Hydrogen leakage alarm system for hydrogen power driving equipment

Abstract

The invention discloses a hydrogen leakage alarm system for hydrogen power driving equipment, which adopts a hydrogen sensitive element based on an electrochemical principle, and because the intrinsic reaction speed of the hydrogen sensitive element is far higher than that of a traditional semiconductor sensor, early leakage early warning can be realized, and the response speed is improved; the MCU adjusts the heating power of the heating element based on the environment temperature and a preset temperature control algorithm so as to control the heating temperature of the heating element, so that the MCU can dynamically adjust the heating power applied to the heating element according to the environment temperature fed back by the temperature sensor instead of continuous full-power heating, and the power consumption is greatly reduced; according to the technical scheme of the invention, the alarm counter is subjected to integral judgment instead of single-point instantaneous judgment, so that only continuously existing leakage signals can enable the alarm counter to accumulate to the alarm triggering level, transient environmental interference or random noise is effectively filtered out, the anti-interference capability and reliability are improved, and the occurrence of false alarm or missing alarm is reduced.

Description

Technical Field

[0001] This invention relates to the field of hydrogen alarm technology, and more specifically, to a hydrogen leak alarm system for hydrogen-powered vehicles. Background Technology

[0002] With the rapid development of the hydrogen energy industry, hydrogen-powered vehicles, as a green driving tool, are gradually entering the market. However, hydrogen is flammable and explosive, with an explosive limit of 4%-75% in air. This means that hydrogen-powered vehicles may leak hydrogen during driving or parking due to aging pipelines, loose joints, or accidental impacts, posing a serious safety hazard.

[0003] Currently, the main methods for detecting hydrogen leaks in hydrogen-powered vehicles are as follows: Hydrogen sensors based on semiconductor principles detect concentration by detecting changes in the resistance of a metal-oxide-semiconductor system caused by hydrogen gas. Their advantages include low cost, but they typically suffer from drawbacks such as slow response time, long recovery time, susceptibility to environmental temperature and humidity fluctuations, and high power consumption.

[0004] Hydrogen sensors based on the catalytic combustion principle are commonly used for industrial safety monitoring. They offer high detection accuracy within the lower explosive limit concentration range, but require continuous operation at high temperatures, resulting in extremely high power consumption. They are also sensitive to catalyst poisoning, making them unsuitable for long-term use in hydrogen-powered vehicles with stringent limitations on power consumption and size.

[0005] Sensors based on the near-field sensing principle detect targets by detecting changes in physical fields such as electric and acoustic fields. However, when directly applied to the specific detection of hydrogen leaks in moving, vibrating, and space-constrained hydrogen-powered vehicles, they suffer from problems such as weak anti-interference capabilities, high false alarm rates in complex vehicle environments, and increased costs due to the need for complex signal processing circuits.

[0006] In summary, existing hydrogen leak alarm methods have the following drawbacks: Response speed: The sensor takes a long time from contact with hydrogen to outputting a stable signal, which cannot meet the requirements for early warning of rapid leaks.

[0007] High power consumption: Hydrogen sensors based on the catalytic combustion principle and some semiconductor sensors require continuous or frequent heating, resulting in high power consumption and severely impacting the limited driving range of hydrogen-powered vehicles.

[0008] Poor environmental adaptability: Hydrogen-powered vehicles operate in environments with large temperature differences and strong vibrations. Existing sensors are easily affected by these factors, resulting in poor stability, false alarms, or missed alarms. Summary of the Invention

[0009] This invention provides a hydrogen leak alarm system for hydrogen-powered vehicles, which improves response speed, reduces power consumption, and decreases the occurrence of false alarms or missed alarms. The specific technical solution is as follows.

[0010] In a first aspect, the present invention provides a hydrogen leak alarm system for a hydrogen-powered driving device, including a temperature sensor, a hydrogen sensor, a microcontroller unit (MCU) with a built-in analog-to-digital converter (ADC) and an audible and visual alarm device installed in the frame of the hydrogen-powered driving device. The hydrogen sensor includes a hydrogen-sensitive element, a low-power operational amplifier and a heating element. The hydrogen-sensitive element is connected to the low-power operational amplifier. The temperature sensor, the low-power operational amplifier, the heating element, and the audible and visual alarm device are all connected to the MCU. The hydrogen-sensitive element is located near the gas valve of the hydrogen storage tank of the hydrogen-powered driving device. The temperature sensor sends the detected ambient temperature inside the rack to the MCU; The MCU adjusts the heating power of the heating element based on the ambient temperature and a preset temperature control algorithm to control the heating temperature of the heating element; The hydrogen-sensitive element sends the detected voltage signal to the low-power operational amplifier; The low-power operational amplifier performs signal following processing on the voltage signal to obtain a processed voltage signal, and sends it to the MCU; The MCU determines compensation parameters based on the ambient temperature, determines compensation values ​​based on the compensation parameters and the processed voltage signal, determines a compensated voltage signal based on the compensation value and the processed voltage signal, and determines whether the compensated voltage signal exceeds the target alarm threshold. If it does, the value of the alarm counter is increased by a preset value, and the audible and visual alarm device is controlled to sound an alarm based on the increased value. The target alarm threshold is calculated based on the sum of a first voltage signal at a first ratio and a second voltage signal at a second ratio. The sum of the first ratio and the second ratio is 1, and the first ratio is less than the second ratio.

[0011] Optionally, the hydrogen sensor may also include a circuit board (PCB), a multi-core cable, and a waterproof connector. The hydrogen-sensitive element, the low-power operational amplifier, and the heating element are all mounted on the PCB board, which is fixed in the mounting holes of the frame. The low-power operational amplifier is signal-connected to one end of the multi-core cable, and the other end of the multi-core cable is provided with the waterproof connector. The waterproof connector is pluggably connected to the MCU. The mounting hole is close to the gas valve of the hydrogen storage tank of the hydrogen-powered driving device.

[0012] Optionally, the MCU is also used to determine whether the ambient temperature exceeds a preset temperature threshold. If so, the heating power of the heating element is reduced to the power corresponding to the ambient temperature.

[0013] Optionally, the MCU is also connected to the controller signal of the hydrogen-powered driving device. The MCU is also used to determine whether it receives a start signal sent by the controller. If so, it adjusts the heating power of the heating element to the rated frequency.

[0014] Optionally, the MCU determines whether the increased value is greater than the third-level alarm threshold. If it is greater than the third-level alarm threshold, it controls the hydrogen energy conversion power system of the hydrogen-powered driving device to cut off power and controls the audible and visual alarm device to activate the audible and visual alarm. If it is not greater than the third-level alarm threshold, it determines whether the increased value is greater than the second-level alarm threshold. If it is greater than the second-level alarm threshold, it controls the output power of the motor of the hydrogen energy conversion power system to be reduced to half of the rated power and controls the audible and visual alarm device to activate the audible and visual alarm. If it is not greater than the second-level alarm threshold, it determines whether the increased value is greater than the first-level alarm threshold. If it is greater than the first-level alarm threshold, it controls the display of the hydrogen-powered driving device to issue a warning and controls the alarm light of the audible and visual alarm device to flash.

[0015] Optionally, the MCU determines the compensation parameters based on the correspondence between the ambient temperature and the pre-stored temperature and compensation parameters, calculates the difference between the processed voltage signal and the compensation parameters as the compensation value, and calculates the sum of the compensation value and the processed voltage signal as the compensated voltage signal.

[0016] Optionally, the first voltage signal is the minimum value of the voltage signals detected by the hydrogen-sensitive element when there was no hydrogen leakage during the last hydrogen leak detection, and the second voltage signal is the voltage signal detected by the hydrogen-sensitive element when the air contains 4% hydrogen.

[0017] Optionally, the MCU is further configured to determine that the processed voltage signal does not exceed the target alarm threshold, reduce the value of the alarm counter by the preset value, and return to execute the MCU to adjust the heating power of the heating element based on the ambient temperature and the preset temperature control algorithm to control the heating temperature of the heating element.

[0018] Optionally, the MCU is also used to, after controlling the power outage of the hydrogen energy conversion power system of the hydrogen-powered driving device and controlling the audible and visual alarm device to perform an audible and visual alarm, after receiving a reset signal, to supply power to the hydrogen energy conversion power system and return to execute the MCU to adjust the heating power of the heating element based on the ambient temperature and the preset temperature control algorithm to control the heating temperature of the heating element.

[0019] Optionally, the MCU is also used to control the heating element's heating power to control its heating temperature after controlling the output power of the motor of the hydrogen energy conversion power system to be reduced to half of the rated power, and after controlling the audible and visual alarm device to issue an audible and visual alarm, or after controlling the display of the hydrogen-powered driving device to issue a warning and controlling the alarm light of the audible and visual alarm device to flash.

[0020] As described above, the hydrogen leak alarm system for hydrogen-powered driving equipment provided in this embodiment of the invention includes a temperature sensor, a hydrogen sensor, an MCU with a built-in digital-to-analog converter (ADC), and an audible and visual alarm device installed within the frame of the hydrogen-powered driving equipment. The hydrogen sensor includes a hydrogen-sensitive element, a low-power operational amplifier, and a heating element. The hydrogen-sensitive element is signal-connected to the low-power operational amplifier, while the temperature sensor, low-power operational amplifier, heating element, and audible and visual alarm device are all signal-connected to the MCU. The hydrogen sensor is located near the gas valve of the hydrogen storage tank in the hydrogen-powered driving equipment. The temperature sensor sends the detected ambient temperature within the frame to the MCU. The MCU adjusts the heating power of the heating element based on the ambient temperature and a preset temperature control algorithm to control the heating of the heating element. The system detects a voltage signal from a hydrogen-sensitive element and sends it to a low-power operational amplifier. The low-power operational amplifier performs signal following processing on the voltage signal to obtain a processed voltage signal, which is then sent to the MCU. The MCU determines compensation parameters based on the ambient temperature, determines a compensation value based on the compensation parameters and the processed voltage signal, determines a compensated voltage signal based on the compensation value and the processed voltage signal, and determines whether the compensated voltage signal exceeds the target alarm threshold. If it does, the alarm counter value is increased by a preset value, and the audible and visual alarm device is controlled to sound an alarm based on the increased value. The target alarm threshold is calculated based on the sum of a first voltage signal at a first ratio and a second voltage signal at a second ratio. The sum of the first ratio and the second ratio is 1, and the first ratio is less than the second ratio. Therefore, by employing a hydrogen-sensitive element based on electrochemical principles, which has a much faster intrinsic reaction speed than traditional semiconductor sensors, early leakage warning can be achieved, improving response speed. Furthermore, the MCU adjusts the heating power of the heating element based on ambient temperature and a preset temperature control algorithm to control the heating temperature. This allows the MCU to dynamically adjust the heating power applied to the heating element based on the ambient temperature feedback from the temperature sensor, rather than continuously heating at full power, significantly reducing power consumption. By using an integral judgment method for the alarm counter instead of a single-point instantaneous judgment method, only a continuously existing leakage signal can cause the alarm counter to accumulate to the level that triggers an alarm. This effectively filters out transient environmental interference or random noise, greatly improving anti-interference capability and reliability, and reducing the occurrence of false alarms or missed alarms.

[0021] The innovative aspects of this invention include: 1. Employing a hydrogen-sensitive element based on electrochemical principles, which boasts an intrinsic reaction speed far exceeding that of traditional semiconductor sensors, early leakage warning is achieved, improving response speed. Furthermore, the MCU adjusts the heating power of the heating element based on ambient temperature and a preset temperature control algorithm to control its heating temperature. This allows the MCU to dynamically adjust the heating power applied to the heating element based on the ambient temperature feedback from the temperature sensor, rather than continuously heating at full power, significantly reducing power consumption. By using an integral judgment method for the alarm counter instead of a single-point instantaneous judgment, only a continuously existing leakage signal can cause the alarm counter to accumulate to the level that triggers an alarm. This effectively filters out transient environmental interference or random noise, greatly improving anti-interference capability and reliability, and reducing the occurrence of false alarms or missed alarms.

[0022] 2. By mounting the hydrogen-sensitive element, low-power operational amplifier, and heating element on the PCB board, which is then fixed in the mounting holes of the rack, the hydrogen sensor can be installed simply by opening holes in the rack, without the need for additional brackets. This makes installation convenient. Furthermore, the waterproof connector allows for pluggable connection to the MCU without the need for intermediate plugs, reducing the risk of poor contact and simplifying the structure, thus lowering costs.

[0023] 3. When the MCU determines that the ambient temperature exceeds the preset temperature threshold, it reduces the heating temperature by lowering the heating power of the heating element to the power corresponding to the ambient temperature. Compared with constant temperature heating, this can reduce power consumption.

[0024] 4. When the MCU receives the start signal sent by the controller, it performs rapid preheating by adjusting the heating power of the heating element to the rated frequency.

[0025] 5. The low-power operational amplifier consists of only a first resistor, a feedback resistor, and the operational amplifier, which simplifies the circuit while still achieving the function of signal following the voltage signal, thus reducing power consumption.

[0026] 6. The compensation parameters are determined based on the ambient temperature, and then the compensation value is calculated using the compensation parameters. The processed voltage signal is compensated using the compensation value. This takes into account the influence of ambient temperature on the voltage signal, which can improve the anti-interference ability, improve the stability and accuracy of the signal, reduce the probability of false alarms and missed alarms, and improve reliability.

[0027] 7. In the embodiments of the present invention, the setting of the target alarm threshold is equivalent to setting a buffer zone between the background noise and the clear alarm signal. Compared with the method of directly setting the target alarm threshold as the second voltage signal, it avoids false alarms caused by small fluctuations. Compared with the method of setting the target alarm threshold as the background noise, i.e. the first voltage signal, it can detect the leakage trend earlier and realize early warning.

[0028] 8. By setting the first voltage signal in the target alarm threshold to the minimum value of the voltage signal detected by the hydrogen-sensitive element when there was no hydrogen leak during the last hydrogen leak detection, instead of the voltage signal detected this time, the target alarm threshold is reduced, the situation of setting a high target alarm threshold due to aging is reduced, and the leakage trend is detected earlier to avoid danger.

[0029] 9. A three-tiered, progressive multi-level alarm strategy, from warnings to traffic restrictions and finally to protective power cut-off, provides riders with progressively escalating response times and clear coping guidelines, balancing safety and user experience.

[0030] Of course, implementing any product or method of the present invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0032] Figure 1 A schematic diagram of a hydrogen leak alarm system for hydrogen-powered driving equipment provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the circuit structure of a hydrogen sensor provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the T90 response time of a hydrogen-sensitive element.

[0033] Figures 1-3 The components include: 1. Temperature sensor; 2. Hydrogen sensor; 21. Hydrogen-sensitive element; 22. Low-power operational amplifier; 221. First resistor; 222. Feedback resistor; 223. Operational amplifier; 23. Heating element; 3. MCU; 4. Audible and visual alarm device; 5. Hydrogen storage tank; 6. Power supply; 10. Rack. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0035] It should be noted that the terms "comprising" and "having," and any variations thereof, in the embodiments and drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0036] This invention discloses a hydrogen leak alarm system for hydrogen-powered vehicles, which improves response speed, reduces power consumption, and minimizes false alarms or missed alarms. The embodiments of this invention are described in detail below.

[0037] Figure 1 This is a schematic diagram of a hydrogen leak alarm system for a hydrogen-powered vehicle provided in an embodiment of the present invention. (See also...) Figure 1 The hydrogen leak alarm system for hydrogen-powered driving equipment provided in this embodiment of the invention includes a temperature sensor 1, a hydrogen sensor 2, an MCU (Micro Controller Unit) 3 with built-in ADC (Analogue To Digital Conversion), and an audible and visual alarm device 4, all installed in the frame 10 of the hydrogen-powered driving equipment.

[0038] Figure 2 This is a schematic diagram of the circuit structure of the hydrogen sensor 2 provided in an embodiment of the present invention. See also... Figure 2 The hydrogen sensor 2 includes a hydrogen-sensitive element 21, a low-power operational amplifier 22, and a heating element 23. The hydrogen-sensitive element 21 is signal-connected to the low-power operational amplifier 22. The hydrogen-sensitive element 21 can be a tin dioxide metal oxide semiconductor or a palladium metal oxide semiconductor.

[0039] The working mechanism of the hydrogen-sensitive element 21 is that hydrogen gas undergoes an electrochemical reaction on the hydrogen-sensitive element 21, generating an electrical signal, i.e., voltage, that is proportional to the hydrogen concentration. Because this reaction is electrochemical, it has the characteristic of intrinsically fast response speed.

[0040] Figure 3 A schematic diagram showing the T90 response time of the hydrogen-sensitive element 21 is provided. Figure 3The vertical line on the left represents the voltage value detected by the hydrogen sensor 21 when there is no hydrogen leak. The vertical line on the right represents the voltage value detected by the hydrogen sensor 21 when the leaked hydrogen reaches the target alarm threshold. It can be seen that the target alarm threshold is reached before 36 seconds, starting from 35 seconds. Here, the target alarm threshold is set to the value corresponding to a 90% saturation signal. This shows that the T90 response time of the hydrogen sensor 21 can be shortened to less than 1 second, far faster than the T90 response time of traditional semiconductor sensors, which is typically >30 seconds, enabling rapid detection of hydrogen leaks. The T90 response time is the time required to reach a 90% saturation signal. Figure 3 The horizontal axis represents time, and the vertical axis represents voltage.

[0041] In one implementation, the hydrogen sensor 2 also includes a PCB (Printed Circuit Board), a multi-core cable, and a waterproof connector.

[0042] The hydrogen-sensitive element 21, the low-power operational amplifier 22, and the heating element 23 are all mounted on the PCB board, which is fixed in the mounting holes of the frame 10. The low-power operational amplifier 22 is connected to one end of a multi-core cable for signal transmission. The other end of the multi-core cable is equipped with a waterproof connector, which is pluggable to the MCU3. The mounting hole is located near the gas valve of the hydrogen storage tank of the hydrogen-powered vehicle.

[0043] To facilitate installation and reduce costs, this invention abandons the traditional separate housing and connector approach, and instead adopts a direct PCB board connection method. The PCB board can be secured to the mounting holes using clips or cable ties.

[0044] Therefore, by mounting the hydrogen-sensitive element 21, the low-power operational amplifier 22, and the heating element 23 on the PCB board, and fixing the PCB board in the mounting holes of the rack 10, the hydrogen-sensitive sensor 2 can be installed simply by opening holes in the rack, without the need for additional brackets, making installation convenient. At the same time, it can be plugged into the MCU 3 through a waterproof connector, without the need for intermediate plugs, reducing the risk of poor contact, simplifying the structure, and reducing costs.

[0045] See also Figure 1 and Figure 2 Temperature sensor 1, low-power operational amplifier 22, heating element 23 and audible and visual alarm device 4 are all connected to MCU3. Hydrogen sensor 2 is located near the gas valve of hydrogen storage tank 5 of hydrogen-powered driving equipment. Specifically, hydrogen sensing element 21 is located near the gas valve of hydrogen storage tank 5 of hydrogen-powered driving equipment.

[0046] In another implementation, the hydrogen sensor 2 also includes an I / O (Input / Output) converter. A low-power operational amplifier 22 is connected to the I / O converter, which in turn is connected to the MCU 3. This enables data exchange between the low-power operational amplifier 22 and the MCU 3.

[0047] During operation, temperature sensor 1 sends the detected ambient temperature inside rack 10 to MCU3.

[0048] Since the hydrogen-sensitive element 21 typically needs to operate at a specific temperature to achieve optimal performance and stability, traditional heating circuits employ continuous constant-temperature heating, resulting in high power consumption. This embodiment of the invention optimizes this process by having the MCU3 adjust the heating power of the heating element 23 based on the ambient temperature and a preset temperature control algorithm to control its heating temperature. This allows the MCU3 to dynamically adjust the heating power applied to the heating element 3 based on the ambient temperature feedback from the temperature sensor 1, rather than continuously heating at full power, thus reducing power consumption by more than 30%.

[0049] The preset temperature control algorithm can be a PWM (Pulse Width Modulation) algorithm, a fuzzy control algorithm, or a PID (Proportional Integral Derivative) control algorithm.

[0050] Specifically, the way MCU3 adjusts the heating power of heating element 23 based on ambient temperature and a preset temperature control algorithm to control the heating temperature of heating element 23 can be as follows: MCU3 is also used to determine whether the ambient temperature exceeds the preset temperature threshold. If so, it means that the ambient temperature is too high. At this time, the heating power of the heating element 23 can be reduced to the power corresponding to the ambient temperature.

[0051] Therefore, when MCU3 determines that the ambient temperature exceeds the preset temperature threshold, it reduces the heating temperature by lowering the heating power of heating element 23 to the power corresponding to the ambient temperature. Compared with constant temperature heating, this can reduce power consumption.

[0052] In one implementation, when the vehicle is stationary, MCU3 can also control the heating element 23 to pause heating in order to reduce power consumption.

[0053] In another implementation, MCU3 is also connected to the controller signal of the hydrogen-powered driving device. MCU3 is also used to determine whether it has received a start signal from the controller. If so, it means that the hydrogen-powered driving device is in a cold start. At this time, the heating power of the heating element 23 is adjusted to the rated frequency for rapid preheating.

[0054] Therefore, when the MCU3 receives the start signal sent by the controller, it performs rapid preheating by adjusting the heating power of the heating element 23 to the rated frequency.

[0055] Once a suitable temperature is reached, the hydrogen-sensitive element 21 sends the detected voltage signal to the low-power operational amplifier 22. The low-power operational amplifier 22 performs signal following processing on the voltage signal to obtain a processed voltage signal, which is then sent to the MCU3. Using the low-power operational amplifier 22 to perform signal following processing on the voltage signal improves anti-interference capability.

[0056] See also Figure 2 The low-power operational amplifier 22 includes a first resistor 221, a feedback resistor 222, and an operational amplifier 223. One end of the first resistor 221 is connected to the power supply 6, and the other end of the first resistor 221 is connected to the non-inverting input terminal of the operational amplifier 223 and one end of the feedback resistor 222. The other end of the feedback resistor 222 is grounded. The inverting input terminal and the output terminal of the operational amplifier 223 are both connected to the MCU3.

[0057] Therefore, the low-power operational amplifier 22 is configured to include only the first resistor 221, the feedback resistor 222, and the operational amplifier 223, which simplifies the circuit while still achieving the function of signal following processing of the voltage signal, thus reducing power consumption.

[0058] After receiving the processed voltage signal, MCU3 determines the compensation parameters based on the ambient temperature, determines the compensation value based on the compensation parameters and the processed voltage signal, and determines the compensated voltage signal based on the compensation value and the processed voltage signal.

[0059] Specifically, the memory stores a correspondence table between temperature and compensation parameters. The MCU3 determines the compensation parameters based on the ambient temperature and the pre-stored correspondence table, calculates the difference between the processed voltage signal and the compensation parameters as the compensation value, and calculates the sum of the compensation value and the processed voltage signal as the compensated voltage signal.

[0060] Therefore, compensation parameters are determined based on ambient temperature, and then compensation values ​​are calculated using these parameters. The processed voltage signal is then compensated using these compensation values. This approach takes into account the influence of ambient temperature on the voltage signal, thereby improving anti-interference capability, signal stability and accuracy, reducing the probability of false alarms and missed alarms, and enhancing reliability.

[0061] After obtaining the compensated voltage signal, MCU3 determines whether the compensated voltage signal exceeds the target alarm threshold. If it does, it increases the value of the alarm counter by a preset value and controls the audible and visual alarm device 4 to sound an alarm based on the increased value. The target alarm threshold is calculated based on the sum of the first voltage signal at a first ratio and the second voltage signal at a second ratio. The sum of the first ratio and the second ratio is 1, and the first ratio is less than the second ratio.

[0062] To improve anti-interference capability and reliability, this embodiment of the invention replaces single-point instantaneous judgment with integral judgment. Specifically, MCU3 judges whether the compensated voltage signal exceeds the target alarm threshold. If it does, the value of the alarm counter is increased by a preset value. To prevent the alarm counter from overflowing and to ensure that the hydrogen-powered driving device can automatically return to normal after the interference disappears, the upper limit of the alarm counter is set to 50000ms and the lower limit is 0. The preset value can be 1s.

[0063] An increase in the alarm counter indicates that the confidence level of a "suspected leak" is accumulating. Therefore, the audible and visual alarm device can be controlled to sound an alarm based on the increased value.

[0064] In one implementation, the target alarm threshold is calculated based on the sum of a first voltage signal at a first ratio and a second voltage signal at a second ratio; Wherein, the sum of the first ratio and the second ratio is 1, and the first ratio is less than the second ratio. The first voltage signal is the minimum value of the voltage signal detected by the hydrogen-sensitive element 21 when hydrogen leakage was not detected during the last hydrogen leak detection. The second voltage signal is the voltage signal detected by the hydrogen-sensitive element 21 when the air contains 4% hydrogen.

[0065] Specifically, the formula for the target alarm threshold can be: Target alarm threshold = (first proportion × first voltage signal) + (second proportion × second voltage signal) For example, the first ratio can be 1 / 3 and the second ratio can be 2 / 3.

[0066] In this embodiment of the invention, the setting of the target alarm threshold is equivalent to setting a buffer zone between the background noise and the explicit alarm signal. Compared with the method of directly setting the target alarm threshold as the second voltage signal, it avoids false alarms caused by small fluctuations. Moreover, compared with the method of setting the target alarm threshold as the background noise, i.e. the first voltage signal, it can detect the leakage trend earlier and achieve early warning.

[0067] Over time, the hydrogen sensor 2 will age with prolonged use, leading to an overestimation of the detected voltage signal and inaccurate detection. In this embodiment of the invention, by setting the first voltage signal in the target alarm threshold to the minimum value of the voltage signal detected by the hydrogen sensor 21 during the previous hydrogen leak detection when there was no leak, rather than the voltage signal detected in the current instance, the target alarm threshold is reduced. This mitigates the possibility of a high target alarm threshold due to aging, further enabling earlier detection of leak trends and preventing potential danger.

[0068] Specifically, MCU3 determines whether the increased value exceeds the level 3 alarm threshold. If it does, it controls the hydrogen energy conversion power system of the hydrogen-powered driving device to cut off power and controls the audible and visual alarm device 4 to activate the audible and visual alarm. If it does not exceed the level 3 alarm threshold, it determines whether the increased value exceeds the level 2 alarm threshold. If it does, it controls the output power of the motor of the hydrogen energy conversion power system to be reduced to half of the rated power and controls the audible and visual alarm device 4 to activate the audible and visual alarm. If it does not exceed the level 2 alarm threshold, it determines whether the increased value exceeds the level 1 alarm threshold. If it does, it controls the display of the hydrogen-powered driving device to issue a warning and controls the alarm light of the audible and visual alarm device 4 to flash.

[0069] Since only a persistent leakage signal can cause the alarm counter to accumulate to the level that triggers an alarm, effectively filtering out transient environmental interference or random noise, this embodiment of the invention proposes a progressive multi-layer alarm strategy: Level 3 alarm, the method is power outage: the highest level of safety response, power outage of hydrogen-powered driving equipment, audible and visual warning to stay away from the vehicle.

[0070] Specifically, it determines whether the increased value exceeds the level 3 alarm threshold. If it does, it controls the hydrogen energy conversion power system of the hydrogen-powered driving device to shut down and activates the audible and visual alarm device 4. For example, the level 3 alarm threshold can be 8600ms.

[0071] Level 2 alarm, the method is to limit power: the power of the hydrogen-powered driving equipment is halved, entering limp state, and an audible and visual alarm is triggered.

[0072] Specifically, if the value is not greater than the level 3 alarm threshold, it is determined whether the increased value is greater than the level 2 alarm threshold. If it is greater than the level 2 alarm threshold, the output power of the motor in the hydrogen energy conversion power system is reduced to half of its rated power, and the audible and visual alarm device 4 is activated. For example, the level 2 alarm threshold can be 4600ms.

[0073] Level 1 alarm, indicated by a warning: prompt stop for inspection and repair, with flashing alarm lights.

[0074] Specifically, if the value is not greater than the secondary alarm threshold, it is determined whether the increased value exceeds the primary alarm threshold. If it does, the display of the hydrogen-powered driving device is controlled to issue a warning, and the alarm light of the audible and visual alarm device 4 is controlled to flash. For example, the primary alarm threshold can be 600ms.

[0075] Therefore, the above-mentioned three-tiered, progressive, multi-layered alarm strategy, from warning to traffic restriction and finally to protective power cut-off, provides riders with progressively escalating response times and clear coping guidelines, taking into account both safety and user experience.

[0076] In one implementation, MCU3 is further used to determine if the compensated voltage signal does not exceed the target alarm threshold. If so, it reduces the alarm counter value by a preset value, indicating that it may only be a single interference. Then, it clears the alarm counter value and returns to the MCU, which adjusts the heating power of the heating element 23 based on the ambient temperature and a preset temperature control algorithm to control the heating temperature of the heating element 23. The minimum value of the alarm counter is 0.

[0077] In one implementation, the MCU3 is also used to send a reset signal after the maintenance personnel have inspected and repaired the hydrogen energy conversion power system of the hydrogen-powered driving device and the sound and light alarm device 4 has been powered off and activated. After receiving the reset signal, the MCU3 supplies power to the hydrogen energy conversion power system and returns to the execution MCU to adjust the heating power of the heating element 23 based on the ambient temperature and the preset temperature control algorithm to control the heating temperature of the heating element 23.

[0078] In one implementation, the MCU3 is also used to maintain the current state after controlling the output power of the motor of the hydrogen energy conversion power system to be reduced to half of the rated power, and controlling the audible and visual alarm device 4 to issue an audible and visual alarm, or after controlling the display of the hydrogen-powered driving device to issue a warning and controlling the alarm light of the audible and visual alarm device 4 to flash, and then return to execute the MCU3 to adjust the heating power of the heating element 23 based on the ambient temperature and the preset temperature control algorithm to control the heating temperature of the heating element 23.

[0079] As described above, the hydrogen leak alarm system for hydrogen-powered driving equipment provided in this embodiment of the invention includes a temperature sensor 1, a hydrogen sensor 2, an MCU 3 with a built-in digital-to-analog converter (ADC), and an audible and visual alarm device 4, all installed within the frame 10 of the hydrogen-powered driving equipment. The hydrogen sensor 2 includes a hydrogen-sensitive element 21, a low-power operational amplifier 22, and a heating element 23. The hydrogen-sensitive element 21 is signal-connected to the low-power operational amplifier 22. The temperature sensor 1, the low-power operational amplifier 22, the heating element 23, and the audible and visual alarm device 4 are all signal-connected to the MCU 3. The hydrogen sensor 2 is located near the gas valve of the hydrogen storage tank of the hydrogen-powered driving equipment. The temperature sensor 1 sends the detected ambient temperature within the frame 10 to the MCU 3. The MCU 3 adjusts the heating of the heating element 23 based on the ambient temperature and a preset temperature control algorithm. The power is used to control the heating temperature of the heating element 23; the hydrogen-sensitive element 21 sends the detected voltage signal to the low-power operational amplifier 22; the low-power operational amplifier 22 performs signal following processing on the voltage signal to obtain the processed voltage signal, and sends it to the MCU3; the MCU3 determines the compensation parameter based on the ambient temperature, determines the compensation value based on the compensation parameter and the processed voltage signal, determines the compensated voltage signal based on the compensation value and the processed voltage signal, and determines whether the compensated voltage signal exceeds the target alarm threshold. If it exceeds the target alarm threshold, the value of the alarm counter is increased by a preset value, and the sound and light alarm device is controlled to alarm based on the increased value. The target alarm threshold is calculated based on the sum of the first voltage signal with a first ratio and the second voltage signal with a second ratio. The sum of the first ratio and the second ratio is 1, and the first ratio is less than the second ratio. Therefore, by employing a hydrogen-sensitive element 21 based on electrochemical principles, which has an intrinsic reaction speed far exceeding that of traditional semiconductor sensors, early leakage warning can be achieved, improving response speed. Furthermore, the MCU3 adjusts the heating power of the heating element 23 based on ambient temperature and a preset temperature control algorithm to control the heating temperature of the heating element 23. This allows the MCU3 to dynamically adjust the heating power applied to the heating element 3 according to the ambient temperature feedback from the temperature sensor 1, rather than continuously heating at full power, significantly reducing power consumption. By using integral judgment on the alarm counter instead of single-point instantaneous judgment, only a continuously existing leakage signal can cause the alarm counter to accumulate to the level that triggers an alarm, effectively filtering out transient environmental interference or random noise, greatly improving anti-interference capability and reliability, and reducing the occurrence of false alarms or missed alarms.

[0080] Specifically, hydrogen-powered driving devices may include, but are not limited to, the following two types of devices: The first type: hydrogen-powered two-wheeled vehicles The hydrogen leak alarm system for hydrogen-powered driving equipment provided in this embodiment of the invention is installed at the interface between the hydrogen cylinder and the hydrogen energy conversion power system of a hydrogen-powered two-wheeled vehicle, thereby providing early warning of hydrogen leaks.

[0081] The second type: hydrogen-powered drones The hydrogen leak alarm system for hydrogen-powered vehicles provided in this embodiment of the invention is installed at the interface between the hydrogen cylinder and the hydrogen energy conversion power system of a hydrogen-powered drone, thereby monitoring and alarming for hydrogen leaks within a limited space.

[0082] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0083] Those skilled in the art will understand that the modules in the apparatus of the embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they can be further divided into multiple sub-modules.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hydrogen leak alarm system for hydrogen-powered vehicles, characterized in that, The device includes a temperature sensor, a hydrogen sensor, a microcontroller unit (MCU) with a built-in analog-to-digital converter (ADC), and an audible and visual alarm device, all installed within the frame of the hydrogen-powered driving equipment. The hydrogen sensor includes a hydrogen-sensitive element, a low-power operational amplifier, and a heating element. The hydrogen-sensitive element is connected to the low-power operational amplifier. The temperature sensor, the low-power operational amplifier, the heating element, and the audible and visual alarm device are all connected to the MCU. The hydrogen-sensitive element is located near the gas valve of the hydrogen storage tank of the hydrogen-powered driving device. The temperature sensor sends the detected ambient temperature inside the rack to the MCU; The MCU adjusts the heating power of the heating element based on the ambient temperature and a preset temperature control algorithm to control the heating temperature of the heating element; The hydrogen-sensitive element sends the detected voltage signal to the low-power operational amplifier; The low-power operational amplifier performs signal following processing on the voltage signal to obtain a processed voltage signal, and sends it to the MCU; The MCU determines compensation parameters based on the ambient temperature, determines compensation values ​​based on the compensation parameters and the processed voltage signal, determines a compensated voltage signal based on the compensation value and the processed voltage signal, and determines whether the compensated voltage signal exceeds the target alarm threshold. If it does, the value of the alarm counter is increased by a preset value, and the audible and visual alarm device is controlled to sound an alarm based on the increased value. The target alarm threshold is calculated based on the sum of a first voltage signal at a first ratio and a second voltage signal at a second ratio. The sum of the first ratio and the second ratio is 1, and the first ratio is less than the second ratio.

2. The system as described in claim 1, characterized in that, The hydrogen sensor also includes a circuit board (PCB), a multi-core cable, and a waterproof connector. The hydrogen-sensitive element, the low-power operational amplifier, and the heating element are all mounted on the PCB board, which is fixed in the mounting holes of the frame. The low-power operational amplifier is signal-connected to one end of the multi-core cable, and the other end of the multi-core cable is provided with the waterproof connector. The waterproof connector is pluggably connected to the MCU. The mounting hole is close to the gas valve of the hydrogen storage tank of the hydrogen-powered driving device.

3. The system as described in claim 1, characterized in that, The MCU is also used to determine whether the ambient temperature exceeds a preset temperature threshold. If so, it reduces the heating power of the heating element to the power corresponding to the ambient temperature.

4. The system as described in claim 1, characterized in that, The MCU is also connected to the controller of the hydrogen-powered driving device. The MCU is also used to determine whether it has received a start signal from the controller. If so, it adjusts the heating power of the heating element to the rated frequency.

5. The system as described in claim 1, characterized in that, The MCU determines whether the increased value exceeds the third-level alarm threshold. If it does, it controls the hydrogen energy conversion power system of the hydrogen-powered driving device to cut off power and controls the audible and visual alarm device to activate an audible and visual alarm. If the increased value does not exceed the third-level alarm threshold, it determines whether the increased value exceeds the second-level alarm threshold. If it does, it controls the output power of the motor of the hydrogen energy conversion power system to be reduced to half of its rated power and controls the audible and visual alarm device to activate an audible and visual alarm. If the increased value does not exceed the second-level alarm threshold, it determines whether the increased value exceeds the first-level alarm threshold. If it does, it controls the display of the hydrogen-powered driving device to issue a warning and controls the alarm light of the audible and visual alarm device to flash.

6. The system as described in claim 1, characterized in that, The MCU determines the compensation parameters based on the correspondence between the ambient temperature and the pre-stored temperature and compensation parameters, calculates the difference between the processed voltage signal and the compensation parameters as the compensation value, and calculates the sum of the compensation value and the processed voltage signal as the compensated voltage signal.

7. The system as described in claim 1, characterized in that, The first voltage signal is the minimum value of the voltage signal detected by the hydrogen-sensitive element when there was no hydrogen leak during the last hydrogen leak detection. The second voltage signal is the voltage signal detected by the hydrogen-sensitive element when the air contains 4% hydrogen.

8. The system as described in claim 1, characterized in that, The MCU is also used to determine that the processed voltage signal does not exceed the target alarm threshold, reduce the value of the alarm counter by the preset value, and return to execute the MCU to adjust the heating power of the heating element based on the ambient temperature and the preset temperature control algorithm to control the heating temperature of the heating element.

9. The system as described in claim 1, characterized in that, The MCU is also used to, after controlling the hydrogen energy conversion power system of the hydrogen-powered driving device to shut down and controlling the audible and visual alarm device to activate the audible and visual alarm, to supply power to the hydrogen energy conversion power system after receiving a reset signal, and return to execute the MCU to adjust the heating power of the heating element based on the ambient temperature and the preset temperature control algorithm to control the heating temperature of the heating element.

10. The system as claimed in claim 1, characterized in that, The MCU is also used to control the heating element's heating power to control the heating temperature of the heating element after controlling the output power of the motor of the hydrogen energy conversion power system to be reduced to half of the rated power, and after controlling the audible and visual alarm device to issue an audible and visual alarm, or after controlling the display of the hydrogen-powered driving device to issue a warning and controlling the alarm light of the audible and visual alarm device to flash.

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