Hydrogen absorption method and system of solid hydrogen storage device considering green hydrogen yield fluctuation characteristics

Abstract

The invention discloses a hydrogen absorption method and system of a solid hydrogen storage device taking green hydrogen yield fluctuation characteristics into consideration, and belongs to the technical field of hydrogen energy storage. According to the method, a green hydrogen flow dynamic distribution algorithm is provided for a hydrogen storage system composed of a plurality of hydrogen storage reactors so as to automatically select a proper hydrogen storage reactor. By analyzing green hydrogen yields at different time points and hydrogen absorption rates, hydrogen storage amounts and hydrogen storage depths of related hydrogen storage reactors in hydrogen storage devices at corresponding time points, green hydrogen production speeds are matched with hydrogen absorption rates of the hydrogen storage devices, and the hydrogen absorption rates can meet distribution amounts; according to the dynamic green hydrogen storage strategy, the green hydrogen storage efficiency is improved, the energy consumption is reduced, meanwhile, the hydrogen storage device can cope with the fluctuation of large-scale green hydrogen production, and a new thought is provided for effective utilization of hydrogen converted from renewable energy.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen energy storage, and specifically relates to a hydrogen absorption method and system for a solid-state hydrogen storage device that takes into account the fluctuation characteristics of green hydrogen production. Background Art

[0002] As a key driver of global energy transformation, hydrogen energy utilizes renewable energy sources such as wind and photovoltaics to produce hydrogen through water electrolysis, providing large quantities of green hydrogen. This significantly increases renewable energy consumption capacity and reduces energy consumption and carbon emissions. However, the volatility of renewable energy power makes it difficult to adapt to the stability requirements of traditional production processes. Consequently, hydrogen storage and transportation remain a key bottleneck restricting hydrogen energy utilization.

[0003] Solid-state hydrogen storage materials offer high hydrogen storage density and excellent cycling characteristics, leading to the application of solid-state hydrogen storage technology to the storage of fluctuating green hydrogen. However, due to the strong thermal effects of solid-state hydrogen absorption and desorption, which limit the capacity of hydrogen storage reactors, and the fluctuations in green hydrogen levels, which limit the hydrogen absorption rate of reactors, the development of reasonable large-scale hydrogen absorption methods is urgently needed. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a hydrogen absorption method for a solid-state hydrogen storage device that takes into account the fluctuation characteristics of green hydrogen production, so as to solve the problem of difficulty in hydrogen absorption caused by green hydrogen fluctuation in the prior art.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A hydrogen absorption method for a solid-state hydrogen storage device taking into account the fluctuation characteristics of green hydrogen production includes the following steps: S1, dividing the set time period into time intervals, and obtaining the variation pattern of renewable energy power generation within the set time period; S2: Construct the relationship between the average hydrogen absorption rate of a single hydrogen storage reactor and the hydrogen storage depth, and establish a hydrogen absorption rate model for a single hydrogen storage reactor; based on the variation pattern of renewable energy power generation, determine the number of hydrogen storage reactors that can meet the hydrogen storage demand within a set time period, and multiple hydrogen storage reactors form a hydrogen storage system; S3, allocating hydrogen flow to multiple hydrogen storage reactors under constraints in time intervals; giving priority to reactors with low hydrogen storage depths during peak periods, and giving priority to reactors with high hydrogen storage depths during off-peak periods; S4, determining whether the average hydrogen absorption rate of a single hydrogen storage reactor can meet the allocated hydrogen flow rate when executing the allocation method in S3 within the time interval, and if not, adjusting the allocated hydrogen flow rate of the hydrogen storage reactor; S5, repeat S3 and S4 until the average hydrogen absorption rate of each hydrogen storage reactor in each time interval can meet the corresponding hydrogen production, and the hydrogen absorption of the entire hydrogen storage system can meet all hydrogen production in the set time period. If satisfied, the allocation ends; if not satisfied, adjust the number of hydrogen storage reactors and repeat S2-S4.

[0006] A further improvement of the present invention is: Preferably, in S1, the time interval is obtained by dividing the set time period into equal intervals.

[0007] Preferably, in S2, the relationship between the hydrogen absorption rate and the hydrogen storage depth is: (3) (4) Where, is the hydrogen storage depth; is the amount of hydrogen absorbed by the metal hydride, kg; is the total amount of hydrogen stored per hydrogen storage reactor, kg; It is the time change quantity, which has the same unit as the green hydrogen fluctuation and is based on hours; is the change in hydrogen storage capacity corresponding to time change, kg; is the hydrogen absorption rate, kg / h.

[0008] Preferably, in S2, the formula for determining the number of hydrogen storage reactors that can meet the hydrogen storage demand within the set time period is: (10) Where, Number of solid-state hydrogen storage reactors, units; is the daily green hydrogen production of the electrolyzer, kg.

[0009] Preferably, in S3, the constraint condition is: (11) (12) (13) Where, For the k The amount of hydrogen flow allocated in the green hydrogen production during the time period, kg / h; For the k -1 The hydrogen storage capacity of the reactor at the end of the time period, kg; For the k -1 The average hydrogen absorption rate of the reactor during the time period.

[0010] Preferably, in S5, during the process of repeating S3 and S4, the average hydrogen storage absorption rate of the hydrogen storage reactor is updated for different time intervals: (17) Where, For this allocation i Average rate per reactor, kg / h, For the k At the end of the time period i The hydrogen storage depth of each reactor.

[0011] Preferably, the hydrogen storage depth is updated at different time intervals, and the updating formula is: (14) (15) (16) Where, For the k At the end of the time period i Hydrogen storage capacity of each reactor, kg; For the k At the end of the time period i The hydrogen storage depth of each reactor.

[0012] Preferably, in S5, the process of judging whether the average hydrogen absorption rate of the hydrogen storage reactor can meet the corresponding hydrogen production is: judging whether the average hydrogen absorption rate of the hydrogen storage reactor is greater than the allocated hydrogen flow rate, and if so, adjusting the allocated hydrogen flow rate.

[0013] Preferably, the set time period is 24 hours, and the time interval is 1 hour.

[0014] A hydrogen absorption device for a solid-state hydrogen storage device taking into account the fluctuation characteristics of green hydrogen production comprises: The time division module divides the set time period into time intervals, obtains the change pattern of renewable energy power generation within the set time period, and calculates the change pattern according to the change pattern; The model building module constructs the relationship between the average hydrogen absorption rate of a single hydrogen storage reactor and the hydrogen storage depth, and establishes a hydrogen absorption rate model for a single hydrogen storage reactor. Based on the variation pattern of renewable energy power generation, the number of hydrogen storage reactors that can meet the hydrogen storage demand within a set time period is determined, and multiple hydrogen storage reactors form a hydrogen storage system. The flow distribution module allocates hydrogen flow to multiple hydrogen storage reactors based on time intervals and constraints. During peak periods, reactors with low hydrogen storage depths are given priority, while during off-peak periods, reactors with high hydrogen storage depths are given priority. The flow rate judgment module judges whether the average hydrogen absorption rate of a single hydrogen storage reactor can meet the allocated hydrogen flow rate when executing the allocation method of the flow allocation module within the time interval. If not, adjust the allocated hydrogen flow rate of the hydrogen storage reactor; The flow adjustment module repeats the flow allocation module and the flow judgment module until the average hydrogen absorption rate of each hydrogen storage reactor in each time interval can meet the corresponding hydrogen production, and the hydrogen absorption of the entire hydrogen storage system can meet all hydrogen production in the set time period. If it is met, the allocation ends; if it is not met, the number of hydrogen storage reactors is adjusted, and the model construction module, flow allocation module and flow judgment module are repeated.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a hydrogen absorption method for a solid-state hydrogen storage device that takes into account the fluctuating characteristics of green hydrogen production. This method proposes a dynamic green hydrogen flow allocation algorithm for a hydrogen storage device composed of multiple hydrogen storage reactors to automatically select the appropriate hydrogen storage reactor. By analyzing the green hydrogen production at different time points and the hydrogen absorption rate, hydrogen storage capacity, and hydrogen storage depth of the relevant hydrogen storage reactors in the hydrogen storage device at the corresponding time points, and by matching the green hydrogen production rate with the hydrogen absorption rate of the hydrogen storage device, a distribution method is selected in which the hydrogen absorption rate meets the allocation amount. Reactors with lower hydrogen storage depths store less hydrogen and therefore can receive more hydrogen. Furthermore, when the hydrogen storage depth is low, the hydrogen absorption rate is higher to meet peak demand. The priority order and hydrogen absorption capacity of the reactors are determined, ultimately obtaining a dynamic green hydrogen storage strategy for the hydrogen storage device. This allocation method ensures that reactors with lower hydrogen absorption rates are used during off-peak periods, resulting in more stable system operation. The dynamic green hydrogen storage strategy not only improves green hydrogen storage efficiency and saves energy, but also enables hydrogen storage devices to cope with the volatility of large-scale green hydrogen production, providing a new approach for the effective utilization of renewable energy conversion into hydrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a process flow chart of the present invention; Figure 2 It is a diagram of the dynamic allocation algorithm of the present invention; Figure 3 This is a graph of green hydrogen production according to Example 1 of the present invention; Figure 4 This is a hydrogen absorption rate diagram of the hydrogen storage reactor of Example 1 of the present invention; Figure 5 This is a diagram of hydrogen distribution results of Example 1 of the present invention; Figure 6 This is a diagram of the hydrogen absorption rate of the hydrogen storage device of Example 1 of the present invention. DETAILED DESCRIPTION

[0017] The present invention is described in further detail below with reference to the accompanying drawings: The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0018] See also Figure 1 As the problem raised in the background technology, due to the large volatility of renewable energy power, the amount of hydrogen generated in the storage and transportation of hydrogen will fluctuate, which brings certain difficulties to the storage of hydrogen in solid-state hydrogen storage devices.

[0019] In order to solve the above problems, the present invention discloses a hydrogen absorption method for a solid-state hydrogen storage device taking into account the fluctuation characteristics of green hydrogen production. The method specifically comprises the following steps: S1, according to the set time period, obtain the renewable energy power generation power within the set time period, divide the set time period into a number of equally spaced time intervals; use the time interval as a unit to obtain the change pattern of the renewable energy power generation power within the set time period; supply the renewable energy power to the electrolytic cell to electrolyze water to produce hydrogen, and obtain the hydrogen production in different time intervals.

[0020] Furthermore, the overall allocation problem is divided into sub-problems that proceed over time. The power data in S1 is divided using a power threshold. The power threshold is the median of the output power of the group of renewable energy sources. The time interval when the power is greater than the power threshold is the peak period of green hydrogen supply, and the time interval when the power is less than the power threshold is the low-peak period of green hydrogen supply.

[0021] S2: Due to the limitations of heat and mass transfer in hydrogen storage reactors and the need for large-scale green hydrogen storage, large-scale hydrogen storage reactors are used. When determining the number and capacity of large hydrogen storage reactors, a model is established to determine the relationship between hydrogen absorption rate and absorption depth based on the hydrogen absorption characteristics of the reactors. This analysis analyzes the absorption rate characteristics and devises a method to obtain the average hydrogen absorption rate within a specified time interval. By coordinating the hydrogen storage depths of different reactors, the overall hydrogen absorption rate of the hydrogen storage device is coordinated to match the hydrogen supply rate.

[0022] The process of establishing the relationship model between hydrogen absorption rate and hydrogen absorption depth of hydrogen storage reactor is as follows: S21, construct the capacity and rate relationship of a single reactor To ensure coordination between different hydrogen storage units and adapt to the fluctuating demand for green hydrogen, the relationship between the hydrogen absorption rate of a single reactor and the temperature, pressure and hydrogen storage depth is established. The hydrogen capacity of the hydrogen storage reactor is set to be fixed, and the relationship between the capacity and the mass of the metal hydride is: (1) (2) Where, is the amount of hydrogen absorbed by the metal hydride, kg; is the mass fraction of hydrogen in the metal hydride; is the mass of metal hydride, kg; is the total amount of hydrogen stored per hydrogen storage reactor, kg; is the mass fraction of hydrogen after the reactor is fully filled with hydrogen.

[0023] Set hydrogen storage depth, describe hydrogen storage process, and establish rate-depth relationship (3) (4) Where, is the hydrogen storage depth; It is the time change quantity, which has the same unit as the green hydrogen fluctuation and is based on hours; is the change in hydrogen storage capacity corresponding to time change, kg; is the hydrogen absorption rate, kg / h.

[0024] Based on the kinetic equation of the metal hydrogenation process obtained in the experiment, the relationship between the hydrogen absorption rate and temperature, pressure and hydrogen storage depth can be obtained, the approximate relationship can be fitted, and a hydrogen absorption rate model can be established to dynamically calculate the hydrogen absorption rate according to different metal hydrides and different operating conditions.

[0025] S22, average reaction rate calculation Since the hydrogen storage depth changes over time during the hydrogen storage process, and the renewable energy fluctuation is based on an hourly basis, the average rate is needed to evaluate the carrying capacity of the hydrogen storage reactor per unit time period, and the rate relationship needs to be integrated (5) Where, Hydrogen storage depth arrive Average hydrogen absorption rate between, kg / h; is the relationship between depth and rate obtained by experimental fitting.

[0026] According to the relationship between depth change and rate, the hydrogen storage depth and current rate of the reactor can be dynamically adjusted.

[0027] S23, Green Hydrogen Production Model with Renewable Energy Taking the fluctuation of renewable energy as the hourly basis, the daily fluctuation of green hydrogen is divided into 24 intervals. Using a conventional alkaline electrolyzer to output green hydrogen, since the equivalent energy content of hydrogen is 39.4 kWh / kg, assuming the efficiency of alkaline electrolysis is 70%, the actual specific energy consumption is about 56.3 kWh / kg H2; the hydrogen flow rate output by the electrolyzer is: (6) (7) (8) Where, For the k Input power of electrolyzer during time period, kW; The amount of electricity consumed by the electrolyzer to produce 1 kg of hydrogen is 56.3 kWh; is the total flow rate of hydrogen generated by the electrolyzer during time period k and entering the hydrogen storage system, kg / h; The kth time period i Hydrogen distribution flow rate per reactor, kg / h; is the daily green hydrogen production of the electrolyzer, kg. In order to evaluate the volatility of renewable energy, the power threshold of the decision relationship is adopted (9) Where, is the median output power of renewable energy, kW.

[0028] S24, capacity requirements of hydrogen storage system The capacity of the hydrogen storage system must meet the daily production demand of green hydrogen (10) Where, Number of solid-state hydrogen storage reactors, pieces.

[0029] Based on the changing patterns of renewable energy generation in S1 and the green hydrogen supply data in S1, hydrogen storage capacity requirements are analyzed. A corresponding hydrogen storage system is established, and the number of hydrogen storage reactors within the system is determined based on the hydrogen storage capacity requirements. The number of hydrogen storage reactors in this hydrogen storage system must meet the requirements for dynamic allocation within each time interval and also meet the storage requirements for all green hydrogen generated by renewable energy within the set time period.

[0030] S3, divide the total allocation problem into sub-problems with time intervals. According to the green hydrogen supply in each time interval, the time interval is divided into peak period and non-peak period. The remaining capacity of the reactor in the current interval device and the hydrogen storage depth and hydrogen absorption rate of each reactor are analyzed to ensure that the hydrogen storage depth of the reactor cannot be greater than 1. During the peak period, the reactors are arranged in descending order of hydrogen absorption rate, and during the non-peak period, the reactors are arranged in ascending order of hydrogen absorption rate, and the hydrogen is distributed in sequence.

[0031] It should be noted that the hydrogen storage depth is defined as the depth of hydrogen stored in the hydrogen storage reactor, such as Figure 4 As shown in Figure (b), the greater the hydrogen storage capacity, the deeper the hydrogen storage depth, indicating that the portion of the reaction vessel that can store hydrogen is reduced. For any hydrogen storage reactor, its hydrogen absorption rate gradually decreases over time, as shown in Figure (b). Figure 4 As shown in Figure (a), the slope of the blue curve gradually slows down, indicating that as the amount of hydrogen absorbed increases, the hydrogen absorption capacity of the hydrogen storage reactor gradually decreases.

[0032] In this step, an algorithm for dynamically selecting reactors and allocating hydrogen flow is designed. The dynamic allocation algorithm is used as Figure 2 , v is the hydrogen absorption rate, f is the hydrogen flow rate, F is the total hydrogen production, X is the hydrogen storage depth, C is the hydrogen storage capacity, k is the kth time period, and i is the i-th reactor. Based on the hydrogen demand and reactor performance, the capacity demand is prioritized. The carrying capacity of the reactors in the current period is sorted. During peak periods, reactors with lower hydrogen storage depths are given priority for hydrogen distribution, while reactors with higher hydrogen storage depths are given priority during non-peak periods. During peak periods, reactors with higher hydrogen absorption rates are given priority, and it is judged whether the reactor rate can be met under different allocations. If it cannot be met, the reactor allocation amount is gradually reduced according to the rate until the hydrogen absorption rate is met. This algorithm can make the low hydrogen absorption rate close to the hydrogen production rate, avoid reactor idling, and maximize the rate redundancy of the hydrogen storage system during peak periods. This algorithm can achieve a dynamic response to the volatility of renewable energy and effectively deal with the uncertainty and variability in the system.

[0033] This allocation method has a large redundancy in hydrogen absorption rate during the peak period of green hydrogen supply, which improves the flexibility potential of the device. The green hydrogen supply is adjusted according to each time interval, and the remaining capacity of the reactor in the device and the hydrogen storage depth and hydrogen absorption rate of each reactor in the current period are analyzed. The hydrogen storage depth of the reactor is limited to no more than 1, and the allocation amount is limited to no more than the hydrogen absorption rate of the reactor in the previous period, and hydrogen is distributed to the reactor. The specific allocation process includes the following steps S31, allocation of hydrogen flow constraints First, the distribution flow cannot exceed the maximum capacity of the reactor. The reaction rate generally decreases with the increase of hydrogen storage depth, so the distribution flow cannot exceed the reaction rate of the reactor in the previous time period. Therefore, the constraint condition is (11) (12) (13) Where, For the k The amount of hydrogen flow allocated in the green hydrogen production during the time period, kg / h; For the k -1 The hydrogen storage capacity of the reactor at the end of the time period, kg; For the k -1 The average hydrogen absorption rate of the reactor during the time period.

[0034] The hydrogen flow rate is allocated to the reactor only when the above constraints are met.

[0035] S32, update hydrogen absorption rate according to hydrogen storage depth Since the hydrogen absorption rate decreases with depth, it is not possible to determine whether the hydrogen absorption capacity can be met based on the rate in the previous time period. Therefore, the hydrogen storage depth of the corresponding reactor is updated according to the allocated hydrogen flow rate. (14) (15) (16) Where, For the k At the end of the time period i Hydrogen storage capacity of each reactor, kg; For the k At the end of the time period i The hydrogen storage depth of each reactor.

[0036] According to the update of hydrogen storage depth, calculate the average hydrogen storage rate of the reactor during this period under the current allocation (17) Where, For this allocation i Average rate per reactor, kg / h.

[0037] S4, judging the rationality of allocation Analyze the hydrogen storage reactor under the hydrogen distribution strategy in S3 after the hydrogen storage depth changes, and integrate to obtain the average hydrogen absorption rate at the hydrogen storage depth to determine whether the average hydrogen absorption rate of the hydrogen storage reactor can meet the allocated hydrogen volume. If not, the reactor allocation amount is reduced to the amount of hydrogen absorbed by the reactor at the hydrogen absorption rate. The hydrogen absorption rate decreases with the hydrogen storage depth. If the allocation amount is reduced, the average hydrogen absorption rate will increase, making it easier to meet the allocation.

[0038] Determine the hydrogen absorption rate and hydrogen flow rate of the hydrogen storage reactor to which the hydrogen flow rate is allocated: (18) If satisfied, allocate hydrogen flow according to the assumed situation. k The time period allocation is completed. If it is not satisfied, it will be redistributed so that the allocation amount of the reactor that does not meet the conditions is less than the updated rate. (19) Redistribute the hydrogen flow and update the reaction hydrogen storage depth and hydrogen storage rate again until all called reactors meet , end the cycle, distribute the hydrogen flow, and enter the next time period.

[0039] In this way, the overall allocation problem is divided into sub-problems over time. When solving the sub-problems, under a gradually approaching cycle, the hydrogen absorption rate of the hydrogen storage system in that period meets the demand, and at the same time, the hydrogen absorption rate of the reactor is closest to the green hydrogen supply rate, so as to achieve the matching of the two systems, ensure that the reactor rate in the subsequent time period has a large redundancy, minimize the demand for the number of reactor operations, make the maximum use of each hydrogen storage unit, and complete the coordinated control strategy.

[0040] S6, repeat S3 and S4 until all time intervals within the set time period are allocated. During the allocation process, the hydrogen absorption rate of each hydrogen storage reactor in a time interval can meet the green hydrogen allocation amount, and the green hydrogen allocation method for this time period is obtained. If it cannot be met after traversing all reactors, the number of reactors is increased.

[0041] The above-mentioned S4 and S5 processes are aimed at a method for allocating hydrogen flow to each hydrogen storage reactor in a hydrogen storage system within a time interval. After the allocation of each hydrogen storage reactor in a time interval is completed, the hydrogen flow allocation for the next time interval is carried out. After the hydrogen flow in each time interval is allocated and meets the requirements, the allocation is completed.

[0042] In some embodiments of the present invention, in step 1, when collecting the hydrogen production pattern, one day is used as a cycle. First, the change pattern of renewable energy power generation data is collected on an hourly basis, and then the daily fluctuation of green hydrogen is divided into 24 intervals over time; the electric power data that changes within 24 hours is supplied to the electrolyzer to electrolyze water to produce green hydrogen. Taking alkaline water electrolysis hydrogen production technology as an example, the equivalent energy content of hydrogen is 39.4 kWh / kg, the efficiency of the alkaline electrolyzer is 70%, and the actual specific energy consumption is about 56.3 kWh / kg H2, and the hydrogen production in different time intervals is obtained.

[0043] The renewable energy power data obtained in step 1 is fed into an electrolyzer to electrolyze water to produce green hydrogen. Taking alkaline water electrolysis hydrogen production technology as an example, the equivalent energy content of hydrogen is 39.4 kWh / kg, the efficiency of the alkaline electrolyzer is 70%, and the actual specific energy consumption is approximately 56.3 kWh / kg H2. The hydrogen production in different time intervals is obtained.

[0044] In step 2, taking the Mg-based hydrogen storage reactor as an example, 10 kg of MgH2 is generally loaded, and the maximum storage capacity is 8.45 Nm 3 For hydrogen, the hydrogen absorption rate is faster when the inlet temperature of the heat exchange fluid is 473.15~523.15 K. Based on the hydrogen absorption characteristics of the hydrogen storage reactor, a model of the relationship between the hydrogen absorption rate and the hydrogen absorption depth is established. The characteristics of the hydrogen absorption rate are analyzed, and a method is designed to obtain the average hydrogen absorption rate within a specified time interval.

[0045] It should be noted that the above time period can be adjusted according to actual needs, and the time intervals divided within the period can also be adjusted according to needs.

[0046] A second aspect of the present invention discloses a hydrogen absorption device of a solid-state hydrogen storage device that takes into account the fluctuation characteristics of green hydrogen production, comprising: The time division module divides the set time period into time intervals, obtains the change pattern of renewable energy power generation within the set time period, and calculates the change pattern according to the change pattern; The model building module constructs the relationship between the average hydrogen absorption rate of a single hydrogen storage reactor and the hydrogen storage depth, and establishes a hydrogen absorption rate model for a single hydrogen storage reactor. Based on the variation pattern of renewable energy power generation, the number of hydrogen storage reactors that can meet the hydrogen storage demand within a set time period is determined, and multiple hydrogen storage reactors form a hydrogen storage system. The flow distribution module allocates hydrogen flow to multiple hydrogen storage reactors based on time intervals and constraints. During peak periods, reactors with low hydrogen storage depths are given priority, while during off-peak periods, reactors with high hydrogen storage depths are given priority. The flow rate judgment module judges whether the average hydrogen absorption rate of a single hydrogen storage reactor can meet the allocated hydrogen flow rate when executing the allocation method of the flow allocation module within the time interval. If not, adjust the allocated hydrogen flow rate of the hydrogen storage reactor; The flow adjustment module repeats the flow allocation module and the flow judgment module until the average hydrogen absorption rate of each hydrogen storage reactor in each time interval can meet the corresponding hydrogen production, and the hydrogen absorption of the entire hydrogen storage system can meet all hydrogen production in the set time period. If it is met, the allocation ends; if it is not met, the number of hydrogen storage reactors is adjusted, and the model construction module, flow allocation module and flow judgment module are repeated.

[0047] The following is further described with reference to specific embodiments.

[0048] Example 1 This is illustrated by using a typical summer day photovoltaic power generation data and hydrogen absorption data of a large Mg-based hydrogen storage reactor predicted in a certain place in 2021 based on the multi-scale fluctuation feature extraction method, using an alkaline electrolyzer.

[0049] (1) After calculating and allocating the power generation data, the daily output of green hydrogen from photovoltaic power generation is 9.398 kg, the power threshold is 46.28 kW, and the time period from 10:00 to 16:00 is the peak period of green hydrogen output. The green hydrogen output in the 13 time intervals is as follows: Figure 3 .

[0050] (2) The collected hydrogen storage kinetic data of the 10 kg-level Mg-based hydrogen storage reactor were calculated and fitted to obtain the relationship between the reactor hydrogen absorption rate and hydrogen storage depth as follows: Figure 4 The hydrogen absorption rate first drops sharply with the hydrogen storage depth, and then decreases slowly.

[0051] (3) The hydrogen allocation results of the dynamic allocation strategy are as follows: Figure 5 The hydrogen storage depth and hydrogen absorption rate of different reactors are dynamically monitored and controlled to automatically adjust the green hydrogen distribution of different reactors. The results show that the solid-state hydrogen storage device consisting of 13 10 kg-level MgH2 hydrogen storage reactors can meet the daily green hydrogen production of the green hydrogen device and achieve a green hydrogen utilization rate of 100%.

[0052] (4) The green hydrogen supply rate curve and the hydrogen storage device hydrogen absorption rate curve are as follows Figure 6 During peak hours, there is an average rate redundancy of 0.726 kg / h per hour, and the device has greater flexibility potential. At the same time, the Pearson correlation coefficient between the hydrogen absorption curve and the hydrogen supply curve is 0.812. The hydrogen absorption rate and the hydrogen supply rate are strongly correlated, and the system operates in a more stable state.

[0053] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more. In the description of the present invention, a first feature "above" or "below" a second feature may include the first and second features being in direct contact, or the first and second features not being in direct contact but being in contact through another feature between them.

[0054] In the description of the present invention, “on”, “above” and “above” a first feature of a second feature include the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0055] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0056] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0057] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A hydrogen absorption method for a solid-state hydrogen storage device taking into account the fluctuation characteristics of green hydrogen production, characterized in that: The following steps are involved: S1, dividing the set time period into time intervals, and obtaining the variation pattern of renewable energy power generation within the set time period; S2: Construct the relationship between the average hydrogen absorption rate of a single hydrogen storage reactor and the hydrogen storage depth, and establish a hydrogen absorption rate model for a single hydrogen storage reactor; based on the variation pattern of renewable energy power generation, determine the number of hydrogen storage reactors that can meet the hydrogen storage demand within a set time period, and multiple hydrogen storage reactors form a hydrogen storage system; S3, allocating hydrogen flow to multiple hydrogen storage reactors under constraints in time intervals; giving priority to reactors with low hydrogen storage depths during peak periods, and giving priority to reactors with high hydrogen storage depths during off-peak periods; S4, determining whether the average hydrogen absorption rate of a single hydrogen storage reactor can meet the allocated hydrogen flow rate when executing the allocation method in S3 within the time interval, and if not, adjusting the allocated hydrogen flow rate of the hydrogen storage reactor; S5, repeat S3 and S4 until the average hydrogen absorption rate of each hydrogen storage reactor in each time interval can meet the corresponding hydrogen production, and the hydrogen absorption of the entire hydrogen storage system can meet all hydrogen production in the set time period. If satisfied, the allocation ends; if not satisfied, adjust the number of hydrogen storage reactors and repeat S2-S4.

2. A hydrogen absorption method for a solid-state hydrogen storage device taking into account the fluctuation characteristics of green hydrogen production according to claim 1, characterized in that: In S1, the time interval is obtained by dividing the set time period into equal intervals.

3. The hydrogen absorption method of a solid-state hydrogen storage device considering the fluctuation characteristics of green hydrogen production according to claim 1 is characterized in that: In S2, the relationship between the hydrogen absorption rate and the hydrogen storage depth is: （3） （4） Where, is the hydrogen storage depth; is the amount of hydrogen absorbed by the metal hydride, kg; is the total amount of hydrogen stored per hydrogen storage reactor, kg; It is the time change quantity, which has the same unit as the green hydrogen fluctuation and is based on hours; is the change in hydrogen storage capacity corresponding to time change, kg; is the hydrogen absorption rate, kg / h.

4. The hydrogen absorption method of a solid-state hydrogen storage device considering the fluctuation characteristics of green hydrogen production according to claim 1 is characterized in that: In S2, the formula for determining the number of hydrogen storage reactors that can meet the hydrogen storage demand within the set time period is: （10） Where, Number of solid-state hydrogen storage reactors, units; is the daily green hydrogen production of the electrolyzer, kg.

5. The hydrogen absorption method of a solid-state hydrogen storage device considering the fluctuation characteristics of green hydrogen production according to claim 1 is characterized in that: In S3, the constraints are: （11） （12） （13） Where, For the k The amount of hydrogen flow allocated in the green hydrogen production during the time period, kg / h; For the k -1 The hydrogen storage capacity of the reactor at the end of the time period, kg; For the k -1 The average hydrogen absorption rate of the reactor during the time period.

6. The hydrogen absorption method of a solid-state hydrogen storage device considering the fluctuation characteristics of green hydrogen production according to claim 1 is characterized in that: In S5, the process of S3 and S4 is repeated, and the average hydrogen absorption rate of the hydrogen storage reactor is updated for different time intervals: （17） Where, For this allocation i Average rate per reactor, kg / h, For the k At the end of the time period i The hydrogen storage depth of each reactor.

7. A hydrogen absorption method for a solid-state hydrogen storage device taking into account the fluctuation characteristics of green hydrogen production according to claim 6, characterized in that: The hydrogen storage depth is updated at different time intervals, and the update formula is: （14） （15） （16） Where, For the k At the end of the time period i Hydrogen storage capacity of each reactor, kg; For the k At the end of the time period i The hydrogen storage depth of each reactor.

8. The hydrogen absorption method of a solid-state hydrogen storage device considering the fluctuation characteristics of green hydrogen production according to claim 1 is characterized in that: In S5, the process of judging whether the average hydrogen absorption rate of the hydrogen storage reactor can meet the corresponding hydrogen production is as follows: judging whether the average hydrogen absorption rate of the hydrogen storage reactor is greater than the allocated hydrogen flow rate; if so, adjusting the allocated hydrogen flow rate.

9. The hydrogen absorption method of a solid-state hydrogen storage device considering the fluctuation characteristics of green hydrogen production according to claim 1 is characterized in that: The set time period is 24 hours, and the time interval is 1 hour.

10. A hydrogen absorption system for a solid-state hydrogen storage device taking into account the fluctuation characteristics of green hydrogen production, characterized in that: include: The time division module divides the set time period into time intervals, obtains the change pattern of renewable energy power generation within the set time period, and calculates the change pattern according to the change pattern; The model building module constructs the relationship between the average hydrogen absorption rate of a single hydrogen storage reactor and the hydrogen storage depth, and establishes a hydrogen absorption rate model for a single hydrogen storage reactor. Based on the variation pattern of renewable energy power generation, the number of hydrogen storage reactors that can meet the hydrogen storage demand within a set time period is determined, and multiple hydrogen storage reactors form a hydrogen storage system. The flow distribution module allocates hydrogen flow to multiple hydrogen storage reactors based on time intervals and constraints. During peak periods, reactors with low hydrogen storage depths are given priority, while during off-peak periods, reactors with high hydrogen storage depths are given priority. The flow rate judgment module judges whether the average hydrogen absorption rate of a single hydrogen storage reactor can meet the allocated hydrogen flow rate when executing the allocation method of the flow allocation module within the time interval. If not, adjust the allocated hydrogen flow rate of the hydrogen storage reactor; The flow adjustment module repeats the flow allocation module and the flow judgment module until the average hydrogen absorption rate of each hydrogen storage reactor in each time interval can meet the corresponding hydrogen production, and the hydrogen absorption of the entire hydrogen storage system can meet all hydrogen production in the set time period. If it is met, the allocation ends; if it is not met, the number of hydrogen storage reactors is adjusted, and the model construction module, flow allocation module and flow judgment module are repeated.

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