Control method and apparatus for hydrogen production system

Abstract

A control method and apparatus for a hydrogen production system. The method comprises: for each electrolytic cell, performing evaluation to obtain energy efficiencies of the electrolytic cell under load currents; for each electrolytic cell, converting the energy efficiencies of the electrolytic cell under the load currents into an energy efficiency value of the electrolytic cell; and ranking the electrolytic cells in descending order according to the energy efficiency values of the electrolytic cells, and performing power distribution on the electrolytic cells on the basis of the ranking. In the present solution, current efficiencies corresponding to load currents are obtained on the basis of bypass currents under the load currents, energy efficiencies corresponding to the load currents are obtained on the basis of the current efficiencies and voltage efficiencies, the energy efficiencies are converted into energy efficiency values, and power distribution is performed on electrolytic cells on the basis of the energy efficiency values, thereby achieving the purpose of controlling the power distribution for electrolytic cells in a hydrogen production system on the basis of accurate energy efficiencies of the electrolytic cells.

Description

A control method and device for a hydrogen production system

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on July 24, 2023, with application number 202310919709.0 and invention name “A control method and device for a hydrogen production system”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of control technology, and in particular to a control method and device for a hydrogen production system. Background Art

[0003] As the demand for hydrogen energy continues to increase and the cost of electricity from new energy sources continues to decrease, the application scenarios of large-scale hydrogen production from new energy sources are becoming more and more extensive.

[0004] In existing hydrogen production systems, power is distributed to each electrolyzer in an average distribution manner without considering the performance of the electrolyzer itself. Alternatively, the voltage efficiency of the electrolyzer is used to represent the energy efficiency of the electrolyzer and power distribution is performed based on the energy efficiency. However, due to the existence of bypass current in the electrolyzer, the voltage efficiency cannot represent the energy efficiency of the entire electrolyzer. Therefore, it is impossible to control the power distribution of each electrolyzer in the hydrogen production system based on the accurate electrolyzer energy efficiency.

[0005] Therefore, how to accurately evaluate and allocate power to each electrolyzer based on the energy efficiency of the electrolyzer is an urgent problem that needs to be solved.

[0006] Summary of the Invention

[0007] In view of this, an embodiment of the present invention provides a control method and device for a hydrogen production system to achieve the purpose of accurately evaluating and allocating power to each electrolyzer based on the energy efficiency of the electrolyzer.

[0008] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0009] A first aspect of an embodiment of the present invention discloses a control method for a hydrogen production system, which is applied to a hydrogen production system composed of an electrolyzer. The method includes:

[0010] For each electrolytic cell, evaluating the energy efficiency of the electrolytic cell under various load currents;

[0011] For each electrolytic cell, converting the energy efficiency of the electrolytic cell under each load current into an energy efficiency value of the electrolytic cell;

[0012] The electrolytic cells are sorted from large to small according to their energy efficiency values, and power is allocated to the electrolytic cells based on the sorting.

[0013] Preferably, evaluating the energy efficiency of each electrolytic cell under various load currents includes:

[0014] For each electrolytic cell, detecting and obtaining the current efficiency of the electrolytic cell under various load currents, and obtaining the voltage efficiency of the electrolytic cell;

[0015] The energy efficiency of the electrolytic cell is evaluated based on the current efficiency and the voltage efficiency.

[0016] Preferably, for each electrolytic cell, detecting and obtaining the current efficiency of the electrolytic cell under various load currents, and obtaining the voltage efficiency of the electrolytic cell, includes:

[0017] For each electrolytic cell, the bypass current flowing through the electrolytic cell bypass loop under each load current is obtained, the ratio of each bypass current to the corresponding load current is used as the current efficiency corresponding to each load current, and the voltage efficiency of the electrolytic cell is obtained.

[0018] Preferably, for each electrolytic cell, converting the energy efficiency of the electrolytic cell under each load current into the energy efficiency value of the electrolytic cell comprises:

[0019] For each electrolytic cell, the energy efficiency of the electrolytic cell under various load currents is weighted or averaged to obtain the energy efficiency value of the electrolytic cell.

[0020] Preferably, it also includes:

[0021] In response to receiving the hydrogen production instruction, based on the order of the energy efficiency values ​​of the electrolyzers from large to small, the electrolyzer that is not currently in operation and has the highest order is controlled to start hydrogen production.

[0022] A second aspect of an embodiment of the present invention discloses a control device for a hydrogen production system, which is applied to a hydrogen production system composed of an electrolyzer. The device includes:

[0023] An evaluation unit, configured to evaluate, for each electrolytic cell, the energy efficiency of the electrolytic cell under various load currents;

[0024] a conversion unit, configured to convert the energy efficiency of the electrolytic cell under various load currents into an energy efficiency value of the electrolytic cell;

[0025] The allocation unit is used to sort the electrolytic cells according to their energy efficiency values ​​from large to small, and allocate power to the electrolytic cells based on the sorting.

[0026] Preferably, the evaluation unit includes:

[0027] a detection subunit, configured to detect, for each electrolytic cell, the current efficiency of the electrolytic cell under various load currents, and obtain the voltage efficiency of the electrolytic cell;

[0028] An evaluation subunit is configured to evaluate the energy efficiency of the electrolytic cell based on the current efficiency and the voltage efficiency.

[0029] Preferably, the detection subunit is specifically used for:

[0030] For each electrolytic cell, the bypass current flowing through the electrolytic cell bypass loop under each load current is obtained, the ratio of each bypass current to the corresponding load current is used as the current efficiency corresponding to each load current, and the voltage efficiency of the electrolytic cell is obtained.

[0031] Preferably, the conversion unit is specifically used to:

[0032] For each electrolytic cell, the energy efficiency of the electrolytic cell under various load currents is weighted or averaged to obtain the energy efficiency value of the electrolytic cell.

[0033] Preferably, it also includes:

[0034] The response unit is used to respond to the hydrogen production instruction and control the electrolyzer that is not currently in working state and has the highest ranking to start hydrogen production based on the order of the energy efficiency values ​​of the electrolyzers from large to small.

[0035] Based on the above-mentioned embodiment of the present invention, a control method and device for a hydrogen production system are provided. For each electrolyzer, the energy efficiency of the electrolyzer under each load current is evaluated and obtained; for each electrolyzer, the energy efficiency of the electrolyzer under each load current is converted into an energy efficiency value of the electrolyzer; the electrolyzers are sorted from large to small according to their energy efficiency values, and power is allocated to each electrolyzer based on the sorting. In this solution, the energy efficiency corresponding to each load current is evaluated and obtained, and the energy efficiency is converted into an energy efficiency value. Power is allocated to each electrolyzer based on the energy efficiency value, thereby achieving the purpose of controlling the power allocation of each electrolyzer in the hydrogen production system based on accurate electrolyzer energy efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0037] FIG1 is an architecture diagram of a hydrogen production system disclosed in an embodiment of the present invention;

[0038] FIG2 is a diagram of an equivalent electrical model of an electrolytic cell disclosed in an embodiment of the present invention;

[0039] FIG3 is a flow chart of a control method for a hydrogen production system disclosed in an embodiment of the present invention;

[0040] FIG4 is a structural diagram of a control device for a hydrogen production system disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention, in conjunction with the accompanying drawings. It should be understood that the described embodiments are merely a portion of the embodiments of the present invention, and not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0042] In this application, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0043] As can be seen from the background technology, in the existing hydrogen production system, the power distribution of each electrolyzer is carried out in an average distribution manner without taking into account the performance of the electrolyzer itself. Alternatively, the voltage efficiency of the electrolyzer is used to represent the energy efficiency of the electrolyzer and power distribution is carried out based on the energy efficiency. However, due to the existence of bypass current in the electrolyzer, the voltage efficiency cannot represent the energy efficiency of the entire electrolyzer. Therefore, it is impossible to control the power distribution of each electrolyzer in the hydrogen production system based on the accurate electrolyzer energy efficiency.

[0044] Therefore, an embodiment of the present invention discloses a control method for a hydrogen production system. In this scheme, the bypass current under each load current is obtained and based on it, the current efficiency corresponding to each load current is obtained, the energy efficiency corresponding to each load current is obtained based on the current efficiency and voltage efficiency, and the energy efficiency is converted into an energy efficiency value. Based on the energy efficiency value, power is distributed to each electrolyzer, so as to achieve the purpose of controlling the power distribution of each electrolyzer in the hydrogen production system based on accurate electrolyzer energy efficiency.

[0045] As shown in FIG1 , which is an architecture diagram of a hydrogen production system disclosed in an embodiment of the present invention, the hydrogen production system includes: hydrogen production power supplies 1 to N, electrolyzers 1 to N, and a gas-liquid separation and purification unit.

[0046] Among them, one hydrogen production power supply corresponds to a different electrolyzer, multiple electrolyzers correspond to the same gas-liquid separation and purification unit, hydrogen production power supplies 1 to N are connected to corresponding electrolyzers 1 to N respectively, electrolyzers 1 to N are connected to the gas-liquid separation and purification unit, and N is a positive integer.

[0047] Specifically, an electrolytic cell includes multiple chambers. Taking one chamber as an example, as shown in Figure 2, it is an equivalent electrical model diagram of an electrolytic cell disclosed in an embodiment of the present invention, wherein sub-diagrams a and b of Figure 2 respectively show two different operating conditions of the equivalent electrical model of the electrolytic cell.

[0048] The electrolytic cell consists of a bypass circuit and an electrolysis circuit in parallel. in is the input current, I r is the bypass current, and I1 in Figure 2 b is the electrolysis current flowing through the electrolysis circuit.

[0049] In the bypass circuit, R shunt It is the electrolyte path impedance, that is, the equivalent bypass impedance of the bypass circuit.

[0050] In the electrolysis circuit, Urev is the reversible electrolysis voltage, Re is the diaphragm electrode equivalent impedance, ηact is the electrode overpotential, and Ca is the double-layer capacitance. The reversible electrolysis voltage, diaphragm electrode equivalent impedance, electrode overpotential, and double-layer capacitance are equivalent to a small chamber.

[0051] In one embodiment, the electrolysis circuit in the electrolytic cell may include a plurality of chambers. Assume that when the electrolysis circuit includes M chambers, the electrolysis voltage of the electrolytic cell is equal to M*Urev.

[0052] Specifically, FIG2 a shows the working condition of the electrolytic cell when it is not working properly, that is, when the cell voltage is lower than the reversible electrolysis voltage Urev, the entire cell cannot be turned on, and the input current I in All flows through the bypass resistor R shunt , at this time the cell voltage is the bypass voltage drop.

[0053] Specifically, FIG2 b shows the working condition of the electrolyzer when it is working normally. When the cell voltage is greater than the reversible electrolysis voltage Urev, the cell starts electrolysis and produces hydrogen normally. The input current I in Shunt to I r and I1, flow through the bypass circuit and electrolysis circuit respectively.

[0054] Based on the hydrogen production system shown in FIG1 and the equivalent electrical model of the electrolyzer shown in FIG2 , FIG3 is a flow chart of a control method for a hydrogen production system disclosed in an embodiment of the present invention. The method is applied to a hydrogen production system composed of an electrolyzer including the hydrogen production system shown in FIG1 . The method mainly includes the following steps:

[0055] Step S301: For each electrolytic cell, evaluate and obtain the energy efficiency of the electrolytic cell under various load currents.

[0056] In step S301, for each electrolytic cell, the current efficiency of the electrolytic cell under various load currents is detected, and the voltage efficiency of the electrolytic cell is obtained. The energy efficiency of the electrolytic cell is evaluated based on the current efficiency and voltage efficiency. For the specific evaluation method, please refer to steps S1 to S2.

[0057] Step S1: for each electrolytic cell, obtain the bypass current flowing through the electrolytic cell bypass loop under each load current, and use the ratio of each bypass current to the corresponding load current as the current efficiency corresponding to each load current.

[0058] In one embodiment, before executing step S1, it is determined whether the status indicators such as the pressure and temperature of the electrolytic cell are in a normal working state. If so, step S1 is executed; otherwise, the status indicators such as the pressure and temperature of the electrolytic cell are continuously detected. When the status indicators return to normal, step S301 is executed.

[0059] In step S1, each load current is the total input current of the electrolytic cell at different working loads, that is, I in Input current.

[0060] It should be noted that when the workload increases from small to large, the load current also gradually increases.

[0061] The specific implementation process of step S1 mainly includes the following steps:

[0062] Step S11: Detect and obtain the equivalent bypass impedance of each electrolytic cell.

[0063] In step S11, in order to detect the equivalent bypass impedance, the electrolytic cell needs to be in a condition where the bypass circuit is conductive and the electrolysis circuit is not conductive, and the voltage of the electrolytic cell is required to be less than the electrolysis voltage, that is, the condition shown in sub-graph a of FIG2 .

[0064] If the electrolytic cell contains M small chambers, the sum of the reversible electrolysis voltages of each small chamber is equal to the electrolysis voltage of the electrolytic cell, that is, the voltage of the electrolytic cell is required to be less than M*reversible electrolysis voltage, so that the electrolytic cell is in a bypass circuit conductive state and the electrolysis circuit is in a non-conductive state, so as to perform the equivalent bypass impedance detection.

[0065] The detection method is: under the condition that the voltage of the electrolytic cell is less than M*reversible electrolysis voltage, IV scanning is performed to obtain an IV curve. The IV curve can represent the corresponding relationship between the input voltage and input current of the electrolytic cell. According to the corresponding relationship between the input voltage and input current of the electrolytic cell, the equivalent bypass impedance is calculated.

[0066] The specific calculation method is: use any input voltage less than M*reversible electrolysis voltage divided by the corresponding input current.

[0067] or,

[0068] The input voltages less than M*reversible electrolysis voltage are divided by the corresponding input currents to obtain the respective equivalent bypass impedances, and then the average value is taken.

[0069] Step S12: For each electrolytic cell, obtain the corresponding load voltage of the electrolytic cell under each load current.

[0070] In step S12, when different workloads are applied to the electrolytic cell and different load currents flow through the electrolytic cell, the load voltage corresponding to each load current of the electrolytic cell is detected.

[0071] Step S13: Based on each load voltage and the equivalent bypass impedance, a bypass current flowing through the electrolytic cell bypass loop under each load current is obtained.

[0072] In step S13, since the bypass loop and the electrolysis loop are in parallel, the load voltage is the voltage of the bypass loop. Each load voltage is divided by the equivalent bypass impedance to obtain the bypass current corresponding to each load voltage. Based on the correspondence between each load voltage and each load current, the bypass current flowing through the electrolytic cell bypass loop under each load current is further obtained.

[0073] Step S14: taking the ratio of each bypass current to the corresponding load current as the current efficiency corresponding to each load current.

[0074] Step S2: converting the current efficiency and voltage efficiency of the electrolytic cell at each load current to obtain the energy efficiency of the electrolytic cell at each load current.

[0075] In step S2 , the voltage efficiency includes the ratio of the thermal neutral voltage to the average voltage of each cell, wherein the thermal neutral voltage is generally 1.48V, and the average voltage of each cell is the load voltage corresponding to the load current divided by the number of cells.

[0076] It should be noted that if the energy efficiency of the electrolytic cell is expressed by voltage efficiency, that is, voltage efficiency η = U HHV / U cell_avg , where U HHV Refers to the thermal neutral voltage, generally 1.48V, U cell_avgIt refers to the average cell voltage of the electrolytic cell. Due to the existence of the actual electrolytic cell bypass current (leakage current), the current efficiency is less than 1, and it changes with the current density (that is, it changes with the change of the electrolytic cell workload). A high voltage efficiency does not necessarily mean a high electrolytic cell energy efficiency. Therefore, it is necessary to combine the voltage efficiency and current efficiency to obtain the energy efficiency of the electrolytic cell.

[0077] In step S2, the specific process of the conversion process is:

[0078] The formula: energy efficiency = voltage efficiency * current efficiency is used for conversion, that is, the product of the current efficiency and voltage efficiency corresponding to the electrolytic cell at each load current is used as the energy efficiency of the electrolytic cell at each load current.

[0079] Step S302: for each electrolytic cell, convert the energy efficiency of the electrolytic cell under each load current into the energy efficiency value of the electrolytic cell.

[0080] In step S302 , one electrolytic cell corresponds to multiple energy efficiencies, and each energy efficiency needs to be converted into an energy efficiency value uniquely corresponding to the electrolytic cell, that is, multiple energy efficiencies are converted into one energy efficiency value.

[0081] In the specific implementation process of step S302, the average value of the energy efficiency of the electrolytic cell under various load currents is used as the energy efficiency value of the electrolytic cell.

[0082] For example, if the load current is expressed as a percentage, the current efficiency at a 30% load current is 60%, the current efficiency at a 50% load current is 70%, the current efficiency at a 70% load current is 90%, the current efficiency at a 90% load current is 88%, and the current efficiency at a 100% load current is 85%. On average, the energy efficiency value of the electrolyzer can be expressed as: (60% + 70% + 90% + 88% + 85%) / 5 = 0.786

[0083] or,

[0084] The energy efficiency value of the electrolytic cell is obtained by weighted processing based on the energy efficiency of the electrolytic cell under various load currents.

[0085] Specifically, weights are set for load currents of different sizes, and a weighted average calculation is performed based on the set weights to obtain the energy efficiency value of the electrolyzer.

[0086] Step S303: sorting the electrolytic cells according to their energy efficiency values ​​from large to small, and allocating power to the electrolytic cells based on the sorting.

[0087] In step S303, the electrolytic cells are prioritized from large to small according to their energy efficiency values. Electrolytic cells with high energy efficiency values ​​have high hydrogen production efficiency, so more power is allocated to them to produce more hydrogen.

[0088] In one embodiment, after the electrolyzers are prioritized from large to small according to their energy efficiency values, in response to receiving a hydrogen production instruction, based on the order of the energy efficiency values ​​of the electrolyzers from large to small, the electrolyzer that is not currently in operation and has the highest order is controlled to start hydrogen production.

[0089] In one embodiment, after the electrolytic cells are prioritized from large to small according to their energy efficiency values, the electrolytic cells with high priorities are given priority and are set to work for a longer time. The electrolytic cells with low energy efficiency values ​​have low working priorities and are set to work for a shorter time than those with high priorities. In this way, the life of all electrolytic cells in the entire station can be balanced, ensuring the consistency of the operating life of the electrolytic cells in the entire station.

[0090] Based on the control method of a hydrogen production system disclosed in the above-mentioned embodiment of the present invention, for each electrolyzer, the bypass current flowing through the electrolyzer bypass loop under each load current is obtained, and the ratio of each bypass current to the corresponding load current is respectively used as the current efficiency corresponding to each load current. The current efficiency and voltage efficiency corresponding to the electrolyzer under each load current are converted to obtain the energy efficiency of the electrolyzer under each load current, and the energy efficiency of the electrolyzer under each load current is converted into the energy efficiency value of the electrolyzer. The electrolyzers are sorted from large to small according to their energy efficiency values, and power is allocated to the electrolyzers based on the sorting. In this solution, the current efficiency corresponding to each load current is obtained based on the bypass current under each load current, the energy efficiency corresponding to each load current is obtained based on the current efficiency and voltage efficiency, and the energy efficiency is converted into the energy efficiency value. Power is allocated to the electrolyzers based on the energy efficiency value, so as to achieve the purpose of controlling the power allocation of each electrolyzer in the hydrogen production system based on accurate electrolyzer energy efficiency.

[0091] Based on the control method of a hydrogen production system disclosed in the embodiment of the present invention, FIG4 is a structural diagram of a control device of a hydrogen production system disclosed in the embodiment of the present invention. The device is applied to a hydrogen production system composed of an electrolyzer including the hydrogen production system shown in FIG1 . The device includes:

[0092] The evaluation unit 401 is configured to evaluate the energy efficiency of each electrolytic cell under various load currents.

[0093] In one embodiment, the evaluation unit 401 includes: a detection subunit and an evaluation subunit.

[0094] The acquisition module is used for detecting the subunit, and is used for detecting and obtaining the current efficiency of each electrolytic cell under various load currents, and obtaining the voltage efficiency of the electrolytic cell.

[0095] In one embodiment, the detection subunit includes:

[0096] The detection submodule is used to detect and obtain the equivalent bypass impedance of each electrolytic cell.

[0097] The acquisition submodule is used to obtain, for each electrolytic cell, the load voltage corresponding to the electrolytic cell under each load current and the voltage efficiency of the electrolytic cell.

[0098] The calculation submodule is used to obtain the bypass current flowing through the electrolyzer bypass loop under each load current based on each load voltage and the equivalent bypass impedance.

[0099] The ratio submodule is used to use the ratio of each bypass current to the corresponding load current as the current efficiency corresponding to each load current.

[0100] In one embodiment, the detection submodule is specifically used to: for each electrolytic cell, under the condition that the voltage of the electrolytic cell is less than the electrolysis voltage, obtain the corresponding relationship between the input voltage and the input current of the electrolytic cell through IV scanning, the electrolysis voltage includes the sum of the reversible electrolysis voltages of each chamber, and obtain the equivalent bypass impedance based on the input voltage of the electrolytic cell and the corresponding input current.

[0101] The evaluation subunit is used to evaluate the energy efficiency of the electrolyzer based on the current efficiency and voltage efficiency.

[0102] In one embodiment, the evaluation subunit is specifically used to: use the average value of the energy efficiency of the electrolytic cell under various load currents as the energy efficiency value of the electrolytic cell, or perform weighted calculation based on the energy efficiency of the electrolytic cell under various load currents to obtain the energy efficiency value of the electrolytic cell.

[0103] Among them, the voltage efficiency is the ratio of the thermal neutral voltage to the average voltage of each cell, and the thermal neutral voltage is generally 1.48V.

[0104] The conversion unit 402 is configured to convert the energy efficiency of each electrolytic cell under various load currents into an energy efficiency value of the electrolytic cell.

[0105] Specifically, for each electrolytic cell, the energy efficiency of the electrolytic cell under various load currents is weighted or averaged to obtain the energy efficiency value of the electrolytic cell.

[0106] The allocation unit 403 is configured to sort the electrolytic cells according to their energy efficiency values ​​from large to small, and allocate power to the electrolytic cells based on the sorting.

[0107] In one embodiment, the control device of the hydrogen production system also includes: a response unit, which is used to respond to receiving a hydrogen production instruction and control the electrolyzer that is not currently in working state and has the highest ranking to start hydrogen production based on the sorting of each electrolyzer according to energy efficiency value from large to small.

[0108] Based on the control device for a hydrogen production system disclosed in the above-mentioned embodiment of the present invention, for each electrolyzer, the bypass current flowing through the electrolyzer bypass loop under each load current is obtained, and the ratio of each bypass current to the corresponding load current is respectively used as the current efficiency corresponding to each load current. The current efficiency and voltage efficiency corresponding to the electrolyzer under each load current are converted to obtain the energy efficiency of the electrolyzer under each load current. The energy efficiency of the electrolyzer under each load current is converted into an energy efficiency value of the electrolyzer. The electrolyzers are sorted from large to small according to their energy efficiency values, and power is allocated to the electrolyzers based on the sorting. In this solution, the current efficiency corresponding to each load current is obtained based on the bypass current under each load current, the energy efficiency corresponding to each load current is obtained based on the current efficiency and voltage efficiency, and the energy efficiency is converted into an energy efficiency value. Power is allocated to the electrolyzers based on the energy efficiency value, thereby achieving the purpose of controlling the power allocation of each electrolyzer in the hydrogen production system based on accurate electrolyzer energy efficiency.

[0109] Each embodiment in this specification is described in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple. For relevant parts, refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without expending creative work.

[0110] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0111] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a hydrogen production system, characterized in that: Applied to a hydrogen production system consisting of an electrolyzer, the method comprises: For each electrolytic cell, evaluating the energy efficiency of the electrolytic cell under various load currents; For each electrolytic cell, converting the energy efficiency of the electrolytic cell under each load current into an energy efficiency value of the electrolytic cell; The electrolytic cells are sorted from large to small according to their energy efficiency values, and power is allocated to the electrolytic cells based on the sorting.

2. The method according to claim 1, characterized in that For each electrolytic cell, evaluating the energy efficiency of the electrolytic cell under various load currents includes: For each electrolytic cell, the current efficiency of the electrolytic cell under each load current is detected, and the voltage efficiency of the electrolytic cell is obtained; The energy efficiency of the electrolytic cell is evaluated based on the current efficiency and the voltage efficiency.

3. The method according to claim 2, characterized in that For each electrolytic cell, detecting and obtaining the current efficiency of the electrolytic cell under various load currents, and obtaining the voltage efficiency of the electrolytic cell, comprises: For each electrolytic cell, the bypass current flowing through the electrolytic cell bypass loop under each load current is obtained, the ratio of each bypass current to the corresponding load current is used as the current efficiency corresponding to each load current, and the voltage efficiency of the electrolytic cell is obtained.

4. The method according to claim 1, characterized in that: For each electrolytic cell, converting the energy efficiency of the electrolytic cell under each load current into the energy efficiency value of the electrolytic cell comprises: For each electrolytic cell, the energy efficiency of the electrolytic cell under each load current is weighted or averaged to obtain the energy efficiency value of the electrolytic cell.

5. The method according to any one of claims 1 to 4, characterized in that: Also includes: In response to receiving the hydrogen production instruction, based on the order of the energy efficiency values ​​of the electrolyzers from large to small, the electrolyzer that is not currently in operation and has the highest order is controlled to start hydrogen production.

6. A control device for a hydrogen production system, characterized in that: Applicable to a hydrogen production system consisting of an electrolyzer, the device comprises: An evaluation unit, configured to evaluate, for each electrolytic cell, the energy efficiency of the electrolytic cell under various load currents; A conversion unit is used to convert the energy efficiency of the electrolytic cell under various load currents into the energy efficiency of the electrolytic cell under various load currents. Energy efficiency value of the solution tank; The allocation unit is used to sort the electrolytic cells according to their energy efficiency values ​​from large to small, and allocate power to the electrolytic cells based on the sorting.

7. The device according to claim 6, characterized in that The evaluation unit comprises: A detection subunit, for detecting, for each electrolytic cell, obtaining the current efficiency of the electrolytic cell under various load currents, and obtaining the voltage efficiency of the electrolytic cell; An evaluation subunit is used to evaluate the energy efficiency of the electrolytic cell based on the current efficiency and the voltage efficiency.

8. The device according to claim 7, characterized in that The detection subunit is specifically used for: For each electrolytic cell, the bypass current flowing through the electrolytic cell bypass loop under each load current is obtained, the ratio of each bypass current to the corresponding load current is used as the current efficiency corresponding to each load current, and the voltage efficiency of the electrolytic cell is obtained.

9. The device according to claim 6, characterized in that The conversion unit is specifically used for: For each electrolytic cell, the energy efficiency of the electrolytic cell under each load current is weighted or averaged to obtain the energy efficiency value of the electrolytic cell.

10. The device according to any one of claims 6 to 9, characterized in that: Also includes: The response unit is used to respond to the receipt of the hydrogen production instruction, and based on the order of the energy efficiency values ​​of the electrolyzers from large to small, control the electrolyzer that is not currently in operation and has the highest order to start hydrogen production.

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