A hydrogen gas leak monitoring and power-off control system and method

Abstract

This invention discloses a hydrogen leak monitoring and power-off control system and method, relating to the field of safety protection for hydrogen-related operations. The system includes: a hydrogen detection and signal conditioning unit, used to collect hydrogen concentration signals and convert them into analog voltage signals, perform linear amplification and filtering, and output a voltage signal with a standard range; a control unit, connected to the hydrogen detection and signal conditioning unit, used to generate control commands; an execution unit, connected to the control unit and connected to the driving module of the hydrogen-related work tool, used for on / off control; a manual reset unit, connected to the control unit, used to input a reset trigger signal in the power-off locked state; and a voltage conversion unit, connected to the power module of the hydrogen-related work tool and connected to other units of the system, used to provide a stable working power supply. This solution achieves system-level integration, risk classification perception, and adaptive operation and maintenance for hydrogen leak monitoring and power-off control of hydrogen-related work tools.

Description

Technical Field

[0001] This invention relates to the field of safety protection for hydrogen-related operations, and more specifically to a hydrogen leak monitoring and power-off control system and method. Background Technology

[0002] The rapid development of the hydrogen energy industry has driven the continuous expansion of hydrogen-related work scenarios, such as the construction of hydrogen refueling stations, the maintenance of hydrogen fuel cells, and the laying of hydrogen pipelines. Hydrogen itself has characteristics such as a wide explosion limit, low ignition energy, and strong concealment of leaks, which means that the power tools used in the operation must have special safety protection capabilities for hydrogen leaks in order to effectively prevent safety accidents caused by sparks from tool operation igniting leaked gas.

[0003] In existing hydrogen-related work scenarios, most power tools are ordinary explosion-proof tools, whose protection logic focuses on basic electrical safety aspects such as leakage prevention and spark prevention, without integrating hydrogen leak detection functions. Although some scenarios are equipped with independent hydrogen alarm devices, these devices have no electrical or communication connection with the power tool itself. After detecting a leak, they can only issue an audible and visual warning, requiring operators to manually judge and shut down the tool. This fragmented protection architecture results in a significant time window between the occurrence of a leak and the power cut-off. Operators are prone to judgment delays or operational errors in emergency situations, making it difficult to meet the engineering requirements of millisecond-level power cut-off after a leak occurs.

[0004] In contrast, a few fixed devices have integrated hydrogen detection and power-off protection solutions. However, these solutions are designed for static, clean indoor environments. The sensor installation method, circuit anti-interference capability, and protection level cannot meet the requirements of complex working conditions such as frequent movement, dust, high humidity, and mechanical vibration in hydrogen-related operations. When deployed on-site, problems such as sensor zero-point drift, frequent false alarms, and even component failure may occur, rendering the protection function practically unusable.

[0005] Furthermore, existing protection schemes all use single-sensor, single-threshold judgment logic, lacking the ability to monitor the health status of the sensors themselves. Once the detection element experiences performance degradation or sudden failure, the system has no redundant backup or failure indication mechanism, and will directly enter the protection blind zone. At the same time, its recovery process after power failure usually relies on a simple one-time concentration re-detection, without setting differentiated reset verification conditions according to the severity of the triggered risk. In complex operating environments, there is a contradiction between too loose a reset leading to a second power failure, or too tight a reset affecting operating efficiency.

[0006] Therefore, how to design a hydrogen leak monitoring and power outage control system and method to enhance the adaptability to working conditions and long-term operational reliability in hydrogen-related mobile operation scenarios is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, the present invention provides a hydrogen leak monitoring and power-off control system and method, which aims to solve the problems of the separation of detection and power-off functions in existing protection schemes, the reliance on manual operation and the lag in response, and the impact of additional devices on the convenience of tool operation, so as to realize the real-time autonomous monitoring of hydrogen leaks by the tool body, accurate risk assessment and automatic disconnection of power supply circuit.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a hydrogen leak monitoring and power-off control system, integrated into the body of hydrogen-related work tools, comprising: The hydrogen detection and signal conditioning unit is used to acquire hydrogen concentration signals and convert them into analog voltage signals, as well as to linearly amplify and filter the analog voltage signals and output voltage signals with a standard range. The control unit, connected to the hydrogen detection and signal conditioning unit, is used to acquire and process the voltage signal of the standard range in real time and generate control commands. An execution unit is connected to the control unit and to the power supply circuit of the hydrogen-related work tool drive module, and is used to control the on / off state of the power supply circuit according to control commands. A manual reset unit, connected to the control unit, is used to input a reset trigger signal to the control unit in a power-off locked state; The voltage conversion unit is connected to the power module of the hydrogen-related work tool, and is also connected to the hydrogen detection and signal conditioning unit, control unit, execution unit and manual reset unit to provide a stable low-voltage working power supply.

[0010] Preferably, the hydrogen detection and signal conditioning unit includes a hydrogen sensing circuit U1, an operational amplifier circuit U2, resistors R1, R2, and R3, and a capacitor C1. In this circuit, the output terminal of the hydrogen sensing circuit U1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the non-inverting input terminal of the operational amplifier circuit U2 and one end of the filter capacitor C1, and the other end of the filter capacitor C1 is grounded. The inverting input of the operational amplifier circuit U2 is grounded through resistor R2, the inverting output is connected to the control unit, and a resistor R3 is connected between the inverting input and the inverting output.

[0011] Preferably, the control unit includes a microcontroller U3, a capacitor C3, and a capacitor C4; Among them, capacitors C3 and C4 are connected in parallel between the power supply pin and the ground pin of microcontroller U3.

[0012] Preferably, the execution unit includes a relay RELAY1, a MOSFET Q1, a resistor R5, a resistor R6, a resistor R7, and a diode D1; The source of the MOS transistor Q1 is connected to one end of resistor R6, the other end of resistor R6 is grounded and connected to one end of resistor R5, and the other end of resistor R5 is connected to the gate of the MOS transistor Q1 and connected to the control unit. The drain of the MOSFET Q1 is connected to one end of the resistor R7 and the coil of the relay RELAY1. The other end of the resistor R7 is connected to the diode D1 and to the other end of the coil of the relay RELAY1. The normally open / normally closed interface of the relay RELAY1 is connected in series in the power supply circuit of the hydrogen-related work tool to perform on / off control.

[0013] Preferably, the manual reset unit includes a self-reset switch KEY1, a resistor R4, and a capacitor C2; Among them, one end of resistor R4 is grounded, and the other end is connected to the control unit through a common node; there are two branches between the common node and the power supply, one branch is a direct wire connection, and the other branch is connected in parallel with capacitor C2, and the two branches are connected through self-reset switch KEY1.

[0014] Preferably, the voltage conversion unit includes a power management chip U4, capacitors C5, C6, C7, C8, C9, C10, and C11, resistors R7 and R8, and inductor L1. The power management chip U4 includes multiple ports, among which: A capacitor C5 is connected between the BS and SW interfaces; The SW interface is connected to one end of inductor L1, the VIN, SVIN, and EN interfaces are connected to one end of capacitor C6, the VIN interface is connected to one end of capacitor C10, the SS interface is connected to one end of capacitor C7, and the VCC interface is connected to one end of capacitor C8. The other ends of capacitors C6, C10, C7, and C8 are connected to one end of capacitor C11, and the other end of capacitor C11 is connected to the other end of inductor L1 and the power supply pin of the control unit. The FB interface connects to capacitor C9 and the series branch of resistors R7 and R8.

[0015] Secondly, the present invention provides a method for monitoring and controlling hydrogen leakage, comprising the following steps: The system powers on and performs hardware self-test and hydrogen sensor calibration. Once in monitoring mode, the processed hydrogen concentration signal is periodically acquired. ; Perform dual-channel leak detection: The first channel will transmit the hydrogen concentration signal. With danger threshold In comparison, if The first trigger signal is then generated; the second channel is based on the hydrogen concentration signal. Warning threshold Update the risk assessment index and cumulative trigger threshold In comparison, if Then a second trigger signal is generated; In response to the first trigger signal or the second trigger signal, the control unit sends a power-off command to the execution unit, which then cuts off the power supply circuit of the hydrogen-related work tool, and the system enters a power-off lockout state. In the power-off locked state, in response to the manual reset signal, verification is performed based on the adaptation reset verification conditions; if the verification passes, power is restored, otherwise the locked state is maintained.

[0016] Preferably, the updated risk assessment index Represented as:

[0017] in, Contribution to instantaneous risk, when hour, Otherwise, it is 0; Contribution to trend risk ; The current value, The previous value is given, and γ is the forgetting factor. The upper limit of the index is given by α, where α is the instantaneous risk coefficient and β is the trend risk coefficient. For the present The slope relative to the recent historical average.

[0018] Preferably, the dynamic adaptation reset verification conditions include: Based on the channel type of the power failure trigger signal, different continuous safety sampling number N and safety judgment threshold are set respectively. If the trigger signal comes from the first channel, the preset high-strictness level parameters are directly used; if the trigger signal comes from the second channel, the risk assessment index before triggering is applied. average growth rate Determine the corresponding parameters; During reset verification, the sampled values ​​must satisfy the requirements for N consecutive times. It passed in time.

[0019] Preferably, it also includes performing sensor health assessment and dynamically compensating for the judgment parameters, including: The signal-to-noise ratio H and baseline drift rate R are calculated as health indicators. When the health indicator suggests sensor performance degradation but no malfunction, the warning threshold will be adjusted to... And correct the cumulative trigger threshold to ; in, The compensation amount is determined based on the drift rate R. The attenuation factor is determined based on the noise ratio H.

[0020] As can be seen from the above technical solution, compared with the prior art, the technical solution of the present invention has the following beneficial effects: 1. This technical solution integrates hydrogen detection, signal conditioning, control judgment, and power-off execution units into the main body of hydrogen-related work tools, forming an independent functional module with autonomous monitoring and response capabilities. The control unit is directly connected to the execution unit through a hardware interface, and can automatically send a power-off command after detecting a leakage signal. The execution unit then physically cuts off the tool's power supply circuit without manual intervention. This forms a complete localized linkage response mechanism from signal acquisition to power cutoff, solving the problem of delayed response caused by the functional fragmentation and reliance on manual operation in existing protection solutions.

[0021] 2. The control method adopts a dual-channel parallel judgment architecture: the first channel realizes instantaneous triggering based on the danger threshold, and responds immediately to sudden high-concentration leaks; the second channel constructs a risk assessment index, integrates instantaneous concentration deviation and concentration change trend, and performs cumulative assessment and early warning triggering for low-concentration continuous leaks or abnormal concentration fluctuations. This architecture is compatible with both immediate protection and forward-looking early warning safety logic in the same system. While ensuring rapid response, it effectively suppresses malfunctions caused by transient interference, and achieves coordinated and unified risk classification perception and judgment capabilities.

[0022] 3. The system has the capability of online assessment and dynamic compensation of sensor health parameters. It can identify the sensor performance degradation state based on the signal noise level and baseline drift, and adaptively adjust the warning threshold and cumulative trigger threshold to maintain the effectiveness of the judgment logic. The reset verification conditions are dynamically adapted according to the power failure trigger channel type and historical risk trends to avoid the problem of overly strict or lenient verification under complex working conditions by a single reset logic. The above mechanisms enable the system to maintain stable monitoring and judgment capabilities under non-ideal working conditions such as sensor performance fluctuations and environmental interference, thereby improving the system's adaptability and reliability in mobile operation scenarios. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 This is a framework diagram of a hydrogen leak monitoring and power failure control system provided in an embodiment of the present invention; Figure 2 This is a flowchart of a hydrogen leak monitoring and power outage control method provided in an embodiment of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1; like Figure 1 As shown, this embodiment provides a hydrogen leak monitoring and power-off control system, including: The hydrogen detection and signal conditioning unit is used to acquire hydrogen concentration signals and convert them into analog voltage signals, as well as to linearly amplify and filter the analog voltage signals and output voltage signals with a standard range. The control unit, connected to the hydrogen detection and signal conditioning unit, is used to acquire and process the voltage signal of the standard range in real time and generate control commands. An execution unit is connected to the control unit and to the power supply circuit of the hydrogen-related work tool drive module, and is used to control the on / off state of the power supply circuit according to control commands. A manual reset unit, connected to the control unit, is used to input a reset trigger signal to the control unit in a power-off locked state; The voltage conversion unit is connected to the power module of the hydrogen-related work tool, and is also connected to the hydrogen detection and signal conditioning unit, control unit, execution unit and manual reset unit to provide a stable low-voltage working power supply.

[0027] Taking a handheld electric wrench used for hydrogen fuel cell maintenance as an example, the hydrogen leak monitoring and power-off control system can be integrated inside the tool body: the hydrogen detection and signal conditioning unit is installed on the tool head near the air inlet, and can be encapsulated in a waterproof and dustproof manner to prioritize the detection of leaking hydrogen; the control unit is located on the circuit board inside the handle, close to the battery pack to shorten the signal path; the relay in the execution unit is connected in series in the main power supply circuit between the battery pack and the motor drive module, and is located at the connection between the handle and the body to facilitate physical power-off; the manual reset unit is located near the handle gripping part, so that the operator can manually restore the power supply after confirming safety; the voltage conversion unit is located next to the battery pack interface to directly convert the tool power to the low voltage required by the system, reducing additional wiring; the units are connected by explosion-proof connectors and shielded cables, and the overall encapsulation meets the protection level of IP54 or higher, adapting to the vibration, dust and humidity environment in mobile operations.

[0028] The following provides a further detailed description of each unit in the above system; The hydrogen detection and signal conditioning unit in this embodiment is used to acquire hydrogen concentration signals and convert them into analog voltage signals, as well as to linearly amplify and filter the analog voltage signals and output a voltage signal with a standard range; specifically, it includes a hydrogen sensing circuit U1, an operational amplifier circuit U2, resistors R1, R2, R3 and capacitor C1. In this circuit, the output terminal of the hydrogen sensing circuit U1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the non-inverting input terminal of the operational amplifier circuit U2 and one end of the filter capacitor C1, and the other end of the filter capacitor C1 is grounded. The inverting input of the operational amplifier circuit U2 is grounded through resistor R2, the inverting output is connected to the control unit, and a resistor R3 is connected between the inverting input and the inverting output.

[0029] This unit converts hydrogen concentration into an analog voltage signal through a hydrogen sensing circuit, and then performs linear amplification and filtering through an operational amplifier circuit. Finally, it outputs a standard-range voltage signal to the control unit, thereby realizing the acquisition and conditioning of hydrogen leakage signals and ensuring the stability and accuracy of the detection signal.

[0030] The control unit in this embodiment is connected to the hydrogen detection and signal conditioning unit and is used to acquire and process the voltage signal of the standard range in real time to generate control commands; it includes a microcontroller U3, a capacitor C3, and a capacitor C4. Among them, capacitors C3 and C4 are connected in parallel between the power supply pin and the ground pin of microcontroller U3.

[0031] The control unit collects and processes standard voltage signals from the hydrogen detection and signal conditioning unit in real time, determines whether the hydrogen concentration exceeds the limit through a built-in algorithm, and generates corresponding control commands accordingly to achieve intelligent monitoring and decision-making on the system status.

[0032] The execution unit in this embodiment is connected to the control unit and to the power supply circuit of the hydrogen-related work tool drive module, and is used to control the on / off state of the power supply circuit according to the control command; it includes a relay RELAY1, a MOSFET Q1, a resistor R5, a resistor R6, a resistor R7 and a diode D1; The source of the MOS transistor Q1 is connected to one end of resistor R6, the other end of resistor R6 is grounded and connected to one end of resistor R5, and the other end of resistor R5 is connected to the gate of the MOS transistor Q1 and connected to the control unit. The drain of the MOSFET Q1 is connected to one end of the resistor R7 and the coil of the relay RELAY1. The other end of the resistor R7 is connected to the diode D1 and to the other end of the coil of the relay RELAY1. The normally open / normally closed interface of the relay RELAY1 is connected in series in the power supply circuit of the hydrogen-related work tool to perform on / off control.

[0033] The execution unit consists of a relay, a MOSFET, and related circuits. After receiving instructions from the control unit, it drives the relay through the MOSFET to directly control the on / off of the power supply circuit of the hydrogen-related work tool, thereby achieving physical power-off protection and ensuring that the power supply can be quickly cut off in the event of a leak.

[0034] The manual reset unit in this embodiment is connected to the control unit and is used to input a reset trigger signal to the control unit in the power-off locked state; it includes a self-reset switch KEY1, a resistor R4 and a capacitor C2. Among them, one end of resistor R4 is grounded, and the other end is connected to the control unit through a common node; there are two branches between the common node and the power supply, one branch is a direct wire connection, and the other branch is connected in parallel with capacitor C2, and the two branches are connected through self-reset switch KEY1.

[0035] It provides a manual reset function for the system through a self-reset switch and peripheral circuitry. In the power-off locked state, the user can input a reset trigger signal to the control unit by pressing the reset button, so that the system can be restarted after confirming that it is safe.

[0036] The voltage conversion unit in this embodiment is connected to the power module of the hydrogen-related work tool, and is also connected to the hydrogen detection and signal conditioning unit, control unit, execution unit and manual reset unit to provide a stable low-voltage working power supply; it includes a power management chip U4, capacitors C5, C6, C7, C8, C9, C10, C11, resistors R7 and R8 and inductor L1; The power management chip U4 includes multiple ports, among which: A capacitor C5 is connected between the BS and SW interfaces; The SW interface is connected to one end of inductor L1, the VIN, SVIN, and EN interfaces are connected to one end of capacitor C6, the VIN interface is connected to one end of capacitor C10, the SS interface is connected to one end of capacitor C7, and the VCC interface is connected to one end of capacitor C8. The other ends of capacitors C6, C10, C7, and C8 are connected to one end of capacitor C11, and the other end of capacitor C11 is connected to the other end of inductor L1 and the power supply pin of the control unit. The FB interface connects to capacitor C9 and the series branch of resistors R7 and R8.

[0037] This unit connects to the power module of the hydrogen-related work tool. Through the power management chip and multi-stage capacitors, inductors and other components, it converts the input power into stable low-voltage DC power, providing a reliable operating voltage for the entire system and ensuring that each unit operates normally in a mobile working environment.

[0038] The hydrogen leak monitoring and power-off control system in this embodiment integrates a hydrogen detection and signal conditioning unit, a control unit, an execution unit, a manual reset unit, and a voltage conversion unit into a single hardware design. This design creates a complete closed-loop circuit for leak monitoring and automatic power-off within the hydrogen-related work tool. The operational amplifier circuit, in conjunction with current-limiting resistors and filter capacitors, achieves linear amplification and anti-interference conditioning of weak signals. A MOSFET-driven relay, along with normally closed contacts, forms a physical hard-cutoff path. A self-reset button and a pull-up input pin create a dedicated reset interface that operates only in the power-off locked state. The voltage conversion unit directly utilizes the tool's built-in power supply for multi-stage step-down and voltage regulation. Its overall structure is compact and can be directly embedded into existing power tools without significant modifications, demonstrating excellent engineering feasibility and adaptability to mobile work environments.

[0039] Example 2; like Figure 2 As shown, this embodiment provides a method for monitoring and controlling hydrogen leaks and power outages, including the following steps: The system powers on and performs hardware self-test and hydrogen sensor calibration. Once in monitoring mode, the processed hydrogen concentration signal is periodically acquired. ; Perform dual-channel leak detection: The first channel will transmit the hydrogen concentration signal. With danger threshold In comparison, if The first trigger signal is then generated; the second channel is based on the hydrogen concentration signal. Warning threshold Update the risk assessment index and cumulative trigger threshold In comparison, if Then a second trigger signal is generated; In response to the first trigger signal or the second trigger signal, the control unit sends a power-off command to the execution unit, which then cuts off the power supply circuit of the hydrogen-related work tool, and the system enters a power-off lockout state. In the power-off locked state, in response to the manual reset signal, verification is performed based on the adaptation reset verification conditions; if the verification passes, power is restored, otherwise the locked state is maintained.

[0040] Furthermore, the updated risk assessment index Represented as:

[0041] in, Contribution to instantaneous risk, when hour, Otherwise, it is 0; Contribution to trend risk ; The current value, The previous value is given, and γ is the forgetting factor. The upper limit of the index is given by α, where α is the instantaneous risk coefficient and β is the trend risk coefficient. For the present The slope relative to the recent historical average.

[0042] Furthermore, the dynamic adaptation reset verification conditions include: Based on the channel type of the power failure trigger signal, different continuous safety sampling number N and safety judgment threshold are set respectively. If the trigger signal comes from the first channel, the preset high-strictness level parameters are directly used; if the trigger signal comes from the second channel, the risk assessment index before triggering is applied. average growth rate Determine the corresponding parameters; Specifically, if the power outage is triggered by the first channel, a high-level verification parameter is used: the number of consecutive safe samplings. Safety threshold ; The preset number of high-strictness sampling times, This is the preset high-strictness threshold offset; if the power outage is triggered by the second channel, then it is based on the value before the trigger. average growth rate Calculate the verification parameters: number of samples Safety threshold ; and The default baseline stringency level parameters are λ and μ, which are default scaling factors. Indicates rounding down; During reset verification, the sampled values ​​must satisfy the requirements for N consecutive times. It passed in time.

[0043] Furthermore, it also includes conducting sensor health assessments and dynamically compensating for judgment parameters, including: The signal-to-noise ratio H and baseline drift rate R are calculated as health indicators. When the health indicator suggests sensor performance degradation but no malfunction, the warning threshold will be adjusted to... And correct the cumulative trigger threshold to ; in, The compensation amount is determined based on the drift rate R. The attenuation factor is determined based on the noise ratio H.

[0044] This embodiment uses a dual-channel parallel judgment architecture. On the basis of the immediate triggering of the danger threshold, a second channel based on the accumulation of risk assessment index is introduced to quantify the concentration amplitude, duration and change trend into index increments, so as to realize continuous tracking and graded early warning of non-instantaneous excessive leakage. In the power-off lockout state, the number of sampling and safety thresholds for reset verification are dynamically adapted according to the trigger channel type and historical risk trend, and different recovery severity levels correspond to different leakage severity levels. Meanwhile, by continuously monitoring the signal-to-noise ratio and baseline drift rate, the warning threshold and trigger threshold are dynamically compensated during the sensor performance degradation stage, so that the system maintains a relatively stable judgment sensitivity throughout its entire life cycle, reducing the risk of false alarms and missed alarms caused by device aging or environmental disturbances.

[0045] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0046] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydrogen leak monitoring and power-off control system, characterized in that, Integrated into the main body of hydrogen-related work tools, including: The hydrogen detection and signal conditioning unit is used to acquire hydrogen concentration signals and convert them into analog voltage signals, as well as to linearly amplify and filter the analog voltage signals and output voltage signals with a standard range. The control unit, connected to the hydrogen detection and signal conditioning unit, is used to acquire and process the voltage signal of the standard range in real time and generate control commands. An execution unit is connected to the control unit and to the power supply circuit of the hydrogen-related work tool drive module, and is used to control the on / off state of the power supply circuit according to control commands. A manual reset unit, connected to the control unit, is used to input a reset trigger signal to the control unit in a power-off locked state; The voltage conversion unit is connected to the power module of the hydrogen-related work tool, and is also connected to the hydrogen detection and signal conditioning unit, control unit, execution unit and manual reset unit to provide a stable low-voltage working power supply.

2. The hydrogen leak monitoring and power-off control system according to claim 1, characterized in that, The hydrogen detection and signal conditioning unit includes a hydrogen sensing circuit U1, an operational amplifier circuit U2, resistors R1, R2, and R3, and a capacitor C1. In this circuit, the output terminal of the hydrogen sensing circuit U1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the non-inverting input terminal of the operational amplifier circuit U2 and one end of the filter capacitor C1, and the other end of the filter capacitor C1 is grounded. The inverting input of the operational amplifier circuit U2 is grounded through resistor R2, the inverting output is connected to the control unit, and a resistor R3 is connected between the inverting input and the inverting output.

3. The hydrogen leak monitoring and power-off control system according to claim 1, characterized in that, The control unit includes a microcontroller U3, a capacitor C3, and a capacitor C4; Among them, capacitors C3 and C4 are connected in parallel between the power supply pin and the ground pin of microcontroller U3.

4. The hydrogen leak monitoring and power-off control system according to claim 1, characterized in that, The execution unit includes a relay RELAY1, a MOSFET Q1, a resistor R5, a resistor R6, a resistor R7, and a diode D1; The source of the MOS transistor Q1 is connected to one end of resistor R6, the other end of resistor R6 is grounded and connected to one end of resistor R5, and the other end of resistor R5 is connected to the gate of the MOS transistor Q1 and connected to the control unit. The drain of the MOSFET Q1 is connected to one end of the resistor R7 and the coil of the relay RELAY1. The other end of the resistor R7 is connected to the diode D1 and to the other end of the coil of the relay RELAY1. The normally open / normally closed interface of the relay RELAY1 is connected in series in the power supply circuit of the hydrogen-related work tool to perform on / off control.

5. The hydrogen leak monitoring and power-off control system according to claim 1, characterized in that, The manual reset unit includes a self-reset switch KEY1, a resistor R4, and a capacitor C2; Among them, one end of resistor R4 is grounded, and the other end is connected to the control unit through a common node; there are two branches between the common node and the power supply, one branch is a direct wire connection, and the other branch is connected in parallel with capacitor C2, and the two branches are connected through self-reset switch KEY1.

6. The hydrogen leak monitoring and power-off control system according to claim 1, characterized in that, The voltage conversion unit includes a power management chip U4, capacitors C5, C6, C7, C8, C9, C10, and C11, resistors R7 and R8, and inductor L1. The power management chip U4 includes multiple ports, among which: A capacitor C5 is connected between the BS and SW interfaces; The SW interface is connected to one end of inductor L1, the VIN, SVIN, and EN interfaces are connected to one end of capacitor C6, the VIN interface is connected to one end of capacitor C10, the SS interface is connected to one end of capacitor C7, and the VCC interface is connected to one end of capacitor C8. The other ends of capacitors C6, C10, C7, and C8 are connected to one end of capacitor C11, and the other end of capacitor C11 is connected to the other end of inductor L1 and the power supply pin of the control unit. The FB interface connects to capacitor C9 and the series branch of resistors R7 and R8.

7. A method for monitoring and controlling hydrogen leaks, characterized in that, Includes the following steps: The system powers on and performs hardware self-test and hydrogen sensor calibration. Once in monitoring mode, the processed hydrogen concentration signal is periodically acquired. ; Perform dual-channel leak detection: The first channel will transmit the hydrogen concentration signal. With danger threshold In comparison, if Then the first trigger signal is generated; The second channel is based on the hydrogen concentration signal. Warning threshold Update the risk assessment index and cumulative trigger threshold In comparison, if Then a second trigger signal is generated; In response to the first trigger signal or the second trigger signal, the control unit sends a power-off command to the execution unit, which then cuts off the power supply circuit of the hydrogen-related work tool, and the system enters a power-off lockout state. In the power-off locked state, in response to the manual reset signal, verification is performed based on the adaptation reset verification conditions; if the verification passes, power is restored, otherwise the locked state is maintained.

8. The hydrogen leak monitoring and power outage control method according to claim 7, characterized in that, The updated risk assessment index Represented as: in, Contribution to instantaneous risk, when hour, Otherwise, it is 0; Contribution to trend risk ; The current value, The previous value is given, and γ is the forgetting factor. The upper limit of the index is given by α, where α is the instantaneous risk coefficient and β is the trend risk coefficient. For the present The slope relative to the recent historical average.

9. The hydrogen leak monitoring and power outage control method according to claim 7, characterized in that, The dynamic adaptation reset verification conditions include: Based on the channel type of the power failure trigger signal, different continuous safety sampling number N and safety judgment threshold are set respectively. If the trigger signal comes from the first channel, the preset high-strictness level parameters are directly used; if the trigger signal comes from the second channel, the risk assessment index before triggering is applied. average growth rate Determine the corresponding parameters; During reset verification, the sampled values ​​must satisfy the requirements for N consecutive times. It passed in time.

10. The hydrogen leak monitoring and power-off control method according to claim 7, characterized in that, This also includes conducting sensor health assessments and dynamically compensating for judgment parameters, including: The signal-to-noise ratio H and baseline drift rate R are calculated as health indicators. When the health indicator suggests sensor performance degradation but no malfunction, the warning threshold will be adjusted to... And correct the cumulative trigger threshold to ; in, The compensation amount is determined based on the drift rate R. The attenuation factor is determined based on the noise ratio H.

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