Separator liquid level control method and system in water electrolysis hydrogen production process

Abstract

The invention discloses a method and system for controlling the liquid level of a separator in the water electrolysis hydrogen production process, and belongs to the technical field of electrolytic bath control. According to the method, the liquid level of a separator serves as a main variable, the water supplementing flow serves as an auxiliary variable, a cascade control system is formed, meanwhile, change values of the pressure of an electrolysis system, the power of an electrolytic bath and the temperature of alkali liquor serve as feed-forward signals and are input into a feed-forward controller, and the output values are summed and then jointly form a feed-forward-cascade control system with the cascade control system. According to the control method, the hydrogen side liquid level and the oxygen side liquid level can be accurately controlled, and the problem that the difference between the hydrogen side liquid level and the oxygen side liquid level is too large due to changes of system pressure, electrolytic cell power, alkali liquor temperature and water supplementing flow is solved; and the problems of equipment damage and even casualties caused by explosion risks due to mixing of gas on the two sides when the liquid level is too low can also be avoided, and economic losses caused by protection shutdown triggered by liquid level high-low alarm can also be avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrolyzer control, and in particular relates to a separator liquid level control method and system in a process of electrolyzing water to produce hydrogen. Background Art

[0002] In the process of producing hydrogen by alkaline water electrolysis, it is usually necessary to control the liquid levels in the hydrogen side separator and the oxygen side separator, and ensure that the liquid level difference in the hydrogen side separator and the liquid level in the oxygen side separator is within a certain range to ensure the normal operation of the electrolysis process.

[0003] Existing liquid level control methods involve manually operating the equipment to maintain the oxygen-side liquid level within a certain range before formal operation. During operation, the oxygen-side liquid level is controlled empirically, with the water replenishment frequency set in the DCS / PLC controller. This water is then replenished alternately to the hydrogen and oxygen separators to maintain the oxygen-side liquid level. Alternatively, a DCS / PLC controller is used, employing a PID control algorithm. The oxygen-side liquid level is used as the setpoint, and the hydrogen-side liquid level is used as the actual value (feedback value). The PID output signal controls the liquid level control valve, ensuring that the hydrogen-side liquid level tracks the oxygen-side liquid level. This prevents the mixing of gases on both sides from causing explosions when the liquid level is too low, or triggering a protective shutdown that could impact production.

[0004] However, the control accuracy of the above control method is not accurate because the factors affecting the liquid level include alkali solution temperature, electrolytic cell power, system pressure, and water replenishment rate. Both alkali solution temperature and electrolytic cell power affect system pressure, which in turn affects the oxygen-side liquid level. However, since the system pressure does not immediately reflect changes in alkali solution temperature and power, changes in alkali solution temperature and power are not immediately reflected in the system pressure. Therefore, directly controlling the liquid level using pressure is not effective. Relying solely on PID control of the liquid level cannot overcome "false water levels" caused by pressure changes, which can lead to controller malfunctions. The control effect is also not timely (feedback control only takes effect after the disturbance has taken effect, and the system has both capacity hysteresis and pure hysteresis). Furthermore, it cannot overcome the disturbance caused by changes in the water replenishment flow rate. If the liquid level is used as the controlled variable and the changes in system pressure, electrolytic cell power, and alkali solution temperature (disturbance) are used as feedforward signals, the disturbance caused by changes in the water replenishment flow rate cannot be overcome. If a cascade control system is constructed with liquid level as the primary variable and water replenishment flow rate as the secondary variable, it cannot overcome disturbances caused by system pressure, electrolytic cell power, and alkali solution temperature. From the above, it can be seen that the existing liquid level control methods are unable to achieve precise control of the liquid level. Summary of the Invention

[0005] In view of the above problems, in a first aspect, the present invention proposes a method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water, the control method comprising the following steps:

[0006] Obtain real-time data of electrolysis system pressure, electrolysis cell power, alkali solution temperature, separator liquid level and separator set liquid level respectively;

[0007] Using the change in pressure of the electrolysis system, the change in power of the electrolytic cell, and the change in temperature of the alkali solution as inputs of corresponding feedforward controllers, and determining a first result according to output results of the corresponding feedforward controllers;

[0008] The real-time data of the separator liquid level and the separator set liquid level are used as inputs of the main controller, and a second result is outputted;

[0009] The first result and the second result are added together as the setting value of the sub-controller, the separator water supply flow rate is used as the feedback value of the sub-controller, the setting value of the sub-controller and the feedback value of the sub-controller are used together as the input of the sub-controller, and the water supply flow rate is controlled according to the output signal of the sub-controller, thereby controlling the separator liquid level.

[0010] Furthermore, when controlling the liquid level of the oxygen side separator, the electrolysis system pressure is the oxygen side pressure of the oxygen side separator, the separator liquid level is the actual liquid level of the oxygen side separator, and the separator set liquid level is the oxygen side separator set liquid level;

[0011] When controlling the hydrogen side separator liquid level, the electrolysis system pressure is the hydrogen side pressure of the hydrogen side separator, the separator liquid level is the actual liquid level of the hydrogen side separator, and the separator set liquid level is the hydrogen side separator set liquid level.

[0012] Furthermore, the electrolytic cell power is calculated based on the real-time voltage and current of the power supply.

[0013] Furthermore, the alkali solution temperature is measured by the oxygen side outlet thermometer of the electrolytic cell.

[0014] Furthermore, using the change value of the electrolysis system pressure, the change value of the electrolytic cell power, and the change value of the alkali solution temperature as inputs of corresponding feedforward controllers, and determining the first result according to the output results of the corresponding feedforward controllers includes:

[0015] Inputting the difference between two adjacent real-time pressure data of the electrolysis system into the pressure feedforward controller and outputting first information;

[0016] Inputting the difference between two adjacent real-time data of electrolytic cell power into a power feedforward controller and outputting second information;

[0017] The difference between two adjacent alkali solution temperature real-time data is input into the temperature feedforward controller to output third information;

[0018] The first information, the second information and the third information are summed to obtain a first result.

[0019] Furthermore, the feedforward controller and the sub-controller adopt a P control algorithm, and the main controller adopts a PID control algorithm.

[0020] In a second aspect, the present invention proposes a control system for a separator liquid level in a process of producing hydrogen by electrolysis of water, comprising:

[0021] An acquisition unit, used to respectively acquire real-time data of electrolysis system pressure, electrolysis cell power, alkali solution temperature, separator liquid level and separator set liquid level;

[0022] a first result output unit, configured to use the change in pressure of the electrolysis system, the change in power of the electrolytic cell, and the change in temperature of the alkali solution as inputs of corresponding feedforward controllers, and determine a first result according to output results of the corresponding feedforward controllers;

[0023] a second result output unit, configured to take the real-time data of the separator liquid level and the separator set liquid level as inputs of the main controller and output a second result;

[0024] A liquid level control unit is used to add the first result and the second result as the set value of the sub-controller, and the separator water supply flow rate as the feedback value of the sub-controller. The set value of the sub-controller and the feedback value of the sub-controller are used as the input of the sub-controller, and the water supply flow rate is controlled according to the output signal of the sub-controller, thereby controlling the separator liquid level.

[0025] In a third aspect, the present invention proposes an electrolyzer hydrogen production system comprising a control system for the separator liquid level in the process of hydrogen production by electrolysis of water.

[0026] In a fourth aspect, the present invention provides an electronic device comprising a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus;

[0027] a memory storing a computer program;

[0028] The processor is used to implement the method for controlling the liquid level of the separator in the process of producing hydrogen by electrolysis of water when executing the program stored in the memory.

[0029] In a fifth aspect, the present invention proposes a computer-readable storage medium storing a computer program. When the computer program is run, it executes the method for controlling the liquid level of the separator in the process of producing hydrogen by electrolysis of water.

[0030] Beneficial effects of the present invention:

[0031] The present invention uses the separator liquid level as the main variable and the water supply flow rate as the secondary variable to form a cascade control system. At the same time, the change values ​​of the electrolysis system pressure, electrolytic cell power, and alkali solution temperature are used as feedforward signals, which are respectively input into the feedforward controller. The output values ​​are summed and then combined with the cascade control system to form a feedforward-cascade control system. The above control method can accurately control the hydrogen side liquid level and the oxygen side liquid level, avoiding the problem of excessive difference in the hydrogen side and oxygen side liquid levels due to changes in system pressure, electrolytic cell power, alkali solution temperature and water supply flow rate. It can also avoid the problem of explosion risk caused by mixing of gases on both sides when the liquid level is too low, resulting in damage to equipment and even casualties. It can also avoid the economic losses caused by the high and low liquid level alarm triggering a protective shutdown.

[0032] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 A flow chart of an alkaline water electrolysis process is shown;

[0035] Figure 2 A flow chart showing a method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water, as proposed in an embodiment of the present invention;

[0036] Figure 3 Shows the oxygen side feedforward-cascade control block diagram in an embodiment of the present invention;

[0037] Figure 4 Shows a hydrogen side feedforward-cascade control block diagram in an embodiment of the present invention;

[0038] Figure 5 A schematic diagram of an electronic device according to an embodiment of the present invention is shown;

[0039] Description of the drawings: 1. Power supply; 2. Voltmeter; 3. Ammeter; 4. Electrolyzer; 5. Temperature transmitter; 6. Hydrogen side separator; 7. Hydrogen side liquid level transmitter; 8. First flow meter; 9. Liquid level regulating valve; 10. Hydrogen side water supply valve; 11. Oxygen side separator; 12. Oxygen side liquid level transmitter; 13. Second flow meter; 14. Pressure transmitter; 15. Pressure regulating valve; 16. Oxygen side water supply valve; 17. Water supply pump. DETAILED DESCRIPTION

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only 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 ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0041] The process flow chart of hydrogen production by electrolysis of water is as follows Figure 1 As shown, the electrolytic cell 4 is powered by a power source 1 and has an alkali inlet. The alkali is electrolyzed in the electrolytic cell 4 to generate hydrogen and oxygen. The generated hydrogen and oxygen (mixed with the alkali) enter the hydrogen-side separator 6 and the oxygen-side separator 11, respectively, for gas-liquid separation. The separated alkali returns to the electrolytic cell 4 to participate in the next electrolysis cycle. The separated hydrogen and oxygen enter the purification system (not shown). If water is not replenished during electrolysis, desalted water (makeup water) is replenished to the hydrogen-side separator 6 and the oxygen-side separator 11, respectively, via a water replenishment pump, a hydrogen-side water replenishment valve 10, and an oxygen-side water replenishment valve 16. It should be noted that the complete process flow is that the mixture coming out of the hydrogen side separator 6 / oxygen side separator 11 passes through the hydrogen heat exchanger / oxygen heat exchanger, hydrogen scrubber / oxygen scrubber, hydrogen side gas-water separator / oxygen side gas-water separator and then enters the purification system. The alkali solution refluxes through the heat exchanger and alkali solution circulation pump before entering the electrolyzer 4. The desalted water enters the hydrogen side gas-liquid separator / oxygen side gas-liquid separator and then flows back to the hydrogen side separator 6 / oxygen side separator 11. Figure 1 The above process is not fully shown in FIG.

[0042] Based on the above-mentioned process flow for producing hydrogen by electrolysis of water, the present invention proposes a control system for the liquid level of a separator in the process of producing hydrogen by electrolysis of water, comprising:

[0043] An acquisition unit, used to respectively acquire real-time data of electrolysis system pressure, electrolysis cell power, alkali solution temperature, separator liquid level and separator set liquid level;

[0044] a first result output unit, configured to use the change in pressure of the electrolysis system, the change in power of the electrolytic cell, and the change in temperature of the alkali solution as inputs of corresponding feedforward controllers, and determine a first result according to output results of the corresponding feedforward controllers;

[0045] a second result output unit, configured to take the real-time data of the separator liquid level and the separator set liquid level as inputs of the main controller and output a second result;

[0046] A liquid level control unit is used to add the first result and the second result as the set value of the sub-controller, and the separator water supply flow rate as the feedback value of the sub-controller. The set value of the sub-controller and the feedback value of the sub-controller are used as the input of the sub-controller, and the water supply flow rate is controlled according to the output signal of the sub-controller, thereby controlling the separator liquid level.

[0047] In an exemplary embodiment of the present invention, the acquisition unit includes a pressure transmitter 14 for collecting electrolysis system pressure, an ammeter 3 for collecting power supply 1 current, a voltmeter 2 for collecting power supply 1 voltage, an oxygen-side temperature transmitter 5 for collecting alkali solution temperature, and an oxygen-side level transmitter 12 or a hydrogen-side level transmitter 7 for collecting separator liquid level. The first result output unit is a feedforward controller, the second result output unit is a main controller, and the level control unit is a sub-controller.

[0048] In another exemplary embodiment of the present invention, a water electrolysis hydrogen production system is proposed, which includes the control system of the separator liquid level in the water electrolysis hydrogen production process mentioned in the above embodiment, and some structures can be as follows: Figure 1 The hydrogen side separator 6 is provided with a hydrogen mixing inlet, a hydrogen outlet, a hydrogen side water replenishment port, a hydrogen side alkali liquid outlet and a hydrogen side liquid level transmitter 7. The oxygen mixing inlet is connected to the hydrogen outlet pipeline of the electrolyzer 4, and is used to transport the hydrogen mixed with the alkali liquid in the electrolyzer 4 to the hydrogen side separator 6 for separation; the hydrogen outlet is connected to the hydrogen outlet pipeline, and a liquid level regulating valve 9 is installed on the hydrogen outlet pipeline for regulating the liquid level in the hydrogen side separator 6; the hydrogen side water replenishment port is connected to the hydrogen side water replenishment pipeline, and a first flowmeter 8 and a hydrogen side water replenishment valve 10 are installed on the hydrogen side water replenishment pipeline. The first flowmeter 8 collects the water replenishment flow of the hydrogen side separator 6; the alkali liquid outlet is connected to the alkali liquid inlet pipeline of the electrolyzer 4, and is used to return the alkali liquid separated in the hydrogen side separator 6 to the electrolyzer 4; the hydrogen side liquid level transmitter 7 is used to collect the liquid level in the hydrogen side separator 6.

[0049] The oxygen side separator 11 is provided with an oxygen mixing inlet, an oxygen outlet, an oxygen side water replenishment inlet, an oxygen side alkali solution outlet and an oxygen side liquid level transmitter 12 . The oxygen mixed inlet is connected to the oxygen outlet pipeline of the electrolyzer 4, and is used to transport the oxygen mixed with the alkali solution in the electrolyzer 4 to the oxygen side separator 11 for separation. A temperature transmitter 5 is provided on the oxygen outlet pipeline of the electrolyzer 4 for detecting the temperature of the alkali solution; the oxygen outlet is connected to the oxygen outlet pipeline, and a pressure transmitter 14 and a pressure regulating valve 15 are installed on the oxygen outlet pipeline for collecting the system pressure and adjusting it; the oxygen side water supply port is connected to the oxygen side water supply pipeline, and a second flowmeter 13 and an oxygen side water supply valve 16 are provided on the oxygen side water supply pipeline, and the second flowmeter 13 collects the water supply flow of the oxygen side separator 11; the oxygen side alkali solution outlet is connected to the alkali solution inlet pipeline of the electrolyzer 4, and is used to return the alkali solution separated in the oxygen side separator 11 to the electrolyzer 4; the oxygen side liquid level transmitter 12 is used to collect the liquid level in the oxygen side separator 11.

[0050] The hydrogen side water supply valve 10 and the oxygen side water supply valve 16 are connected to a water supply pump, and the water supply pump pumps desalted water into the hydrogen side water supply pipeline and / or the oxygen side water supply pipeline.

[0051] It should be noted that the present invention does not impose any specific restrictions on the type of power source 1, including wind power, photovoltaic power generation or grid power. The power source 1 is equipped with a voltmeter 2 and an ammeter 3 to determine the power change of the electrolyzer; the feedforward controller, the main controller and the sub-controller are Figure 1 Not shown.

[0052] In view of the above electrolysis process, the present invention proposes a liquid level control method for hydrogen production by electrolysis of water, such as Figure 2 As shown, the control method includes the following steps:

[0053] S1: Obtain real-time data of electrolysis system pressure, electrolysis cell power, alkali solution temperature, separator liquid level, and separator set liquid level respectively;

[0054] S2: using the change in pressure of the electrolysis system, the change in power of the electrolytic cell, and the change in temperature of the alkali solution as inputs of corresponding feedforward controllers, and determining a first result according to outputs of the corresponding feedforward controllers;

[0055] S3: using the real-time data of the separator liquid level and the separator set liquid level as inputs of the main controller and outputting a second result;

[0056] S4: The first result and the second result are added together as the setting value of the sub-controller, the separator water supply flow rate is used as the feedback value of the sub-controller, the setting value of the sub-controller and the feedback value of the sub-controller are used as the input of the sub-controller, and the water supply flow rate is controlled according to the output signal of the sub-controller, thereby controlling the separator liquid level.

[0057] It should be noted that the above method can control both the oxygen-side separator liquid level and the hydrogen-side separator liquid level. When controlling the oxygen-side separator liquid level, the electrolysis system pressure in step S1 is the oxygen-side pressure of oxygen-side separator 11, and the separator liquid level is the actual liquid level of oxygen-side separator 11; when controlling the hydrogen-side separator liquid level, the electrolysis system pressure is the hydrogen-side pressure of hydrogen-side separator 6, and the separator liquid level is the actual liquid level of hydrogen-side separator 6. The alkali liquid temperature, whether controlling the oxygen-side separator liquid level or the hydrogen-side separator liquid level, is measured based on the temperature measured by temperature transmitter 5 installed on the oxygen outlet pipeline of electrolyzer 4; the electrolyzer power is calculated based on the real-time voltage and current of power supply 1. The set liquid levels of the oxygen-side separator and the hydrogen-side separator can be set in the DCS / PLC controller of the electrolysis system.

[0058] In step S2, the change value of the electrolysis system pressure, the change value of the electrolytic cell power, and the change value of the alkali solution temperature are respectively used as inputs of corresponding feedforward controllers, and determining the first result according to the output results of the corresponding feedforward controllers includes the following steps:

[0059] Inputting the difference between two adjacent real-time pressure data of the electrolysis system into the pressure feedforward controller and outputting first information;

[0060] Inputting the difference between two adjacent real-time data of electrolytic cell power into a power feedforward controller and outputting second information;

[0061] The difference between two adjacent alkali solution temperature real-time data is input into the temperature feedforward controller to output third information;

[0062] The first information, the second information and the third information are summed to obtain a first result.

[0063] The following combination Figure 3The control block diagram shown in the figure illustrates a method for controlling the oxygen-side separator liquid level during the hydrogen production process by water electrolysis. In this control process, the oxygen-side separator liquid level L serves as the primary variable, and the oxygen-side separator 11 water supply flow rate F serves as the secondary variable, forming a cascade control system. The oxygen-side separator liquid level and the oxygen-side separator set level x1 serve as inputs to the main controller, whose output is x2. Simultaneously, the changes in the electrolysis system pressure, electrolyzer power, and alkali solution temperature (disturbance) are fed into the feedforward controller as feedforward signals. The sum of these outputs yields x3, which, together with the cascade control system, forms an oxygen-side feedforward-cascade control system. The main controller's output x2 and the feedforward controller's output x3 are added together to form the setpoint for the secondary controller, with the water supply flow rate F serving as the secondary controller's feedback value. The sub-controller's setpoint and feedback values ​​serve as its inputs. The secondary controller's output signal y1 acts on the oxygen-side water supply valve 16 to control the water supply flow rate, thereby achieving liquid level control of the oxygen-side separator.

[0064] During the above process, the main controller uses a PID control algorithm to precisely control the oxygen-side separator liquid level, stabilizing the oxygen-side separator liquid level above the oxygen-side separator set liquid level x1. The oxygen-side separator set liquid level x1 can be set in the DCS / PLC controller. The liquid level is acquired by the oxygen-side liquid level transmitter 12. By integrating the three control functions of proportional (P), integral (I), and differential (D), the proportional part outputs the result x2 based on the error signal between the oxygen-side separator set liquid level x1 and the oxygen-side separator liquid level to reduce the error. The integral part integrates the error signal to eliminate steady-state error, allowing the oxygen-side separator liquid level to stabilize at the oxygen-side separator set liquid level x1. The differential part differentiates the error signal to predict the error change trend and adjust the output result x2 in advance, thereby adjusting the oxygen-side separator liquid level and ensuring high control quality of the system.

[0065] The sub-controller adopts the P control algorithm to quickly overcome the influence of the fluctuation of the water supply flow rate. The output result x2 of the main controller is added to the output result x3 of the feedforward controller as the set value of the sub-controller, and the oxygen side separator water supply flow rate F is used as the feedback value of the sub-controller. The set value of the sub-controller and the feedback value of the sub-controller are used as the input of the sub-controller. The output y1 of the sub-controller acts on the oxygen side water supply valve 16 to control the oxygen side separator water supply flow rate. The existence of the feedback value of the sub-controller reduces the accuracy requirements of the feedforward control model, improves the anti-disturbance ability of the system, and has a certain adaptive ability.

[0066] The feedforward controller generally adopts static feedforward, for example, a P controller is used as the feedforward controller, and parameter setting is completed during the actual debugging process. Changes in system pressure, electrolytic cell power, and alkali solution temperature can be discovered in advance, thereby improving the control quality. In one embodiment of the present invention, the feedforward controller includes a pressure feedforward controller, a power feedforward controller, and a temperature feedforward controller. The output values ​​of the pressure feedforward controller, the power feedforward controller, and the temperature feedforward controller are summed to obtain x3. In other embodiments of the present invention, the feedforward controller can also adopt dynamic feedforward. The specific model needs to be determined according to the actual situation on site (dynamic characteristics of the process interference channel and the control channel), but its structure is often more complicated and heavily dependent on the accuracy of the model parameters. It requires a special controller or even a computer to implement, which increases the cost of the electrolysis system.

[0067] To control the hydrogen side liquid level in the electrolysis water hydrogen production process, a PID control algorithm with the oxygen side separator liquid level as the set value and the hydrogen side separator liquid level as the actual value can be used; or a cascade control algorithm with the hydrogen side separator liquid level as the main variable and the hydrogen side water supply flow rate as the secondary variable can be used. In an exemplary embodiment of the present invention, the same feedforward-cascade control method as the oxygen side liquid level control is used, and the electrolysis system pressure is replaced with the hydrogen side pressure of the hydrogen side separator 6. In this control process, the hydrogen side separator liquid level L is used as the main variable, and the hydrogen side separator 6 water supply flow rate F is used as the secondary variable, forming a hydrogen side feedforward-cascade control (such as Figure 4 As shown). The hydrogen side separator liquid level and the hydrogen side separator 6 set liquid level x1 are used as inputs of the main controller, and the output result of the main controller is x2. At the same time, the change values ​​of the electrolysis system pressure (hydrogen-oxygen side pressure of the hydrogen side separator 6), the electrolytic cell power, and the alkali solution temperature are respectively input into the feedforward controller as feedforward signals, and the respective output results are summed to obtain x3, which is then combined with the cascade control system to form a feedforward-cascade control system. The output result x2 of the main controller and the output result x3 of the feedforward controller are added together as the set value of the sub-controller, and the water supply flow rate F is used as the feedback value of the sub-controller. The set value of the sub-controller and the feedback value of the sub-controller are used together as the input of the sub-controller. According to the output signal y1 of the sub-controller, the hydrogen side water supply valve 10 is acted on to control the water supply flow rate, thereby realizing the liquid level control of the hydrogen side separator.

[0068] The above control process is a periodic dynamic cycle process. In an exemplary embodiment of the present invention, the main controller, the sub-controller and the feedforward controller have a default operating cycle of 500ms, and each cycle is executed starting from S1.

[0069] Another exemplary embodiment of the present invention provides an electronic device. Figure 5As shown, the electronic device includes at least one processor 501, at least one communication interface 502, at least one memory 503 and at least one communication bus 504; wherein the processor 501, the communication interface 502 and the memory 503 communicate with each other via the communication bus 504;

[0070] Memory 503, storing computer programs;

[0071] The processor 501 is configured to implement the method for controlling the liquid level of the separator in the process of producing hydrogen by electrolysis of water when executing the program stored in the memory 503 .

[0072] Optionally, the communication interface may be an interface of a communication module, such as an interface of a GSM module; the processor may be a CPU, or an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention. The memory may include a high-speed RAM memory, and may also include a non-volatile memory, such as at least one disk storage. The memory stores a program, and the processor calls the program stored in the memory to execute some or all of the above-mentioned method embodiments.

[0073] Based on the same inventive concept, an embodiment of the present application further provides a computer-readable storage medium storing a computer program, wherein when the computer program is executed, some or all of the above-mentioned method embodiments are implemented. Optionally, the storage medium may be a non-transitory computer-readable storage medium, for example, a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0074] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water, characterized in that: The control method comprises the following steps: respectively obtain the real-time data of electrolysis system pressure, electrolysis cell power, alkali solution temperature, separator liquid level and separator set liquid level; Using the change value of the electrolysis system pressure, the change value of the electrolytic cell power, and the change value of the alkali solution temperature as inputs of corresponding feedforward controllers, and determining a first result according to the output results of the corresponding feedforward controllers; The real-time data of the separator liquid level and the separator set liquid level are used as inputs of the main controller, and a second result is output; The first result and the second result are added together as the setting value of the sub-controller, the separator water replenishment flow rate is used as the feedback value of the sub-controller, the setting value of the sub-controller and the feedback value of the sub-controller are used together as the input of the sub-controller, and the water replenishment flow rate is controlled according to the output signal of the sub-controller, thereby controlling the separator liquid level.

2. The method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water according to claim 1, characterized in that: When controlling the liquid level of the oxygen side separator, the electrolysis system pressure is the oxygen side pressure of the oxygen side separator, the separator liquid level is the actual liquid level of the oxygen side separator, and the separator set liquid level is the oxygen side separator set liquid level; When controlling the hydrogen side separator liquid level, the electrolysis system pressure is the hydrogen side pressure of the hydrogen side separator, the separator liquid level is the actual liquid level of the hydrogen side separator, and the separator set liquid level is the hydrogen side separator set liquid level.

3. The method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water according to claim 1, characterized in that: The electrolyzer power is calculated based on the real-time voltage and current of the power supply.

4. The method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water according to claim 1, characterized in that: The alkali solution temperature is measured by the oxygen side outlet temperature of the electrolytic cell.

5. The method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water according to claim 1, characterized in that: Using the change value of the electrolysis system pressure, the change value of the electrolytic cell power, and the change value of the alkali solution temperature as the input of the corresponding feedforward controller, and determining the first result according to the output result of the corresponding feedforward controller includes: Inputting the difference between two adjacent real-time pressure data of the electrolysis system into the pressure feedforward controller, and outputting first information; Inputting the difference between two adjacent electrolytic cell power real-time data into the power feedforward controller, and outputting the second information; The difference between two adjacent alkali solution temperature real-time data is input into the temperature feedforward controller, and the third information is output; The first information, the second information and the third information are summed to obtain a first result.

6. The method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water according to any one of claims 1 to 5, characterized in that: The feedforward controller and the sub-controller adopt a P control algorithm, and the main controller adopts a PID control algorithm.

7. A control system for the liquid level of a separator in the process of producing hydrogen by electrolysis of water, characterized in that: include: An acquisition unit, used to respectively acquire real-time data of electrolysis system pressure, electrolytic cell power, alkali solution temperature, separator liquid level and separator set liquid level; A first result output unit, used to use the change value of the electrolysis system pressure, the change value of the electrolytic cell power, and the change value of the alkali solution temperature as inputs of corresponding feedforward controllers, and determine a first result according to the output results of the corresponding feedforward controllers; A second result output unit, used to use the real-time data of the separator liquid level and the separator set liquid level as inputs of the main controller and output a second result; A liquid level control unit is used to add the first result and the second result as the set value of the sub-controller, and the separator water replenishment flow rate as the feedback value of the sub-controller, and use the set value of the sub-controller and the feedback value of the sub-controller together as the input of the sub-controller, and control the water replenishment flow rate according to the output signal of the sub-controller, thereby controlling the separator liquid level.

8. An electrolyzer hydrogen production system, characterized in that: The hydrogen production system includes the control system for the separator liquid level in the process of producing hydrogen by electrolysis of water as described in claim 7.

9. An electronic device, characterized in that: It includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; a memory storing a computer program; The processor is used to implement the method for controlling the liquid level of the separator in the process of producing hydrogen by electrolysis of water as described in any one of claims 1 to 7 when executing the program stored in the memory.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed, the method for controlling the liquid level of a separator in a process of producing hydrogen by electrolysis of water as described in any one of claims 1 to 7 is executed.

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