Battery humidification system and vapor generator validation method and battery humidification method

Abstract

This invention discloses a battery humidification system and a steam generator verification method, as well as a battery humidification method. The battery humidification system includes a steam flow supply system, a cathode control loop, an anode control loop, an anode temperature control unit, a cathode temperature control unit, a fuel cell stack, a tailpipe unit, and a control module. The steam flow supply system is configured to supply steam to the fuel cell stack. The steam flow supply system includes a steam generator and at least two steam control branches. The steam generator outlet is connected to at least two steam control branches, one of which merges with the cathode control loop and is connected to the cathode inlet of the fuel cell stack through the cathode temperature control unit; the other steam control branch merges with the anode control loop and is connected to the anode inlet of the fuel cell stack through the anode temperature control unit. All fuel cell stack outlets are connected to the tailpipe unit. The beneficial effects of this invention are: solving the problem of excessively dry or excessively wet fuel cell stacks caused by insufficient response speed and stability in traditional control methods.

Description

Technical Field

[0001] This invention relates to the field of industrial production technology, and in particular to a battery humidification system and a method for verifying a steam generator and a battery humidification method. Background Technology

[0002] In industrial production and testing, steam serves as a crucial heat carrier or process medium, and the stability and dynamic regulation of its supply directly impact product quality, testing accuracy, and production efficiency. This is especially true in proton exchange membrane fuel cell activation testing scenarios, where the fuel cell stack needs to undergo dynamic conditions such as load changes, start-up and shutdown, and high current density scans within a short period, placing extremely high demands on the steam flow response speed and humidity control accuracy.

[0003] However, existing steam control methods primarily achieve flow control through a closed-loop control mode that combines steam generator heating power regulation with proportional valve opening adjustment. While this mode can meet basic requirements under normal steady-state load scenarios, it suffers from significant technical limitations in high-dynamic, variable-flow-rate scenarios such as fuel cell activation testing, directly hindering the consistency between activation results and testing performance.

[0004] Defect 1: Severe dynamic response lag, easily leading to membrane dryness or flooding in the fuel cell stack. Specifically, the vaporization process of water in the steam generator has inherent thermal inertia. After adjusting the heating power, changes in steam output require a heat transfer and vaporization cycle (usually tens of seconds), significantly lagging behind the instantaneous load changes during fuel cell activation. This lag causes two key issues directly affecting stack life and performance: First, insufficient vaporization leads to liquid water entrainment in the steam. Liquid water enters the stack channels with the steam, causing blockage of the gas diffusion layer (flooding), resulting in gas shortage and even impacting the membrane electrode structure. Second, insufficient steam output causes a sudden drop in supply pressure, which in turn causes the humidity control valve's regulation reference to shift. If the humidity is too low, the conductivity of the proton exchange membrane decreases, leading to membrane dryness or even hot spots or perforations (dry burning), directly causing activation failure or irreversible damage to the stack.

[0005] Defect 2: Poor supply stability during multi-condition switching affects the accuracy of test data. Specifically, in the batch activation testing of fuel cells, scenarios such as alternating start-up and shutdown of multiple devices, high-dynamic condition simulation, and accelerated endurance testing lead to frequent load fluctuations. Traditional control methods rely solely on heating power and proportional valve adjustment, which is prone to gas supply pressure surges or large flow fluctuations, resulting in inconsistent activation boundary conditions for the same batch of fuel cell stacks, severely affecting the repeatability and comparability of test data.

[0006] Thirdly, the humidity control accuracy is limited, failing to meet the activation process window requirements. Specifically, the fuel cell activation process has strict window requirements for the steam saturation (i.e., relative humidity) at the stack inlet. Relying solely on closed-loop regulation via proportional valves and flow meters makes it difficult to balance pressure changes and humidity requirements during sudden load changes, easily leading to overshoot or undershoot. Humidity overshoot may cause stack flooding, while excessively low humidity may cause membrane drying; both will prevent the activated stack from reaching its optimal performance.

[0007] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0008] The technical problem to be solved by this invention is: in the activation test of fuel cells, the existing steam control method has a response lag due to thermal inertia, which easily causes the stack membrane to dry out or be flooded, affecting the activation effect and the consistency of the test.

[0009] The present invention solves the above-mentioned technical problems through the following technical means: This invention claims protection for a battery humidification system, including a steam flow supply system, a cathode control circuit, an anode control circuit, an anode temperature control unit, a cathode temperature control unit, a fuel cell stack, an exhaust unit, and a control module; The steam flow supply system is configured to supply steam to the fuel cell stack; the steam flow supply system includes a steam generator and at least two steam control branches, the steam generator outlet being connected to at least two steam control branches, one of which merges with the cathode control loop and is connected to the cathode inlet of the fuel cell stack via a cathode temperature control unit; the other steam control branch merges with the anode control loop and is connected to the anode inlet of the fuel cell stack via an anode temperature control unit; the fuel cell stack outlets are all connected to the tailpipe unit; The control module is configured to trigger the flash process or suppress steam generation in the steam generator based on the steam supply demand; the steam generator is set with a minimum liquid storage capacity, which is set to the flash process, and the pressure drop in the steam generator does not exceed the maximum allowable pressure drop.

[0010] Preferably, an anode flow control unit and an anode preheating unit are provided on the anode control loop.

[0011] The hydrogen flow rate is controlled by the anode flow control unit, and the hydrogen is preheated by the anode preheating unit.

[0012] Preferably, a cathode flow control unit and a cathode preheating unit are provided on the cathode control loop.

[0013] The cathode flow control unit controls the air flow, and the cathode preheating unit preheats the air.

[0014] Preferably, the steam generator is equipped with a heating module and a pressure sensing structure, with the heating module located below the pressure sensing structure.

[0015] Preferably, the steam generator is also equipped with a baffle plate, and the heating module, pressure sensing structure and baffle plate are arranged in sequence from bottom to top.

[0016] Baffles are used to guide the flow of high-temperature water, making the steam generation process more uniform.

[0017] Preferably, a demister is also installed inside the steam generator, and the demister is located above the baffle plate.

[0018] The demister separates liquid droplets from the flash vapor, preventing liquid water from entering the fuel cell stack.

[0019] Preferably, the steam flow supply system also includes a pressure reducing valve. The steam generator outlet is connected to one end of a second pipeline, on which a pressure reducing valve is installed. The other end of the second pipeline is divided into two branches, which are connected to the steam control branch respectively. A steam flow meter and a proportional valve are installed sequentially on each of the steam control branches.

[0020] Preferably, the steam flow supply system also includes a water supply module, which includes a water source supply, a water replenishment pump and a check valve. The water source supply is connected to the steam generator inlet through a first pipeline, and the water replenishment pump and check valve are installed sequentially on the first pipeline.

[0021] The water supply module is used to replenish the water source for the steam generator.

[0022] This invention claims protection for a method for verifying a steam generator used in a battery humidification system, comprising the following steps: The minimum pressure of the steam generator after the flash process is confirmed by the maximum allowable pressure drop; Confirm the gas production rate of the flash evaporation process within the maximum allowable pressure drop range; Confirm the total amount of steam that the flash process needs to replenish instantaneously under extreme operating conditions of sudden changes in steam supply demand; Based on the total steam volume and the gas production rate of the flash evaporation process, the minimum liquid storage capacity of the steam generator is determined.

[0023] This invention claims protection for a battery humidification method using a battery humidification system, comprising the following steps: When the hydrogen flow rate input to the anode circuit and the air flow rate input to the cathode circuit rise to the second flow rate, the control steam generator triggers the flash evaporation process. One steam control branch merges with the cathode control circuit and is adjusted to the target temperature and humidity by the cathode temperature control unit before being introduced into the cathode inlet of the fuel cell stack. The other steam control branch merges with the anode control circuit and is adjusted to the target temperature and humidity by the anode temperature control unit before being introduced into the anode inlet of the fuel cell stack. The exhaust unit processes the exhaust gas. When the hydrogen flow rate input to the anode circuit and the air flow rate input to the cathode circuit decrease to the first flow rate, the steam generator is controlled to suppress steam generation. One steam control branch merges with the cathode control circuit and is adjusted to the target temperature and humidity through the cathode temperature control unit before being introduced into the cathode inlet of the fuel cell stack. The other steam control branch merges with the anode control circuit and is adjusted to the target temperature and humidity through the anode temperature control unit before being introduced into the anode inlet of the fuel cell stack. The exhaust unit processes the exhaust gas.

[0024] The advantages of this invention are: it integrates the functions of steam generator depressurization flash evaporation for energy replenishment, rapid and precise steam supply under multi-loop high dynamic load changes, and steam generator volume optimization into a battery humidification system. Specifically designed for high-dynamic scenarios such as fuel cell durability testing and multi-device batch testing, it solves the problem of fuel cell stacks being too dry or too wet due to insufficient response speed and stability in traditional control methods. This embodiment ensures the long-term operational stability of the fuel cell stack under high dynamic conditions by achieving rapid steam response and precise steam supply, overcoming the limitations of traditional methods that cannot meet the needs of long-term dynamic testing or multi-device collaborative operation, thus restricting their application scope. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the steam flow control system according to Embodiment 1 of the present invention; Figure 2 This is a schematic flowchart of the steam flow control method according to Embodiment 1 of the present invention; Figure 3 This is a flowchart illustrating the steam generator verification method according to Embodiment 3 of the present invention; Figure 4 This is a schematic diagram of the battery humidification system according to Embodiment 4 of the present invention; 10. Steam generator; 100. Heating module; 101. Pressure sensor; 102. Liquid level sensor; 103. Baffle; 104. Demister; 105. Temperature sensor; 11. Water supply module; 110. Water source supply; 111. Make-up water pump; 113. Check valve; 13. Pressure reducing valve; 130. First steam flow meter; 131. Second steam flow meter; 140. First proportional valve; 141. Second proportional valve; 150. First load end; 151. Second load end; 13 n , No. n Steam flow meter; 14 n , No. n Proportional valve; 15 n , No. n Load end; 16. Controller; 2. Cathode circuit; 3. Anode circuit; 4. Fuel cell stack; 5. Cathode tailpipe unit; 6. Anode tailpipe unit; 7. Control module. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1 See Figure 1 This embodiment requires protection of a steam flow control system for realizing multi-loop steam flow control. The system includes a steam generator 10, a water supply module 11, a pressure reducing valve 13, a steam flow meter, a proportional valve, a load terminal, and a controller 16.

[0028] The water supply module 11 is used to supplement the water source for the steam generator 10. Specifically, the water supply module 11 includes a water supply 110, a water replenishment pump 111 and a one-way valve 113. The water supply 110 is connected to the inlet of the steam generator 10 through a first pipeline. The water replenishment pump 111 and the one-way valve 113 are sequentially installed on the first pipeline.

[0029] The steam generator 10 is a custom-made product. By confirming the minimum liquid storage capacity, the maximum pressure drop is stabilized within the allowable range while achieving flash evaporation. The confirmation of the minimum liquid storage capacity is described in Example 2. The steam generator 10 contains, from bottom to top, a heating module 100, a pressure sensor 101, a liquid level sensor 102, a baffle 103, a demister 104, and a temperature sensor 105. The heating module 100 generates high-temperature water; the pressure sensor 101 monitors the pressure within the steam generator 10; the liquid level sensor 102 monitors the water level; and the baffle 103 guides the flow of high-temperature water, making the steam generation process more uniform and preventing violent gas-liquid phase movement that could cause droplet splashing and liquid inflow into the demister 104. The demister 104 separates droplets from the flash steam, preventing liquid water from entering the load end.

[0030] The outlet of steam generator 10 is connected to one end of a second pipeline. A pressure reducing valve 13 is installed on the second pipeline. The other end of the second pipeline is connected in parallel to one or more load terminals through a corresponding branch. The second pipeline is connected to the first load terminal 150 through a first branch. A first steam flow meter 130 and a first proportional valve 140 are installed on the first branch. The second pipeline is connected to the second load terminal 151 through a second branch. A second steam flow meter 131 and a second proportional valve 141 are installed on the second branch... and so on. n Pipeline passes through the first n Branch connection number n Load side 15 n , No. n The branch road is set up with the first n Steam flow meter 13 n and the n Proportional valve 14 n .

[0031] The controller 16 is electrically connected to the water supply pump 111, the liquid level sensor 102, the temperature sensor 105, the pressure sensor 101, the heating module 100, the steam flow meter, and the proportional valve to form a closed-loop control.

[0032] See Figure 2 The steam flow control system is used to control the steam flow process as follows: S 1. System initialization: Specifically, controller 16 starts water pump 111, which injects water into steam generator 10 via check valve 113. After the water level sensor 102 detects that the water level has reached the preset value, water pump 111 stops. Controller 16 then starts heating module 100, and temperature sensor 105 sends water temperature data back to controller 16. The system continues until the water pressure inside steam generator 10 reaches 6... bar Then, pressure reducing valve 13 adjusts the pressure to 5. bar Each proportional valve is at its initial opening, and the steam flow control system enters standby mode.

[0033] S 2. Changes in steam demand at the load end, with the first... n Load side 15 n For example, the controller receives the first... n load side 15n Changes in steam demand: S 3. When the controller receives the first... n Load side 15 n Increased steam demand triggers flash evaporation within steam generator 10; specifically, controller 16 increases the... n Proportional valve 14 nThe steam flow meter provides real-time feedback on the increase in flow rate, while the pressure sensor 101 detects a decrease in pressure inside the steam generator 10. The high-temperature water inside the steam generator 10 triggers flash evaporation. That is, the high-temperature water inside the steam generator 10 triggers flash evaporation due to the decrease in pressure. The baffle 103 reduces the liquid level fluctuation during flash evaporation, captures splashing droplets, and blocks the gas-liquid surge. The generated steam is deliquescent by the demister 104 and then enters the pipeline through the pressure reducing valve 13 to quickly replenish the steam supply.

[0034] S 4. Power matching: The water pressure inside the steam generator 10 gradually rises and stabilizes at the set value. Specifically, the pressure sensor 101 monitors the pressure inside the generator in real time, and the controller 16 increases the power of the heating module 100 based on the pressure changes. As the heating power increases, the evaporation rate rises, and the pressure inside the steam generator 10 gradually rises. The flashing phenomenon gradually weakens, the steam flow control system switches to stable evaporation steam supply, and the internal pressure of the generator gradually rises and stabilizes at 6... bar The steam flow control system maintains a stable steam supply.

[0035] S 5. When the first n Load side 15 n As steam demand decreases, the steam generator 10 is controlled to suppress steam generation; specifically, the... n Load side 15 n The controller 16 receives the command to reduce the flow rate and then reduces the flow rate of the first controller. n Proportional valve 14 n The flow meter provides real-time feedback on the opening degree of the steam generator 10, indicating a decrease in pressure. Pressure sensor 101 detects an increase in pressure inside the steam generator 10. The increase in pressure corresponds to an increase in saturation temperature. At this time, the actual temperature of the water is lower than the saturation temperature under the new pressure, and the water is in a supercooled state. The evaporation and boiling processes are significantly inhibited, and the steam output automatically decreases, avoiding overpressure or steam waste in the steam flow control system.

[0036] S 6. Pressure sensor 101 detects the rise in pressure inside the generator in real time. The controller reduces the power of heating module 100 to match the steam production with the load demand. As the heating power decreases, the pressure inside the generator drops from a high level and stabilizes at the set value, and the system maintains a stable steam supply.

[0037] It is worth mentioning that, in the above process, the controller 16 starts the water supply pump 111 to supply water to the steam generator 10 based on the data from the liquid level sensor 102, maintaining a stable water level; the flow rate at the remaining load ends is controlled by the... n Steam flow meter and the first n Proportional valve 14 n Closed-loop regulation, unaffected by other load fluctuations.

[0038] When all loads stop using steam or total demand drops below the standby threshold, controller 16 will activate each proportional valve 14. n The initial opening is closed, and the power of the heating module 100 is reduced to the standby maintenance power. The steam flow control system then returns to normal. S 1. Standby mode.

[0039] It is worth noting that the load reduction or sudden decrease described above is relative to the values ​​before and after the load change. In actual use, a threshold range can be predetermined to evaluate the rate of load increase and decrease. S 2~ S The description in section 5 is a complete response unit for a single load change. In actual operation, the system will be continuously and cyclically triggered according to specific load requirements. Although the above working process is described using a single load change as an example, the steam flow control method is not limited to flow control for load changes of a single load. Instead, it forms a highly dynamic thermal energy reserve through the flash evaporation process to rapidly supply steam to multiple load ends.

[0040] Furthermore, the load change at the load end is divided into two cases: load surge and load drop. When the load surges, the pressure sensor 101 detects the pressure drop inside the steam generator 10 in real time, and the controller 16 immediately triggers the flash evaporation compensation mechanism. High-temperature water is instantaneously vaporized based on the pressure reduction flash evaporation principle, and the generated supplementary steam is quickly output after demisting treatment, thereby matching the required steam flow increase demand and realizing rapid steam supply.

[0041] When the load suddenly decreases, the pressure sensor 101 detects the upward trend of the system pressure. The controller 16 quickly reduces the power of the heating module 100 to reduce steam generation. On the other hand, the high-temperature water temperature rises due to the pressure increase, and the saturation temperature corresponding to the pressure rises accordingly, so that the actual water temperature is lower than the current saturation temperature. The water is in a supercooled state, thereby inhibiting the evaporation and boiling process, suppressing the generation of excessive steam, avoiding system overpressure and maintaining steam dryness.

[0042] In summary, through controller 16, the... n Proportional valve 14 n The steam flow meter and pressure sensor 101 work together to achieve dynamic switching between flash evaporation and suppression of excessive steam generation; enabling rapid response and allocation of steam demand at multiple load ends.

[0043] Example 2 See Figure 3Based on the rapid steam response process under multi-loop high dynamic load changes in Embodiment 1, this embodiment requires a verification method for protecting the steam generator. By verifying the minimum liquid storage capacity, it ensures that the steam generator 10 has a sufficient amount of high-temperature saturated water. This allows the steam flow control system to achieve rapid steam response under extreme conditions of sudden changes in load demand, while also keeping the pressure drop within the steam generator 10 within an allowable range. This fundamentally solves the inherent contradiction between rapid response and controllable pressure drop in high dynamic steam supply. The verification method includes the following steps: S 9. By allowing the maximum pressure drop Δ P After confirming the flash evaporation process, the minimum pressure of steam generator 10 is... P 2. Among them, the maximum allowable pressure drop refers to the maximum pressure difference within the steam generator 10 under extreme operating conditions. This is the basis for achieving controllable pressure drop within the steam generator 10. △ P Satisfy the following formula: △P=P1 工作 -P 2 in, P1 工作 The steam generator 10 is in its initial state at the operating pressure.

[0044] S 10. Confirm the gas production rate of the flash process within the maximum allowable pressure drop range. x The core thermodynamic calculations for the flash evaporation process are as follows: Define the initial state, operating pressure of steam generator 10. P1 工作 In the middle, 1 kg The enthalpy of total saturated water is h 1.

[0045] The minimum pressure of steam generator 10 after the flash evaporation process P 2 in, 1 kg Total saturated water will separate into xkg Saturated steam and (1- x ) kg A two-phase mixture of saturated water xkg saturated vapor enthalpy value h 2″, (1- x ) kg Enthalpy of saturated water h 2.

[0046] Since flash evaporation is an adiabatic isenthalpic process, the total heat of the water remains constant before and after the pressure decreases. Therefore: initial total enthalpy = final total enthalpy, which can be expressed by the formula: h 1=x h 2 ″+(1-x) h 2 in, x The flash gas production rate refers to the per 1 kg Stored in P1 工作 Saturated water below, when the pressure drops P At 2 o'clock, there will be x The mass is instantly converted into steam.

[0047] S 11. Under extreme operating conditions of sudden changes in load demand, the total amount of steam that needs to be instantly replenished during the flash evaporation process. Ms This includes the following steps: S 110. When the load demand changes abruptly, the controller receives the response and... n The change in the opening degree of the proportional valve yields the steam flow gap Δ required at the load end under extreme operating conditions. Q , △ Q Satisfy the following formula: △ Q = Qmax - Qmin in, Qmax This represents the maximum steam demand required at the load end under extreme operating conditions. Qmin This represents the minimum steam requirement at the load end under extreme operating conditions.

[0048] S 111. Predetermined power lag time t Power lag time refers to the time it takes for the flash evaporation process to be covered.

[0049] S 113 . Calculate the total amount of steam Ms , Ms Satisfy the following formula: Ms =△ Q × t Among them, △ Q This represents the steam flow gap required at the load end under extreme operating conditions.

[0050] S 13. Based on total steam volume Ms Gas production rate during flash evaporation x Confirm the minimum liquid storage capacity of steam generator 10. m , minimum liquid storage volume m This refers to each 1 kgHydropower xkg Steam, so, to produce a total amount of steam... Ms The steam output must ensure that the minimum water volume within the steam generator 10 is greater than a certain amount. Specifically... m Satisfy the following formula: m = Ms / x In this embodiment, by clearly defining the maximum allowable pressure drop, the gas production rate of the flash evaporation process is calculated backwards. Then, the total amount of steam that the flash evaporation process needs to replenish instantaneously under extreme conditions of sudden changes in load demand is calculated. By using the gas production rate of the flash evaporation process and the total amount of steam required, the minimum liquid storage capacity is calculated. This minimum liquid storage capacity serves as an instantaneous energy reserve source, providing a material basis for replenishing steam when the load changes suddenly. This ensures that the reserve capacity can cover the steam demand gap during the heating lag period.

[0051] This embodiment mainly discloses three parts. The first part is the pressure reduction flash evaporation energy replenishment of the steam generator 10. It utilizes the physical property that the saturation temperature of water is positively correlated with the pressure. When the steam load suddenly changes and causes the outlet pressure of the steam generator 10 to drop, the high-temperature water stored in the steam generator 10 will have a higher actual temperature than the saturation temperature under the current pressure due to the sudden pressure drop, thereby rapidly vaporizing to generate steam and realizing the flash evaporation process. This process is fast and effective.

[0052] The second part focuses on rapid and precise steam supply during multi-loop high-dynamic load changes. The steam generator 10 is used for pressure reduction and flash evaporation to supplement energy during multi-loop load changes. Through the interaction of the controller and actuators, the steam supply is precisely maintained, preventing liquid carryover due to insufficient vaporization. The flash evaporation process instantly compensates for steam production gaps caused by heating lag, ensuring real-time matching of steam supply with load demand. This not only avoids insufficient vaporization due to untimely increases in heating power but also prevents unvaporized liquid water from entering subsequent pipelines with the steam, protecting the safety of load-side equipment and process stability. Furthermore, through closed-loop precise adjustment of heating power and the flash evaporation process, it avoids energy waste caused by overheating in traditional systems, saving energy and effectively preventing the risks of overheating and overpressure.

[0053] The third part is the volume optimization of the steam generator 10. That is, by clearly defining the maximum allowable pressure drop, the gas production rate of the flash process is back-calculated, and then the total amount of steam that the flash process needs to replenish instantaneously under extreme conditions of sudden changes in load demand is calculated. By calculating the gas production rate of the flash process and the total amount of steam required, the minimum liquid storage capacity is calculated. This minimum liquid storage capacity serves as an instantaneous energy reserve source, providing a material basis for steam replenishment when the load changes. It ensures that the reserve capacity can cover the steam demand gap during the heating lag period.

[0054] These three elements work in a progressive and interactive manner, enabling rapid and precise steam supply during sudden load changes. Furthermore, the flash-generated steam quickly fills the pressure gap caused by these load shifts, preventing a sharp drop in pressure in the steam generator 10 and maintaining the pressure at the pressure reducing valve inlet within a stable range. This ensures constant pressure at the valve's downstream end. By combining controllable pressure drop within the steam generator 10 with pressure reduction and flash-generated energy replenishment, the problems of pressure fluctuations at the pressure reducing valve outlet and deviations in the control reference of proportional valves and other regulating valves caused by sudden pressure drops in the steam generator 10, as seen in traditional technologies, are solved. This provides a stable pressure basis for precise flow regulation, achieving dual protection in both gas volume and pressure dimensions, effectively compensating for the lag between heating power adjustment and steam production increase.

[0055] Example 3 This embodiment, based on Embodiment 2, provides a specific application of the steam generator verification method, specifically as follows: First, the maximum allowable pressure drop Δ is selected. P It is 0.2 bar Initial state, steam generator 10 operating pressure P1 工作 7 bar The corresponding first water saturation temperature is T 1 is 164.97℃ .

[0056] Based on the formula: △P=P1 工作 -P 2. Obtain the initial state and operating pressure of steam generator 10. P 2 is 6.8 bar The corresponding second water saturation temperature is T 2 is 163.82℃.

[0057] Secondly, the operating pressure of steam generator 10 P1 工作 7 bar In the middle, 1 kg Enthalpy of total saturated water h 1 is 697. kJ / kg .

[0058] The minimum pressure of steam generator 10 after the flash evaporation process P 2 is 6.8 bar , xkg Enthalpy of saturated steam h 2 is 690.8 kJ / kg , xkg saturated vapor enthalpy h 2 ″ It is 2760.5 kJ / kg .

[0059] Based on the formula: h 1 =x h 2 ″+(1-x) h 2. The gas production rate of the flash evaporation process can be obtained. x It is 0.305%, which means that every 1 kg Stored in P1 工作 Saturated water below, when the pressure drops P At time 2, 0.305% of the mass will be instantly converted into steam.

[0060] Then, confirm the steam supply range and predict the maximum steam demand required at the load end under extreme operating conditions. Qmax 10 akg / min Minimum steam demand required by the load side before a sudden change in load demand. Qmin for akg / min .

[0061] Based on the formula: △ Q = Qmax - Qmin The steam flow gap Δ under extreme operating conditions was obtained. Q 9 akg / min .

[0062] Predetermined power lag time t 5 s The conversion unit is (5 / 60). min Based on the formula: Ms =△ Q × t The total amount of steam was obtained. Ms =(9 akg / min )×(5 / 60 min )=0.75 akg .

[0063] Finally, based on the formula: m = Ms / x ,calculate m It is 245.9 akg .

[0064] Example 4 See Figure 4 The difference between this embodiment and Embodiment 2 lies in two aspects: Difference 1: This embodiment provides a battery humidification system, which uses a steam flow control system to realize the activation test of the fuel cell, ensuring that the cathode and anode gases are supplied under a certain humidity.

[0065] Difference 2: The battery humidification system includes a steam flow control system, cathode circuit 2, anode circuit 3, fuel cell stack 4, cathode temperature control unit, anode temperature control unit, cathode exhaust unit 5, and anode exhaust unit 6. The steam flow control system removes the load end. Cathode circuit 2 is equipped with a cathode flow control unit and a cathode preheating unit. Cathode circuit 2 is used to input air, and the air flow is controlled by the cathode flow control unit. After the cathode preheating unit preheats the air, it is mixed with humidifying steam from the first branch. The cathode temperature control unit adjusts the temperature and humidity of the mixed gas to the target values ​​before it is introduced into the cathode inlet of fuel cell stack 4.

[0066] An anode flow control unit and an anode preheating unit are installed on the anode circuit 3. The anode circuit 3 is used to transport hydrogen. The hydrogen flow control unit controls the hydrogen flow rate. After the anode preheating unit preheats the hydrogen, it is mixed with humidifying steam from the second branch. The anode temperature control unit adjusts the temperature and humidity of the mixed gas to the target value before it is introduced into the anode inlet of the fuel cell stack 4.

[0067] The fuel cell stack 4 receives and processes the above-mentioned gases and carries out a chemical reaction. After the reaction, the cathode tail gas is processed by the cathode tail gas unit 5 and the anode tail gas is processed by the anode tail gas unit 6.

[0068] Difference 3: In the steam flow control system, controller 16 is replaced by control module 7. Control module 7 is electrically connected to anode flow control unit, cathode flow control unit, water supply pump 111, liquid level sensor 102, temperature sensor 105, pressure sensor 101, heating module 100, steam flow meter and proportional valve to form a closed-loop control.

[0069] In this embodiment, the steam generator 10 is integrated with pressure reduction flash evaporation for energy replenishment, rapid and precise steam supply under multi-loop high dynamic load changes, and volume optimization of the steam generator 10 into the battery humidification system. This addresses the problem of excessive dryness or wetness in the fuel cell stack 4 caused by insufficient response speed and stability in traditional control methods, particularly in high-dynamic scenarios such as fuel cell durability testing and multi-device batch testing. By achieving rapid steam response and precise steam supply, this embodiment ensures the long-term operational stability of the fuel cell stack 4 under high-dynamic conditions, overcoming the limitations of traditional methods that cannot meet the requirements of long-term dynamic testing or multi-device collaborative operation, thus restricting their application scope.

[0070] The stable operation process of this battery humidification system is as follows: S13. The battery humidification system initially idles, specifically including the following steps: S 130. The steam flow control system enters standby mode, meaning the load demand changes little. (See also...) S 1. No further explanation needed.

[0071] S 131. The cathode flow control unit controls the first flow of air to be input from the cathode circuit 2. After the air is preheated by the cathode preheating unit, it is mixed with the first flow of steam from the first branch. The cathode temperature control unit adjusts the temperature and humidity of the mixed gas to the target value before it is introduced into the cathode inlet of the fuel cell stack 4.

[0072] S 132. The anode flow control unit controls the first flow of hydrogen to be input from the anode circuit 3. After the hydrogen is preheated by the anode preheating unit, it is mixed with the first flow of steam from the second branch. The anode temperature control unit adjusts the temperature and humidity of the mixed gas to the target value before it is introduced into the anode inlet of the fuel cell stack 4.

[0073] S 133. The fuel cell stack 4 receives and processes the above-mentioned gas and carries out a chemical reaction. After the reaction, the cathode tail gas is processed by the cathode tail gas unit 5 and the anode tail gas is processed by the anode tail gas unit 6.

[0074] S 14. The high dynamic load response stage of the battery humidification system specifically includes the following steps: S 140. When the hydrogen flow rate input from anode circuit 3 and the air flow rate input from cathode circuit 2 rise to the second flow rate, the steam flow control system enters the second flow rate steam supply stage. (See reference...) S 2. This will not be elaborated further. The steam generator 10 flashes to quickly replenish the two steam circuits, avoiding steam supply delays that could lead to the fuel cell stack 4 becoming too dry.

[0075] S 141. The second flow of air is input from the cathode circuit 2. After the air is preheated by the cathode preheating unit, it is mixed with the second flow of steam from the first branch. The temperature and humidity of the mixed gas are adjusted to the target value by the cathode temperature control unit before being introduced into the cathode inlet of the fuel cell stack 4.

[0076] S 142. The second flow of hydrogen is input from the anode circuit 3. After the hydrogen is preheated by the anode preheating unit, it is mixed with the second flow of steam from the second branch. The temperature and humidity of the mixed gas are adjusted to the target value by the anode temperature control unit before being introduced into the anode inlet of the fuel cell stack 4.

[0077] S 143. The fuel cell stack 4 receives and processes the above-mentioned gas and carries out a chemical reaction. After the reaction, the cathode tail gas is processed by the cathode tail gas unit 5 and the anode tail gas is processed by the anode tail gas unit 6.

[0078] S 15. The stable operation phase of the battery humidification system under full load includes the following steps: S 150. The steam supply of the steam flow control system returns to stability. Specifically, the power of the heating module gradually catches up with the steam consumption, the flash effect weakens, and the steam pressure and output return to stability. (See reference...) S 3; Based on feedback from the liquid level sensor 102, the controller 16 starts the water replenishment pump 111 to perform closed-loop water replenishment in order to maintain a stable water level in the steam generator 10.

[0079] S 151. The anode circuit 3 and the cathode circuit 2 maintain a constant full-load gas flow rate and continuously supply the fuel cell stack 4. The fuel cell stack 4 operates at full load. The anode tail exhaust unit 6 and the cathode tail exhaust unit 5 work in coordination and maintain their respective circuit back pressure stability.

[0080] S 16. The load shedding phase of the battery humidification system specifically includes the following steps: S 160. As the hydrogen flow rate input from anode circuit 3 and the air flow rate input from cathode circuit 2 decrease, the steam flow control system enters the first flow rate steam supply stage. (See [reference]) S 4. This will not be elaborated further. Steam generation is suppressed by steam generator 10 to avoid the problem of excessive moisture in fuel cell stack 4.

[0081] S 161. The first flow of air is input from the cathode circuit 2. After the air is preheated by the cathode preheating unit, it is mixed with the first flow of steam from the first branch. The temperature and humidity of the mixed gas are adjusted to the target value by the cathode temperature control unit and then introduced into the cathode inlet of the fuel cell stack 4.

[0082] S 162. The first flow of hydrogen is input from the anode circuit 3. After the hydrogen is preheated by the anode preheating unit, it is mixed with the first flow of steam from the second branch. The temperature and humidity of the mixed gas are adjusted to the target value by the anode temperature control unit before being introduced into the anode inlet of the fuel cell stack 4.

[0083] S 163. The fuel cell stack 4 receives and processes the above-mentioned gas and carries out a chemical reaction. After the reaction, the cathode tail gas is processed by the cathode tail gas unit 5 and the anode tail gas is processed by the anode tail gas unit 6.

[0084] It is worth mentioning that the first flow rate and the second flow rate can be defined based on the actual operating conditions, with the first flow rate being less than the second flow rate.

[0085] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery humidification system, characterized in that, It includes a steam flow supply system, a cathode control loop, an anode control loop, an anode temperature control unit, a cathode temperature control unit, a fuel cell stack (4), a tailpipe unit, and a control module (7). The steam flow supply system is configured to supply steam to the fuel cell stack (4); the steam flow supply system includes a steam generator (10) and at least two steam control branches, the outlet of the steam generator (10) is connected to at least two steam control branches, one of which merges with the cathode control loop and is connected to the cathode inlet of the fuel cell stack (4) through the cathode temperature control unit; the other steam control branch merges with the anode control loop and is connected to the anode inlet of the fuel cell stack (4) through the anode temperature control unit; the outlet of the fuel cell stack (4) is connected to the tailpipe unit; The control module (7) is configured to trigger the flash process or suppress steam generation of the steam generator (10) based on the steam supply demand; the steam generator (10) is set to a minimum liquid storage capacity, which is set to the flash process, and the pressure drop in the steam generator (10) does not exceed the maximum allowable pressure drop.

2. The battery humidification system according to claim 1, characterized in that, An anode flow control unit and an anode preheating unit are installed on the anode control loop.

3. The battery humidification system according to claim 1, characterized in that, A cathode flow control unit and a cathode preheating unit are installed on the cathode control loop.

4. The battery humidification system according to claim 1, characterized in that, The steam generator (10) is equipped with a heating module (100) and a pressure sensing structure, with the heating module (100) located below the pressure sensing structure.

5. The battery humidification system according to claim 4, characterized in that, The steam generator (10) is also equipped with a baffle (103), and the heating module (100), pressure sensing structure and baffle (103) are arranged from bottom to top.

6. The battery humidification system according to claim 5, characterized in that, A demister (104) is also installed inside the steam generator (10), and the demister (104) is located above the baffle (103).

7. The battery humidification system according to claim 1, characterized in that, The steam flow supply system also includes a pressure reducing valve (13). The outlet of the steam generator (10) is connected to one end of the second pipeline. The pressure reducing valve (13) is installed on the second pipeline. The other end of the second pipeline is divided into two branches, which are connected to the steam control branch respectively. A steam flow meter and a proportional valve are installed in sequence on each of the steam control branches.

8. The battery humidification system according to claim 1, characterized in that, The steam flow supply system also includes a water supply module (11), which includes a water source supply (110), a water replenishment pump (111) and a check valve (113). The water source supply (110) is connected to the inlet of the steam generator (10) through a first pipeline, and the water replenishment pump (111) and the check valve (113) are installed in sequence on the first pipeline.

9. A method for verifying a steam generator (10) applied to a battery humidification system according to any one of claims 1 to 8, characterized in that, Includes the following steps: The minimum pressure of the steam generator (10) after confirming the flash process by allowing the maximum pressure drop; Confirm the gas production rate of the flash evaporation process within the maximum allowable pressure drop range; Confirm the total amount of steam that the flash process needs to replenish instantaneously under extreme operating conditions of sudden changes in steam supply demand; Based on the total steam volume and the gas production rate of the flash evaporation process, the minimum liquid storage capacity of the steam generator (10) is determined.

10. A battery humidification method using the battery humidification system according to any one of claims 1 to 8, characterized in that, Includes the following steps: When the hydrogen flow rate input to the anode circuit (3) and the air flow rate input to the cathode circuit (2) rise to the second flow rate, the control steam generator (10) triggers the flash evaporation process. One steam control branch merges with the cathode control circuit and is adjusted to the target temperature and humidity through the cathode temperature control unit before being introduced into the cathode inlet of the fuel cell stack (4). The other steam control branch merges with the anode control circuit and is adjusted to the target temperature and humidity through the anode temperature control unit before being introduced into the anode inlet of the fuel cell stack (4). The tail gas unit processes the exhaust gas. When the hydrogen flow rate input to the anode circuit (3) and the air flow rate input to the cathode circuit (2) decrease to the first flow rate, the steam generator (10) is controlled to suppress steam generation. One steam control branch merges with the cathode control circuit and is adjusted to the target temperature and humidity through the cathode temperature control unit before being introduced into the cathode inlet of the fuel cell stack (4). The other steam control branch merges with the anode control circuit and is adjusted to the target temperature and humidity through the anode temperature control unit before being introduced into the anode inlet of the fuel cell stack (4). The tail gas unit processes the exhaust gas.

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