An adaptive methane gas detection system and method based on infrared technology

Abstract

The invention discloses an adaptive methane gas detection system and method based on infrared technology, relates to the field of adaptive detection technology, and solves the technical problems of ignoring the detection error caused by long-term operation of a device and environmental changes in methane detection, and being difficult to adaptively adjust the detection cycle according to the detection result; the invention obtains a device correction factor by detecting and analyzing a comparison channel, and obtains an environmental correction factor by analyzing environmental information; detects the detection channel to obtain the detection intensity of infrared light, adjusts the detection intensity based on the device correction factor and the environmental correction factor to obtain the final intensity, obtains the methane concentration in the detection channel based on the final intensity, and performs an alarm operation based on the methane concentration; analyzes the methane concentration to obtain the detection time interval for the next detection in the current detection area; the invention improves the accuracy and reliability of the methane detection system through a comprehensive correction and adaptive adjustment mechanism.

Description

Technical Field

[0001] The invention belongs to the field of gas detection, and relates to an adaptive detection technology, in particular to an adaptive methane gas detection system and method based on infrared technology. Background Art

[0002] Methane is a flammable and explosive gas, and its leakage may lead to explosion accidents, seriously threatening the safety of personnel and equipment facilities. Traditional methane detection methods such as catalytic combustion sensors and electrochemical sensors have problems such as slow response speed, poor selectivity, and susceptibility to interference from other gases. Compared with other types of sensors, methane detectors based on infrared absorption principles have the advantages of high sensitivity, fast response, and non-contact measurement. In particular, with the development of optoelectronics, miniaturized and integrated infrared light sources and detectors have made portable and even wearable high-precision methane detection possible.

[0003] At present, most adaptive methane gas detection systems based on infrared technology ignore the detection errors caused by long-term operation of the device and environmental changes in methane detection. When such errors exist and are not eliminated, the detection results will be disturbed by the errors, resulting in inaccurate detection results, which may seriously lead to safety accidents. At the same time, it is difficult to adaptively adjust the detection cycle according to the detection results in methane detection, and the detection cycle of different environments cannot be dynamically adjusted. In situations where the methane concentration changes rapidly, the fixed detection cycle may not be able to detect the rapid changes in concentration in time, which may delay the best time for emergency treatment.

[0004] Therefore, the present invention discloses an adaptive methane gas detection system and method based on infrared technology, which are used to solve the above technical problems. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art; to this end, the present invention proposes an adaptive methane gas detection system and method based on infrared technology, which are used to solve the technical problems of ignoring the detection errors caused by long-term operation of the device and environmental changes in methane detection, and difficulty in adaptively adjusting the detection cycle according to the detection results. The present invention obtains the contrast intensity of infrared light by detecting the comparison channel and obtains the device correction factor by analysis, and obtains the environment correction factor by analyzing the environmental information; obtains the detection intensity of infrared light by detecting the detection channel, adjusts the detection intensity based on the device correction factor and the environment correction factor to obtain the final intensity, obtains the methane concentration in the detection channel based on the final intensity, and performs an alarm operation based on the methane concentration; and solves the above problems by analyzing the methane concentration to obtain the detection time interval for the next detection in the current detection area.

[0006] To achieve the above object, the first aspect of the present invention provides an adaptive methane gas detection system based on infrared technology, comprising: an adaptive adjustment unit, and a data acquisition unit, an adaptive control unit and a database connected thereto;

[0007] The data acquisition unit is used to obtain environmental information of the detection area; wherein the environmental information includes regional temperature, regional humidity, and gas pressure;

[0008] The adaptive adjustment unit is used to detect the comparison channel to obtain the comparison intensity of infrared light, analyze the comparison intensity to obtain the device correction factor; analyze the environmental information to obtain the environmental correction factor; detect the detection channel to obtain the detection intensity of infrared light, adjust the detection intensity based on the device correction factor and the environmental correction factor to obtain the final intensity, obtain the methane concentration in the detection channel based on the final intensity, and perform an alarm operation based on the methane concentration; wherein the comparison channel is a manually set channel, including comparison channel 1 and comparison channel 2;

[0009] The adaptive control unit is used to analyze the methane concentration to obtain the detection time interval for the next detection in the current detection area.

[0010] Preferably, the obtaining of environmental information of the detection area includes:

[0011] Acquire several temperatures of the detection area through the temperature sensor, acquire several humidity of the detection area through the humidity sensor, and acquire several gas pressures of the detection area through the gas pressure sensor;

[0012] The regional temperature QW is obtained based on the formula QW=(α1×ZGW+α2×ZDW+PJW) / 2; wherein α1 and α2 are proportional adjustment coefficients, and α1+α2=1, α1>α2; ZGW is the highest temperature of this test, ZDW is the lowest temperature of this test, and PJW is the average temperature of this test;

[0013] The regional humidity QS is obtained based on the formula QS=(α3×ZGS+α4×ZDS+PJS) / 2; where α3 and α4 are proportional adjustment coefficients, and α3+α4=1, α3>α4; ZGS is the highest humidity detected, ZDS is the lowest humidity detected, and PJS is the average humidity detected;

[0014] The gas pressure QP is obtained based on the formula QP=(α5×ZGP+α6×ZDP+PJP) / 2; wherein α5 and α6 are proportional adjustment coefficients, and α5+α6=1, α5>α6; ZGP is the highest gas pressure detected this time, ZDP is the lowest gas pressure detected this time, and PJP is the average gas pressure detected this time.

[0015] Preferably, the detecting of the contrast channel to obtain the contrast intensity of the infrared light comprises:

[0016] The channel filled with methane gas of standard concentration 1 is marked as comparison channel 1, and the channel filled with methane gas of standard concentration 2 is marked as comparison channel 2; wherein the standard concentration 1 and the standard concentration 2 are obtained by manual setting;

[0017] Turn on the infrared light source, use an infrared detector at the receiving point to receive the intensity of the infrared light passing through comparison channel one, QD1, and use an infrared detector at the receiving point to receive the intensity of the infrared light passing through comparison channel two, QD2;

[0018] The intensity 1 QD1 and the intensity 2 QD2 are collectively referred to as the control intensity of this analysis.

[0019] Preferably, the analysis based on the control intensity to obtain the device correction factor comprises:

[0020] A1: Extract intensity QD1, obtain ratio BL1 based on the formula BL1=(QD1-BQD1) / BQD1, and determine whether the value of ratio BL1 is within the first preset range; if yes, jump to A2; if no, issue a device failure alarm; wherein BQD1 is the manually set standard intensity 1, BQD2 is the manually set standard intensity 2, and the first preset range and the second preset range are obtained through experience;

[0021] A2: Extract the intensity QD2, obtain the ratio BL2 based on the formula BL2=(QD2-BQD2) / BQD2, and determine whether the value of the ratio BL2 is within the second preset range; if yes, jump to A3; if no, issue a device failure alarm;

[0022] A3: The device correction factor ZYZ is obtained based on the formula ZYZ=δ1×exp(-β1×|BL1|)+δ2×exp(-β2×|BL2|); wherein δ1 and δ2 are both proportional adjustment coefficients greater than 0, and δ1+δ2=1, δ1>δ2; β1 and β2 are both amplitude adjustment coefficients greater than 0.

[0023] It is worth noting that since the methane gas detection device needs to be in the detection state for a long time, when the methane gas detection device runs for a long time, it may cause malfunctions in core devices such as infrared light source emitters and infrared detectors. At this time, if the faulty device is used to detect the methane concentration, it will bring certain safety hazards. Therefore, by setting up two comparison channels to analyze the comparison intensity, it is determined whether the current device has a fault. If the fault cannot be corrected, an alarm message is issued. If the fault can be corrected, the device correction factor is calculated to provide data support for the correction of subsequent analysis results.

[0024] Preferably, the step of analyzing the environmental information to obtain the environmental correction factor includes:

[0025] B1: Extract the regional temperature QW and determine whether the regional temperature QW is out of the operating temperature range set by the device; if yes, issue a temperature over-limit warning signal; if no, jump to B2;

[0026] B2: Extract the regional humidity QS and determine whether the regional humidity QS is not within the operating humidity range set by the device; if yes, issue a humidity over-limit warning signal; if no, jump to B3;

[0027] B3: Extract the gas pressure QP and determine whether the gas pressure QP is not within the working gas pressure range set by the device; if yes, issue a gas pressure exceeding standard warning signal; if no, jump to B4;

[0028] B4: The environmental correction factor HYZ is obtained based on the formula HYZ=exp(μ1×(QW-BQW) / BQW+μ2×(QS-BQS) / BQS+μ3×(QP-BQP) / BQP); wherein μ1, μ2 and μ3 are all proportional adjustment coefficients greater than 0, and μ1+μ2+μ3=1; BQW is the manually set standard area temperature, BQS is the manually set standard area humidity, and BQP is the manually set standard gas pressure.

[0029] It is worth noting that the present invention takes temperature, humidity and gas pressure into comprehensive consideration to obtain a correction factor that can adjust the infrared intensity at the receiving end. This correction factor can make the system suitable for complex and changeable detection environments, ensuring the accuracy of the detection results while improving the practicality of the detection device.

[0030] It is worth noting that the increase in temperature, humidity and gas pressure will cause the intensity of infrared rays received by the infrared detector to decrease, further causing the methane concentration obtained by analysis to be lower than the actual concentration in the detection environment. The environmental correction factor obtained by the present invention, which takes temperature, humidity and gas pressure into comprehensive consideration, can compensate for the technical problem of inaccurate infrared intensity received due to the environment, avoid false alarms caused by inaccurate analysis results, and reduce safety hazards.

[0031] Preferably, the detecting channel to obtain the detection intensity of the infrared light includes:

[0032] An infrared detector is used at a receiving point to receive the intensity of the infrared light passing through the detection channel, and the intensity of the infrared light is marked as the detection intensity.

[0033] Preferably, the adjusting the detection intensity based on the device correction factor and the environment correction factor to obtain the final intensity includes:

[0034] The device correction factor ZYZ, the environmental correction factor HYZ and the detection intensity CQD are extracted, and the final intensity ZQD is obtained based on the formula ZQD=(γ1×ZYZ+γ2×HYZ)×CQD; wherein γ1 and γ2 are proportional adjustment coefficients, and γ1+γ2=1.

[0035] Preferably, obtaining the methane concentration in the detection channel based on the final intensity comprises:

[0036] Extracting several final intensity ZQDs and methane concentrations from a database, integrating the final intensity ZQDs and methane concentrations into several groups of training data and test data; using the training data to train an artificial intelligence model; using the test data to test the trained artificial intelligence model, and adjusting the artificial intelligence model according to the test results; finally obtaining a concentration matching model with the final intensity ZQD as input and the methane concentration as output; wherein the artificial intelligence model includes a BP neural network model or an RBF neural network model;

[0037] The final intensity ZQD of this analysis is input into the concentration matching model to obtain the methane concentration detected this time.

[0038] Specifically, the final intensity ZQD in the test data is input into the trained artificial intelligence model to obtain the corresponding methane concentration, and the methane concentration is compared with the corresponding methane concentration in the test data. When the difference between the two is within the threshold, which is obtained based on experience, there is no need to adjust the parameters and perform the next set of test data detection. If it is not within the threshold, the corresponding parameters are adjusted until the output methane concentration of the corresponding test data and the corresponding methane concentration in the test data are within the threshold, and then the next set of test data is detected. When the number of test data whose methane concentrations obtained from all test data and the corresponding methane concentrations in the test data are within the threshold, the concentration matching model with the final intensity ZQD as input and the methane concentration as output is obtained.

[0039] Preferably, the alarm operation based on methane concentration includes:

[0040] Extract the methane concentration detected this time and determine whether the methane concentration exceeds the concentration alarm threshold; if yes, issue a methane concentration exceeding the standard; if no, continue with the next methane concentration detection.

[0041] Preferably, the analysis of the methane concentration to obtain the detection time interval for the next detection in the current detection area includes:

[0042] The methane concentrations obtained from the most recent i detections are marked as JDn in order of time, and the change ratios BBLn between two adjacent detections are obtained based on the formula BBLn=(JDn-JDn-1) / JDn-1, and the average value BPJ of several change ratios BBLn is obtained, and it is determined whether the average value BPJ is greater than 0; if yes, the detection time interval BCJ between this detection and the previous detection is extracted, and the detection time interval CJ ​​between the next detection and this detection is obtained based on the formula CJ=σ1 / exp(BPJ)×BCJ; if no, the detection time interval BCJ between this detection and the previous detection is extracted, and the detection time interval CJ ​​between the next detection and this detection is obtained based on the formula CJ=(σ2×ln(|BPJ|+1)+1)×BCJ; wherein n represents a sequence number, and its value is [0,i]; σ1 and σ2 are both amplitude adjustment coefficients greater than 0.

[0043] It is noteworthy that the present invention adopts an intelligent detection strategy to automatically adjust the detection time interval by detecting changes in methane gas concentration, which helps to reduce the false alarm rate and improve the practicality and safety of the detection system.

[0044] A second aspect of the present invention provides an adaptive methane gas detection method based on infrared technology, comprising the following steps:

[0045] S1: Obtain environmental information of the detection area;

[0046] S2: Detect the comparison channel to obtain the comparison intensity of infrared light, and analyze the comparison intensity to obtain the device correction factor; analyze the environmental information to obtain the environmental correction factor; detect the detection channel to obtain the detection intensity of infrared light, adjust the detection intensity based on the device correction factor and the environmental correction factor to obtain the final intensity, obtain the methane concentration in the detection channel based on the final intensity, and perform an alarm operation based on the methane concentration;

[0047] S3: Analyze the methane concentration to obtain the detection time interval for the next detection in the current detection area.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] 1. The present invention obtains the contrast intensity of infrared light by detecting the comparison channel and obtains the device correction factor by analyzing the comparison channel, and obtains the environment correction factor by analyzing the environmental information; detects the detection channel to obtain the detection intensity of infrared light, adjusts the detection intensity based on the device correction factor and the environment correction factor to obtain the final intensity, obtains the methane concentration in the detection channel based on the final intensity, and performs an alarm operation based on the methane concentration; analyzes the methane concentration to obtain the detection time interval for the next detection in the current detection area, thereby solving the technical problems of ignoring the detection errors caused by long-term operation of the device and environmental changes, and being difficult to adaptively adjust the detection cycle according to the detection results in methane detection. The present invention improves the accuracy and reliability of the methane detection system through comprehensive correction and adaptive adjustment mechanisms.

[0050] 2. Since the methane gas detection device needs to be in the detection state for a long time, when the methane gas detection device runs for a long time, it may cause malfunctions in core devices such as infrared light source transmitters and infrared detectors. At this time, if the faulty device is used to detect the methane concentration, it will bring certain safety hazards. Therefore, the present invention sets up two comparison channels to analyze the comparison intensity to determine whether the current device has a fault. If the fault cannot be corrected, an alarm message is issued. If the fault can be corrected, the device correction factor is calculated to provide data support for the correction of subsequent analysis results.

[0051] 3. The present invention takes temperature, humidity and gas pressure into comprehensive consideration to obtain a correction factor that can adjust the infrared intensity at the receiving end. This correction factor can make the system suitable for complex and changeable detection environments, ensuring the accuracy of the detection results while improving the practicality of the detection device. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0053] Figure 1 It is a schematic diagram of the operation steps of the present invention;

[0054] Figure 2 is a schematic diagram of a system unit of the present invention;

[0055] Figure 3 A schematic diagram of the operation steps for obtaining the device correction factor of the present invention;

[0056] Figure 4 It is a schematic structural diagram of the detection device of the present invention.

[0057] In the figure: 1. Gas chamber; 2. Reference filter; 3. Pyroelectric detector; 4. Measuring filter; 5. Dual optical path; 6. Amplifier circuit; 7. Infrared light source. DETAILED DESCRIPTION

[0058] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0059] See also Figure 1-Figure 2 , the first aspect of the present invention provides an adaptive methane gas detection system based on infrared technology, including: an adaptive adjustment unit, and a data acquisition unit, an adaptive control unit, a database and a detection device connected thereto;

[0060] Data acquisition unit: used to obtain environmental information of the detection area; wherein the environmental information includes regional temperature, regional humidity, and gas pressure;

[0061] Adaptive adjustment unit: used to detect the contrast channel to obtain the contrast intensity of infrared light, analyze the contrast intensity to obtain the device correction factor; analyze the environmental information to obtain the environmental correction factor; detect the detection channel to obtain the detection intensity of infrared light, adjust the detection intensity based on the device correction factor and the environmental correction factor to obtain the final intensity, obtain the methane concentration in the detection channel based on the final intensity, and perform an alarm operation based on the methane concentration; wherein the contrast channel includes contrast channel 1 and contrast channel 2;

[0062] Adaptive control unit: used to analyze the methane concentration to obtain the detection time interval for the next detection in the current detection area;

[0063] See also Figure 4 As shown, the detection device includes an air chamber 1, an infrared light source 7 and an amplifier circuit 6 for amplifying the received signal;

[0064] The infrared light source 7 emits infrared light, part of which passes through the air chamber 1, the measuring filter 4 arranged between the amplifying circuit 6 and the air chamber 1, the dual optical path 5 and the pyroelectric detector 3, and the signal obtained by the pyroelectric detector 3 is amplified by the amplifying circuit 6 to obtain the detection intensity of the infrared light, and the channel where the route of this part of the infrared light is located is the detection channel; part of the light passes through the air chamber 1, the reference filter 2 arranged between the amplifying circuit 6 and the air chamber 1, the dual optical path 5 and the pyroelectric detector 3, and the signal obtained by the pyroelectric detector 3 is amplified by the amplifying circuit 6 to obtain the comparison intensity of the infrared light, and the channels where the route of this part of the infrared light is located are the comparison channel 1 and the comparison channel 2; the reference filter 2 and the measuring filter 4 mentioned above are one filter, and the difference is that the positions of the filters are different, and the difference between the comparison channel 1 and the comparison channel 2 is that the positions in the air chamber 1 are different.

[0065] It should be noted that the detection channel is used to measure the detection intensity of infrared light and the methane concentration in the air of the detection area.

[0066] For example, in this embodiment, the regional temperature QW=30°C, the regional humidity QS=50%, the gas pressure QP=100kpa; the standard concentration 1 is 60%, and the standard concentration 2 is 2%;

[0067] Turn on the infrared light source, use an infrared detector at the receiving point to receive the infrared light intensity QD1=0.7408W / m² passing through the comparison channel 1 filled with 60% methane gas content, and use an infrared detector at the receiving point to receive the infrared light intensity QD2=0.9900W / m² passing through the comparison channel 2 filled with 2% methane gas content;

[0068] Based on the formula BL1=(QD1-BQD1) / BQD1=(0.7408-0.75) / 0.75=-0.01226666666667, the ratio 1 BL1=-0.0122666666667 is obtained, and based on the formula BL2=(QD2-BQD2) / BQD2=(0.9900-1) / 1=-0.01, the ratio 2 BL2=-0.01 is obtained; wherein, in this embodiment, the standard intensity 1 BQD1 is taken as 0.75W / m², and the standard intensity 2 BQD2 is taken as 1W / m²;

[0069] Because the ratio 1 BL1 is within the first preset range, and the ratio 2 BL2 is within the first preset range, based on the formula ZYZ=δ1×exp(-β1×|BL1|)+δ2×exp(-β2×|BL2|)=0.6×exp(-0.96×|-0.0122666666667|)+0.4×exp(-0.96×|-0.01|)=0.99, the device correction factor ZYZ=0.99 is obtained; wherein, in this embodiment, the proportional adjustment coefficient δ1 is taken as 0.6, and the proportional adjustment coefficient δ2 is taken as 0.4; the amplitude adjustment coefficient β1 is taken as 0.96, and the amplitude adjustment coefficient β2 is taken as 0.96;

[0070] Since the values ​​of regional temperature QW, regional humidity QS, and gas pressure QP are all within the working range of the device setting, based on the formula HYZ=exp(μ1×(QW-BQW) / BQW+μ2×(QS-BQS) / BQS+μ3×(QP-BQP) / BQP)=exp(0.5×(30-28) / 28+0.4×(50-52) / 52+0.1×(100-96) / 96)=1.02, the environmental correction factor HYZ=1.02 is obtained;

[0071] Among them, in this embodiment, the value of the proportional adjustment coefficient μ1 is 0.5, the value of μ2 is 0.4, and the value of μ3 is 0.1; the standard area temperature BQW is 28°C, the standard area humidity BQS is 52%, and the standard gas pressure BQP is 96kpa;

[0072] An infrared detector is used at a receiving point to receive the intensity of infrared light passing through a detection channel, and the intensity of the infrared light is marked as a detection intensity;

[0073] The extraction device correction factor ZYZ=0.99, the environmental correction factor HYZ=1.02, the detection intensity CQD=0.9802W / m², based on the formula ZQD=(γ1×ZYZ+γ2×HYZ)×CQD=(0.5×0.99+0.5×1.02)×0.9802=0.97W / m², the final intensity ZQD=0.97W / m² is obtained;

[0074] The final intensity of this analysis, ZQD = 0.97W / m², was input into the concentration matching model to obtain the methane concentration of this detection as 6%;

[0075] Since the methane concentration detected this time is 6%, which does not exceed the concentration alarm threshold, the next methane concentration detection is continued; wherein, in this embodiment, the concentration alarm threshold is 10%;

[0076] The methane concentrations obtained from the most recent 10 detections are marked as JDn in order of time, and the change ratio BBLn between two adjacent detections is obtained based on the formula BBLn=(JDn-JDn-1) / JDn-1, and the average value BPJ of several change ratios BBLn is obtained. Since the average value BPJ is not greater than 0, the detection time interval BCJ between this detection and the previous detection is extracted, and the detection time interval CJ ​​between the next detection and this detection is obtained based on the formula CJ=(σ2×ln(|BPJ|+1)+1)×BCJ; wherein, in this embodiment, the value of i is 10.

[0077] In this application, the environmental information of the detection area is obtained, including:

[0078] Acquire several temperatures of the detection area through the temperature sensor, acquire several humidity of the detection area through the humidity sensor, and acquire several gas pressures of the detection area through the gas pressure sensor;

[0079] The regional temperature QW is obtained based on the formula QW=(α1×ZGW+α2×ZDW+PJW) / 2; wherein α1 and α2 are proportional adjustment coefficients, and α1+α2=1, α1>α2; ZGW is the highest temperature of this test, ZDW is the lowest temperature of this test, and PJW is the average temperature of this test;

[0080] The regional humidity QS is obtained based on the formula QS=(α3×ZGS+α4×ZDS+PJS) / 2; where α3 and α4 are proportional adjustment coefficients, and α3+α4=1, α3>α4; ZGS is the highest humidity detected, ZDS is the lowest humidity detected, and PJS is the average humidity detected;

[0081] The gas pressure QP is obtained based on the formula QP=(α5×ZGP+α6×ZDP+PJP) / 2; wherein α5 and α6 are proportional adjustment coefficients, and α5+α6=1, α5>α6; ZGP is the highest gas pressure detected this time, ZDP is the lowest gas pressure detected this time, and PJP is the average gas pressure detected this time.

[0082] It should be noted that the several temperatures can be temperature data obtained by several temperature sensors at the same time, or can be several temperature data obtained by one temperature sensor in a short time; the several humidity and several gas pressures can be obtained in the same way as the several temperatures.

[0083] In this application, the contrast channel is detected to obtain the contrast intensity of infrared light, including:

[0084] The channel filled with methane gas of standard concentration 1 is marked as comparison channel 1, and the channel filled with methane gas of standard concentration 2 is marked as comparison channel 2; wherein the standard concentration 1 and the standard concentration 2 are obtained by manual setting;

[0085] Turn on the infrared light source, use an infrared detector at the receiving point to receive the intensity of the infrared light passing through comparison channel one, QD1, and use an infrared detector at the receiving point to receive the intensity of the infrared light passing through comparison channel two, QD2;

[0086] The intensity 1 QD1 and the intensity 2 QD2 are collectively referred to as the control intensity of this analysis.

[0087] It should be noted that both comparison channel 1 and comparison channel 2 are sealed channels.

[0088] It should be noted that the value of standard concentration one in the present invention is greater than standard concentration two. The range of standard concentration one is generally 2 to 6 times the proportion of methane content in the atmosphere, and the range of standard concentration two is generally 0 to 1 times the proportion of methane content in the atmosphere.

[0089] See also Figure 3 In this application, the device correction factor is obtained based on the analysis of the control intensity, including:

[0090] A1: Extract intensity QD1, obtain ratio BL1 based on the formula BL1=(QD1-BQD1) / BQD1, and determine whether the value of ratio BL1 is within the first preset range; if yes, jump to A2; if no, issue a device failure alarm; wherein BQD1 is the manually set standard intensity 1, BQD2 is the manually set standard intensity 2, and the first preset range and the second preset range are obtained through experience;

[0091] A2: Extract the intensity QD2, obtain the ratio BL2 based on the formula BL2=(QD2-BQD2) / BQD2, and determine whether the value of the ratio BL2 is within the second preset range; if yes, jump to A3; if no, issue a device failure alarm;

[0092] A3: The device correction factor ZYZ is obtained based on the formula ZYZ=δ1×exp(-β1×|BL1|)+δ2×exp(-β2×|BL2|); wherein δ1 and δ2 are both proportional adjustment coefficients greater than 0, and δ1+δ2=1, δ1>δ2; β1 and β2 are both amplitude adjustment coefficients greater than 0.

[0093] In this application, environmental information is analyzed to obtain environmental correction factors, including:

[0094] B1: Extract the regional temperature QW and determine whether the regional temperature QW is out of the operating temperature range set by the device; if yes, issue a temperature over-limit warning signal; if no, jump to B2;

[0095] B2: Extract the regional humidity QS and determine whether the regional humidity QS is not within the operating humidity range set by the device; if yes, issue a humidity over-limit warning signal; if no, jump to B3;

[0096] B3: Extract the gas pressure QP and determine whether the gas pressure QP is not within the working gas pressure range set by the device; if yes, issue a gas pressure exceeding standard warning signal; if no, jump to B4;

[0097] B4: The environmental correction factor HYZ is obtained based on the formula HYZ=exp(μ1×(QW-BQW) / BQW+μ2×(QS-BQS) / BQS+μ3×(QP-BQP) / BQP); wherein μ1, μ2 and μ3 are all proportional adjustment coefficients greater than 0, and μ1+μ2+μ3=1; BQW is the manually set standard area temperature, BQS is the manually set standard area humidity, and BQP is the manually set standard gas pressure.

[0098] It should be noted that changes in temperature will affect the speed of thermal motion of gas molecules. When the temperature rises, the speed of gas molecules increases, resulting in more significant absorption and scattering of infrared rays, which will reduce the intensity of infrared rays received by the receiving device. Increased humidity will introduce more water vapor molecules, which have a strong absorption capacity for infrared rays. When the humidity is high, infrared rays will be absorbed by water during propagation, resulting in a decrease in the intensity of infrared rays reaching the receiving device. Changes in gas pressure will affect the density of gas molecules. When the gas pressure increases, the density of gas molecules increases, resulting in more opportunities for infrared rays to interact with gas molecules during propagation, thereby increasing the absorption and scattering of infrared rays, resulting in a decrease in the intensity of infrared rays reaching the receiving device. In the methane detection device, adding analysis of temperature, humidity and pressure can make the calculation results more accurate.

[0099] In this application, the detection channel is detected to obtain the detection intensity of infrared light, including:

[0100] An infrared detector is used at a receiving point to receive the intensity of the infrared light passing through the detection channel, and the intensity of the infrared light is marked as the detection intensity.

[0101] In this application, the detection intensity is adjusted based on the device correction factor and the environmental correction factor to obtain the final intensity, including:

[0102] The device correction factor ZYZ, the environmental correction factor HYZ and the detection intensity CQD are extracted, and the final intensity ZQD is obtained based on the formula ZQD=(γ1×ZYZ+γ2×HYZ)×CQD; wherein γ1 and γ2 are proportional adjustment coefficients, and γ1+γ2=1.

[0103] In this application, the methane concentration in the detection channel is obtained based on the final intensity, including:

[0104] Extracting several final intensity ZQDs and methane concentrations from a database, integrating the final intensity ZQDs and methane concentrations into several groups of training data and test data; using the training data to train an artificial intelligence model; using the test data to test the trained artificial intelligence model, and adjusting the artificial intelligence model according to the test results; finally obtaining a concentration matching model with the final intensity ZQD as input and the methane concentration as output; wherein the artificial intelligence model includes a BP neural network model or an RBF neural network model;

[0105] The final intensity ZQD of this analysis is input into the concentration matching model to obtain the methane concentration detected this time.

[0106] It should be noted that when training the concentration matching model, the methane concentration used is calculated using the formula. The specific calculation formula is:

[0107] ;

[0108] in, is the methane gas concentration to be measured; is the intensity of the transmitted light after passing through the channel, is the incident light intensity before passing through the channel; is the absorption line intensity of the gas to be measured that changes with temperature, is the gas pressure, It is the absorption path length of the laser passing through the methane gas to be measured.

[0109] In this application, alarm operations are performed based on methane concentration, including:

[0110] Extract the methane concentration of this detection and determine whether the methane concentration exceeds the concentration alarm threshold; if yes, issue a methane concentration exceeding the standard; if no, continue with the next methane concentration detection.

[0111] In this application, the methane concentration is analyzed to obtain the detection time interval for the next detection in the current detection area, including:

[0112] The methane concentrations obtained from the most recent i detections are marked as JDn in order of time, and the change ratio BBLn between two adjacent detections is obtained based on the formula BBLn=(JDn-JDn-1) / JDn-1, and the average value BPJ of several change ratios BBLn is obtained to determine whether the average value BPJ is greater than 0; if yes, the detection time interval BCJ between this detection and the previous detection is extracted, and the detection time interval CJ ​​between the next detection and this detection is obtained based on the formula CJ=σ1 / exp(BPJ)×BCJ; if no, the detection time interval BCJ between this detection and the previous detection is extracted, and the detection time interval CJ ​​between the next detection and this detection is obtained based on the formula CJ=(σ2×ln(|BPJ|+1)+1)×BCJ; wherein n represents the sequence number, and the value is [0,i]; σ1 and σ2 are both amplitude adjustment coefficients greater than 0.

[0113] It should be noted that when n=0, it indicates this detection.

[0114] It should be noted that when the average value BPJ is greater than 0, it means that most of the change ratios BBLn between two adjacent detections in the most recent n detections are greater than 0, further indicating that the methane concentration in the current area is increasing, so it is necessary to shorten the detection time interval between the next detection and the current detection; when the average value BPJ is not greater than 0, it means that most of the change ratios BBLn between two adjacent detections in the most recent n detections are not greater than 0, further indicating that the methane concentration in the current area is decreasing or remains unchanged, at this time, the detection time interval between the next detection and the current detection can be increased or maintained.

[0115] The second aspect of the present invention provides an adaptive methane gas detection method based on infrared technology, comprising the following steps:

[0116] S1: Obtain environmental information of the detection area;

[0117] S2: Detect the comparison channel to obtain the comparison intensity of infrared light, and analyze the comparison intensity to obtain the device correction factor; analyze the environmental information to obtain the environmental correction factor; detect the detection channel to obtain the detection intensity of infrared light, adjust the detection intensity based on the device correction factor and the environmental correction factor to obtain the final intensity, obtain the methane concentration in the detection channel based on the final intensity, and perform an alarm operation based on the methane concentration;

[0118] S3: Analyze the methane concentration to obtain the detection time interval for the next detection in the current detection area.

[0119] Part of the data in the above formula is calculated by removing the dimension and taking its numerical value. The formula is a formula closest to the actual situation obtained by software simulation of a large amount of collected data; the preset parameters and preset thresholds in the formula are set by technical personnel in this field according to actual conditions or obtained through simulation of a large amount of data.

[0120] Working principle of the present invention:

[0121] The present invention first obtains environmental information of the detection area; then detects the comparison channel to obtain the comparison intensity of infrared light, and analyzes the comparison intensity to obtain the device correction factor. This step enables the detection system to be suitable for situations where the device is prone to failure due to long-term work or harsh working environment, thereby improving the adaptability of the system; analyzes the environmental information to obtain the environmental correction factor. This step enables the system to be suitable for complex and changeable detection environments, thereby ensuring the accuracy of the detection results and improving the practicality of the detection device; finally, detects the detection channel to obtain the detection intensity of infrared light, adjusts the detection intensity based on the device correction factor and the environmental correction factor to obtain the final intensity, obtains the methane concentration in the detection channel based on the final intensity, and performs an alarm operation based on the methane concentration; analyzes the methane concentration to obtain the detection time interval for the next detection in the current detection area. This step adopts an intelligent detection strategy, and automatically adjusts the detection time interval by detecting changes in the methane gas concentration, thereby helping to reduce the false alarm rate and improving the practicality and safety of the detection system.

[0122] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. An adaptive methane gas detection system based on infrared technology, characterized in that: include: An adaptive adjustment unit, and a data acquisition unit, an adaptive control unit and a database connected thereto; The data acquisition unit is used to obtain environmental information of the detection area; wherein the environmental information includes regional temperature, regional humidity, and gas pressure; The adaptive adjustment unit is used to detect the comparison channel to obtain the comparison intensity of infrared light, analyze the comparison intensity to obtain the device correction factor; analyze the environmental information to obtain the environmental correction factor; detect the detection channel to obtain the detection intensity of infrared light, adjust the detection intensity based on the device correction factor and the environmental correction factor to obtain the final intensity, obtain the methane concentration in the detection channel based on the final intensity, and perform an alarm operation based on the methane concentration; wherein the comparison channel is a manually set channel, including comparison channel 1 and comparison channel 2; The adaptive control unit is used to analyze the methane concentration to obtain the detection time interval for the next detection in the current detection area; The step of adjusting the detection intensity based on the device correction factor and the environment correction factor to obtain the final intensity includes: Extract the device correction factor ZYZ, the environmental correction factor HYZ and the detection intensity CQD, and obtain the final intensity ZQD based on the formula ZQD=(γ1×ZYZ+γ2×HYZ)×CQD; where γ1 and γ2 are proportional adjustment coefficients, and γ1+γ2=1; The method of obtaining the methane concentration in the detection channel based on the final intensity includes: Extracting several final intensity ZQDs and methane concentrations from a database, integrating the final intensity ZQDs and methane concentrations into several groups of training data and test data; using the training data to train an artificial intelligence model; using the test data to test the trained artificial intelligence model, and adjusting the artificial intelligence model according to the test results; finally obtaining a concentration matching model with the final intensity ZQD as input and the methane concentration as output; wherein the artificial intelligence model includes a BP neural network model or an RBF neural network model; The final intensity ZQD of this analysis is input into the concentration matching model to obtain the methane concentration detected this time; The analysis of the methane concentration to obtain the detection time interval for the next detection in the current detection area includes: The methane concentrations obtained from the most recent i detections are marked as JDn in order of time, and the change ratios BBLn between two adjacent detections are obtained based on the formula BBLn=(JDn-JDn-1) / JDn-1, and the average value BPJ of several change ratios BBLn is obtained, and it is determined whether the average value BPJ is greater than 0; if yes, the detection time interval BCJ between this detection and the previous detection is extracted, and the detection time interval CJ ​​between the next detection and this detection is obtained based on the formula CJ=σ1 / exp(BPJ)×BCJ; if no, the detection time interval BCJ between this detection and the previous detection is extracted, and the detection time interval CJ ​​between the next detection and this detection is obtained based on the formula CJ=(σ2×ln(|BPJ|+1)+1)×BCJ; wherein n represents a sequence number, and its value is [0,i]; σ1 and σ2 are both amplitude adjustment coefficients greater than 0.

2. According to claim 1, the adaptive methane gas detection system based on infrared technology is characterized in that: The step of obtaining the environmental information of the detection area includes: Acquire several temperatures of the detection area through the temperature sensor, acquire several humidity of the detection area through the humidity sensor, and acquire several gas pressures of the detection area through the gas pressure sensor; The regional temperature QW is obtained based on the formula QW=(α1×ZGW+α2×ZDW+PJW) / 2; wherein α1 and α2 are proportional adjustment coefficients, and α1+α2=1, α1>α2; ZGW is the highest temperature of this test, ZDW is the lowest temperature of this test, and PJW is the average temperature of this test; The regional humidity QS is obtained based on the formula QS=(α3×ZGS+α4×ZDS+PJS) / 2; where α3 and α4 are proportional adjustment coefficients, and α3+α4=1, α3>α4; ZGS is the highest humidity detected, ZDS is the lowest humidity detected, and PJS is the average humidity detected; The gas pressure QP is obtained based on the formula QP=(α5×ZGP+α6×ZDP+PJP) / 2; wherein α5 and α6 are proportional adjustment coefficients, and α5+α6=1, α5>α6; ZGP is the highest gas pressure detected this time, ZDP is the lowest gas pressure detected this time, and PJP is the average gas pressure detected this time.

3. The adaptive methane gas detection system based on infrared technology according to claim 1 is characterized in that: The detecting of the contrast channel to obtain the contrast intensity of the infrared light comprises: The channel filled with methane gas of standard concentration 1 is marked as comparison channel 1, and the channel filled with methane gas of standard concentration 2 is marked as comparison channel 2; Turn on the infrared light source, use an infrared detector at the receiving point to receive the intensity of the infrared light passing through comparison channel one, QD1, and use an infrared detector at the receiving point to receive the intensity of the infrared light passing through comparison channel two, QD2; The intensity 1 QD1 and the intensity 2 QD2 are collectively referred to as the control intensity of this analysis.

4. The adaptive methane gas detection system based on infrared technology according to claim 3 is characterized in that: The device correction factor is obtained by analyzing based on the control intensity, including: A1: Extract intensity QD1, obtain ratio BL1 based on the formula BL1=(QD1-BQD1) / BQD1, and determine whether the value of ratio BL1 is within the first preset range; if yes, jump to A2; if no, issue a device failure alarm; wherein BQD1 is standard intensity 1, and BQD2 is standard intensity 2; A2: Extract the intensity QD2, obtain the ratio BL2 based on the formula BL2=(QD2-BQD2) / BQD2, and determine whether the value of the ratio BL2 is within the second preset range; if yes, jump to A3; if no, issue a device failure alarm; A3: The device correction factor ZYZ is obtained based on the formula ZYZ=δ1×exp(-β1×|BL1|)+δ2×exp(-β2×|BL2|); wherein δ1 and δ2 are both proportional adjustment coefficients greater than 0, and δ1+δ2=1, δ1>δ2; β1 and β2 are both amplitude adjustment coefficients greater than 0.

5. The adaptive methane gas detection system based on infrared technology according to claim 1 is characterized in that: The environmental correction factor obtained by analyzing the environmental information includes: B1: Extract the regional temperature QW and determine whether the regional temperature QW is out of the operating temperature range set by the device; if yes, issue a temperature over-limit warning signal; if no, jump to B2; B2: Extract the regional humidity QS and determine whether the regional humidity QS is not within the operating humidity range set by the device; if yes, issue a humidity over-limit warning signal; if no, jump to B3; B3: Extract the gas pressure QP and determine whether the gas pressure QP is not within the working gas pressure range set by the device; if yes, issue a gas pressure exceeding standard warning signal; if no, jump to B4; B4: The environmental correction factor HYZ is obtained based on the formula HYZ=exp(μ1×(QW-BQW) / BQW+μ2×(QS-BQS) / BQS+μ3×(QP-BQP) / BQP); where μ1, μ2 and μ3 are all proportional adjustment coefficients greater than 0, and μ1+μ2+μ3=1; BQW is the standard area temperature, BQS is the standard area humidity, and BQP is the standard gas pressure.

6. The adaptive methane gas detection system based on infrared technology according to claim 1 is characterized in that: The alarm operation based on methane concentration includes: Extract the methane concentration detected this time and determine whether the methane concentration exceeds the concentration alarm threshold; if yes, issue a methane concentration exceeding the standard; if no, continue with the next methane concentration detection.

7. An adaptive methane gas detection method based on infrared technology, based on the adaptive methane gas detection system based on infrared technology according to any one of claims 1 to 6, characterized in that: S1: Obtain environmental information of the detection area; S2: Detect the contrast channel to obtain the contrast intensity of the infrared light, and analyze the contrast intensity to obtain the device correction factor; Analyze environmental information to obtain environmental correction factors; The detection channel is detected to obtain the detection intensity of infrared light, the detection intensity is adjusted based on the device correction factor and the environment correction factor to obtain the final intensity, the methane concentration in the detection channel is obtained based on the final intensity, and an alarm operation is performed based on the methane concentration; S3: Analyze the methane concentration to obtain the detection time interval for the next detection in the current detection area.

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