Method and monitoring system for controlling safe operation of alkaline water electrolyzer

Abstract

The present invention relates to the technical field of alkaline water electrolyzers for hydrogen production, and in particular to a method and monitoring system for controlling the safe operation of an alkaline water electrolyzer. The method comprises: mounting at least one disc spring deformation monitoring instrument at disc springs of an alkaline water electrolyzer, so as to monitor deformation of the disc springs and provide a source of a safe operation control signal for the electrolyzer; making a control determination on the basis of a disc spring deformation amount monitored by the disc spring deformation monitoring instrument, to determine whether the electrolyzer is within a safe operation range; and when the disc spring deformation amount exceeds a specified safe use range, triggering a stop signal to stop operation of the electrolyzer. In the present invention, safety issues during operation of the electrolyzer can be effectively found, and timely determination on maintenance and treatment of the electrolyzer is made, thereby ensuring safe operation of the electrolyzer.

Description

A method and monitoring system for safe operation control of an alkaline water electrolyzer. Technical Field

[0001] This invention relates to the field of alkaline water electrolyzers for hydrogen production, specifically to a method for safe operation control of an alkaline water electrolyzer and a ranging monitoring system. Background Technology

[0002] Currently, alkaline water electrolyzers (water electrolysis hydrogen production devices) frequently experience alkali and gas leaks during operation. In severe cases, this can lead to explosions and damage to the electrolyzer. The main reason for the alkali leak is that the alkaline electrolyzer consists of a combination of gaskets and electrode frames. The main material of the gaskets is polytetrafluoroethylene (PTFE), which has poor creep resistance and will continuously thin during use. As the gaskets thin, the disc springs in the disc spring assembly, which serves as the electrolyzer's fastening device, will deform, reducing their strength and tightening force. When the tightening force (fastening force) is less than the safe zone, alkali leakage will occur in the electrolyzer.

[0003] Once the electrolyzer leaks, especially if alkali leaks during operation, the electrolyzer is prone to short circuit and burnout. In severe cases, hydrogen leakage can cause an explosion when it comes into contact with an open flame, significantly shortening the electrolyzer's service life. Therefore, it is necessary to measure and monitor the deformation of the disc springs online in real time to provide early warning of potential electrolyzer leaks, promptly shut down the machine for maintenance, or take necessary measures to address the hazards of disc spring deformation.

[0004] In addition, water electrolysis hydrogen production units are prone to the following problems during operation: During operation, the large number of stacked electrolysis chambers in the electrolyzer results in a long electrolyzer length. Since the electrolysis reaction releases heat, the internal temperature of the electrolyzer rises. Temperature changes not only affect electrolysis efficiency and gas production but also cause structural changes in the electrolyzer, particularly axial length expansion and contraction. Axial expansion and contraction significantly impact the electrolyzer's sealing performance, electrode spacing, and diaphragm performance. Axial expansion and contraction can cause stress changes in the electrolyzer's sealing gaskets, affecting the sealing effect. If the seals cannot adapt to the expansion and contraction caused by temperature changes, electrolyte leakage or gas escape may occur, affecting the system's safety and reliability. Axial expansion and contraction also affect the distance between the anode and cathode plates, i.e., the electrode spacing. Changes in electrode spacing affect the electrolyzer's resistance, thus affecting electrolysis efficiency and energy consumption. If the electrode spacing increases, the resistance increases, and the electrolysis efficiency decreases; conversely, the smaller the electrode spacing, the lower the resistance. Axial expansion and contraction of the diaphragm may affect its physical and chemical properties. If the diaphragm material cannot adapt to the expansion and contraction caused by temperature changes, it may lead to diaphragm rupture or deformation, affecting the separation efficiency of hydrogen and oxygen. Meanwhile, under normal operating conditions, the disc springs on the electrolytic cell fasteners may deform severely due to prolonged use or excessive load, resulting in increased spacing between the electrolytic cells and potential leaks.

[0005] Therefore, the distance measurement of key components of the electrolyzer is particularly important when the electrolyzer is in operation. At present, most electrolyzer distance measurement methods use manual tape measure measurement. On the one hand, the measurement accuracy is insufficient, and on the other hand, manual distance measurement may touch the electrolyzer, which may lead to safety problems. Summary of the Invention

[0006] To address the aforementioned problems, this invention proposes a method and ranging monitoring system for the safe operation control of an alkaline water electrolyzer. The aim is to provide early warning of the alkaline water electrolyzer's operating status, thereby improving the safety and service life of the alkaline water electrolyzer. The specific technical solution is as follows:

[0007] A method for safe operation control of an alkaline water electrolyzer includes installing at least one disc spring deformation monitoring instrument at the disc spring of the alkaline water electrolyzer to monitor the deformation of the disc spring and provide a source of control signal for safe operation of the electrolyzer.

[0008] The disc spring deformation monitoring instrument monitors the disc spring's axial expansion and contraction deformation.

[0009] Preferably, the disc spring deformation monitoring instrument uses one or more disc spring deformation monitoring sensors selected from infrared ranging sensors, laser ranging sensors, ultrasonic ranging sensors, and radar ranging sensors.

[0010] Preferably, the disc spring deformation monitoring instrument is a limit switch or other instrument capable of measuring distance.

[0011] Preferably, when there are two or more disc spring deformation monitoring sensors, they are arranged circumferentially at intervals, adjacent to each other, or superimposed along the alkaline water electrolysis cell near the disc spring assembly.

[0012] Preferably, the contact of the limit switch is close to one of the axially displaced parts on the alkaline water electrolysis cell caused by deformation; when the axial displacement of the axially displaced part of the alkaline water electrolysis cell exceeds a set safety threshold, the axially displaced part touches the contact of the limit switch and triggers the limit switch to operate.

[0013] In this invention, the axial displacement portion on the alkaline water electrolysis cell includes the axial displacement component in the end pressure plate and disc spring assembly.

[0014] In this invention, a disc spring deformation monitoring instrument is installed on the alkaline water electrolysis cell to monitor the expansion and contraction of the disc spring, and the disc spring deformation monitoring instrument is connected to the control system of the alkaline water electrolysis cell.

[0015] In this invention, the control system of the alkaline water electrolyzer makes a control judgment based on the amount of disc spring deformation monitored by the disc spring deformation monitoring instrument, and determines whether the electrolyzer is within the safe operating range; when the amount of disc spring deformation exceeds the specified safe operating range, a stop signal is triggered to stop the electrolyzer from operating.

[0016] A ranging and monitoring system for a water electrolysis hydrogen production device includes a left end pressure plate and a right end pressure plate. Several electrolysis chambers are disposed between the left and right end pressure plates. The left end pressure plate, a middle electrode plate, and the right end pressure plate are tightened together by multiple long bolts to form the electrolysis cell body. One end of each long bolt is equipped with a disc spring assembly. Pre-set monitoring points are arranged in pairs on the monitoring section of the electrolysis cell body. The system also includes a detection signal transmitting module or a detection signal receiving module disposed at the preset monitoring points. The detection signal transmitting module is used to emit a non-contact measurement detection signal, and the detection signal receiving module is used to receive the detection signal. The system also includes a time measurement module and a data processing module. The detection signal transmitting module emits the detection signal, and the detection signal receiving module receives the detection signal. Simultaneously, a trigger signal is generated to the time measurement module. The time measurement module calculates the time interval t between the two trigger signals, which is the flight time of the detection signal. The data processing module calculates the distance l of the monitoring points based on the time interval t and the propagation speed v of the detection signal. The system also includes a temperature detection unit that monitors the temperature T of the electrolytic cell body while performing distance detection. Furthermore, a comparison processing system is included, which has a database of theoretical distances L for monitoring points at different temperatures of the electrolytic cell body. The comparison processing system receives the electrolytic cell body temperature T and the calculated distance l, compares it with the range of theoretical distances L corresponding to the temperature in the database, and triggers an alarm system when the distance l exceeds the range of the theoretical distance L.

[0017] Furthermore, the detection signal transmitting module is an ultrasonic ranging sensor, a laser ranging sensor, or a radar ranging sensor.

[0018] Furthermore, the comparison processing system is connected to the PLC control system of the electrolytic hydrogen production unit, so that the PLC control system of the electrolytic hydrogen production unit triggers the corresponding interlock based on the comparison processing result; or the PLC control system of the electrolytic hydrogen production unit issues a detection command to trigger the ranging monitoring system to perform periodic detection.

[0019] Furthermore, the detection signal transmitting module and the detection signal receiving module are located at the same preset monitoring point, and a reflective component is provided at another preset monitoring point corresponding to this preset monitoring point.

[0020] Furthermore, the detection signal transmitting module and the detection signal receiving module are respectively set at two preset monitoring points of the monitoring location.

[0021] Furthermore, the preset monitoring point is equipped with a positioning frame structure for mounting the detection signal transmitting module or the detection signal receiving module.

[0022] An application of a distance measurement and monitoring system for a water electrolysis hydrogen production device involves setting up a positioning frame structure on the left and right end pressure plates, and using the distance measurement and monitoring system to monitor the distance change between the two end pressure plates.

[0023] An application of a distance measurement and monitoring system for a water electrolysis hydrogen production device involves setting a positioning frame structure on any one end plate and setting another positioning frame structure on the pole frame of a certain electrolysis cell, and using the distance measurement and monitoring system to monitor the distance change between the end plate and the predetermined electrolysis cell.

[0024] An application of a ranging monitoring system for a water electrolysis hydrogen production device involves setting positioning frame structures on the insulating pads on both sides of the disc spring assembly at the end of a long bolt, and using the ranging monitoring system to monitor the dimensional changes of the disc spring assembly.

[0025] The beneficial effects of this invention are:

[0026] First, the method and ranging monitoring system for safe operation control of an alkaline water electrolyzer of the present invention can effectively detect safety problems during the operation of the electrolyzer, make timely judgments on maintenance and treatment of the electrolyzer, ensure the safe operation of the electrolyzer, and help improve the service life of the alkaline water electrolyzer.

[0027] Secondly, the present invention provides a ranging monitoring system for a water electrolysis hydrogen production device, which can autonomously or automatically monitor the electrolyzer body (internal spacing of the end pressure plates) and / or the size change of the electrolyzer disc spring during operation. The present invention detects the distance between two preset monitoring points using non-contact methods such as ultrasound, laser, and radar, and has online monitoring and interlocking functions, which is beneficial for automatic equipment control. When the size change is large and the disc spring compensation capacity is insufficient, it can provide early warning of possible leakage in the electrolyzer. The ultrasonic ranging fixed-point detection system used in this device can measure without contact, with high precision, fast response, and strong anti-interference ability. It can be directly connected to the PLC control system of the electrolysis hydrogen production device to perform interlocking reactions to protect the entire device. Attached Figure Description

[0028] Figure 1 is a schematic diagram of the structure of an alkaline water electrolyzer in the prior art;

[0029] Figure 2 is a schematic diagram of the structure of a disc spring deformation monitoring sensor (distance sensor) installed at the disc spring of the electrolyzer as a disc spring deformation monitoring instrument in a method for safe operation control of an alkaline water electrolyzer according to the present invention.

[0030] Figure 3 is a schematic diagram of the structure of a disc spring deformation monitoring sensor (distance sensor) and a limit switch installed at the disc spring of the electrolyzer as a disc spring deformation monitoring instrument in a method for safe operation control of an alkaline water electrolyzer according to the present invention.

[0031] Figure 4 is one of the overall principle schematic diagrams of a ranging and monitoring system for a water electrolysis hydrogen production device according to the present invention;

[0032] Figure 5 is a second schematic diagram of the overall principle of a ranging and monitoring system for a water electrolysis hydrogen production device according to the present invention.

[0033] Figure 6 is a schematic diagram of the installation structure of a ranging and monitoring system for a water electrolysis hydrogen production device according to the present invention.

[0034] Figure 7 is a schematic diagram of the installation of the positioning frame structure in Embodiment 5 of the present invention;

[0035] Figure 8 is a structural schematic diagram of section AA in Figure 4 of the present invention;

[0036] Figure 9 is a schematic diagram of the installation of the positioning frame structure in Embodiment 6 of the present invention;

[0037] Figure 10 is a structural schematic diagram of section AA in Figure 6 of the present invention;

[0038] Figure 11 is a schematic diagram of the installation of the positioning frame structure in Embodiment 7 of the present invention;

[0039] Figure 12 is a structural schematic diagram of section AA in Figure 7 of the present invention;

[0040] In Figures 1-3: 51. Tensioning screw, 52. End pressure plate, 53. Disc spring assembly, 54. Disc spring, 55. Disc spring deformation monitoring sensor (distance sensor), 56. Surface to be tested, 57. Insulating gasket, 58. Fixing ring, 59. Guide ring with pressure flange, 60. Washer, 61. Nut, 62. Insulating sleeve, 63. Limit switch, 68. End plate, 69. Insulating plate, 70. Electrode plate, 71. Sealing gasket, 72. Oxygen evolution electrode, 73. Hydrogen evolution electrode, 74. Diaphragm.

[0041] In Figure 2: A is one end of the disc spring assembly, and B is the other end of the disc spring assembly.

[0042] In Figures 4-12: 1. Electrolytic cell body; 2. Left end pressure plate; 3. Right end pressure plate; 4. Long bolt; 5. Disc spring assembly; 6. Preset monitoring point; 7. Detection signal transmission module; 8. Detection signal receiving module; 9. Distance monitoring system; 10. Reflecting component; 11. Positioning frame structure; 12. Slot; 13. First side plate; 14. Second side plate; 15. Base plate; 16. U-shaped bayonet; 17. Fastening bolt; 18. Reinforcing rib; 19. Guide rail; 20. Slider; 21. Vertical plate; 22. Nut; 23. Adjusting screw; 24. Arc-shaped base plate; 25. First hinge arm; 26. Second hinge arm; 27. Positioning screw; 28. Threaded hole; 29. ​​Sensor; 30. Insulating pad; 31. Collar; 32. Pole frame. Detailed Implementation

[0043] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0044] Example 1-1:

[0045] Referring to Figure 1, a typical structure of an alkaline water electrolyzer that produces hydrogen by electrolyzing alkaline water is shown. It includes a number of electrode plate parts (including electrode plate 70 and end electrode plate 68) assembled by stacking. A sealing gasket 71 is provided between adjacent electrode plate parts. The two ends of the alkaline water electrolyzer after stacking are axially tightened and fixed by end pressure plate 52, tensioning screw 51, disc spring 54, nut 61, etc. The tensioning screw 51, fixing ring 58, multiple disc springs 54, guide ring 59 with pressure flange, nut 61, and washer 60 constitute the disc spring assembly 53 on the alkaline water electrolyzer for axially pressing the end pressure plate 52.

[0046] Examples 1-2:

[0047] Figures 1 to 3 show an embodiment of a method for safe operation control of an alkaline water electrolyzer according to the present invention, which includes installing at least one disc spring deformation monitoring instrument at the disc spring 54 of the alkaline water electrolyzer to monitor the deformation of the disc spring 54 and provide a source of control signal for safe operation of the electrolyzer.

[0048] The disc spring deformation monitoring instrument monitors the disc spring 54, including the axial expansion and contraction deformation of the disc spring 54.

[0049] Preferably, the disc spring deformation monitoring instrument uses one or more disc spring deformation monitoring sensors 55 selected from infrared ranging sensors, laser ranging sensors, ultrasonic ranging sensors, and radar ranging sensors.

[0050] Preferably, the disc spring deformation monitoring instrument uses a limit switch 63 or other instruments capable of measuring distance.

[0051] Preferably, the disc spring deformation monitoring sensors 55 are arranged circumferentially, adjacently, or superimposed along the alkaline water electrolysis cell near the disc spring assembly 53 when there are equal or more than two such sensors.

[0052] Preferably, the contact of the limit switch 63 is close to one of the axially displaced parts on the alkaline water electrolysis cell caused by deformation; when the axial displacement of the axially displaced part of the alkaline water electrolysis cell exceeds the set safety threshold, the axially displaced part touches the contact of the limit switch 63 and triggers the limit switch 63 to operate.

[0053] In this embodiment, the axial displacement portion on the alkaline water electrolysis cell includes the axial displacement component in the end pressure plate 52 and the disc spring assembly 53.

[0054] In this embodiment, a disc spring deformation monitoring instrument is installed on the alkaline water electrolysis cell to monitor the expansion and contraction of the disc spring. The disc spring deformation monitoring instrument is connected to the control system of the alkaline water electrolysis cell.

[0055] In this embodiment, the control system of the alkaline water electrolyzer makes a control judgment based on the amount of disc spring deformation monitored by the disc spring deformation monitoring instrument, and determines whether the electrolyzer is within the safe operating range; when the amount of disc spring deformation exceeds the specified safe operating range, a stop signal is triggered to stop the electrolyzer from operating.

[0056] The beneficial effects of this embodiment are: it can effectively detect safety problems during the operation of the electrolytic cell, make timely judgments on the maintenance of the electrolytic cell, and ensure the safe operation of the electrolytic cell.

[0057] Examples 1-3:

[0058] Referring to Figure 2, a system for safe operation control of an alkaline water electrolyzer is set up based on the alkaline water electrolyzer in Figure 1. The system includes a tensioning screw 51 installed on the alkaline water electrolyzer, a disc spring assembly 53 installed at the end of the tensioning screw 51 for pressing the end plate 52, and a disc spring deformation monitoring sensor 55 for monitoring the axial extension and contraction deformation of the disc spring in the disc spring assembly 53. The disc spring deformation monitoring sensor 55 is connected to the control system of the alkaline water electrolyzer.

[0059] When the axial extension and contraction deformation of the disc spring in the disc spring assembly 53 exceeds the set safety threshold, the control system issues an alarm message and controls the alkaline water electrolysis cell to stop operating.

[0060] As one of the preferred solutions for the disc spring deformation monitoring sensor in this embodiment, the disc spring deformation monitoring sensor 55 is a distance measuring sensor. The distance measuring sensor monitors the magnitude of the axial expansion and contraction deformation of the disc spring by means of the following installation method: the distance measuring sensor is set at one end (A or B) near the two ends of the disc spring assembly 53 along the axial direction, and the detection surface 56 is set at the other end (B or A) near the two ends of the disc spring assembly 53 along the axial direction. The detection probe of the distance measuring sensor is pointed axially towards the detection surface 56, thereby monitoring the magnitude of the change in the axial relative distance between the two ends of the disc spring assembly 53, and thus monitoring the magnitude of the axial expansion and contraction deformation of the disc spring.

[0061] Preferably, there are multiple disc spring deformation monitoring sensors 55 arranged circumferentially around the alkaline water electrolysis cell near the disc spring assembly 53.

[0062] More preferably, the ranging sensor is one of an infrared ranging sensor, a laser ranging sensor, an ultrasonic ranging sensor, or a radar ranging sensor.

[0063] In this embodiment, the disc spring assembly 53 includes an insulating gasket 57, a retaining ring 58, a number of disc springs 54, a guide ring 59 with a pressure flange, a washer 60, and a nut 61, which are stacked and connected in sequence and are sleeved on the end of the tensioning screw 51. The insulating gasket 57 abuts against the outer surface of the end pressure plate 52 of the alkaline water electrolysis cell. The end pressure plate 52, the insulating gasket 57, and the retaining ring 58 are one end of the disc spring assembly 53, which is close to both axial ends. The guide ring 59 with the pressure flange, the washer 60, the nut 61, and the shaft end of the tensioning screw 51 are the other end of the disc spring assembly 53.

[0064] In other words, the ranging sensor in this embodiment can be flexibly installed on any part of one of the two axial ends of the disc spring assembly 53, and then the detection probe of the ranging sensor is pointed axially towards the detection surface of the corresponding part of the other axial end of the disc spring assembly 53. These parts include the end pressure plate 52, insulating gasket 57 and retaining ring 58 located at one end, and the guide ring 59 with pressure flange, washer 60, nut 61 and the shaft end of the tensioning screw 51 located at the other end, and the disc spring 54 that is in contact with the retaining ring 58 or the guide ring 59 with flange, which has a local rigid part.

[0065] Preferably, a detection reference plate can be provided on these parts, which is positioned directly opposite the ranging sensor, and the surface to be detected can be placed on the detection reference plate.

[0066] In Figure 2, the surface to be tested is directly set on the plane of the end pressure plate; in Figure 3, a testing reference plate is set on the guide ring 59 of the pressure flange, and the surface to be tested is set on the plane of the testing reference plate. It should be noted that the testing reference plate can also be set on other axial displacement parts of the disc spring assembly, and its connection can be an assembly connection or an integrated connection with the axial displacement parts of the disc spring assembly 53.

[0067] As a second preferred embodiment of the disc spring deformation monitoring sensor, the disc spring deformation monitoring sensor 55 is a visual recognition camera (not shown in the figure) located on one radial side of the disc spring assembly 53, with the camera probe of the visual recognition camera aligned with the disc spring assembly 53.

[0068] During operation, the control system of the alkaline water electrolyzer captures images of the disc spring assembly 53 online through the visual recognition camera and identifies and analyzes the axial dimensions of the disc spring 54 part in the disc spring assembly 53, thereby realizing the monitoring of the magnitude of the axial expansion and contraction deformation of the disc spring.

[0069] As a third preferred embodiment of the disc spring deformation monitoring sensor in this example, the disc spring deformation monitoring sensor 55 is a limit switch 63 disposed next to the disc spring assembly 53 to limit the amount of disc spring deformation; the contact of the limit switch 63 is close to one of the axial displacement parts on the alkaline water electrolysis cell caused by thermal deformation, the axial displacement part on the alkaline water electrolysis cell includes the end pressure plate 52 and the axial displacement component in the disc spring assembly 53; when the axial displacement of the axial displacement part of the alkaline water electrolysis cell exceeds the set safety threshold, the axial displacement part touches the contact of the limit switch 63 and triggers the limit switch 63 to act, and the control system of the alkaline water electrolysis cell controls the electrolysis cell to stop operating, ensuring the safety of the electrolysis cell.

[0070] Preferably, the limit switch can also be replaced by a proximity switch. When the axial displacement of the axial displacement part of the alkaline water electrolyzer exceeds the set safety threshold, the axial displacement part approaches the limit switch and sends proximity information to the control system of the alkaline water electrolyzer. The control system of the alkaline water electrolyzer then controls the electrolyzer to stop operating, ensuring the safety of the electrolyzer.

[0071] The axial displacement components in the disc spring assembly 53 include the insulating gasket 57, the disc spring 54, and the retaining ring 58.

[0072] The axial displacement of the aforementioned alkaline water electrolyzer corresponds to the axial deformation of the disc spring 54. Therefore, by setting the limit switch 63, the electrolyzer can be shut down in time when the deformation of the disc spring exceeds the preset safety threshold, thereby ensuring the safe operation of the electrolyzer.

[0073] Referring to Figure 3, the contacts of the limit switch 63 are located near the end plate plane of the alkaline water electrolyzer. When the alkaline water electrolyzer expands due to heat, the end plate 52 on the alkaline water electrolyzer undergoes axial displacement, causing the disc spring 54 to deform axially. When the axial displacement of the end plate (corresponding to the axial deformation of the disc spring 54) exceeds a set safety threshold, the end plate will touch the contacts of the limit switch 63 due to the axial displacement, triggering the limit switch 63 to operate. The control system then stops the alkaline water electrolyzer. After the limit switch 63 resets, the control system restarts the alkaline water electrolyzer for normal operation.

[0074] It should be noted that the contacts of the limit switch 63 can also be set on the axial displacement part in the disc spring assembly 53 (for example, on the guide ring 59 of the pressure flange). In this case, the outer diameter of the corresponding axial displacement part can be appropriately enlarged or an extended reference plate that expands along the outer diameter direction can be set on the corresponding axial displacement part to facilitate the contact of the limit switch 63 to be aligned with the enlarged surface of the corresponding axial displacement part.

[0075] Implementation 2-1:

[0076] Figures 4 to 12 illustrate an embodiment of a ranging monitoring system for a water electrolysis hydrogen production device. The system includes a left end pressure plate 2 and a right end pressure plate 3. Several electrolysis chambers are arranged between the left end pressure plate 2 and the right end pressure plate 3. The left end pressure plate 2, the intermediate electrode plate, and the right end pressure plate 3 are tightened together by multiple long bolts 4 to form an electrolytic cell body 1. One end of each long bolt 4 is equipped with a disc spring assembly 5. Preset monitoring points 6 are arranged in pairs on the monitoring section of the electrolytic cell body 1. The system also includes a detection signal transmitting module 7 or a detection signal receiving module 8 set at the preset monitoring points 6. The detection signal transmitting module 7 is used to emit a non-contact measurement detection signal. In this embodiment, the detection signal transmitting module 7 and the detection signal receiving module 8 are placed at the same end, while the detection target is located at another opposite preset monitoring point 6, as shown in Figure 6. The detection signal transmitting module 7 and the detection signal receiving module 8 are located at the same preset monitoring point 6, and a reflective component 10 is provided at the other preset monitoring point 6 corresponding to this preset monitoring point 6. The detection signal transmitting module 7 is an ultrasonic ranging sensor 29. In this embodiment, it is based on the pulse-echo method, as shown in Figure 4. The trigger signal of the control circuit excites the detection signal transmitting module 7 to generate an ultrasonic pulse. At the same time, the system generates a start signal and transmits it to the time measurement module. When the ultrasonic wave is transmitted to the object and encounters the object's obstruction, it generates a pulse echo. The detection signal receiving module 8 is used to receive the detection signal. The detection signal receiving module 8 receives the signal and simultaneously sends an end signal to the time measurement module. That is, the detection signal transmitting module 7 emits the detection signal and the detection signal receiving module 8 receives the detection signal. Simultaneously, a trigger signal is generated to the time measurement module for each of the two signals. The time measurement module digitizes the time difference between the two signals and calculates the time interval t between the two trigger signals, which is the flight time of the detection signal. This matches the flight time of the ultrasound. Combined with the speed of sound v (the speed of sound in air can be calculated; assuming a constant air temperature of 15℃, the speed of sound is approximately 340m / s), the distance l between the signal transmitter and the target, i.e., the distance between the two preset monitoring points 6, is calculated by the data processing module based on the time interval t and the speed of sound v, as shown in the following formula:

[0077] .

[0078] It also includes a temperature detection unit that monitors the temperature of the electrolytic cell body 1. While performing distance detection, the temperature T of the electrolytic cell body 1 is measured. The temperature detection unit measures the temperature of the environment in which the electrolytic cell body 1 is located. This can be used to calculate the speed of sound waves in that environment, and also to monitor the temperature of the electrolytic cell body 1 for subsequent comparative processing to correspond to the relationship between the temperature and the elongation of the electrolytic cell.

[0079] Specifically, temperature has a certain impact on the accuracy of ultrasonic ranging. Generally, for every 1°C change in temperature, the speed of sound changes by 0.607 m / s. The change in temperature affecting the ultrasonic wave speed is compensated for in the ultrasonic wave velocity as a correction, reducing the influence of temperature conditions on the ranging results and improving the accuracy of this ultrasonic detection system. This ultrasonic ranging system includes a temperature compensation component, which corrects the ultrasonic wave propagation speed by acquiring the medium temperature, thereby improving ranging accuracy. The propagation speed of ultrasound in actual working conditions is calculated by the following formula:

[0080] .

[0081] In the formula: t is the temperature of the air medium, in °C; T0 is a constant, and T0 = 273.16; v is in m / s.

[0082] In this embodiment, temperature data under actual working conditions is collected by a temperature detection unit, and the sound velocity is corrected, thereby improving the accuracy of ranging. In this embodiment, the ultrasonic ranging monitoring system 9 has a measuring range of 20mm to 10m; the ranging accuracy error is ±0.025mm.

[0083] Furthermore, it also includes a comparison processing system, as shown in Figure 4. The comparison processing system has a database of theoretical spacing L of monitoring points corresponding to different temperatures of the electrolytic cell body. In actual operation, since the working temperature of the electrolytic cell body 1 varies within a certain range, the elongation of the electrolytic cell body 1 also varies with the temperature. For example, the long bolts 4 connected between the two end plates are pre-tightened to the appropriate torque at the factory, ensuring that the distance between the end plates is the original factory-calibrated length. However, during operation, the electrolytic cell body 1 is affected by changes in operating conditions and environment, and thermal expansion and contraction cause the distance between the end plates to change with temperature. Based on long-term practical experience, the temperature changes during the operation of the electrolytic cell body 1 are compiled into a temperature gradient for reference. When a certain temperature value in the temperature gradient is reached, the distance between the end plates should be within a certain range. The comparison processing system receives the temperature T of the electrolytic cell body 1 and the calculated distance l, and compares it with the theoretical distance L range corresponding to the temperature in the database. When the distance l exceeds the range of the theoretical distance L, the alarm system is triggered. In actual operation, the temperature detection unit, as mentioned above, detects and evaluates the temperature of the electrolytic cell body 1, and transmits the verified temperature data to the comparison processing system. From the temperature gradient, the corresponding temperature value is selected, and the distance range of the end pressure plate under that temperature gradient can be found. The data processing module also transmits the actual distance l measured by the ultrasonic ranging system to the comparison processing system, comparing the theoretical distance L with the actual distance l. If the actual distance is within the range of the theoretical distance, the change in the distance of the end pressure plate is normal. If it exceeds the range of the theoretical distance, there may be a risk of leakage. At this time, an alarm signal can be issued to the operator through the connected alarm system.

[0084] In a preferred embodiment, the comparison processing system is connected to the PLC control system of the electrolytic hydrogen production device. The distance values ​​of the two preset monitoring points 6 measured by the aforementioned ultrasonic ranging monitoring system 9 can be transmitted to the display panel of the PLC control system for observation by the system operator. The measured distance values ​​and comparison results can also serve as conditions for the PLC to trigger interlocks, so that the PLC control system of the electrolytic hydrogen production device can trigger corresponding interlocks based on the comparison processing results. Specific interlock operations include, but are not limited to, reducing the power of the electrolyzer, increasing or decreasing the electrolyte supply flow, emergency shutdown, etc.

[0085] In practice, the distance measurement system 9 can measure the distance between two preset monitoring points 6 at a certain interval, or it can be triggered by the PLC control system of the electrolytic hydrogen production unit to perform the detection.

[0086] Example 2-2:

[0087] Similar to the principle of Embodiment 1 above, in this embodiment, the detection signal transmitting module and the detection signal receiving module in the ranging monitoring system are respectively located at two preset monitoring points, with the detection signal transmitting module and the detection signal receiving module arranged opposite to each other, as shown in Figure 7. The detection signal transmitting module and the detection signal receiving module are respectively set at two preset monitoring points of the monitoring location. Then, the distance between the two preset monitoring points is l = v × t.

[0088] Examples 2-3:

[0089] Understandably, in practical applications, laser rangefinders can be used to replace ultrasonic sensors, using optical signals as the detection signal for non-contact measurement. Specifically, d represents the distance to be measured between two preset monitoring points, c is the speed of light (approximately 3 × 10⁸ m / s in the atmosphere), and t is the flight time of the laser pulse from emission to reception, i.e., the time interval between the start and stop signals. In a pulsed laser rangefinder system, the time interval t is recorded by the clock counter inside the time measurement module, which counts the number of clock oscillator cycles between the start and stop signals. The frequency of the oscillator determines the time resolution of the counter. Assuming the clock oscillator frequency is f, and the clock counter records N oscillation cycles, the distance d can be calculated using the following formula:

[0090] .

[0091] Examples 2-4:

[0092] Understandably, in practical applications, radar ranging sensors can also be used to replace ultrasonic waves, using electromagnetic wave signals as the detection signal for non-contact measurement; the propagation speed of electromagnetic waves is approximately the speed of light, or about 300,000 kilometers per second. Radar ranging sensor systems can calculate the distance to a target by measuring the time difference between the transmitted signal and the received echo signal. Based on the time difference and the speed of electromagnetic waves, the distance can be calculated using the formula:

[0093] D = (c × t) / 2

[0094] Calculate the distance to the target. Here, D is the distance, c is the speed of electromagnetic wave propagation (approximately 3 × 10^8 meters / second), and t is the time difference between transmission and reception. Dividing by 2 is because the electromagnetic wave makes one round trip.

[0095] Examples 2-5:

[0096] As one application embodiment of the ranging monitoring system, the preset monitoring point 6 is equipped with a positioning frame structure 11 for mounting the detection signal transmitting module 7 or the detection signal receiving module 8. Specifically, in this embodiment, the positioning frame structure 11 is used to monitor the distance between the two end pressure plates of the electrolytic cell body, as shown in Figure 7. The positioning frame structure 11 is set on the left end pressure plate 2 and the right end pressure plate 3. The monitoring point is the distance between the two end pressure plates, and the two end pressure plates are the preset monitoring points 6. The ranging monitoring system 9 is used to monitor the distance change between the two end pressure plates.

[0097] The positioning frame structure 11 includes a groove 12 that is fixed to the end pressure plate and matches the shape of the end pressure plate. The groove matches the shape of the edge of the end pressure plate. In specific use, if the electrolytic cell body is a circular flange-shaped pressure plate, the groove 12 is also an arc-shaped structure, as shown in Figure 8. One side of the groove 12 is provided with a first side plate 13, and the opposite side is a second side plate 14. Between the two side plates is a bottom plate 15 that fits against the edge of the end pressure plate. The bottom plate 15 and the two side plates form a groove-shaped groove 12. Specifically, the first side plate 13 is provided with a U-shaped notch 16 that matches the position of the flange hole on the end pressure plate. When the slot 12 is engaged with the end plate, the U-shaped latch 16 is engaged with at least two long bolts 4. The number of U-shaped latches 16 is not less than two, so that the first side plate 13 can use the positions of the two long bolts 4 to position the slot 12. On the other side, the second side plate 14 is screwed with a fastening bolt 17. It can be understood that the distance between the first side plate 13 and the second side plate 14 is greater than the thickness of the end plate. When the slot 12 is engaged, it is tightened with the fastening bolt 17, thereby forming a clamping and fixing shape on the end plate. Thus, the positioning frame structure 11 can be conveniently installed on the end plate of the electrolytic cell body.

[0098] As a preferred embodiment, as shown in FIG7, side plates extend from both sides of the base plate 15 to form extended side edges, so that the base plate 15 plus the two extended side edges form a widened slot 12. A triangular reinforcing rib 18 is provided between the extended side edge and the two side plates to prevent deformation during clamping; at the same time, the extended side edge also facilitates the position adjustment of the detection signal transmission module 7 installed on the upper side.

[0099] Specifically, a guide rail 19 is provided on the upper side of the widened slot 12, which is arranged along the axial direction of the electrolytic cell body. A slider 20 is slidably arranged on the guide rail 19. The transmitting and receiving modules of the ranging detection system are installed on the slider 20. Specifically, a vertical plate 21 is arranged on the slider 20. The vertical plate 21 has a through hole. The sensor 29 of the ranging monitoring system 9 is installed through the through hole. Nuts 22 are provided on both sides of the through hole and screwed to the sensor 29 for fixing. An adjusting screw 23 is also provided. The adjusting screw 23 is arranged parallel to the guide rail 19 and rotatably connected to the slot 12. The adjusting screw 23 passes through the slider 20 and is threaded. Therefore, by rotating the adjusting screw 23, the position of the sensor 29 can be precisely adjusted so that the transmitting window of the sensor 29 is flush with the end face of the end pressure plate, thereby minimizing the measurement error.

[0100] Examples 2-6:

[0101] An application of a distance measurement and monitoring system 9 for a water electrolysis hydrogen production device is described. A positioning frame structure 11 is set on any one end plate, as shown in Figure 9. Another positioning frame structure 11 is set on the pole frame 32 of a certain electrolysis chamber. The distance measurement and monitoring system 9 is used to monitor the distance change between the end plate and the predetermined electrolysis chamber.

[0102] In this embodiment, as shown in Figure 9, the left end plate is a preset monitoring point 6, and a certain pole frame 32 on the right is another preset monitoring point 6. Therefore, positioning frame structures 11 are set at these two points respectively. The positioning frame structure 11 on the left point is the same as the structure in Embodiment 5, while the positioning frame structure 11 on the right includes an arc-shaped base plate 24, a first hinge arm 25, and a second hinge arm 26, as shown in Figure 10. The arc-shaped base plate 24 is attached to the surface of the pole frame 32, and its bottom surface has the same curvature as the surface of the pole frame 32. The surface of the pole frame 32 is provided with a threaded hole 28, and a positioning screw 27 is provided through the arc-shaped base plate 24. The positioning screw 27 is screwed into the threaded hole 28 to fix the positioning frame structure 11 to the pole frame 32. It can be understood that the pole frame 32 of each small chamber can be preset with threaded holes 28 for installation, so as to facilitate the installation of the sensor 29.

[0103] The surface of the arc-shaped substrate 24 is provided with a hinge seat. The lower end of the first hinge arm 25 is hinged to the hinge seat, and the upper end is hinged to the second hinge arm 26. The other end of the second hinge arm 26 is provided with a vertical plate 21, and a sensor 29 is provided on the vertical plate 21. In this way, by setting two hinge arms, the position of the sensor 29 in the up-down and left-right directions can be easily adjusted so that it can be set opposite to the sensor 29 on the other side.

[0104] Examples 2-7:

[0105] An application of a ranging monitoring system 9 for a water electrolysis hydrogen production device involves setting positioning frame structures 11 on the insulating pads 30 on both sides of the disc spring assembly 5 at the end of the long bolt 4, and using the ranging monitoring system 9 to monitor the dimensional changes of the disc spring assembly 5. In this embodiment, setting the ranging monitoring system 9 on the disc spring assembly 5 facilitates monitoring the compression or rebound of the disc spring, and thus allows for the determination of the expansion and contraction allowance of the electrolytic cell body.

[0106] In addition to the stacked disc springs, the disc spring assembly 5 has annular insulating pads 30 at both ends of the disc springs. By setting sensors 29 on the two insulating pads 30, it is easy to monitor the changes in the disc spring assembly 5. Specifically, as shown in Figures 11 and 12, the positioning frame in this embodiment is a collar 31. The inner diameter of the collar 31 is larger than that of the insulating pad 30. A vertical plate 21 is provided on the outer wall of the collar 31, and a sensor 29 is set on the vertical plate 21. Multiple positioning screws 27 are screwed through the collar 31. The positioning screws 27 are distributed circumferentially. During installation, the collar 31 is put on the corresponding insulating pad 30, and then the positioning screws 27 around the collar are gradually tightened so that the positioning screws 27 are pressed against the insulating pad 30, thereby fixing the positioning frame structure 11. The distance between the two sides is measured using a distance measuring detection system.

[0107] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for safe operation control of an alkaline water electrolyzer, characterized in that, The device includes installing at least one disc spring deformation monitoring instrument at the disc spring of the alkaline water electrolyzer to monitor the deformation of the disc spring and provide a source of control signals for safe operation of the electrolyzer.

2. The method for safe operation control of an alkaline water electrolyzer according to claim 1, characterized in that, The disc spring deformation monitoring instrument monitors the disc spring's axial expansion and contraction deformation.

3. The method for safe operation control of an alkaline water electrolyzer according to claim 1, characterized in that, The disc spring deformation monitoring instrument uses one or more disc spring deformation monitoring sensors, including infrared ranging sensors, laser ranging sensors, ultrasonic ranging sensors, and radar ranging sensors.

4. The method for safe operation control of an alkaline water electrolyzer according to claim 1, characterized in that, The disc spring deformation monitoring instrument uses a limit switch or other instruments that can be used to measure distance.

5. The method for safe operation control of an alkaline water electrolyzer according to claim 3, characterized in that, When there are two or more disc spring deformation monitoring sensors, they are arranged circumferentially, adjacently, or superimposed along the alkaline water electrolysis cell near the disc spring assembly.

6. The method for safe operation control of an alkaline water electrolyzer according to claim 4, characterized in that, The limit switch contacts are close to one of the axially displaced parts on the alkaline water electrolysis cell caused by deformation; when the axial displacement of the axially displaced part of the alkaline water electrolysis cell exceeds the set safety threshold, the axially displaced part touches the limit switch contacts and triggers the limit switch to operate.

7. The method for safe operation control of an alkaline water electrolyzer according to claim 6, characterized in that, The axial displacement portion on the alkaline water electrolysis cell includes the axial displacement parts in the end pressure plate and disc spring assembly.

8. The method for safe operation control of an alkaline water electrolyzer according to claim 1, characterized in that, The control judgment is made based on the amount of disc spring deformation monitored by the disc spring deformation monitoring instrument to determine whether the electrolytic cell is within the safe operating range; when the amount of disc spring deformation exceeds the specified safe operating range, a stop signal is triggered to stop the electrolytic cell from operating.

9. A ranging monitoring system for safe operation control of an alkaline water electrolyzer, characterized in that, A disc spring deformation monitoring instrument is installed on the alkaline water electrolysis cell to monitor the deformation of the disc spring. The disc spring deformation monitoring instrument is connected to the control system of the alkaline water electrolysis cell.

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