Alkaline hydrogen production system, control method, medium and product

Abstract

The invention relates to the technical field of water electrolysis hydrogen production, and discloses an alkaline hydrogen production system, a control method, a medium and a product. The power supply module is electrically connected with the electrolytic bath and the auxiliary system; the auxiliary system comprises a control subsystem, a gas-liquid separation subsystem and a water and alkali supplementing subsystem. The water-alkali supplementing subsystem is connected with an electrolytic bath pipeline, the gas-liquid separation subsystem is connected with the electrolytic bath pipeline, and the control subsystem is in signal connection with the gas-liquid separation subsystem, the water-alkali supplementing subsystem and the electrolytic bath; and a diaphragm in the electrolytic bath adopts an organic-inorganic composite diaphragm. Hydrogen is prevented from transversely penetrating to the anode side through the organic-inorganic composite diaphragm, it is determined that the wind-light power can break through the limitation of 20% of the rated power of the electrolytic cell, shutdown of the electrolytic cell cannot be caused, and the electrolytic cell can meet any fluctuation of the wind-light power.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen production by electrolysis of water, and in particular to an alkaline hydrogen production system, a control method, a medium and a product. Background Art

[0002] The electrolysis water hydrogen production technology mainly includes alkaline water electrolysis water hydrogen production technology, proton exchange membrane water electrolysis water hydrogen production technology, solid oxide water electrolysis water hydrogen production technology and anion exchange membrane water electrolysis water hydrogen production technology. Among the existing water electrolysis water hydrogen production technologies, alkaline water electrolysis water hydrogen production technology is relatively mature, the process is relatively simple, and the cost is relatively low, but the bottleneck is that the working current density is relatively low, the electrolyzer efficiency is relatively low, and the load operation range of the electrolyzer is only 20%-100%. This is because if the power output power is lower than 20% of the rated power of the electrolyzer, the oxygen-hydrogen index of the electrolyzer will exceed the threshold, which will destroy the balance of the electrolysis reaction, and the system must be shut down. In order to achieve green hydrogen production, the power source of the electrolyzer often uses renewable energy such as wind and solar power, and the output power of renewable energy such as wind and solar power is unstable. The wind and solar power will often be lower than 20% of the rated power of the electrolyzer, which causes the problem of frequent shutdown of the electrolyzer, and then the frequent shutdown of the electrolyzer causes damage to the electrolyzer electrodes and diaphragms, which accelerates the reduction of its service life. Therefore, how to make the electrolyzer able to meet the arbitrary fluctuations of wind and solar power is an urgent problem to be solved. Summary of the invention

[0003] In view of this, the present invention provides an alkaline hydrogen production system, control method, medium and product to solve the problem of frequent shutdown of the electrolyzer due to arbitrary fluctuations in wind and solar power during alkaline hydrogen production.

[0004] In a first aspect, the present invention provides an alkaline hydrogen production system, comprising: a power module, an electrolyzer and an auxiliary system; the power module is electrically connected to the electrolyzer and the auxiliary system respectively; the auxiliary system comprises a control subsystem, a gas-liquid separation subsystem and a water-alkali replenishment subsystem; the water-alkali replenishment subsystem is connected to the electrolyzer pipeline, the gas-liquid separation subsystem is connected to the electrolyzer pipeline, and the control subsystem is signal-connected to the gas-liquid separation subsystem, the water-alkali replenishment subsystem and the electrolyzer respectively; the diaphragm in the electrolyzer adopts an organic-inorganic composite diaphragm.

[0005] In some optional embodiments, the power supply module includes: a photovoltaic power supply, a wind power supply, a first DC transformer module, a rectifier module, a power terminal, a second DC transformer module and a battery; the photovoltaic power supply is electrically connected to the first DC transformer module; the wind power supply is electrically connected to the rectifier module; the first DC transformer module and the rectifier module are both electrically connected to the power terminal; the power terminal is electrically connected to the battery; the battery is electrically connected to the electrolytic cell; the battery is also electrically connected to the second DC transformer module; the second DC transformer module is electrically connected to the auxiliary system.

[0006] In some optional embodiments, the power module also includes a first switch; the power terminal is also electrically connected to the electrolytic cell, and the first switch is arranged between the power terminal and the line of the electrolytic cell; the control subsystem is also signal-connected to the first switch, the battery and the power terminal.

[0007] In some optional embodiments, the battery includes a plurality of battery cells, and some or all of the battery cells in the battery are connected in parallel so that the output voltage of the battery is no more than 500V.

[0008] In a second aspect, the present invention provides a control method for an alkaline hydrogen production system, which is applied to a control subsystem, including: starting a power module to power on an electrolyzer; starting a gas-liquid separation subsystem to separate the hydrogen produced by the electrolyzer; and shutting down when it is detected that the power output from the power module to the electrolyzer is lower than a preset lower limit of the rated power of the electrolyzer, wherein the preset lower limit is a percentage of the rated power of the electrolyzer calculated by an organic-inorganic composite diaphragm in the electrolyzer, which can make the hydrogen in oxygen index exceed the hydrogen in oxygen threshold.

[0009] In some optional embodiments, the starting power module powers on the electrolytic cell, including: collecting the output power of the power terminal; comparing the output power with the rated power of the battery; when the output power is greater than the rated power, closing the first switch; when the output power is less than or equal to the rated power, opening the first switch.

[0010] In some optional embodiments, the method further includes: when the first switch is closed, determining whether the output power is greater than a first preset power threshold; when the output power is greater than the first preset power threshold, increasing the proportion of power output from the power terminal to the battery; determining whether the output power is less than a second preset power threshold; when the output power is less than the second preset power threshold, reducing the proportion of power output from the power terminal to the battery and increasing the power output from the battery to the electrolyzer, the second preset power threshold being less than the first preset power threshold.

[0011] In some optional embodiments, the method further includes: detecting the quality of electrolyte in the electrolytic cell; when the quality of the electrolyte is lower than a preset quality threshold, starting the water and alkali replenishment subsystem to add electrolyte to the electrolytic cell.

[0012] In a third aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to cause a computer to execute the method of the second aspect or any corresponding embodiment thereof.

[0013] In a fourth aspect, the present invention provides a computer program product, comprising computer instructions for causing a computer to execute the method of the second aspect or any corresponding embodiment thereof.

[0014] The technical solution provided by the present invention has the following advantages:

[0015] (1) The organic-inorganic composite membrane is an organic-inorganic porous membrane with a pore size of only 100 nm, which can prevent hydrogen from penetrating horizontally to the anode side. The pore size and porosity of the composite membrane determine its ability to prevent gas penetration. The smaller the pore size, the better the gas blocking ability, thereby preventing the hydrogen index in oxygen from exceeding the threshold, and further determining that the wind and solar power can break through the 20% limit of the rated power of the electrolyzer. Electrolyzing water with lower wind and solar power will not cause the hydrogen index in oxygen to exceed the threshold, thereby not causing the electrolyzer to shut down, allowing the electrolyzer to meet any fluctuations in wind and solar power, thereby significantly improving the life of the electrolyzer.

[0016] (2) The output ends of the first DC transformer module and the rectifier module are connected in parallel through the power terminal, and as a voltage regulator, the voltage levels of the two inputs are modulated to be the same. A battery is also provided at the output end of the power terminal, and the battery is directly electrically connected to the electrolyzer, and the battery is electrically connected to the auxiliary system through the second DC transformer module. On the one hand, the battery stores the electric energy of the photovoltaic power supply and the wind power supply, and as long as the battery has power, it can output a stable voltage and current, thereby avoiding the problem of frequent fluctuations in the output voltage of the photovoltaic power supply and the wind power supply, and reducing the problem of unstable power of the electrolyzer. On the other hand, the high voltage output by the battery is adjusted to a low voltage output through the second DC transformer module, and the alkali liquid pump, pneumatic valve and other components in the auxiliary system are directly powered, ensuring that the low-voltage accessories of the alkaline water electrolysis hydrogen production system can be used.

[0017] (3) The present invention redesigns the battery, taking into account that the battery is often composed of multiple cells. Therefore, according to the voltage requirements of the electrolytic cell, some or all of the cells in the battery are arranged in parallel. The parallel connection can increase the current output of the overall battery circuit and reduce the voltage.

[0018] (4) The parallel connection method of batteries allows most of the electricity from photovoltaic power sources and wind power sources to provide power for the electrolyzer, and a small amount of electricity is used to charge the batteries. When the power of the photovoltaic power sources and wind power sources fluctuates and causes insufficient power for the electrolyzer, the batteries can be used to supplement the discharge, thereby improving the utilization rate of wind and solar power. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 is a structural schematic diagram of an alkaline hydrogen production system according to an embodiment of the present invention;

[0021] Figure 2 is another structural schematic diagram of an alkaline hydrogen production system according to an embodiment of the present invention;

[0022] Figure 3 is another structural schematic diagram of an alkaline hydrogen production system according to an embodiment of the present invention;

[0023] Figure 4 It is a flow chart of a control method of an alkaline hydrogen production system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0025] According to an embodiment of the present invention, an alkaline hydrogen production system is provided, such as Figure 1 As shown, it includes: power module, electrolyzer and auxiliary system;

[0026] Among them, the power module is electrically connected to the electrolytic cell and the auxiliary system respectively; the auxiliary system includes a control subsystem, a gas-liquid separation subsystem, and a water-alkali replenishing subsystem; the water-alkali replenishing subsystem is connected to the electrolytic cell pipeline, the gas-liquid separation subsystem is connected to the electrolytic cell pipeline, and the control subsystem is respectively connected to the gas-liquid separation subsystem, the water-alkali replenishing subsystem and the electrolytic cell signal; the diaphragm in the electrolytic cell adopts an organic-inorganic composite diaphragm.

[0027] Specifically, alkaline water electrolysis is a common water electrolysis hydrogen production technology, and its basic principle is to decompose water into hydrogen and oxygen by electrolyzing water. In the process of alkaline water electrolysis hydrogen production, alkaline electrolytes (such as potassium hydroxide or sodium hydroxide) are usually used as electrolytes to provide ionic conductivity. The alkaline hydrogen production system mainly includes three parts, namely a power module, an electrolyzer and an auxiliary system. The power module is used to power the electrolyzer. In the embodiment of the present invention, the power module refers to a circuit module for outputting wind and solar power, which usually includes components such as a transformer; the electrolyzer is used for electrolysis reaction; the auxiliary system refers to auxiliary components other than the electrolysis reaction, which usually include a control subsystem, a gas-liquid separation subsystem, a water-alkali supplement subsystem, a purification subsystem, a cooling and drying subsystem, and accessory components installed in the above subsystems.

[0028] Among them, the control subsystem includes but is not limited to the hydrogen production control system and the PLC control cabinet, which are used to monitor the temperature, pressure, flow, gas purity, etc. in the electrolyzer in real time; the gas-liquid separation subsystem includes but is not limited to the gas-liquid separation tank, the droplet collector, and the gas cooler, which are used to separate hydrogen and oxygen from the alkali solution respectively; the purification system is used to purify the hydrogen gas; the water-alkali replenishment subsystem may include an alkali solution tank, an alkali solution filter, an alkali solution circulation pump, a water replenishment pump, a water tank, etc., which are used to replenish the alkali solution electrolyte and water; the cooling and drying subsystem includes a dryer, a heat exchanger, and a cooler, which are used to cool down or cool the gas; the accessories refer to the various sensors and pipe valves in the above subsystems.

[0029] The electrolytic cell is a component used to inject alkaline electrolyte and perform the process of electrolyzing water, including plates and frames, diaphragms, electrodes, gaskets and other structures. The specific structure of the electrolytic cell belongs to the prior art and will not be repeated here. Among them, the main function of the diaphragm is to prevent the mixing of hydrogen and oxygen. For alkaline electrolytic cells, qualified diaphragms should meet the following requirements: isolate gas molecules but allow electrolyte ions to pass through; be resistant to corrosion by high-concentration alkaline solutions and withstand the impact of electrolytes and generated gases for a long time; have a porosity as high as possible to reduce surface resistance, and be chemically stable under electrolysis temperature and alkaline conditions; raw materials are easily available, non-toxic, and pollution-free, and waste is easy to handle.

[0030] At present, the commonly used diaphragm in related technologies is polyphenylene sulfide cloth (PPS). However, because the ability of polyphenylene sulfide cloth to block the cathode hydrogen from penetrating horizontally to the anode oxygen is weak, it is agreed in engineering that when the hydrogen-in-oxygen index (hydrogen content / oxygen content) is greater than a threshold value (usually 2%), the system must be shut down, otherwise the balance of the electrolysis reaction will be destroyed. When the hydrogen-in-oxygen index exceeds the threshold value, the rated power of the electrolyzer is often around 20%. Therefore, the related technology will control the system to shut down after the load of the electrolyzer is lower than 20%.

[0031] In an embodiment of the present invention, the diaphragm material adopts an organic-inorganic composite diaphragm. As a leader in new diaphragm materials, the organic-inorganic composite diaphragm has the unique advantage of perfectly combining organic and inorganic substances to form excellent isolation and mechanical properties. The organic-inorganic composite diaphragm is an organic-inorganic porous diaphragm with a pore size of only 100nm, which can block hydrogen from penetrating horizontally to the anode side. The pore size and porosity of the composite membrane determine its ability to block gas penetration. The smaller the pore size, the better the gas blocking ability, thereby blocking the hydrogen index in oxygen from exceeding the threshold, and then determining that the wind and solar power can break through the 20% limit of the rated power of the electrolyzer. Electrolyzing water with lower wind and solar power will not cause the hydrogen index in oxygen to exceed the threshold (for example, the load lower limit can break through 5%), so that the electrolyzer will not be shut down, so that the electrolyzer can meet any fluctuations in wind and solar power, thereby significantly improving the life of the electrolyzer.

[0032] As shown in the following table, there are comparative parameters of organic-inorganic composite membranes and organic membranes.

[0033]

[0034]

[0035] like Figure 2 As shown, in some optional implementations, the power module provided by the present invention includes: a photovoltaic power source, a wind power source, a first DC transformer module, a rectifier module, a power terminal, a second DC transformer module and a battery;

[0036] The photovoltaic power source is electrically connected to the first DC transformer module; the wind power source is electrically connected to the rectifier module; the first DC transformer module and the rectifier module are both electrically connected to the power terminal; the power terminal is electrically connected to the battery; the battery is electrically connected to the electrolytic cell; the battery is also electrically connected to the second DC transformer module; the second DC transformer module is electrically connected to the auxiliary system.

[0037] Specifically, the photovoltaic power supply is a power supply that collects solar power through photovoltaic modules and outputs direct current, and the wind power supply drives the generator to generate electricity through the blades and outputs alternating current. Based on this, the photovoltaic power supply adjusts the voltage through the first DC transformer module, the first DC transformer module is a DC / DC converter, and the wind power supply rectifies the alternating current into direct current and adjusts the voltage through the rectifier module. Because the output voltage of wind power is generally an AC 10kV voltage, the photovoltaic output DC voltage, and the voltage depends on the number of photovoltaic modules, the photovoltaic output does not match the wind power output voltage. In the embodiment of the present invention, the output ends of the first DC transformer module and the rectifier module are connected in parallel through the power terminal, as a voltage regulator, and the voltage levels of the two inputs are modulated to be the same, thereby improving the reliability of the subsequent circuit power supply. In some optional implementations, the power terminal includes at least two connecting wires, so that the output ends of the first DC transformer module and the rectifier module are connected in parallel, and a resistor element can also be added in the parallel circuit according to the actual application, which is not specifically limited in this embodiment.

[0038] In addition, the embodiment of the present invention also provides a battery at the output end of the power terminal, the battery is directly electrically connected to the electrolyzer, and the battery is electrically connected to the auxiliary system through the second DC transformer module. On the one hand, the battery stores the electric energy of the photovoltaic power supply and the wind power supply, and can output a stable voltage and current as long as the battery has power, thereby avoiding the problem of frequent fluctuations in the output voltage of the photovoltaic power supply and the wind power supply, and reducing the problem of unstable power of the electrolyzer. On the other hand, the high voltage output by the battery is adjusted to a low voltage output through the second DC transformer module, and the alkali liquid pump, pneumatic valve and other components in the auxiliary system are directly powered to ensure that the low-voltage accessories of the alkaline water electrolysis hydrogen production system can be used. The advantage of this design is that it can ensure that the alkaline water electrolysis hydrogen production system can be operated all the time, and the effect of decoupling the wind and solar power from the electrolyzer power is achieved through the battery.

[0039] In some optional embodiments, the battery includes a plurality of battery cells, and some or all of the battery cells in the battery are connected in parallel so that the output voltage of the battery is no greater than 500V.

[0040] Specifically, when the battery supplies power to the electrolyzer, the power, current and voltage range of the battery must meet the power characteristics of water electrolysis and hydrogen production, that is, low voltage and high current, for example, the current of a 5MW electrolyzer is about 10,000A, and the voltage is about 500V. This feature is different from the power characteristics of traditional batteries, which are high voltage and low current, such as 10kV cables. Therefore, the embodiment of the present invention redesigns the battery. Considering that the battery is often composed of multiple cells, the embodiment of the present invention sets some or all of the cells in the battery in parallel according to the voltage requirements of the electrolyzer. The parallel connection can increase the current output of the overall battery circuit and reduce the voltage, so that the output voltage of the battery is not greater than 500V, thereby realizing the battery characteristics of low voltage and high current, increasing the matching degree between the battery and the electrolyzer, and improving the reliability of the water electrolysis experiment.

[0041] In some optional embodiments, Figure 3 As shown, the power module also includes a first switch; the power terminal is also electrically connected to the electrolytic cell, and the first switch is arranged between the power terminal and the line of the electrolytic cell; the control subsystem is also signal-connected to the first switch, the battery and the power terminal.

[0042] Specifically, an embodiment of the present invention provides another connection method of the battery. The first connection method is that the battery of the aforementioned embodiment is directly connected to the electrolytic cell. The second connection method adds a circuit in which the power terminal is directly electrically connected to the electrolytic cell, and then a first switch is set between the power terminal and the circuit of the electrolytic cell, wherein the first switch is controlled by the control subsystem. When the first switch is disconnected, the power terminal, the battery and the electrolytic cell are connected in series; when the first switch is closed, the power terminal, the battery and the electrolytic cell are connected in parallel.

[0043] For the series connection method, the electricity from the photovoltaic power source and the wind power source enters the battery, and the battery provides stable power for the electrolyzer. For the parallel connection method, most of the electricity from the photovoltaic power source and the wind power source provides power for the electrolyzer, and a small part of the electricity charges the battery. When the power of the photovoltaic power source and the wind power source fluctuates and causes insufficient power for the electrolyzer, the battery will discharge the electricity.

[0044] The above-mentioned series and parallel connection methods are applied to two control situations respectively. If the output power of the power terminal is greater than the rated power of the battery, the parallel mode is adopted. If the output power of the power terminal is lower than the rated power of the battery, the series mode is adopted. In the parallel mode, the output power of the power terminal can meet the power demand of the electrolyzer. The main purpose of the battery is to eliminate the high-frequency energy in the circuit and the power below the rated power threshold (for example, 5%) that the alkaline liquid hydrogen production system cannot absorb. In the series mode, the output power of the power terminal cannot meet the power demand of the electrolyzer, and the battery energy storage is used to ensure the stability of the power output to the electrolyzer.

[0045] According to an embodiment of the present invention, an embodiment of a control method for an alkaline hydrogen production system is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0046] In this embodiment, a control method for an alkaline hydrogen production system is provided, which can be used for a control subsystem in the alkaline hydrogen production system. Figure 4 is a flow chart of a control method for an alkaline hydrogen production system according to an embodiment of the present invention. Figure 4 As shown, the process includes the following steps:

[0047] Step S401, starting the power module to power on the electrolytic cell;

[0048] Step S402, start the gas-liquid separation subsystem to separate the hydrogen generated by the electrolyzer.

[0049] Step S403, shutting down when it is detected that the power output by the power module to the electrolyzer is lower than the preset lower limit of the rated power of the electrolyzer. The preset lower limit is a percentage of the rated power of the electrolyzer calculated by the organic-inorganic composite diaphragm in the electrolyzer, which can make the hydrogen in oxygen index exceed the hydrogen in oxygen threshold.

[0050] Specifically, the power module is started to start the work of electrolyzing water in the electrolyzer, because an organic-inorganic composite diaphragm is set in the electrolyzer, and its pore size is only 100nm, which can block hydrogen from penetrating horizontally to the anode side. The pore size and porosity of the composite membrane determine its ability to block gas penetration. The smaller the pore size, the better the gas blocking ability, thereby blocking the hydrogen index in oxygen from exceeding the hydrogen threshold in oxygen, and then determining that the wind and solar power can break through the 20% limit of the rated power of the electrolyzer, and electrolyzing water with lower wind and solar power will not cause the hydrogen index in oxygen to exceed the threshold. For example, when the hydrogen index in oxygen exceeds the hydrogen threshold in oxygen, due to the good blocking ability of the organic-inorganic composite diaphragm, the output power of the power module is calculated to be reduced to 5% of the rated power of the electrolyzer, so that 5% of the rated power of the electrolyzer can be used as the preset lower limit of the rated power of the electrolyzer. The system will only shut down when the power output by the power module to the electrolyzer is lower than 5% of the rated power of the electrolyzer, otherwise it will not shut down. This is because the hydrogen-in-oxygen index will not exceed the hydrogen-in-oxygen threshold when it is above 5% of the rated power, which will not cause the electrolyzer to shut down, allowing the electrolyzer to meet any fluctuations in wind and solar power, thereby significantly improving the life of the electrolyzer.

[0051] In some optional implementation manners, the above step S401 includes:

[0052] Step a1, collecting the output power of the power terminal;

[0053] Step a2, comparing the output power with the rated power of the battery;

[0054] Step a3, when the output power is greater than the rated power, closing the first switch;

[0055] Step a4: when the output power is less than or equal to the rated power, turn off the first switch.

[0056] Specifically, the embodiment of the present invention collects the output power of the power terminal in real time through the control subsystem, and compares the output power of the power terminal with the rated power of the battery to determine whether the output power of the power terminal is greater than the rated power of the battery. If the output power of the power terminal is greater than the rated power of the battery, it means that the output power of the power terminal can meet the power demand of the electrolyzer, so the first switch is closed, and the power supply circuit of the alkaline hydrogen production system is controlled to be a parallel connection method. The power terminal mainly supplies power to the electrolyzer, and the excess electric energy is charged into the battery for storage. If the output power of the power terminal is less than or equal to the rated power of the battery, the first switch is disconnected, and the series connection method is adopted. The output power of the power terminal cannot meet the power demand of the electrolyzer, and the power output to the electrolyzer is ensured to be stable through battery energy storage.

[0057] In some optional implementations, an alkaline hydrogen production system control method provided by an embodiment of the present invention further includes:

[0058] Step b1, when the first switch is closed, determining whether the output power is greater than a first preset power threshold;

[0059] Step b2, when the output power is greater than the first preset power threshold, increasing the proportion of power output from the power terminal to the battery;

[0060] Step b3, determining whether the output power is less than a second preset power threshold;

[0061] Step b4, when the output power is less than the second preset power threshold, reduce the proportion of power output from the power terminal to the battery, and increase the power output from the battery to the electrolytic cell, and the second preset power threshold is less than the first preset power threshold.

[0062] Specifically, when the parallel connection method is adopted, the battery has the effect of shaving peaks and filling valleys of the output power of the battery terminal. First, two power thresholds are set, namely a first preset power threshold and a second preset power threshold, and the first preset power threshold is greater than the second preset power threshold. In the embodiment of the present invention, the first preset power threshold is used to represent the scenario where the output power of the battery terminal is too large, and the second preset power threshold is used to represent the scenario where the output power of the battery terminal is too small.

[0063] When the battery terminal output power is greater than the first preset power threshold, it indicates that the wind and solar output power is too large, which may easily damage the electrolysis equipment, so the power supply terminal is controlled to output more electricity to the battery for storage, and the electricity output to the electrolyzer is reduced to protect the electrolyzer equipment. When the battery terminal output power is less than the second preset power threshold, it indicates that the wind and solar output power is too small to meet the normal operation of the electrolyzer, so the proportion of electricity output from the power supply terminal to the battery is reduced, and the electricity output from the battery to the electrolyzer is released, and the battery is used to supplement the power of the electrolyzer to ensure stable operation of the electrolyzer. The control method provided by the embodiment of the present invention further improves the stability of alkaline hydrogen production.

[0064] In some optional implementations, the alkaline hydrogen production system control method provided in the embodiment of the present invention further includes:

[0065] Step c1, detecting the quality of the electrolyte in the electrolytic cell;

[0066] Step c2, when the quality of the electrolyte is lower than a preset quality threshold, the water and alkali replenishment subsystem is started to add electrolyte to the electrolytic cell.

[0067] Specifically, in an embodiment of the present invention, the control subsystem also monitors the quality of the electrolyte in the electrolyzer in real time to ensure that there is sufficient electrolyte. When the quality of the electrolyte is lower than a preset quality threshold, it indicates that the electrolyzer needs to be replenished, thereby controlling the water-alkali replenishment subsystem to add electrolyte to the electrolyzer, further improving the reliability of hydrogen production by electrolysis.

[0068] The technical solution provided by the present invention has the following advantages:

[0069] 1) By using an organic-inorganic composite diaphragm in an alkaline electrolytic cell, the lower operating limit of the alkaline electrolytic cell can be reduced from 20% of the rated power to 5%.

[0070] 2) Add new power terminals to take into account both wind power and photovoltaic power input.

[0071] 3) Batteries are set up and connected in series to improve the current situation where the lower limit of the load range of the alkaline water electrolysis hydrogen production system is only 5% from the perspective of wind-solar coupled hydrogen production system control, so as to achieve 100% energy utilization of renewable energy coupled hydrogen production and improve power supply stability.

[0072] 4) Batteries are set up. Under the condition of parallel connection, when the photovoltaic and wind power are lower than 5% of the rated power of the alkaline water electrolysis hydrogen production system, the batteries are responsible for supplementing to ensure that the alkaline water electrolysis hydrogen production system operates at 5% of the rated power.

[0073] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0074] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0075] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. An alkaline hydrogen production system, characterized in that: include: Power modules, electrolyzers and auxiliary systems; The power supply module is electrically connected to the electrolytic cell and the auxiliary system respectively; The auxiliary system includes a control subsystem, a gas-liquid separation subsystem, and a water-alkali supplement subsystem; The water-alkali supplement subsystem is connected to the electrolytic cell pipeline, the gas-liquid separation subsystem is connected to the electrolytic cell pipeline, and the control subsystem is respectively connected to the gas-liquid separation subsystem, the water-alkali supplement subsystem and the electrolytic cell signal; The diaphragm in the electrolytic cell is an organic-inorganic composite diaphragm.

2. The alkaline hydrogen production system according to claim 1, characterized in that: The power supply module includes: a photovoltaic power supply, a wind power supply, a first DC transformer module, a rectifier module, a power supply terminal, a second DC transformer module and a battery; The photovoltaic power source is electrically connected to the first DC transformer module; The wind power supply is electrically connected to the rectifier module; The first DC transformer module and the rectifier module are both electrically connected to the power terminal; The power terminal is electrically connected to the battery; The battery is electrically connected to the electrolytic cell; The battery is also electrically connected to the second DC transformer module; The second DC transformer module is electrically connected to the auxiliary system.

3. The alkaline hydrogen production system according to claim 2, characterized in that: The power module also includes a first switch; The power terminal is also electrically connected to the electrolytic cell, and the first switch is arranged between the power terminal and the circuit of the electrolytic cell; The control subsystem is also signally connected to the first switch, the battery, and the power terminal.

4. The alkaline hydrogen production system according to claim 2 or 3, characterized in that: The battery includes a plurality of cells, and some or all of the cells in the battery are connected in parallel so that the output voltage of the battery is no greater than 500V.

5. A control method for an alkaline hydrogen production system, characterized in that: Applied to control subsystems, including: Start the power module to power on the electrolytic cell; Starting a gas-liquid separation subsystem to separate hydrogen generated by the electrolyzer; The electrolyzer is shut down when it is detected that the power output by the power module to the electrolyzer is lower than the preset lower limit of the rated power of the electrolyzer. The preset lower limit is a percentage of the rated power of the electrolyzer calculated by the organic-inorganic composite diaphragm in the electrolyzer, which can make the hydrogen in oxygen index exceed the hydrogen in oxygen threshold.

6. The method according to claim 5, characterized in that The starting power supply module powers on the electrolytic cell, comprising: Collect the output power of the power terminal; comparing the output power with the rated power of the battery; When the output power is greater than the rated power, closing the first switch; When the output power is less than or equal to the rated power, the first switch is turned off.

7. The method according to claim 6, characterized in that The method further comprises: When the first switch is closed, determining whether the output power is greater than a first preset power threshold; When the output power is greater than a first preset power threshold, increasing the proportion of power output from the power terminal to the battery; Determining whether the output power is less than a second preset power threshold; When the output power is less than a second preset power threshold, the proportion of power output from the power terminal to the battery is reduced, and the power output from the battery to the electrolytic cell is increased, and the second preset power threshold is less than the first preset power threshold.

8. The method according to claim 5, characterized in that The method further comprises: Detect the quality of electrolyte in the electrolytic cell; When the quality of the electrolyte is lower than a preset quality threshold, the water and alkali supplement subsystem is started to add electrolyte to the electrolytic cell.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method according to any one of claims 5 to 8.

10. A computer program product, characterized in that The method comprises computer instructions for causing a computer to execute the method according to any one of claims 5 to 8.

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