An aeronautical cross-temperature-range proton exchange membrane fuel cell system and control method
Patent Information
- Application Number
- CN202611419172.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-09-14
- Publication Date
- 2026-10-16
AI Technical Summary
[0004]为解决航空跨温区燃料电池电堆的运行温度较高，增湿需求大，常规的增湿方案难以维持稳定气态加湿环境的问题，本申请提供了一种航空跨温区质子交换膜燃料电池系统及控制方法
[0032] By operating the cross-temperature zone fuel cell stack at a temperature greater than 105°C, the stack can operate under high-temperature conditions in aviation, thereby increasing the temperature difference between the stack and the environment, reducing the overall weight of the heat dissipation system, and lowering the battery activation overpotential. The liquid water generated at the cathode outlet of the cross-temperature zone fuel cell stack is recovered using a return pipeline unit. Due to the high operating temperature of the cross-temperature zone fuel cell stack, the recovered water temperature is also high, resulting in a higher saturated vapor pressure. The high-temperature recovered water is then sent to a pressure-relief flash evaporation unit, where it evaporates. This not only ensures sufficient water vapor production but also eliminates the need for an additional heat source. Compared to humidification schemes that require additional heating for vaporization, this application maintains a stable gaseous humidification environment and significantly reduces system energy consumption.
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Figure CN122930971A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of aviation fuel cell technology, and more specifically, to an aviation transtemperature-range proton exchange membrane fuel cell system and control method. Background Technology
[0002] Proton exchange membrane fuel cells (PEMFCs) have shown great potential in the field of hydrogen-powered aviation due to their high energy conversion efficiency and zero emissions. In aviation applications, to improve the heat dissipation temperature difference, the operating temperature of PEMFCs is typically increased, for example, to create cross-temperature range fuel cells operating between 105°C and 120°C. Increasing the operating temperature of the fuel cell not only increases the temperature difference between the fuel cell radiator and the environment, reducing the overall weight of the heat dissipation system, but also lowers the activation overpotential of the cell.
[0003] However, high temperature and low humidity environments can easily cause proton exchange membranes to lose water and dry out, hindering proton transfer, significantly reducing the membrane's proton-carrying capacity, increasing ohmic overpotential, reducing power generation efficiency, and in severe cases, causing membrane damage. When the operating temperature of a fuel cell is high, the dew point temperature of water vapor is also high. When the dew point exceeds 90°C, water will boil under normal pressure, making it impossible to maintain a stable gaseous humidification environment. Therefore, cross-temperature range fuel cell stacks operate at high temperatures and have significant humidification requirements. Conventional humidification methods are insufficient to maintain a stable gaseous humidification environment, becoming a pressing technical problem to be solved in this field. Summary of the Invention
[0004] To address the challenges of high operating temperatures and significant humidification requirements in aviation cross-temperature zone fuel cell stacks, where conventional humidification methods struggle to maintain a stable gaseous humidification environment, this application provides an aviation cross-temperature zone proton exchange membrane fuel cell system and its control method.
[0005] In a first aspect, this application provides an aviation-grade transtemperature-range proton exchange membrane fuel cell system, the aviation-grade transtemperature-range proton exchange membrane fuel cell system comprising:
[0006] A fuel cell assembly, including a cross-temperature stack; the cross-temperature stack operates at a temperature greater than 105°C;
[0007] A hydrogen delivery assembly includes a hydrogen supply line; the hydrogen supply line is connected to the anode inlet of the cross-temperature zone fuel cell stack;
[0008] An air delivery assembly includes an air compressor and an air delivery unit; the outlet of the air compressor, the air delivery unit, and the cathode inlet of the transtemperature zone fuel cell are connected in sequence.
[0009] The air humidification assembly includes an air-water separation unit, a return pipeline unit, a pressure relief flash evaporation unit, and a humidification pipeline unit; the cathode outlet of the cross-temperature zone fuel cell stack, the air-water separation unit, the return pipeline unit, the pressure relief flash evaporation unit, the humidification pipeline unit, and the air supply unit are connected in sequence.
[0010] Optionally, the air humidification assembly further includes a heating unit; the heating unit includes a heating pipe module and a heat exchanger module; the heating pipe module is connected to the hot side channel of the heat exchanger module; the return pipe unit is connected to the cold side channel of the heat exchanger module.
[0011] Optionally, the heating pipeline module includes a coolant discharge pipeline, a coolant supply pipeline, and a radiator; the coolant outlet of the cross-temperature zone fuel cell stack, the coolant discharge pipeline, the hot edge channel of the heat exchanger module, the radiator, the coolant supply pipeline, and the coolant inlet of the cross-temperature zone fuel cell stack are connected in sequence.
[0012] Optionally, the pressure relief flash evaporation unit includes a first flash evaporator, a first throttle valve, a second flash evaporator, and a second throttle valve; the return pipeline unit includes a first drain pipe and a second drain pipe; the gas-liquid separation unit, the first drain pipe, the first throttle valve, the first flash evaporator, and the humidification pipeline unit are connected in sequence; the outlet of the first throttle valve, the second drain pipe, the second flash evaporator, and the humidification pipeline unit are connected in sequence.
[0013] Optionally, the humidification pipeline unit includes a humidification pipeline module and an ejector module; the humidification pipeline module is connected to the ejector port of the ejector module and the steam outlet of the pressure relief flash evaporation unit, respectively; the main channel of the ejector module is connected to the gas delivery unit.
[0014] Optionally, the transtemperature zone fuel cell stack includes a proton exchange membrane, a cathode catalyst layer, an anode catalyst layer, a cathode bipolar plate, and an anode bipolar plate; the proton exchange membrane is located between the cathode catalyst layer and the anode catalyst layer; the cathode bipolar plate is located on the side of the cathode catalyst layer opposite to the proton exchange membrane; and the anode bipolar plate is located on the side of the anode catalyst layer opposite to the proton exchange membrane.
[0015] The cathode catalyst layer includes a hydrophilic region, a first hydrophobic region, and a superhydrophobic region arranged sequentially from the cathode inlet to the cathode outlet; the hydrophilicity of the hydrophilic region, the first hydrophobic region, and the superhydrophobic region decreases sequentially.
[0016] The anode catalyst layer includes a second hydrophobic region; the second hydrophobic region has the same hydrophilicity as the first hydrophobic region.
[0017] In a second aspect, this application provides a control method for an aviation-grade transtemperature-range proton exchange membrane fuel cell, applied to an aviation-grade transtemperature-range proton exchange membrane fuel cell system as described in any one of the first aspects, the method comprising:
[0018] In response to a battery start-up command, the operating parameters of the cross-temperature zone fuel cell stack are acquired; the operating parameters include the dry air flow rate and operating temperature at the air compressor outlet.
[0019] The humidification parameters are determined based on the operating parameters; the humidification parameters include water vapor flow rate and water vapor dew point.
[0020] According to the humidification parameters, the air humidification component is controlled to supply water vapor to the air delivery unit through pressure relief flash evaporation.
[0021] Optionally, the method further includes:
[0022] When the cross-temperature zone fuel cell is in a membrane dry fault, the flight status of the aircraft is obtained;
[0023] The humidification strategy is determined based on the flight conditions; wherein, the power value of the cross-temperature zone fuel cell corresponding to the flight conditions is positively correlated with the dew point of the water vapor supplied by the air humidification component; the dew point of the water vapor supplied by the air humidification component does not exceed the operating temperature of the cross-temperature zone fuel cell from -2°C to 5°C.
[0024] The flight altitude corresponding to the flight condition is positively correlated with the dew point of the water vapor supplied by the air humidification component.
[0025] Optionally, determining the humidification strategy based on the flight conditions includes:
[0026] When the aircraft is in a climb flight condition, the opening of the water vapor outlet of the first flash evaporator of the air humidification assembly is increased, and the opening of the water vapor outlet of the second flash evaporator of the air humidification assembly is decreased; wherein, the water vapor dew point of the first flash evaporator is greater than the water vapor dew point of the second flash evaporator;
[0027] When the aircraft is in cruise flight mode, the opening of the water vapor outlet of the second flash evaporator of the air humidification assembly is increased, and the opening of the water vapor outlet of the first flash evaporator of the air humidification assembly is decreased.
[0028] Optionally, determining the humidification strategy based on the flight conditions further includes:
[0029] When the aircraft is in a climb flight condition, the water inlet temperature of the first flash evaporator of the air humidification assembly is increased, and the water inlet temperature of the second flash evaporator of the air humidification assembly is decreased; wherein, the water vapor dew point of the first flash evaporator is greater than the water vapor dew point of the second flash evaporator;
[0030] When the aircraft is in cruise flight mode, the water inlet temperature of the second flash evaporator of the air humidification assembly is increased, and the water inlet temperature of the first flash evaporator of the air humidification assembly is decreased.
[0031] To address the challenges posed by the high operating temperatures and significant humidification requirements of aviation-grade cross-temperature fuel cell stacks, where conventional humidification methods struggle to maintain a stable gaseous humidification environment, this application offers the following advantages:
[0032] By operating the cross-temperature zone fuel cell stack at a temperature greater than 105°C, the stack can operate under high-temperature conditions in aviation, thereby increasing the temperature difference between the stack and the environment, reducing the overall weight of the heat dissipation system, and lowering the battery activation overpotential. The liquid water generated at the cathode outlet of the cross-temperature zone fuel cell stack is recovered using a return pipeline unit. Due to the high operating temperature of the cross-temperature zone fuel cell stack, the recovered water temperature is also high, resulting in a higher saturated vapor pressure. The high-temperature recovered water is then sent to a pressure-relief flash evaporation unit, where it evaporates. This not only ensures sufficient water vapor production but also eliminates the need for an additional heat source. Compared to humidification schemes that require additional heating for vaporization, this application maintains a stable gaseous humidification environment and significantly reduces system energy consumption. Attached Figure Description
[0033] Figure 1 A schematic diagram of the structure of an aviation transtemperature zone proton exchange membrane fuel cell system according to one embodiment is shown;
[0034] Figure 2 A schematic diagram of an aviation transtemperature zone proton exchange membrane fuel cell system according to another embodiment is shown;
[0035] Figure 3 A schematic diagram of the structure of a transtemperature zone fuel cell stack according to one embodiment is shown;
[0036] Figure 4 A schematic diagram of the airflow path on the side of the cathode bipolar plate near the cathode catalyst layer in one embodiment is shown.
[0037] Figure 5 A schematic diagram of the coolant flow path on the side of the cathode bipolar plate near the adjacent anode bipolar plate in one embodiment is shown.
[0038] Figure 6 A schematic diagram of the hydrogen flow path on the side of the anode bipolar plate near the anode catalyst layer in one embodiment is shown.
[0039] Figure 7 A schematic flowchart of an embodiment of an aviation transtemperature zone proton exchange membrane fuel cell control method is shown.
[0040] Reference numerals: 10, Fuel cell assembly; 11, Transtemperature stack; 111, Proton exchange membrane; 112, Cathode catalyst layer; 113, Anode catalyst layer; 114, Cathode bipolar plate; 115, Anode bipolar plate; 12, Controller; 20, Hydrogen delivery assembly; 21, Hydrogen supply line; 22, Hydrogen return line; 30, Air delivery assembly; 31, Air compressor; 32, Air delivery unit; 40, Air humidification assembly; 41 42. Gas-water separation unit; 42. Return pipeline unit; 421. First drain pipe; 422. Second drain pipe; 43. Pressure relief flash evaporation unit; 431. First flash evaporator; 432. First throttle valve; 433. Second flash evaporator; 434. Second throttle valve; 44. Humidification pipeline unit; 441. Humidification pipeline module; 442. Ejector module; 45. Heating unit; 451. Heating pipeline module; 452. Heat exchanger module. Detailed Implementation
[0041] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, and are not intended to imply any limitation on the scope of the disclosure.
[0042] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments and are not intended to limit the indicated devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.
[0043] In related technologies, the intake humidification of aviation fuel cells mostly adopts membrane tube humidifiers or external heater vaporization schemes: membrane tube humidifiers rely on the pressure difference across the membrane to allow liquid water to permeate to the air side. However, due to the limitations of the membrane material's temperature resistance and permeation limit, it is not easy to obtain a high water vapor partial pressure in high temperature and temperature ranges. External heaters use electric heating to vaporize liquid water through phase change. Although a higher dew point can be obtained, it requires continuous consumption of onboard electrical energy.
[0044] High temperature and low humidity environments easily cause proton exchange membranes to lose water and dry out, hindering proton transfer, significantly reducing the membrane's proton-carrying capacity, increasing ohmic overpotential, decreasing power generation efficiency, and in severe cases, leading to membrane damage. When the operating temperature of a fuel cell is high, the dew point temperature of water vapor is also high. When the dew point exceeds 90°C, water will boil under normal pressure, making it impossible to maintain a stable gaseous humidification environment. Traditional membrane tube humidification devices have insufficient temperature resistance at high temperatures and limited permeation limits, making it difficult to achieve high water vapor partial pressures greater than 90 kPa. Therefore, the high operating temperature of cross-temperature zone fuel cell stacks and the significant humidification requirements, coupled with the difficulty of maintaining a stable gaseous humidification environment using conventional humidification solutions, have become a pressing technical problem to be solved in this field.
[0045] Example 1:
[0046] This embodiment provides an aviation-grade transtemperature-range proton exchange membrane fuel cell system. For example... Figure 1 As shown, the aerospace transtemperature proton exchange membrane fuel cell system includes a fuel cell assembly 10, a hydrogen delivery assembly 20, an air delivery assembly 30, and an air humidification assembly 40. The hydrogen delivery assembly 20 supplies hydrogen to the anode inlet of the fuel cell assembly 10, and the air delivery assembly 30 supplies air to the cathode inlet of the fuel cell assembly 10. The air humidification assembly 40 humidifies the air entering the cathode inlet.
[0047] The fuel cell assembly 10 includes a transtemperature zone stack 11, which operates at a temperature greater than 105°C. The higher operating temperature of the transtemperature zone stack 11 not only increases the temperature difference between the transtemperature zone stack 11 and the ambient heat dissipation, reducing the overall heat dissipation weight, but also reduces the activation overpotential of the transtemperature zone stack 11.
[0048] The hydrogen delivery assembly 20 includes a hydrogen supply line 21, which is connected to the anode inlet of the cross-temperature zone fuel cell stack 11 to continuously supply hydrogen fuel to the anode of the fuel cell stack. The air delivery assembly 30 includes an air compressor 31 and an air delivery unit 32. The outlet of the air compressor 31, the air delivery unit 32, and the cathode inlet of the cross-temperature zone fuel cell stack 11 are connected in sequence. Air is compressed by the air compressor 31 and sent to the cathode through the air delivery unit 32 to participate in the electrochemical reaction.
[0049] The air humidification assembly 40 includes an air-water separation unit 41, a return pipeline unit 42, a pressure relief flash evaporation unit 43, and a humidification pipeline unit 44. The cathode outlet of the cross-temperature zone stack 11, the air-water separation unit 41, the return pipeline unit 42, the pressure relief flash evaporation unit 43, the humidification pipeline unit 44, and the air supply unit 32 are connected in sequence, thereby recovering the liquid water produced at the cathode outlet and sending it into the humidification process.
[0050] In this embodiment, water from the cathode outlet of the cross-temperature zone fuel cell stack 11 is recovered through the return pipeline unit 42. Since the operating temperature of the cross-temperature zone fuel cell stack 11 is high, the temperature of the recovered water is also high. The high-temperature water has a high saturated vapor pressure, thus the water is evaporated through the pressure relief flash evaporation unit 43 using a pressure relief flash evaporation method. This ensures the output of water vapor. Moreover, compared to humidification schemes that use additional heating for vaporization, this embodiment not only maintains a stable gaseous humidification environment but also effectively reduces system energy consumption.
[0051] Furthermore, such as Figure 1 As shown, the air humidification assembly 40 also includes a heating unit 45, which includes a heating pipe module 451 and a heat exchanger module 452. The heating pipe module 451 is connected to the hot side channel of the heat exchanger module 452, and the return pipe unit 42 is connected to the cold side channel of the heat exchanger module 452. In this embodiment, the heating unit 45 further heats the water recovered from the cathode, which can further increase the water temperature, increase the saturated vapor pressure of the water, and thus improve the flash evaporation rate during the pressure relief flash evaporation process.
[0052] Furthermore, such as Figure 1 and Figure 2 As shown, the heating piping module 451 includes a coolant discharge pipe, a coolant supply pipe, and a radiator. The coolant outlet of the cross-temperature zone fuel cell stack 11, the coolant discharge pipe, the hot-side channel of the heat exchanger module 452, the radiator, the coolant supply pipe, and the coolant inlet of the cross-temperature zone fuel cell stack 11 are sequentially connected. The radiator can be one or more combinations of an air-cooled radiator, a liquid-cooled plate, or heat dissipation fins to dissipate excess heat from the circulating coolant to the environment. This embodiment utilizes the heat from the coolant in the cross-temperature zone fuel cell stack 11 to increase the temperature of the recycled water, thereby improving the system's energy utilization rate and reducing the weight of the overall heat dissipation equipment.
[0053] In some embodiments, such as Figure 2 As shown, the pressure relief flash evaporation unit 43 includes a first flash evaporator 431, a first throttle valve 432, a second flash evaporator 433, and a second throttle valve 434. The return pipeline unit 42 includes a first drain pipe 421 and a second drain pipe 422. The gas-water separation unit 41, the first drain pipe 421, the first throttle valve 432, the first flash evaporator 431, and the humidification pipeline unit 44 are connected in sequence. The outlet of the first throttle valve 432, the second drain pipe 422, the second flash evaporator 433, and the humidification pipeline unit 44 are connected in sequence. The first throttle valve 432 and the second throttle valve 434 throttle and depressurize the return water entering the corresponding flash evaporator, reducing the ambient pressure of the water body, so that the water temperature is higher than the saturation boiling point corresponding to the depressurized pressure, thereby causing flash evaporation to generate water vapor.
[0054] The first throttle valve 432 and the second throttle valve 434 can be one or more of electromagnetic throttle valves or proportional throttle valves. The first flash evaporator 431 and the second flash evaporator 433 respectively supply water vapor to the gas supply unit 32 through the humidification pipeline unit 44. The water vapor dew point of the first flash evaporator 431 is higher than that of the second flash evaporator 433. Through the synergy of the two flash evaporators, dynamic adjustment of high dew point and low dew point humidification can be achieved to match the humidification requirements of the fuel cell stack under different operating conditions.
[0055] In some embodiments, such as Figure 2 As shown, the humidification piping unit 44 includes a humidification piping module 441 and an ejector module 442. The humidification piping module 441 is connected to the ejector port of the ejector module 442 and the steam outlet of the pressure relief flash evaporation unit 43, respectively. The main channel of the ejector module 442 is connected to the gas supply unit 32. The humidification piping module 441 collects the water vapor produced by the pressure relief flash evaporation unit 43 and sends it to the ejector port of the ejector module 442. The ejector module 442 uses the ejection effect of the main airflow of the gas supply unit 32 to draw in the water vapor and mix it evenly with the air. The water vapor then enters the cathode inlet of the transtemperature zone stack 11 with the incoming air. The entire process can complete the mixing of steam and air without the need for additional fans or pumps, which is beneficial for simplifying the structure and reducing power consumption.
[0056] In some embodiments, such as Figure 3 As shown, the transtemperature zone fuel cell stack 11 includes a proton exchange membrane 111, a cathode catalyst layer 112, an anode catalyst layer 113, a cathode bipolar plate 114, and an anode bipolar plate 115. The proton exchange membrane 111 is located between the cathode catalyst layer 112 and the anode catalyst layer 113. The cathode bipolar plate 114 is located on the side of the cathode catalyst layer 112 away from the proton exchange membrane 111, and the anode bipolar plate 115 is located on the side of the anode catalyst layer 113 away from the proton exchange membrane 111.
[0057] In the transtemperature zone stack 11, the proton exchange membrane 111, the cathode catalyst layer 112, the anode catalyst layer 113, the cathode bipolar plate 114, and the anode bipolar plate 115 constitute a battery unit. The transtemperature zone stack 11 is composed of multiple battery units connected in series, and the cathode bipolar plates 114 and anode bipolar plates 115 of adjacent battery units are arranged adjacent to each other, and a coolant flow channel is formed between adjacent cathode bipolar plates 114 and anode bipolar plates 115.
[0058] It should be understood that each battery cell also includes a cathode gas diffusion layer, an anode gas diffusion layer, and sealing components.
[0059] The cathode catalyst layer 112 includes a hydrophilic region, a first hydrophobic region, and a superhydrophobic region arranged sequentially from the cathode inlet to the cathode outlet. The hydrophilicity of the hydrophilic region, the first hydrophobic region, and the superhydrophobic region decreases sequentially, allowing the liquid water generated at the cathode to gradually migrate from the hydrophilic region to the superhydrophobic region and be discharged, reducing flooding at the cathode outlet. The anode catalyst layer 113 includes a second hydrophobic region, which has the same hydrophilicity as the first hydrophobic region. This matches the water management characteristics on the anode side with the first hydrophobic region of the cathode, which is beneficial for the coordinated distribution of water between the anode and cathode and reduces the risk of simultaneous membrane dryness at the cathode inlet and flooding at the cathode outlet during cross-temperature operation.
[0060] In some embodiments, such as Figure 4 As shown, the airflow path on the side of the cathode bipolar plate near the cathode catalyst layer flows along the width direction of the cathode bipolar plate, realizing multi-point synchronous replenishment of flash vapor, achieving uniform relative humidity within the cathode bipolar plate, eliminating the dry and wet deviation of the cathode bipolar plate from left to right, matching the gaseous water vapor output from flash humidification, and minimizing local membrane dehydration.
[0061] In some embodiments, such as Figure 5 As shown, the coolant flow path on the side of the cathode bipolar plate closest to the adjacent anode bipolar plate is bent. The bent flow path can extend the heat exchange path of the coolant, increase the heat exchange area, and improve the heat exchange uniformity. It is especially suitable for cross-temperature zone combined with flash humidification scheme, which is conducive to uniform temperature in the cathode bipolar plate, reduces local hot and cold deviations, and thus stabilizes the relative humidity distribution in the membrane electrode surface, reducing the risk of uneven drying and wetting.
[0062] In some embodiments, such as Figure 6 As shown, the hydrogen flow path near the anode catalyst layer on the anode bipolar plate is bent. This extended path prolongs the hydrogen's travel distance, enhancing gas disturbance and allowing hydrogen to uniformly cover the reaction area of the anode catalyst layer, thus improving the uniformity of gas distribution on the anode side. The bent hydrogen flow path, combined with the air flow path and the bent coolant flow path arranged along the width of the cathode plate, facilitates a uniform distribution of temperature and relative humidity within the membrane electrode surface of the cross-temperature zone stack, reducing the risk of localized dehydration or flooding of the proton exchange membrane.
[0063] In some embodiments, such as Figure 2 As shown, the fuel cell assembly 10 also includes a controller 12. The controller 12 can be any of a PLC controller, microcontroller, industrial computer, flight controller, or numerical control system. It is electrically connected to the signal interface of the air compressor 31, the air humidification assembly 40, and the cross-temperature zone fuel cell stack 11. It is used to acquire the operating parameters of the fuel cell stack and generate control commands for the speed of the air compressor 31, the opening degree of the flash evaporator, and the heating unit 45, thereby realizing the automatic adjustment of the humidification process.
[0064] In some embodiments, such as Figure 2As shown, the hydrogen delivery assembly 20 also includes a hydrogen return line 22. The hydrogen return line 22 is connected to the anode outlet of the cross-temperature zone stack 11, and returns unreacted hydrogen on the anode side to the hydrogen supply line 21 for recycling, which helps to improve hydrogen utilization and maintain a stable hydrogen flow rate at the anode inlet.
[0065] In this embodiment of the aviation transtemperature zone proton exchange membrane fuel cell system, hydrogen is supplied to the anode of the transtemperature zone stack 11 by the hydrogen delivery assembly 20, and air is supplied to the cathode by the air delivery assembly 30 via the air compressor 31 and the air delivery unit 32. The air humidification assembly 40 recovers liquid water at the cathode outlet in real time and replenishes water vapor to the air delivery unit 32 by depressurization flash evaporation. When maintenance is required on the heating unit 45 or the flash evaporator, the corresponding pipeline joints and electrical connections can be disconnected, and the heating pipeline module 451 or the depressurization flash evaporation unit 43 can be removed from the air humidification assembly 40 for maintenance. After maintenance, it can be reinstalled, which facilitates the disassembly, assembly and maintenance of the system.
[0066] Example 2:
[0067] like Figure 7 As shown, this embodiment provides a control method for aerospace transtemperature zone proton exchange membrane fuel cells, which includes steps S10 to S30.
[0068] In step S10, in response to the battery start command, the operating parameters of the cross-temperature zone stack 11 are obtained, including the dry air flow rate and operating temperature at the outlet of the air compressor 31.
[0069] In step S20, humidification parameters are determined based on the operating parameters, including water vapor flow rate and water vapor dew point.
[0070] In step S30, the air humidification component 40 is controlled to supply water vapor to the air delivery unit 32 by depressurization flash evaporation according to the humidification parameters, thereby forming a stable gaseous humidification environment before the cathode inlet.
[0071] This embodiment can fully recover and utilize the high-temperature liquid water discharged from the cathode outlet of the cross-temperature zone fuel cell stack 11. Water vaporization is achieved through pressure relief flash evaporation, producing the required water vapor without the need for a high-power additional heat source, and achieving a stable gaseous humidification environment. By matching the humidification parameters in a closed loop according to the real-time operating parameters of the cross-temperature zone fuel cell stack 11, the dew point of the incoming air can be precisely controlled, minimizing fluctuations in the dryness and wetness of the proton exchange membrane 111, reducing the risk of membrane drying and flooding, and improving the stack's output performance and operational stability under cross-temperature zone conditions. Simultaneously, it reduces the heating energy consumption and equipment weight of the airborne humidification system, lightening the aircraft's load burden and meeting the low-power, lightweight application requirements of aviation fuel cells.
[0072] Furthermore, the method also includes steps S40 and S50.
[0073] In step S40, when the cross-temperature zone fuel cell 11 is in a membrane dry fault, the flight conditions of the aircraft are obtained, including the power requirements and flight altitude of the aircraft.
[0074] In step S50, a humidification strategy is determined based on the flight conditions, such that the dew point of the supplied water vapor increases with the power of the transtemperature zone fuel cell stack 11 and with the flight altitude; at the same time, the dew point of the supplied water vapor is constrained to a range not higher than the operating temperature of the transtemperature zone fuel cell stack 11 by -2°C to 5°C, so that the dew point is close to the fuel cell stack temperature without causing condensation.
[0075] Under operating conditions of high temperature across temperature zones, excessive gas, and high power, a higher water vapor dew point can retain sufficient moisture even after the air temperature rises, which is beneficial for protecting the proton exchange membrane 111 on the inlet side of the fuel cell stack and reducing the risk of it drying out due to water loss. Under operating conditions of lower power and more water generation, the dew point is lowered accordingly to reduce the risk of water accumulation at the inlet.
[0076] In some embodiments, step S50 includes steps S51 to S52.
[0077] In step S51, when the aircraft is in climb flight mode, the opening of the water vapor outlet of the first flash evaporator 431 of the air humidification assembly 40 is increased, and the opening of the water vapor outlet of the second flash evaporator 433 of the air humidification assembly 40 is decreased. Since the water vapor dew point of the first flash evaporator 431 is higher than that of the second flash evaporator 433, increasing the opening of the first flash evaporator 431 during climb can increase the overall dew point of the supplied water vapor.
[0078] In step S52, when the aircraft is in cruise flight mode, the opening of the water vapor outlet of the second flash evaporator 433 is increased, and the opening of the water vapor outlet of the first flash evaporator 431 is decreased, so that the overall dew point of the supplied water vapor is correspondingly reduced. Thus, through the dynamic distribution of the opening of the two-stage flash evaporators, flexible adjustment of high dew point and low dew point humidification is achieved to match the humidification requirements under different flight conditions.
[0079] In some embodiments, step S50 further includes steps S53 to S54.
[0080] In step S53, when the aircraft is in a climb flight condition, the inlet water temperature of the first flash evaporator 431 is increased and the inlet water temperature of the second flash evaporator 433 is decreased, so that the water temperature in the first flash evaporator 431 rises and the corresponding water vapor dew point rises, thereby increasing the high dew point humidification capacity.
[0081] In step S54, when the aircraft is in cruise flight mode, the inlet water temperature of the second flash evaporator 433 is increased, and the inlet water temperature of the first flash evaporator 431 is decreased, thereby reducing the overall dew point. The inlet water temperature adjustment and the outlet opening adjustment work together to further refine the dew point control accuracy under different flight conditions.
[0082] In application, the control method of this embodiment first executes step S10 to obtain the operating parameters of the cross-temperature zone fuel cell stack 11 in response to the battery start-up command; then, step S20 is executed to determine the humidification parameters, and step S30 is executed to control the air humidification component 40 to supply water vapor to the air delivery unit 32 in a depressurization flash evaporation manner; when the cross-temperature zone fuel cell stack 11 is detected to be in a membrane dryness fault, the process proceeds to steps S40 and S50, dynamically adjusting the outlet opening and inlet water temperature of the two-stage flash evaporator according to the flight conditions, so that the dew point of the supplied water vapor increases with power and altitude, and the dew point temperature is constrained within the corresponding range of the operating temperature. When the aircraft transitions from cruise to climb or from low altitude to high altitude, this method correspondingly increases the humidification dew point and can maintain a stable gaseous humidification environment under high temperature conditions in the cross-temperature zone.
[0083] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes can be made in form and detail without departing from the scope of this disclosure.
Claims
1. An aerospace transtemperature-range proton exchange membrane fuel cell system, characterized in that, The aerospace transtemperature-range proton exchange membrane fuel cell system includes: A fuel cell assembly, including a cross-temperature stack; the cross-temperature stack operates at a temperature greater than 105°C; A hydrogen delivery assembly includes a hydrogen supply line; the hydrogen supply line is connected to the anode inlet of the cross-temperature zone fuel cell stack; An air delivery assembly includes an air compressor and an air delivery unit; the outlet of the air compressor, the air delivery unit, and the cathode inlet of the transtemperature zone fuel cell are connected in sequence. The air humidification assembly includes an air-water separation unit, a return pipeline unit, a pressure relief flash evaporation unit, and a humidification pipeline unit; the cathode outlet of the cross-temperature zone fuel cell stack, the air-water separation unit, the return pipeline unit, the pressure relief flash evaporation unit, the humidification pipeline unit, and the air supply unit are connected in sequence.
2. The aerospace transtemperature zone proton exchange membrane fuel cell system according to claim 1, characterized in that, The air humidification assembly also includes a heating unit; the heating unit includes a heating pipe module and a heat exchanger module; the heating pipe module is connected to the hot side channel of the heat exchanger module; the return pipe unit is connected to the cold side channel of the heat exchanger module.
3. The aerospace transtemperature zone proton exchange membrane fuel cell system according to claim 2, characterized in that, The heating pipeline module includes a coolant discharge pipeline, a coolant supply pipeline, and a radiator; the coolant outlet of the cross-temperature zone fuel cell stack, the coolant discharge pipeline, the hot edge channel of the heat exchanger module, the radiator, the coolant supply pipeline, and the coolant inlet of the cross-temperature zone fuel cell stack are connected in sequence.
4. The aerospace transtemperature-range proton exchange membrane fuel cell system according to claim 1, characterized in that, The pressure relief flash evaporation unit includes a first flash evaporator, a first throttle valve, a second flash evaporator, and a second throttle valve; the return pipeline unit includes a first drain pipe and a second drain pipe; the gas-water separation unit, the first drain pipe, the first throttle valve, the first flash evaporator, and the humidification pipeline unit are connected in sequence; the outlet of the first throttle valve, the second drain pipe, the second flash evaporator, and the humidification pipeline unit are connected in sequence.
5. The aerospace transtemperature zone proton exchange membrane fuel cell system according to claim 1, characterized in that, The humidification pipeline unit includes a humidification pipeline module and an ejector module; the humidification pipeline module is connected to the ejector port of the ejector module and the steam outlet of the pressure relief flash evaporation unit; the main channel of the ejector module is connected to the gas delivery unit.
6. The aerospace transtemperature-range proton exchange membrane fuel cell system according to claim 1, characterized in that, The transtemperature zone fuel cell stack includes a proton exchange membrane, a cathode catalyst layer, an anode catalyst layer, a cathode bipolar plate, and an anode bipolar plate; the proton exchange membrane is located between the cathode catalyst layer and the anode catalyst layer; the cathode bipolar plate is located on the side of the cathode catalyst layer opposite to the proton exchange membrane; the anode bipolar plate is located on the side of the anode catalyst layer opposite to the proton exchange membrane; The cathode catalyst layer includes a hydrophilic region, a first hydrophobic region, and a superhydrophobic region arranged sequentially from the cathode inlet to the cathode outlet; the hydrophilicity of the hydrophilic region, the first hydrophobic region, and the superhydrophobic region decreases sequentially. The anode catalyst layer includes a second hydrophobic region; the second hydrophobic region has the same hydrophilicity as the first hydrophobic region.
7. A control method for an aerospace transtemperature zone proton exchange membrane fuel cell, applied to an aerospace transtemperature zone proton exchange membrane fuel cell system according to any one of claims 1-6; characterized in that, The method includes: In response to a battery start-up command, the operating parameters of the cross-temperature zone fuel cell stack are acquired; the operating parameters include the dry air flow rate and operating temperature at the air compressor outlet. The humidification parameters are determined based on the operating parameters; the humidification parameters include water vapor flow rate and water vapor dew point. According to the humidification parameters, the air humidification component is controlled to supply water vapor to the air delivery unit through pressure relief flash evaporation.
8. The control method for an aerospace transtemperature-range proton exchange membrane fuel cell according to claim 7, characterized in that, The method further includes: When the cross-temperature zone fuel cell is in a membrane dry fault, the flight status of the aircraft is obtained; The humidification strategy is determined based on the flight conditions; wherein, the power value of the cross-temperature zone fuel cell corresponding to the flight conditions is positively correlated with the dew point of the water vapor supplied by the air humidification component; the dew point of the water vapor supplied by the air humidification component does not exceed the operating temperature of the cross-temperature zone fuel cell from -2°C to 5°C. The flight altitude corresponding to the flight condition is positively correlated with the dew point of the water vapor supplied by the air humidification component.
9. A control method for an aerospace transtemperature-range proton exchange membrane fuel cell according to claim 8, characterized in that, Determining the humidification strategy based on the flight conditions includes: When the aircraft is in a climb flight condition, the opening of the water vapor outlet of the first flash evaporator of the air humidification assembly is increased, and the opening of the water vapor outlet of the second flash evaporator of the air humidification assembly is decreased; wherein, the water vapor dew point of the first flash evaporator is greater than the water vapor dew point of the second flash evaporator; When the aircraft is in cruise flight mode, the opening of the water vapor outlet of the second flash evaporator of the air humidification assembly is increased, and the opening of the water vapor outlet of the first flash evaporator of the air humidification assembly is decreased.
10. A control method for an aerospace transtemperature-range proton exchange membrane fuel cell according to claim 8, characterized in that, The step of determining the humidification strategy based on the flight conditions also includes: When the aircraft is in a climb flight condition, the water inlet temperature of the first flash evaporator of the air humidification assembly is increased, and the water inlet temperature of the second flash evaporator of the air humidification assembly is decreased; wherein, the water vapor dew point of the first flash evaporator is greater than the water vapor dew point of the second flash evaporator; When the aircraft is in cruise flight mode, the water inlet temperature of the second flash evaporator of the air humidification assembly is increased, and the water inlet temperature of the first flash evaporator of the air humidification assembly is decreased.