humidity control device on the fuel cell stack (i.e., maintaining the speed of the water pump and the lift of the water spray device) is maintained. When the system power of the fuel cell system and the voltage of the fuel cell stack do not reach a stable state within the preset time interval, it can be said that the system power of the fuel cell system and the voltage of the fuel cell stack will still change (increase or decrease). The system power of the fuel cell system and the voltage of the fuel cell stack are unstable, which will affect the service life of the fuel cell. At this time, the humidification operation of the humidity control device on the fuel cell stack (i.e., adjusting the speed of the water pump and the lift of the water spray device) is adjusted.

[0072] S305, in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within a preset time interval, controls the humidity control device to maintain the humidification operation of the fuel cell stack so that the real-time operating condition of the fuel cell remains in a flooded state.

[0073] Specifically, when the system power and voltage of the fuel cell stack reach a stable state within a preset time interval, the operating condition control module controls the humidity control device to maintain humidification of the fuel cell stack to keep the real-time operating condition of the fuel cell in a flooded state, thereby reducing fuel cell stack degradation and extending the life of the fuel cell system. If the system power and voltage of the fuel cell stack do not reach a stable state within the preset time interval, the operating condition control module continues to control the humidity control device to maintain the real-time operating condition of the fuel cell in a flooded state.

[0074] In some embodiments, after the real-time operating condition of the fuel cell reaches a flooded state, it is determined whether the voltage of the fuel cell stack meets the system voltage constraint. If the voltage of the fuel cell stack meets the system voltage constraint, it is determined again whether the system power of the fuel cell system meets the vehicle power limit.

[0075] In some embodiments of the present invention, the humidity control device humidifies the fuel cell stack to bring the real-time operating condition of the fuel cell to a flooded state. This includes: controlling the closure of a bypass valve to cut off the introduction of dry air; controlling the activation of a water pump to draw stored water from a water source and deliver it to a water spraying device; controlling the activation of the water spraying device to spray the stored water onto the fuel cell stack to humidify it; determining whether the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack reaches a first preset range; and determining that the real-time operating condition of the fuel cell has reached a flooded state in response to the impedance phase angle of the electrochemical impedance spectrum reaching the first preset range. The first preset range can be set according to actual conditions.

[0076] Specifically, to reduce the output power of the fuel cell stack by including liquid water inside, the operating condition control module needs to close the bypass valve to stop the introduction of dry air, since a dry air source can reduce the liquid water content inside the fuel cell stack. This requires keeping the humidification device constantly on and controlling the water pump to draw stored water from the water source and deliver it to the spray device, which then sprays the stored water onto the fuel cell stack, making the incoming gas superhumid. This humidification process brings the fuel cell stack to a flooded state, causing it to degrade. At this current density, the voltage decreases, and the output power of the fuel cell stack decreases. Then, the impedance phase angle of the electrochemical impedance spectroscopy (EIS) can be obtained using a lock-in amplifier or a spectrum analyzer. The water content of the fuel cell stack can be determined based on the impedance phase angle: a larger impedance phase angle indicates a higher water content, and a smaller impedance phase angle indicates a lower water content. The impedance phase angle of the electrochemical impedance spectroscopy (EIS) of the fuel cell stack is compared with a first preset range. The EIS analysis module determines whether the impedance phase angle of the fuel cell stack reaches the first preset range. When the impedance phase angle reaches the first preset range, it indicates that the fuel cell stack has a high water content, meaning the water content is sufficient to submerge the fuel cell stack. This can cause the fuel cell to operate in a flooded state, reducing the average single-cell voltage at the same current density and lowering the output power of the fuel cell stack. Consequently, the output power of the fuel cell system is reduced to the upper limit of the vehicle's power requirements. Simultaneously, the average single-cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0077] In some embodiments of the present invention, the method further includes: determining that the real-time operating condition of the fuel cell has reached a normal state in response to the impedance phase angle of the electrochemical impedance spectroscopy reaching a second preset range. The second preset range can be set according to actual conditions.

[0078] Specifically, the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack is compared with a second preset range. The electrochemical impedance spectroscopy analysis module determines whether the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack reaches the second preset range. When the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack reaches the second preset range, it indicates that the water content of the fuel cell stack is neither too much nor too little, that is, the water content of the fuel cell stack cannot submerge the fuel cell stack, so that the real-time operating condition of the fuel cell can reach the normal state.

[0079] In some embodiments of the present invention, the method further includes: determining that the real-time operating condition of the fuel cell has reached the membrane dry state in response to the impedance phase angle of the electrochemical impedance spectroscopy reaching a third preset range. The third preset range can be set according to actual conditions.

[0080] Among them, the first preset range is larger than the second preset range, and the second preset range is larger than the third preset range.

[0081] Specifically, the impedance phase angle of the electrochemical impedance spectroscopy of the fuel cell stack is compared with a third preset range. The electrochemical impedance spectroscopy analysis module determines whether the impedance phase angle of the electrochemical impedance spectroscopy of the fuel cell stack reaches the third preset range. When the impedance phase angle of the electrochemical impedance spectroscopy of the fuel cell stack reaches the third preset range, it indicates that the water content of the fuel cell stack is low, that is, the water content of the fuel cell stack is insufficient to submerge the fuel cell stack. This allows the fuel cell to reach a membrane dry state in real time. The membrane dry state refers to a fault state in which the water content of the proton exchange membrane in the proton exchange membrane fuel cell is too low, resulting in a significant decrease in proton conductivity and affecting the normal operation of the battery.

[0082] In some embodiments of the present invention, the method further includes: in response to receiving a request to remove the idling condition, controlling the current density of the fuel cell stack to a second preset current density, and controlling a humidity control device to perform a dehumidification operation on the fuel cell stack, so that the real-time operating condition of the fuel cell is removed from the flooded state. The second preset current density can be set as needed.

[0083] Specifically, the vehicle controller sends a request to the operating condition control module to release the idling condition. When the operating condition control module receives the request from the vehicle controller, it needs to increase the current density to meet the power output requirement when the vehicle needs the fuel cell to output more power. At this time, the operating condition control module will change the current density through a series of operations to adjust the output power of the fuel cell. That is, the operating condition control module controls the DC / DC module to adjust the current density of the fuel cell stack to the second preset current density. In order to reduce the liquid water contained inside the fuel cell stack, the operating condition control module controls the humidity control device to perform a dehumidification operation on the fuel cell stack to reduce the humidity of the fuel cell stack and remove the real-time operating condition of the fuel cell from the flooded state.

[0084] In some embodiments of the present invention, controlling the humidity control device to perform a dehumidification operation on the fuel cell stack to remove the fuel cell from a flooded state in real time includes: controlling the shutdown of the water pump and the water spray device, controlling the opening of the bypass valve to perform a dehumidification operation on the fuel cell stack; determining whether the impedance phase angle of the electrochemical impedance spectrum is within a first preset range; responding to the impedance phase angle of the electrochemical impedance spectrum being within the first preset range, controlling the increase of the air compressor speed; responding to the impedance phase angle of the electrochemical impedance spectrum not being within the first preset range, controlling the shutdown of the bypass valve, and determining whether the impedance phase angle of the electrochemical impedance spectrum is within a third preset range; responding to the impedance phase angle of the electrochemical impedance spectrum being within the third preset range, controlling the opening of the water pump and the water spray device until the impedance phase angle of the electrochemical impedance spectrum is within a second preset range.

[0085] Specifically, in order to reduce the amount of liquid water inside the fuel cell stack, the operating condition control module needs to control the shutdown of the water pump and the water spraying device to stop the water pump from continuing to pump water and the water spraying device from continuing to spray water onto the fuel cell stack. It also controls the opening of the bypass valve to introduce a dry air source to dry the water inside the fuel cell stack, thus dehumidifying the fuel cell stack. The bypass valve can be equivalent to a "hair dryer". When there is a lot of water in the fuel cell stack, the "hair dryer" can blow air through the water in the fuel cell stack to reduce the humidity of the fuel cell stack. Then, the water content of the fuel cell stack can be determined based on the impedance phase angle of the electrochemical impedance spectroscopy. The impedance phase angle of the fuel cell stack's electrochemical impedance spectroscopy is compared with a first preset range. The electrochemical impedance spectroscopy analysis module determines whether the impedance phase angle of the fuel cell stack's electrochemical impedance spectroscopy reaches the first preset range. When the impedance phase angle of the fuel cell stack's electrochemical impedance spectroscopy reaches the first preset range, it indicates that the fuel cell stack has a high water content, meaning that the water content of the fuel cell stack is enough to submerge the fuel cell stack. In order to prevent the fuel cell from reaching a flooded state in real-time operation, since the higher the speed of the air compressor, the faster the water evaporates inside the fuel cell stack, the speed of the air compressor is increased to increase the drainage rate of the fuel cell stack and reduce the water content of the fuel cell stack. Then, the electrochemical impedance spectroscopy analysis module continues to determine whether the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack is not within the first preset range. When the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack is not within the first preset range, it can be indicated that the humidity of the fuel cell stack has been reduced and the water in the fuel cell stack has been reduced. However, there is still some water inside the fuel cell stack. In order to further reduce the water content of the fuel cell stack, the bypass valve is closed at this time, and a dry air source is introduced to dry the water inside the fuel cell stack.

[0086] The impedance phase angle of the electrochemical impedance spectroscopy is compared with the third preset range. The electrochemical impedance spectroscopy analysis module then determines whether the impedance phase angle of the fuel cell stack's electrochemical impedance spectroscopy is within the third preset range. When the impedance phase angle of the fuel cell stack's electrochemical impedance spectroscopy is within the third preset range, it indicates that the water content of the fuel cell stack is low, meaning that the water content of the fuel cell stack is insufficient to submerge the fuel cell stack. This allows the fuel cell to achieve a membrane dry state in real-time operation. In order to achieve a normal real-time operating state for the fuel cell stack, a humidification operation is required. At this time, the water pump and water spray device are turned on, and the humidification device is kept on at all times. This allows the water pump to draw stored water from the water source and deliver it to the water spray device, so that the water spray device can spray the stored water onto the fuel cell stack to perform a humidification operation. The electrochemical impedance spectroscopy analysis module continues to determine whether the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack is within the second preset range. When the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack is within the second preset range, it indicates that the water content of the fuel cell stack is just right, so that the real-time operating condition of the fuel cell reaches the normal state. At this time, the water pump and the water spraying device are controlled to be turned off, so as to stop the water pump from continuing to pump water and the water spraying device from continuing to spray water onto the fuel cell stack.

[0087] As a specific example, such as Figure 4 As shown in the flowchart, the operating condition control method of the fuel cell system of the present invention may include the following steps:

[0088] S401, in response to receiving an idle condition request.

[0089] S402, control the current density of the fuel cell stack to a first preset current density.

[0090] S403 controls the shut-off of the bypass valve.

[0091] S404 controls the start of the water pump and the start of the water spray device.

[0092] S405, determine whether the system power of the fuel cell system meets the vehicle power limit. If yes, proceed to step S406; if no, proceed to step S408.

[0093] S406, Determine whether the voltage of the fuel cell stack meets the system voltage constraint. If yes, proceed to step S407; if no, proceed to step S408.

[0094] S407. Has the system power of the fuel cell system and the voltage of the fuel cell stack reached a stable state within a preset time interval? If yes, proceed to step S409; if no, proceed to step S408.

[0095] S408, adjusts the speed of the water pump and the lift of the spray device.

[0096] S409 maintains the pump speed and the spray nozzle lift.

[0097] As another specific embodiment, such as Figure 5 As shown in the flowchart, the operating condition control method of the fuel cell system of the present invention may include the following steps:

[0098] S501 responds to receiving a request to cancel idling.

[0099] S502, control the current density of the fuel cell stack to a second preset current density.

[0100] S503 controls the shutdown of the water pump and spray system.

[0101] S504 controls the opening of the bypass valve.

[0102] S505, determine whether the impedance phase angle of the electrochemical impedance spectroscopy is within the first preset range. If yes, proceed to step S506; if no, proceed to step S507.

[0103] S506 controls and increases the speed of the air compressor.

[0104] S507 controls the shut-off of the bypass valve.

[0105] S508, determine whether the impedance phase angle of the electrochemical impedance spectroscopy is within the third preset range. If yes, proceed to step S509; if no, return to step S503.

[0106] S509, control the start of the water pump and water spray device until the impedance phase angle of the electrochemical impedance spectrum is within the second preset range.

[0107] Therefore, flooding can lead to fuel cell stack degradation. However, short-term flooding is recoverable simply by draining the water from the fuel cell stack. This solution satisfies both power and voltage constraints during idling, while also mitigating fuel cell stack degradation and extending the fuel cell system's lifespan. By increasing intake air humidity and introducing liquid water, the fuel cell stack is brought to a flooded state, causing fuel cell degradation and thus reducing the system's voltage and idling power. This prevents high voltage from triggering platinum and carbon degradation in the catalyst layer, while ensuring the idling power meets the vehicle's requirements. Therefore, during normal operation of the fuel cell system, draining excess water to bring the fuel cell stack to a suitable humidity level restores it to its original state. This solution reduces fuel cell degradation while meeting the vehicle's idling power requirements.

[0108] In summary, the fuel cell system operating condition control method according to embodiments of the present invention includes: during fuel cell system operation, in response to receiving an idling condition demand, controlling the current density of the fuel cell stack to a first preset current density, and controlling a humidity control device to humidify the fuel cell stack to achieve a flooded state in the real-time operating condition of the fuel cell; determining whether the system power of the fuel cell system meets the vehicle power limit; in response to the system power meeting the vehicle power limit, determining whether the voltage of the fuel cell stack meets the system voltage constraint; in response to the fuel cell stack voltage meeting the system voltage constraint, determining whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval; and in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within the preset time interval, controlling the humidity control device to maintain the humidification operation on the fuel cell stack to maintain a flooded state in the real-time operating condition of the fuel cell. Thus, this method, by operating the water pump and water spray device during idling, creates a high-humidity environment in the air circulation loop, and liquid water enters the fuel cell stack. The internal water-flooding phenomenon of the fuel cell stack reduces the average cell voltage at the same current density, thereby lowering the output power of the fuel cell stack and ultimately reducing the output power of the fuel cell system to the upper limit of the vehicle's power requirements. Simultaneously, the average cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0109] It should be noted that the method of this embodiment can be executed by a single device, such as a computer or server. The method of this embodiment can also be applied to a distributed scenario, where multiple devices cooperate to complete the task. In such a distributed scenario, one of these devices may execute only one or more steps of the method of this embodiment, and the multiple devices will interact with each other to complete the above method.

[0110] It should be noted that the above description describes some embodiments of the present invention. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims may be performed in a different order than that shown in the above embodiments and still achieve the desired results. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0111] Corresponding to the above embodiments, the present invention also proposes an operating condition control device for a fuel cell system.

[0112] like Figure 6As shown, the operating condition control device of the fuel cell system in this embodiment of the invention includes: a control module 610, a determination module 620, a first response module 630, a second response module 640, and a third response module 650.

[0113] The control module 610 is configured to, during fuel cell system operation, respond to a received idling condition demand, control the current density of the fuel cell stack to a first preset current density, and control the humidity control device to humidify the fuel cell stack to maintain the real-time operating condition of the fuel cell in a flooded state. The determination module 620 is configured to determine whether the system power of the fuel cell system meets the vehicle power limit. The first response module 630 is configured to, in response to the system power meeting the vehicle power limit, determine whether the voltage of the fuel cell stack meets the system voltage constraint. The second response module 640 is configured to, in response to the fuel cell stack voltage meeting the system voltage constraint, determine whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval. The third response module 650 is configured to, in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within a preset time interval, control the humidity control device to maintain the humidification operation of the fuel cell stack to maintain the real-time operating condition of the fuel cell in a flooded state.

[0114] In some embodiments of the present invention, the control module 610 is further configured to: control the closing of the bypass valve to cut off the introduction of dry air source; control the starting of the water pump to draw stored water from the water source and deliver it to the water spraying device; control the starting of the water spraying device to spray the stored water onto the fuel cell stack to humidify the fuel cell stack; determine whether the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack reaches a first preset range; and determine that the real-time operating condition of the fuel cell has reached a flooded state in response to the impedance phase angle of the electrochemical impedance spectrum reaching the first preset range.

[0115] In some embodiments of the present invention, the control module 610 is further configured to: determine that the real-time operating condition of the fuel cell has reached a normal state in response to the impedance phase angle of the electrochemical impedance spectrum reaching a second preset range.

[0116] In some embodiments of the present invention, the control module 610 is further configured to: determine that the real-time operating condition of the fuel cell has reached the membrane dry state in response to the impedance phase angle of the electrochemical impedance spectrum reaching a third preset range.

[0117] In some embodiments of the present invention, the control module 610 is further configured to: in response to receiving a request to remove the idling condition, control the current density of the fuel cell stack to a second preset current density, and control the humidity control device to perform a dehumidification operation on the fuel cell stack so that the real-time operating condition of the fuel cell is removed from the flooded state.

[0118] In some embodiments of the present invention, the control module 610 is further configured to: control the shutdown of the water pump and the water spray device, control the opening of the bypass valve to perform a dehumidification operation on the fuel cell stack; determine whether the impedance phase angle of the electrochemical impedance spectrum is within a first preset range; in response to the impedance phase angle of the electrochemical impedance spectrum being within the first preset range, control the increase of the air compressor speed; in response to the impedance phase angle of the electrochemical impedance spectrum not being within the first preset range, control the shutdown of the bypass valve, and determine whether the impedance phase angle of the electrochemical impedance spectrum is within a third preset range; in response to the impedance phase angle of the electrochemical impedance spectrum being within the third preset range, control the opening of the water pump and the water spray device until the impedance phase angle of the electrochemical impedance spectrum is within a second preset range.

[0119] It should be noted that for details not disclosed in the operating condition control device of the fuel cell system in this embodiment of the invention, please refer to the details disclosed in the operating condition control method of the fuel cell system in this embodiment of the invention, which will not be repeated here.

[0120] In summary, the fuel cell system operating condition control device according to an embodiment of the present invention includes: a control module configured to, during fuel cell system operation, in response to receiving an idling condition demand, control the current density of the fuel cell stack to a first preset current density and control a humidity control device to humidify the fuel cell stack to achieve a flooded state in real-time operating condition; a determination module configured to determine whether the system power of the fuel cell system meets the vehicle power limit; a first response module configured to, in response to the system power meeting the vehicle power limit, determine whether the voltage of the fuel cell stack meets the system voltage constraint; a second response module configured to, in response to the fuel cell stack voltage meeting the system voltage constraint, determine whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval; and a third response module configured to, in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within the preset time interval, control the humidity control device to maintain the humidification operation on the fuel cell stack to maintain a flooded state in real-time operating condition. Thus, this device, during idling condition, operates a water pump and a water spray device, resulting in a high-humidity air circulation loop and the introduction of liquid water into the fuel cell stack. The internal water-flooding phenomenon of the fuel cell stack reduces the average cell voltage at the same current density, thereby lowering the output power of the fuel cell stack and ultimately reducing the output power of the fuel cell system to the upper limit of the vehicle's power requirements. Simultaneously, the average cell voltage also decreases to 0.85V, mitigating platinum and carbon corrosion caused by high voltage, reducing stack degradation, extending stack life, and meeting vehicle requirements.

[0121] For ease of description, the above system is described by dividing it into various modules based on their functions. Of course, in implementing this invention, the functions of each module can be implemented in one or more software and / or hardware components.

[0122] The system described in the above embodiments is used to implement the corresponding method in any of the foregoing embodiments and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0123] Corresponding to the above embodiments, the present invention also proposes an electronic device.

[0124] refer to Figure 7 The diagram below is a block diagram of an electronic device according to some embodiments of the present invention. It illustrates a more specific hardware structure of the electronic device provided in this embodiment. The electronic device may include: a processor 710, a memory 720, an input / output interface 730, a communication interface 740, and a bus 750. The processor 710, memory 720, input / output interface 730, and communication interface 740 are interconnected internally by the bus 750.

[0125] The processor 710 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0126] The memory 720 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 720 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 720 and is called and executed by the processor 710.

[0127] The input / output interface 730 is used to connect input / output modules to enable information input and output. Input / output modules can be configured as components within electronic devices (not shown in the figure) or externally connected to electronic devices to provide corresponding functions. Input electronic devices may include keyboards, mice, touchscreens, microphones, various sensors, etc., while output electronic devices may include displays, speakers, vibrators, indicator lights, etc.

[0128] The communication interface 740 is used to connect a communication module (not shown in the figure) to enable communication between this electronic device and other electronic devices. The communication module can communicate via wired means (e.g., USB, Ethernet cable) or wireless means (e.g., mobile network, Wi-Fi, Bluetooth).

[0129] Bus 750 includes a pathway for transmitting information between various components of an electronic device (e.g., processor 710, memory 720, input / output interface 730, and communication interface 740).

[0130] It should be noted that although the above-described electronic device only shows the processor 710, memory 720, input / output interface 730, communication interface 740, and bus 750, in specific implementations, the electronic device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described electronic device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0131] The electronic devices described above are used to implement the corresponding methods in any of the foregoing embodiments and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0132] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, the present invention also provides a computer-readable storage medium storing computer instructions for causing a computer to perform the methods of any of the above embodiments.

[0133] The aforementioned computer-readable storage medium can be any available medium or data storage device that a computer can access, including but not limited to magnetic storage (e.g., floppy disks, hard disks, magnetic tapes, magneto-optical disks (MOs), etc.), optical storage (e.g., CDs, DVDs, BDs, HVDs, etc.), and semiconductor storage (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND flash), solid-state drives (SSDs)).

[0134] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to perform the methods of any of the above exemplary method sections, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0135] Furthermore, although the operations of the method of the present invention are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in that specific order, or that all of the operations shown must be performed to achieve the desired result. Rather, the steps depicted in the flowchart may be performed in a different order. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0136] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0137] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this invention should have the ordinary meaning understood by those skilled in the art. The terms "first," "second," and similar terms used in the embodiments of this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0138] While the spirit and principles of the invention have been described with reference to several specific embodiments, it should be understood that the invention is not limited to the disclosed specific embodiments, and the division of aspects does not imply that features in these aspects cannot be combined for benefit; such division is merely for ease of description. The invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the appended claims is to be interpreted in the broadest sense, thereby encompassing all such modifications and equivalent structures and functions.

Claims

1. A method for controlling the operating conditions of a fuel cell system, characterized in that, include: When the fuel cell system is running, in response to receiving an idling condition demand, the current density of the fuel cell stack is controlled to a first preset current density, and the humidity control device is controlled to humidify the fuel cell stack so that the real-time operating condition of the fuel cell reaches a water-flooded state; wherein, when the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack reaches a first preset range, the real-time operating condition of the fuel cell reaches a water-flooded state. Determine whether the system power of the fuel cell system meets the vehicle power limit; In response to the system power meeting the vehicle power limit, determine whether the voltage of the fuel cell stack meets the system voltage constraint; In response to the fact that the voltage of the fuel cell stack meets the system voltage constraint, it is determined whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval. In response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within a preset time interval, the humidity control device is controlled to maintain the humidification operation of the fuel cell stack so that the real-time operating condition of the fuel cell remains in the flooded state.

2. The operating condition control method for a fuel cell system according to claim 1, characterized in that, The control of the humidity control device to humidify the fuel cell stack, so that the real-time operating condition of the fuel cell reaches a water-flooded state, includes: Control the shut-off bypass valve to cut off the source of dry air; Control the water pump to start, so that the water pump draws stored water from the water source and delivers it to the water spraying device; The water spray device is activated to spray stored water onto the fuel cell stack to humidify it.

3. The operating condition control method for a fuel cell system according to claim 2, characterized in that, The method further includes: In response to the impedance phase angle of the electrochemical impedance spectrum reaching a second preset range, it is determined that the real-time operating condition of the fuel cell has reached a normal state.

4. The operating condition control method for a fuel cell system according to claim 3, characterized in that, The method further includes: In response to the impedance phase angle of the electrochemical impedance spectrum reaching a third preset range, it is determined that the real-time operating condition of the fuel cell has reached the membrane dry state.

5. The operating condition control method for a fuel cell system according to claim 4, characterized in that, The first preset range is greater than the second preset range, and the second preset range is greater than the third preset range.

6. The operating condition control method for a fuel cell system according to claim 5, characterized in that, The method further includes: In response to receiving a request to remove the idling condition, the current density of the fuel cell stack is controlled to a second preset current density, and the humidity control device is controlled to perform a dehumidification operation on the fuel cell stack so that the real-time operating condition of the fuel cell is removed from the flooded state.

7. The operating condition control method for a fuel cell system according to claim 6, characterized in that, The control of the humidity control device to dehumidify the fuel cell stack, so that the real-time operating condition of the fuel cell is removed from the flooded state, includes: Control the shutdown of the water pump and the water spray device, and control the opening of the bypass valve to perform a dehumidification operation on the fuel cell stack; Determine whether the impedance phase angle of the electrochemical impedance spectrum is within a first preset range; In response to the impedance phase angle of the electrochemical impedance spectrum being within a first preset range, the speed of the air compressor is controlled to be increased. In response to the impedance phase angle of the electrochemical impedance spectrum not being within a first preset range, the bypass valve is controlled to close, and it is determined whether the impedance phase angle of the electrochemical impedance spectrum is within a third preset range. In response to the impedance phase angle of the electrochemical impedance spectrum being within a third preset range, the water pump and the water spray device are controlled to be turned on until the impedance phase angle of the electrochemical impedance spectrum is within a second preset range.

8. A condition control device for a fuel cell system, characterized in that, include: The control module is configured to, when the fuel cell system is running, respond to the received idling condition demand, control the current density of the fuel cell stack to a first preset current density, and control the humidity control device to perform humidification operation on the fuel cell stack so that the real-time operating condition of the fuel cell reaches a water-flooded state; wherein, when the impedance phase angle of the electrochemical impedance spectrum of the fuel cell stack reaches a first preset range, the real-time operating condition of the fuel cell reaches a water-flooded state. The determination module is configured to determine whether the system power of the fuel cell system meets the vehicle power limit; The first response module is configured to determine whether the voltage of the fuel cell stack meets the system voltage constraint in response to the system power meeting the vehicle power limit. The second response module is configured to determine whether the system power of the fuel cell system and the voltage of the fuel cell stack have reached a stable state within a preset time interval in response to the voltage of the fuel cell stack satisfying the system voltage constraint. The third response module is configured to control the humidity control device to maintain the humidification operation on the fuel cell stack in response to the system power of the fuel cell system and the voltage of the fuel cell stack reaching a stable state within a preset time interval, so as to maintain the real-time operating condition of the fuel cell in the flooded state.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the operating condition control method for the fuel cell system as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to enable the computer to implement the operating condition control method of the fuel cell system according to any one of claims 1 to 7.

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