Hydrogen leakage detection device and detection method

Abstract

The invention provides a hydrogen leakage detection device and a detection method. The hydrogen leakage detection device comprises a release system which is configured to be installed near a target leakage source and used for being controlled to actively release hydrogen-containing standard gas to the environment where the target leakage source is located, and the hydrogen content in the hydrogen-containing standard gas is a fixed value; the sampling system is configured to be installed near the target leakage source and used for sucking environmental gas in the environment where the target leakage source is located; the detection system is connected with the sampling system and is used for detecting first hydrogen concentration data in the environmental gas sucked into the sampling system when the release system is closed and detecting second hydrogen concentration data in the environmental gas sucked into the sampling system when the release system is started; and determining whether a target leakage source has hydrogen leakage according to the second hydrogen concentration data and the first hydrogen concentration data.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen energy equipment safety detection, and particularly relates to a hydrogen leakage detection device and a detection method. BACKGROUND

[0002] In the links of hydrogen energy production, preparation, storage, transportation and utilization, etc., there are often situations of densely configuring liquid hydrogen, gaseous hydrogen and other gas / liquid medium process pipelines, containers and subassemblies in a limited space. In the existing leakage safety monitoring technology, one or more different types of sensors are usually combined, such as catalytic combustion type, electrochemical type, hydrogen-sensitive palladium alloy type, and thermal conduction type single hydrogen concentration sensor or array installed near the leakage site for detection.

[0003] The above-mentioned detection technology can easily obtain a conclusion that leakage occurs in a certain area, but it has obvious deficiencies in determining the specific leakage source. Since the actual completion functions, operating pressures, sealing states and other working conditions of liquid hydrogen, gaseous hydrogen and other gas medium pipelines, containers and subassemblies are different, the risk levels and the urgency of treatment after leakage are also different, so it is necessary to determine the specific leakage source in practice.

[0004] In some applications, it is required to jointly determine by coupling process system parameters, which is not conducive to the implementation of the independent operation principle of the hydrogen leakage safety monitoring system, and increases the complexity and failure rate of the system. The single type sensor detection has deficiencies, and sometimes false alarms or large lags are easily generated. For example, the ultrasonic leakage sensor has a high probability of false negatives for leakage under a lower pressure level of 1.0 MPa, because the acoustic signal intensity in the detection frequency spectrum is significantly reduced. The catalytic combustion type and electrochemical type sensors have relatively slow response speed, and since oxygen in the air is required for participation, for the scene of rapid reduction of oxygen content in the air caused by expansion and diffusion after liquid hydrogen leakage, false alarms are easily generated.

[0005] A sampling leakage detection method and device are disclosed in a patent document with application number CN202311842100.4, which processes different flow rate suction methods and bidirectional suction sampling switching devices, and performs early warning judgment through the maximum concentration detected within a preset time period. However, the above-mentioned scheme still has the following defects:

[0006] Firstly, the scheme cannot realize reliable leakage positioning function;

[0007] Secondly, the scheme lacks verification of whether the entire detection system itself is effective;

[0008] Thirdly, since hydrogen is easy to diffuse, if the connection between the other intake holes in the path and the sampling pipe is not tight, "escape" occurs, the concentration reaching the detection end is reduced, and false alarm occurs.

[0009] Fourthly, detection controllers and valve pipe assemblies are arranged at both ends of the sampling pipe and control detection in both directions, which is relatively complex and time-consuming.

[0010] In other words, the scheme is relatively suitable for leak detection and alarm under the condition that the total distance of the sampling pipe is short and the number of intake holes is small, and the applicable range is relatively narrow.

[0011] Therefore, the present application is proposed. SUMMARY

[0012] The technical problem to be solved by the present application is to at least overcome part of the deficiencies of the prior art, and to provide a hydrogen leak detection device, which introduces active leakage other than the target leakage source by setting a release system, generates a reference response and analyzes characteristic changes, solves the problems of concentration detection fixed threshold dependence under unreliable conditions and false alarm caused by the absolute value of the concentration obtained by sampling being too low due to escape.

[0013] To solve the above technical problems, the basic idea of the technical solution of the present application is to provide a hydrogen leak detection device in a first aspect, comprising:

[0014] A release system configured to be installed near the target leakage source for actively releasing hydrogen-containing standard gas into the environment where the target leakage source is located under control, the hydrogen content in the hydrogen-containing standard gas being a fixed value;

[0015] A sampling system configured to be installed near the target leakage source for inhaling environmental gas in the environment where the target leakage source is located; and

[0016] A detection system connected to the sampling system for detecting first hydrogen concentration data in the environmental gas inhaled by the sampling system when the release system is closed and detecting second hydrogen concentration data in the environmental gas inhaled by the sampling system when the release system is started, and determining whether the target leakage source leaks hydrogen according to the second hydrogen concentration data and the first hydrogen concentration data.

[0017] In some embodiments, the number of target leakage sources is multiple;

[0018] The release system comprises:

[0019] A standard gas source for containing hydrogen-containing standard gas;

[0020] A release pipeline connected to the standard gas source for controlled conduction or interruption, configured to be arranged on one side of the target leakage source and at the same height as the target leakage source;

[0021] a plurality of bleed holes, which are arranged on the pipe wall of the release pipeline in a spaced manner along the extension direction of the release pipeline and correspond to the plurality of target leakage sources one by one, for actively bleeding the hydrogen-containing standard gas.

[0022] In some embodiments, the sampling system comprises:

[0023] a sampling pipeline, which is connected to the detection system and is configured to be arranged above the target leakage source;

[0024] a plurality of sampling holes, which are arranged on the pipe wall of the sampling pipeline in a spaced manner along the extension direction of the sampling pipeline and correspond to the plurality of bleed holes one by one, for inhaling the ambient gas.

[0025] In some embodiments, the release pipeline is further provided with a starting mark bleed hole at one end close to the standard gas source, and the starting mark bleed hole is away from the target leakage source.

[0026] The sampling pipeline is further provided with a starting mark sampling hole at one end close to the detection system, and the position of the starting mark sampling hole corresponds to the position of the starting mark bleed hole.

[0027] In some embodiments, the detection system comprises:

[0028] a detection chamber, which is controlled to be connected or cut off with the sampling pipeline, for accommodating the inhaled ambient gas;

[0029] a gas concentration sensor, which is arranged in the detection chamber, for detecting the hydrogen concentration in the ambient gas to obtain the first hydrogen concentration data and the second hydrogen concentration data; and

[0030] a detection controller, which is arranged outside the detection chamber and is connected to the gas concentration sensor, for controlling the connection or cut off between the release pipeline and the standard gas source, the connection or cut off between the detection chamber and the sampling pipeline, and determining whether the target leakage source has hydrogen leakage according to the second hydrogen concentration data and the first hydrogen concentration data.

[0031] Preferably, the detection system further comprises an alarm, which is connected to the detection controller, for issuing an alarm prompt of hydrogen leakage.

[0032] The second aspect of the present application provides a hydrogen leakage detection method, which uses the hydrogen leakage detection device as described above, and comprises:

[0033] Without starting the release system, using the sampling system to inhale ambient gas in the environment where the target leakage source is located, and using the detection system to detect first hydrogen concentration data in the ambient gas;

[0034] When it is determined that the first hydrogen concentration data exceeds a first hydrogen concentration threshold and does not exceed a second hydrogen concentration threshold, controlling the release system to start a preset time interval, within the preset time interval, using the sampling system to inhale ambient gas in an environment where a target leakage source is located, and using the detection system to detect second hydrogen concentration data in the ambient gas;

[0035] Whether leakage occurs at the target leakage source is determined according to a relationship between the second hydrogen concentration data and pre-stored standard hydrogen concentration data.

[0036] In some embodiments, the standard hydrogen concentration data includes the number of standard peaks and the waveform of each standard peak;

[0037] The step of determining whether a target leakage source is leaking according to the relationship between the second hydrogen concentration data and pre-stored standard hydrogen concentration data includes:

[0038] Determine that the number of standard peaks in the second hydrogen concentration data is the same as the number of standard peaks in the standard hydrogen concentration data, and

[0039] If the waveforms of the respective standard peaks in the second hydrogen concentration data correspond one-to-one with the waveforms of the respective standard peaks in the standard hydrogen concentration data and satisfy similarity determination, it is determined that no leakage occurs at the target leakage source;

[0040] Or if the waveforms of the respective standard peaks in the second hydrogen concentration data and at least one of the waveforms of the respective standard peaks in the standard hydrogen concentration data do not satisfy the similarity determination, it is determined that the target leakage source corresponding to at least one waveform has leaked.

[0041] In some embodiments, the step of determining whether the waveforms of each standard peak in the second hydrogen concentration data and the waveforms of each standard peak in the standard hydrogen concentration data satisfy a one-to-one correspondence similarity determination includes:

[0042] determining whether a ratio between a peak value of each standard peak in the second hydrogen concentration data and a peak value of each standard peak in the standard hydrogen concentration data satisfies a first preset range;

[0043] Preferably, the step of determining that the waveform of each standard peak in the second hydrogen concentration data and at least one of the waveforms of each standard peak in the standard hydrogen concentration data do not satisfy similarity determination includes:

[0044] determining that the target leakage source is in a mild leakage state when the ratio between the peak value of the at least one waveform and the peak value of the corresponding standard peak in the standard hydrogen concentration data meets a second preset range;

[0045] Alternatively, determining that the target leakage source is in a moderate leakage state when the ratio between the peak value of the at least one waveform and the peak value of the corresponding standard peak in the standard hydrogen concentration data meets a third preset range.

[0046] In some embodiments, the standard hydrogen concentration data comprises a standard peak number and a waveform of each standard peak.

[0047] The step of determining whether the target leakage source leaks according to the relationship between the second hydrogen concentration data and the pre-stored standard hydrogen concentration data comprises:

[0048] determining that the number of standard peaks in the second hydrogen concentration data is less than the number of standard peaks in the standard hydrogen concentration data;

[0049] and the ratio between the highest peak value in the second hydrogen concentration data and the highest peak value in the standard hydrogen concentration data meets a fourth preset range, determining that the target leakage source corresponding to the highest peak value is in a severe leakage state.

[0050] In some embodiments, when the first hydrogen concentration data exceeds a second hydrogen concentration threshold value, it is determined that leakage occurs near the target leakage source.

[0051] Preferably, when the first hydrogen concentration data exceeds the second hydrogen concentration threshold value, the release system is controlled to start a preset time interval, and in the preset time interval, the sampling system is used to inhale ambient gas in the environment where the target leakage source is located, and the detection system is used to detect the second hydrogen concentration data in the ambient gas.

[0052] According to the relationship between the second hydrogen concentration data and the pre-stored standard hydrogen concentration data, the target leakage source is located.

[0053] After the above technical solutions are adopted, the present application has the following beneficial effects compared with the prior art.

[0054] The hydrogen leakage detection device and method provided by the present application introduce active leakage other than the target leakage source by setting the release system, generate a reference response and analyze the characteristic changes, solve the problem of fixed threshold value dependence of concentration detection under unreliable conditions and the problem of false alarm caused by the absolute value of the concentration obtained by sampling being too low due to escape.

[0055] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0056] The accompanying drawings, which are part of this application, serve to provide further understanding of the present application, and the schematic embodiments of the present application and the descriptions thereof serve to explain the present application, but do not constitute undue limitations on the present application. Obviously, the drawings in the following description are only some embodiments, and other drawings can be obtained from these drawings by those of ordinary skill in the art without creative labor. In the drawings:

[0057] Figure 1 is a partial structural schematic diagram of a hydrogen leakage detection device provided according to an exemplary embodiment of the present application;

[0058] Figure 2 is a flow schematic diagram of a hydrogen leakage detection method provided according to an exemplary embodiment of the present application.

[0059] In the drawings: 100, hydrogen leakage detection device;

[0060] 10, release system, 11, standard gas source; 12, release pipeline; 13, bleed hole; 14, release valve; 15, starting mark bleed hole;

[0061] 20, sampling system; 21, sampling pipeline; 22, sampling hole; 23, starting mark sampling hole; 24, sampling valve;

[0062] 30, detection system; 31, detection chamber; 32, gas concentration sensor; 33, detection controller; 34, flow meter.

[0063] It should be noted that these drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments will be described clearly and completely below in conjunction with the drawings of the embodiments of the present application. The following embodiments are used to illustrate the present application, but not to limit the scope of the present application.

[0065] In the description of the present application, it should be noted that the terms "up", "down", "front", "back", "left", "right", "vertical", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0066] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "linking" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0067] Figure 1 A partial structural schematic diagram of a hydrogen leakage detection device 100100 provided according to an exemplary embodiment of the present application is shown. The detection device preferably detects whether hydrogen leakage occurs in the potential leakage source in the environment where gas, liquid hydrogen and other components are densely arranged in a limited space.

[0068] As shown in Figure 1 The hydrogen leakage detection device 100 includes a release system 10, a sampling system 20 and a detection system 30. The release system 10 is configured to be installed near the target leakage source, for releasing hydrogen-containing standard gas into the environment where the target leakage source is located in a controlled manner, and the hydrogen content in the hydrogen-containing standard gas is a fixed value. The sampling system 20 is configured to be installed near the target leakage source, for inhaling the environmental gas in the environment where the target leakage source is located. The detection system 30 is connected with the sampling system 20, for detecting the first hydrogen concentration data in the environmental gas inhaled by the sampling system 20 when the release system 10 is closed, and detecting the second hydrogen concentration data in the environmental gas inhaled by the sampling system 20 when the release system 10 is started, and determining whether hydrogen leakage occurs in the target leakage source according to the second hydrogen concentration data and the first concentration data.

[0069] The number of the above-mentioned target leakage sources is multiple, for example, it is the places where leakage is easy to occur, such as pipe joints, welding points in the hydrogen pipeline system, storage system, filling system, and it can also occur on the surface of the pipe, the surface of the tank, the hydrogen / liquid hydrogen filling port, the hydrogen compressor, etc.

[0070] It should be noted that in order to improve the safety of the hydrogen equipment operation at the target leakage source, the present application limits the upper limit of the hydrogen content in the hydrogen-containing standard gas. For example, when the hydrogen-containing standard gas uses a hydrogen-nitrogen mixture, the upper limit of the hydrogen content is not more than 5% Vol. If the hydrogen-containing standard gas uses a hydrogen-air mixture, the upper limit of the hydrogen content is not higher than 4% Vol. However, in order to avoid the situation that the actively leaked hydrogen of the release system 10 cannot be detected, the lower limit of the hydrogen content in the hydrogen-containing standard gas should also be limited. For example, the lower limit of the hydrogen content in the hydrogen-containing standard gas can be limited according to the lower limit of the detectable concentration of the gas concentration sensor 32 in the detection system 30. For example, the lower limit of the hydrogen content in the hydrogen-containing standard gas is K1 times the lower limit of the detectable concentration of the gas concentration sensor 32 in the detection system 30, preferably K1≥3. It can be understood that the lower limit of the detectable concentration of the gas concentration sensor 32 refers to the minimum concentration of the hydrogen content in the ambient gas that can be stably identified by the gas concentration sensor 32.

[0071] In some embodiments, the release system 10 includes a standard gas source 11, a release pipeline 12, and a plurality of release orifices 13. The standard gas source 11 is, for example, a container such as a tank having a containing chamber capable of containing a hydrogen-containing standard gas, which can adopt a structure commonly used in the art and will not be described here. The release pipeline 12 is configured to be arranged on one side of the target leakage source and at the same height as the target leakage source. That is, the release pipeline 12 is arranged adjacent to the target leakage source to be detected at approximately the same height. The extension length of the release pipeline 12 can cover a plurality of target leakage sources, and a plurality of release orifices 13 are arranged on the pipe wall of the release pipeline 12 along the extension direction of the release pipeline 12, one-to-one corresponding to the plurality of target leakage sources, for actively releasing the hydrogen-containing standard gas.

[0072] The release pipeline 12 and the standard gas source 11 are controlled to be connected or cut off to achieve the purpose of actively releasing the hydrogen-containing standard gas into the environment where the target leakage source is located through the plurality of release orifices 13. For example, a release valve 14 is arranged between the release pipeline 12 and the standard gas source 11, which is used to connect or cut off the standard gas source 11 and the release pipeline 12. The release valve 14 can be, for example, a pneumatic valve, a solenoid valve, or other structures commonly used in the art.

[0073] The sampling system 20 includes a sampling line 21 and multiple sampling holes 22 disposed on the sampling line 21. The sampling line 21 extends approximately the same length as the release line 12 and is positioned above and near the target leak source. The multiple sampling holes 22 are spaced along the length of the sampling line 21 and correspond one-to-one with the multiple release holes 13. These holes are used to draw in ambient gas. The sampling line 21 is connected to the detection system 30 to transmit the drawn-in ambient gas to the detection system 30.

[0074] Specifically, in the hydrogen system to be tested, the N target leakage sources are respectively recorded as LK1, LK2, LK i , ...LK N The number of the sampling holes 22 on the sampling line 21 and the number of the discharge holes 13 on the release line 12 are also N, and their positions correspond one to one.

[0075] As an example, the N sampling holes 22 can be marked as SP1, SP2, SP3, SP4, SP5, SP6, SP7, SP8, SP9, SP10, SP11, SP12, SP13, SP14, SP15, SP16, SP17, SP18, SP19, SP20, SP21, SP22, SP19, SP23, SP24, SP1 i 、……SP N The N air release holes 13 on the release line 12 are marked as SF1, SF2, SF i 、……SF N . And SP i , SF i , LK i , 1≤i≤N, the spatial position distribution corresponds one to one. That is, each sampling hole 22SP of the sampling pipeline 21 i Located at the target leak source LK i Near the top of the pipe 12, to ensure that hydrogen leakage in this part can be diffused to the sampling line 21 as soon as possible under the action of negative pressure. i Located at sampling hole 22SP i Directly below, as close as possible to the target leak source LK i .

[0076] It should be noted that the installation positions of the sampling pipeline 21 and the release pipeline 12 are not changed after being determined, and thus the relative positions of the target leakage holes are also unchanged.

[0077] In some embodiments, a start mark release hole 15 is further provided on the end of the release line 12 close to the standard gas source 11, and the start mark release hole 15 is far away from the target leakage source; a start mark sampling hole 23 is further provided on the end of the sampling line 21 close to the detection system 30, and the position of the start mark sampling hole 23 corresponds to the position of the start mark release hole 15.

[0078] As an example, the start mark sampling hole 23 of the sampling pipeline 21 is marked as SP0, and the start mark release hole 15 on the release pipeline 12 is marked as SF0, wherein the start mark release hole 15 SF0 and the mark sampling hole marked as SP0 one-to-one correspond in spatial position distribution, and the side closest to the detection system 30, but there is no target leakage source near the position of the release pipeline 12 and the sampling pipeline 21. The start mark release hole 15 and the start mark sampling hole 23 serve as start marks of the standard gas source leakage detection waveform applied subsequently.

[0079] That is, because the start mark release hole 15 is arranged on the release pipeline 12, and the start mark sampling hole 23 is arranged on the sampling pipeline 21, the number of holes on the sampling pipeline 21 and the release pipeline 12 is N+1, which is one more than the number of target leakage sources.

[0080] Further, a sampling valve 24 is arranged between the sampling pipeline 21 and the detection system 30, and the sampling valve 24 is used to turn on or turn off the detection system 30 and the sampling pipeline 21. The sampling valve 24 can be, for example, a pneumatic valve, an electromagnetic valve, or other structures commonly used in the art.

[0081] Further, a flow meter 34 is arranged between the sampling pipeline 21 and the detection system 30, and is used to detect the flow of the ambient gas in the sampling pipeline 21. The flow meter 34 is installed on the sampling pipeline 21 close to the side of the detection system 30.

[0082] In some embodiments, the detection system 30 includes a detection chamber 31, a gas concentration sensor 32, and a detection controller 33. The detection chamber 31 has a holding chamber capable of holding the ambient gas inhaled by the sampling pipeline 21, and the detection chamber 31 and the sampling pipeline 21 are controlled to be turned on or cut off by the sampling valve 24. The gas concentration sensor 32 is arranged in the detection chamber 31, and is used to detect the hydrogen concentration in the ambient gas in the detection chamber 31 to obtain the first hydrogen concentration data and the second hydrogen concentration data. The detection controller 33 is arranged outside the detection chamber 31, and is connected with the gas concentration sensor 32, and is used to control the turning on or cutting off between the release pipeline 12 and the standard gas source 11, the turning on or cutting off between the detection chamber 31 and the sampling pipeline 21, and determine whether the target leakage source has hydrogen leakage according to the second hydrogen concentration data and the first hydrogen concentration data.

[0083] The detection controller 33 is, for example, a server or other device with certain computing power that can process the second hydrogen concentration data and the first hydrogen concentration data to determine whether hydrogen leakage occurs.

[0084] Preferably, the detection system 30 further comprises an alarm connected with the detection controller 33 for sending an alarm prompt of hydrogen leakage. The alarm is, for example, an audible and light alarm or the like commonly used in the art.

[0085] It should be noted that the detection chamber 31 is further provided with a vent for discharging the sampled ambient gas in the detection chamber 31 through the sampling pipeline 21.

[0086] In the above scheme, the gas concentration sensor 32 is arranged in the detection chamber 31, and the detection controller 33 is located outside the detection chamber 31, and the two are connected by a lead, so that the volume of the detection chamber 31 is as small as possible.

[0087] In addition, for a sensor with a low lower detection limit and a slow response and recovery time, such as an electrochemical sensor (the lower detection limit is 5 ppm, the response time is 35 s, and the recovery time is 60 s), a standard gas source 11 with a relatively low hydrogen content can be used to ensure that the standard peak is easy to determine and to shorten the recovery time. For a sensor with a high lower detection limit and a fast response time, such as a thermal conductivity detector (the lower detection limit is 500 ppm, the response time is 2 s, and the recovery time is 5 s), a standard gas source 11 with a relatively high hydrogen content can be used to facilitate the detection of hydrogen.

[0088] The operation mode of the hydrogen leakage detection device 100 will be described below.

[0089] After the hydrogen leakage detection device 100 is arranged, the device is self-tested in a non-leakage state to determine appropriate initial parameters and standard hydrogen concentration data.

[0090] Specifically, the detection controller 33 sends a start command to the release valve 14, the release valve 14 connects the release pipeline 12 to the standard gas source 11, and the plurality of release orifices 13 actively release hydrogen-containing standard gas into the environment where the target leakage source is located, and the release time is TA. It should be noted that TA is selected according to the distance from the release pipeline 12 to the sampling pipeline 21 and the test concentration of the hydrogen-containing standard gas released by the release pipeline 12, and optionally, the value of TA is in the range of 0.1 s < TA < 1 s. In addition, the value of the test concentration of the hydrogen-containing standard gas should be determined considering safety and detection sensitivity. When the test concentration is too low, the concentration of the diffused and sampled gas in the detection chamber 31 is too low to be detected.

[0091] When the release time reaches TA, the detection controller 33 sends a cut-off command to the release valve 14, the release valve 14 cuts off the release pipeline 12 from the standard gas source 11, and starts timing.

[0092] When the cut-off time reaches TB, the detection controller 33 issues a start command to the sampling valve 24 to open the sampling pipeline 21 to the detection chamber 31, and the ambient gas sucked in through the sampling orifice 22 flows into the detection chamber 31 at a first initial flow rate V1 under negative pressure sampling according to the gas flow rate fed back by the flow meter 34. Optionally, 0.1s<TB<1s, 3m / s<V1<10m / s. If the flow rate is too slow, the response time is too long, and the gas concentration decays along the sampling path of the sampling orifice, resulting in too little hydrogen entering the detection chamber 31, which cannot be detected. If the flow rate is too fast, it may impact the gas concentration sensor 32 in the detector, affecting the detection effect.

[0093] The first initial flow rate V1 is suitable and is determined by self-detection, that is, the detection controller 33 can obtain detection signals of N+1 standard peaks within a certain time period (e.g., 30s-180s), the number of standard peaks is equal to the total number of openings on the release pipeline 12 and the sampling pipeline 21 (N release orifices 13+1 initial standard release orifice 15, N sampling orifices 22+1 initial standard sampling orifice 23), and the peak values of the standard peaks gradually decrease from near to far relative to the detection chamber 31 along the extension direction of the sampling pipeline 21, because the hydrogen-containing standard gas diffused into the sampling pipeline 21 through the sampling orifice 22 and then into the detection chamber 31 gradually decays in concentration during the flow process, indicating that the device is normal.

[0094] At the same time, the detection controller 33 obtains the peak values of each standard peak S0, S1, …, SN+1 under the first initial flow rate. i ……S N The standard hydrogen concentration data is calibrated.

[0095] Specifically, the sampling start time, when the detection controller 33 issues a start command to the sampling valve 24 (to open the sampling pipeline 21 to the detection chamber 31 to sample at a first initial flow rate V1), is marked as T0, and then the absolute time Tj of reaching the peak value of each standard peak is recorded. j， 0≤j≤n, and the time interval ΔTi between adjacent two standard peaks. The zero time period is K0 times the lower limit of the gas concentration sensor 32 that can be detected in the detection system 30 near the zero output by the detection controller, 0 i If the zero time period is too short, the discrimination effect is poor, which affects the effective implementation of the calibration step. The peak values of the standard peaks corresponding to the leakage points from the nearest to the farthest end of the detection system 30 are marked as H0, H1, …, Hn+1. i ……Hn .

[0096] When the number of standard peaks detected by the detection controller 33 is less than N+1, the sealing of the sampling system 20 should be checked, and after confirming normality, the test should be performed again. If the phenomenon still exists, the first initial flow rate V1 should be appropriately increased or the release time TA should be prolonged or the cutoff time TB should be shortened before the test is performed again until the detection controller 33 obtains the detection signal of N+1 standard peaks.

[0097] In other words, in this process, the initial parameters to be determined include the first initial flow rate V1, the release time TA, and the cutoff time TB, and the standard hydrogen concentration data include the number of standard peaks and the waveform of each standard peak (the absolute time T j and the time interval AT between adjacent two standard peaks i and the peak value of each standard peak).

[0098] In addition, in this process, which is also the process of verifying whether the release system 10, the sampling system 20, and the detection system 30 are working normally, is equivalent to a system self-check, which is also very necessary. Because in the previous sampling and detection method, since most of the hydrogen equipment is in a non-leakage state, and the hydrogen leakage detection device 100 itself is abnormal or faulty, it can also cause the result of “normal” leakage detection (such as accidental disconnection of the sampling pipeline 21, failure of the gas concentration sensor 32 in the detection chamber 31, etc.), and the terminal display state is mistakenly considered to be “safe”. However, once leakage occurs, the hydrogen leakage detection device 100 still does not respond, which is very dangerous.

[0099] It should be noted that the above system self-check can be opened at a fixed time during the operation of the hydrogen leakage detection device 100, or can be manually opened.

[0100] After the initial parameters and the standard hydrogen concentration data are determined, the hydrogen leakage detection device 100 is restored to the initial state, and the medium in the sampling pipeline 21 is restored to a blank background gas atmosphere, so that it can be used to detect whether the target leakage source has hydrogen leakage.

[0101] Specifically, the release system 10 is closed, the sampling system 20 is started, and after all the signals obtained by the detection controller 33 are restored to zero, this time is marked as the blank background state, that is, the detection preparation before leakage is completed.

[0102] Figure 2 A flowchart of a detection method for detecting whether a target leakage source has hydrogen leakage by using the hydrogen leakage detection device 100 according to the above is shown.

[0103] As shown in Figure 2 , the execution of the detection method includes the following steps:

[0104] S110, under the condition that the release system is not started, the sampling system is used to suck the environment gas in the environment where the target leakage source is located, and the detection system is used to detect the first hydrogen concentration data in the environment gas;

[0105] S120, when the first hydrogen concentration data exceeds the first hydrogen concentration threshold value and does not exceed the second hydrogen concentration threshold value, the release system is controlled to start a preset time interval, in which the sampling system is used to suck the environment gas in the environment where the target leakage source is located, and the detection system is used to detect the second hydrogen concentration data in the environment gas;

[0106] S130, according to the relationship between the second hydrogen concentration data and the standard hydrogen concentration data stored in advance, it is determined whether the target leakage source leaks.

[0107] In detail, when the hydrogen leakage detection device 100 performs continuous routine detection in the process of normal operation of the hydrogen equipment, the release system 10 is kept closed, the sampling system 20 is started, and the first hydrogen concentration data detected by the detection system 30 is used for judgment.

[0108] When the detected first hydrogen concentration data exceeds the second hydrogen concentration threshold value, it is determined that serious leakage occurs near the target leakage source, and the alarm can be directly controlled to issue an alarm. The second hydrogen concentration threshold value is, for example, K3 times the lower limit of the gas concentration sensor 32, and optionally, K3≥3. Further, the release system 10 can be controlled to start a preset time interval, which is, for example, the aforementioned release time TA. In the release time TA, the sampling system 20 is used to suck the environment gas in the environment where the target leakage source is located, and the detection system 30 is used to detect the second hydrogen concentration data in the environment gas. According to the relationship between the second hydrogen concentration data and the standard hydrogen concentration data stored in advance, the target leakage source is located to realize reliable positioning of the leakage source.

[0109] It should be noted that the method of reliable positioning of the leakage source here is the same as the method of reliable positioning of the leakage source in the subsequent steps, which will be described in detail in the subsequent steps, and the present application will not be described here.

[0110] When the detected first hydrogen concentration data exceeds the first hydrogen concentration threshold value and does not exceed the second hydrogen concentration threshold value, the release system 10 is controlled to start a preset time interval, which is, for example, the aforementioned release time TA. In the release time TA, the sampling system 20 is used to suck the environment gas in the environment where the target leakage source is located, and the detection system 30 is used to detect the second hydrogen concentration data in the environment gas to further determine whether the target leakage source leaks. The first hydrogen concentration threshold value is, for example, K2 times the lower limit of the gas concentration sensor 32, and optionally, K2≥1.5.

[0111] It is to be noted that, according to the foregoing, the first hydrogen concentration data detected by the detection system 30 includes detection signals of N+1 standard peaks, and based on this, the first hydrogen concentration data exceeding the second hydrogen concentration threshold refers to the peak value of at least one of the N+1 standard peaks exceeding the second hydrogen concentration threshold, and the first hydrogen concentration data exceeding the first hydrogen concentration threshold and not exceeding the second hydrogen concentration threshold refers to the peak value of at least one of the N+1 standard peaks exceeding the first hydrogen concentration threshold and not exceeding the second hydrogen concentration threshold.

[0112] In some embodiments, when the detection controller 33 determines that the number of standard peaks in the second hydrogen concentration data is the same as the number of standard peaks in the standard hydrogen concentration data, and the waveform of each standard peak in the second hydrogen concentration data satisfies the similarity determination one by one with the waveform of each standard peak in the standard hydrogen concentration data, it is determined that the target leakage source does not leak.

[0113] When the detection controller 33 determines that the number of standard peaks in the second hydrogen concentration data is the same as the number of standard peaks in the standard hydrogen concentration data, and the waveform of each standard peak in the second hydrogen concentration data does not satisfy the similarity determination with at least one of the waveforms of each standard peak in the standard hydrogen concentration data, it is determined that the target leakage source corresponding to the at least one waveform leaks.

[0114] As an example, whether the waveform of each standard peak in the second hydrogen concentration data satisfies the similarity determination one by one with the waveform of each standard peak in the standard hydrogen concentration data includes determining whether the ratio between the peak value of each standard peak in the second hydrogen concentration data and the peak value of each standard peak in the standard hydrogen concentration data satisfies a first preset range K5, and optionally, 0.4≤K5≤1.5.

[0115] Specifically, the detection controller 33 collects N+1 standard peaks, and the waveforms of the N+1 standard peaks satisfy the similarity determination with the waveforms in the standard hydrogen concentration data, and the basis is that the peak value TH0, TH1, … THN+1 of each standard peak gradually decreases, and the absolute value of the peak value of each standard peak collected by the detection system 30 from the nearest to the farthest end of the leakage point and the peak value H0, H1, … HN+1 of each standard peak in the standard hydrogen concentration data from the nearest to the farthest end of the leakage point satisfy the ratio K5, then it is determined that the target leakage source does not leak, and the foregoing case that the detected first hydrogen concentration data exceeds the first hydrogen concentration threshold and does not exceed the second hydrogen concentration threshold is a special case caused by a short-term hydrogen concentration, and no alarm needs to be issued. j ……TH N ……TH j ……TH N ……TH

[0116] If the absolute value of the peak value of the distance detection system 30 from the nearest to the farthest leakage point in each standard peak collected is consistent with the peak value H0, H1, ... TH of the distance detection system 30 from the nearest to the farthest leakage point in each standard peak in the standard hydrogen concentration data j ...H N If at least one ratio between them is not K5, it is determined that a leak occurs near the target leakage source corresponding to at least one ratio, and the situation in which the first hydrogen concentration data detected exceeds the first hydrogen concentration threshold and does not exceed the second hydrogen concentration threshold is indeed caused by a leak in the target leakage source.

[0117] Specifically, at least one peak value among the peak values ​​of the collected standard peaks from the nearest to the farthest leakage point of the detection system 30 is not lower than the peak value of the previous waveform adjacent to it. That is, in the entire collected standard peak sequence, the peak value TH of the jth peak is j Not less than the peak value TH of the j-1th peak j-1 , 1≤j≤n, that is, the peak values ​​appearing in sequence over time show a non-gradual decrease phenomenon, which is considered to be a leak, and the location of the leak is located as the leak point LK j nearby.

[0118] Furthermore, when the detection controller 33 determines the peak value TH of the at least one waveform j The peak value H of the corresponding standard peak in the standard hydrogen concentration data j The ratio between them is recorded as K6, and when K6 meets the second preset range, it is determined that the target leakage source has a slight leakage. Optionally, the second preset range is 2-4.

[0119] Alternatively, when the detection controller 33 determines the peak value TH of the at least one waveform j The peak value H of the corresponding standard peak in the standard hydrogen concentration data j The ratio between them is recorded as K6, and when K6 meets the third preset range, it is determined that the target leakage source has a moderate leakage. Optionally, the third preset range is 4-5.

[0120] In addition, the step of determining whether a target leakage source is leaking according to the relationship between the second hydrogen concentration data and pre-stored standard hydrogen concentration data further includes:

[0121] determining that the number of standard peaks in the second hydrogen concentration data is less than the number of standard peaks in the standard hydrogen concentration data;

[0122] If the ratio of the highest peak value in the second hydrogen concentration data to the highest peak value in the standard hydrogen concentration data satisfies a fourth preset range, it is determined that a severe leak occurs in the target leakage source corresponding to the highest peak value.

[0123] Specifically, if M standard peaks are collected, M≤N, the highest peak value is TH j , 1≤j≤n, the ratio between the highest peak value and the highest peak value H j in the standard hydrogen concentration data is recorded as K6, 5≤K6, then a leakage alarm is given and the leakage is located at LK j , a serious leakage alarm is given.

[0124] When the hydrogen concentration entering the detector through the sampling system is high, i.e. a serious leakage occurs, the detector generates a high peak value response. When a particularly serious leakage occurs, the detection controller can even be overloaded and saturated due to exceeding the upper limit of detection. In the subsequent time, even if the concentration of the incoming gas sampled continuously decreases rapidly, even to normal air in a non-leakage state, the detector can only gradually recover to zero. In summary, due to the high leakage concentration at this location, the detection controller 33 cannot recover to a lower level before the next peak arrives, so that the adjacent one, even multiple locations in the direction away from the detection controller 33 miss the release of the peak waveform response corresponding to the standard gas containing hydrogen. The number of standard peaks and the highest peak value characteristics are changed.

[0125] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed as above with the preferred embodiments, it is not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the above-mentioned technical content without departing from the scope of the technical solution of the present application, and any simple modification, equivalent change and modification of the above-mentioned embodiments according to the technical essence of the present application are still within the scope of the present application.

Claims

1. A hydrogen leak detection device, characterized in that: include: A release system is configured to be installed near a target leakage source and is used to actively release a hydrogen-containing standard gas into an environment where the target leakage source is located in a controlled manner, wherein the hydrogen content of the hydrogen-containing standard gas is a fixed value; a sampling system configured to be installed near a target leak source and to aspirate ambient gas from an environment where the target leak source is located; and a detection system connected to the sampling system, configured to detect first hydrogen concentration data in the ambient gas inhaled into the sampling system when the release system is turned off, and to detect second hydrogen concentration data in the ambient gas inhaled into the sampling system when the release system is turned on, and to determine whether a hydrogen leak occurs at a target leakage source based on the second hydrogen concentration data and the first hydrogen concentration data.

2. The hydrogen leak detection device according to claim 1, characterized in that There are multiple target leakage sources; Wherein, the release system comprises: A standard gas source, used for containing hydrogen-containing standard gas; a release pipeline, which is controlled to be connected or cut off from the standard gas source, and is configured to be arranged on one side of the target leakage source and at the same height as the target leakage source; A plurality of gas discharge holes are arranged on the pipe wall of the release pipeline at intervals along the extension direction of the release pipeline and correspond one-to-one to a plurality of target leakage sources, and are used for actively discharging hydrogen-containing standard gas.

3. The hydrogen leak detection device according to claim 2, characterized in that: The sampling system comprises: a sampling line connected to the detection system and configured to be positioned above and near a target leak source; and A plurality of sampling holes are arranged on the pipe wall of the sampling pipeline at intervals along the extension direction of the sampling pipeline and correspond one-to-one with the plurality of discharge holes for inhaling ambient gas.

4. The hydrogen leak detection device according to claim 3, characterized in that: A start mark release hole is further provided at one end of the release pipeline close to the standard gas source, and the start mark release hole is away from the target leakage source; A start mark sampling hole is further provided on one end of the sampling pipeline close to the detection system, and the position of the start mark sampling hole corresponds to the position of the start mark discharge hole.

5. The hydrogen leak detection device according to claim 3 or 4, characterized in that: The detection system comprises: a detection chamber, which is controllably connected to or disconnected from the sampling line and is used to contain the inhaled ambient gas; a gas concentration sensor, disposed in the detection chamber, for detecting the hydrogen concentration in the ambient gas to obtain the first hydrogen concentration data and the second hydrogen concentration data; and a detection controller, disposed outside the detection chamber and connected to the gas concentration sensor, for controlling the connection or disconnection between the release line and the standard gas source, the connection or disconnection between the detection chamber and the sampling line, and determining whether hydrogen leakage occurs at the target leakage source based on the second hydrogen concentration data and the first hydrogen concentration data; Preferably, the detection system further comprises an alarm, which is connected to the detection controller and is used to issue an alarm prompt of hydrogen leakage.

6. A hydrogen leak detection method, characterized in that: The hydrogen leakage detection device according to any one of claims 1 to 5 comprises: Without starting the release system, using the sampling system to inhale ambient gas in the environment where the target leakage source is located, and using the detection system to detect first hydrogen concentration data in the ambient gas; When it is determined that the first hydrogen concentration data exceeds a first hydrogen concentration threshold and does not exceed a second hydrogen concentration threshold, controlling the release system to start a preset time interval, within the preset time interval, using the sampling system to inhale ambient gas in an environment where a target leakage source is located, and using the detection system to detect second hydrogen concentration data in the ambient gas; Whether leakage occurs at the target leakage source is determined according to a relationship between the second hydrogen concentration data and pre-stored standard hydrogen concentration data.

7. The hydrogen leak detection method according to claim 6, characterized in that: The standard hydrogen concentration data includes the number of standard peaks and the waveform of each standard peak; The step of determining whether a target leakage source is leaking according to the relationship between the second hydrogen concentration data and pre-stored standard hydrogen concentration data includes: Determine that the number of standard peaks in the second hydrogen concentration data is the same as the number of standard peaks in the standard hydrogen concentration data, and If the waveforms of the respective standard peaks in the second hydrogen concentration data correspond to the waveforms of the respective standard peaks in the standard hydrogen concentration data and satisfy similarity determination, it is determined that no leakage occurs at the target leakage source; Or if the waveforms of the respective standard peaks in the second hydrogen concentration data and at least one of the waveforms of the respective standard peaks in the standard hydrogen concentration data do not satisfy the similarity determination, it is determined that the target leakage source corresponding to at least one waveform has leaked.

8. The hydrogen leak detection method according to claim 7, characterized in that: The step of determining whether the waveforms of the respective standard peaks in the second hydrogen concentration data and the waveforms of the respective standard peaks in the standard hydrogen concentration data satisfy similarity determination in a one-to-one correspondence includes: determining whether a ratio between a peak value of each standard peak in the second hydrogen concentration data and a peak value of each standard peak in the standard hydrogen concentration data satisfies a first preset range; Preferably, the step of determining that the waveform of each standard peak in the second hydrogen concentration data and at least one of the waveforms of each standard peak in the standard hydrogen concentration data do not satisfy similarity determination includes: determining that a ratio between a peak value of the at least one waveform and a peak value of a corresponding standard peak in the standard hydrogen concentration data satisfies a second preset range, and determining that a slight leakage occurs at the target leakage source; Alternatively, if it is determined that the ratio between the peak value of the at least one waveform and the peak value of the corresponding standard peak in the standard hydrogen concentration data satisfies a third preset range, it is determined that a moderate leakage occurs in the target leakage source.

9. The hydrogen leak detection method according to claim 6, characterized in that: The standard hydrogen concentration data includes the number of standard peaks and the waveform of each standard peak; The step of determining whether a target leakage source is leaking according to the relationship between the second hydrogen concentration data and pre-stored standard hydrogen concentration data includes: determining that the number of standard peaks in the second hydrogen concentration data is less than the number of standard peaks in the standard hydrogen concentration data; If the ratio of the highest peak value in the second hydrogen concentration data to the highest peak value in the standard hydrogen concentration data satisfies a fourth preset range, it is determined that a severe leak occurs in the target leakage source corresponding to the highest peak value.

10. The hydrogen leakage detection method according to any one of claims 6 to 9, characterized in that: When it is determined that the first hydrogen concentration data exceeds a second hydrogen concentration threshold, it is determined that a leak occurs near the target leak source; Preferably, when it is determined that the first hydrogen concentration data exceeds a second hydrogen concentration threshold, the release system is controlled to start a preset time interval, and within the preset time interval, the sampling system is used to inhale the ambient gas in the environment where the target leakage source is located, and the detection system is used to detect the second hydrogen concentration data in the ambient gas; The target leakage source is located according to the relationship between the second hydrogen concentration data and pre-stored standard hydrogen concentration data.

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