Control method of megawatt anion exchange membrane water electrolysis hydrogen production system

Abstract

The invention provides a control method of a megawatt-level anion exchange membrane water electrolysis hydrogen production system, which comprises the following steps of: controlling a slave station to carry out inspection control on the system through a master station, and obtaining an inspection result; when the master station judges that the system meets the starting condition according to the inspection result, the system is controlled to run through the slave station, and running data of the system is displayed in real time through a human-computer interaction interface; in the inspection and system operation process, the main station judges whether abnormity exists or not in real time, if yes, the main station controls a preset indicator lamp to conduct corresponding reminding in time, and corresponding fault processing is conducted. The master station is globally monitored, the slave stations quickly respond to instructions of the master station, and data acquisition and operation control are performed on the system, so that the whole system is in an optimal operation state, and the hydrogen production efficiency is effectively improved; according to the invention, the master station judges the operation state of the system in real time, gives an alarm in time and carries out corresponding fault processing when abnormity exists, and the operation safety of the system is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of water electrolysis hydrogen production, and in particular to a control method for a megawatt-level anion exchange membrane water electrolysis hydrogen production system. Background Art

[0002] In order to achieve the goal of carbon emission reduction, vigorously developing hydrogen energy has become a global consensus. The application of hydrogen energy in energy storage, power generation, transportation, metallurgy and chemical industry is gradually expanding. If we want to realize the large-scale application of hydrogen energy, the development of water electrolysis hydrogen production systems and equipment is a crucial link.

[0003] Currently, there are four main methods of hydrogen production by water electrolysis, including alkaline water electrolysis (AWE), proton exchange membrane electrolysis (PEM), high-temperature solid oxide water electrolysis (SOE) and solid polymer anion exchange membrane electrolysis (AEM). Among them, anion exchange membrane (AEM) water electrolysis has the characteristics of low cost, high efficiency and strong controllability.

[0004] Since the megawatt-scale anion exchange membrane water electrolysis hydrogen production system is large in scale and complex in process, there is an urgent need for a control method for the megawatt-scale anion exchange membrane water electrolysis hydrogen production system that can balance safety and hydrogen production efficiency. Summary of the Invention

[0005] The present invention aims to solve the problems of poor safety and low hydrogen production efficiency in the above-mentioned prior art and provides a control method for a megawatt-level anion exchange membrane water electrolysis hydrogen production system.

[0006] Connect the preset master station to the preset human-machine interaction interface and the preset slave station respectively; Connecting the slave station to a preset system communication; Controlling the slave station through the master station to perform inspection control on the system and obtain inspection results; The master station determines whether the system meets the startup conditions according to the inspection results; If so, the slave station controls the operation of the system, including dehydrogenating the oxygen generated by the system and obtaining operation data; if not, the master station controls the preset indicator light to give a reminder and perform corresponding fault processing; Displaying the operating data of the system in real time through the human-computer interaction interface; Determining whether the operating data is normal by the slave station; If yes, the slave station determines whether a shutdown command has been received; if not, the master station controls the indicator light to give a reminder and performs corresponding fault processing; If so, the slave station performs a post-purge procedure on the system; if not, the slave station controls the system to continue operating.

[0007] Furthermore, the step of controlling the slave station to perform inspection on the system through the master station and obtaining the inspection result further includes: Powering on the system; issuing inspection instructions through the human-computer interaction interface; The master station controls the slave station according to the inspection command; The slave station collects status data of the system; The master station analyzes the status data and obtains an inspection result.

[0008] Furthermore, if yes, the operation of the system is controlled by the slave station, wherein the steps of removing hydrogen from the oxygen generated by the system and obtaining the operation data further include: issuing a start command through the human-computer interaction interface; Controlling the liquid level, temperature and concentration of the electrolyte in the preset electrolyte tank through the slave station; Controlling the electrolyte circulation between the electrolyte tank and a preset electrolytic cell through the slave station; The master station controls a preset reaction power source to supply power to the electrolytic cell; executing a preliminary purge procedure on the system through the slave station; The heat balance of the electrolyte in the electrolytic cell is controlled by the slave station.

[0009] Furthermore, the step of controlling the liquid level, temperature and concentration of the electrolyte in the electrolyte tank by the slave station further includes: Detecting real-time operating values ​​of the electrolyte in the electrolyte tank by a preset sensor, wherein the real-time operating values ​​include a real-time liquid level value, a first real-time temperature value, and a real-time concentration value; Collecting the real-time operating value through the slave station; The slave station analyzes the real-time operation value according to a preset first range value and obtains a first analysis result; The slave station controls a preset actuator according to the first analysis result, so that the real-time operation value is always within the first range.

[0010] Furthermore, the step of controlling the electrolyte circulation between the electrolyte tank and the preset electrolytic cell by the slave station further includes: Controlling a preset water pump to start at a preset frequency through the slave station; Measuring the flow rate of the electrolyte between the electrolyte tank and the electrolytic cell by a preset flow sensor and obtaining a real-time flow value; The slave station collects the real-time flow value; The slave station analyzes the real-time flow value according to a preset flow value and obtains a second analysis result; The slave station controls the actuator according to the second analysis result until the real-time flow value reaches the flow value.

[0011] Furthermore, the step of controlling a preset reaction power supply to power the electrolytic cell by the master station further includes: Outputting a preset first control voltage value through the master station and sending it to a preset reaction power supply; The reaction power supply outputs a corresponding supply voltage value and supply current value according to the first control voltage value, and is used to supply power to the electrolytic cell; Respectively detecting the supply current value, the supply voltage value, and the single-mode voltage value of the electrolytic cell through a preset current sensor, a preset first voltage sensor, and a preset second voltage sensor; The master station increases or decreases the first control voltage value according to a preset frequency and a preset amplitude, so that the supply current value and the supply voltage value reach a preset first voltage value and a preset first current value, and the single-mode voltage value is less than a preset second voltage value; Inputting a preset hydrogen production percentage through the human-computer interaction interface; The master station obtains a target current value according to the hydrogen production percentage; The master station controls the reactive power supply so that the supply current value is constantly equal to the target current value.

[0012] Furthermore, the step of executing the preliminary purge procedure on the system through the slave station further includes: Detecting the gas pressure value on the cathode side of the electrolytic cell by a preset gas pressure sensor; The slave station determines whether the gas pressure value reaches a preset first pressure value; If so, the slave station controls the actuator to purge and exhaust the mixed gas in the system; Determining, by the slave station, whether the number of times of purge and emptying is equal to a preset number; If so, the actuator is turned off.

[0013] Furthermore, the step of controlling the thermal balance of the electrolyte in the electrolytic cell by the slave station further includes: Detecting the temperature of the electrolyte at the liquid outlet of the electrolytic cell by a preset sensor and obtaining a second real-time temperature value; The slave station obtains the second real-time temperature value; The slave station analyzes the second real-time temperature value according to a preset second range value and obtains a third analysis result; The slave station controls the actuator according to the third analysis result so that the second real-time temperature value is within the preset second range value.

[0014] Furthermore, if yes, the step of performing post-purge by the slave station further includes: issuing a shutdown command through the human-computer interaction interface; Controlling the reaction power supply through the master station so that the voltage and current of the electrolytic cell are reduced to zero at a preset frequency and a preset amplitude; Detecting the gas pressure value on the cathode side of the electrolytic cell by a preset gas pressure sensor; The slave station controls the actuator to purge and drain the system at a preset frequency until the gas pressure value is less than a preset second pressure value.

[0015] Furthermore, if not, the master station controls a preset indicator light to give a reminder, and performs corresponding fault handling steps, further comprising: analyzing the fault severity level by the master station; If it is a warning, the master station controls the indicator light to give a corresponding reminder; If it is an error, the fault shutdown control is performed through the master station, wherein the fault shutdown control includes post-purge control and inspection control; If it is a fatal error, an emergency shutdown is controlled by the master station, wherein the emergency shutdown control includes post-purge control and powering off the system.

[0016] The present invention proposes global monitoring by the master station, and multiple slave stations quickly respond to the instructions of the master station, perform operation control and data collection on the system, so that the entire system is in the best operating state, and effectively improve the hydrogen production efficiency; the present invention proposes that the master station judge the operating state of the system in real time, and promptly alarm and perform corresponding fault processing when an abnormality occurs, effectively improving the safety of system operation; the present invention proposes early purging of the system, oxygen dehydrogenation and late purging, effectively reducing the residual hydrogen content in the system, further improving the safety of system operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the control method steps of a megawatt-level anion exchange membrane water electrolysis hydrogen production system in the present invention; Figure 2 This is a structural block diagram of a control method for a megawatt-class anion exchange membrane water electrolysis hydrogen production system in the present invention; Figure 3 The present invention provides a process flow chart of a control method for a megawatt-level anion exchange membrane water electrolysis hydrogen production system. DETAILED DESCRIPTION

[0018] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0020] Reference Attachment Figure 1-Figure 3 , is a control method for a megawatt-class anion exchange membrane water electrolysis hydrogen production system in one embodiment of the present invention, comprising: S1, connecting the preset master station to the preset human-machine interaction interface and the preset slave station respectively; S2 connects the slave station to the system communication; S3, the master station controls the slave station to inspect the system and obtain the inspection results; S4, the master station determines whether the system meets the startup conditions based on the inspection results; S5, if yes, then controlling the operation of the system through the slave station, including dehydrogenating the oxygen generated by the system and obtaining operation data; if no, then controlling the preset indicator light through the master station to give a reminder and perform corresponding fault processing; S6, displays the system's operating data in real time through the human-computer interaction interface; S7, judge whether the operation data is normal through the slave station; S8, if yes, the slave station determines whether a shutdown command is received; if not, the master station controls the preset indicator light to give a corresponding reminder and performs corresponding fault processing; S9, if yes, then the system is controlled to be post-purged through the slave station; if not, then the system continues to operate through the slave station.

[0021] In the above steps, the preset master station is first connected to the preset human-machine interface and the preset slave station. In a specific embodiment, a master PLC (Programmable Logic Controller) is set in the main control cabinet as the master station. The master PLC communicates with the human-machine interface (HMI) as the master station, responds to the command of the HMI, uploads data information, and transmits the working status and measurement values ​​through the Modbus of the RS-485 standard network port. The TCP / IP protocol is uploaded; then, the slave station is connected to the system communication, wherein the system is a megawatt-level anion exchange membrane water electrolysis hydrogen production system. In a specific embodiment, a control box is set as a slave station, and the megawatt-level anion exchange membrane water electrolysis hydrogen production system is obtained by integrating multiple low-power water electrolysis hydrogen production equipment. The number of slave stations corresponds to the number of electrolyzers in the low-power water electrolysis hydrogen production equipment. The slave station is connected to the preset sensors and actuators in the system through the I / O (input / output) module. The sensor is used for real-time detection and acquisition of system operation data, and the actuator is used to maintain system operation. The slave station sends the data to the master station; then, the master station controls the slave station to perform inspection and control on the system, and obtains the inspection results. In a specific embodiment, the inspection includes detecting whether the hardware of the system is normal and the working status of the instruments or sensors in the system; then, the master station determines whether the system meets the startup conditions based on the inspection results; if so, the system is controlled to run through the slave station, and its In the process, the oxygen generated by the system is dehydrogenated, and operation data is obtained, and the operation data of the system is displayed in real time through the human-computer interaction interface. In a specific embodiment, the control system operation includes controlling the liquid level, temperature and concentration of the preset electrolyte in the preset electrolyte tank, controlling the circulation of the electrolyte between the electrolyte tank and the preset electrolytic cell, controlling the preset reaction power supply to power the electrolytic cell, dehydrogenating the oxygen generated by the anode of the electrolytic cell in the system, early purge control, controlling the thermal balance of the electrolyte in the electrolytic cell, and preventing the human-computer interaction interface from freezing. Then, the slave station is used to determine whether the operation data is normal. If so, the slave station is used to determine whether a shutdown command is received. If the slave station receives a shutdown command, the slave station performs a later purge control. If the slave station does not receive a shutdown command, the control system continues to operate through the slave station. In the whole process, corresponding indications will be given by preset indicator lights. If an abnormality occurs, the master station will perform corresponding fault processing.

[0022] In one embodiment, the step of controlling the slave station to perform inspection on the system by the master station and obtaining the inspection result further includes: Power on the preset system; Issue inspection instructions through the human-computer interaction interface; The master station controls the slave stations according to the inspection commands; The slave station collects system status data; The master station analyzes the status data and obtains the inspection results.

[0023] In this embodiment, the preset power distribution cabinet is connected to the preset main power supply, and the main control PLC controls the power distribution cabinet to distribute power to each component in the system according to demand. The preset red and green indicator lights flash for 2 seconds and then turn off, completing the power-on of the system; the human-computer interaction interface sends out an inspection instruction, and the master station controls the slave station according to the inspection command. The slave station collects the status data of the system and obtains the inspection results. In a specific embodiment, inspections are performed when the system is powered on, powered off, and in standby mode. For example, when powered on, the system is filled with nitrogen for an air tightness test; the system is purged with nitrogen to ensure that the hydrogen concentration in the hydrogen pipeline is away from the flammable and explosive range, wherein the hydrogen occupies the air. Gas volume concentration is 4% to 75.6% and is flammable and explosive; the current temperature and liquid level of the electrolyte tank are detected. If the electrolyte tank temperature is lower than 0°C, it means that the electrolyte tank has frozen and needs to be heated immediately after power-on. Starting is prohibited when the electrolyte temperature is less than 6°C, and heating is prohibited when the electrolyte water level is lower than the minimum water level; the system residual current and residual hydrogen are detected when the system is shut down, and whether each component, sensor and actuator are normal when in standby mode, which effectively improves the safety of operation; the master station determines whether the system meets the startup conditions based on the inspection results. If the startup conditions are met and there is no fault, the red light goes out; the green light flashes for 2s, turns off for 2s, and the green light lights up cyclically.

[0024] In one embodiment, if so, the step of controlling the system operation through the slave station and obtaining the operation data further includes: Issue a start command through the human-computer interaction interface; Control the liquid level, temperature, concentration and pressure of the preset electrolyte in the electrolyte tank through the slave station; Controlling the circulation of the electrolyte between the electrolyte tank and the preset electrolytic cell through the slave station; The master station controls the preset reaction power supply to supply power to the electrolytic cell; Early purge control is performed through the slave station; The heat balance of the electrolyte in the electrolysis cell is controlled by the slave station.

[0025] In this embodiment, when the system meets the startup conditions, the human-computer interaction interface issues a startup command, and the slave station controls the liquid level, temperature and concentration of the preset electrolyte in the electrolyte tank; the slave station controls the circulation of the electrolyte between the electrolyte tank and the preset electrolytic cell, and at the same time realizes the stirring of the electrolyte in the electrolytic cell; when the electrolyte circulation reaches a specific flow rate, the master station controls the preset reaction power supply to power the electrolytic cell. In a specific embodiment, the electrolytic cell is powered by a constant current; after the electrolytic cell starts to produce hydrogen, the slave station performs preliminary purge control to empty the impure hydrogen produced in the previous times, which is beneficial to ensure the purity of the hydrogen; the electric energy consumed in the water electrolysis process exceeds the theoretical heat absorption of the water electrolysis reaction, resulting in the temperature of the electrolyte in the electrolytic cell rising, so the thermal balance of the electrolyte in the electrolytic cell is controlled by the slave station to avoid damage to the anion exchange membrane caused by excessive temperature.

[0026] In one embodiment, the step of controlling the preset level, temperature, concentration and pressure of the electrolyte in the electrolyte tank by the slave station further includes: Detecting real-time operating values ​​of the electrolyte in the electrolyte tank through a preset sensor, wherein the real-time operating values ​​include a real-time liquid level value, a first real-time temperature value, a real-time concentration value, and a real-time pressure value; Collect real-time operating values ​​through slave stations; The slave station analyzes the real-time operating value according to a preset first range value and obtains a first analysis result; The slave station controls a preset actuator according to the first analysis result, so that the real-time operation value is always within a preset first range value.

[0027] In this embodiment, the real-time operating value of the electrolyte in the electrolyte tank is detected by a preset sensor. In a specific embodiment, the real-time liquid level value is detected by a liquid level sensor, the first real-time temperature value is detected by a temperature sensor, and the real-time concentration value is detected by a conductivity sensor. The slave station analyzes the real-time operating value according to a preset first range value and obtains a first analysis result, wherein the system operating state is optimal and the hydrogen production rate is highest under the preset first range value. The slave station controls the preset actuator according to the first analysis result so that the real-time operating value is always within the preset first range value. In a specific embodiment, when the electrolyte temperature in the electrolyte tank is ≤40°C, heating is started, and when the electrolyte temperature in the electrolyte tank is ≥40°C, heating is stopped; when the electrolyte temperature is 60°C and the conductivity EC is ≤50mS / cm (milliSiemens per centimeter), the corresponding alkali solution replenishment solenoid valve needs to be opened to replenish KOH (potassium hydroxide) solution, and when EC is greater than 70mS / cm, the alkali solution replenishment solenoid valve is closed; based on the electrolyte tank liquid level, when the electrolyte tank liquid level is detected to be "low", the water replenishment solenoid valve is opened in time, and when the electrolyte tank water level is detected to be "high", the water replenishment solenoid valve is closed in time.

[0028] In one embodiment, the step of controlling the circulation of the electrolyte between the electrolyte tank and the predetermined electrolytic cell by the slave station further includes: The preset water pump is controlled by the slave station to start at the preset frequency; The flow rate of the electrolyte between the electrolyte tank and the electrolytic cell is measured by a preset flow sensor, and the real-time flow value is obtained; Collect real-time flow values ​​from the station; The slave station analyzes the real-time flow value according to the preset flow value and obtains a second analysis result; The slave station controls the preset actuator according to the second analysis result until the real-time flow value reaches the preset flow value.

[0029] In this embodiment, the slave station controls the control end of the circulating water pump inverter. The inverter starts the water pump at a preset frequency. The water pump causes the electrolyte to flow between the electrolyte tank and the electrolytic cell, and stirs the electrolyte in the electrolytic cell, thereby reducing the concentration difference between the cathode and the anode. The preset flow sensor measures the flow rate of the electrolyte between the electrolyte tank and the electrolytic cell and obtains a real-time flow value. In a specific embodiment, the water pump starts with a delay of 5 seconds and then detects the flow rate of the electrolyte. The slave station analyzes the real-time flow value based on the preset flow value and obtains a second analysis result. The slave station controls the preset actuator based on the second analysis result until the real-time flow value reaches the preset flow value. In a specific embodiment, if the real-time flow value is less than the preset flow value, the slave station increases the water pump frequency to increase the flow rate of the electrolyte. If the real-time flow value is much less than the preset flow value, an abnormality is reported and the system is shut down to check whether the pipeline is blocked, whether there is any leakage in the pipeline, and whether the water pump is abnormal.

[0030] In one embodiment, the step of controlling a preset reaction power source to supply power to the electrolytic cell by the master station further includes: Outputting a preset first control voltage value through the master station and sending it to a preset reactive power supply; The reaction power supply outputs a corresponding supply voltage value and supply current value according to the first control voltage value, and is used to supply power to the electrolytic cell; The power supply current value, the power supply voltage value and the single-mode voltage value of the electrolytic cell are detected respectively by a preset current sensor, a preset first voltage sensor and a preset second voltage sensor; The master station increases or decreases the first control voltage value according to a preset frequency and amplitude, so that the supply current value and the supply voltage value reach the preset first voltage value and the preset first current value, and the single-mode voltage value is less than the preset second voltage value; Enter the preset hydrogen production percentage through the touch screen; The master station obtains the target current value based on the percentage of hydrogen production; The master station controls the reactive power supply so that the supply current value is constant and equal to the target current value.

[0031] In this embodiment, the reaction power supply adopts an output adjustable power supply, which converts the AC power provided by the distribution cabinet into DC power, and outputs the corresponding supply voltage value and supply current value according to the received first control voltage, and is used to power the electrolyzer; the supply current value, the supply voltage value and the single-mode voltage value of the electrolyzer are respectively detected by a preset current sensor, a preset first voltage sensor and a preset second voltage sensor. In a specific embodiment, the supply current value is the operating current value of the electrolyzer, and the supply voltage value is the operating voltage value of the electrolyzer. The megawatt-level anion exchange membrane water electrolysis hydrogen production system includes multiple electrolyzers, each of which is usually composed of multiple battery cells, and the voltage value of each battery cell is a single-mode voltage; the master station increases or decreases the first control voltage value according to the preset frequency and amplitude to make the supply current value and The supply voltage value reaches a preset first voltage value and a preset first current value, and the single-mode voltage value is less than a preset second voltage value. In a specific embodiment, the initial value of the preset supply voltage value and supply current value is 150V / 500A, which climbs one grid every 10s, that is, 160V / 550A, and so on to 290V / 950A, and the single-mode voltage value is <2.2V. If the single-mode voltage is ≥2.2V and the duration is >10s, a high single-mode voltage alarm is prompted; the preset hydrogen production percentage is input through the touch screen, and the main station obtains the target current value according to the hydrogen production percentage. The hydrogen production amount of electrolyzed water is positively correlated with the electrolysis current; the main station controls the reaction power supply so that the supply current value is constant and equal to the target current value. In a specific embodiment, the target current value is 850A, that is, the electrolyzer operates at a constant current of 850A.

[0032] In one embodiment, the step of performing early purge control by the slave station further includes: Detecting the gas pressure value on the cathode side of the electrolytic cell through a preset gas pressure sensor; The slave station determines whether the hydrogen pressure value reaches a preset first pressure value; If yes, the mixed gas in the system is purged and exhausted by controlling the preset actuator through the slave station; Determine whether the number of purge and emptying is equal to the preset number through the slave station; If so, shut down the actuator.

[0033] In this embodiment, after the electrolyzer starts to produce hydrogen, the slave station performs preliminary purge control to empty the hydrogen produced in the previous few times, which is beneficial to ensure the purity of the hydrogen. In a specific embodiment, the preset first pressure value is preset to 2 bar. When the gas pressure value detected by the gas pressure sensor is ≥2 bar, the slave station controls the hydrogen purge solenoid valve to be energized, and the mixed gas in the system is purged and emptied for 3 seconds and then the power is cut off; when the gas pressure value is ≥2 bar again, the hydrogen purge solenoid valve is energized again and the power is cut off after 3 seconds, achieving two hydrogen purges. After that, the hydrogen purge solenoid valve remains in the off state. If the electrolyzer operation time is ≥10 minutes and the gas pressure sensor has not detected a gas pressure value ≥2 bar, an alarm signal is output to indicate that the electrolyzer equipment has failed.

[0034] In one embodiment, the step of controlling the heat balance of the electrolyte in the electrolytic tank by the slave station further includes: Detecting the temperature of the electrolyte at the liquid outlet of the electrolytic cell by a preset sensor and obtaining a second real-time temperature value; Obtain a second real-time temperature value from the station; The slave station analyzes the second real-time temperature value according to the preset second range value and obtains a third analysis result; The slave station controls the actuator according to the third analysis result so that the second real-time temperature value is within a preset second range value.

[0035] In this embodiment, the electric energy consumed in the water electrolysis process exceeds the theoretical heat absorption of the water electrolysis reaction, resulting in an increase in the temperature of the electrolyte. If the temperature is too high, the diaphragm of the electrolysis chamber will be damaged, and it will be detrimental to the long-term operation of the equipment. The temperature value of the electrolyte at the liquid outlet of the electrolytic cell is detected by a preset temperature sensor, and the slave station analyzes the second real-time temperature value according to the preset second range value and obtains a third analysis result. The slave station controls the actuator according to the third analysis result so that the second real-time temperature value is within the preset second range value. In a specific embodiment, when the preset second range value is about 55°C to 60°C, the operating efficiency and hydrogen production of the electrolytic cell are high. A heat exchanger is set at the liquid outlet of the electrolytic cell. The heat exchanger is used to absorb the heat of the electrolyte to reduce the electrolyte temperature. The heat exchanger adopts liquid cooling to dissipate heat. The slave station increases the power of the chiller to improve the heat dissipation effect.

[0036] In one embodiment, the operating data of the system is displayed in real time through a human-computer interaction interface.

[0037] In this embodiment, the system operation data obtained from the slave station will be sent to the master station, and the master station will send the operation data to the human-machine interaction interface for display. The HMI has a self-checking function for communicating with the master PLC. When a communication abnormality occurs, the communication abnormality will be displayed on the HMI. In a specific embodiment, in order to prevent the HMI from freezing while the hydrogen production system is still working, a watchdog communication protocol is designed. Every 1 second, the HMI writes 1 to the register of the master PLC, and the master PLC delays 1.1 seconds to read and then clears it to 0. If the master PLC cannot read 1, a fault is reported, indicating that the master PLC and HMI have failed to communicate, and the system shuts down.

[0038] In one embodiment, if yes, then the step of performing a post-purge by the slave station further includes: Issue a shutdown command through the human-computer interaction interface; The main station controls the reaction power supply so that the voltage and current of the electrolytic cell are reduced to zero at a preset frequency and a preset amplitude; Detecting the gas pressure value on the cathode side of the electrolytic cell through a preset gas pressure sensor; The slave station controls the preset actuator to purge and drain the system at a preset frequency until the gas pressure value is less than a preset second pressure value.

[0039] In this embodiment, a shutdown command is input through the human-computer interaction interface, and the green indicator light flashes for 1 second, turns off for 1 second, and continues to flash; the reaction power supply is controlled by the main station to reduce the voltage and current of the electrolytic cell to zero according to a preset frequency and a preset amplitude. In a specific embodiment, the main control PLC reduces the electrolytic cell current from 850A to 800A within 1 second, and reduces it by 50A every 5 seconds. After 80 seconds, the current will be reduced to the minimum current of 10A, and the current will be set to 0A after maintaining the minimum current for 5 minutes; if the positive and negative bus voltages drop below 60V within these 5 minutes, the current can be set to 0A; in either case, the electrolytic cell current is reduced after maintaining the 0A current for 1 minute. The pressure is set to 0V; the gas pressure value on the cathode side of the electrolytic cell is detected by a preset gas pressure sensor, and the slave station controls the preset actuator to purge and empty the system at a preset frequency until the gas pressure value is less than a preset second pressure value. In a specific embodiment, the purge solenoid valve is energized for 1s, that is, the system is purged and emptied for 1s and then the power is turned off. Thereafter, the solenoid valve is energized for 1s every 2s and then the power is turned off. When the pressure of the gas pressure sensor is less than 2bar, the purge program is stopped. The solenoid valve is energized for a maximum of 10 times. If the hydrogen pressure is still greater than 2bar after 10 purges, a "purge abnormality" error is reported, the system enters standby mode, and the inspection subroutine is continuously executed.

[0040] In one embodiment, the master station controls a preset indicator light to issue a corresponding reminder, and the steps of performing corresponding fault processing further include: Analyze the fault severity level through the master station; If it is a warning, the master station will control the indicator light to give a corresponding reminder; If it is an error, the master station will perform fault shutdown control, which includes post-purge control and inspection control; If it is a fatal error, emergency shutdown control is performed through the master station, where the emergency shutdown control includes powering off the system.

[0041] In this embodiment, if an alarm message appears during the inspection and system operation, the red and green light emitting diodes flash to indicate different meanings, and the alarm message is uploaded to the host computer through the red and green indicator lights to indicate the current system status; in a specific embodiment, when the sensor detection signal is within the normal range and the system is in standby mode, the red light is off, the green light flashes for 2s, the off interval is 2s, and the green light is on in a cycle; when the sensor detection signal is within the normal range and the system is in normal working mode, the red light is off and the green light is always on; when there are general events that should be considered in the system, such as the water level in the electrolyte tank exceeds the maximum limit, in order to avoid errors or fatal errors, the red light is always on and the green light flashes or is always on to issue a warning; when there is a recoverable error in the system, such as the electrolytic cell temperature ≥65°C, the red light is always on and the green light is off, and the master station performs fault shutdown control; when there is an unrecoverable fatal error in the system and hardware maintenance is required, such as the pressure sensor is not connected or damaged, the red light flashes and the green light is off, and the master station performs emergency shutdown control.

[0042] More specifically, when a fault shutdown event occurs, the HMI displays the "fault shutdown" status, the system enters the standby state, the slave station performs post-purge control, and continues to execute the inspection subroutine; when a fatal error occurs, the master station performs emergency shutdown control. In a specific embodiment, the master station reduces the voltage and current of the electrolyzer to 0, turns off the dryer, hydrogen compressor and pure water machine, and opens the purge solenoid valve; after 1 minute, the cooling fan, circulating water pump, and cooling water pump are turned off, and the system can only wait for power to be cut off and restarted; "sound and light alarm" devices are installed at the doors of the electric compartment and hydrogen compartment. If the master station receives a smoke alarm, fire alarm signal and host computer fire signal, the master station drives the sound and light alarm devices of the corresponding electric compartment and hydrogen compartment, and immediately performs emergency shutdown control.

[0043] The present invention proposes global monitoring by the master station, and multiple slave stations quickly respond to the master station's instructions to control the system's operation and collect data, so that the entire system is in the best operating state and effectively improve the hydrogen production efficiency; the present invention proposes that the master station judge the system's operating state in real time, and promptly alarm and perform corresponding fault processing when an abnormality occurs, effectively improving the safety of the system operation.

[0044] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, apparatus, article, or method comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, apparatus, article, or method. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, apparatus, article, or method comprising the element.

[0045] The above description is only a preferred embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A control method for a megawatt-level anion exchange membrane water electrolysis hydrogen production system, characterized in that: The following steps are involved: Connect the preset master station to the preset human-machine interaction interface and the preset slave station respectively; Connecting the slave station to a preset system communication; Controlling the slave station through the master station to perform inspection control on the system and obtain inspection results; The master station determines whether the system meets the startup conditions according to the inspection results; If so, the slave station controls the operation of the system, including dehydrogenating the oxygen generated by the system and obtaining operation data; if not, the master station controls the preset indicator light to give a reminder and perform corresponding fault processing; Displaying the operating data of the system in real time through the human-computer interaction interface; Determining whether the operating data is normal by the slave station; If yes, the slave station determines whether a shutdown command has been received; if not, the master station controls the indicator light to give a reminder and performs corresponding fault processing; If so, the slave station performs a post-purge procedure on the system; if not, the slave station controls the system to continue operating.

2. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 1, characterized in that: The step of controlling the slave station to perform inspection on the system by the master station and obtaining the inspection result further includes: Powering on the system; issuing inspection instructions through the human-computer interaction interface; The master station controls the slave station according to the inspection command; The slave station collects status data of the system; The master station analyzes the status data and obtains an inspection result.

3. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 1, characterized in that: If yes, the operation of the system is controlled by the slave station, wherein the steps of removing hydrogen from the oxygen generated by the system and obtaining the operation data further include: issuing a start command through the human-computer interaction interface; Controlling the liquid level, temperature and concentration of the electrolyte in the preset electrolyte tank through the slave station; Controlling the electrolyte circulation between the electrolyte tank and a preset electrolytic cell through the slave station; The master station controls a preset reaction power source to supply power to the electrolytic cell; executing a preliminary purge procedure on the system through the slave station; The heat balance of the electrolyte in the electrolytic cell is controlled by the slave station.

4. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 3, characterized in that: The step of controlling the liquid level, temperature and concentration of the electrolyte in the electrolyte tank by the slave station further includes: Detecting real-time operating values ​​of the electrolyte in the electrolyte tank by a preset sensor, wherein the real-time operating values ​​include a real-time liquid level value, a first real-time temperature value, and a real-time concentration value; Collecting the real-time operating value through the slave station; The slave station analyzes the real-time operation value according to a preset first range value and obtains a first analysis result; The slave station controls a preset actuator according to the first analysis result, so that the real-time operation value is always within the first range.

5. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 4, characterized in that: The step of controlling the electrolyte circulation between the electrolyte tank and the preset electrolytic cell by the slave station further includes: Controlling a preset water pump to start at a preset frequency through the slave station; Measuring the flow rate of the electrolyte between the electrolyte tank and the electrolytic cell by a preset flow sensor and obtaining a real-time flow value; The slave station collects the real-time flow value; The slave station analyzes the real-time flow value according to a preset flow value and obtains a second analysis result; The slave station controls the actuator according to the second analysis result until the real-time flow value reaches the flow value.

6. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 5, characterized in that: The step of controlling a preset reaction power supply to supply power to the electrolytic cell by the master station further includes: Outputting a preset first control voltage value through the master station and sending it to a preset reaction power supply; The reaction power supply outputs a corresponding supply voltage value and supply current value according to the first control voltage value, and is used to supply power to the electrolytic cell; Respectively detecting the supply current value, the supply voltage value, and the single-mode voltage value of the electrolytic cell through a preset current sensor, a preset first voltage sensor, and a preset second voltage sensor; The master station increases or decreases the first control voltage value according to a preset frequency and a preset amplitude, so that the supply current value and the supply voltage value reach a preset first voltage value and a preset first current value, and the single-mode voltage value is less than a preset second voltage value; Inputting a preset hydrogen production percentage through the human-computer interaction interface; The master station obtains a target current value according to the hydrogen production percentage; The master station controls the reactive power supply so that the supply current value is constantly equal to the target current value.

7. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 6, characterized in that: The step of executing a preliminary purge procedure on the system by the slave station further includes: Detecting the gas pressure value on the cathode side of the electrolytic cell by a preset gas pressure sensor; The slave station determines whether the gas pressure value reaches a preset first pressure value; If so, the slave station controls the actuator to purge and exhaust the mixed gas in the system; Determining, by the slave station, whether the number of times of purge and emptying is equal to a preset number; If so, the actuator is turned off.

8. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 7, characterized in that: The step of controlling the heat balance of the electrolyte in the electrolytic tank by the slave station further includes: Detecting the temperature of the electrolyte at the liquid outlet of the electrolytic cell by a preset sensor and obtaining a second real-time temperature value; The slave station obtains the second real-time temperature value; The slave station analyzes the second real-time temperature value according to a preset second range value and obtains a third analysis result; The slave station controls the actuator according to the third analysis result so that the second real-time temperature value is within the preset second range value.

9. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 8, characterized in that: If so, the step of performing a post-purge through the slave station further includes: issuing a shutdown command through the human-computer interaction interface; Controlling the reaction power supply through the master station so that the voltage and current of the electrolytic cell are reduced to zero at a preset frequency and a preset amplitude; Detecting the gas pressure value on the cathode side of the electrolytic cell by a preset gas pressure sensor; The slave station controls the actuator to purge and drain the system at a preset frequency until the gas pressure value is less than a preset second pressure value.

10. The control method of the megawatt-level anion exchange membrane water electrolysis hydrogen production system according to claim 1, characterized in that: If not, the master station controls a preset indicator light to give a reminder, and performs corresponding fault processing, further comprising: analyzing the fault severity level by the master station; If it is a warning, the master station controls the indicator light to give a corresponding reminder; If it is an error, the fault shutdown control is performed through the master station, wherein the fault shutdown control includes post-purge control and inspection control; If it is a fatal error, an emergency shutdown is controlled by the master station, wherein the emergency shutdown control includes post-purge control and powering off the system.

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