A power regulation method for a photovoltaic hydrogen storage system, a photovoltaic hydrogen storage system and a storage medium

Abstract

This invention relates to the field of photovoltaic hydrogen production technology, and more particularly to a power regulation method for a photovoltaic hydrogen storage system, a photovoltaic hydrogen storage system, and a storage medium. This invention obtains the photovoltaic power generation by smoothing and filtering the output power of the photovoltaic module. Based on the state of charge (SOC) value of the energy storage battery and the desired SOC operating range, a target SOC value for PI control of the energy storage battery is determined. A charge difference is determined based on the target SOC value and the SOC value, and PI control is performed based on this charge difference to determine the operating power adjustment value of the electrolyzer. Finally, a smooth and stable target operating power value for the electrolyzer is determined based on the photovoltaic power generation and the operating power adjustment value. This allows for smooth and stable adjustment of the electrolyzer's operating power according to the target operating power value, reducing or avoiding large power fluctuations during power control and extending the electrolyzer's service life.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic hydrogen production technology, and in particular to a power regulation method for a photovoltaic hydrogen storage system, a photovoltaic hydrogen storage system and a storage medium. Background Technology

[0002] With the transformation of the global energy structure and the severe challenges of climate change, the development and utilization of renewable energy has become a focus of international attention. Solar energy, as one of the richest and cleanest renewable energy sources, has seen significant progress in photovoltaic power generation technology in recent years and has been widely applied globally. As the cost of photovoltaic power generation decreases, photovoltaic hydrogen production / storage is considered an important path to achieving "green hydrogen" production. Hydrogen production equipment or devices (such as electrolyzers) are expected to operate at stable power levels to extend their lifespan and improve efficiency. However, the intermittent and fluctuating power of photovoltaic power generation poses a severe challenge to the stable operation of hydrogen production equipment. Related technologies introduce batteries as energy storage systems, forming a photovoltaic-hydrogen storage system together with the photovoltaic power generation system and hydrogen production equipment. Among these technologies, the power control of hydrogen production equipment mainly suffers from the following two methods and their inherent defects:

[0003] 1) Photovoltaic power tracking method: This method allows the power of the hydrogen production equipment to follow the changes in photovoltaic power as closely as possible in real time. The drawback of this method is that the hydrogen production equipment is sensitive to power fluctuations. Frequent and drastic power changes will accelerate the aging of the hydrogen production equipment, affecting its service life and hydrogen production efficiency. To alleviate this problem, it is necessary to configure supercapacitors with extremely fast response speeds, which increases the complexity and cost of the photovoltaic hydrogen storage system.

[0004] 2) Power Supply After Full Smoothing Through Energy Storage System: This method involves configuring large-capacity batteries to fully smooth the photovoltaic power generation before supplying highly stable power to the hydrogen production equipment. The drawbacks of this method are: extremely high battery capacity requirements, leading to a significant increase in system costs; and the batteries need to absorb or release all the fluctuating energy from the photovoltaic power generation, acting as the primary energy buffer rather than a power regulator. Furthermore, the batteries are prone to extreme states of being fully charged or discharged, at which point the system must limit photovoltaic power generation or shut down the hydrogen production equipment, reducing the overall system operating efficiency and energy utilization rate. Summary of the Invention

[0005] In view of this, one objective of the embodiments of the present invention is to provide a power regulation method for a photohydrogen storage system, a photohydrogen storage system and a storage medium, aiming to solve the technical problem of large power fluctuations during the power regulation process of the electrolyzer in the photohydrogen storage system.

[0006] To address the aforementioned technical problems, the embodiments of the present invention provide the following technical solutions:

[0007] In a first aspect, embodiments of the present invention provide a power regulation method for a photovoltaic hydrogen storage system, comprising:

[0008] The output power of the photovoltaic module at the current moment is filtered to obtain the photovoltaic power generation power of the photovoltaic module at the current moment;

[0009] Based on the relationship between the current state of charge (SOC) value of the energy storage battery and the expected SOC operating range, the target SOC value of the PI-controlled energy storage battery at the current moment is determined.

[0010] The charge difference of the energy storage battery at the current moment is determined based on the difference between the current state of charge value of the energy storage battery and the current target charge value.

[0011] Based on the charge difference at the current moment, PI control is used to determine the current working power adjustment value of the electrolytic cell.

[0012] The target operating power value of the electrolytic cell is determined based on the current photovoltaic power generation and the current operating power adjustment value.

[0013] In some embodiments, the target charge value of the PI-controlled energy storage battery at the current moment is determined based on the relationship between the current state of charge (SOC) value of the energy storage battery and the desired charge operating range of the energy storage battery, including:

[0014] In response to the fact that the current state of charge value is greater than the maximum value of the expected charge working range, the difference between the current state of charge value and the first preset charge value is calculated to obtain the target charge value at the current time.

[0015] In response to the current state of charge value being greater than the mean of the charge interval and less than or equal to the maximum value, the difference between the current state of charge value and the second preset charge value is calculated to obtain the target charge value at the current time. The mean of the charge interval is the average of the maximum and minimum values ​​of the desired charge working interval.

[0016] In response to the fact that the current state of charge value is equal to the mean of the charge interval, the current state of charge value is determined to be the target charge value for the current time.

[0017] In response to the current state of charge value being greater than or equal to the minimum value of the desired charge working range and less than the average value of the charge range, the current state of charge value is summed with the second preset charge value to obtain the target charge value at the current time.

[0018] In response to the fact that the current state of charge value is less than the minimum value, the current state of charge value is summed with the first preset charge value to obtain the target charge value at the current time.

[0019] Wherein, both the first preset charge value and the second preset charge value are greater than 0, and the first preset charge value is greater than the second preset charge value.

[0020] In some embodiments, PI control is performed based on the charge difference at the current moment to determine the operating power adjustment value of the electrolyzer at the current moment, including:

[0021] Based on the integral term in the PI control process at the previous moment and the charge difference at the current moment, determine the integral term in the PI control process at the current moment.

[0022] Based on the integral term from the previous moment and the charge difference at the current moment, determine the operating power adjustment value of the electrolytic cell at the current moment;

[0023] In the PI control process, the initial value of the integral term is zero.

[0024] In some embodiments, determining the integral term in the PI control process at the current moment based on the integral term in the PI control process at the previous moment and the charge difference at the current moment includes:

[0025] Obtain the product of the current charge difference and the integral coefficient;

[0026] Summing the product and the integral term from the previous time step, we determine the integral term at the current time step.

[0027] In some embodiments, determining the current electrolytic cell operating power adjustment value based on the integral term from the previous time step and the charge difference from the current time step includes:

[0028] Obtain the product of the current charge difference and the scaling factor;

[0029] Summing the product and the integral term from the previous time step, we determine the operating power adjustment value for the current time step.

[0030] In some embodiments, determining the target operating power value of the electrolyzer based on the current photovoltaic power generation and the current operating power adjustment value includes:

[0031] The target operating power value is obtained by adding the current photovoltaic power generation power to the current operating power adjustment value.

[0032] In some embodiments, after determining the target operating power value of the electrolytic cell, the method further includes: gradually adjusting the operating power of the electrolytic cell to the target operating power value during at least one adjustment cycle, including:

[0033] Obtain the absolute power difference between the actual operating power of the electrolytic cell at the current moment and the target operating power value at the current moment;

[0034] When the absolute power difference at the current moment is greater than the power change threshold, the sum of the power change threshold and the actual working power at the current moment shall be used as the adjusted working power of the electrolytic cell for the current adjustment cycle.

[0035] When the absolute power difference at the current moment is less than or equal to the power change threshold, the working power of the electrolytic cell is adjusted to the target working power value.

[0036] In some embodiments, filtering the output power of the photovoltaic module at the current moment to obtain the photovoltaic power generation of the photovoltaic module at the current moment includes:

[0037] Obtain the N photovoltaic power generation values ​​of the photovoltaic module N times ago;

[0038] Calculate the average of the output power of N photovoltaic power units and the output power of the photovoltaic module at the current moment to obtain the photovoltaic power generation at the current moment.

[0039] In a second aspect, embodiments of the present invention provide a photoelectric hydrogen storage system, comprising:

[0040] A DC-DC converter and a photovoltaic module, energy storage battery and electrolytic cell connected to the DC-DC converter;

[0041] The processor, connected to the energy storage battery, the photovoltaic module, and the electrolyzer, is used to acquire the output power of the photovoltaic module, the state of charge value of the energy storage battery, and the operating power of the electrolyzer, and to execute any of the power regulation methods for the photovoltaic hydrogen storage system proposed in the first aspect.

[0042] Thirdly, embodiments of the present invention provide a computer-readable storage medium storing processor-executable computer program instructions, which, when executed by a processor, cause the computer to perform any of the power regulation methods for a photovoltaic hydrogen storage system proposed in the first aspect.

[0043] The embodiments of the present invention have the following beneficial effects: Unlike related technologies, the power regulation method for a photovoltaic hydrogen storage system provided in the embodiments of the present invention includes: filtering the output power of the photovoltaic module at the current moment to obtain the photovoltaic power generation of the photovoltaic module at the current moment; determining the target charge value of the energy storage battery under PI control at the current moment based on the relationship between the state of charge value of the energy storage battery at the current moment and the desired charge operating range of the energy storage battery; determining the charge difference value of the energy storage battery at the current moment based on the difference between the state of charge value of the energy storage battery at the current moment and the target charge value at the current moment; performing PI control based on the charge difference value at the current moment to determine the operating power adjustment value of the electrolyzer at the current moment; and determining the target operating power value of the electrolyzer based on the photovoltaic power generation and the operating power adjustment value at the current moment.

[0044] This invention provides a method for smoothing and filtering the output power of photovoltaic modules to obtain photovoltaic power generation. Based on the state of charge (SOC) value and desired SOC operating range of the energy storage battery, a target SOC value for PI control of the energy storage battery is determined. A charge difference is then determined based on the target SOC value and the SOC value, and PI control is applied based on this charge difference to determine the operating power adjustment value of the electrolyzer. Finally, a smooth and stable target operating power value for the electrolyzer is determined based on the photovoltaic power generation and the operating power adjustment value. This allows for smooth and stable adjustment of the electrolyzer's operating power, reducing or avoiding large power fluctuations during power control, extending the electrolyzer's lifespan, eliminating the need for high-performance supercapacitors and energy storage batteries, reducing system cost and complexity, and improving system operating efficiency. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the prior art or embodiments will be briefly introduced below. Obviously, the drawings described below only show some embodiments of the present invention and should not be considered as limiting the scope of protection. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram illustrating the application scenario of the power regulation method for the photovoltaic hydrogen storage system in some embodiments of the present invention;

[0047] Figure 2 These are schematic diagrams of the structure of a photoelectric hydrogen storage system provided in some embodiments of the present invention;

[0048] Figure 3 This is a schematic flowchart of a power regulation method for a photovoltaic hydrogen storage system provided in some embodiments of the present invention;

[0049] Figure 4 yes Figure 3 A schematic diagram of a sub-process of step S41 in the power regulation method of the photovoltaic hydrogen storage system shown in the embodiment;

[0050] Figure 5 yes Figure 3 A schematic diagram of a sub-process of step S42 in the power regulation method of the photovoltaic hydrogen storage system shown in the embodiment;

[0051] Figure 6 yes Figure 3 A schematic diagram of a sub-process of step S44 in the power regulation method of the photovoltaic hydrogen storage system shown in the embodiment;

[0052] Figure 7 yes Figure 3A schematic diagram of a sub-process of step S45 in the power regulation method of the photovoltaic hydrogen storage system shown in the embodiment;

[0053] Figure 8 This is a schematic diagram illustrating the calculation of the working power adjustment value by the PI control process in some embodiments of the present invention;

[0054] Figure 9a This is a schematic diagram illustrating the operation of photovoltaic modules, electrolytic cells, and energy storage batteries in some embodiments of the present invention, wherein the capacity of the energy storage battery is 10kWh;

[0055] Figure 9b This is a schematic diagram illustrating the operation of the photovoltaic module, electrolytic cell, and energy storage battery in some embodiments of the present invention, wherein the capacity of the energy storage battery is 5kWh;

[0056] Figure 10a This is a schematic diagram of the operation of the photovoltaic module, electrolytic cell and energy storage battery in other embodiments of the present invention, wherein the capacity of the energy storage battery is 10kWh;

[0057] Figure 10b This is a schematic diagram of the operation of the photovoltaic module, electrolytic cell and energy storage battery in other embodiments of the present invention, wherein the capacity of the energy storage battery is 10kWh;

[0058] Figure 10c This is a schematic diagram illustrating the operation of the photovoltaic module, electrolytic cell, and energy storage battery in other embodiments of the present invention, wherein the capacity of the energy storage battery is 10kWh. Detailed Implementation

[0059] To make the objectives and advantages of the embodiments of the present invention more readily understood, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The detailed description of the embodiments of the present invention in the accompanying drawings is not intended to limit the scope of protection claimed by the present invention, but only to illustrate selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] It should be noted that, unless there is a conflict, the various technical features involved in the embodiments of the present invention described below can be combined with each other, and all are within the protection scope of the present invention. Furthermore, although functional modules are divided in the device or structural schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. In addition, the terms "first," "second," "third," and other similar expressions used herein do not limit the data or execution order, but are only for illustrative purposes and to distinguish identical or similar items with substantially the same function and effect, and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features.

[0061] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. It should be understood that the term "and / or" as used herein includes any and all combinations of one or more of the listed items.

[0062] In related technologies, the power control strategies for electrolyzers in photovoltaic hydrogen storage systems mainly fall into two categories and their inherent drawbacks:

[0063] 1) Direct Photovoltaic Power Tracking Strategy: This strategy aims to make the electrolyzer power follow changes in photovoltaic power as closely as possible in real time. However, this strategy has a drawback: the electrolyzer is highly sensitive to power fluctuations. Frequent and drastic power changes accelerate the aging of the electrolyzer, affecting its lifespan and hydrogen production efficiency. To mitigate this problem, high-performance supercapacitors with extremely fast response times are required, increasing system complexity and cost.

[0064] 2) Power Supply Strategy Through Complete Energy Storage Smoothing: This strategy involves configuring large-capacity, high-performance batteries to completely smooth the photovoltaic power before supplying highly stable power to the electrolyzer. The drawback of this strategy is that it places extremely high demands on the capacity and performance of the batteries, leading to a significant increase in cost. The batteries need to absorb or release all the fluctuating energy from the photovoltaic power generation, acting as the primary energy buffer rather than a power regulator. Furthermore, the batteries are prone to extreme states of being fully charged or discharged, at which point the system must limit photovoltaic power or shut down the electrolyzer, reducing overall operating efficiency and energy utilization.

[0065] In summary, the core problem with the relevant technologies lies in the failure to effectively coordinate and decouple the short-term power fluctuation management of photovoltaics from the long-term energy balance management of the system, and the inability to achieve a good balance among the three objectives of "reducing the cost of energy storage configuration", "smoothing the power of electrolyzers" and "maximizing the utilization of photovoltaic energy".

[0066] In view of this, embodiments of the present invention provide a power regulation method for a photovoltaic hydrogen storage system. The method involves smoothing and filtering the output power of the photovoltaic module to obtain the photovoltaic power generation. Based on the state of charge (SOC) value and desired SOC operating range of the energy storage battery, a target SOC value for PI control of the energy storage battery is determined. A charge difference is determined based on the target SOC value and the SOC value. PI control is then performed based on this charge difference to determine the operating power adjustment value of the electrolyzer. Finally, a smooth and stable target operating power value for the electrolyzer is determined based on the photovoltaic power generation and the operating power adjustment value. This allows for smooth and stable adjustment of the electrolyzer's operating power, reducing or avoiding large power fluctuations during power control, extending the electrolyzer's lifespan, eliminating the need for high-performance supercapacitors and energy storage batteries, reducing system cost and complexity, and improving system operating efficiency.

[0067] Please refer to the following: Figure 1 and Figure 2 , Figure 1 The schematic diagram illustrates an application scenario of the power control method for a photovoltaic hydrogen storage system provided in some embodiments of the present invention. Figure 2 The schematic diagram illustrates the structure of a photohydrogen storage system provided in some embodiments of the present invention.

[0068] See Figure 1 or Figure 2 As shown, the photovoltaic hydrogen storage system 100 includes an energy storage battery 110, a photovoltaic module 120, a DC-DC converter 130, an electrolyzer 140, and a processor 150. The energy storage battery 110, photovoltaic module 120, and electrolyzer 140 are all electrically connected to the DC-DC converter 130, and the processor 150 is communicatively connected to the energy storage battery 110, photovoltaic module 120, and electrolyzer 140.

[0069] For example, the photovoltaic module 120 serves as the energy source for the photovoltaic hydrogen storage system 100, converting solar energy into electrical energy and outputting the electrical energy to the DC-DC converter 130. The output power of the photovoltaic module 120 dynamically changes with the light intensity. The electrical energy is output from the DC-DC converter 130 to the electrolyzer 140 for use or to the energy storage battery 110 for storage.

[0070] In some embodiments of the present invention, the DC-DC converter 130 serves as an energy dispatching device. It dynamically adjusts impedance matching using the MPPT (Maximum Power Point Tracking) algorithm to maximize photovoltaic power generation efficiency and converts photovoltaic output power into stable DC power required by the electrolyzer 140 and the energy storage battery 110, and outputs the converted DC power to the electrolyzer 140 or the energy storage battery 110.

[0071] As an energy buffer device, the energy storage battery 110 can be a standard-performance battery, without the need for high-capacity or high-performance configurations. The energy storage battery 110 compensates for the fluctuations in photovoltaic power generation and the response delay of the photovoltaic-hydrogen storage system 100 through its rapid charge-discharge characteristics, ensuring the stable operation and efficient energy utilization of the photovoltaic-hydrogen storage system 100. When the output power of the photovoltaic module 120 is insufficient, the energy storage battery 110 discharges instantaneously to compensate for the power shortfall, maintaining the continuous operation of the electrolyzer 140. When the output power of the photovoltaic module 120 is excessive, the energy storage battery 110 stores surplus energy to prevent wasted solar power. In this way, large power fluctuations in the electrolyzer 140 are reduced or avoided, ensuring a continuous and stable power supply to the electrolyzer 140.

[0072] In this embodiment, the electrolyzer 140 serves as a hydrogen production terminal, receiving stable electrical energy from the DC converter 130 to drive the water electrolysis reaction to produce hydrogen. The produced hydrogen can be supplied to other industries.

[0073] For example, the processor 150 is configured to acquire the output power of the photovoltaic module 120, the state of charge (SOC) value of the energy storage battery 110, and the operating power of the electrolyzer 140, and coordinate the various components in the photovoltaic hydrogen storage system 100 to work together to complete the adjustment and control of the operating power of the electrolyzer 140.

[0074] For example, in this embodiment of the invention, after obtaining the output power of the photovoltaic module 120, the output power of the photovoltaic module 120 at the current moment is filtered to obtain the photovoltaic power generation power of the photovoltaic module 120 at the current moment. After obtaining the state of charge (SOC) value of the energy storage battery 110 at the current moment, this embodiment of the invention determines the target SOC value of the PI-controlled energy storage battery 110 at the current moment based on the SOC value of the energy storage battery 110 at the current moment and the preset expected SOC operating range of the energy storage battery 110. It should be understood that engineers can customize and set the expected SOC operating range based on engineering experience and battery characteristics.

[0075] In this embodiment of the invention, the difference between the current state of charge (SOC) value of the energy storage battery 110 and the current target SOC value is calculated to obtain the current SOC difference value of the energy storage battery 110. Based on this current SOC difference value, PI control is performed to determine the current operating power adjustment value of the electrolytic cell 140.

[0076] After obtaining the photovoltaic power generation of the photovoltaic module 120 and the operating power adjustment value of the electrolytic cell 140 at the current moment, this embodiment of the invention determines the target operating power value of the electrolytic cell 140 at the current moment based on the photovoltaic power generation of the photovoltaic module 120 and the operating power adjustment value of the electrolytic cell 140 at the current moment. Thus, this embodiment of the invention can smoothly and stably adjust the operating power of the electrolytic cell 140 according to the target operating power value of the electrolytic cell 140 at the current moment.

[0077] It should be understood that Figure 1 and Figure 2 This illustration merely depicts one scenario of power regulation in the photovoltaic hydrogen storage system 100 according to some embodiments of the present invention. It does not limit the structure, type, or quantity of the photovoltaic hydrogen storage system 100 in other application scenarios. Other embodiments of the photovoltaic hydrogen storage system may also include... Figure 1 and Figure 2 The structure shown has more or fewer components, or has the same as Figure 1 and Figure 2 The diagram shows different configurations of the structure.

[0078] As can be understood from the above, the implementing entity of the power regulation method for the photovoltaic hydrogen storage system provided in this embodiment of the invention can be any suitable type of processor with certain computing and control capabilities, such as the processor 150 mentioned above.

[0079] The power regulation method for a photohydrogen storage system provided in this invention will be described in detail below, taking into account exemplary applications and implementations of the processor provided in the embodiments of this invention.

[0080] Please see Figure 3 , Figure 3 The schematic diagram illustrates a flow chart of a power regulation method for a photoelectric hydrogen storage system provided in some embodiments of the present invention.

[0081] like Figure 3 As shown, the power regulation method for the photovoltaic hydrogen storage system includes, but is not limited to, the following steps S41-S45.

[0082] S41: Filter the output power of the photovoltaic module at the current moment to obtain the photovoltaic power generation of the photovoltaic module at the current moment.

[0083] In some embodiments of the present invention, the output power of the photovoltaic module at the current moment is obtained, and the output power at the current moment is filtered using a first-order low-pass filter. That is, based on the output power of the photovoltaic module at the current moment and the power filtering result at the previous moment, the output power at the current moment is updated according to a preset filtering coefficient to obtain the filtered output result at the current moment. The filtered output result at the current moment is the photovoltaic power generation power of the photovoltaic module at the current moment.

[0084] In some embodiments, the output power at the current moment is filtered using a median filtering method. That is, the median of the output power of the photovoltaic module is taken within a fixed time window, the output power of the photovoltaic module at the current moment and the nearby moments are sorted, and the median value of the sorted output power is taken as the photovoltaic power generation of the photovoltaic module at the current moment.

[0085] Please see Figure 4 , Figure 4 The illustration shows a sub-process diagram of step S41 in the power control method of the photovoltaic hydrogen storage system provided in some embodiments of the present invention.

[0086] like Figure 4 As shown, the output power of the photovoltaic module at the current moment is filtered to obtain the photovoltaic power generation of the photovoltaic module at the current moment, specifically including but not limited to the following steps S411-S412:

[0087] S411: Obtain the N photovoltaic power generation of the photovoltaic module N times ago.

[0088] S412: Calculate the average of the output power of N photovoltaic power units and the output power of the photovoltaic module at the current moment to obtain the photovoltaic power generation at the current moment.

[0089] In step S411, based on the timestamp of the current time, determine the N timestamps that are before the current timestamp, and obtain the photovoltaic power generation of the photovoltaic module at each of the N timestamps (i.e., the power obtained after smoothing and filtering the output power at each time), thus obtaining the N photovoltaic power generation of the photovoltaic module at the first N timestamps.

[0090] In step S412, the average of the N photovoltaic power generation values ​​and the current output power of the photovoltaic module is calculated, and this average value is used as the photovoltaic power generation value of the photovoltaic module at the current moment. For example, the N photovoltaic power generation values ​​and the current output power of the photovoltaic module are substituted into the formula: Calculate the photovoltaic power generation of the photovoltaic module at the current time t. Wherein, This represents the photovoltaic power generation capacity of the photovoltaic module at the current moment. It is the sum of the power generated by N photovoltaic cells. The output power of the photovoltaic module at the current moment. This represents the number of moments preceding the current moment.

[0091] In this embodiment, the purpose of filtering the output power of the photovoltaic module at the current moment is to remove high-frequency noise from the output power, extract its changing trend, and use it as a reference for subsequent calculation of the target working power value of the electrolytic cell, thereby improving the accuracy of the calculation.

[0092] S42: Based on the relationship between the current state of charge (SOC) value of the energy storage battery and the desired SOC operating range, determine the target SOC value of the PI-controlled energy storage battery at the current moment.

[0093] Specifically, the current state of charge (SOC) value of the energy storage battery is compared with the expected SOC operating range of the energy storage battery. Based on the relationship between the current SOC value and the expected SOC operating range of the energy storage battery, different calculation methods are used to calculate and determine the target SOC value of the PI-controlled energy storage battery at the current moment.

[0094] Understandably, engineers can customize the desired charge operating range of the energy storage battery based on engineering experience and experimental data, such as the desired charge operating range being [40%, 60%]. This embodiment of the invention does not impose any limitations on this.

[0095] Please see Figure 5 , Figure 5 The illustration shows a sub-process diagram of step S42 in the power regulation method of the photovoltaic hydrogen storage system provided in some embodiments of the present invention.

[0096] See Figure 5 As shown, based on the relationship between the current state of charge (SBC) value of the energy storage battery and its desired operating range, the target SBC value for the PI-controlled energy storage battery at the current moment is determined, specifically including but not limited to the following steps S421-S425:

[0097] S421: In response to the current state of charge value being greater than the maximum value of the desired charge working range, calculate the difference between the current state of charge value and the first preset charge value to obtain the target charge value at the current time.

[0098] Where t represents the current time. In this embodiment, the desired charging operating range is... , This is the minimum value of the desired charged operating range. This represents the maximum value of the desired charged operating range.

[0099] If the current state of charge value Greater than the maximum value of the desired charge operating range That is, if Based on the current state of charge value and the first preset charge value The difference is used to obtain the target charge value at the current moment. ;

[0100] Right now: .

[0101] Understandably, engineers can customize and set the first preset charge value based on their engineering experience and experimental data. For example, the first preset charge value It can be 1%, 2%, or any other suitable value.

[0102] S422: In response to the current state of charge value being greater than the average value of the charge interval and less than or equal to the maximum value, calculate the difference between the current state of charge value and the second preset charge value to obtain the target charge value at the current time.

[0103] Among them, the mean of the charge interval The maximum value of the desired charged operating range and minimum value The mean, that is: .

[0104] If the current state of charge value Greater than the average value of the charging interval And less than or equal to the maximum value of the desired charge operating range. That is, if Based on the current state of charge value With the second preset charge value The difference is used to obtain the target charge value at the current moment. ;

[0105] Right now: .

[0106] Understandably, engineers can customize and set a second preset charge value based on their engineering experience and experimental data. For example, the second preset charge value The value is 0.1%, 0.2%, or any other suitable value. In this embodiment of the invention, the first preset charge value... Second preset charge value All are greater than 0, and the first preset charge value Greater than the second preset charge value .

[0107] S423: In response to the fact that the current state of charge value is equal to the mean of the charge interval, determine the current state of charge value as the target charge value for the current time.

[0108] For example, if the current state of charge value Equal to the mean of the charge interval That is, if Determine the current state of charge value. The target charge value at the current moment ,Right now: .

[0109] S424: In response to the current state of charge value being greater than or equal to the minimum value of the desired charge working range and less than the average value of the charge range, sum the current state of charge value with the second preset charge value to obtain the target charge value at the current time.

[0110] If the current state of charge value Greater than or equal to the minimum value of the desired charged operating range And less than the average value of the charging interval. That is, if Based on the current state of charge value With the second preset charge value The sum of these values ​​yields the target charge value at the current moment. ;

[0111] Right now: .

[0112] S425: In response to the current state of charge value being less than the minimum value, sum the current state of charge value with the first preset charge value to obtain the target charge value at the current time.

[0113] If the current state of charge value Less than the minimum value of the desired charged operating range That is, if Based on the current state of charge value Compared with the first preset charge value The sum of these values ​​yields the target charge value at the current moment. ;

[0114] Right now: .

[0115] In this embodiment, instead of directly fixing the target charge value of the energy storage battery to a certain charge value within the desired charge operating range, a method of dynamically adjusting the target charge value of the energy storage battery is used to slowly adjust the SOC of the energy storage battery to the desired charge operating range. This avoids the situation where the initial charge value of the energy storage battery easily enters integral saturation, leading to overshoot of the state of charge (SOC), when the initial SOC differs significantly from the target SOC. When the SOC is outside the desired operating range, the target SOC is adjusted in larger increments (e.g., 1%-5%) to quickly bring the SOC closer to the desired operating range. When the SOC is within the desired operating range, the target SOC is adjusted in smaller increments (e.g., 0.1%-0.5%) to slowly bring the SOC towards the midpoint of the desired operating range (i.e., the target SOC is within the desired operating range). )near.

[0116] S43: Determine the charge difference of the energy storage battery at the current moment based on the difference between the current state of charge value of the energy storage battery and the current target charge value.

[0117] For example, the current state of charge value Subtract the target charge value at the current moment This gives the current charge difference of the energy storage battery. ;

[0118] Right now: .

[0119] S44: Based on the charge difference at the current moment, perform PI control to determine the current operating power adjustment value of the electrolytic cell.

[0120] See Figure 8 As shown above, the charge difference of the energy storage battery at the current moment... The current charge difference of the energy storage battery The input is sent to the PI controller, which uses the charge difference of the energy storage battery at the current moment. Calculations are performed to obtain the current operating power adjustment value of the electrolyzer. .

[0121] Please see Figure 6 , Figure 6 The illustration shows a sub-process diagram of step S44 in the power regulation method of the photohydrogen storage system provided in some embodiments of the present invention.

[0122] See Figure 6 As shown, PI control is performed based on the charge difference at the current moment to determine the operating power adjustment value of the electrolytic cell at the current moment, specifically including but not limited to the following steps S441-S442.

[0123] S441: Determine the integral term in the PI control process at the current moment based on the integral term in the PI control process at the previous moment and the charge difference at the current moment;

[0124] Among them, the integral term in the PI control process The initial value is zero, that is , where t=0 represents the start time of the PI control process.

[0125] Specifically, obtain the integral term of the PI control process at the previous moment. Based on the integral term in the PI control process of the previous moment With the first integral coefficient The product is obtained by the first integral product. ,Right now: Based on the current charge difference of the energy storage battery. The first PI coefficient in the PI control process The product of these two products yields the first PI product. ,Right now: Based on the first PI product Product with the first integral The sum of these values ​​yields the integral term in the PI control process at the current moment. ,Right now: In this embodiment, the previous moment is the moment that is before the current moment and adjacent to the current moment.

[0126] In one embodiment, based on the integral term in the PI control process at the previous moment... The difference in charge with the current moment Determine the integral term in the PI control process at the current moment. The specific process is as follows:

[0127] Get the charge difference at the current moment. and integral coefficient product ;

[0128] Right now: .

[0129] For product The integral term from the previous moment Summation to determine the integral term at the current time step. ;

[0130] Right now: .

[0131] S442: Based on the integral term of the previous moment and the charge difference of the current moment, determine the working power adjustment value of the electrolytic cell at the current moment;

[0132] Specifically, obtain the integral term of the PI control process at the previous moment. Based on the integral term in the PI control process of the previous moment With the second integral coefficient The product is obtained by the second integral product. ,Right now: Based on the current charge difference of the energy storage battery. The second PI coefficient in the PI control process The product of and is used to obtain the second PI product. ,Right now: Based on the second PI product Product with the second integral The sum of these values ​​yields the current operating power adjustment value of the electrolytic cell. ,Right now: .

[0133] In one embodiment, based on the integral term from the previous time step The difference in charge with the current moment Determine the current operating power adjustment value of the electrolyzer. The specific process is as follows:

[0134] Get the charge difference at the current moment. and proportionality coefficient product ;

[0135] Right now: .

[0136] For product The integral term from the previous moment Sum the values ​​to determine the current operating power adjustment value. ;

[0137] Right now: .

[0138] S45: Determine the target operating power value of the electrolytic cell based on the current photovoltaic power generation and the current operating power adjustment value.

[0139] It is understandable that the target operating power value of the electrolytic cell is... It needs to be limited to the operating power range of the electrolyzer, that is, the target operating power value of the electrolyzer. Greater than or equal to the lower limit of the working power of the electrolytic cell And less than or equal to the upper limit of the working power of the electrolytic cell. .

[0140] Please see Figure 7 , Figure 7 The illustration shows a sub-process diagram of step S45 in the power regulation method of the photovoltaic hydrogen storage system provided in some embodiments of the present invention.

[0141] See Figure 7 As shown, in some embodiments, the target operating power value of the electrolyzer is determined based on the current photovoltaic power generation and the current operating power adjustment value, specifically including but not limited to the following step S451:

[0142] S451: Add the current photovoltaic power generation to the current operating power adjustment value to obtain the target operating power value;

[0143] That is, the target operating power value is equal to the sum of the photovoltaic power generation at the current moment and the operating power adjustment value at the current moment. .

[0144] In some embodiments, after determining the target operating power value of the electrolyzer, the power regulation method for the photovoltaic hydrogen storage system further includes, but is not limited to, the following step S46:

[0145] S46: Gradually adjust the operating power of the electrolytic cell to the target operating power value during at least one adjustment cycle. .

[0146] Among them, the target operating power value of the electrolytic cell is obtained. Subsequently, to avoid the impact of sudden power changes on the electrolytic cell, the target operating power value of the electrolytic cell was set. A gradual change process is implemented. Specifically, a power change threshold is set. (For example, not exceeding 5% of the electrolyzer's rated power per second), calculate the current actual power of the electrolyzer during each power adjustment cycle. With the target operating power value The difference If the difference Exceeding the power change threshold Allowable range (i.e., difference) Greater than the power change threshold ), then according to the power change threshold Gradually adjust the operating power of the electrolytic cell so that it gradually approaches the target operating power value. If the difference At the power change threshold Within the allowable range (i.e., the difference) Less than or equal to the power change threshold If so, the operating power of the electrolytic cell will be directly adjusted to the target operating power value. .

[0147] The aforementioned power variation control ensures a smooth change in the electrolytic cell's operating power, protecting it from damage caused by sudden power fluctuations and improving system stability and reliability. It should be understood that the power variation threshold... Related to the performance parameters of the electrolytic cell itself, the change in the operating power of the electrolytic cell per second is not allowed to exceed the power threshold (i.e., the power change threshold). In some embodiments, the power change threshold Set as the rated power of the electrolytic cell The preset multiple value, such as 1.2%, is used to set the power change threshold. 1.2% × rated power of the electrolytic cell .

[0148] In one embodiment, the operating power of the electrolyzer is gradually adjusted to the target operating power value during at least one adjustment cycle. The specific process is as follows:

[0149] Obtain the actual operating power of the electrolyzer at the current moment. and the target operating power value at the current moment absolute power difference ;

[0150] Right now: .

[0151] When the absolute power difference at the current moment Greater than the power change threshold At that time, that is At that time, based on the power change threshold and the actual operating power at the current moment The sum of these values ​​represents the adjusted operating power of the electrolyzer during the current adjustment cycle. ,Right now: .

[0152] When the absolute power difference at the current moment Less than or equal to the power change threshold At that time, that is At that time, adjust the working power of the electrolytic cell to the target working power value. .

[0153] In general, the embodiments of the present invention have at least the following significant beneficial effects:

[0154] 1. Significantly Reduced Battery Capacity and Cost of Photovoltaic-Hydrogen Storage Systems: Because the control strategy automatically maintains the battery's State of Charge (SOC) at the midpoint of the desired operating range, the battery only needs to handle short-term power fluctuations, rather than storing hours' worth of electricity generated by the photovoltaic modules. This significantly reduces the required battery capacity, substantially lowering the cost of the most expensive component in photovoltaic-hydrogen storage systems. (See also...) Figure 9a and Figure 9b As shown, the operating conditions are basically the same when the energy storage battery capacity is 10kWh and 5kWh. Figure 9a and Figure 9b In this context, the upper limit of electrolytic cell power refers to the upper limit of the electrolytic cell's operating power. The lower limit of electrolytic cell power refers to the lower limit of the operating power of the electrolytic cell. The SOC upper limit refers to the maximum value of the expected charged operating range of an energy storage battery. The State of Charge (SOC) lower limit refers to the minimum value of the expected charged operating range of an energy storage battery. .

[0155] 2. Optimize system operation and extend equipment life:

[0156] For energy storage batteries: Active control prevents the battery from entering extreme operating conditions such as "no-charge" (i.e., overcharging, full charging) or "no-discharge" (i.e., over-discharging, emptying), reducing deep charge-discharge cycles and effectively extending the battery's lifespan. See also... Figure 10a and Figure 10b As shown, when the SOC of the energy storage battery deviates from the desired charging operating range (i.e., the middle charging range) When the power is adjusted, the SOC of the energy storage battery is brought back to the desired operating range. Figure 10a and Figure 10b In this context, the upper limit of electrolytic cell power refers to the upper limit of the electrolytic cell's operating power. The lower limit of electrolytic cell power refers to the lower limit of the operating power of the electrolytic cell. The SOC upper limit refers to the maximum value of the expected charged operating range of an energy storage battery. The State of Charge (SOC) lower limit refers to the minimum value of the expected charged operating range of an energy storage battery. .

[0157] For electrolyzers: Compared to direct photovoltaic (PV) power tracking, power command fluctuations after smoothing filtering are smoother, reducing power stress on the electrolyzer. If PV power is not smoothed, the PV power curve will exhibit spikes and glitches. Since the electrolyzer's operating power follows the PV power, this would result in the electrolyzer's operating power being identical to the PV power, lacking smoothness. After smoothing filtering, the PV power curve becomes smoother, allowing the electrolyzer's operating power to change smoothly, thus reducing power stress. This approach, while maintaining a relatively smooth power supply (meaning the electrolyzer's operating power remains at a fixed value), also preserves necessary power variation flexibility, improving adaptability and the direct PV absorption rate. (See also...) Figure 10c As shown, the short-term photovoltaic power generation fluctuates significantly, while the operating power of the electrolytic cell remains stable. Figure 10c In this context, the SOC upper limit refers to the maximum value of the expected charged operating range of an energy storage battery. The State of Charge (SOC) lower limit refers to the minimum value of the expected charged operating range of an energy storage battery. .

[0158] 3. Improve the direct utilization rate of photovoltaic power generation and the operating efficiency of photovoltaic hydrogen storage system: The working power of the electrolyzer mainly follows the change of photovoltaic power generation, realizing the direct coupling of the "generation-use" end, reducing the two conversion losses in the "storage-release" process of energy in the energy storage battery, and improving the overall energy efficiency of the system.

[0159] 4. Simple control logic, easy to implement in engineering: No need for complex power prediction models and optimization algorithms, low computational load, high reliability, easy to implement on existing PLC controllers, embedded controllers and other hardware platforms.

[0160] This invention provides a computer-readable storage medium storing processor-executable computer program instructions. When executed by a processor, the computer program instructions cause the computer to perform any of the power regulation methods for a photovoltaic hydrogen storage system provided in this invention, or to perform the steps in any possible implementation of any of the power regulation methods for a photovoltaic hydrogen storage system provided in this invention.

[0161] Those skilled in the art will understand that the embodiments provided by this invention are merely illustrative. The order in which the steps in the methods of the embodiments are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The order can be adjusted, merged, and deleted according to actual needs. Modules or sub-modules, units or sub-units in the apparatus or system of the embodiments can be merged, divided, and deleted according to actual needs. For example, the division of units is only a logical functional division, and there may be other division methods in actual implementation. For another example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed.

[0162] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a general-purpose hardware platform, and of course, it can also be implemented using hardware. Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This computer program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. It should be understood that the storage medium can be flash memory, hard disk, optical disk, register, magnetic surface memory, removable disk, CD-ROM, random access memory (RAM), read-only memory (ROM), electrically programmable ROM, and electrically erasable programmable ROM, etc.

[0163] It should be noted that the above embodiments are for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can understand that all or part of the processes of the above embodiments can be implemented by modifying the technical solutions described in the embodiments of the present invention, or by making equivalent substitutions for some of the technical features. It is understood that 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, and should be considered as equivalent changes and modifications made based on the embodiments of the present invention, all of which should fall within the scope of the claims of the present invention.

Claims

1. A power regulation method for a photovoltaic hydrogen storage system, characterized in that, include: The output power of the photovoltaic module at the current moment is filtered to obtain the photovoltaic power generation power of the photovoltaic module at the current moment; Based on the relationship between the current state of charge (SOC) value of the energy storage battery and the desired charge operating range of the energy storage battery, the target charge value of the energy storage battery under PI control at the current moment is determined, including: in response to the current SOC value being greater than the maximum value of the desired charge operating range, the difference between the current SOC value and a first preset charge value is calculated to obtain the target charge value at the current moment; in response to the current SOC value being greater than the mean of the charge range and less than or equal to the maximum value, the difference between the current SOC value and a second preset charge value is calculated to obtain the target charge value at the current moment, wherein the mean of the charge range is the average of the maximum and minimum values ​​of the desired charge operating range; in response to the current The state of charge (SOC) value at a given time is equal to the mean of the charge interval, and the SOC value at the current time is determined to be the target charge value at the current time. In response to the SOC value at the current time being greater than or equal to the minimum value of the desired charge working interval and less than the mean of the charge interval, the SOC value at the current time is summed with the second preset charge value to obtain the target charge value at the current time. In response to the SOC value at the current time being less than the minimum value, the SOC value at the current time is summed with the first preset charge value to obtain the target charge value at the current time. Wherein, both the first preset charge value and the second preset charge value are greater than 0, and the first preset charge value is greater than the second preset charge value. The charge difference of the energy storage battery at the current moment is determined based on the difference between the current state of charge value of the energy storage battery and the current target charge value. Based on the charge difference at the current moment, PI control is performed to determine the current working power adjustment value of the electrolytic cell; The target operating power value of the electrolytic cell is determined based on the current photovoltaic power generation and the current operating power adjustment value.

2. The power regulation method for a photovoltaic hydrogen storage system according to claim 1, characterized in that, The step of performing PI control based on the charge difference at the current moment to determine the current operating power adjustment value of the electrolyzer includes: Based on the integral term in the PI control process at the previous moment and the charge difference at the current moment, the integral term in the PI control process at the current moment is determined; Based on the integral term from the previous moment and the charge difference from the current moment, the operating power adjustment value of the electrolytic cell at the current moment is determined. In the PI control process, the initial value of the integral term is zero.

3. The power regulation method for a photovoltaic hydrogen storage system according to claim 2, characterized in that, Determining the integral term in the PI control process at the current moment based on the integral term in the PI control process at the previous moment and the charge difference at the current moment includes: Obtain the product of the charge difference and the integral coefficient at the current moment; The product is summed with the integral term from the previous time step to determine the integral term for the current time step.

4. The power regulation method for a photovoltaic hydrogen storage system according to claim 2, characterized in that, Determining the electrolytic cell's operating power adjustment value at the current moment based on the integral term from the previous moment and the charge difference at the current moment includes: Obtain the product of the charge difference and the scaling factor at the current moment; The operating power adjustment value at the current moment is determined by summing the product with the integral term from the previous moment.

5. The power regulation method for a photovoltaic hydrogen storage system according to any one of claims 1-4, characterized in that, The determination of the target operating power value of the electrolyzer based on the current photovoltaic power generation and the current operating power adjustment value includes: The target operating power value is obtained by adding the photovoltaic power generation power at the current moment to the operating power adjustment value at the current moment.

6. The power regulation method for a photovoltaic hydrogen storage system according to any one of claims 1-4, characterized in that, After determining the target operating power value of the electrolytic cell, the method further includes: gradually adjusting the operating power of the electrolytic cell to the target operating power value during at least one adjustment cycle, including: Obtain the absolute power difference between the actual operating power of the electrolytic cell at the current moment and the target operating power value at the current moment; When the absolute power difference at the current moment is greater than the power change threshold, the sum of the power change threshold and the actual working power at the current moment shall be used as the adjusted working power of the electrolytic cell in the current adjustment cycle. When the absolute power difference at the current moment is less than or equal to the power change threshold, the working power of the electrolytic cell is adjusted to the target working power value.

7. The power regulation method for a photovoltaic hydrogen storage system according to any one of claims 1-4, characterized in that, The step of filtering the output power of the photovoltaic module at the current moment to obtain the photovoltaic power generation of the photovoltaic module at the current moment includes: Obtain the N photovoltaic power generation capacities of the photovoltaic module for the N moments prior to the current moment; Calculate the average of the N photovoltaic power generation capacities and the output power of the photovoltaic module at the current moment to obtain the photovoltaic power generation capacity at the current moment.

8. A photoelectric hydrogen storage system, characterized in that, include: A DC-DC converter and a photovoltaic module, energy storage battery and electrolytic cell connected to the DC-DC converter; The processor, connected to the energy storage battery, the photovoltaic module, and the electrolyzer, is used to acquire the output power of the photovoltaic module, the state of charge value of the energy storage battery, and the operating power of the electrolyzer, and to execute the power regulation method of the photovoltaic hydrogen storage system as described in any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores processor-executable computer program instructions, which, when executed by the processor, cause the computer to perform the power regulation method for the photovoltaic hydrogen storage system as described in any one of claims 1 to 7.

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