A method for calculating multi-energy flow of fuel cell power generation system in steady state and dynamic state

Abstract

The application provides a kind of fuel cell power generation system steady and dynamic multi-energy flow calculation method, comprising: S1, fuel cell power generation system and single cell are divided according to structure, and are respectively decomposed into the form of low-dimensional system and single cell multi-energy flow resistance;S2, establish the steady state and dynamic model of fuel cell power generation system;S3, the model of steady state and dynamic process is verified;S4, obtain the system steady state condition electric energy flow, hydrogen energy flow, heat energy flow coupling parameter law;S5, obtain the system dynamic condition electric energy flow, hydrogen energy flow, heat energy flow coupling parameter law;S6, obtain the steady state of fuel cell power generation system electric-thermal-hydrogen coupling response and dynamic state electric-thermal-hydrogen coupling response result, guide actual design.The application can improve the accuracy and engineering practicability of model, provide theoretical basis and technical support for intelligent control, heat management optimization and dynamic performance improvement of fuel cell system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen energy power system, in particular, especially relates to a kind of fuel cell power generation system steady and dynamic multi-energy flow calculation method. BACKGROUND

[0002] Developing clean and efficient energy technology has become an important direction of global energy technology transformation. Proton exchange membrane fuel cell (PEMFC) has become an important energy conversion device in the fields of transportation, power system and renewable energy consumption due to its high power density, low operating temperature, fast response speed, no pollution emission and other significant advantages. Especially in hydrogen energy automobile, hydrogen power ship and distributed power supply and other applications, PEMFC is widely considered as a key technology path to realize clean and low-carbon energy system.

[0003] However, PEMFC system faces a series of complex challenges in actual operation. There is strong coupling between internal electric, thermal, gas (water) and other multi-physical fields, especially under dynamic load conditions, the response speed of each physical field is different, and the feedback path is complex, which easily causes voltage undershoot, temperature overshoot, water management imbalance and other problems, thereby affecting the performance, stability and life of the system. For example, under high dynamic load, due to gas supply lag, rapid change of electrochemical reaction rate, oxygen concentration is reduced in a short time, which causes local voltage drop of the stack, and causes uneven reaction and even membrane damage. In addition, the rapid accumulation of heat and the lag of heat dissipation may cause imbalance of temperature gradient, and then cause local overheating, accelerate material aging and other problems.

[0004] At present, a large number of studies have tried to model and optimize the operation characteristics of PEMFC system from the single perspective of electrochemistry, thermal management, gas supply and other aspects, but most of the research methods have the following shortcomings:

[0005] 1) Model dimension and applicability do not match: three-dimensional multi-physical modeling has high precision, but the calculation cost is too large, which is difficult to be embedded in actual control system; zero-dimensional simplified model ignores the internal structure details and transmission characteristics, and it is difficult to accurately reflect the actual coupling mechanism.

[0006] 2) Lack of systematic modeling of multi-field synergistic effect: most of the existing researches focus on the change law of a certain energy flow (such as electric field or thermal field), and less systematic analysis of the synergistic change mechanism of electric-thermal-hydrogen in steady state and dynamic process, especially ignoring the time lag, nonlinear response and superposition effect.

[0007] 3) Insufficient response to dynamic operating conditions: In actual applications, dynamic operating conditions such as vehicle acceleration, ship start-stop, etc. frequently occur. The existing model is prone to response lag and control disorder in processing the dynamic response process of the stack, and lacks accurate prediction and response to the transition process (such as voltage fluctuation, temperature lag, etc.).

[0008] Therefore, it is urgent to build a modeling method that takes into account the accuracy and real-time performance, which can simultaneously describe the energy transmission process at the system level and the membrane interface level, and comprehensively reflect the multi-energy flow coupling behavior of the PEMFC system under steady-state and dynamic conditions.

[0009] Currently, the research on proton exchange membrane fuel cell (PEMFC) system mainly focuses on its electrochemical performance analysis, thermal management optimization, gas supply system modeling and control strategy. Common modeling methods include zero-dimensional static model, one-dimensional steady-state simulation model and multi-physical field three-dimensional coupled simulation model, etc. These methods can respectively reflect the voltage characteristics, temperature distribution or gas concentration change of the fuel cell in specific application scenarios, providing basic support for understanding the system operation mechanism.

[0010] In the aspect of steady-state modeling, most studies use circuit equivalent models to predict the output voltage of the stack, combined with electrochemical reaction kinetics and ohmic loss formulas for parameter identification. However, such models are mostly limited to steady-state condition evaluation and cannot accurately describe the response process of the system under load mutation. In the aspect of thermal modeling, some studies use CFD methods for thermal conduction and cooling system simulation, but the calculation complexity is high and not suitable for real-time control system integration. Gas flow modeling mostly focuses on the pressure and flow changes of the anode and cathode gas supply system, and less on the coordinated modeling of internal reaction dynamics of the stack.

[0011] In addition, in response to dynamic operating conditions, existing research has attempted to introduce nonlinear predictive controllers, sliding mode control and disturbance observers, etc. intelligent algorithms to optimize the dynamic performance of the fuel cell. However, due to the lack of high-precision, multi-coupled system model support, these control strategies often rely on empirical parameters or experimental fitting, making it difficult to apply.

[0012] In summary, the existing technology still has significant deficiencies in the depth of coupled modeling, dynamic response modeling capability and systematic analysis. It is urgent to develop a high-efficiency modeling and regulation method that can simultaneously cover the electric, thermal and gas multi-energy flow transmission process, and adapt to steady-state and dynamic operating conditions, to support the high-performance operation and intelligent management of the PEMFC system under varying operating conditions. SUMMARY

[0013] According to the technical problems proposed above, a multi-energy flow calculation method for steady state and dynamic of fuel cell power generation system is provided. The present application discloses the internal energy flow response mechanism by constructing the electric-thermal-hydrogen multi-physical coupling topological model, which not only improves the accuracy and engineering practicability of the model, but also provides a theoretical basis and technical support for intelligent control, thermal management optimization and dynamic performance improvement of fuel cell system. The present application particularly introduces the heat flow topological modeling technology, realizes the dynamic modeling of temperature response process by means of the construction means of thermal resistance-thermal capacity network, and integrates the double-layer capacitance characterization in the equivalent circuit model to describe the voltage response lag characteristic, so as to uniformly describe the change law of key operating parameters such as temperature, voltage and gas pressure in the dynamic process. The method not only overcomes the shortcomings of traditional modeling methods, but also has high scalability, is suitable for various fuel cell application scenarios, and has significant technical innovation value and wide application prospect.

[0014] The technical means adopted by the present application are as follows:

[0015] A multi-energy flow calculation method for steady state and dynamic of fuel cell power generation system, comprising the following steps:

[0016] S1, the structure of the proton exchange membrane fuel cell power generation system is divided, and based on the generalized potential driving generalized flow theory, the proton exchange membrane fuel cell power generation system and the single cell are divided according to the structure, and are respectively decomposed into low-dimensional system and single cell multi-energy flow resistance form;

[0017] S2, based on the low-dimensional multi-energy flow decomposition result in S1, a steady state and dynamic model of the proton exchange membrane fuel cell power generation system is established;

[0018] S3, the parameters of the steady state and dynamic process model obtained in S2 are verified;

[0019] S4, according to the steady state model of the proton exchange membrane fuel cell power generation system, the steady state calculation of the proton exchange membrane fuel cell power generation system is carried out, the coupling parameter law of electric energy flow and hydrogen energy flow under the steady state condition of the system, the coupling parameter law of electric energy flow and thermal energy flow, and the coupling parameter law of hydrogen energy flow and thermal energy flow are obtained;

[0020] S5, according to the dynamic model of the proton exchange membrane fuel cell power generation system, the dynamic calculation of the proton exchange membrane fuel cell power generation system is carried out, the coupling parameter law of electric energy flow and hydrogen energy flow under the dynamic condition of the system, the coupling parameter law of electric energy flow and thermal energy flow, and the coupling parameter law of hydrogen energy flow and thermal energy flow are obtained;

[0021] S6, based on S4 and S5, multi-dimensional electric-thermal-hydrogen multi-energy flow steady state and dynamic calculation is carried out, the electric-thermal-hydrogen coupling response under the steady state of the proton exchange membrane fuel cell power generation system and the electric-thermal-hydrogen coupling response under the dynamic state are obtained, thereby guiding the actual design.

[0022] Further, in the S1, the structure division of the proton exchange membrane fuel cell power generation system includes: bipolar plate, flow channel layer, gas diffusion layer, microporous layer, anode, catalytic layer and proton exchange membrane, the bipolar plate includes anode bipolar plate and cathode bipolar plate, the gas diffusion layer includes anode gas diffusion layer and cathode gas diffusion layer, and the microporous layer includes anode microporous layer and cathode microporous layer.

[0023] Further, in the S2, the steady-state and dynamic model of the proton exchange membrane fuel cell power generation system includes: an electrical steady-state and dynamic model, a thermal steady-state and dynamic model, and a hydrogen steady-state and dynamic model, the electrical steady-state and dynamic model includes an electrochemical reaction model, an internal resistance model, and a fuel cell stack model, the thermal steady-state and dynamic model includes a thermal interface scale flow model, a component-level thermal flow model, and a system-level thermal flow model, and the hydrogen steady-state and dynamic model includes a substance transport model, a mass conservation model, and a hydrogen supply model.

[0024] Further, the electrical steady-state model satisfies the following formula:

[0025] ;

[0026] Wherein,

[0027] ;

[0028] ;

[0029] ;

[0030] ;

[0031] In the formula: is the output voltage of a single cell, , , are ohmic voltage, activation voltage, and concentration voltage, respectively; is the Nernst voltage, is the operating temperature of the battery pack, is the gas constant, is the Faraday constant, and are the effective partial pressures of hydrogen and oxygen; is the battery current, , , , are empirical parameters, which are different for different specific fuel cells; is the internal resistance of the battery; is the maximum current density of the battery, is the current density of the battery, is a correlation coefficient, obtained from fuel cell parameters.

[0032] Further, the electrodynamic model satisfies the following equation:

[0033] ;

[0034] ;

[0035] wherein,

[0036] ;

[0037] ;

[0038] ;

[0039] wherein, is the single cell voltage, is the output power, represents the number of single cells; is a time constant, denotes the equivalent resistance of the fuel cell, is the equivalent voltage, is a time term, C is a capacitance, is the cell current in the dynamic circuit.

[0040] Further, the thermal steady-state model comprises a stack steady-state heat flow balance, a proton exchange membrane heat flow balance, an anode catalyst layer heat flow balance, a cathode catalyst layer heat flow balance, a microporous layer heat flow balance, a gas diffusion layer heat flow balance, a channel layer heat flow balance, a bipolar plate layer heat flow balance;

[0041] The stack steady-state heat flow balance satisfies the following equation:

[0042] ;

[0043] wherein, is the heat dissipation of the fuel cell, is the molar flow of hydrogen consumption, denotes the higher heating value of hydrogen, is the average power of the fuel cell;

[0044] The proton exchange membrane heat flow balance satisfies the following equation:

[0045] ;

[0046] wherein, is the ohmic heat of the proton exchange membrane layer, is the thermal conduction of the cathode catalyst layer and the proton exchange membrane layer, is the conductive heat of the proton exchange membrane layer, is the convective heat of the proton exchange membrane layer;

[0047] The anode catalytic layer heat flow balance satisfies the following formula:

[0048] ;

[0049] wherein: is the ohmic heat of the anode catalytic layer, is the conductive heat of the proton exchange membrane layer, is the conductive heat of the anode catalytic layer, is the convective heat of the anode catalytic layer;

[0050] The cathode catalytic layer heat flow balance satisfies the following formula:

[0051] ;

[0052] wherein: is the ohmic heat of the cathode catalytic layer, is the activation heat of the cathode catalytic layer, is the conductive heat of the cathode catalytic layer and the proton exchange membrane layer, is the convective heat of the cathode catalytic layer;

[0053] The microporous layer heat flow balance satisfies the following formula:

[0054] ;

[0055] wherein: is the ohmic heat of the microporous layer, is the conductive heat of the cathode catalytic layer and the microporous layer, is the self-conductive heat of the microporous layer, is the convective heat of the microporous layer;

[0056] The gas diffusion layer heat flow balance satisfies the following formula:

[0057] ;

[0058] wherein: is the ohmic heat of the gas diffusion layer, is the conductive heat of the microporous layer, is the conductive heat of the gas diffusion layer, is the convective heat of the gas diffusion layer;

[0059] The channel layer heat flow balance satisfies the following formula:

[0060] ;

[0061] wherein: is the gas exhaust heat, Qin is the heat entering the bipolar plate layer, Qconv is the heat convected through the channel;

[0062] The heat balance of the bipolar plate layer satisfies the following equation:

[0063] ;

[0064] wherein: Qohm is the ohmic heat of the bipolar plate layer, Qcond is the conductive heat of the gas diffusion layer, Qcool is the cooling heat of the bipolar plate, Qconv is the convective heat of the bipolar plate.

[0065] Further, the thermal dynamic model satisfies the following equation:

[0066] ;

[0067] wherein: C is the product of the heat capacity and the mass of any one of the proton exchange membrane, the anode and cathode catalyst layers, the bipolar plate, the gas diffusion layer, and the microporous layer, i is an object value, T is a temperature, t is a time term, Q is a heat.

[0068] Further, the gas dynamic model satisfies the following equation:

[0069] ;

[0070] ;

[0071] wherein: t is a time term, Nin and Nout are the mole numbers of oxygen at the cathode, wherein the subscripts in and out represent the input and output of the fuel cell, Nchem is the mole number of oxygen actually involved in the electrochemical reaction, Nin is the mole number of hydrogen at the anode, Nchem is the mole number of hydrogen actually involved in the electrochemical reaction, Nnit is the mole number of nitrogen at the cathode, Nwater is the mole number of water, Nwaterchem is the mole number of water produced in the electrochemical reaction; Pcath is the cathode pressure, R is the gas constant of air, Tcath is the cathode temperature, Vcath is the volume of the cathode, Mcathin is the mass of the gas entering the cathode, Mcathout is the mass of the gas leaving the cathode, R is the gas constant of oxygen, The mass of oxygen is reacted.

[0072] Further, the gas steady-state model satisfies the following formula:

[0073] ;

[0074] .

[0075] Further, in the S6, the guiding actual design includes: guiding the proton exchange membrane fuel cell system in the fuel cell stack structure optimization design, the air and hydrogen supply system design, the heat management system configuration and the control parameter setting, the system selection and the power matching scheme formulation.

[0076] Compared with the prior art, the present application has the following advantages:

[0077] 1. The fuel cell power generation system steady-state and dynamic multi-energy flow calculation method provided by the present application realizes unified modeling and response analysis of electric-thermal-hydrogen three types of energy flow under steady-state and dynamic working conditions, fills the technical gap that existing models cannot accurately describe the multi-physical field coupling behavior. By introducing the thermal resistance-thermal capacity network and the double-layer capacitor structure, the dynamic phenomena such as voltage drop, temperature delay and gas response lag of the system during load change can be effectively described.

[0078] 2. The fuel cell power generation system steady-state and dynamic multi-energy flow calculation method provided by the present application takes into account the dual-scale modeling requirements of the system level and the membrane interface level, not only reveals the power output law of the fuel cell stack as a whole, but also deeply analyzes the heat conduction path and water management mechanism in the membrane electrode structure, providing theoretical support for the linkage optimization of system micro-behavior and macro-performance.

[0079] 3. The fuel cell power generation system steady-state and dynamic multi-energy flow calculation method provided by the present application, compared with the traditional three-dimensional CFD model, adopts a low-dimensional and modular modeling method, which greatly reduces the calculation burden on the basis of ensuring the calculation precision, is convenient for embedded deployment in real-time applications such as vehicle controllers and ship energy management systems, and is helpful to realize online prediction, dynamic regulation and fault diagnosis of fuel cell systems.

[0080] 4. The fuel cell power generation system steady-state and dynamic multi-energy flow calculation method provided by the present application can realize response time optimization, voltage stability improvement and thermal safety guarantee of the fuel cell system under different load fluctuation conditions through modeling and regulation methods, significantly improve the system operation efficiency and life, and has wide engineering adaptability and popularization value.

[0081] 5、The fuel cell power generation system steady-state and dynamic multi-energy flow calculation method provided by the application can be applied to hydrogen energy automobile, hydrogen power ship, distributed energy and other low-carbon energy equipment fields, and promotes the intelligent and systematic development of fuel cell technology. The electric-thermal-hydrogen energy flow coupling response not only provides quantitative design reference parameters, but also constructs a logical atlas of the coupling feedback mechanism in the system, which can be used as an important guide for system engineers when designing and optimizing the key sub-modules of the PEMFC system, and accelerates the transition from the "trial and error - improvement" mode to the intelligent design paradigm of "modeling - prediction - optimization".

[0082] Based on the above reasons, the application can be widely popularized in the fields of new energy vehicles, ship propulsion, power storage and distributed energy. BRIEF DESCRIPTION OF DRAWINGS

[0083] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0084] Figure 1 The PEMFC system multi-energy flow deconstruction and reconstruction method framework of the application.

[0085] Figure 2 The energy flow resistance deconstruction diagram of the fuel cell power generation system of the application.

[0086] Figure 3 The thermal resistance and thermal capacity network diagram of the fuel cell single cell of the application.

[0087] Figure 4 The coupling parameter law diagram of the electric energy flow and hydrogen energy flow under steady-state conditions of the application.

[0088] Figure 5 The coupling parameter law diagram of the electric energy flow and thermal energy flow under steady-state conditions of the application.

[0089] Figure 6 The coupling parameter law diagram of the hydrogen energy flow and thermal energy flow under steady-state conditions of the application.

[0090] Figure 7 The coupling parameter law diagram of the electric energy flow and hydrogen energy flow under transient conditions of the application.

[0091] Figure 8 The coupling parameter law diagram of the electric energy flow and thermal energy flow under transient conditions of the application.

[0092] Figure 9A coupling parameter law diagram of hydrogen energy flow and heat energy flow under transient conditions of the present application.

[0093] Figure 10 A coupling result diagram of electric energy flow, heat energy flow and hydrogen energy flow of the present application. DETAILED DESCRIPTION

[0094] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0095] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0096] It should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and it should also be understood that when the terms "comprise" and / or "include" are used in the specification, there is a presence of the features, steps, operations, devices, components and / or combinations thereof.

[0097] Unless specifically stated otherwise, the relative arrangement of components and steps, numerical expressions, and numerical values set forth in the various embodiments described herein are not limiting. It should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn in accordance with the actual proportional relationship. The technology, methods and devices known to those skilled in the relevant art can not be discussed in detail, but should be considered as part of the specification under appropriate circumstances. In all examples shown and discussed herein, any specific value should be interpreted as merely exemplary, and not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0098] Embodiment 1

[0099] In recent years, hydrogen energy and fuel cell technology are considered as an important part of the future clean energy system. Proton exchange membrane fuel cell (PEMFC) has the advantages of fast start-up speed, high energy density, no pollution emission, etc., and is especially suitable for mobile carriers with high requirements for dynamic response and energy efficiency, such as hydrogen fuel vehicles, hydrogen energy ships, rail transit, etc. However, due to the strong coupling of electric-thermal-hydrogen multi-physical fields inside the PEMFC system, its performance will be affected by factors such as transient load change, reaction gas supply lag, uneven temperature distribution, etc. in actual operation, resulting in voltage fluctuation, system efficiency decline and even thermal runaway. The present application provides a kind of fuel cell power generation system steady and dynamic multi-energy flow calculation method, which is a new type of energy flow deconstruction-reconstruction modeling method, i.e. a multi-energy flow deconstruction-reconstruction modeling method, which can accurately depict the electric, thermal and hydrogen energy flow rules under steady state and dynamic conditions in the fuel cell system, realize the multi-physical field collaborative simulation across scales and fields, and provide theoretical basis and engineering tool for system optimization design, dynamic control strategy formulation, intelligent energy management and online fault warning. The present application is especially suitable for the control optimization of hydrogen fuel vehicle power system, the energy efficiency evaluation and safety protection of marine fuel cell power device, the collaborative operation strategy design of PEMFC in intelligent microgrid and renewable energy system, etc. It has good engineering adaptability and industrialization prospect. The present application can be widely applied in new energy vehicles, ship propulsion, power storage and distributed energy, etc.

[0100] The present application is a kind of fuel cell power generation system steady and dynamic multi-energy flow calculation method, which is a multi-energy flow deconstruction-reconstruction modeling and control method for proton exchange membrane fuel cell (PEMFC) power generation system.

[0101] I. Constructing the multi-energy flow calculation method framework of PEMFC power generation system, as shown in Figure 1 First, the steady state and dynamic models are established in sequence according to electricity, heat and hydrogen, including electric steady state and dynamic models, including electrochemical reaction model, internal resistance model, fuel cell stack model; thermal steady state and dynamic models, including thermal interface scale flow model, component level thermal flow model, system level thermal flow model; hydrogen steady state and dynamic models, including mass transport model, mass conservation model, hydrogen supply model; secondly, the model parameters of steady state and dynamic process are verified; finally, the multi-energy flow (electricity, heat and hydrogen) parameter coupling response calculation of PEMFC power generation system case is carried out, and the steady state parameter coupling response and transient (dynamic) parameter response results are highlighted.

[0102] II. The structure of the conventional PEMFC power generation system is divided as follows: bipolar plates (BP) including anode bipolar plates (ABP) and cathode bipolar plates (CBP), which are responsible for reactant distribution; channel layers (CHA), gas diffusion layers (GDL) including anode gas diffusion layers (AGDL) and cathode gas diffusion layers (CGDL), which manage gas transport and drainage; microporous layers (MPL) including anode microporous layers (AMPL) and cathode microporous layers (CMPL), which balance drainage and airflow; anode and cathode catalyst layers (ACL and CCL), which drive redox reactions; and proton exchange membranes (MEM), which allow protons to pass but block electrons and gases. Based on the generalized potential driving generalized flow theory, the PEMFC power generation system and single cell are decomposed into low-dimensional systems and single cell multi-energy flow resistances in the form of, for example, Figure 1 and 2 .

[0103] III. Based on the low-dimensional multi-energy flow decomposition results, a steady-state and transient model of the PEMFC power generation system is established, which consists of three main modules: an electrical steady-state and dynamic model, a thermal steady-state and dynamic model, and a hydrogen steady-state and dynamic model, as follows:

[0104] 1) Electrical steady-state model:

[0105] The PEMFC power decomposition model is based on a circuit model. As shown in Figure 3 , the equivalent internal voltage, also known as the Nernst voltage , and the equivalent resistance are , and represent the activation resistance, ohmic resistance, and concentration resistance, respectively, and the basic equation for the output voltage of a single cell is obtained as:

[0106] .

[0107] In the equation, , , are the ohmic voltage, activation voltage, and concentration voltage, respectively.

[0108] The Nernst voltage is:

[0109] .

[0110] In the equation, is the stack operating temperature, is the gas constant, is the Faraday constant, and are the effective partial pressures of hydrogen and oxygen.

[0111] The charge transfer occurring at the electrode-electrolyte interface leads to the creation of an activation voltage :

[0112] ;

[0113] where: is the battery current, , , , is an empirical parameter that varies depending on the specific fuel cell.

[0114] Ohmic voltage is caused by the internal resistance of the assembly:

[0115] ;

[0116] where: is the internal resistance of the battery.

[0117] Concentration voltage is caused by the difference in concentration of reactants and products at the electrode surface :

[0118] ;

[0119] where: is the maximum current density of the battery, is the current density of the battery, is a correlation coefficient that can be obtained from the parameters of the fuel cell.

[0120] 2) Electrodynamic model:

[0121] In dynamic operating mode, the operating parameters of the PEMFC fluctuate as a function of the load, as shown in Figure 3 , the transient effects of the electrochemistry are described by introducing an equivalent capacitor C in the circuit, the voltage across which varies dynamically as a function of the load current until a steady state is reached. The dynamic behavior of this circuit can be described by the following differential equation:

[0122] ;

[0123] ;

[0124] ;

[0125] where: is the time constant, denotes the equivalent resistance of the fuel cell, is the equivalent voltage, is the time term, C is the capacitance, Battery current in dynamic circuit.

[0126] The transient voltage in dynamic mode of operation with integrated equivalent capacitor can thus be expressed as:

[0127] ;

[0128] where: is the single cell voltage.

[0129] Output power can be expressed as:

[0130] ;

[0131] where: represents the number of single cells.

[0132] 3) Thermal steady state model

[0133] As shown in Figure 1 , the fuel cell thermodynamic steady state model employs standard thermal resistances, whose heat flow balances are expressed as follows:

[0134] Stack steady state heat flow balance:

[0135] ;

[0136] where: is the heat dissipation of the fuel cell, is the molar flow of hydrogen consumption, represents the higher heating value of hydrogen, is the average power of the fuel cell.

[0137] Proton exchange membrane heat flow balance:

[0138] ;

[0139] where: is the ohmic heat of the proton exchange membrane layer, is the thermal conduction of the cathode catalyst layer and the proton exchange membrane layer, is the thermal conduction of the proton exchange membrane layer, is the convective heat of the proton exchange membrane layer.

[0140] Anode catalyst layer heat flow balance:

[0141] ;

[0142] where: is the ohmic heat of the anode catalyst layer, is the thermal conduction of the proton exchange membrane layer, is the thermal conduction of the anode catalyst layer, Convection heat from the anode catalyst layer.

[0143] Cathode catalyst layer heat flow balance:

[0144] ;

[0145] where: Ohmic heat from the cathode catalyst layer, Activation heat from the cathode catalyst layer, Thermal conduction from the cathode catalyst layer to the proton exchange membrane layer, Convection heat from the cathode catalyst layer.

[0146] Microporous layer heat flow balance:

[0147] ;

[0148] where: Ohmic heat from the microporous layer, Thermal conduction from the cathode catalyst layer to the microporous layer, Thermal conduction from the microporous layer itself, Convection heat from the microporous layer.

[0149] Gas diffusion layer heat flow balance:

[0150] ;

[0151] where: Ohmic heat from the gas diffusion layer, Thermal conduction from the microporous layer, Thermal conduction from the gas diffusion layer, Convection heat from the gas diffusion layer.

[0152] Channel layer heat flow balance:

[0153] ;

[0154] where: Gas exit heat, Gas entry heat, Channel heat convection.

[0155] Bipolar plate layer heat flow balance:

[0156] ;

[0157] where: Ohmic heat from the bipolar plate layer, Thermal conduction from the gas diffusion layer, Cooling heat from the bipolar plate, Convection heat from the bipolar plate.

[0158] 4) Thermal dynamic model

[0159] The thermodynamic transient heat flow balance equation, i.e. adding temperature and time terms to the above steady-state model, is:

[0160]

[0161] In the formula: C is the product of the heat capacity and mass of any one of the proton exchange membrane (MEM), anode and cathode catalyst layer (ACL and CCL), bipolar plate (BP), gas diffusion layer (GDL), microporous layer (MPL), etc. i is the value of the above-mentioned object, T is the temperature, t is the time term, Q is the heat.

[0162] 5) Aerodynamic model

[0163] Based on the changes of gas parameters in the flow channel, the gas flow model of the single-layer PEMFC dynamic operation mode is established:

[0164]

[0165] In the formula: t is the time term, is the number of moles of cathode oxygen, and subscripts in and out represent the inlet and outlet of the fuel cell, is the number of moles of oxygen actually undergoing electrochemical reaction, is the number of moles of hydrogen at the anode, is the number of moles of hydrogen actually undergoing electrochemical reaction, is the number of moles of nitrogen at the cathode, is the number of moles of water, is the number of moles of water produced in the electrochemical reaction.

[0166] The dynamic changes of the pressure reduction process controlled by the valve in the system can be defined by the ideal gas law and the electrochemical equation:

[0167]

[0168] In the formula: is the cathode pressure, is the gas constant of air, is the cathode temperature, is the volume of the cathode, is the mass of gas entering the cathode, is the mass of gas leaving the cathode, is the gas constant of oxygen, is the mass of oxygen reaction.

[0169] ​​​6) Gas steady-state model

[0170] In the steady-state operation mode, The change disappears, and the above gas dynamics model can be changed to:

[0171] ;

[0172] ;

[0173] In the formula, the relevant letter parameters are consistent with the dynamic model.

[0174] Four, according to the above-mentioned steady-state model of the PEMFC power generation system, further obtain the coupling parameter law of electric energy flow and hydrogen energy flow under the steady-state condition of the system, the coupling parameter law of electric energy flow and thermal energy flow, and the coupling parameter law of hydrogen energy flow and thermal energy flow, as shown in Figures 4-6 .

[0175] Five, according to the above-mentioned dynamic model, the dynamic calculation of the PEMFC power generation system is further obtained, and the coupling parameter law of electric energy flow and hydrogen energy flow under the dynamic condition of the system, the coupling parameter law of electric energy flow and thermal energy flow, and the coupling parameter law of hydrogen energy flow and thermal energy flow are obtained, as shown in Figures 7-9 .

[0176] Six, on the basis of the above, multi-dimensional electric-thermal-hydrogen multi-energy flow steady-state and dynamic calculation is carried out, and the electric-thermal-hydrogen coupling response under the steady-state condition of the PEMFC power generation system and the electric-thermal-hydrogen coupling response under the dynamic condition are further obtained, thereby guiding the actual design (guiding the optimization design of fuel cell stack structure, air and hydrogen supply system design, thermal management system configuration and control parameter setting, system selection and power matching scheme formulation), as shown in Figure 10 .

[0177] Specifically, the response characteristics of the three types of energy flow of electric-thermal-hydrogen under the steady-state and dynamic conditions can guide the optimization and engineering landing of the proton exchange membrane fuel cell (PEMFC) system in the optimization of fuel cell stack structure, air and hydrogen supply system design, thermal management system configuration and control parameter setting, system selection and power matching scheme formulation, etc. The specific guidance includes the following aspects:

[0178] 1) Optimization design of fuel cell stack structure: the coupling response reveals the key heat source and heat bottleneck, and the application discloses the heat transfer law that the catalyst layer (CCL) is the main heat source and the gas channel is the weak area of temperature distribution, which helps to design more reasonable heat dissipation channel layout and cooling medium flow path, and improves the overall thermal management efficiency. The quantitative analysis of the membrane interface temperature gradient and the voltage output can optimize the membrane thickness, catalyst layer coating strategy and porous layer structure, and improve the reaction uniformity and membrane life.

[0179] 2) Air and hydrogen supply system design: air pressure-voltage coupling guides air compressor selection and control strategy, dynamic response results show that the cathode pressure affects the degree of short-time voltage fluctuation, providing parameters such as air compressor start-stop logic, throttle valve adjustment speed for setting basis. Based on load prediction, the gas supply redundancy design, the flow lag phenomenon of hydrogen and oxygen in the system under dynamic working conditions, can be used to guide the preloading or set the buffer volume of the hydrogen supply system, and improve the response sensitivity and system stability.

[0180] 3) Configuration and control parameter setting of thermal management system: establish the correspondence between load-temperature rise-heat dissipation rate, design the cooling water flow rate dynamic adjustment strategy based on the obtained heat capacity characteristics and temperature delay law, avoid overcooling or overheating problem, reduce energy consumption. Optimize the structure design of cooling system: based on the heat flow distribution law, reasonably configure the position of water cooling plate and the structure of loop, improve the system thermal coupling efficiency and safety margin.

[0181] 4) System selection and power matching scheme development: electric-thermal-hydrogen coupling characteristics provide multi-field design boundaries, analyze the coupling boundaries under different power levels, which is helpful to evaluate the feasibility of system design parameters such as single stack size, heat exchanger power, humidifier capacity, etc., and support the development of ship / car integrated system integration scheme.

[0182] The multi-energy flow deconstruction-reconstruction modeling and regulation method for a proton exchange membrane fuel cell (PEMFC) power generation system of the application has significant technical progress and application value, mainly reflected in the following aspects:

[0183] Firstly, the application realizes the unified modeling and response analysis of electric-thermal-hydrogen three types of energy flow under steady state and dynamic working conditions, filling the technical gap that existing models cannot accurately describe the multi-physical field coupling behavior. By introducing thermal resistance-thermal capacity network and double-layer capacitor structure, the dynamic phenomena such as voltage drop, temperature delay and gas response lag during load change can be effectively described.

[0184] Secondly, the energy flow topology structure constructed by the application takes into account the dual-scale modeling needs of system level and membrane interface level, not only reveals the power output law of fuel cell stack as a whole, but also deeply analyzes the heat conduction path and water management mechanism in the membrane electrode structure, providing theoretical support for the linkage optimization of system micro behavior and macro performance.

[0185] Thirdly, compared with the traditional three-dimensional CFD model, the application adopts low-dimensional and modular modeling method, which greatly reduces the calculation burden on the basis of ensuring the calculation accuracy, is convenient for embedded deployment in real-time applications such as vehicle controller and ship energy management system, and is helpful to realize online prediction, dynamic regulation and fault diagnosis of fuel cell system.

[0186] Finally, the modeling and control methods provided by this invention can optimize the response time, improve voltage stability, and ensure thermal safety of fuel cell systems under different load fluctuation conditions, significantly improving system operating efficiency and lifespan, and possessing broad engineering adaptability and promotional value. It can be applied to multiple low-carbon energy equipment fields such as hydrogen-powered vehicles, hydrogen-powered ships, and distributed energy, promoting the intelligent and systematic development of fuel cell technology. The coupled response of the electro-thermal-hydrogen flow not only provides quantitative design reference parameters but also constructs a logical diagram of the coupling feedback mechanism within the system. This can serve as an important guideline for system engineers when designing and optimizing key sub-modules of the PEMFC system, accelerating the shift from a "trial and error – improvement" model to a "modeling – prediction – optimization" intelligent design paradigm.

[0187] Example 2

[0188] I. Following the steady-state model mentioned in steps one through three of Example 1, perform steady-state calculations of the PEMFC power generation system to further obtain the coupling parameters of electrical energy flow and hydrogen energy flow, the coupling parameters of electrical energy flow and thermal energy flow, and the coupling parameters of hydrogen energy flow and thermal energy flow under steady-state conditions, such as... Figures 4-6 As shown.

[0189] The electro-pneumatic coupling response under steady-state operation was assessed under normal operating conditions. The throttle valve opening was fixed at 27°C, the stack temperature was maintained at 80°C, and the excess hydrogen and oxygen ratios were set to 1.2 and 2, respectively. To prevent membrane damage, the voltage difference between the anode and cathode should not exceed 50 kPa; therefore, the load current density was controlled between 0.45 and 0.6 A / s. Between 0.45 A and 0.5 A. Within this range, the coupled response characteristics are obtained by calculating the response processes of electrical and gaseous energy flows. As the current density increases from 0.45 A / Increased to 0.6A / The cathode pressure increased from 255.24 kPa to 347.03 kPa, equivalent to an increase of 35.96%. According to Faraday's law, an increase in current density accelerates the electrochemical reaction rate and oxygen consumption. With a constant gas excess rate, the inlet flow rate increases linearly with the load. However, due to the fixed opening of the cathode outlet valve, gas emission is restricted, leading to reactant accumulation within the flow channel. Furthermore, the cathode pressure affects the permeate flow rate, further altering the fluid transport dynamics. Therefore, the mismatch between inflow and outflow rates causes the cathode pressure to increase nearly linearly within the study range. Notably, Figure 4The results in FIG. 6 only reflect the trend of cathode pressure and gas flow rate with respect to the load current density. Since the valve opening and gas excess ratio are controllable, the cathode pressure is kept in an appropriate range within this load current density range. This is to emphasize the coupling relationship between the cathode pressure and the load current density under the condition of controlled variables. If the selected load current density range changes, the air supply subsystem needs to be readjusted to ensure that the pressure difference remains within a reasonable range.

[0190] Figure 5 The cell temperature is a key parameter in the operation of a proton exchange membrane fuel cell (PEMFC). To highlight the temperature change, the cooling water flow rate is fixed at 0.1 kg / s, and the inlet temperature is 303.15 K. The results of the coupling of electrical and thermal energy flows are calculated at different current densities. The results show that, as the load current density increases (0-1.4 A / cm2), the temperature of all components rises, with the largest temperature change in the CCL (72.98 K) and the smallest temperature change in the CHA gas region. The solid parts exhibit strong thermal consistency, with little difference between them (e.g., only 0.605 K between the CCL and CBP at 0.9 A / cm2), while the temperature difference between the solid and gas phases is large (up to 26.371 K between the CCL and CHA). The main heat source is the reaction heat in the CCL, while the ohmic heating in the solid contributes less. At low load density, the reaction rate is slow and the gas preheating causes the gas phase temperature to be higher than the solid. The results in FIG. 6 only reflect the trend of cathode pressure and gas flow rate with respect to the load current density. Since the valve opening and gas excess ratio are controllable, the cathode pressure is kept in an appropriate range within this load current density range. This is to emphasize the coupling relationship between the cathode pressure and the load current density under the condition of controlled variables. If the selected load current density range changes, the air supply subsystem needs to be readjusted to ensure that the pressure difference remains within a reasonable range.

[0191] Figure 6 The results in FIG. 6 only reflect the trend of cathode pressure and gas flow rate with respect to the load current density. Since the valve opening and gas excess ratio are controllable, the cathode pressure is kept in an appropriate range within this load current density range. This is to emphasize the coupling relationship between the cathode pressure and the load current density under the condition of controlled variables. If the selected load current density range changes, the air supply subsystem needs to be readjusted to ensure that the pressure difference remains within a reasonable range.

[0192] ​​II. Dynamic calculation of the PEMFC power generation system according to the dynamic model mentioned above, further obtaining the coupling parameter law of electric energy flow and hydrogen energy flow under the dynamic condition of the system, the coupling parameter law of electric energy flow and thermal energy flow, and the coupling parameter law of hydrogen energy flow and thermal energy flow, as shown in Figures 7-9

[0193] Figure 7 The coupling change relationship between electric energy flow and gas energy flow is shown. When the load current changes, due to the change of the electrochemical reaction rate, it will lead to the change of the gas flow rate and the cell stack temperature, and further lead to the dynamic change of the cathode pressure. It is obvious that when the load current increases at 1000s and 2500s, the consumption rate of the reaction gas will surge. According to the relationship between the consumption of hydrogen and oxygen revealed by the electrochemical reaction equation, since the consumption of hydrogen is greater than that of oxygen, the change of the molar flow is more significant. At the same time, since the electrochemical reaction inside the cell is an exothermic reaction, the change of the load current will lead to the change of the electrochemical reaction rate, thus leading to the change of the heat source heat release.

[0194] Figure 8 is the change of electric energy flow and thermal energy flow, the cell temperature changes to a certain extent following the change of the load current, and the change amplitude is related to the size of the current step. However, compared with the almost instantaneous change of the load current, the change of the component temperature occurs more slowly. First of all, the load current is a direct manifestation of the electrochemical reaction rate, which is a fast process that can change on the time scale of milliseconds. Therefore, the change of the load current is almost instantaneous. At the same time, the reaction is an exothermic reaction, and the change of the reaction rate will lead to the change of the heat released, thus leading to the change of the temperature. However, due to the heat capacity of the components, a large amount of heat needs to be absorbed and released for the change of the temperature in the system. In addition, due to the limitation of physical properties, the heat transfer process is delayed in time, leading to the generation of thermal inertia. Therefore, although the heat generation in the electrochemical reaction is instantaneous, due to the existence of thermal inertia, the temperature change needs a certain time to reflect.

[0195] Figure 9 ​is the coupling response of thermal and gas energy flow. When the fuel cell works, the heat generated by the reaction is closely related to the gas flow. When the cathode pressure changes, the fuel cell temperature first rises and then stabilizes, and the temperature change amplitude is related to the pressure change amplitude. The deconstruction and reconstruction of gas and thermal energy flow show that this is due to the decrease of the cathode pressure, which leads to the decrease of the oxygen partial pressure. The decrease of the oxygen partial pressure directly reduces the open-circuit voltage of the cell, but also reduces the working voltage. The difference between the two represents the actual loss of the cell. Since the load current remains constant, the voltage difference increases as the cathode pressure decreases. Therefore, the heat generated due to the loss inside the cell increases, resulting in an upward trend in the temperature of the cell stack. Even in the case of the largest change in cathode pressure, the fuel cell temperature only increases by 0.46 K, indicating that the change in cathode pressure is minimal.

[0196] III. On the basis of the above, multi-dimensional electro-thermal-hydrogen multi-energy flow steady-state and dynamic calculation is carried out, and the results of the electro-thermal-hydrogen coupling response of the PEMFC power generation system in the steady-state and the electro-thermal-hydrogen coupling response in the dynamic state are further obtained, thereby guiding the actual design. For example, Figure 10As shown, the three-dimensional coupled responses of the electric, thermal, and gas energy flows to the PEMFC power generation system under steady-state conditions, with fixed cooling flow rate and valve opening, the load current is the only independent variable. As the current increases from 125 A to 165 A, both the cell stack temperature and the cathode pressure increase, resulting in a general increase in the output voltage. This relationship is non-monotonic. The highest voltage (548.64 V) occurs at 163.19 A, 343.01 kPa, and 354.13 K, rather than the absolute peak of a single parameter. The cathode pressure is taken as the second independent variable (250-350 kPa). Although the cell stack temperature is still closely related to the load current, its dependence on the cathode pressure is non-linear, indicating a weak thermal-gas coupling. The voltage increases non-monotonically along both the load current and the cathode pressure directions. The highest voltage (548.64 V) still occurs at 163.19 A and 343.01 kPa, confirming the dominant role of the electro-thermal synergy over the gas effect. The stack temperature is randomized as the second variable (333.15-353.15 K). Here, the cathode pressure is related to the load current, but the voltage trend is different: it decreases with increasing current but increases with increasing temperature. The maximum voltage (558.77 V) occurs at moderate current (128.81 a) and high temperature (352.28 K), emphasizing the importance of temperature in optimizing the reaction efficiency. When the cooling and gas systems remain constant, increasing the current raises the cell stack temperature and the cathode pressure, but also increases the internal resistance. The voltage increase is not simply due to the current, but to the offsetting effect of improved thermal and pressure conditions. Crucially, the optimal voltage output does not coincide with the highest value of the current, temperature, or pressure, but comes from the multi-field coupled synergy. This confirms that single-variable analysis can distort the behavior of PEMFCs, highlighting the necessity of multi-energy field coordination for accurate performance evaluation.

[0197] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system, characterized in that, Includes the following steps: S1. The proton exchange membrane fuel cell power generation system is structurally divided, and based on the generalized potential-driven generalized flow theory, the proton exchange membrane fuel cell power generation system and the single cell are structurally divided and decomposed into the form of low-dimensional system and single cell multi-energy flow resistance, respectively. S2. Based on the low-dimensional multi-energy flow deconstruction results in S1, establish steady-state and dynamic models of the proton exchange membrane fuel cell power generation system; S3. Perform parameter verification on the steady-state and dynamic process models obtained in S2; S4. Based on the steady-state model of the proton exchange membrane fuel cell power generation system, perform steady-state calculations of the proton exchange membrane fuel cell power generation system to obtain the coupling parameter laws of electrical energy flow and hydrogen energy flow, electrical energy flow and thermal energy flow, and hydrogen energy flow and thermal energy flow under steady-state conditions. S5. Based on the dynamic model of the proton exchange membrane fuel cell power generation system, perform dynamic calculations on the proton exchange membrane fuel cell power generation system to obtain the coupling parameter laws of electrical energy flow and hydrogen energy flow, the coupling parameter laws of electrical energy flow and thermal energy flow, and the coupling parameter laws of hydrogen energy flow and thermal energy flow under the dynamic conditions of the system. S6. Based on S4 and S5, perform multi-dimensional steady-state and dynamic calculations of the electro-thermal-hydrogen multi-energy flow to obtain the electro-thermal-hydrogen coupling response under steady-state and dynamic states of the proton exchange membrane fuel cell power generation system, thereby guiding practical design. In S1, the structure of the proton exchange membrane fuel cell power generation system includes: bipolar plate, flow channel layer, gas diffusion layer, microporous layer, anode, catalyst layer and proton exchange membrane. The bipolar plate includes an anode bipolar plate and a cathode bipolar plate. The gas diffusion layer includes an anode gas diffusion layer and a cathode gas diffusion layer. The microporous layer includes an anode microporous layer and a cathode microporous layer. In S2, the steady-state and dynamic models of the proton exchange membrane fuel cell power generation system include: an electrical steady-state and dynamic model, a thermal steady-state and dynamic model, and a hydrogen steady-state and dynamic model. The electrical steady-state and dynamic model includes an electrochemical reaction model, an internal resistance model, and a fuel cell stack model. The thermal steady-state and dynamic model includes a thermal interface-scale heat flow model, a component-level heat flow model, and a system-level heat flow model. The hydrogen steady-state and dynamic model includes a mass transport model, a mass conservation model, and a hydrogen supply model.

2. The method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system according to claim 1, characterized in that, The electrical steady-state model satisfies the following formula: ； in, ； ； ； ； In the formula: For the output voltage of a single battery, , , These are the ohmic voltage, activation voltage, and concentration voltage, respectively. For Nernst voltage, The operating temperature of the battery pack. The gas constant is... It is Faraday's constant. and The effective partial pressure of hydrogen and oxygen; Battery current, , , , These are empirical parameters and vary depending on the specific fuel cell. This refers to the internal resistance of the battery. This represents the battery's maximum current density. The current density of the battery, The correlation coefficient is obtained based on the fuel cell parameters.

3. The method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system according to claim 2, characterized in that, The electrodynamic model satisfies the following formula: ； ； in, ； ； ； In the formula: For single cell voltage, For output power, Represents the number of individual cells; It is a time constant. This represents the equivalent resistance of the fuel cell. Equivalent voltage For time terms, C For capacitors, This refers to the battery current in a dynamic circuit.

4. The method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system according to claim 1, characterized in that, The thermal steady-state model includes the steady-state heat flow balance of the fuel cell stack, the heat flow balance of the proton exchange membrane, the heat flow balance of the anode catalyst layer, the heat flow balance of the cathode catalyst layer, the heat flow balance of the microporous layer, the heat flow balance of the gas diffusion layer, the heat flow balance of the channel layer, and the heat flow balance of the bipolar plate layer. The steady-state heat flow balance of the fuel cell stack satisfies the following formula: ； In the formula: For heat dissipation of fuel cells, The molar flow rate of hydrogen consumed. This indicates the higher heating value of hydrogen. The average power of the fuel cell; The heat flow equilibrium of the proton exchange membrane satisfies the following formula: ； In the formula: For the ohmic heat of the proton exchange membrane, For heat conduction between the cathode catalytic layer and the proton exchange membrane layer, For the thermal conductivity of the proton exchange membrane, The heat generated by the convection of the proton exchange membrane. The heat flow balance of the anode catalyst layer satisfies the following formula: ； In the formula: For the ohmic heat of the anode catalyst layer, For the thermal conductivity of the proton exchange membrane, For the thermal conductivity of the anode catalyst layer, The heat generated is the convective heat of the anode catalyst layer; The heat flow balance of the cathode catalyst layer satisfies the following formula: ； In the formula: For the ohmic heat of the cathode catalyst layer, The activation heat of the cathode catalyst layer, For heat conduction between the cathode catalytic layer and the proton exchange membrane layer, The heat generated is the convective heat of the cathode catalyst layer; The heat flow equilibrium of the microporous layer satisfies the following formula: ； In the formula: Ohmic heat for the microporous layer, For the thermal conductivity of the cathode catalyst layer and the microporous layer, For the microporous layer to conduct heat itself, For microporous layer convective heat; The heat flow equilibrium of the gas diffusion layer satisfies the following formula: ； In the formula: For the ohmic heat of the gas diffusion layer, For the thermal conductivity of the microporous layer, For the heat conduction of the gas diffusion layer, The heat generated is the convective heat of the gas diffusion layer; The heat flow balance of the channel layer satisfies the following formula: ； In the formula: To dissipate heat from the gas, For gas to enter the heat, For measuring heat convection in the channel; The heat flow balance of the bipolar plate layer satisfies the following formula: ； In the formula: For the ohmic heat of the bipolar plate layer, For the heat conduction of the gas diffusion layer, For the cooling heat of the bipolar plate, This is the convective heat of the bipolar plate.

5. The method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system according to claim 1, characterized in that, The thermal dynamics model satisfies the following formula: ； In the formula: It is the product of the heat capacity and mass of any one of the following: proton exchange membrane, anode and cathode catalyst layers, bipolar plate, gas diffusion layer, and microporous layer. i For an object value, T For temperature, t For time terms, Q It is for heat.

6. The method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system according to claim 1, characterized in that, The gas dynamics model satisfies the following formula: ； ； In the formula: t For time terms, This represents the number of moles of oxygen at the cathode. The subscripts "in" and "out" indicate the amount entering and exiting the fuel cell, respectively. This represents the number of moles of oxygen that actually occur during the electrochemical reaction. This represents the number of moles of hydrogen gas at the anode. This represents the number of moles of hydrogen gas during the actual electrochemical reaction. This represents the number of moles of nitrogen gas at the cathode. The number of moles of water, The number of moles of water produced during the electrochemical process; For cathode pressure, Let be the gas constant of air. The cathode temperature, Let V be the volume of the cathode. The mass of the gas entering the cathode, The mass of the gas leaving the cathode. Let be the gas constant of oxygen. The mass of oxygen reacted.

7. The method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system according to claim 6, characterized in that, The gas steady-state model satisfies the following formula: ； 。 8. The method for calculating the steady-state and dynamic multi-energy flow of a fuel cell power generation system according to claim 1, characterized in that, In S6, guiding the actual design includes: guiding the proton exchange membrane fuel cell system in the optimized design of fuel cell stack structure, design of air and hydrogen supply system, configuration and control parameter tuning of thermal management system, and formulation of system selection and power matching scheme.

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