Hydrogen production system safety linkage control method and system based on multistage hydrogen concentration threshold values
By adopting a multi-level hydrogen concentration threshold safety linkage control method, the problem of inflexible safety response in hydrogen production systems has been solved, enabling refined management and hierarchical control of hydrogen leakage, and improving system safety and production continuity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INNER MONGOLIA ACADEMY OF SCIENCE & TECHNOLOGY
- Filing Date
- 2025-12-30
- Publication Date
- 2026-04-28
AI Technical Summary
The existing hydrogen production system has a single safety control strategy, which leads to overreaction in the event of minor leaks, inability to accurately locate the leak source, and lack of graded and coordinated response, thus failing to effectively prevent the accident from escalating.
A multi-level hydrogen concentration threshold safety linkage control method is adopted. Multiple hydrogen concentration sensors monitor in real time, and first-level, second-level, and third-level thresholds are set to trigger actions such as alarm, local isolation, and global shutdown, respectively. Combined with the priority response of flame detectors, hierarchical control is achieved.
It enables refined management of hydrogen leaks, early warning, tiered response, reduced production disruptions, precise isolation of leak sources, and improved safety and production continuity.
Smart Images
Figure CN121934499A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of industrial process safety control and automation technology, and in particular to a safety linkage control method and system for a hydrogen production system based on multi-level hydrogen concentration thresholds. Background Technology
[0002] Hydrogen is a clean energy carrier, and the technology for producing it through water electrolysis is becoming increasingly mature. However, hydrogen is flammable and explosive, and hydrogen leakage is a major safety risk during the operation of hydrogen production systems. Currently, most hydrogen production systems employ relatively simple and crude safety control strategies, typically setting a fixed hydrogen concentration alarm threshold (e.g., 1%). Once the detected hydrogen concentration exceeds this single threshold, the system triggers the highest level of response, such as a complete system emergency shutdown. This control method has significant drawbacks: First, for minor, initial leaks, directly implementing an emergency shutdown would cause unnecessary production interruptions, which is an overreaction and affects production efficiency; Secondly, the inability to provide early warning and gradual response to the worsening leak situation meant that the opportunity to control the situation and prevent its escalation in the early stages of the accident through intermediate measures such as ventilation and local isolation was missed. In addition, a single response action lacks specificity and cannot effectively locate the leak source and isolate it accurately, which may lead to an expansion of the scope of the accident's impact.
[0003] Furthermore, although some industry standards (such as the "Design Code for Hydrogen Stations" GB50177) stipulate the trigger thresholds for specific safety actions (such as starting the emergency fan at 0.4%), these regulations are isolated and scattered, and do not form a complete, automated, hierarchical and coordinated response control logic system.
[0004] Therefore, in view of the above problems, it is necessary for the present invention to provide a safety control method that can perform refined and intelligent management of hydrogen leakage risks. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a safety linkage control method and system for hydrogen production systems based on multi-level hydrogen concentration thresholds, so as to solve the problems of inflexible and inaccurate safety response in the existing technology.
[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention discloses a safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds, comprising: Step S1: Signal acquisition, real-time acquisition of the detection values of multiple hydrogen concentration sensors deployed in various areas of the hydrogen production system; Step S2: Threshold determination, compare the detected value in step S1 with multiple preset concentration thresholds, the multiple concentration thresholds include at least a first-level threshold, a second-level threshold and a third-level threshold arranged from low to high; Step S3: Based on the comparison results, execute the corresponding linkage control action: An alarm is triggered when a hydrogen leak is detected but the first-level threshold is not reached. When the detected value reaches or exceeds the first-level threshold, a first-level response is triggered, which initiates alarm activation and emergency ventilation. When the detected value reaches or exceeds the second-level threshold, a second-level response is triggered, which, while maintaining the first-level response action, also cuts off the hydrogen valve in the associated area. When the detected value reaches or exceeds the third-level threshold, a third-level response is triggered, which, while maintaining the second-level response action, adds the activation of the system emergency shutdown procedure; Step S4: The flame signal is given priority response, directly triggering the highest level response action, including starting the system emergency shutdown.
[0007] Furthermore, steps S4 and S3 are performed in parallel, with real-time monitoring of the flame detector's status; when a flame alarm signal is received, the current hydrogen concentration value is ignored, and a level-three response action is directly and forcibly executed, and the fire extinguishing system is immediately activated.
[0008] Furthermore, the first threshold is a hydrogen volume concentration of 0.4% in the air, the second threshold is 1.0%, and the third threshold is 1.6%.
[0009] Furthermore, in step S3, when the secondary response is triggered, the step of locating and highlighting the area where the alarm sensor is located in the host computer human-machine interface is also included.
[0010] Furthermore, in step S3, when a level 3 response is triggered or a flame alarm signal is received, a step of sending a start or pre-start signal to the fire extinguishing system is also included.
[0011] The invention provides a linkage control system for implementing the aforementioned safety linkage control method for hydrogen production systems based on multi-level hydrogen concentration thresholds, comprising: A signal acquisition module, a logic processing module connected to the signal acquisition module, and a control output module connected to the logic processing module; The signal acquisition module is used to obtain hydrogen concentration detection values and flame signals; The logic processing module is used to perform the threshold comparison and graded response decision; The control output module is used to output control commands to execute the alarm, emergency ventilation, valve shut-off, system shutdown and fire extinguishing system activation actions.
[0012] Furthermore, the logic processing module is integrated into a programmable logic controller, a distributed control system, or a safety instrumented system.
[0013] In the above technical solution, the present invention provides a safety linkage control method and system for hydrogen production system based on multi-level hydrogen concentration thresholds, which effectively solves the problems of inflexible and inaccurate safety response in the prior art, realizes early warning, graded control and emergency protection of hydrogen leakage risk, thereby minimizing unnecessary interference to production while ensuring safety. Compared with the prior art, the present invention has the following beneficial effects: First, by setting multi-level concentration thresholds, the entire process of hydrogen leak events, from "early warning" to "control" and then to "emergency protection," is managed in a refined and automated manner, resulting in a more intelligent and reasonable response strategy. Secondly, proactive dilution through forced ventilation in the early stages of a leak (Level 1 response) effectively reduced the risk of hydrogen accumulation, prevented minor leaks from escalating into serious accidents, improved the inherent safety level of the system, and prevented problems before they occurred. In addition, the Level 2 response combines sensor location information to shut off valves in the relevant areas instead of shutting down the entire line, achieving precise isolation of the fault, minimizing the scope of downtime, reducing the impact on production operations and economic losses, and achieving precise isolation and loss reduction. In addition, the flame detector signal is given the highest decision-making authority, ensuring that in the most dangerous situation of open flame, the system can bypass the concentration judgment logic and enter the highest level of protection as quickly as possible, thus buying valuable time for personnel evacuation and property protection and providing the highest level of safety guarantee. Attached Figure Description
[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.
[0015] Figure 1 This is a logic flowchart of the safety linkage control method for hydrogen production systems based on multi-level hydrogen concentration thresholds disclosed in this invention. Detailed Implementation
[0016] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.
[0017] See Figure 1 As shown; An invention provides a safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds, comprising the following steps: Step S1: Signal acquisition, real-time acquisition of the detection values of multiple hydrogen concentration sensors deployed in various areas of the hydrogen production system; Step S2: Threshold determination. The detected value is compared with multiple preset concentration thresholds. The multiple concentration thresholds include at least a first-level threshold, a second-level threshold, and a third-level threshold, and satisfy the following condition: first-level threshold < second-level threshold < third-level threshold. Specifically, the first-level threshold is the volume concentration of hydrogen in air of 0.4%, the second-level threshold is 1.0%, and the third-level threshold is 1.6%. Step S3: Hierarchical linkage control. Based on the comparison results, execute the corresponding linkage control actions: When a hydrogen leak is detected but the first-level threshold is not reached, an alarm is triggered. When the detection value of any sensor reaches or exceeds the first-level threshold, a first-level response is triggered: the audible and visual alarm is activated, and the emergency ventilation system is activated in conjunction with it. When the detection value of any sensor reaches or exceeds the second-level threshold, the second-level response is triggered: while maintaining the first-level response action, the hydrogen pipeline valve in the area where the sensor is located is automatically cut off, and the alarm area is highlighted in the host computer human-machine interface to realize the location and local isolation of the leak source. When the detection value of any sensor reaches or exceeds the third-level threshold, a third-level response is triggered: while maintaining the aforementioned response actions, the system's global emergency shutdown procedure is initiated, and a pre-start signal is sent to the gas extinguishing system; Step S4: Flame priority response, in parallel, real-time monitoring of the flame detector status; when a flame alarm signal is received, ignoring the current hydrogen concentration value, directly enforce the three-level response action and immediately activate the fire extinguishing system. This method starts from signal acquisition, goes through multi-level threshold judgment, triggers different response actions respectively, and uses parallel processing and priority triggering control logic for flame signals to achieve early warning, graded control and emergency protection of hydrogen leakage risk, thereby minimizing unnecessary interference to production while ensuring safety.
[0018] The invention provides a linkage control system for implementing the above-mentioned safety linkage control method for hydrogen production systems based on multi-level hydrogen concentration thresholds. The system includes: A signal acquisition module configured to receive signals from multiple hydrogen concentration sensors and at least one flame detector; The logic processing module, which is connected to the signal acquisition module, pre-stores the first, second, and third level concentration thresholds and linkage control logic for threshold judgment and response decision-making. The control output module, which is connected to the logic processing module, is configured to send control signals to the audible and visual alarm, emergency ventilation system, hydrogen pipeline valves, system main control unit, and fire extinguishing system according to the decision instructions of the logic processing module.
[0019] Preferably, the logic processing module is integrated into a programmable logic controller (PLC), a distributed control system (DCS), or a safety instrumented system (SIS).
[0020] See Figure 1 As shown, a specific embodiment is as follows: The core of the linkage control system is a programmable logic controller (PLC). The signal acquisition module consists of the PLC's analog and digital input modules, used to receive the 4-20mA current signal output from the hydrogen concentration sensor and the relay switch signal from the flame detector. The logic processing module is the user program running in the PLC, which is programmed as follows: Figure 1 The control logic is shown below. The control output module is a digital output module of the PLC, used to control components such as relays and contactors, thereby driving the audible and visual alarms, fans, valve actuators, and fire extinguishing system control panel; Operating Process: During system operation, the PLC continuously monitors the readings of all hydrogen concentration sensors (X1, X2, ..., Xn). If hydrogen leaks but the level does not reach the first-level threshold (below 0.4%), the PLC activates an audible and visual alarm and a high-frequency flashing warning light via its output module. Assuming the reading of sensor X3 rises to 0.45%, exceeding the first-level threshold of 0.4%, the PLC immediately activates the audible and visual alarm and the high-frequency flashing warning light via the output module, while simultaneously closing the start-up circuit of the emergency exhaust fan. At this time, the operator receives a "Level 1 Alarm" notification on the host computer, but the system continues to operate.
[0021] If the leakage worsens and the X3 reading rises to 1.2%, exceeding the second-level threshold of 1.0%, the PLC, while maintaining its original operation, will output a signal to shut off the emergency shut-off valve of the area monitored by sensor X3 (such as the ALK electrolytic cell outlet valve group). Simultaneously, the icon for that area on the host computer screen will turn red and flash, thus locating the leak.
[0022] If the situation continues to deteriorate and the X3 reading reaches 1.6% or higher, a Level 3 response will be triggered. The PLC will send an emergency stop signal to the system's main controller, stopping the operation of all electrolyzers and compressors, and send a "fire confirmation" or "pre-start" signal to the heptafluoropropane fire suppression system control panel, putting the fire suppression system into a delayed start-up preparation state.
[0023] At any time, as long as any flame detector (such as F1) detects an open flame and sends a signal, the PLC will immediately interrupt the current concentration judgment logic, directly execute all actions of the three-level response, and immediately send a start command to the fire extinguishing system (or start it after confirmation) to achieve the fastest fire extinguishing response.
[0024] This invention is not limited to the above-described embodiments. The specific values of the first, second, and third thresholds can be adjusted according to different application scenarios and security standards.
[0025] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.
Claims
1. A safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds, characterized in that, include: Step S1: Signal acquisition, real-time acquisition of the detection values of multiple hydrogen concentration sensors deployed in various areas of the hydrogen production system; Step S2: Threshold determination, compare the detected value in step S1 with multiple preset concentration thresholds, the multiple concentration thresholds include at least a first-level threshold, a second-level threshold and a third-level threshold arranged from low to high; Step S3: Based on the comparison results, execute the corresponding linkage control action: When a hydrogen leak is detected but the first-level threshold is not reached, an alarm is triggered. When the detected value reaches or exceeds the first-level threshold, a first-level response is triggered, which initiates alarm activation and emergency ventilation. When the detected value reaches or exceeds the second-level threshold, a second-level response is triggered, which, while maintaining the first-level response action, also cuts off the hydrogen valve in the associated area. When the detected value reaches or exceeds the third-level threshold, a third-level response is triggered, which, while maintaining the second-level response action, adds the activation of the system emergency shutdown procedure; Step S4: The flame signal is given priority response, directly triggering the highest level response action, including starting the system emergency shutdown.
2. The safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds according to claim 1, characterized in that: Step S4 runs in parallel with step S3, monitoring the status of the flame detector in real time. When a flame alarm signal is received, the current hydrogen concentration value is ignored, and a level 3 response action is directly and forcibly executed, and the fire extinguishing system is immediately activated.
3. The safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds according to claim 1, characterized in that: The first threshold is 0.4% of the volume concentration of hydrogen in the air, the second threshold is 1.0%, and the third threshold is 1.6%.
4. The safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds according to claim 1, characterized in that: In step S3, when the secondary response is triggered, the step of locating and highlighting the area where the alarm sensor is located in the host computer human-machine interface is also included.
5. The safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds according to claim 1, characterized in that: In step S3, when a level 3 response is triggered or a flame alarm signal is received, the step of sending a start or pre-start signal to the fire extinguishing system is also included.
6. A linkage control system for implementing the safety linkage control method for a hydrogen production system based on multi-level hydrogen concentration thresholds as described in any one of claims 1-5, characterized in that, include: A signal acquisition module, a logic processing module connected to the signal acquisition module, and a control output module connected to the logic processing module; The signal acquisition module is used to obtain hydrogen concentration detection values and flame signals; The logic processing module is used to perform the threshold comparison and graded response decision; The control output module is used to output control commands to execute alarm, emergency ventilation, valve shut-off, system shutdown and fire extinguishing system activation actions.
7. The linkage control system of the hydrogen production system safety linkage control method based on multi-level hydrogen concentration thresholds according to claim 6, characterized in that: The logic processing module is integrated into a programmable logic controller, a distributed control system, or a safety instrumented system.