Modeling method and prediction model of photovoltaic power generation and hydrogen storage system based on Simulink

Abstract

The present invention provides a modeling method and prediction model of a photovoltaic power generation hydrogen production and storage system based on Simulink, wherein the photovoltaic power generation hydrogen production and storage system comprises: a photovoltaic power generation module, a DC\DC buck converter module, an electrolyzer equivalent model module, and a hydrogen storage module; the positive and negative poles of the output voltage of the photovoltaic power generation module are connected to the positive and negative poles of the input end of the DC\DC buck converter module, and the positive and negative poles of the output end of the DC\DC buck converter module are connected to the positive and negative poles of the electrolyzer equivalent model module; the current i flowing through the electrolyzer is connected to the hydrogen storage module. The system of the present invention comprises a photovoltaic power generation module, a DC\DC buck converter module, an electrolyzer equivalent model module, and a hydrogen storage module. The system model constructed by the modeling method can predict the amount of hydrogen produced according to weather conditions, and the prediction result is accurate. The system can be applied to photovoltaic hydrogen production projects to predict the amount of hydrogen produced, guide engineering practice, and reduce costs.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production and storage technology, and more particularly to a Simulink modeling method and prediction model for a photovoltaic power generation hydrogen production and storage system. Background Technology

[0002] With economic development and continuous advancements in science and technology, fossil fuel reserves can no longer meet the needs of human development. Furthermore, the extensive use of fossil fuels has exacerbated global environmental pollution. Therefore, there is an urgent need to develop renewable energy to improve the current situation. Renewable energy power generation is highly dependent on weather conditions; photovoltaic power generation exhibits significant diurnal and daytime variations, resulting in an unstable power generation curve. Direct grid connection would increase the burden on grid regulation and, in severe cases, cause grid instability, impacting power security. This leads to (i) power system instability due to the volatility of these energy sources; and (ii) a mismatch between supply and demand. Therefore, energy storage systems are becoming increasingly important, and hybrid renewable energy systems combining elements such as hydrogen and solar energy are receiving increasing attention. However, a major problem with renewable energy is the uninterrupted storage of energy. Scholars have conducted detailed analyses of different energy storage technologies (pumped hydro storage, compressed air storage, batteries, etc.). Due to its clean and efficient characteristics, hydrogen energy appears to be one of the most promising solutions for storing surplus renewable energy. Compared to chemical energy storage, hydrogen production using photovoltaics is less expensive and can achieve energy storage across days, weeks, and quarters. Alternatively, hydrogen can be compressed or liquefied for long-distance transportation, aligning with both power generation and user needs. Therefore, hydrogen is currently considered a key technology for the sustainable, large-scale, and long-term storage of green renewable energy.

[0003] However, as a new energy technology, photovoltaic hydrogen production and storage has a relatively short development history in my country, and there is still a long way to go from development to practical application. Therefore, it is necessary to propose a modeling method and prediction model for photovoltaic hydrogen production and storage systems based on Simulink. This modeling method can also simulate and predict actual photovoltaic hydrogen production projects, reducing the time from research and development to implementation and lowering engineering costs.

[0004] Matlab / Simulink offers built-in solar panel and electrolyzer modules, but these models cannot be customized to meet diverse customer requirements. Furthermore, existing systems cannot achieve integrated solar-powered hydrogen production and storage. Conversely, they cannot optimize the system based on the required hydrogen quantity to achieve optimal energy utilization. Therefore, this paper proposes a modeling method and prediction model for a photovoltaic hydrogen production and storage system based on Simulink. The model uses basic modules to construct solar panel and electrolyzer models, allowing for parameter modification based on actual conditions.

[0005] A literature search of existing technologies revealed that Chinese invention patent CN 112953021 A discloses a renewable energy hydrogen production system and its control method. This patent proposes a scheme for coupling the hydrogen production system with a renewable energy power generation system, as well as a control method for the renewable energy hydrogen production system, thereby improving hydrogen production efficiency. However, this patent does not achieve integrated photovoltaic hydrogen production and storage. Therefore, this patent's renewable energy hydrogen production system mainly focuses on the hydrogen production system and its control method, with less attention paid to aspects of the hydrogen storage system. Summary of the Invention

[0006] In response to the technical problems mentioned in the background section, this invention proposes a modeling method and prediction model for a Simulink-based photovoltaic hydrogen production and storage system. This model simulates the relationship between light intensity and temperature and hydrogen production and storage. By comprehensively evaluating weather conditions provided by meteorological stations and the required hydrogen quantity, the most suitable photovoltaic array is selected for operation, avoiding resource waste and saving costs. Furthermore, this modeling method can also simulate and predict actual photovoltaic hydrogen production projects, reducing the time from research and development to implementation and lowering engineering costs.

[0007] The technical means employed in this invention are as follows:

[0008] A modeling method and prediction model for a photovoltaic power generation and hydrogen storage system based on Simulink are characterized in that the photovoltaic power generation and hydrogen storage system includes: a photovoltaic power generation module, a DC / DC buck converter module, an electrolyzer equivalent model module, and a hydrogen storage module; the positive and negative terminals of the output voltage of the photovoltaic power generation module are connected to the positive and negative terminals of the input terminals of the DC / DC buck converter module, and the positive and negative terminals of the output terminals of the DC / DC buck converter module are connected to the positive and negative terminals of the electrolyzer equivalent model module; the current i flowing through the electrolyzer is connected to the hydrogen storage module;

[0009] When the input light intensity and temperature are measured, the solar panel generates voltage, which fluctuates. Therefore, a capacitor is connected in parallel across the output voltage terminals of the solar panel. Since the electrolyzer requires high current and low voltage during operation, the DC / DC step-down converter reduces the output voltage of the solar panel and proportionally increases the current to ensure normal operation of the electrolyzer. The current flowing through the electrolyzer allows calculation of the hydrogen gas flow rate, which in turn calculates the pressure in the hydrogen storage tank. The pressure in the hydrogen storage tank determines whether it is full. When the pressure reaches a set value, the next hydrogen storage tank is used for hydrogen storage.

[0010] Compared with the prior art, the present invention has the following advantages:

[0011] 1. This system includes a photovoltaic power generation module, a DC / DC step-down converter module, an equivalent model module for an electrolyzer, and a hydrogen storage module. The system model constructed using this modeling method can accurately predict hydrogen production based on weather conditions. This system can be applied to photovoltaic hydrogen production projects, predicting hydrogen production levels, guiding engineering practice, and reducing costs.

[0012] 2. An equivalent model of an electrolyzer is used to replace the electrolyzer connection circuit, enabling the electricity generated by the photovoltaic device to be used to power the electrolyzer through a DC / DC step-down converter. This prediction model has good accuracy and stability, realizing the integration of solar-powered hydrogen production and storage.

[0013] 3. A modeling method and prediction model for a photovoltaic power generation and hydrogen storage system based on Simulink is of great significance for simulating photovoltaic hydrogen production and storage. It can determine the required number of photovoltaic devices based on the expected amount of hydrogen produced, thereby achieving optimal energy utilization. Attached Figure Description

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

[0015] Figure 1 This is the equivalent circuit of the solar panel in this invention.

[0016] Figure 2 This is the equivalent circuit diagram of the DC / DC converter of the present invention.

[0017] Figure 3 This is a schematic diagram of the MATLAB / Simulink model of the photovoltaic electrolysis hydrogen production and storage system of the present invention.

[0018] Figure 4 This is a schematic diagram of the MATLAB / Simulink model of the solar panel of the present invention.

[0019] Figure 5 This is a schematic diagram of the MATLAB / Simulink model of the electrolytic cell of the present invention.

[0020] Figure 6 This is a schematic diagram of the MATLAB / Simulink model of the hydrogen storage model of this invention.

[0021] Figure 7This is a data fitting graph of the self-built model and the built-in model of this invention; where a is the PV curve and b is the IV curve.

[0022] Figure 8 This is a graph showing the change of light intensity over time according to the present invention.

[0023] Figure 9 This is a graph showing the change in output power of the solar panel of this invention with light intensity.

[0024] Figure 10 This is a graph showing the variation of the output power of the electrolytic cell of the present invention with light intensity.

[0025] Figure 11 This is a schematic diagram of Example 1 of the present invention.

[0026] Figure 12 This is a schematic diagram of Example 2 of the present invention. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] like Figure 1-12As shown, this invention provides a modeling method and prediction model for a photovoltaic power generation and hydrogen storage system based on Simulink. The photovoltaic power generation and hydrogen storage system comprises: a photovoltaic power generation module, a DC / DC step-down converter module, an electrolyzer equivalent model module, and a hydrogen storage module; the positive and negative terminals of the output voltage of the photovoltaic power generation module are connected to the positive and negative terminals of the input terminals of the DC / DC step-down converter module, and the positive and negative terminals of the output terminals of the DC / DC step-down converter module are connected to the positive and negative terminals of the electrolyzer equivalent model module; the current i flowing through the electrolyzer is connected to the hydrogen storage module.

[0030] When the input light intensity and temperature are measured, the solar panel generates voltage, which fluctuates. Therefore, a capacitor is connected in parallel across the output voltage terminals of the solar panel. Since the electrolyzer requires high current and low voltage during operation, the DC / DC step-down converter reduces the output voltage of the solar panel and proportionally increases the current to ensure normal operation of the electrolyzer. The current flowing through the electrolyzer allows calculation of the hydrogen gas flow rate, which in turn calculates the pressure in the hydrogen storage tank. The pressure in the hydrogen storage tank determines whether it is full. When the pressure reaches a set value, the next hydrogen storage tank is used for hydrogen storage.

[0031] In a preferred embodiment, the modeling steps for the photovoltaic power generation module in this application are as follows:

[0032] Step S1: Build a model in Simulink according to formulas (1) to (7), where the maximum power point voltage and current, open circuit voltage, and short circuit current are provided by the manufacturer of the selected Trina Solar TSM-250PA05.08 solar panel.

[0033] Formulas (1) to (3) are used when the light intensity is 1000 W / m 2 The formula is valid under an environmental condition of 25℃, but it is far from the actual working environment of the solar panel. Therefore, formulas (4) to (7) are used to correct the error according to the actual environmental conditions. A photovoltaic power generation model is established according to formulas (1) to (7), and the light intensity and temperature are input to obtain the output current and voltage of the solar panel.

[0034] I PV =I SC [1-C1(expU PV / C2U OC -1)]; (1)

[0035] C1 = exp(-U m / C2U OC (1-I) m / I sc (2)

[0036] C2=(U m / U OC -1) / [ln(1-I m / I sc (3)

[0037] ΔT=TT ref (4)

[0038] ΔG=G / G ref -1; (5)

[0039] I' SC =I SC G / G ref (1+aΔT); (6)

[0040] U' OC =U OC ln(e+bΔG)(1-cΔT); (7)

[0041] Among them, I pv I represents the output current of the solar panel. sc U represents the short-circuit current. oc U represents the open-circuit voltage. m I represents the voltage at maximum power. m I' represents the current at maximum power. SC U' represents the short-circuit current that varies with environmental conditions. OC This represents the open-circuit voltage as the environment changes, where a, b, and c are all empirical constants.

[0042] Based on the above formulas, establish C1, C2, and I' for the photovoltaic power generation module respectively. SC 、U' OC Four sub-modules; the output of module C2 is connected to the input of module C1, and the light intensity and temperature are respectively I' SC 、U' OC The module's input terminals are connected; C1, I' SC 、U' OC The outputs of U and U are connected to the input terminals of the Ipv module, forming a photovoltaic power generation module.

[0043] In a preferred embodiment, the DC / DC buck converter module includes an IGBT, a diode, an inductor, a capacitor, and a resistor.

[0044] The diode, capacitor, and resistor are connected in parallel, the IGBT is connected in series between the input voltage of the solar panel and the diode, and the inductor is connected in series between the diode and the capacitor; wherein, the pulse width modulation signal of the IGBT is controlled by maximum power point tracking based on the perturbation-observation method.

[0045] In this embodiment, the equivalent model module of the electrolytic cell is equivalent to a resistor; the equivalent model module of the electrolytic cell can be regarded as a nonlinear resistor during the reaction process, which is related to the chemical properties of the solution, the pressure and temperature of the reaction, and is expressed as follows:

[0046]

[0047] Among them, R e It is the equivalent resistance of the electrolytic cell, R. eo α is the initial resistance, and β represents empirical constants.

[0048] Preferably, the modeling steps of the electrolytic cell equivalent model module are as follows: the positive and negative terminals of the voltage measurement module are connected to the positive and negative electrode modules respectively; the current output by the positive and negative electrode modules is connected to the multiplication input terminal of the division module; the first constant module is connected to the division input terminal of the division module; the output terminal of the division module is connected to the input terminals of the squaring module and the first multiplication module; the output terminal of the squaring module is connected to the input terminal of the first multiplication module; the output terminal of the first multiplication module is connected to the input terminal of the second multiplication module; the output terminal of the second constant module is connected to the input terminal of the second multiplication module; the output terminal of the second multiplication module is connected to the input terminal of the addition module; the output terminal of the third constant module is connected to the input terminal of the addition module; the output terminal of the addition module is connected to the input terminal of the third multiplication module; the output terminal of the fourth constant module is connected to the input terminal of the third multiplication module; the output terminal of the third multiplication module is connected to the input terminal of the controlled current source module. The positive and negative terminals of this module are connected to the negative and positive electrode modules respectively.

[0049] Preferably, the hydrogen storage module is represented by the internal pressure of the hydrogen cylinder; the more hydrogen flowing into the cylinder, the greater the pressure inside, as expressed by Formula 9:

[0050]

[0051] Among them, P b P represents the pressure of the hydrogen storage tank. bi The pressure of the hydrogen storage tank is represented by z, and the compressibility coefficient is represented by M. H2 T is the molar mass of hydrogen, R is the universal gas constant, and T is the molar mass of hydrogen. b Indicates operating temperature, V b This indicates the volume of the hydrogen storage cylinder.

[0052] Preferably, the modeling steps for the hydrogen storage module are as follows: the first, second, and third constant modules are connected to the multiplication input terminal of the division module; the fourth and fifth constant modules are connected to the division input terminal of the division module; the output terminal of the division module is connected to the input terminal of the integration module; the output terminal of the integration module is connected to the positive input terminal of the subtraction module; the sixth constant module is connected to the negative input terminal of the subtraction module. The output terminal of the subtraction module is connected to the output module.

[0053] Example 1

[0054] A Simulink-based photovoltaic hydrogen production and storage system includes a photovoltaic array, a DC / DC converter, an electrolyzer, and a hydrogen storage device. The electricity generated by the photovoltaic array is supplied to the electrolyzer via the DC / DC converter, and the hydrogen produced by the electrolyzer is stored in the hydrogen storage device. The system has a predictive function, which is implemented through the following steps:

[0055] 1. Obtain weather information for the next m days from a weather station, where m is a positive integer.

[0056] 2. Extract two parameters, light intensity and temperature, from the weather information for m days.

[0057] 3. By inputting the average daily light intensity and temperature over m days into the light intensity input port and temperature input port of the photovoltaic array, the daily hydrogen production can be predicted. Alternatively, by inputting the hourly light intensity and temperature, the hourly hydrogen production can be predicted.

[0058] 4. Arrange the number of hydrogen storage cylinders reasonably according to the amount of hydrogen produced.

[0059] Example 2

[0060] A photovoltaic (PV) hydrogen production and storage system includes a photovoltaic array, a DC / DC converter, an electrolyzer, and a hydrogen storage device. The PV array comprises multiple PV strings, the number of which can be determined based on weather conditions and the required hydrogen production volume. The DC / DC converter is determined by the number of PV strings, and each DC / DC converter is connected to at least one PV string. The electrolyzer can be a PEM electrolyzer or other types of electrolyzers. The hydrogen storage device is typically a hydrogen storage cylinder.

[0061] A photovoltaic power generation and hydrogen production and storage system includes the following steps:

[0062] 1. Obtain weather information for the next m days from a weather station, where m is a positive integer.

[0063] 2. Obtain the amount of hydrogen S required to be produced in the next m days.

[0064] 3. Collect data on light intensity and temperature every hour. Use the collected data as the average light intensity and temperature for that hour and import them into the system model to predict the amount of hydrogen S1 produced by a set of photovoltaic strings.

[0065] 4. Calculate n = S / S1, where n is the amount of hydrogen required for production and the number of photovoltaic strings needed under the weather conditions in the next few days, where n is a positive integer.

[0066] Example 3

[0067] To verify the accuracy of the model built using this method, a Trina SolarTSM-250PA05.08 solar panel was selected. The system's built-in solar panel module was chosen from the Simulink module library, and its characteristic curve was output. Simultaneously, a Simulink model of the solar panel was built based on four parameters: maximum power voltage and current, open-circuit voltage, and short-circuit current. The characteristic curves output by this model were compared with those output by the system's built-in model. Figure 7 As shown in (a) and (b), the established model can fit the PV and IV characteristic curves of the built-in model well, proving that the model has accuracy.

[0068] To verify the stability of the model built using this method, the temperature can be kept constant while the light intensity is changed, such as... Figure 8 As shown, the stability of this system is determined by the output of the solar panel and the electrolytic cell. Figure 9 It can be seen that when the solar panel is exposed to sunlight, it reaches its maximum power point under that light intensity after approximately 0.3 seconds. After two changes in light intensity, the solar panel's output power can reach and stabilize in response to these changes. Figure 10 As shown, the electrolytic cell exhibits a fluctuation time of approximately 0.2 seconds when the light intensity changes, which is within a reasonable and acceptable range.

[0069] After verifying the accuracy and stability of the model, it can be used to predict hydrogen production. By collecting data on light intensity and temperature every hour, and importing this data as the hourly average light intensity and temperature into the system model, the total hydrogen production for the day under the given weather conditions can be obtained, as well as the hydrogen production for each time period.

[0070] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0071] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. The modeling method and prediction model of photovoltaic power generation and hydrogen storage system based on Simulink is characterized by: The photovoltaic power generation hydrogen production and storage system comprises: a photovoltaic power generation module, a DC\DC buck converter module, an electrolyzer equivalent model module, and a hydrogen storage module; the positive and negative electrodes of the output voltage of the photovoltaic power generation module are connected to the positive and negative electrodes of the input end of the DC\DC buck converter module, and the positive and negative electrodes of the output end of the DC\DC buck converter module are connected to the positive and negative electrodes of the electrolyzer equivalent model module; the current i flowing through the electrolyzer is connected to the hydrogen storage module; When the light intensity and temperature are input, the solar panel can generate voltage, and the generated voltage will fluctuate. Therefore, a capacitor is connected in parallel at both ends of the output voltage of the solar panel. Since the electrolyzer requires high current and low voltage when working, the output voltage of the solar panel is reduced by the DC\DC buck converter, and the current is increased in the same proportion to meet the normal operation of the electrolyzer. The rate of hydrogen flowing through the electrolyzer is calculated, and the pressure of the hydrogen storage bottle is calculated by the rate of hydrogen. The pressure of the hydrogen storage bottle is used to determine whether the hydrogen storage bottle is full. When the pressure reaches the set value, the next hydrogen storage bottle will be replaced for hydrogen storage. The steps of modeling the photovoltaic power generation module are as follows: establishing a model in Simulink according to formulas (1) to (7), wherein the maximum power point voltage and current, and the open circuit voltage; Wherein, formulas (1) to (3) are based on the light intensity of 1000W / m 2 , which is established under the environmental condition of 25℃, but it is far from the actual working environment of the solar panel. Therefore, formulas (4) to (7) are used to correct according to the actual environmental conditions to reduce the error. According to formulas (1) to (7), a photovoltaic power generation model is established, and the light intensity and temperature are input to obtain the output current and voltage of the solar panel: I PV =I SC [1-C1(expU PV / C2U OC -1)];(1) C1=exp(-U m / C2U OC )(1-I m / I sc );(2) C2=(U m / U OC -1) / [ln(1-I m / I sc )];(3) ΔT=T-T ref ;(4) ΔG=G / G ref -1;(5) I' SC =I SC G / G ref (1+aΔT);(6) The OC =U OC ln(e+bΔG)(1-cΔT);(7) Among them, I pv Represents the output current of the solar panel, I sc Indicates short-circuit current, U oc Indicates the open circuit voltage, U m Indicates the voltage at maximum power, I m Indicates the current at maximum power, I' SC Indicates the short-circuit current that varies according to the environment, U' OC represents the open circuit voltage that changes according to the environment, and a, b, and c are all empirical constants; According to the above formula, the C1, C2, I' of the photovoltaic power generation module are established respectively. SC , U' OC Four submodules; the output of C2 module is connected to the input of C1 module, and the light intensity and temperature are I' SC , U' OC The input terminal of the module is connected to; C1, I' SC , U' OC The outputs of U and U are respectively connected to the input ends of the Ipv module to form a photovoltaic power generation module; the DC\DC buck converter module includes an IGBT, a diode, an inductor, a capacitor and a resistor; The diode, capacitor and resistor are connected in parallel, the IGBT is connected in series between the input voltage of the solar panel and the diode, and the inductor is connected in series between the diode and the capacitor.

2. The modeling method and prediction model of photovoltaic power generation and hydrogen storage system based on Simulink according to claim 1, characterized in that: The electrolytic cell equivalent model module is equivalent to a resistor; the electrolytic cell equivalent model module is regarded as a nonlinear resistor during the reaction process, which is related to the chemical properties of the solution, the pressure and temperature of the reaction, and is expressed as: Among them, R e is the equivalent resistance of the electrolytic cell, R eo is the initial resistance, and α and β are empirical constants.

3. The modeling method and prediction model of photovoltaic power generation and hydrogen storage system based on Simulink according to claim 2, characterized in that: The modeling steps of the electrolytic cell equivalent model module are as follows: the positive and negative signs of the voltage measurement module are respectively connected to the positive and negative electrode modules; the current output by the positive and negative electrode modules is connected to the multiplication input end of the division module; the first constant module is connected to the division input end of the division module; the output end of the division module is connected to the input end of the square module and the input end of the first multiplication module; the output end of the square module is connected to the input end of the first multiplication module; the output end of the first multiplication module is connected to the input end of the second multiplication module; the output end of the second constant module is connected to the input end of the second multiplication module; the output end of the second multiplication module is connected to the input end of the addition module; the output end of the third constant module is connected to the input end of the addition module; the output end of the addition module is connected to the input end of the third multiplication module, and the output end of the fourth constant module is connected to the input end of the third multiplication module; the output end of the third multiplication module is connected to the input end of the controlled current source module; the positive and negative signs of the module are respectively connected to the negative and positive electrode modules.

4. The modeling method and prediction model of photovoltaic power generation and hydrogen storage system based on Simulink according to claim 1, characterized in that: The hydrogen storage module is represented by the internal pressure of the hydrogen bottle. The more hydrogen flows into the bottle, the greater the pressure inside the bottle, which is represented by Formula 9: Among them, P b Indicates the pressure of the hydrogen storage bottle, P bi represents the pressure of the hydrogen storage bottle, z represents the compression coefficient, M H2 is the molar mass of hydrogen, R is the universal gas constant, T b Indicates the operating temperature, V b Indicates the volume of the hydrogen storage bottle.

5. The modeling method and prediction model of photovoltaic power generation and hydrogen storage system based on Simulink according to claim 4, characterized in that: The steps of modeling the hydrogen storage module are as follows: the first, second and third constant modules are respectively connected to the multiplication input terminal of the division module; the fourth and fifth constant modules are connected to the division input terminal of the division module; the output terminal of the division module is connected to the input terminal of the integration module; the output terminal of the integration module is connected to the positive input terminal of the subtraction module; The sixth constant module is connected to the minus input terminal of the subtraction module; and the output terminal of the subtraction module is connected to the output module.

Images