Micro-leakage and micro-damage monitoring system and method for hydrogen storage bottle group of hydrogen refueling station

Abstract

The hydrogen storage bottle group micro-leakage and micro-damage monitoring system and method belong to the hydrogen energy safety monitoring field, and aim to solve the problems of passive alarm, response lag, inability to identify bottle micro-damage and micro-leakage, large environmental interference, high false and missed alarm rates, and difficulty in early warning in the existing combustible gas probe manual inspection mode. The high-precision pressure transmitter, high-resolution temperature sensor, valve state detection module and central controller are added, the original equipment is compatible to build a double-redundancy architecture, the valve signal linkage is used to determine the closed static state, the pressure-temperature ratio dynamic deviation analysis is used, the temperature compensation and data filtering are combined, the hidden danger grading early warning and fault interlocking isolation are realized. The present application can accurately capture the early micro-leakage, material fatigue and micro-crack hidden defects of the hydrogen storage bottle group, has strong environmental interference resistance, can actively warn several hours to several days in advance, prolongs the service life of the equipment, outputs traceable quantitative data, supports the safety compliance and fine risk control of the hydrogen refueling station.

Description

Technical Field

[0001] This invention relates to the field of hydrogen energy safety monitoring technology, and in particular to a system and method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations. Background Technology

[0002] Hydrogen refueling stations are critical infrastructure for hydrogen energy storage and transportation, as well as vehicle refueling. Hydrogen storage cylinder banks are responsible for the sealed storage of hydrogen at 45MPa / 90MPa high pressure within the station, and the long-term high-pressure operation of these cylinder banks directly determines the overall intrinsic safety level of the refueling station. With the continuous expansion of the scale of hydrogen refueling station operations in China, safety monitoring and proactive hazard control of hydrogen storage cylinder banks have become essential requirements for the industry.

[0003] The current industry-standard safety monitoring model for hydrogen storage cylinders primarily relies on ambient combustible gas sensors combined with regular manual inspections, with pipelines only equipped with basic pressure detection modules to provide overpressure alerts. This monitoring system operates on a passive, reactive logic: combustible gas sensors only trigger alarms after a significant hydrogen leak has reached the sensor locations; manual inspections rely on visual inspections and simple instrument readings, failing to identify early-stage hazards such as slow pressure leaks; and conventional pressure detection modules only provide over-limit alarm functions, lacking high-precision micro-pressure capture and temperature compensation capabilities, exhibiting multiple inherent shortcomings. First, the early warning system is severely delayed, only able to identify large-scale hydrogen leaks, and unable to detect minor leaks or initial pressure drops caused by minor damage to the cylinders. Second, environmental interference is extremely strong; wind direction, ventilation, and diurnal temperature variations at the site can easily cause false alarms or missed alarms. Third, it cannot identify hidden defects; slow pressure drops caused by cylinder material fatigue, micro-cracks in the inner wall, and aging of the seal are difficult to detect, and long-term accumulation of hidden dangers can easily lead to cylinder failure and the risk of hydrogen combustion and explosion. Fourth, there is no operational condition linkage judgment mechanism; pressure fluctuations caused by dynamic hydrogen filling and adding operations will interfere with pressure interpretation, resulting in low reliability of monitoring data. Fifth, it only has a single-level alarm, which cannot distinguish between minor hidden dangers and serious leaks, and existing equipment is difficult to be compatible with new precision monitoring equipment, resulting in high costs for site upgrades.

[0004] Two types of hydrogen storage pressure monitoring solutions have appeared in existing public literature: CN118517639A Method and Control System for Health Detection of Hydrogen Storage Cylinders in Hydrogen Refueling Stations, and CN116973044A Device and Control Method for Detecting Minor Leaks in On-board Hydrogen Supply Systems. Although both solutions introduce the idea of ​​coordinated acquisition of pressure and temperature, they still have unavoidable technical limitations in the scenario of fixed hydrogen storage cylinder groups in hydrogen refueling stations.

[0005] The CN118517639A method for detecting the health of hydrogen storage cylinders in hydrogen refueling stations and its control system, which calculates hydrogen quality fluctuations by collecting data on the cylinder's internal pressure and temperature to determine leaks, relies solely on a single quality fluctuation threshold for fault identification, thus exhibiting several shortcomings: 1. The valve status monitoring logic is not set up, making it impossible to distinguish the dynamic / static operating conditions corresponding to the start-up and shutdown of the compressor and hydrogen dispenser, and valve opening and closing. Pressure and temperature fluctuations generated by hydrogen charging and discharging operations will directly interfere with the leakage judgment, which is very easy to produce a large number of false judgments. 2. The single-level leakage inspection logic is not uniformly set, which cannot distinguish between minor pressure relief and large-scale leakage, and cannot push maintenance reminders and interlock isolation actions in a tiered manner, resulting in insufficient flexibility in risk handling. 3. The temperature measurement installation structure is not designed to differentiate between the four types of hydrogen storage cylinders (I, II, III, and IV) that are the mainstream types of hydrogen refueling stations. Instead, it adopts a uniform built-in temperature measurement method, which cannot be adapted to the type III and IV hydrogen storage cylinders that are wrapped with carbon fiber and cannot be perforated. The solution has a narrow range of compatibility. 4. Relying solely on a single pressure sensor to collect data, without accompanying high-precision pressure acquisition hardware at the 0.1%FS level, makes it difficult to detect extremely small pressure drops, resulting in insufficient early warning capabilities. 5. It is not compatible with the existing combustible gas sensors and conventional pressure detection modules of the stations, and cannot form a dual protection system of passive monitoring + active early warning, resulting in poor compatibility for the renovation of existing stations.

[0006] Regarding CN116973044A, "A Device and Control Method for Detecting Minor Leaks in On-board Hydrogen Supply Systems," this solution is designed for on-board hydrogen supply systems, a scenario fundamentally different from that of fixed hydrogen refueling station hydrogen storage cylinder groups. Its shortcomings become prominent when implemented at hydrogen refueling stations. 1. The application is for small-capacity hydrogen storage containers on vehicles. It is not suitable for large-capacity hydrogen storage cylinder groups composed of multiple cylinders connected in parallel / series at hydrogen refueling stations. It does not have multi-branch or multi-cylinder group zoning monitoring logic. 2. Leakage is determined by the pressure difference before and after the vehicle is in a dormant state. There is no long-term static continuous monitoring mechanism, so it is impossible to make predictions several hours to several days in advance, resulting in a short warning window. 3. The operation signals of the KV series electric control valves, compressors, and hydrogen dispensers in the entire pipeline are not linked, making it impossible to accurately pinpoint the completely sealed static monitoring period; 4. It only identifies pipeline leaks and lacks the logic to identify micro-damage to the cylinder body, such as fatigue of the cylinder material and micro-cracks in the inner wall. It can only detect pipeline leaks and cannot monitor the aging potential of the hydrogen storage cylinder itself. 5. The alarm logic only provides a single fault warning and lacks an automatic interlocking and shut-off function for the root valve of the hydrogen storage cylinder group, making it impossible to actively isolate the risk source in the event of a serious leak.

[0007] A comprehensive review of industry-standard monitoring methods and existing publicly available technical solutions reveals several shortcomings. These include monitoring lag, significant environmental interference, lack of operational condition linkage for judgment, incompatibility with all types of hydrogen storage cylinders, lack of tiered risk management, poor compatibility with existing equipment, and inability to identify micro-damage to the cylinders. These limitations fail to meet the refined, proactive, and quantitative safety management needs of hydrogen refueling station storage cylinder groups. The industry urgently requires a micro-leakage and micro-damage monitoring system and method for hydrogen storage cylinder groups. This system relies on high-precision synchronous pressure and temperature data acquisition, combined with valve and equipment operational condition linkage for judgment. It should be compatible with all types of hydrogen storage cylinders (I, II, III, and IV), capable of distinguishing between suspected and confirmed micro-leakage, implementing tiered early warning and interlocking, and simultaneously compatible with existing monitoring hardware at the station. This would address the various shortcomings of existing technologies and achieve a technological upgrade from reactive, post-event alarms to proactive, pre-event warnings. Summary of the Invention

[0008] The technical problem to be solved by this invention is to provide a monitoring system and method for micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations. This system overcomes the core defects of existing monitoring technologies for hydrogen storage cylinder groups in hydrogen refueling stations, such as passive alarms, delayed response, lack of micro-damage sensing capability, large environmental interference, high false alarm rate, and inability to identify early micro-leakage hazards. It also solves the technical problem that existing technologies cannot accurately identify early micro-leakage and micro-damage hazards in hydrogen storage cylinder groups.

[0009] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: This invention provides a monitoring system and method for micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations. Through multi-branch high-precision synchronous acquisition of pressure and temperature, valve condition linkage judgment, dynamic deviation correction of pressure-temperature ratio, and a two-level interlocking mechanism, it realizes the technological upgrade of hydrogen storage cylinder monitoring from traditional passive post-event alarm to proactive pre-event early warning, and from macro-fault detection to micro-hazard identification. It solves the technical problem that existing technologies cannot accurately identify early hidden hazards such as micro-leakage of hydrogen storage cylinder groups, cylinder material fatigue, internal wall micro-cracks, and seal aging.

[0010] This invention provides a micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations. It addresses the technical problems of existing hydrogen storage cylinder monitoring, such as lag, susceptibility to environmental interference, inability to distinguish between dynamic and static operating conditions, lack of hierarchical interlocking, and poor compatibility with existing equipment. The system is compatible with existing combustible gas sensors and pressure detection modules in the station. The overall architecture includes hydrogen storage cylinder groups, high-precision pressure transmitters, high-resolution temperature sensors, a central controller, an alarm output module, a valve status detection module, a pressure detection module, a compressor, a hydrogen dispenser, and a temperature detection module. The hydrogen storage cylinder groups consist of 45MPa or 90MPa high-pressure hydrogen storage cylinders connected in parallel or series via seamless high-pressure metal pipelines made of hydrogen-resistant stainless steel. The inlet and outlet high-pressure pipelines of each group of hydrogen storage cylinders are connected to the compressor and the hydrogen dispenser, forming a complete hydrogen storage, pressurization, and refueling operation path. The system adds a complete set of high-precision acquisition units, operating condition discrimination units, and hierarchical alarm interlocking units to the existing conventional monitoring hardware, forming a dual monitoring architecture combining traditional macroscopic passive monitoring with novel microscopic active early warning.

[0011] The specific hardware assembly and signal connection relationships are as follows: Combustible gas sensors are evenly distributed around the hydrogen storage cylinders in the working environment. All combustible gas sensors are electrically connected to the central controller, collecting hydrogen concentration signals in the ambient air in real time and uploading them to the central controller, retaining the traditional leakage and diffusion monitoring function; The pressure detection module includes a conventional pressure gauge and an overpressure switch, which are fixedly installed on the main pipeline and branch pipelines of the hydrogen storage cylinders and electrically connected to the central controller to achieve passive monitoring and basic alarm of pipeline overpressure limit state. The independent upper-level alarm module is eliminated, and a unified alarm output module is used to realize full-level alarm output. The alarm output module integrates on-site audible and visual alarm units and Ethernet remote transmission units. The remote transmission unit connects to the central control room monitoring platform and the mobile terminals of maintenance personnel to realize on-site audible and visual warning + remote information push linkage. It can simultaneously upload on-site alarm data, receive control commands from the central controller, and collaboratively complete graded and scenario-based early warning alarm push and handling prompts.

[0012] Each hydrogen storage cylinder group is independently equipped with a high-precision pressure transmitter. This high-precision pressure transmitter is an industrial-grade device with a range of 0~100MPa and a measurement accuracy of 0.1%FS. It is fixedly installed in the shared gas collection pipeline of the corresponding hydrogen storage cylinder via a threaded seal, eliminating dead zones in the pipeline. It can continuously collect static pressure data inside a single group of cylinders around the clock, outputting 4~20mA analog or digital signals. The pressure signals are uniformly transmitted to the central controller via a pressure detection module. Each hydrogen storage cylinder group is equipped with an independent high-resolution temperature sensor. The high-resolution temperature sensor uses a PT100 platinum resistance sensor with a resolution of not less than 0.01℃ or a high-precision thermocouple. It leverages the thermoelectric effect to achieve precise temperature measurement over a wide temperature range with minimal temperature drift, making it suitable for high-pressure, sealed hydrogen atmosphere environments. The temperature measurement structure is differentiated for four types of standard hydrogen storage cylinders in the industry: Type I is an all-metal forged cylinder; Type II is a circumferentially wound cylinder with a metal liner, where openings are permitted in the cylinder body, allowing the sensor to directly contact the hydrogen medium for temperature measurement via a dedicated sleeve; Type III and Type IV are fully wound metal cylinders, where openings are strictly prohibited to avoid damaging the winding layer. The sensor is attached to the outer wall of the cylinder and equipped with a thermal insulation structure to avoid interference from instantaneous fluctuations in ambient temperature, accurately representing the true temperature of the hydrogen inside the cylinder. Temperature acquisition signals are uniformly uploaded to the central controller via a temperature detection module.

[0013] The valve status detection module is electrically connected to the control terminals of all electric valves, compressors, and hydrogen dispensers, collecting real-time data on the opening and closing status of each electric valve, compressor start / stop signals, and hydrogen dispenser start / stop signals. Through multi-signal linkage, it accurately determines whether the hydrogen storage cylinder is in a completely sealed, static monitoring condition without hydrogen filling or dispensing operations. The central controller uses a Siemens S7-1200 series PLC or an equivalent industrial control computer, with built-in valve control, compressor control, and hydrogen dispenser control modules. It can collect equipment status signals and output control commands to cut off pipelines. The central controller connects to Profi... The central controller establishes a stable bidirectional data transmission link with all sensors and monitoring modules via busPA, Modbus, or CAN bus, centrally aggregating multi-dimensional data on pressure, temperature, valves, and equipment. The central controller has a built-in data storage unit and dedicated monitoring and calculation logic program, which completely retains the original data collected throughout the entire process, deviation calculation data, and alarm records at all levels, generating a traceable operation and maintenance ledger. Based on the dynamic deviation analysis principle of pressure-temperature ratio, it accurately identifies micro-leakage and micro-damage of hydrogen storage cylinders, classifies them into two risk levels according to the deviation value, and outputs three types of control commands: early warning push, audible and visual alarm, and pipeline interlock shut-off.

[0014] This invention abandons the traditional crude mode of single pressure monitoring and single gas concentration monitoring. Based on the core principle of the ideal gas law, it constructs a refined monitoring mechanism with independent acquisition of multiple cylinder groups, synchronous high-frequency sampling of pressure and temperature parameters, and dynamic temperature deviation compensation. Under high-pressure hydrogen storage and closed operation, the diurnal temperature difference and airflow disturbance directly change the pressure value of the sealed cavity, which can easily cause a large number of misjudgments by conventional monitoring systems. This invention independently configures high-precision pressure and temperature acquisition points for each group of hydrogen storage cylinders, synchronously acquires data at high frequency and completes ratio correction calculations, completely eliminating the monitoring error caused by temperature drift. It can capture slow and minute pressure decays that conventional equipment cannot detect, and simultaneously ensures the accuracy of micro-leakage and cylinder micro-damage identification and long-term operational reliability from the hardware and algorithm layers.

[0015] This invention also provides a method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations, which is compatible with the fully automatic operation of the monitoring system described in any of claims 1 to 11. The core mechanism includes six major processes: static operating condition closed-loop determination, raw data filtering and preprocessing, adaptive benchmark ratio establishment, real-time deviation percentage calculation, two-level graded early warning + pipeline interlocking, and full-process data archiving. The detailed steps are as follows: First, a static operating condition closed-loop determination is performed: the valve status detection module continuously collects operating signals from all electric valves, compressors, and hydrogen dispensers; only when all electric valves at the inlet and outlet of the hydrogen storage cylinder are completely closed, the compressor and hydrogen dispenser are continuously stopped, and the stable static time reaches the preset 5 minutes, does the central controller determine to enter the static monitoring mode; during the monitoring process, the operating conditions are continuously verified, and once a valve or equipment is started, the static monitoring is immediately exited, and the determination step is returned to be executed in a loop, completely avoiding interference from dynamic fluctuations in hydrogen charging and adding, and ensuring the effectiveness of the monitoring benchmark and deviation calculation.

[0016] Secondly, the adaptive monitoring baseline value is established: After the system enters the static monitoring mode, the pressure signal from the high-precision pressure transmitter and the temperature signal from the high-precision temperature transmitter are synchronously acquired at a fixed sampling frequency; the raw data is first preprocessed by digital filtering by the central controller to remove abnormal jump data caused by electromagnetic interference and instantaneous airflow impact, and a stable and effective sampling group for 60 consecutive seconds is selected; the pressure and temperature values ​​corresponding to each group are calculated by ratio to obtain a single set. Value, valid for all The arithmetic mean of the values ​​is calculated, and this average is set as the specific monitoring benchmark ratio for this static operating condition to achieve the benchmark value. It adapts and updates according to the environment and operating conditions.

[0017] Then, real-time deviation percentage dynamic calculation is performed: the system continuously maintains a fixed frequency for synchronous acquisition and calculates the pressure-temperature ratio at the current moment in real time. Real-time; the percentage of deviation is calculated using a formula, which intuitively quantifies the subtle attenuation changes in the sealed state inside the bottle.

[0018] Finally, a tiered early warning and alarm system with closed-loop risk management is implemented. The system is divided into two independent handling logics: Level 1 and Level 2. The Level 1 early warning is triggered when the real-time deviation percentage calculated three times consecutively is between 0.5% and 1%, indicating a possible micro-leakage or minor damage to the cylinder. The alarm output module only pushes a special inspection reminder to the central control platform and maintenance mobile phone, without executing pipeline interlocking actions. The Level 2 alarm is triggered when the deviation percentage is greater than 1% three times consecutively, or when a single instantaneous deviation percentage exceeds 2%, indicating a definitive leak. The alarm output module simultaneously drives the on-site audible and visual alarms, and the central controller outputs an interlocking signal through the valve control module, automatically closing the electric valve at the root of the hydrogen storage cylinder and cutting off the high-pressure pipeline to isolate the risk area. Simultaneously, the central controller automatically stores all monitoring raw data, intermediate calculation data, and early warning alarm event records, forming a complete and traceable electronic ledger. This provides quantitative data support for daily safety management, periodic risk assessment, and compliance auditing of hydrogen refueling stations. In static mode, the entire process of acquisition, filtering, calculation, and judgment runs continuously in a loop, achieving all-weather, fully automatic, and proactive identification of potential hazards in hydrogen storage cylinders.

[0019] The micro-leakage and micro-damage monitoring system and method for hydrogen storage cylinder groups in hydrogen refueling stations provided by this invention have the following beneficial effects: 1. This invention possesses ultra-high monitoring sensitivity, enabling early proactive warning of micro-leakage in hydrogen storage tank groups. It employs a 0.1%FS high-precision pressure transmitter and a 0.01℃ high-resolution temperature sensor for dual-parameter collaborative acquisition, accurately capturing minute pressure attenuation changes under micro-leakage conditions. Simultaneously, relying on a real-time temperature compensation and correction mechanism to eliminate interference from ambient temperature fluctuations, it can provide early warning of potential hazards before hydrogen has diffused significantly and before traditional combustible gas probes have responded. The effective early warning time can reach several hours to several days, completely solving the industry pain points of delayed alarms and response delays in traditional monitoring methods.

[0020] 2. This invention can accurately identify microscopic damage to the cylinder body and is compatible with differentiated temperature measurement installation schemes for all types of high-pressure hydrogen storage cylinders (I, II, III, and IV), effectively extending the service life of the hydrogen storage cylinder group. This invention can accurately detect the slow, abnormal pressure decay trend caused by latent defects such as material fatigue, microcracks in the inner wall, and aging seals during long-term operation of the hydrogen storage cylinder group. It provides timely maintenance intervention reminders at the nascent stage of microscopic damage, preventing serious leaks and cylinder ruptures caused by the continued expansion of minor damage, eliminating premature failure and scrapping of hydrogen storage cylinders, significantly reducing equipment wear, and significantly extending the overall service life of the hydrogen storage cylinder group.

[0021] 3. This invention exhibits strong resistance to environmental interference, significantly improving monitoring stability and reliability. It abandons the traditional indirect monitoring method that relies on external hydrogen diffusion concentration, directly collecting and analyzing the inherent core parameters of the internal pressure and temperature of the hydrogen storage tank assembly. The monitoring process is unaffected by external environmental factors such as on-site ventilation, wind direction, air convection, and ambient temperature and humidity, fundamentally eliminating false alarms and missed alarms. This completely solves the shortcomings of traditional monitoring schemes, such as poor reliability and insufficient stability, ensuring the accuracy of long-term continuous monitoring.

[0022] 4. This invention enables quantitative risk management of hydrogen refueling stations, supporting safe and compliant equipment operation. It can output high-precision, continuous, and traceable multi-dimensional monitoring data throughout the entire process, providing sufficient quantitative data for daily safety and compliance self-inspections of hydrogen refueling stations, equipment risk level assessments, precise formulation of operation and maintenance strategies, and fault source analysis. This achieves refined, digital, and standardized management of the safety status of hydrogen storage cylinder groups, comprehensively improving the overall safety and compliance operation level of hydrogen refueling stations.

[0023] 5. This invention incorporates a dynamic temperature compensation and correction mechanism, completely eliminating monitoring misjudgments caused by temperature drift. Based on the ideal gas law, this invention achieves pressure and temperature coupled correction, overcoming the interference of the physical characteristics of passive pressure fluctuations in a high-pressure, sealed hydrogen chamber with temperature changes. It eliminates false pressure anomaly signals caused by sudden changes in ambient temperature, further improving the accuracy of identifying minute pressure changes under static operating conditions and ensuring the authenticity and effectiveness of identifying minor hidden dangers.

[0024] 6. This invention incorporates a comprehensive static precision judgment logic for all operating conditions, ensuring the validity and reliability of monitoring data. By linking the valve status detection module with the collection of valve opening / closing status, compressor and hydrogen refueling machine start / stop signals, this invention accurately pinpoints the stable static monitoring period when the hydrogen storage cylinder group is completely sealed and free from hydrogen filling / refueling interference. This effectively avoids disturbances to monitoring data caused by dynamic operating conditions, ensuring that every potential hazard assessment is based on steady-state valid data, thus improving the reliability and accuracy of monitoring and judgment.

[0025] 7. This invention implements a tiered and layered early warning and alarm system to adapt to the precise operation and maintenance needs of different risk levels. The invention sets up a two-level judgment mechanism: a first-level suspected micro-leakage warning and a second-level deterministic leak alarm. It pushes specific detection reminders for minor, hidden hazards, and triggers audible and visual alarms and equipment interlocking isolation for deterministic leaks. This achieves risk-level management and precise policy implementation, avoiding the operational redundancy or delayed fault handling problems caused by a single alarm mode.

[0026] 8. This invention features automatic fault interlocking and isolation. The central controller drives the electric valve at the root of the hydrogen storage cylinder to shut off, proactively preventing risks and improving the inherent safety level of the equipment. When a deterministic leak is detected, the central controller can instantly output an interlocking control signal to automatically close the valve at the root of the hydrogen storage cylinder group, quickly isolating the faulty cylinder group from the overall pipeline system, preventing the leak from spreading, mitigating the risk of hydrogen combustion and explosion, and significantly improving the operational safety of hydrogen refueling station equipment.

[0027] 9. This invention is compatible with traditional monitoring architectures, has strong equipment modification adaptability, and low implementation costs. Based on the addition of a high-precision active monitoring system, this invention is fully compatible with the existing combustible gas sensors, conventional pressure detection modules, and central control alarm modules of hydrogen refueling stations, constructing a dual-redundant monitoring system of "traditional passive monitoring + new active early warning". It does not require large-scale dismantling of existing equipment and can be directly adapted to the transformation and upgrading of various existing and new hydrogen refueling stations.

[0028] 10. This invention incorporates a data filtering preprocessing mechanism to further enhance the accuracy of identifying minute anomalies. Before establishing the monitoring benchmark ratio, this invention performs filtering and noise reduction preprocessing on the original pressure and temperature data, effectively eliminating abnormal data caused by electromagnetic interference and instantaneous environmental disturbances, ensuring the accuracy and reliability of the benchmark parameters, and providing a stable and accurate data benchmark for subsequent minute deviation calculations and precise judgment of microscopic hidden dangers.

[0029] 11. This invention enables end-to-end data storage and traceability. The central controller has a built-in independent data storage unit to construct a complete digital safety ledger. This invention automatically stores all original monitoring data, benchmark parameters, deviation calculation data, early warning alarms at all levels, and equipment interlock records, forming a continuous, complete, and traceable digital ledger, which can provide authoritative data support for hydrogen refueling station compliance registration, safety audits, accident tracing, and long-term risk management.

[0030] 12. This invention enables 24 / 7 fully automated unattended monitoring, reducing reliance on and risk of human error in maintenance. The invention can automatically and cyclically complete data collection, analysis, and early warning push processes throughout the entire operation and standby period of a hydrogen refueling station, eliminating the need for frequent on-site inspections and reading records. This significantly reduces the workload of manual maintenance and completely avoids safety hazards caused by blind spots in manual inspections and human error in detection.

[0031] 13. This invention features multi-bus adaptability and strong scalability, facilitating intelligent iterative upgrades of the system. The central controller of this invention supports multiple industrial bus communication methods such as Profibus PA, Modbus, and CAN, and can be adapted to sensors and industrial control equipment of different brands. It has strong hardware compatibility, making it easy to connect to station control systems and intelligent operation and maintenance management platforms in the future, and reserving sufficient expansion space for the digital and intelligent upgrade of hydrogen energy safety management and control of hydrogen refueling stations. Attached Figure Description

[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 Flowchart of hydrogen storage and hydrogenation process; Figure 2 This is a process flow diagram of the monitoring system of the present invention; Figure 3 This is the control logic diagram of the monitoring method of the present invention; In the diagram: 1. Hydrogen storage tank assembly; 2. High-precision pressure transmitter; 3. High-resolution temperature sensor; 4. Central controller; 5. Alarm output module; 6. Valve status detection module; 7. Pressure detection module; 8. Compressor; 9. Hydrogen dispenser; 10. Temperature detection module. Detailed Implementation

[0033] The technical solutions of the present invention will be further described below with reference to the embodiments and accompanying drawings: Example 1 This embodiment provides a micro-leakage and micro-damage monitoring system for hydrogen storage cylinder group 1 in a hydrogen refueling station. This system is adapted to the high-pressure hydrogen storage conditions of mainstream hydrogen refueling stations at 45MPa and 90MPa, and is compatible with the existing combustible gas sensor, pipeline pressure detection module 7, and central control alarm module of the hydrogen refueling station, constructing a dual-redundant safety monitoring architecture of "traditional passive monitoring + high-precision active early warning". The system mainly consists of hydrogen storage cylinder group 1, high-precision pressure transmitter 2, high-resolution temperature sensor 3, central controller 4, alarm output module 5, valve status detection module 6, pressure detection module 7, compressor 8, hydrogen dispenser 9, and temperature detection module 10. The fixed assembly, electrical connection relationship, and specific technical parameters of each component are as follows.

[0034] like Figure 1 and Figure 2As shown, the system in this embodiment includes a hydrogen storage cylinder group 1, a high-precision pressure transmitter 2, a high-resolution temperature sensor 3, a central controller 4, an alarm output module 5, a valve status detection module 6, a pressure detection module 7, a compressor 8, and a hydrogen dispenser 9. The hydrogen storage cylinder group 1 is divided into three groups: a first hydrogen storage cylinder group, a second hydrogen storage cylinder group, and a third hydrogen storage cylinder group. Each group of hydrogen storage cylinder groups 1 is independently equipped with a high-precision pressure transmitter 2, PT1, PT2, and PT3. The high-precision pressure transmitter 2 collects the pressure signal and transmits it through the pressure detection module 7. T1, T2, and T3 transmit signals to the central controller 4; each hydrogen storage cylinder group 1 is equipped with a high-resolution temperature sensor 3, and the temperature signal is transmitted to the central controller 4 via the temperature detection module 10; multiple sets of electric valves are installed in the pipeline; among them, the outlet electric valves KV2, KV5, and KV8 are the main outlet valves of the three hydrogen storage cylinder groups 1, and KV1, KV3, KV4, KV6, KV7, and KV9 are booster bypass electric valves; the pipeline of each hydrogen storage cylinder group 1 is connected to the compressor 8 and the hydrogen dispenser 9 via the corresponding electric valve, and the pipeline of the hydrogen dispenser 9 is connected to the receiving equipment. The valve status detection module 6 is electrically connected to all electric valves, compressor 8, and hydrogen dispenser 9, and collects the on / off status of electric valves and equipment start / stop signals; the central controller 4 calculates and determines whether there is a micro-leakage or micro-damage potential in the hydrogen storage cylinder group 1, and realizes graded early warning and interlock control through the alarm output module 5; the central controller 4 has a built-in valve control module, compressor control module, and hydrogen dispenser control module, which can output control signals to drive the corresponding electric valves, compressor 8, and hydrogen dispenser 9.

[0035] Hydrogen storage cylinder group 1 is the main monitoring component of this system. It can use high-pressure hydrogen storage cylinders of 45MPa or 90MPa specifications, and is assembled in parallel or series through high-pressure metal pipelines and matching electric valves. The high-pressure metal pipelines are made of seamless stainless steel, resistant to high pressure and hydrogen embrittlement, possessing high strength, zero leakage, and suitability for long-term high-pressure hydrogen transportation, meeting the requirements of high-pressure closed-loop hydrogen storage in hydrogen refueling stations. The inlet and outlet high-pressure metal pipelines of hydrogen storage cylinder group 1 are connected to compressor 8 and hydrogen dispenser 9 respectively, realizing a complete process for hydrogen pressurization, storage, and refueling. High-precision pressure transmitter 2 is an industrial-grade device with a range of 0~100MPa and a measurement accuracy of 0.1%FS. It is fixedly installed on the gas collection pipelines of each of the three hydrogen storage cylinder groups 1 through threaded sealing connections, eliminating assembly leak dead zones. It can independently and continuously collect static pressure data of the corresponding hydrogen storage cylinder group 1 in real time, supporting the output of 4~20mA analog or digital signals to ensure accurate acquisition and transmission of minute pressure changes.

[0036] High-pressure metal pipelines utilize seamless stainless steel pipes that are resistant to high pressure and hydrogen embrittlement. Specifically, 316L austenitic stainless steel seamless pipes are selected, with 321 and GH4169 nickel-based alloy seamless pipes also available as alternatives. The pipe standards comply with GB / T14976, the standard for seamless stainless steel pipes for fluid transportation. The rated pressure of a single pipe is no less than 100MPa. Wall thickness specifications range from 2.5mm to 6mm, matched to the pipe diameter. The pipe diameter uses 3 / 8-inch and 1 / 2-inch high-pressure specifications commonly used in hydrogen refueling stations. These stainless steel seamless pipes undergo solution heat treatment, resulting in a uniform and stable internal microstructure, effectively suppressing hydrogen-induced cracking and hydrogen embrittlement defects caused by high-pressure hydrogen permeation. Long-term pressure operation poses no risk of intergranular corrosion. All pipe connections employ high-pressure ferrule sealing or automated track argon arc full-penetration welding. After welding, hydrostatic pressure testing and helium mass spectrometry leak detection are performed simultaneously. It features high-strength, permanently leak-free sealed transport characteristics. The pipeline sealing components use fluororubber and polytetrafluoroethylene high-pressure composite gaskets, which are suitable for the entire ambient temperature range of hydrogen refueling stations from -40℃ to 85℃. It will not have problems such as low-temperature hardening or high-temperature swelling failure. It can adapt to complex on-site environments such as day and night temperature differences, outdoor exposure, and low winter temperatures at hydrogen refueling stations. It meets the requirements of high-pressure sealed hydrogen storage and charging / discharging of 45MPa and 90MPa hydrogen refueling stations for long-term continuous transport under all operating conditions. It is specially used for building a high-pressure sealed hydrogen transmission path between hydrogen storage cylinder group 1 and compressor 8 and hydrogen dispenser 9.

[0037] The high-resolution temperature sensor 3 uses a PT100 platinum resistance temperature sensor with a resolution of not less than 0.01℃, which can also be replaced by a high-precision thermocouple of the same accuracy. The high-precision thermocouple is a precision temperature measuring element made based on the thermoelectric effect principle. It has the characteristics of high resolution, small temperature drift, fast response speed, adaptability to high-pressure closed working conditions, and good long-term stability. It can accurately capture small temperature fluctuations of hydrogen and fully meet the high-precision calculation requirements of the pressure-temperature ratio of this system. This system is compatible with the mainstream Type I, Type II, Type III, and Type IV high-pressure hydrogen storage cylinders in hydrogen refueling stations. The structural characteristics and temperature measurement installation methods of each type of hydrogen storage cylinder are designed differently as follows: Type I hydrogen storage cylinder is an all-metal integral forged steel gas cylinder without composite material winding, which has strong overall rigidity and uniform heat conduction of the cylinder wall, and can be opened with temperature measurement installation holes; Type II hydrogen storage cylinder is a composite high-pressure gas cylinder with a metal inner liner and fiber circumferential winding on the outside. The metal inner liner ensures sealing and heat conduction performance and has safe opening conditions for installation. Therefore, for Type I and Type II hydrogen storage cylinders, the high-resolution temperature sensor 3 is inserted into the cylinder through a special sleeve to directly contact the hydrogen medium to collect temperature, ensuring that the collected data closely matches the actual working conditions inside the cylinder. Type III hydrogen storage cylinder 1 is a gas cylinder with a metal inner liner and an outer layer of fully wrapped carbon fiber composite material. The overall pressure bearing relies on the carbon fiber winding layer, and it is strictly forbidden to open or drill holes to damage the structural integrity. Type IV hydrogen storage cylinder 1 is a lightweight high-pressure gas cylinder with a plastic inner liner and an outer layer of fully wrapped carbon fiber. Since the non-metallic inner liner cannot be opened and sealed, for Type III and Type IV hydrogen storage cylinders 1, a high-resolution temperature sensor 3 is attached to the outer wall of the cylinder and is insulated to effectively avoid interference from external airflow and ambient temperature disturbances. It indirectly and accurately characterizes the temperature of hydrogen inside the cylinder by relying on the uniform thermal conductivity of the cylinder wall.

[0038] The central controller 4 is the core data processing and logic control unit of this system. In this embodiment, a Siemens S7-1200 series PLC (Programmable Logic Controller) is used, but it can also be replaced with an industrial control computer with equivalent computing performance. The central controller 4 has a built-in data storage unit, which can completely store the monitoring raw data, calculation results, and alarm records at all levels. The central controller 4 establishes a stable electrical connection with the pressure detection module 7 and the temperature detection module 10 through the analog input module and the Profibus PA fieldbus. It can receive, filter, process, and store multi-dimensional monitoring data in real time, and has a built-in complete monitoring and judgment program. The valve status detection module 6 is electrically connected to the electrical control terminals of all electric valves at the inlet and outlet of the hydrogen storage cylinder group 1, the compressor 8, and the hydrogen dispenser 9, respectively. It collects the on / off status of each electric valve and the start / stop signals of the compressor 8 and the hydrogen dispenser 9 in real time, and accurately determines whether the system is in a dynamic operating condition or a closed static operating condition.

[0039] The alarm output module 5 is electrically connected to the digital output (DO) module of the central controller 4, directly driving the local audible and visual alarms for local alerts. Simultaneously, it transmits all levels of warning and alarm information to the central control room monitoring platform and maintenance personnel's mobile terminals via Ethernet communication, achieving a combined local alert and remote push alarm effect. The existing combustible gas sensor and conventional pressure detection module 7 operate synchronously throughout the system, complementing the high-precision active monitoring function of the high-precision pressure transmitter 2 and high-resolution temperature sensor 3, comprehensively improving the comprehensiveness and reliability of the hydrogen storage cylinder group 1 monitoring. In terms of signal transmission, in addition to the Profibus PA bus, Modbus and CAN buses can also be used to achieve data exchange between devices, adapting to different device networking requirements.

[0040] The alarm output module 5 is electrically connected to the digital output (DO) module of the central controller 4, which can directly drive the local audible and visual alarms to complete local warnings. Simultaneously, it transmits warning and alarm information at all levels to the central control room monitoring platform and the mobile terminals of maintenance personnel via Ethernet communication, achieving a linkage alarm effect of local warning + remote push. The existing combustible gas sensor and conventional pressure detection module 7 of this system work synchronously throughout the process, complementing the high-precision active monitoring function of this invention, comprehensively improving the comprehensiveness and reliability of the monitoring of the hydrogen storage cylinder group 1. In terms of signal transmission, in addition to the Profibus PA bus, Modbus (Modbus Protocol) and CAN (Controller Area Network) buses can also be used to realize data interaction between devices, adapting to different device networking requirements.

[0041] Example 2 In another preferred embodiment, based on Embodiment 1, this embodiment provides a method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations. This method is adapted to the hardware architecture of the micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups described in Embodiment 1. It relies on the internal storage unit of the central controller 4 and a dedicated monitoring and calculation program to automatically execute the monitoring logic. The method integrates six core processes: electric valve operating condition linkage judgment, raw data filtering and preprocessing, pressure-temperature ratio adaptive benchmark establishment, real-time deviation quantification calculation, two-level graded early warning + pipeline interlocking cutoff, and full-process data archiving. Through multi-parameter collaborative acquisition, temperature adaptation correction, dynamic deviation comparison, and graded handling mechanisms, it achieves early and accurate identification of micro-leakage and micro-damage in hydrogen storage cylinder group 1. The specific monitoring steps and judgment logic are as follows: Step 1, Static Condition Determination: The valve status detection module 6 continuously collects all electric valve switch signals, compressor 8 start / stop signals, and hydrogen dispenser 9 start / stop signals in real time. The monitoring system continuously cycles through and verifies the operating conditions. Only when the inlet and outlet valves of the hydrogen storage cylinder group 1 are completely closed, and the compressor 8 and hydrogen dispenser 9 are both in a stopped state, and the duration of this closed and stable static state is greater than or equal to a preset threshold of five minutes, the system automatically shields dynamic operating condition interference and switches to static high-precision monitoring mode. If any electric valve, compressor 8, or hydrogen dispenser 9 moves during the monitoring process, the static monitoring process is immediately exited, and the system returns to this step to continue the condition determination.

[0042] Step 2, Baseline Value Establishment: After the system enters static monitoring mode, the central controller 4 receives pressure data from the high-precision pressure transmitter 2 transmitted by the pressure detection module 7 at a fixed synchronous sampling frequency of 1Hz. Temperature data transmitted by the high-resolution temperature sensor 3 from the temperature detection module 10. After data acquisition, digital filtering preprocessing is performed to remove abrupt changes in data caused by electromagnetic interference and instantaneous airflow disturbances. Stable and effective pressure and temperature paired sampling points within a continuous 60-second interval are then selected. For each pair of corresponding pressure and temperature values, a pressure-temperature ratio calculation is performed to obtain multiple sets of data. Value, then apply to all. The arithmetic mean of the values ​​is calculated, and this mean is defined as the baseline value for this closed static state. Complete the establishment of adaptive baseline parameters; The formula for calculating the value is as follows: (1).

[0043] Step 3, Real-time Deviation Calculation: The system continuously and synchronously collects the real-time pressure of the bottle group at a high frequency of 1Hz. Temperature data Calculate the pressure-to-temperature ratio at the current moment in real time. The real-time deviation percentage is obtained by comparing the benchmark value with the real-time data. Quantitatively characterizes subtle state changes in the sealed cavity of hydrogen storage cylinder group 1, accurately capturing weak parameter anomalies caused by micro-leakage and micro-damage; real-time deviation percentage. The formula is as follows: (2).

[0044] Step 4, Tiered Early Warning and Alarm and Risk Handling: The monitoring system adjusts the alert level based on the real-time deviation percentage. The fluctuation status is divided into a two-level risk management mechanism to accurately match different hazard levels; the first-level early warning is a micro-leakage suspicion warning, when the real-time deviation percentage If three consecutive test results exceed 0.5% but do not exceed 1%, the monitoring system determines that there is a hidden micro-leakage or micro-damage hazard, triggering a Level 1 warning. Alarm output module 5 pushes a text investigation reminder to the central control monitoring platform and the mobile terminals of maintenance personnel, but does not output a pipeline interlock shut-off command. Maintenance personnel are scheduled for a special on-site inspection at a later date. The Level 2 alarm is a deterministic leak fault alarm; when the real-time deviation percentage... Three consecutive deviations exceeding 1%, or a single deviation percentage. When a sudden change of more than 2% occurs, the monitoring system determines that a real hydrogen leak has occurred and immediately triggers a level two audible and visual alarm. At the same time, the central controller 4 outputs an interlock control signal through the built-in valve control module, automatically closing the electric valve at the root of the hydrogen storage cylinder group 1, cutting off the high-pressure pipeline, isolating the faulty cylinder group, and preventing the leak from spreading.

[0045] Throughout the entire monitoring process, the central controller 4's built-in data storage unit automatically archives all raw pressure and temperature data, filtered intermediate data, baseline parameters, deviation calculation results for each cycle, early warning and alarm events at all levels, and electric valve interlocking action records, generating a complete and continuously traceable digital ledger. The ledger data can be exported externally via the bus, providing complete quantitative data support for hydrogen refueling stations' daily safety self-inspection, annual risk assessment, equipment operation and maintenance planning, fault tracing, and compliance auditing.

[0046] Example 3 In another preferred embodiment, based on Embodiment 1, this embodiment provides a method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations. The monitoring method is based on the micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations described in Embodiment 1, and the process is as follows: Figure 3 As shown, relying on the built-in monitoring program of the central controller 4, the system operates fully automatically, enabling proactive identification and tiered handling of micro-leakage and micro-damage to the hydrogen storage cylinder group 1 around the clock. The specific execution steps are as follows: Step 1: Continuous Operational Signal Acquisition and Preliminary Static Condition Judgment. The valve status detection module 6 continuously and in real-time acquires the KV series electric control valve switch signals, compressor 8 start / stop signals, and hydrogen dispenser 9 start / stop signals corresponding to each hydrogen storage cylinder group 1. The central controller 4 continuously judges the static preconditions: the inlet and outlet electric valves of hydrogen storage cylinder group 1 are completely closed, compressor 8 is stopped, and hydrogen dispenser 9 is stopped. If any condition is not met, the timer is reset to zero, and the system maintains dynamic monitoring, continuously cyclically acquiring operational signals; if all conditions are met, the steady-state timing accumulation is initiated.

[0047] Step 2: Static steady-state duration verification. The central controller 4 continuously counts the closed static duration. When the closed stable duration is ≥ five minutes, the operating condition is determined to be stable, and the data disturbance caused by the dynamic operating conditions of hydrogen charging and hydrogen addition is shielded. The system officially enters the static high-precision monitoring mode. If the static duration is less than five minutes, the timing accumulation is continuously maintained and the precision monitoring process is not entered.

[0048] Step 3: Establish steady-state reference values After the detection system enters the static high-precision monitoring mode, it continuously acquires pressure data from the high-precision pressure transmitter 2 for sixty seconds at a synchronous sampling frequency of 1Hz. Temperature data from high-resolution temperature sensor 3 The central controller 4 performs digital filtering on the raw sampled data to remove abnormal data caused by instantaneous impacts and electromagnetic interference; for each group of valid sampled data, the pressure-temperature ratio is calculated according to formula (1) to obtain all valid data. The arithmetic mean of the values ​​is used as the reference value under this steady-state condition. .

[0049] Step 4: After the static real-time cyclic monitoring baseline value is established, the static real-time monitoring cycle begins. The central controller 4 continuously verifies the static conditions: real-time checks the operating status of valves, compressors 8, and hydrogen dispensers 9. Once the static conditions are broken, the static monitoring mode is exited, and the process returns to Step 1 to re-perform the operating condition judgment; if the static conditions are continuously met, the data acquisition and risk assessment process continues to be executed.

[0050] Step 5: The real-time parameter acquisition and deviation calculation system continuously and synchronously acquires real-time pressure and temperature data at a frequency of 1Hz, synchronously stores all raw monitoring data and intermediate calculation data, and constructs a traceable electronic ledger; it also calculates the current pressure-temperature ratio in real time. And according to formula (2), the percentage of real-time deviation is obtained. .

[0051] Step 6: Classified Risk Logic Judgment and Handling. First, determine the triggering condition for a Level 2 alarm: if the calculated values ​​are obtained three times consecutively... or a single time The system triggers a level two audible and visual alarm, outputting an interlock control command through alarm output module 5 to automatically close the root valve of hydrogen storage cylinder group 1, isolating the risk area, and fully recording the alarm information in the ledger. If the level two alarm conditions are not met, the system continues to assess the level one warning conditions: three consecutive... and If a suspected micro-leakage or micro-damage is detected, a Level 1 alert is triggered. A specific detection reminder is pushed to the mobile terminal of maintenance personnel via alarm output module 5, arranging for on-site manual investigation and recording the alert information. If neither the Level 1 nor Level 2 alert conditions are met, no alert command is triggered, and the system continues to execute the real-time monitoring process in a loop.

[0052] Step 7: Archive information and continuously record all Level 1 warning and Level 2 alarm event information into the data ledger; after completing a single logic judgment, the system returns to the static real-time monitoring cycle to continuously carry out uninterrupted monitoring, realizing fully automatic and uninterrupted hidden danger monitoring under the closed static working condition of hydrogen storage cylinder group 1.

[0053] In the preferred embodiment, the hydrogen storage cylinder group 1 is composed of 45MPa or 90MPa hydrogen storage cylinders connected in parallel or series via high-pressure metal pipelines and electric valves for high-pressure hydrogen storage; the high-pressure metal pipelines are made of hydrogen-resistant seamless stainless steel pipes; the above configuration can match the current mainstream high-pressure hydrogen storage process layout of hydrogen refueling stations, without changing the original pipeline connection logic of the hydrogen storage cylinder group 1, and directly superimposing monitoring functions on the existing mature hydrogen storage architecture, resulting in extremely low modification costs.

[0054] In the preferred embodiment, the high-precision pressure transmitter 2 has a range of 0~100MPa and a measurement accuracy of not less than 0.1%FS. It is sealed and installed in the common gas collection pipeline of the hydrogen storage cylinder group 1 to collect the static pressure signal of the hydrogen storage cylinder group 1 in real time. The above settings can cover the full pressure monitoring range of the mainstream 45MPa and 90MPa hydrogen storage cylinder groups 1 in hydrogen refueling stations, capture the tiny pressure fluctuations of one-thousandth caused by micro-leakage, and avoid missing early hidden dangers due to insufficient range redundancy or insufficient accuracy.

[0055] In the preferred embodiment, the high-precision pressure transmitter 2 outputs a 4~20mA analog signal or digital signal, which is fixed to the common gas collection pipeline by a threaded seal to achieve leak-free pressure acquisition. The above settings can be adapted to the general signal interface of the existing industrial control system of the hydrogen refueling station without large-scale modification of the original wiring, while fully meeting the sealing and explosion-proof requirements under high-pressure hydrogen scenarios and eliminating the risk of hydrogen leakage at the acquisition point.

[0056] In the preferred embodiment, the high-resolution temperature sensor 3 has a temperature resolution of not less than 0.01℃. It is installed by attaching to the hydrogen storage cylinder with insulation or by installing it with an inner sleeve, depending on the size of the hydrogen storage cylinder. It is used to collect the hydrogen temperature signal inside the cylinder in real time. The above settings can accurately sense the slight fluctuations in the hydrogen temperature, providing sufficiently fine raw data for subsequent temperature compensation based on the ideal gas law, and eliminating the interference of environmental temperature changes on the pressure monitoring results.

[0057] In the preferred embodiment, the high-resolution temperature sensor 3 is a PT100 platinum resistance temperature sensor or a high-precision thermocouple, with a temperature measurement accuracy of not less than 0.01℃. The above settings can adapt to the special working conditions of high pressure and high explosion in hydrogen refueling stations, have strong long-term operational stability, extremely low data drift, and do not require frequent calibration and maintenance, thus meeting the long-term continuous operation requirements of hydrogen refueling stations.

[0058] In the preferred embodiment, for Type III and Type IV hydrogen storage cylinders, the high-resolution temperature sensor 3 is attached to the outer wall of the cylinder and an insulation structure is provided; for Type I and Type II hydrogen storage cylinders, the high-resolution temperature sensor 3 extends into the cylinder through a sleeve to directly collect the hydrogen temperature. The above settings can take into account the installation characteristics of hydrogen storage cylinders made of different materials, without requiring any opening modifications to non-metallic inner liner hydrogen storage cylinders, while ensuring the accuracy of hydrogen temperature collection inside metal hydrogen storage cylinders, covering all categories of mainstream hydrogen storage cylinder types used in hydrogen refueling stations.

[0059] In the preferred embodiment, the central controller 4 is a Siemens S7-1200 series PLC or an industrial control computer of equivalent performance. It completes data transmission with the valve status detection module 6, pressure detection module 7, and temperature detection module 10 through Profibus PA bus, Modbus bus, or CAN bus. The above settings are compatible with the existing mainstream industrial control bus protocols of hydrogen refueling stations, and the data transmission has strong anti-electromagnetic interference capabilities. Even in the strong electromagnetic environment of hydrogen refueling station filling and unloading, it can still ensure that the data transmission is not lost or delayed.

[0060] In the preferred embodiment, the central controller 4 has a built-in data storage unit that fully stores the collected data, deviation calculation data, and alarm records at all levels, generating a traceable operation and maintenance ledger. This configuration enables local closed-loop retention of full-cycle monitoring data, ensuring no data loss even if the on-site network is temporarily interrupted. All operation records can be retrieved and traced at any time, fully meeting the archiving requirements of hydrogen energy regulatory authorities for hydrogen refueling station safety data. It also provides complete original data support for subsequent assessment of the remaining lifespan of hydrogen storage cylinders and retrospective analysis of potential hazards.

[0061] In the preferred embodiment, the alarm output module 5 includes an on-site audible and visual alarm unit and a remote transmission unit. The remote transmission unit synchronizes the alarm information to the central control room monitoring platform and the mobile terminal of the maintenance personnel via Ethernet. The above settings can achieve dual reach of on-site warning and remote synchronous push. Maintenance personnel do not need to be stationed on-site to obtain the hidden danger information in time, avoiding the problem of untimely handling of hidden dangers when there is no one on-site.

[0062] In the preferred embodiment, the valve status detection module 6 is electrically connected to each electric valve at the inlet and outlet of the hydrogen storage cylinder group 1, the compressor 8, and the hydrogen dispenser 9, respectively, to collect the on / off status of each electric valve and the start / stop signals of the compressor 8 and the hydrogen dispenser 9, so as to determine whether the monitoring system is in a closed static working condition. The above settings can accurately lock the stable monitoring window when the hydrogen storage cylinder group 1 is completely closed and there is no hydrogen filling or unloading action, avoid the drastic pressure and temperature fluctuations during the dynamic hydrogen filling and unloading process, and avoid false triggering under non-hazardous working conditions.

[0063] In the preferred embodiment, in step 2, before establishing the baseline value, the central controller 4 performs filtering preprocessing on the collected pressure and temperature data to remove transient interference and abnormal data, ensuring the baseline value is maintained. The above settings can filter out abnormal jumps in data caused by instantaneous electromagnetic interference and minor vibrations on site, avoid introducing deviations when establishing benchmark values, and ensure the reliability of subsequent deviation calculation results from the source.

[0064] In the preferred embodiment, the trigger condition for the Level 1 warning in step 4 is: the percentage value of the real-time deviation obtained from three consecutive data collections. If the leakage rate exceeds 0.5% but does not reach 1%, the system determines that there is a suspected micro-leakage, triggers a level-one warning, and pushes a special detection reminder to the operation and maintenance terminal. The above settings can trigger a low-level reminder at the initial stage of potential hazards, guide operation and maintenance personnel to conduct targeted investigations in advance, and complete intervention before the hazard expands, avoiding unnecessary station-wide shutdowns and ensuring the operational efficiency of hydrogen refueling stations.

[0065] In the preferred embodiment, the trigger condition for the secondary alarm in step 4 is: the real-time deviation percentage value obtained from three consecutive data acquisitions. If the percentage deviation exceeds 1%, or if the percentage deviation of a single data collection and calculation changes abruptly by more than 2%, the system will immediately trigger a level two audible and visual alarm. The above settings can trigger a strong warning at the first moment when a hidden danger develops rapidly. This will prevent frequent false alarms due to excessively low threshold settings from interfering with normal operation, and will also prevent missing the critical window for handling hidden dangers due to excessively high threshold settings.

[0066] In the preferred embodiment, after the secondary alarm is triggered, the central controller 4 synchronously outputs an interlock control signal, automatically closes the root valve of the hydrogen storage cylinder group 1, cuts off the pipeline passage of the faulty cylinder group, and completes the isolation of the risk area. The above settings can complete the physical isolation of the faulty cylinder group without manual intervention after the alarm is triggered, avoid the risk of further spread of hidden dangers and explosion, and completely limit the scope of the accident to the area of ​​a single cylinder group.

[0067] In the preferred embodiment, the central controller 4 automatically stores all monitoring data, deviation calculation data, and early warning alarm records to form a traceable data ledger, providing quantitative data support for hydrogen refueling station risk assessment, compliant operation and maintenance, and operation and maintenance decisions. The above settings can completely retain monitoring and operation data throughout the entire cycle, meet the traceability requirements of hydrogen energy regulatory authorities for hydrogen refueling station safety data, and also provide complete original data basis for subsequent hydrogen storage cylinder life assessment.

[0068] In the preferred embodiment, the monitoring system continuously and cyclically executes the data acquisition, data preprocessing, deviation calculation, risk assessment, and early warning alarm process in static monitoring mode, updating the monitoring data in real time. Once a disruption of the static operating condition is detected, the precision monitoring process is immediately terminated, and the system returns to step 1 to re-assess the static conditions, achieving all-weather, fully automatic, and proactive early warning monitoring of micro-damage and micro-leakage in the hydrogen storage cylinder group 1. With the above settings, no periodic manual intervention is required, and the system can be monitored 24 hours a day without interruption, fully covering the non-operational nighttime idle period of the hydrogen refueling station, filling the monitoring gaps of traditional manual inspections, and achieving all-day, blind-spot-free hazard identification.

[0069] In summary, the micro-leakage and micro-damage monitoring system and method for hydrogen storage cylinder groups in hydrogen refueling stations proposed in this invention rely on a multi-group independent hydrogen storage cylinder group 1 branch acquisition architecture, combined with high-precision pressure transmitter 2, high-resolution temperature sensor 3 synchronous sensing means and pressure-temperature ratio dynamic deviation analysis logic, to overcome the limitations of existing hydrogen refueling station hydrogen storage facilities that rely on combustible gas probes and manual inspections, resulting in monitoring lag, the ability to only identify large-scale leaks, and susceptibility to environmental interference. It enables the early identification and graded handling of micro-leakage and early-stage micro-damage hazards in hydrogen storage cylinder group 1 under closed operating conditions.

[0070] At the hardware architecture level, this invention is compatible with existing combustible gas sensors and pressure detection modules 7 in hydrogen refueling stations, and adds an independent high-precision sensing and operating condition discrimination hardware unit to form a dual protection system that combines passive monitoring and active early warning. It does not require large-scale modification of existing station equipment and is suitable for upgrading existing hydrogen refueling stations and supporting the use of newly built hydrogen refueling stations.

[0071] This invention provides differentiated temperature measurement installation methods for hydrogen storage cylinder groups 1 with different structures of Type I, Type II, Type III, and Type IV. Combining high-pressure metal pipelines and pipeline topologies composed of multiple sets of electric valves, it can be adapted to mainstream specifications of high-pressure hydrogen storage cylinder groups 1 on the market. Based on the constraints of the cylinder structure, it selects either built-in direct temperature measurement or external wall-attached indirect temperature measurement methods to ensure the effectiveness of monitoring data for various types of hydrogen storage cylinder groups 1.

[0072] This invention sets up a signal linkage judgment logic for valve status detection module 6, compressor 8, and hydrogen refueling machine 9. Precision monitoring is only activated after the hydrogen storage cylinder group 1 reaches a stable and sealed static working condition, eliminating the interference of dynamic operation processes such as hydrogen filling and hydrogen refueling on the collected data, and ensuring that the basis for hazard identification is stable and reliable steady-state data.

[0073] This invention abandons the single pressure monitoring or single environmental hydrogen concentration monitoring mode. It uses a high-precision pressure transmitter 2 and a high-resolution temperature sensor 3 to collect data and perform dual-parameter coupling calculations to eliminate the data drift caused by environmental temperature fluctuations. It can capture slow and minute pressure decay changes that cannot be identified by conventional monitoring methods, and detect hidden defects such as bottle material fatigue, seal aging, and micro-cracks in the inner wall at an earlier time.

[0074] This invention relies on a two-level early warning and handling mechanism based on the central controller 4 to distinguish between suspected micro-leakage and confirmed leakage fault status. The alarm output module 5 performs different handling actions, such as information push, audible and visual alarm, and electric valve interlock isolation, taking into account both the flexibility of operation and maintenance and the ability to quickly block major fault risks.

[0075] This invention utilizes a central controller 4 to fully retain raw data, baseline parameters, deviation calculation results, and early warning alarm records at all levels throughout the entire monitoring process, forming a continuously traceable data ledger. This provides quantitative data support for the daily safety management, risk assessment, and compliant operation and maintenance of hydrogen refueling stations, and promotes the transformation of hydrogen storage facility safety management from post-fault handling to routine state prediction.

Claims

1. A micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups at hydrogen refueling stations, characterized in that: The system includes a hydrogen storage cylinder group (1), a combustible gas sensor, and an alarm output module (5). The hydrogen storage cylinder group (1) is connected to the compressor (8) and the hydrogen dispenser (9) through a high-pressure pipeline, forming a hydrogen storage and refilling passage. A high-precision pressure transmitter (2) and several electric valves are installed on the passage. The high-precision pressure transmitter (2) collects pressure signals and transmits them to the central controller (4) via the pressure detection module (7). The combustible gas sensor is installed in the surrounding environment of the hydrogen storage cylinder group (1) and is electrically connected to the central controller (4) to monitor the concentration of hydrogen leakage in the environment and upload the detection signal. A high-resolution temperature sensor (3) is installed on the hydrogen storage cylinder group (1) to collect temperature data. The temperature signal is transmitted to the central controller (4) via the temperature detection module (10); the valve status detection module (6) collects the operating status of each electric control valve, compressor (8), and hydrogen dispenser (9) and uploads it to the central controller (4); the central controller (4) is electrically connected to the alarm output module (5), valve status detection module (6), pressure detection module (7), and temperature detection module (10) respectively; the central controller (4) has a built-in monitoring logic program, which completes the early identification and graded alarm control of micro-leakage and micro-damage of the hydrogen storage cylinder group (1) based on the dynamic deviation of the pressure-temperature ratio, and is compatible with traditional monitoring functions to achieve dual protection of active early warning and passive monitoring.

2. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The hydrogen storage cylinder group (1) consists of hydrogen storage cylinders connected in parallel or in series via high-pressure metal pipelines and electric valves, and is used for the closed storage of high-pressure hydrogen; the high-pressure metal pipelines are made of seamless stainless steel pipes resistant to hydrogen embrittlement.

3. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The high-precision pressure transmitter (2) has a range of 0~100MPa and a measurement accuracy of not less than 0.1%FS. It is sealed and installed in the common gas collection pipeline of the hydrogen storage cylinder group (1) and is used to collect the static pressure signal of the hydrogen storage cylinder group (1) in real time.

4. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The high-precision pressure transmitter (2) outputs a 4~20mA analog signal or digital signal, which is fixed to the common gas collection pipeline by a threaded seal to achieve leak-free pressure acquisition.

5. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The high-resolution temperature sensor (3) has a temperature resolution of not less than 0.01℃. It is installed by attaching heat insulation or by installing an inner sleeve on hydrogen storage cylinders of different specifications, and is used to collect hydrogen temperature signals in the cylinder in real time.

6. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The high-resolution temperature sensor (3) is a PT100 platinum resistance temperature sensor or a high-precision thermocouple, with a temperature measurement accuracy of not less than 0.01℃.

7. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 6, characterized in that: For Type III and Type IV hydrogen storage cylinders, the high-resolution temperature sensor (3) is attached to the outer wall of the cylinder and a heat preservation structure is provided; for Type I and Type II hydrogen storage cylinders, the high-resolution temperature sensor (3) is inserted into the cylinder through a sleeve to directly collect the hydrogen temperature.

8. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The central controller (4) is an industrial control computer that transmits data to the valve status detection module (6), pressure detection module (7), and temperature detection module (10) via Profibus PA bus, Modbus bus, or CAN bus.

9. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The central controller (4) has a built-in data storage unit that fully stores the data collected throughout the process, deviation calculation data, and early warning alarm records at all levels, and generates a traceable operation and maintenance ledger.

10. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The alarm output module (5) includes an on-site audible and visual alarm unit and a remote transmission unit. The remote transmission unit synchronizes the alarm information to the central control room monitoring platform and the mobile terminal of the operation and maintenance personnel via Ethernet.

11. The micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations according to claim 1, characterized in that: The valve status detection module (6) is electrically connected to each electric valve, compressor (8) and hydrogen dispenser (9) at the inlet and outlet of the hydrogen storage cylinder group (1) respectively. It is used to collect the opening and closing status of each electric valve and the start and stop signals of the compressor (8) and hydrogen dispenser (9) to determine whether the monitoring system is in a closed static working condition.

12. A method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations, applied to the micro-leakage and micro-damage monitoring system for hydrogen storage cylinder groups in hydrogen refueling stations as described in any one of claims 1 to 11, characterized in that, Includes the following steps: Step 1, Static operating condition determination: The valve status detection module (6) collects the operating status signals of the electric valve, compressor (8), and hydrogen dispenser (9) in real time. When the inlet and outlet electric valves corresponding to the hydrogen storage cylinder group (1) are completely closed, the compressor (8) and hydrogen dispenser (9) are both stopped, and the stable duration reaches the preset duration, the system enters the static monitoring mode. If the operating conditions change, the static monitoring mode is exited and the operating condition determination is continuously carried out in a loop. Step 2: Establish monitoring benchmark value: After entering the static monitoring mode, the central controller (4) synchronously collects the real-time pressure and real-time temperature of the hydrogen storage cylinder group (1) at a fixed frequency, selects stable data that has no abnormal fluctuations within 60 consecutive seconds, performs a ratio calculation on the corresponding pressure data and temperature data of each group, calculates multiple pressure-temperature ratios, calculates the arithmetic mean of all pressure-temperature ratios, and uses the average value as the monitoring benchmark ratio. Step 3, Real-time Deviation Calculation: Continuously collect pressure and temperature synchronously at a fixed frequency, calculate the current pressure-temperature ratio in real time, calculate the difference between the current pressure-temperature ratio and the preset monitoring benchmark ratio, take the absolute value of the difference and then calculate the ratio with the monitoring benchmark ratio to finally obtain the real-time deviation percentage. Step 4, graded early warning and alarm: Based on the continuous change of the real-time deviation percentage, graded early warning or alarm commands are triggered to complete the risk assessment and risk handling of micro-leakage and micro-damage of the hydrogen storage cylinder group (1).

13. The method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations according to claim 12, characterized in that: In step 2, before establishing the baseline value, the central controller (4) performs filtering preprocessing on the collected pressure and temperature data to remove instantaneous interference abnormal data and ensure the accuracy of the baseline value.

14. The method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations according to claim 12, characterized in that, The triggering condition for the first-level warning in step 4 is: the real-time deviation percentage value obtained from three consecutive data collections exceeds 0.5% but does not reach 1%. The system determines that there is a micro-leakage or micro-damage to the screen, triggers the first-level warning, and the alarm output module (5) pushes special detection reminder information to the central control room / maintenance terminal and does not perform pipeline interlocking actions.

15. The method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations according to claim 12, characterized in that, The triggering condition for the secondary alarm in step 4 is: if the real-time deviation percentage value obtained from three consecutive acquisitions exceeds 1%, or if the real-time deviation percentage value obtained from a single acquisition shows a sudden and abrupt change of more than 2%, the monitoring system will immediately trigger the secondary audible and visual alarm.

16. The method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations according to claim 15, characterized in that: After the secondary alarm is triggered, the central controller (4) outputs an interlock control signal, automatically closes the root valve of the hydrogen storage cylinder group (1), cuts off the pipeline passage of the faulty cylinder group, and completes the isolation of the risk area.

17. The method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations according to claim 14 or 15, characterized in that: The central controller (4) automatically stores all monitoring data, deviation calculation data, and early warning alarm records to form a traceable data ledger, providing quantitative data support for hydrogen refueling station risk assessment, compliant operation and maintenance, and operation and maintenance decisions.

18. The method for monitoring micro-leakage and micro-damage of hydrogen storage cylinder groups in hydrogen refueling stations according to claim 12, characterized in that: The monitoring system continuously and cyclically executes the data acquisition, data preprocessing, deviation calculation, risk assessment and early warning alarm process in static monitoring mode, and updates the monitoring data in real time. Once a static condition is detected to be damaged, the precision monitoring process is immediately terminated and the static condition is re-evaluated in step 1 to achieve all-weather, fully automatic active early warning monitoring of micro-damage and micro-leakage of the hydrogen storage cylinder group (1).

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