A method for controlling the pulse emission of reactant gas during fuel cell start-up

Abstract

This application discloses a method for controlling pulsed emissions of reactant gas during fuel cell startup, relating to the field of fuel cells. The method includes: setting single-pulse emission parameters based on the capacity of the hydrogen removal reactor; establishing a dilution calculation model to predict changes in impurity concentration in the stack's gas chambers; determining, through iterative model calculations, the number of pulse emissions required to bring the impurity concentrations in the hydrogen and oxygen chambers below a threshold, and accordingly determining the total number of pulse emissions; and controlling the tailpipe valve to execute pulse emissions based on the total number of pulse emissions and the single-pulse parameters. This invention achieves on-demand emission through precise model calculations, significantly improving reactant gas utilization and reducing costs while ensuring safety and startup performance.

Description

Technical Field

[0001] This application relates to the field of fuel cells, and in particular to a method for controlling the pulse emission of reaction gas during the start-up process of a fuel cell. Background Technology

[0002] Before startup, hydrogen-oxygen fuel cells typically contain high concentrations of impurity gases (mainly nitrogen) in their internal gas chambers (anode and cathode) due to air intrusion during shutdown or protective nitrogen purging. To ensure the stack can generate electricity normally and efficiently, these impurity gases must be replaced and removed using high-purity reaction gases (hydrogen and air) during the startup phase.

[0003] Existing technologies typically employ a continuous tail-out displacement strategy, where the tail-out valve of the fuel cell stack is kept open for an extended period, allowing the reactant gas to continuously flow through and carry away impurity gases. This method relies heavily on operator experience for displacement time estimation, which has significant drawbacks: if the displacement time is set too long, a large amount of unreacted hydrogen will be directly emitted, resulting in severe fuel waste and reduced overall system economy. More seriously, the instantaneous large flow of hydrogen emitted may exceed the catalytic processing capacity of the downstream hydrogen removal reactor, causing untreated hydrogen to be released directly into the environment. Accumulation in enclosed or semi-enclosed spaces can easily trigger hydrogen concentration alarms or even detonation accidents, posing serious safety hazards. Conversely, if the displacement time is set too short, impurity gases in the gas chamber cannot be fully replaced, leading to a decrease in the partial pressure of the reactant gas, which in turn affects the output performance of the fuel cell stack and may even cause start-up failure.

[0004] To address these issues, some improvements employ pulsed emissions or incorporate mass flow controllers and buffer tanks into the tailpipeline. These measures, by limiting instantaneous emission flow rates to match the processing capacity of the hydrogen removal reactor, improve safety to some extent. However, these methods are essentially still open-loop or based on simple feedback control, failing to solve the core efficiency problem. They cannot accurately determine the total emission amount based on actual changes in impurity concentration within the fuel cell stack; the number of emissions and the amount emitted per emission still rely on empirical settings. This makes it difficult to effectively reduce the total amount of reactant gas emissions while ensuring that impurities are adequately replaced to the target concentration. Therefore, the problem of low reactant gas utilization remains prominent. Summary of the Invention

[0005] The purpose of this application is to provide a method for controlling the pulse emission of reactant gas during the start-up process of a fuel cell, which aims to solve the problem that in existing fuel cell start-up replacement technologies, it is difficult to accurately control the emission of reactant gas while ensuring safety and start-up performance, resulting in low utilization of reactant gas.

[0006] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides a method for controlling the pulse emission of reactant gas during the start-up process of a fuel cell, comprising: Based on the hydrogen removal capacity and volume of the hydrogen removal reactor equipped in the fuel cell system, the gas volume, valve closing time, and valve opening time for a single pulse emission of the hydrogen chamber and oxygen chamber of the fuel cell stack are set. Based on the gas volume of a single pulse emission and the real-time state parameters of the fuel cell stack gas chamber, a dilution calculation model is established to predict the changes in impurity gas concentration in the hydrogen chamber and the oxygen chamber, respectively. According to the dilution calculation model, iterative calculations are performed by continuously increasing the number of pulse emissions to obtain the impurity gas concentrations in the hydrogen chamber and the oxygen chamber after each pulse emission. The number of pulse emissions when the concentration of impurity gas in the hydrogen chamber and the oxygen chamber first falls below or equals a preset threshold is determined respectively; The total number of pulse emissions is determined based on the number of pulse emissions from the hydrogen chamber and the number of pulse emissions from the oxygen chamber; The tail valve of the fuel cell stack is controlled to perform pulse emission operation based on the total number of pulse emissions and the valve opening and closing time of a single pulse emission.

[0007] Secondly, this application provides a fuel cell system, comprising: The fuel cell stack has a hydrogen chamber and an oxygen chamber; A tail discharge valve is installed at the tail discharge port of the fuel cell stack; A hydrogen removal reactor is installed at the rear end of the tail valve; And a controller electrically connected to the tailpipe valve; The controller is configured to perform a reaction gas pulse emission control method for the fuel cell startup process as described in the first aspect.

[0008] Thirdly, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the reaction gas pulse emission control method for the fuel cell start-up process described in any one of the above.

[0009] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the reaction gas pulse emission control method for the fuel cell start-up process described above.

[0010] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the reaction gas pulse emission control method for the fuel cell start-up process described above.

[0011] According to the specific embodiments provided in this application, the following technical effects are disclosed: 1. Improved reactant gas utilization and reduced operating costs: This invention establishes a dilution calculation model and iteratively calculates the minimum number of pulses required to reach the target impurity concentration, avoiding the problem of excessive reactant gas emissions caused by relying on empirical estimations in existing technologies. This precise "on-demand emission" control method can maximize the conservation of fuels such as hydrogen while ensuring the replacement effect, significantly improving the system's economic efficiency.

[0012] 2. Enhanced safety during startup: This invention first sets the gas volume and valve closing time for a single pulse emission based on the actual hydrogen removal capacity and volume of the hydrogen removal reactor, ensuring that the amount of hydrogen emitted in a single pulse and its processing time are both within safe thresholds. This fundamentally avoids the risk of hydrogen accumulation and detonation that may be caused by excessive instantaneous emission flow exceeding the hydrogen removal capacity.

[0013] 3. Ensuring startup performance and reliability: By accurately calculating and determining the number of pulses required for the hydrogen chamber and oxygen chamber respectively through the model, it is ensured that the impurity gases on both sides of the fuel cell stack can be fully replaced to below the preset threshold that does not affect the performance of the fuel cell stack, thereby ensuring the output performance of the fuel cell stack and the success rate and consistency of each startup. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic flowchart of a reaction gas pulse emission control method for the fuel cell start-up process in one embodiment of this application; Figure 2 This is a schematic diagram of the architecture of a fuel cell system in one embodiment of this application. Detailed Implementation

[0016] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] The reaction gas pulse emission control method for the fuel cell start-up process in this embodiment is executed by a computer device, which can be a terminal computing device or a server. The terminal computing device can be, but is not limited to, various desktop computers, laptops, smartphones, tablets, IoT devices, etc. The server can be a standalone server or a server cluster composed of multiple servers, or it can be a cloud server.

[0019] This application provides a method for controlling the pulse emission of reactant gas during the fuel cell startup process. It aims to address the problem in existing fuel cell startup replacement technologies where it is difficult to precisely control the emission of reactant gas while ensuring safety and startup performance, resulting in low reactant gas utilization. The core idea of ​​this method is to abandon the traditional experience-based open-loop emission strategy and instead adopt a closed-loop control strategy based on precise calculations using a theoretical model to achieve "on-demand emission," thereby maximizing reactant gas utilization while ensuring safety and performance.

[0020] In one embodiment of this application, the method for controlling the pulse emission of reactant gas during the fuel cell start-up process specifically includes: Step S110: Based on the hydrogen removal capacity and volume of the hydrogen removal reactor equipped in the fuel cell system, set the gas volume, valve closing time, and valve opening time for a single pulse emission of the hydrogen chamber and oxygen chamber of the fuel cell stack.

[0021] Step S120: Based on the gas volume of a single pulse emission and the real-time state parameters of the fuel cell stack, establish a dilution calculation model for predicting the changes in impurity gas concentrations in the hydrogen chamber and oxygen chamber, respectively.

[0022] Step S130: Based on the dilution calculation model, iterative calculation is performed with the number of pulse emissions continuously increasing as the iterative action to obtain the impurity gas concentration in the hydrogen chamber and oxygen chamber after each pulse emission.

[0023] Step S140: Determine the number of pulse emissions when the concentration of impurity gas in the hydrogen chamber and oxygen chamber first falls below or equals a preset threshold.

[0024] Step S150: Determine the total number of pulse emissions based on the number of pulse emissions from the hydrogen chamber and the number of pulse emissions from the oxygen chamber.

[0025] Step S160: Based on the total number of pulse emissions and the valve opening and closing time of a single pulse emission, control the tail valve of the fuel cell stack to perform pulse emission operation.

[0026] Specifically, regarding the above technical solution: The overall logic is to first analyze the system's safety boundaries to determine the upper limit of a single emission operation. This is based on the hydrogen removal capacity and volume of the hydrogen removal reactor equipped in the fuel cell system, to set the gas volume, valve closing time, and valve opening time for a single pulse emission into the hydrogen and oxygen chambers of the fuel cell stack. This step fundamentally ensures that no emission event will threaten system safety. Its design aims to strictly control the instantaneous hydrogen emission rate within the processing capacity of the hydrogen removal reactor, resolving the safety hazard of hydrogen accumulation caused by continuous or excessive emissions in the background technology. Pre-setting a safe single emission amount lays the foundation for subsequent precise control.

[0027] After determining the safe operating parameters for a single emission, this scheme further establishes a mathematical model to predict the emission process. Specifically, based on the gas volume of a single pulse emission set in the previous step and the real-time state parameters of the fuel cell stack gas chamber obtained from the system, a dilution calculation model is established to predict the changes in impurity gas concentrations in the hydrogen and oxygen chambers, respectively. This model is the core of achieving precise control, as it links macroscopic emission actions with microscopic concentration changes, making the previously invisible impurity concentration change process calculable and predictable. In this way, the problem of traditional methods being unable to grasp the gas state inside the chamber in real time is solved, realizing the transformation from "blind emission" to "transparent emission."

[0028] Once the model is established, it can be used for extrapolation calculations. This method involves iterative calculations based on a dilution calculation model, using an increasing number of pulse emissions as the iteration action, to obtain the impurity gas concentrations in the hydrogen and oxygen chambers after each pulse emission. This step is essentially a simulation process; before any actual emission operation is performed, the controller internally "pre-simulates" the entire replacement process, calculating the decay curve of the impurity concentration after each pulse. This predictive calculation allows the control strategy to be formulated no longer based on lagging sensor feedback, but rather on forward-looking model predictions, greatly improving the accuracy and response speed of the control.

[0029] After obtaining predicted data on the change in impurity gas concentration with the number of pulse emissions, the next step is to determine the replacement endpoint. This method determines the number of pulse emissions required for the impurity gas concentration in the hydrogen and oxygen chambers to first fall below or equal to a preset threshold. The preset threshold is set based on the performance requirements for the fuel cell stack to enter normal power generation, ensuring sufficient replacement. By comparing the iteratively calculated concentration values ​​with this threshold one by one, the minimum number of pulses required to meet the conditions can be accurately found, thus solving the problems of performance degradation due to insufficient replacement or fuel waste due to excessive replacement in traditional methods.

[0030] Because the hydrogen chamber and oxygen chamber may have different volumes, operating pressures, and initial impurity conditions, the required number of pulse emissions may also differ. Therefore, this method further includes determining a unified total number of pulse emissions based on the number of pulse emissions from the hydrogen chamber and the oxygen chamber. This step reflects a holistic consideration of the entire fuel cell stack system's state, ensuring that both sides reach optimal startup conditions and avoiding poor overall system performance caused by premature termination of emissions due to one side meeting the conditions.

[0031] Finally, after all calculations and decisions are completed, the controller translates the theoretical calculations into actual physical operations. This method involves controlling the stack's tail valves (such as hydrogen and oxygen tail valves) to perform pulse emission operations based on the determined total number of pulse emissions and preset valve opening and closing times for each pulse emission. Through this series of interconnected steps, this method guides actual physical operations with precise theoretical calculations, achieving refined management of gas emissions throughout the entire start-up and replacement process, thus achieving a balance between safety, performance, and economy.

[0032] Therefore, this application can precisely control the emission of reactant gas while ensuring safety and start-up performance. It solves the problem in existing fuel cell start-up replacement technology that it is difficult to precisely control the emission of reactant gas while ensuring safety and start-up performance, resulting in low utilization of reactant gas.

[0033] In one specific embodiment, the real-time status parameters of the fuel cell stack include at least the pressures in the hydrogen and oxygen chambers before startup. ,temperature and volume fuel cell stack operating pressure and fuel cell operating temperature and the purity of the reactant gases used. .

[0034] These parameters collectively constitute a "snapshot" describing the system's initial state and operating boundaries, forming the cornerstone of dilution calculation models. For example, the pressure and temperature before startup determine the initial molar amount of impurity gas, while the operating pressure and temperature affect the gas density and volume during the displacement process, and the purity of the reactant gas relates to the new impurities introduced during replenishment. By accurately obtaining these parameters, dilution calculation models can more realistically reflect physical reality, thereby improving the accuracy of predictions.

[0035] In one specific implementation, the dilution calculation model is constructed based on the ideal gas law, and during iterative calculation, the amount of impurity gas carried away by the gas discharged in a single pulse emission and the amount of impurity gas introduced by the newly replenished reaction gas are taken into account.

[0036] The ideal gas law is a fundamental physical law describing gas behavior, providing a solid theoretical foundation for dilution calculation models. Simultaneously, by accurately considering the "expenditure" (exhausted with the exhaust gas) and "intake" (carried in with the fresh gas) of impurities, a dynamic equilibrium equation for impurities is constructed. This allows the dilution calculation model to accurately track the impact of each pulse operation on the total amount of impurities, which is key to achieving accurate iterative calculations.

[0037] The following provides an example of constructing a dilution calculation model. The fuel cell stack gas chamber is divided into a hydrogen chamber and an oxygen chamber, and the modeling process for the dilution calculation model is the same for both chambers. In the following modeling example, if the dilution calculation model is used to calculate the impurity gas concentration in the hydrogen chamber, then the term "gas chamber" refers to the hydrogen chamber; if the dilution calculation model is used to calculate the impurity gas concentration in the oxygen chamber, then the term "gas chamber" refers to the oxygen chamber.

[0038] 1. Calculate the volume of impurity gas in the fuel cell stack gas chamber under standard conditions before startup. The formula is: in, The pressure inside the air chamber before startup is equal to atmospheric pressure, 101.3125 kPa. The volume of the pre-start air chamber, in liters (L). This refers to the temperature inside the gas chamber before startup; here it is the temperature of the fuel cell stack, in °C. The gas pressure under standard conditions is 101.3125 kPa; The volume of impurity gas under standard conditions is uniformly converted to the unit L; The gas temperature is 0℃ under standard conditions; the gas in the gas chamber before startup is nitrogen, which is an impurity gas. The volume of the impurity gas under standard conditions before startup can be calculated using the above formula. .

[0039] 2. Calculate the volume of gas in the gas chamber under standard conditions after the reactant gas enters the gas chamber during startup. The formula is: in, This is the pressure of the reaction gas at startup, which here is the stack operating pressure, in kPa. This represents the volume of the reacting gas at startup; here it refers to the volume of the gas chamber, in liters (L). This refers to the temperature of the reaction gas at startup, which is the operating temperature of the fuel cell stack, in °C. The gas pressure under standard conditions is 101.3125 kPa; The volume of gas in the gas chamber under standard conditions is uniformly converted to the unit L; The gas temperature under standard conditions is 0℃.

[0040] 3. Calculate the initial volume concentration of the impurity gas. The formula is: 4. Calculate the volume of the gas mixture in a single pulse emission under standard conditions. The formula is: in, The pressure of the gas emitted in a single pulse is equal to atmospheric pressure, which is 101.3125 kPa. The volume of gas emitted in a single pulse, in liters (L). The temperature of the gas emitted in a single pulse is the ambient temperature, in °C. The pressure of the gas under standard conditions is 101.3125 kPa.

[0041] 5. Calculate the volume concentration of the remaining impurity gas in the gas chamber after the Nth pulse emission. The formula is: in, Let N be the amount of impurity gas emitted in the Nth pulse, and , This refers to the amount of impurity gas introduced by the additional reactant gas after each pulse emission, and , The purity of the reactant gas.

[0042] The above, The calculation formula is a dilution calculation model, which can be used to iteratively calculate the concentration of impurity gas after each pulse emission. For example: Initial volume concentration of impurity gases before the first pulse emission .

[0043] During the first pulse emission, the volume of the discharged mixed gas is The amount of impurity gas it contains .

[0044] After the pulse emission ends, the intake valve replenishes fresh reactant gas to maintain the chamber pressure. The volume of this newly replenished reactant gas is also [missing information]. The amount of impurity gas it contains , The purity of the reactant gas is given; for example, if the hydrogen purity is 99.97%, the impurity content is 0.03%. Therefore, after the first pulse emission, the total amount of impurity gas remaining in the gas chamber is: After venting and replenishing air, the pressure in the air chamber returns to the working pressure, and the remaining total volume remains the same. Therefore, the concentration of impurity gases after the first pulse emission... for: .

[0045] And so on, the concentration of impurity gases after the Nth pulse emission... The general formula is: .

[0046] Among them, the amount of impurity gas emitted by the nth pulse emission That is, it depends on the concentration after the last emission.

[0047] Based on the impurity gas volume concentration value (preset threshold) set when the fuel cell stack transitions from startup to operation, the following can be obtained: The maximum allowed value. For example, when the hydrogen purity requirement is 99.97%, here... It should be 0.03%. The specific value of the preset threshold should be determined based on the actual performance parameters of the fuel cell stack used.

[0048] In one specific embodiment, the total number of pulse emissions is determined based on the number of pulse emissions from the hydrogen chamber and the number of pulse emissions from the oxygen chamber. Specifically, this includes taking the larger of the number of pulse emissions from the hydrogen chamber and the number of pulse emissions from the oxygen chamber as the total number of pulse emissions.

[0049] This "take the larger value" strategy is a conservative and reliable engineering choice designed to ensure sufficient gas replacement on both sides of the fuel cell stack (anode and cathode). This is because if the impurity concentration on either side is substandard, the overall performance of the stack will be limited. By performing the larger of the two replacement cycles, the preset purity requirements can be met even on the side requiring more replacement cycles, thus ensuring a smooth and efficient startup of the entire fuel cell stack as a whole.

[0050] In one alternative implementation, the execution method for the total number of pulse emissions can be further optimized. If the number of pulse emissions N1 required for the hydrogen chamber is greater than the number of pulse emissions N2 required for the oxygen chamber, then N2 pulse emissions can be performed simultaneously on both the hydrogen and oxygen chambers first; then, the pulse emission operation of the oxygen chamber is stopped, and only the (N1-N2) pulse emission operation continues to be performed on the hydrogen chamber. This asymmetric coordinated emission strategy, compared to the simple strategy of performing N1 pulses on both sides, has the technical advantage of significantly improving the utilization rate of the reactant gases, especially when the difference between N1 and N2 is large. By stopping the emission of the oxygen chamber in a timely manner after the oxygen chamber has been replaced, unnecessary consumption of air (as an oxygen source) is avoided, achieving extreme economy and reducing operating costs while ensuring start-up performance.

[0051] Exemplarily, after the controller calculates the required number of times N1 (e.g., 3 times) for the hydrogen chamber and the required number of times N2 (e.g., 2 times) for the oxygen chamber, it does not directly let both sides execute 3 pulses. Instead, a two-stage refined control strategy is adopted. In the first stage, the controller controls the hydrogen tail gas discharge valve and the oxygen tail gas discharge valve to synchronously execute 2 pulse discharge operations. In the second stage, that is, after the first 2 pulse discharges are completed, since the replacement task of the oxygen chamber has been completed, the controller stops operating the oxygen tail gas discharge valve and keeps it closed. For the hydrogen chamber that still needs to be replaced, the controller then continues to separately control the hydrogen tail gas discharge valve to execute 1 pulse discharge operation. In this way, unnecessary discharge of the oxygen chamber (air) in the second half is avoided. Compared with the scheme of executing 3 pulses on both sides, the air consumption of 1 pulse cycle is saved, thereby further improving the gas utilization rate and reducing the operating cost without sacrificing any performance and safety.

[0052] In a specific embodiment, the steps of setting the gas volume of a single pulse discharge include: setting the gas volume b of a single pulse discharge of the hydrogen chamber; wherein, the gas volume b is less than the volume B of the hydrogen elimination reactor; setting the gas volume c of a single pulse discharge of the oxygen chamber; wherein, the gas volume c is half of the gas volume b.

[0053] b being less than B is the core safety constraint, ensuring that the hydrogen discharged in a single emission can be completely accommodated and processed by the hydrogen elimination reactor. And c = b / 2 is considered based on the stoichiometric ratio of hydrogen-oxygen electrochemical reaction (2:1), making the replacement of oxygen match the replacement of hydrogen in a chemical sense, which helps to achieve a balanced startup process.

[0054] Preferably, the gas volume b is equal to half of the volume B of the hydrogen elimination reactor. Setting b as B / 2 provides a clear and preferably value with a large safety margin on the premise of meeting the safety constraint (b < B). This setting achieves a good balance between safety and replacement efficiency, ensuring extremely high safety and avoiding the problem of excessive pulse times and too long startup time due to too small b value.

[0055] In a specific embodiment, the steps of setting the valve closing time and valve opening time of a single pulse discharge include: setting the valve closing time T1 of a single pulse discharge of the hydrogen chamber and the oxygen chamber according to the hydrogen elimination capacity a of the hydrogen elimination reactor and the gas volume b; wherein, T1 = (b × 60) / a; determining the valve opening time T2 of a single pulse discharge of the hydrogen chamber according to the gas volume b, the stack working pressure of the hydrogen chamber, and the tail gas pipeline flow rate; determining the valve opening time T3 of a single pulse discharge of the oxygen chamber according to the gas volume c and the tail gas pipeline flow rate of the oxygen chamber.

[0056] In summary, the opening and closing cycle of the tail gas discharge valve of the hydrogen chamber is The opening and closing cycle of the oxygen chamber's exhaust valve is... The shortest startup time for the fuel cell module is... ,in, for and The larger of the two values, where N is the total number of pulse emissions.

[0057] The valve closing time T1 is designed to provide the hydrogen removal reactor with sufficient reaction time to process the hydrogen emitted in the previous pulse. Its calculation formula directly links the emission volume and processing capacity, and is the core algorithm for achieving safe control. The valve opening times T2 and T3, based on fluid dynamics principles, are the times required to accurately discharge the target volumes b and c, ensuring the consistency between the input (single emission gas volume) calculated by the model and the actual execution results.

[0058] For example, the steps of setting the valve closing time and valve opening time for a single pulse emission include: S11: Obtain the key parameters of the hydrogen removal reactor: hydrogen removal capacity of aL / min, volume of BL, and then set the mixed gas volume of a single pulse emission from the hydrogen chamber to bL; wherein the mixed gas includes hydrogen and nitrogen. To ensure safety, the mixed gas volume b of a single pulse emission from the hydrogen chamber is smaller than the hydrogen removal reactor container B. Preferably, b = B / 2 to ensure sufficient safety margin.

[0059] S12: Based on the hydrogen removal capacity aL / min and the mixed gas volume b of a single pulse emission from the hydrogen chamber, the single pulse valve closing time on the oxygen side can be calculated. The calculation formula is as follows: For 10 seconds, the tail valve remains closed, allowing sufficient time for the oxygen in the hydrogen removal reactor to fully react with the hydrogen.

[0060] S13: Based on the set mixed gas volume b of a single pulse emission from the hydrogen chamber, the current working pressure of the fuel cell hydrogen chamber, and the flow characteristics of the tailpipe (such as pipe diameter, length, and flow coefficient of the tailpipe valve), the valve opening time required to discharge bL gas can be determined through experiments or theoretical calculations, i.e., the single pulse valve opening time of the hydrogen chamber. .

[0061] S14: For the oxygen chamber, based on the stoichiometric ratio of the chemical reaction. To match the hydrogen chamber emission, the mixed gas volume for a single pulse emission of the oxygen chamber is typically set to c = b / 2. Similarly, based on the c value, the operating pressure of the fuel cell stack's oxygen chamber, and the flow rate in the tailpipe, the single pulse valve opening time of the oxygen chamber can be determined. The valve closing time of the oxygen chamber is consistent with that of the hydrogen chamber, which is also for... This is to ensure system synchronization.

[0062] It should be noted that the dilution calculation model given above is as follows: When used to calculate the concentration of impurity gases in the hydrogen chamber, among which... Let b be the gas volume. When using this to calculate the concentration of impurity gases in the hydrogen chamber, [the following is a partial translation of the original text, which is incomplete and requires further context]. Let c be the volume of the gas.

[0063] In an optional implementation, to enhance the system's environmental adaptability, the pre-set steps may further include acquiring the current ambient temperature; determining the actual hydrogen removal capacity of the hydrogen removal reactor at the current temperature based on the ambient temperature and a pre-stored relationship between the efficiency of the hydrogen removal reactor and temperature; and dynamically adjusting the gas volume emitted in a single pulse or the valve closing time of a single pulse based on the actual hydrogen removal capacity. Since the catalytic activity of the hydrogen removal reactor is temperature-sensitive, this measure, by introducing temperature compensation, allows the control strategy to adapt to different operating environments (such as cold winter regions or hot summer regions), always maintaining optimal safety and efficiency, significantly improving the system's robustness and reliability.

[0064] In another alternative implementation, to address the discrepancy between the ideal model and complex physical realities, the dilution calculation model may include an adjustable correction coefficient. The method also includes comparing the model-predicted impurity gas concentration with the actual impurity gas concentration obtained through sensor measurements or performance back-calculation after a pulse emission operation; and adjusting the correction coefficient based on the deviation in the comparison results to improve the accuracy of model predictions during subsequent startups. This adaptive learning and calibration mechanism, by introducing closed-loop feedback, enables the model to continuously self-optimize and self-improve during use, compensating for model mismatch issues caused by factors such as fuel cell aging and manufacturing tolerances, thereby ensuring high-precision control and efficient operation of the system throughout its entire lifecycle.

[0065] As can be seen from the above embodiments, the reaction gas pulse emission control method for the fuel cell start-up process in this application has the following technical effects: Based on the hydrogen removal capacity and volume parameters of the hydrogen removal reactor, the gas volume, valve opening time, and valve closing time for a single pulse emission are set to achieve precise control of the emission flow rate. This ensures that the instantaneous emission flow rate does not exceed the processing limit of the hydrogen removal reactor, fundamentally avoiding the safety risks caused by excessive instantaneous hydrogen emission. Simultaneously, this scheme designs an impurity gas dilution calculation model. Based on the real-time state parameters of the fuel cell stack's gas chamber and combined with the gas volume of a single pulse emission, it can dynamically calculate the impurity gas concentration in the fuel cell stack's gas chamber after each pulse emission. Through iterative calculation, when the model predicts that the impurity gas concentration is lower than a preset threshold, the required total number of pulse emissions can be determined. After determining the total number of pulse emissions, pulse emission operations are performed on the fuel cell stack according to the determined total number of pulses. This ensures that the total emission of reactant gas is precisely controlled while ensuring sufficient replacement of impurity gas, avoiding the fuel waste problems caused by traditional continuous emission or empirical pulse emission. It solves the problem of accurately controlling the number of emissions in existing technologies. Compared with solutions that rely solely on experience to set emission times or simply limit flow, it can adaptively terminate the emission process based on real-time changes in impurity concentration, effectively avoiding excessive waste of reaction gas due to excessive emissions.

[0066] In one embodiment of this application, a fuel cell system is also provided, which serves as the physical embodiment of the aforementioned method. The system includes a fuel cell stack 1 having a hydrogen chamber and an oxygen chamber; tailpipe valves, such as a hydrogen tailpipe valve 9 and an oxygen tailpipe valve 11, disposed at the tailpipe outlet of the stack 1; a hydrogen removal reactor 2 disposed downstream of the tailpipe valves; and a controller electrically connected to the tailpipe valves. The core feature of this controller is that it is configured to execute any of the reaction gas pulse emission control methods described above for the fuel cell start-up process. This means that the controller internally incorporates the corresponding algorithms and logic, enabling a series of operations such as parameter setting, model building, iterative calculation, number of iterations, and pulse execution, thereby materializing the abstract control method into a functional hardware entity.

[0067] In one specific embodiment, the fuel cell system includes a fuel cell stack 1, a hydrogen removal reactor 2, an inlet valve, an exhaust valve, and a controller. The fuel cell stack 1 has a hydrogen chamber and an oxygen chamber. The inlet valve includes a hydrogen solenoid valve 3 and an oxygen solenoid valve 6, and the exhaust valve includes a hydrogen exhaust valve 9 and an oxygen exhaust valve 11. Further, the system also includes a hydrogen proportioning valve 4, an oxygen proportioning valve 7, a hydrogen ejector 5, an oxygen ejector 8, a hydrogen flame arrester 10, an oxygen flame arrester 12, a three-way connector 13, a one-way valve 14, and an air pump 15. Specifically, the hydrogen source is connected to the hydrogen chamber inlet of the fuel cell stack 1 in sequence via the hydrogen solenoid valve 3, the hydrogen proportioning valve 4, and the hydrogen ejector 5, and the oxygen source is connected to the oxygen chamber inlet of the fuel cell stack 1 in sequence via the oxygen solenoid valve 6, the oxygen proportioning valve 7, and the oxygen ejector 8. The solenoid valves are used to control the flow of the reactant gas, the proportioning valves are used to regulate the flow rate of the reactant gas entering the fuel cell stack 1, and the ejector vessels are used to uniformly mix and distribute the reactant gas. The hydrogen outlet of fuel cell stack 1 is connected to hydrogen elimination reactor 2 via hydrogen exhaust valve 9 and hydrogen flame arrester 10. The oxygen outlet of fuel cell stack 1 is connected to one end of a three-way connector 13 via oxygen exhaust valve 11 and oxygen flame arrester 12. The other end of the three-way connector 13 is connected to the outlet of air pump 15 via a one-way valve 14. The inlet of air pump 15 is open to the atmosphere and is used to supplement air to hydrogen elimination reactor 2 to promote the full reaction of hydrogen and oxygen. The common end of the three-way connector 13 is connected to hydrogen elimination reactor 2. The exhaust valve is used to control the discharge of reaction gas from fuel cell stack 1, the flame arrester prevents backfire, and the hydrogen elimination reactor 2 is used to safely treat the hydrogen in the exhaust gas. The controller is electrically connected to the hydrogen solenoid valve 3, oxygen solenoid valve 6, hydrogen proportional valve 4, oxygen proportional valve 7, hydrogen tail exhaust valve 9, oxygen tail exhaust valve 11, and air pump 15, respectively. It is used to receive real-time status parameters of the fuel cell stack 1 from relevant pressure sensors, temperature sensors, etc., according to preset control logic or program, and execute the reaction gas pulse emission control method of the fuel cell start-up process as described in the first aspect, so as to control the opening and closing of each valve, the opening degree of the proportional valve, and the start and stop of the air pump 15, so as to realize the pulse emission control of the reaction gas on the hydrogen side and oxygen side of the fuel cell stack 1, and ensure that the fuel cell stack 1 completes the replacement of impurity gases efficiently and safely during the start-up phase.

[0068] In one exemplary embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0069] In one exemplary embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0070] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0071] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0072] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0073] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0074] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for controlling the pulse emission of reactant gas during the start-up process of a fuel cell, characterized in that, include: Based on the hydrogen removal capacity and volume of the hydrogen removal reactor equipped in the fuel cell system, the gas volume, valve closing time and valve opening time for a single pulse emission of the hydrogen chamber and oxygen chamber of the fuel cell stack are set. Based on the gas volume of a single pulse emission and the real-time state parameters of the fuel cell stack, a dilution calculation model is established to predict the changes in impurity gas concentrations in the hydrogen chamber and the oxygen chamber, respectively. According to the dilution calculation model, iterative calculations are performed by continuously increasing the number of pulse emissions to obtain the impurity gas concentrations in the hydrogen chamber and the oxygen chamber after each pulse emission. The number of pulse emissions when the concentration of impurity gas in the hydrogen chamber and the oxygen chamber first falls below or equals a preset threshold is determined respectively; The total number of pulse emissions is determined based on the number of pulse emissions from the hydrogen chamber and the number of pulse emissions from the oxygen chamber; The tail valve of the fuel cell stack is controlled to perform pulse emission operation based on the total number of pulse emissions and the valve opening and closing time of a single pulse emission.

2. The method for controlling the pulse emission of reactant gas during the start-up process of a fuel cell according to claim 1, characterized in that, The real-time status parameters of the fuel cell stack include at least: The pressure, temperature, and volume of the hydrogen chamber and the oxygen chamber before startup; The operating pressure and temperature of the fuel cell stack, as well as the purity of the reaction gas used.

3. The method for controlling the pulse emission of reactant gas during fuel cell start-up according to claim 1, characterized in that, The dilution calculation model is based on the ideal gas law and, during iterative calculation, considers the amount of impurity gas carried away by the gas emitted in a single pulse emission and the amount of impurity gas introduced by the newly added reaction gas.

4. The method for controlling the pulse emission of reactant gas during the fuel cell start-up process according to claim 1, characterized in that, The total number of pulse emissions is determined based on the number of pulse emissions from the hydrogen chamber and the number of pulse emissions from the oxygen chamber, specifically including: The larger of the number of pulse emissions from the hydrogen chamber and the number of pulse emissions from the oxygen chamber is taken as the total number of pulse emissions.

5. The method for controlling the pulse emission of reactant gas during fuel cell start-up according to claim 1, characterized in that, The method for executing the total number of pulse emissions is as follows: If the number of pulse emissions N1 required for the hydrogen chamber is greater than the number of pulse emissions N2 required for the oxygen chamber, then N2 pulse emission operations are performed synchronously on the hydrogen chamber and the oxygen chamber first; then, the pulse emission operation of the oxygen chamber is stopped, and only the N1-N2 pulse emission operation is performed on the hydrogen chamber.

6. The method for controlling the pulse emission of reactant gas during the start-up process of a fuel cell according to claim 1, characterized in that, The step of setting the gas volume for a single pulse emission includes: The gas volume b of a single pulse emission from the hydrogen chamber is set; wherein the gas volume b is less than the volume B of the hydrogen elimination reactor; The gas volume c of a single pulse emission from the oxygen chamber is set; wherein the gas volume c is half of the gas volume b.

7. The method for controlling the pulse emission of reactant gas during the fuel cell start-up process according to claim 6, characterized in that, The gas volume b is equal to half the volume B of the hydrogen removal reactor.

8. The method for controlling the pulse emission of reactant gas during the start-up process of a fuel cell according to claim 6 or 7, characterized in that, The steps for setting the valve closing time and valve opening time for a single pulse emission include: Based on the hydrogen removal capacity 'a' of the hydrogen removal reactor and the gas volume 'b', the valve closing time T1 for a single pulse emission of the hydrogen chamber and the oxygen chamber is set; where T1 = (b 60) / a; The valve opening time T2 for a single pulse emission of the hydrogen chamber is determined based on the gas volume b, the working pressure of the fuel cell in the hydrogen chamber, and the flow rate of the tailpipe. The valve opening time T3 for a single pulse emission of the oxygen chamber is determined based on the gas volume c and the flow rate of the tailpipe of the oxygen chamber.

9. The method for controlling the pulse emission of reactant gas during fuel cell start-up according to claim 1, characterized in that, Also includes: Get the current ambient temperature; Based on the ambient temperature and the pre-existing relationship between the efficiency of the hydrogen removal reactor and temperature, determine the actual hydrogen removal capacity of the hydrogen removal reactor at the current temperature; Based on the actual hydrogen elimination capacity, the gas volume emitted in a single pulse or the valve closing time of a single pulse is dynamically adjusted.

10. The method for controlling the pulse emission of reactant gas during the start-up process of a fuel cell according to claim 1, characterized in that, Also includes: After the pulse emission operation, the concentration of the impurity gas is compared with the actual concentration of the impurity gas obtained by sensor measurement or performance back-calculation; The correction factor of the dilution calculation model is adjusted based on the deviation of the comparison results.

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