A non-contact sensing system for leak detection in hydrogen storage and its leak detection method

Abstract

This invention relates to the field of hydrogen storage leak prevention technology, and in particular to a non-contact sensing system and leak detection method for hydrogen storage leak detection. The system includes a hydrogen storage module, a detection module, a gas path system, and a smart terminal. The hydrogen storage module is connected via the gas path system to form a closed loop. The detection module is embedded in both the hydrogen storage module and the gas path system to detect leaks, and is electrically connected to the smart terminal. This invention uses a pressure detection unit in the detection module to detect pressure changes at multiple locations within the hydrogen storage module. The smart terminal analyzes the collected detection data and then determines whether to use the gas detection module for component analysis. This ensures accurate problem detection while reducing the inefficiency and delayed problem detection caused by the generalized global detection in existing technologies.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage leak prevention technology, and in particular to a non-contact sensing system for leak detection in hydrogen storage and its leak detection method. Background Technology

[0002] Research on leakage problems in hydrogen storage technology, taking existing technologies as an example, mostly focuses on timely detection, effective prevention, and safe handling; referring to the following patented technologies:

[0003] Patent 1: A hydrogen leakage monitoring and protection device and method for a hydrogen power generation device, authorized announcement number CN108758355B;

[0004] A hydrogen leakage monitoring and protection device and method for a hydrogen power generation unit includes: installing a fume extraction hood directly above each valve of the hydrogen power generation unit to collect hydrogen leaking from each valve; collecting the hydrogen into a local pipeline through a predetermined number of branch pipelines; using a hydrogen concentration tester and an audible and visual alarm device installed in the local pipeline to monitor the hydrogen concentration and issue an alarm when the concentration exceeds the limit; installing a solenoid valve at the connection between the local pipeline and the main pipeline; controlling the opening and closing of the solenoid valve according to the hydrogen concentration in the local pipeline and the extent of exceedance; and finally, venting the hydrogen into the air through the main pipeline.

[0005] Patent 2: A method for real-time monitoring of the operating conditions of a hydrogen fuel cell vehicle, authorized announcement number CN111928908B;

[0006] The invention discloses a hydrogen fuel cell vehicle equipped with a hydrogen supply system, an air supply system, a nitrogen supply system, and a front-end PID controller; 2) it includes a rubber fastening belt and a real-time monitoring sensor unit for the cylinder's operating condition; 3) power is applied to activate the front-end PID controller and various pressure sensors, allowing the front-end PID controller to determine whether the vehicle is in a normal or abnormal operating condition; 4) when the vehicle is in an abnormal operating condition, it directly issues commands and executes corresponding operations; 5) the front-end PID controller continuously monitors and judges the vehicle's operating condition and takes corresponding actions to ensure safe operation. The invention also discloses a real-time operating condition monitoring system for hydrogen fuel cell vehicles implementing the above method. This invention can quickly and accurately determine various operating conditions, such as normal or abnormal, and monitor pressure, temperature, and hydrogen concentration in real time, avoiding false alarms and significantly improving the safety and reliability of hydrogen fuel cell vehicle operation.

[0007] Patent 3: A hydrogen redundancy monitoring and protection device and method for hydrogen-powered trams, authorized announcement number CN112895900B;

[0008] This invention provides a hydrogen redundancy monitoring and protection device and method for hydrogen-powered trams. The device includes: a hydrogen concentration sensor installed at a monitoring location in the hydrogen storage system; a first communication monitoring system that collects monitoring signals from the hydrogen concentration sensor and a second communication monitoring system; if a hydrogen leak is determined at the monitoring location based on the monitoring signals, the fault level corresponding to the monitoring signal is determined, and a fault response operation corresponding to the fault level is executed; the second communication monitoring system collects monitoring signals from the hydrogen concentration sensor and sends the monitoring signals to the first communication monitoring system; if a hydrogen leak is determined at the monitoring location based on the monitoring signals, the fault level corresponding to the monitoring signal is determined, and a fault response operation corresponding to the fault level is executed. By using at least two redundant monitoring devices, the hydrogen status is monitored in real time, and protection and alarm operations are performed, improving the safety of hydrogen energy use and preventing accidents.

[0009] The above three patents and their textual analysis are as follows: A hydrogen detector, a hydrogen sensor, and an electrochemical sensor (utilizing the chemical reaction of hydrogen), along with some auxiliary structural modifications, provide an early warning of hydrogen leaks. Catalytic and electrical hydrogen sensors can quickly and accurately respond to hydrogen concentration at room temperature and pressure, and are currently used in industry. However, these sensors based on electrical properties may generate sparks during use, potentially causing hydrogen explosions and posing a safety hazard. In contrast, fiber optic sensors detect hydrogen through sensitive materials and optical signals. They are inherently safe and unaffected by electromagnetic interference, and also possess advantages such as small size, wide measurement range, and resistance to high temperatures and pressures, attracting widespread attention and research in recent years.

[0010] Even as the above analysis shows, most hydrogen sensors exhibit cross-sensitivity to interference factors such as temperature and humidity. Both temperature and humidity affect the sensor's response signal, and some reducing gases can be absorbed by the hydrogen-sensitive material, affecting hydrogen detection. Although cross-sensitivity can be reduced through temperature and humidity compensation and surface modification of the hydrogen-sensitive material, it would be even more crucial to eliminate direct contact between hydrogen and the sensor material, thus reducing the possibility of hydrogen absorption and ensuring the accuracy of detecting leak points and amounts. This would improve the timeliness and safety of maintenance. Furthermore, if leak point misjudgment can be predicted, and the causes of leaks can be analyzed layer by layer to determine whether a leak has actually occurred, the safety and commercialization of hydrogen storage technology could be further improved. Summary of the Invention

[0011] Based on the above analysis, the purpose of this invention is to propose a non-contact sensing system and its leak detection method for hydrogen storage leak detection, in order to solve the problems that when hydrogen is in direct contact with the sensor material, the hydrogen may be absorbed by the detection material, which leads to the inability to guarantee the accuracy of the detection of hydrogen leak points and leak amounts. Furthermore, the inability to analyze the cause of the leak during the detection process results in the inability to guarantee the safety and timeliness of leak handling.

[0012] A non-contact sensing system for leak detection in hydrogen storage and its leak detection method are disclosed, comprising a hydrogen storage module, a detection module, a gas path system, and a smart terminal; the hydrogen storage module is connected through the gas path system to form a closed loop; the detection module is embedded in the hydrogen storage module and the gas path system for detecting leaks, and the detection module is electrically connected to the smart terminal;

[0013] The hydrogen storage module includes a hydrogen storage tank and a hydrogen storage chamber. The hydrogen storage chamber is used to store the hydrogen storage tank and is filled with inert gas. The hydrogen storage chamber consists of a chamber body and a door. The hydrogen storage chamber is provided with an air inlet and an air outlet. The air inlet and the air outlet are connected by a gas path system. The gas path system circulates the gas in the hydrogen storage chamber through a circulating fan and pipelines.

[0014] The detection module includes a pressure detection unit and a gas detection unit; the pressure detection unit is used to detect pressure changes at multiple locations in the hydrogen storage tank; the gas detection unit is installed on the pipeline between the circulating fan and the hydrogen storage tank, and is used to detect the gas composition during the gas circulation process.

[0015] The pressure change detected by the pressure detection unit is used to trigger the detection operation of the gas detection unit.

[0016] The hydrogen storage module, detection module, and gas path system are all electrically connected to the smart terminal to achieve intelligent integrated control.

[0017] Preferably, the hydrogen storage module further includes a bracket, a horizontal axis, and a base for auxiliary installation; the horizontal axis passes through the cabin body and the door, and the bracket supports both ends of the horizontal axis; the base is connected to the hydrogen storage chamber to cooperate with the bracket to achieve a stable support state; a clamp is installed on the horizontal axis for clamping the hydrogen storage tank; a sliding seal is installed between the door and the horizontal axis for sealing when the door slides open and closes along the axial direction of the horizontal axis.

[0018] Preferably, the hatch consists of two parts: an outer sealing part a and an inner sealing part b, wherein:

[0019] The outer sealing part a has a protrusion c; a telescopic element is installed on the outer wall of the cabin corresponding to the protrusion c, which is used to push the outer sealing part a to open the cabin door; a pressure sensor A is installed on the contact surface between the outer sealing part a and the cabin body; the inner sealing part b fits into the inner wall of the cabin body, and an annular groove for installing a sealing ring is opened on the inner sealing part b; a pressure sensor B is installed on the surface of the inner sealing part b that does not contact the inner wall of the cabin body.

[0020] Pressure sensor A and pressure sensor B are contained within the pressure detection unit; pressure sensor A is used to detect changes in pressure on the hatch when the hatch is closed; pressure sensor B is used to detect changes in pressure inside the cabin when the hatch is closed.

[0021] Preferably, the clamp consists of a connecting part, a lower clamping part, and an upper clamping part; the connecting part is used to establish a connection between the horizontal axis and the lower clamping part; one end of the lower clamping part and the upper clamping part are rotatably connected, and the other end is connected by a snap-fit ​​structure, for clamping the hydrogen storage tank; pressure sensors C are installed at the contact surfaces between the lower clamping part and the upper clamping part and the hydrogen storage tank; the pressure sensors C are also included in the pressure detection unit, and the pressure sensors C are used to detect the pressure change of the hydrogen storage tank when the hatch is closed.

[0022] Preferably, there are two doors for sealing both ends of the cabin; at least two sets of clamps are slidably installed on the horizontal axis through connecting parts, and each set of clamps is connected to the adjacent door through a pulling member, so that the hydrogen storage tank on the clamp is pulled out as the door is opened.

[0023] Preferably, the connecting part includes a bushing a and a connecting rod b; the bushing a is sleeved on the horizontal axis, and the multiple connecting rods b connected on the bushing a can both rotate around the horizontal axis and slide along the axial direction; the connecting rod b is provided with an installation part for detachable connection with the pulling member; the end of the pulling member located on the hatch is also provided with a detachable connection structure.

[0024] Preferably, the air path system further includes a guide fan and an air box; the air box is used to install the guide fan and the circulating fan, and the space where the guide fan and the circulating fan are located in the air box is isolated from each other to form an independent space that does not interfere with each other;

[0025] The air box is connected to at least five pipes that run through the interior. Four of these pipes are used to ensure that the airflow can flow in the air box where the guide fan and the circulating fan are located, respectively. The two pipes on the same side are connected to the pipes that connect to the air inlet and air outlet of the hydrogen storage chamber through a T-joint. The other at least one pipe is connected to an external gas storage unit for supplying the required gas to the hydrogen storage chamber from the outside or supplying gas to the outside.

[0026] Electrically controlled valves are installed in the pipes on both sides of the air box where the circulating fan and the guide fan are located.

[0027] Preferably, the gas detection unit includes a gas sensor array, an A / D converter, a microcontroller, and a data cable;

[0028] The gas sensor array is composed of several individual gas sensors and is fabricated using an integrated process. The gas sensors are used to detect specific components in the gas and convert them into electrical signals. The integration facilitates centralized acquisition and processing of the signals.

[0029] In this process, after the gas flows through the gas sensor array, the weak electrical signal output by the gas sensor array is preprocessed by its respective signal amplification circuit to convert it into a DC signal that varies within the range of 0-5V. This DC signal is then sent to the A / D conversion circuit to be converted into a digital signal for data acquisition and processing.

[0030] The microcontroller mainly processes the collected data, calculates the concentration of various gases according to mathematical models, and displays the corresponding gas type and concentration value on a digital tube. When the concentration exceeds the standard, an alarm is triggered by the intelligent terminal.

[0031] Preferably, when the system detects and determines whether a leak has occurred, it should first detect changes in the pressure on the hatch when the hatch is closed using pressure sensor A, and then the intelligent terminal should synchronously monitor whether there are changes in the internal pressure value of pressure sensor B within a certain period of time.

[0032] If no change in the value of pressure sensor B is found, it is determined that the hatch is under external pressure. If the pressure change continues for more than 30 seconds, the smart terminal needs to issue a relevant reminder so that maintenance personnel can determine in time whether on-site inspection is required.

[0033] If a change in the value of pressure sensor B is detected and reaches the set threshold, it is determined that the cabin is under external pressure or there is an internal leak.

[0034] Preferably, when a judgment is made based on the change in pressure sensor B that the cabin is under external pressure or that there is an internal leak, the intelligent terminal then monitors whether there is a change in pressure value in pressure sensor C:

[0035] If there is no pressure change in pressure sensor C, it is determined that the door is not leaking due to external pressure. At this time, if the pressure change detected by pressure sensor B continues to exceed the set time, the smart terminal will issue a relevant reminder to remind maintenance personnel to go to the site for inspection.

[0036] If the pressure sensor C shows a pressure change and reaches the set threshold, it is preliminarily determined that the gas storage tank is leaking; at this time, the smart terminal turns on the circulating fan, so that the gas in the hydrogen storage tank flows out and is detected by the gas detection unit during the flow in the pipeline.

[0037] If the gas detection unit detects no hydrogen in the gas composition at this time, it is determined that the gas inside the chamber is subjected to a chain reaction caused by excessive external pressure. The pressure detection threshold is adjusted to adapt to the detection misjudgment caused by the external environment. If necessary, maintenance personnel are dispatched to the site for inspection.

[0038] If the gas detection unit detects the presence of hydrogen in the gas composition, it determines that there is a leak, opens the electrically controlled valves in the pipes on both sides of the guide fan, introduces inert gas from the outside for dilution and protection, and promptly dispatches maintenance personnel to the site for repair.

[0039] The beneficial effects of this invention are as follows:

[0040] (1) This invention uses a pressure detection unit to detect pressure changes at multiple locations in the hydrogen storage module. After the collected detection data is analyzed by a smart terminal, it is determined whether to use a gas detection module to analyze the composition. This ensures accurate detection of problems while reducing the inefficiency and untimely discovery of problems caused by general global detection in the prior art. When the gas detection unit needs to be involved in analyzing the gas composition, it usually means that there may be a leak. This leak may be a leak in the hydrogen storage tank seal or a leak in the hydrogen storage tank. Therefore, the pressure detection unit and the gas detection unit can effectively complete the efficient composition analysis. Under the action of the circulating gas in the gas path system, the composition data is accurate, thereby judging that there is a dangerous state at the problem point and dispatching relevant maintenance personnel to the site for repair in a timely manner. If the amount of leaked hydrogen is too large and the concentration in the closed hydrogen storage tank is too high, the concentration at the local location during the leak is diluted by the gas circulation of the gas path system or by introducing new protective gas from the outside, reducing the rate of danger and buying time for personnel to safely carry out emergency repairs.

[0041] (2) Under the unified control of the smart terminal, when the outer seal of the hatch and the cabin body are in closed contact, the initial pressure value set by the pressure sensor A is determined, which facilitates accurate monitoring of the pressure value that may change in the future; at the same time, after the hatch and the cabin body are closed, after a fixed amount of protective gas is filled into the cabin body, the initial pressure value of the pressure sensor B on the inner seal of the hatch is set without the premise of sealing leakage, which facilitates accurate monitoring of the pressure value that may change in the future, as well as the accuracy of the linkage detection of pressure sensor A and pressure sensor B and the analysis and judgment by the smart terminal.

[0042] (3) When detecting and determining whether a leak has occurred, the present invention should first detect the change in pressure on the hatch under the closed state as sensed by pressure sensor A, and then the intelligent terminal should detect whether there is a change in the internal pressure value of pressure sensor B: if no change in pressure sensor B is found, it is determined that the hatch is under external pressure. If the pressure change lasts for more than 30 seconds, the intelligent terminal needs to issue a relevant reminder so that maintenance personnel can determine whether on-site inspection is required in a timely manner; if a change in pressure sensor B is found and reaches the set threshold, it is determined that the cabin is under external pressure or there is a leak inside; it should be noted that if the local air pressure changes due to the external environment, the intelligent terminal will adjust the detection threshold of the pressure sensor according to the actual situation after determining that there is no danger, so as to ensure that frequent misjudgments are not caused.

[0043] (4) The accurate leak detection of this invention corresponds to the change in detection requirements and judgment order. That is, the normal order is to continue to detect the pressure change by pressure sensor B and the pressure reaches the set threshold, then it is determined that the cabin is under external pressure or there is a leak inside. At this time, the intelligent terminal monitors whether there is a pressure change by pressure sensor C:

[0044] If there is no pressure change in pressure sensor C, it is determined that the door is not leaking due to external pressure. If the pressure change detected by pressure sensor B continues to exceed the set time, the smart terminal will issue a relevant reminder to remind maintenance personnel to go to the site for inspection.

[0045] If the pressure sensor C shows a pressure change and reaches the set threshold, it is preliminarily determined that the gas storage tank is leaking; at this time, the smart terminal turns on the circulating fan, so that the gas in the hydrogen storage tank flows out and is detected by the gas detection unit during the flow in the pipeline.

[0046] If the gas detection unit detects no hydrogen in the gas composition at this time, it is determined that the gas inside the cabin is affected by external factors, causing a chain reaction, and the maintenance personnel are reminded to go to the site for inspection.

[0047] If the gas detection unit detects the presence of hydrogen in the gas composition at this time, it determines that there is a leak, immediately closes the electrically controlled valves in the pipes on both sides of the circulating fan, and opens the electrically controlled valves in the pipes on both sides of the guide fan to introduce inert gas from the outside for dilution and protection. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 This is a basic flowchart of the sensing system of the present invention;

[0050] Figure 2 This is a schematic diagram of the hydrogen storage module of the present invention;

[0051] Figure 3 for Figure 2 Sectional view at point AA;

[0052] Figure 4 for Figure 2 Enlarged view of a portion of point B in the middle;

[0053] Figure 5 for Figure 2 Partial view at point C;

[0054] Figure 6 A schematic diagram showing the installation of the hatch and related components;

[0055] Figure 7 A schematic diagram of the connection between the gas detection unit's A / D converter and the microcontroller;

[0056] Figure 8 The following is the process flow of the leak detection method of the present invention. Figure 1 ;

[0057] Figure 9 The following is the process flow of the leak detection method of the present invention. Figure 2 .

[0058] The components in the diagram are labeled as follows: hydrogen storage module 1, hydrogen storage tank 11, hydrogen storage chamber 12, chamber body 121, door 122, outer seal 122a, inner seal 122b, protrusion 122c, air inlet 123, air outlet 124, bracket 13, horizontal axis 14, base 15, gas path system 2, circulating fan 21, guide fan 22, air box 23, pressure detection unit 3, pressure sensor A31, pressure sensor B32, pressure sensor C33, gas detection unit 4, clamp 5, connecting part 51, bushing 51a, connecting rod 51b, lower clamping part 52, upper clamping part 53, and pulling component 6. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0060] This invention addresses the problems in existing hydrogen storage systems where hydrogen comes into direct contact with sensor materials, potentially leading to hydrogen absorption and consequently compromising the accuracy of leak detection. Furthermore, the inability to accurately diagnose leaks during detection compromises the safety and timeliness of leak management. These issues directly impact the adaptability of hydrogen storage systems to diverse external storage environments, easily causing a series of related problems. Specifically, when multiple hydrogen storage tanks are concentrated, the accuracy of detection may be affected by the external environment, influencing the determination of whether a leak is due to hydrogen storage. If the cause of an anomaly cannot be determined through the detection system, the timeliness of subsequent troubleshooting and repair cannot be guaranteed, and the safety of on-site repair personnel cannot be assured.

[0061] To address this, the following embodiments are used to illustrate the detailed process by which this system solves the existing problems;

[0062] Regarding Example 1, please refer to the appendix to the specification. Figure 1-2 As shown, the solution to the problem in this application mainly relies on four major components: hydrogen storage module 1, detection module, gas path system 2, and intelligent terminal. By designing the relevant structures and information transmission of each of the four components, a chain effect of accurate judgment, efficient detection, composition and hazard analysis, and safety maintenance can be achieved.

[0063] Specifically, the present invention stores several hydrogen storage tanks 11 in a hydrogen storage chamber 12, and fills the hydrogen storage chamber 12 with protective gas through an air inlet 123 provided on the hydrogen storage chamber 12. The protective gas is preferably an inert gas. However, considering that there may be multiple gases in the protective gas that may cause danger with the leaked hydrogen in a specific external environment, we choose one of them, namely an inert gas, to fill the chamber. At the same time, we ensure that even if a hydrogen leak occurs, the probability of danger will be reduced due to the protection of the inert gas.

[0064] In addition, the pressure detection unit 3 in the detection module detects pressure changes at multiple locations in the hydrogen storage module 1. After the intelligent terminal analyzes the collected detection data, it determines whether to use the gas detection module 3 to analyze the composition. This ensures accurate detection of problems while reducing the inefficiency and untimely problem detection caused by the general global detection in the existing technology. When the gas detection unit 4 needs to be involved in analyzing the gas composition, it usually means that a leak may have occurred. This leak may be a leak in the seal of the hydrogen storage chamber 12 or a leak in the hydrogen storage tank 11 stored in the hydrogen storage chamber 12. Therefore, the pressure detection unit 3 and the gas detection unit 4 can effectively complete the efficient composition analysis. Under the action of the circulating gas in the chamber of the gas path system 2, the composition data is ensured to determine whether there is a dangerous situation at the problem point, and relevant maintenance personnel can be dispatched to the site for repair in a timely manner. If the amount of leaked hydrogen is too large and the concentration in the closed hydrogen storage chamber 12 is too high, the concentration at the local location can be diluted by the gas circulation of the gas path system 2 or by introducing new protective gas from the outside, reducing the rate of danger and buying time for personnel to carry out emergency repairs.

[0065] Here, through Example 2, refer to the appendix. Figure 2 , 3 6 and appendix Figure 8-9 The following is a detailed explanation of the operation process and principle of this system. The difference between this implementation and the first implementation is that the pressure detection unit 3 and the hydrogen storage module 1 are used in combination in a specific structural design.

[0066] Considering the possible environments in which this system may be used, such as heat, water pressure fluctuations, and frequent changes in high-altitude climate, we have disassembled the hydrogen storage module 1 into multiple independent parts that are easy to assemble and install, and designed the door opening and the storage method of the hydrogen storage tank 11 to avoid the problem that storage in different environments may cause interference to the detection.

[0067] In this study, we used the most common land-based plant area as the storage environment, with cleanliness, dust-free conditions, constant temperature and pressure, and a ban on smoking as storage conditions. The horizontal axis 14 was mounted on the bracket 13, and the hydrogen storage tank 11 was coaxially mounted on the base 15 with the horizontal axis 14. The horizontal axis 14 penetrates the hydrogen storage tank 11, ensuring that the hatch 122 is sealed and slidably mounted on the horizontal axis 14. A pressure sensor A31 was installed on the contact surface between the outer sealing part 122a of the hatch 122 and the cabin body 121, and a pressure sensor B32 was also installed on the inner sealing part 122b of the hatch 122, which does not contact the inner wall of the cabin body 121. Pressure sensor A31 is used to detect pressure changes in the hatch 122 when it is closed; pressure sensor B32 is used to detect pressure changes inside the cabin body 121 when the hatch 122 is closed.

[0068] In order to ensure the fitting tightness and uniform stress between the cabin door 122 and the cabin body 121, in the present invention, a protruding portion 122c is additionally provided on the outer sealing portion 122a, and a telescopic element is installed at a position on the outer wall of the cabin body 121 corresponding to the protruding portion 122c. The telescopic element is configured to push the outer sealing portion 122a to open the cabin door 122. The telescopic element can adopt an electrically controlled component such as an electric cylinder, so as to be electrically connected with an intelligent terminal and realize automatic remote control of the opening and closing of the cabin door 122. Furthermore, a plurality of telescopic elements can be uniformly arranged along the outside of the cabin body 122 (four is preferable). Under the unified control of the intelligent terminal, when the outer sealing portion 122a of the cabin door 122 is in closed contact with the cabin body 121, the initial pressure value set by the pressure sensor A31 can be determined, which facilitates accurate monitoring of pressure values that may change subsequently; meanwhile, after the cabin door 122 is closed with the cabin body 121 and a fixed amount of protective gas is filled into the cabin body 121, on the premise of no sealing leakage, the initial pressure value of the pressure sensor B32 on the inner sealing portion 122b of the cabin door 122 is set, which facilitates accurate monitoring of pressure values that may change subsequently, and improves the accuracy of linkage detection of the pressure sensor A31 and the pressure sensor B32 and analysis and judgment by the intelligent terminal; wherein the telescopic element, the pressure sensor A31 and the pressure sensor B are all electrically connected with the intelligent terminal to realize intelligent control;

[0069] Further, when the system detects and determines whether leakage occurs, it shall first obtain the pressure change of the cabin door 122 in the closed state sensed by the pressure sensor A31, and then the intelligent terminal detects whether there is a change in the cabin pressure value of the pressure sensor B32:

[0070] If it is found that there is no numerical change of the pressure sensor B32, it is determined that the cabin door 122 is subjected to external pressure. If the pressure change lasts for more than 30S, the intelligent terminal needs to send a relevant reminder, so that maintenance personnel can timely determine whether on-site inspection is required;

[0071] If it is found that there is a numerical change of the pressure sensor B32 and the change reaches the set threshold, it is determined that the cabin body 121 is subjected to external pressure or internal leakage occurs.

[0072] It should be noted that if the local air pressure change is caused by the external environment, the intelligent terminal will adjust the detection threshold of the pressure sensor according to the actual situation after judging that there is no danger, so as to avoid frequent false judgments.

[0073] However, considering that the probability of pressure changes caused by external factors to pressure sensor A31 and pressure sensor B32 is greater than that caused by internal factors, we install a pressure sensor C33 close to the hydrogen storage tank 11, and the pressure sensor C33 is electrically connected with the intelligent terminal to facilitate intelligent control;

[0074] For pressure sensor C33, the optimal position is where the lower clamping part 52 and the upper clamping part 53 of clamp 5 contact the hydrogen storage tank 11. This is because pressure sensor C33 directly captures the expansion and contraction changes of the hydrogen storage tank 11 after inflation or depressurization, allowing for more accurate judgment of whether a leak in the hydrogen storage tank 11 has caused a change in constant pressure. Thus, accurate leak detection corresponds to a change in detection requirements and judgment sequence. The normal sequence is that if pressure sensor B32 detects a pressure change that reaches a set threshold, it is determined that the chamber 121 is under external pressure or has an internal leak. At this point, the intelligent terminal monitors whether pressure sensor C33 shows a change in pressure value.

[0075] If there is no pressure change in pressure sensor C33, it is determined that the external pressure on hatch 122 is not causing a leak. If the pressure change detected by pressure sensor B32 continues to exceed the set time (30 seconds), the smart terminal will issue a relevant reminder to remind maintenance personnel to go to the site for inspection.

[0076] If the pressure sensor C33 shows a pressure change and reaches the set threshold, it is preliminarily determined that the gas storage tank is leaking; at this time, the smart terminal turns on the circulating fan 21, so that the gas in the hydrogen storage chamber 12 flows out and is detected by the gas detection unit 4 during the flow in the pipeline.

[0077] If the gas detection unit 4 detects no hydrogen in the gas composition at this time, it is determined that the gas in the cabin is affected by external factors, causing a chain reaction, and the maintenance personnel are reminded to go to the site for inspection.

[0078] If the gas detection unit 4 detects hydrogen in the gas composition at this time, it determines that there is a leak, immediately closes the electrically controlled valves in the pipes on both sides of the circulating fan 21, and opens the electrically controlled valves in the pipes on both sides of the guide fan 22 to introduce inert gas from the outside for dilution and protection.

[0079] However, it should be noted that the pressure detection of pressure sensor C33 exists both independently and in conjunction with other sensors; that is, in addition to the detection sequence mentioned above, it can also achieve:

[0080] When a pressure change is detected in pressure sensor C33, based on the initial condition that the gas pressure in hydrogen storage chamber 12 is lower than that in hydrogen storage tank 11, it can be known that if a leak occurs, the detected value of pressure sensor C33 should decrease, while the pressure value detected by pressure sensor B32 should increase, with the values ​​gradually approaching each other. However, if it is a chain reaction caused by external factors, the pressure changes detected by pressure sensor C33 and pressure sensor B32 will rise synchronously. Therefore, the influence of external or internal factors on the judgment of whether a leak has occurred is effectively distinguished when hydrogen storage tank 11 is located in different storage environments, thus achieving more accurate cause detection. This greatly improves risk reduction, risk management efficiency, and personnel safety.

[0081] Here, through Example 3, refer to Appendix Figure 3-5 As shown, the operation process and principle of this system are explained in detail. The difference between this implementation and the above-mentioned implementation 2 is that the opening and closing door design of the hydrogen storage tank 12 further ensures the detection accuracy and also ensures the safety of personnel during maintenance.

[0082] By designing the hydrogen storage chamber 12 as a structure that runs through both ends and equipping it with two doors 122, the telescopic element responsible for opening the doors 122 is independently controlled on one side, reducing the possibility of the unified control failing to open in case of a malfunction. In addition, since the doors 122 on both sides and the pressure sensors A31 and B32 arranged on them are the same, the doors 122 are opened and closed by reciprocating movement on the horizontal axis 14, ensuring that pressure changes can be detected in a timely manner on either side. This is because the hydrogen storage tanks 11 stored in the hydrogen storage chamber 12 will be numerous, and the timeliness of leak point confirmation directly affects the safety of equipment use and maintenance personnel.

[0083] However, in addition to the above functions, in order to achieve safe maintenance and convenient installation of hydrogen storage tank 11, when the hatch is opened, the clamp 5 is slid out along the horizontal axis 14 by the pulling component 6, so as to avoid personnel entering the hydrogen storage tank 12 for maintenance or installation.

[0084] In this design, the clamp 5 only needs to meet the following requirements: it rotates on the horizontal axis 14 in a Ferris wheel shape to easily clamp multiple hydrogen storage tanks 11; the clamp 5 can be pulled out along the horizontal axis 14 as the hatch opens; and the clamp 5 can be opened to disassemble the hydrogen storage tanks 12 for maintenance and replacement. Therefore, the clamp 5 is composed of a connecting part 51, a lower clamping part 52, and an upper clamping part 53 connected in sequence. The connecting part 51 can adopt a bushing 51a and a connecting rod 51b structure. The bushing 51a is sleeved on the horizontal axis 14. However, the bushing 51a can rotate around the axis of the horizontal axis 14 and... It can slide along the axial direction. After the bushing 51a is fixedly connected to the connecting rod 51b, the hydrogen storage tank 11 held by the lower clamping part 52 and the upper clamping part 53 on the connecting rod 51b can also rotate and slide accordingly. In order to ensure the realization of the function, the supporting structural parts are simple and easy to manufacture. Our lower clamping part 52 and upper clamping part 53 are simple two-half-circular arc splicing structures for tank clamping. One side of the two half-circular arcs is rotatably connected, and the other end is connected by a buckle. For details, please refer to the figure. The corresponding pressure sensor C33 is arranged on the surface of the lower clamping part 52 and the upper clamping part 53 in contact with the hydrogen storage tank 11.

[0085] For the pulling component 6, in order for the clamps 5 to be pulled out as the hatch opens, to disengage from each other after being pulled out, and to be pushed back synchronously after being pulled out, this solution specifically provides mounting holes (through holes) on the mounting location of the connecting rod 51b of the clamps 5. Two pin holes are provided through the pulling component 6 at the end furthest from the adjacent hatch 122. After the pulling component 6 passes through the mounting holes on the connecting rod 51b, the two pin holes are located on both sides of the connecting rod 51b. Limiting pins are installed in the pin holes to limit the left and right movement of the pulling component 6 relative to the connecting rod 51b, thereby enabling the clamps 5 to be pulled out as the hatch opens and to be pushed back synchronously after being pulled out. Disengagement after being pulled out can also be achieved, but it should be noted that disengagement after being pulled out means that when the hatch can only... Opening to a certain range means that the extension distance at both ends of the horizontal axis is too long, which is not conducive to ensuring the stability of the installation. Not detaching effectively ensures the stability of the clamp 5 and the hydrogen storage tank 11 placed in the hydrogen storage chamber 12. Detachment is considered because the clamp 5 needs to be rotated to install multiple hydrogen storage tanks 11. Therefore, the detachable connection structure set at one end of the pulling member 6 on the hatch 12 can refer to the above-mentioned pin connection method. Thus, an additional mounting seat is added to the hatch 122, and pin holes are inserted at corresponding positions on the mounting seat and the pulling member 6, and then a detachable connection is made with pins. The above connection method is one of the simplest and most practical methods for the required function, but this solution is not limited to protecting only the above-mentioned installation method.

[0086] When maintenance personnel need to rotate the clamp for maintenance or replacement of the hydrogen storage tank 11, they can remove one end of the pulling member 6 from the hatch 122, then remove the pin at the other end of the pulling member 6 near the hatch 122, slide the pulling member 6 along the mounting hole for one distance, and use the pulling member 6 as an arm to pry the clamp 5, thereby assisting in rotating the hydrogen storage tank 11 and improving the convenience of maintenance and replacement.

[0087] Example 4 provides further details; please refer to the appendix. Figure 1 , 8 As shown in Figure 9, to ensure the smooth implementation of the entire detection system, Example 1 indicates that during the detection process, the circulating fan 21 promotes continuous circulation of gas within the hydrogen storage chamber 12 and the pipeline system. This ensures that even if a leak occurs, the leaked hydrogen can be quickly dispersed in a short time, preventing danger caused by hydrogen leakage and concentration in one place. At the same time, when the fully mixed gas flows through the gas detection unit 4, the gas detection unit 4 can more accurately analyze the composition of the circulating gas. By combining the detection results of the pressure detection unit 3, a comprehensive analysis can be conducted to determine whether a leak has occurred and the specific location of the leak, thereby quickly providing a response.

[0088] However, compared to Embodiment 1, Embodiment 4, by adding a diversion fan 22, can prevent the danger caused by an increase in the concentration of hydrogen in the sealed chamber 12 due to hydrogen leakage by diluting the hydrogen content in the pipeline and hydrogen storage chamber 12 in advance before a leak is confirmed, especially when the pressure sensor C33 has detected a relevant pressure change. Therefore, even if a leak does occur, the probability of danger in a short period of time is greatly reduced, extending the time for safe repair and ensuring the safety of maintenance personnel.

[0089] If no leak is found during testing, the gas in the hydrogen storage chamber 12 is recovered by the flow guide fan 22 to ensure that the gas pressure in the hydrogen storage chamber 12 returns to the required range, and to ensure the continuous and stable progress of subsequent testing work. The flow guide fan 22 has a pressurization function.

[0090] When the guide fan 22 or the circulating fan is not triggered, all electrically controlled valves installed in the pipeline are closed, meaning they are only opened when it is necessary to adjust the air pressure inside the chamber or to play a dilution protection role.

[0091] Considering that in special circumstances, improper management of aging equipment can easily lead to large leaks, and when the leak is determined to be large according to the aforementioned detection method, when the flow guide fan 22 or the circulating fan is triggered to work, the two side doors will also be opened simultaneously. The inert gas that is pressurized and rushed into the flow guide fan 22 has the characteristic of high-speed flow, so that the hydrogen gas can be quickly dispersed into the external environment with the airflow, thereby reducing the probability of danger caused by hydrogen concentration. Among them, the flow guide fan 22, the circulating fan and the electromechanical control valve are all electrically connected to the intelligent terminal, which facilitates remote intelligent control.

[0092] Example 5, see attached document Figure 7 As shown, the gas detection unit 4 includes a gas sensor array, an A / D converter, a microcontroller, and a data cable;

[0093] The gas sensor array is composed of several individual gas sensors and is fabricated using an integrated process. The gas sensors are used to detect specific components in the gas and convert them into electrical signals. The integration facilitates centralized acquisition and processing of the signals.

[0094] In this process, after the gas flows through the gas sensor array, the weak electrical signal output by the gas sensor array is preprocessed by its respective signal amplification circuit to convert it into a DC signal that varies within the range of 0-5V. This DC signal is then sent to the A / D conversion circuit to be converted into a digital signal for data acquisition and processing.

[0095] The microcontroller mainly processes the collected data, calculates the concentration of various gases according to mathematical models, and displays the corresponding gas type and concentration value on the digital tube. When the concentration exceeds the standard, the intelligent terminal will issue an alarm.

[0096] A single gas sensor differs qualitatively from the sensor arrays used in existing technologies. The response of a single gas sensor to an odor / gas can be represented by intensity, while a gas sensor array, in addition to the response of each individual sensor, forms a response pattern in a multi-dimensional space composed of all sensors. Under certain environmental conditions, the response pattern on the array corresponds one-to-one with its excitation, which is the key to the system's ability to identify a variety of odors and gases.

[0097] This design collects gas information through a gas sensor array, converts the collected information into electrical signals, and then sends them to an A / D converter for analog-to-digital conversion.

[0098] The data acquisition and data processing system includes:

[0099] The weak electrical signals output by the gas sensor array are preprocessed by their respective signal amplification circuits to convert them into DC signals that vary within the range of 0-5V. These signals are then sent to the A / D conversion circuit to be converted into digital signals for data acquisition and processing.

[0100] To facilitate connection with the microcontroller, this system uses an A / D converter chip to perform analog-to-digital conversion on the acquired gas information. It has an 8-bit resolution, eliminates the need for zero-point and full-scale adjustments, and features a high-impedance chopper-stabilized comparator. An 8-channel multiplexer can directly access one of eight single-ended analog signals. The microcontroller initiates the A / D converter, and after conversion, the converter sends an interrupt request signal, which the CPU responds to. The conversion result is read from the decoder and sent to the corresponding storage area of ​​the measured quantity. The measured quantity is then reselected, and the A / D conversion is restarted, after which the interrupt returns. The wiring between the A / D converter and the microcontroller is shown in the attached manual. Figure 7 As shown.

[0101] In this system, the microcontroller mainly processes the collected data, calculates the concentration of various gases according to mathematical models (existing technology), and displays the corresponding gas type and concentration value on a digital tube. When the concentration exceeds the standard, an alarm is triggered.

[0102] The system also employs a frequency divider; the frequency divider divides the pulse signal by a power of 2 (1 / 2^n), for example, converting a 32768Hz pulse signal into a 1Hz second signal. This is typically implemented using T flip-flops; the flip-flop state changes after each pulse, and after processing by n T flip-flops, the 1 / 2^n divided signal is obtained. The microcontroller is connected to a 12MHz crystal oscillator, and after passing through the ALE pin, the output is sent to the frequency divider to obtain a 2MHz signal. The frequency divider then provides the necessary operating clock for the A / D converter.

Claims

1. A non-contact sensing system for detecting leaks in hydrogen storage, comprising a hydrogen storage module (1), a detection module, a gas path system (2), and a smart terminal; wherein the hydrogen storage module (1) is connected to the gas path system (2) to form a closed loop; the detection module is embedded in the hydrogen storage module (1) and the gas path system (2) for detecting leaks, and the detection module is electrically connected to the smart terminal, characterized in that: The hydrogen storage module (1) includes a hydrogen storage tank (11) and a hydrogen storage chamber (12); the hydrogen storage chamber (12) is used to store the hydrogen storage tank (11), and the hydrogen storage chamber (12) is filled with inert gas. The hydrogen storage chamber (12) consists of a chamber body (121) and a door (122); the hydrogen storage chamber (12) is provided with an air inlet (123) and an air outlet (124); the air inlet (123) and the air outlet (124) are connected by a gas path system (2); the gas path system (2) circulates the gas in the hydrogen storage chamber (12) through a circulating fan (21) and pipelines included therein; The detection module includes a pressure detection unit (3) and a gas detection unit (4); the pressure detection unit (3) is used to detect pressure changes at multiple locations in the hydrogen storage tank (12); the gas detection unit (4) is installed on the pipeline between the circulating fan (21) and the hydrogen storage tank (12), and the gas detection unit (4) is used to detect the gas composition during the gas circulation process; The pressure change detected by the pressure detection unit (3) is used to trigger the detection work of the gas detection unit (4); The hydrogen storage module (1) also includes a bracket (13), a horizontal shaft (14), and a base (15) for auxiliary installation; the horizontal shaft (14) passes through the cabin body (121) and the hatch (122), and the bracket (13) supports both ends of the horizontal shaft (14); the base (15) is connected to the hydrogen storage tank (12) to cooperate with the bracket (13) to achieve a stable support state; a clamp (5) is installed on the horizontal shaft (14), which is used to clamp the hydrogen storage tank (11); the hatch (122) consists of an outer sealing part (122a) and an inner sealing part (122b), wherein: The outer sealing part (122a) is provided with a protrusion (122c); a telescopic element is installed on the outer wall of the cabin (121) at the position corresponding to the protrusion (122c), the telescopic element is used to push the outer sealing part (122a) to open the cabin door (122); a pressure sensor A (31) is installed on the contact surface between the outer sealing part (122a) and the cabin (121); a pressure sensor B (32) is provided on the surface of the inner sealing part (122b) that does not contact the inner wall of the cabin (121). The pressure sensor A (31) and pressure sensor B (32) are contained in the pressure detection unit (3); the pressure sensor A (31) is used to detect the pressure change of the hatch (122) when the hatch (122) is closed; the pressure sensor B (32) is used to detect the pressure change inside the cabin (121) when the hatch (122) is closed. The clamp (5) consists of a connecting part (51), a lower clamping part (52) and an upper clamping part (53); the connecting part (51) is used to establish a connection between the horizontal axis (14) and the lower clamping part (52); the lower clamping part (52) and the upper clamping part (53) are rotatably connected at one end and connected by a snap-fit ​​structure at the other end, and are used to clamp the hydrogen storage tank (11); pressure sensors C (33) are installed at the contact surfaces of the lower clamping part (52) and the upper clamping part (53) with the hydrogen storage tank (11); the pressure sensor C (33) is also included in the pressure detection unit (3), and the pressure sensor C (33) is used to detect the pressure change of the hydrogen storage tank (11) when the hatch (122) is closed.

2. The non-contact sensing system for hydrogen storage leak detection according to claim 1, characterized in that: Two doors (122) are provided for sealing both ends of the cabin body (1 (21)); at least two sets of clamps (5) are slidably installed on the horizontal axis (14) through the connecting part (51). Each set of clamps (5) is connected to the adjacent door (122) through the pulling part (6) so that the hydrogen storage tank (11) on the clamp (5) can be pulled out when the door (122) is opened.

3. The non-contact sensing system for hydrogen storage leak detection according to claim 2, characterized in that: The connecting part (51) includes a bushing (51a) and a connecting rod (51b); the bushing (51a) is sleeved on the horizontal shaft (14) so ​​that the multiple connecting rods (51b) connected on the bushing (51a) can both rotate around the axis of the horizontal shaft (14) and slide along the axial direction; the connecting rod (51b) is provided with an installation part for detachable connection with the traction member (6); the end of the traction member (6) located on the hatch (122) is also provided with a detachable connection structure.

4. The non-contact sensing system for hydrogen storage leak detection according to claim 1, characterized in that: The air path system (2) also includes a guide fan (22) and a wind box (23); the wind box (23) is used to install the guide fan (22) and the circulating fan (21), and the space where the guide fan (22) and the circulating fan (21) are located in the wind box (23) is isolated from each other into independent spaces that do not interfere with each other; The air box (23) is connected to at least five pipes that run through the interior. Four of these pipes are used to ensure that the airflow can flow in the air box (23) where the guide fan (22) and the circulating fan (21) are located, respectively. The two pipes on the same side are connected to the pipes that connect from the air inlet (123) and air outlet (124) on the hydrogen storage chamber (12) through a T-joint. The other at least one pipe is connected to an external gas storage unit for supplying the required gas to the hydrogen storage chamber (12) from the outside or supplying gas to the outside. Electrically controlled valves are installed in the pipes on both sides of the air box (23) where the circulating fan (21) and the guide fan (22) are located.

5. A non-contact sensing system for detecting leaks in hydrogen storage according to claim 1, characterized in that: The gas detection unit (4) includes a gas sensor array, an A / D converter, a microcontroller, and a data cable; The gas sensor array is composed of several individual gas sensors and is fabricated using an integrated process. The gas sensors are used to detect the components to be detected in the gas and convert them into electrical signals. The integration facilitates centralized acquisition and processing of the signals. In this process, after the gas flows through the gas sensor array, the weak electrical signal output by the gas sensor array is preprocessed by its respective signal amplification circuit to convert it into a DC signal that varies within the range of 0-5V. This DC signal is then sent to the A / D conversion circuit to be converted into a digital signal for data acquisition and processing. The microcontroller mainly processes the collected data, calculates the concentration of various gases according to mathematical models, and displays the corresponding gas type and concentration value on a digital tube. When the concentration exceeds the standard, an alarm is triggered by the intelligent terminal.

6. A leak detection method for a sensing system according to any one of claims 1-5, characterized in that: When using the aforementioned system to detect and determine whether a hydrogen leak has occurred, the system first detects changes in the pressure on the hatch (122) when it is closed, based on pressure sensor A (31). Then, the intelligent terminal synchronously monitors whether there are changes in the internal pressure value of pressure sensor B (32) within a certain period of time. If no change in the value of pressure sensor B (32) is found, it is determined that the hatch (122) is under external pressure; and if the pressure change lasts for more than 30 seconds, the smart terminal needs to issue a relevant reminder and dispatch maintenance personnel to conduct on-site inspection. If a change in the value of pressure sensor B (32) is detected and reaches the set threshold, it is determined that the cabin (121) is subjected to external pressure or that there is an internal leak.

7. A leak detection method according to claim 6, characterized in that: When a judgment is made based on the change value of pressure sensor B (32) that the cabin (121) is affected by external pressure or that there is an internal leak, the intelligent terminal then monitors whether there is a change in the pressure value of pressure sensor C (33): If there is no pressure change in pressure sensor C (33), it is determined that the door (122) is not leaking due to external pressure; at this time, if the pressure change detected by pressure sensor B (32) continues to exceed the set time, the smart terminal will issue a relevant reminder to remind maintenance personnel to go to the site for inspection. If the pressure sensor C (33) shows a pressure change and reaches the set threshold, it is preliminarily determined that the gas storage tank has leaked; at this time, the smart terminal turns on the circulating fan (21) so that the gas in the hydrogen storage chamber (12) flows out and is detected by the gas detection unit (4) during the process of flowing in the pipeline. If the gas detection unit (4) detects no hydrogen in the gas composition at this time, it is determined that the gas in the cabin is subjected to excessive external pressure, which is a chain reaction. The pressure detection threshold is adjusted to adapt to the detection misjudgment caused by the external environment. Maintenance personnel can be dispatched to the site for inspection. If the gas detection unit (4) detects hydrogen in the gas component at this time, it determines that there is a leak, opens the electrically controlled valves in the pipes on both sides of the guide fan (22), introduces inert gas from the outside to dilute and protect it, and promptly dispatches maintenance personnel to the site for maintenance.

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