Laser gas measurement device, method, storage medium, and controller

Abstract

The present invention discloses a laser gas measurement device, method, storage medium, and controller. The device includes a laser light source module, an open measurement gas chamber, a closed gas block, and a laser detection module. In a first direction, the axes of the laser light source module, the open measurement gas chamber, the closed gas block, and the laser detection module are in a straight line. The device also includes: a control module connected to the laser light source module and the laser detection module, used to control the laser light source module to output a laser of a target central wavelength, obtain the detection light intensity generated by the laser detection module after the laser passes through the open measurement gas chamber and the closed gas block, determine the concentration of the gas to be measured according to the detection light intensity, and calibrate the central wavelength of the laser output by the laser light source module. The device places a standard closed gas block in the measurement light path, so that self-calibration and concentration measurement do not need to be switched, and the operation process of self-calibration can be simplified while ensuring the stability of gas measurement, as well as the complexity of the structure of the laser gas measurement device.

Description

Technical Field

[0001] The present invention relates to the technical field of gas concentration measurement, and in particular to a laser gas measurement device, method, storage medium and controller. Background Art

[0002] TD-LAS (Tunable Diode- Laser Absorption Spectroscopy) laser gas measurement technology is based on the absorption spectrum characteristics of different gas molecules at specific wavelengths to achieve non-contact measurement of gas concentration in the environment. Compared with traditional electrochemical, catalytic and semiconductor measurement methods that generate voltage / current signals by reacting with gas, laser gas measurement has the advantages of long life, strong anti-interference and high accuracy.

[0003] TD-LAS laser gas measurement technology requires temperature control of the laser device to lock the central wavelength of the output light source. However, with long-term operation and environmental changes, factors such as the intrinsic wavelength drift of the laser and the measurement error offset of the temperature control and temperature measurement unit will cause the central wavelength of the light source to shift. If the central wavelength of the light source shifts within a certain range, it will cause measurement failure. For example, domestic natural gas laser detection generally uses a central wavelength of 1653.7nm. If the central wavelength shifts by more than 0.3nm, it is difficult to measure the concentration of natural gas. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present invention is to provide a laser gas measurement device, which does not require switching between self-calibration and concentration measurement, simplifies the operation process of self-calibration while ensuring the stability of gas measurement, and simplifies the complexity of the structure of the laser gas measurement device.

[0005] The second object of the present invention is to provide a laser gas measurement method.

[0006] A third object of the present invention is to provide a computer-readable storage medium.

[0007] A fourth object of the present invention is to provide a controller.

[0008] To achieve the above-mentioned purpose, a first aspect of an embodiment of the present invention proposes a laser gas measuring device, which includes a laser light source module, an open measuring gas chamber, a closed gas block and a laser detection module. In a first direction, the axes of the laser light source module, the open measuring gas chamber, the closed gas block and the laser detection module are in a straight line. The device also includes: a control module, which is connected to the laser light source module and the laser detection module, and is used to control the laser light source module to output a laser of a target central wavelength, obtain the detection light intensity generated by the laser detection module after the laser passes through the open measuring gas chamber and the closed gas block, determine the concentration of the gas to be measured according to the detection light intensity, and calibrate the central wavelength of the laser output by the laser light source module, wherein the target central wavelength is determined by the gas to be measured.

[0009] According to the laser gas measuring device of the embodiment of the present invention, a standard closed gas block is placed in the measuring light path, so that self-calibration and concentration measurement do not need to be switched. While ensuring the stability of gas measurement, the operation process of self-calibration can be simplified, and the complexity of the structure of the laser gas measuring device is also simplified.

[0010] In addition, the laser gas measuring device proposed in the above embodiment of the present invention may also have the following additional technical features:

[0011] According to one embodiment of the present invention, the control module includes a computing and processing component, a temperature control component and a light source driving component, the computing and processing component is respectively connected to the temperature control component and the light source driving component, the temperature control component and the light source driving component are respectively connected to the laser light source module, the computing and processing component is used to control the temperature control component so that the laser detection module is at a target temperature, so that the laser light source module outputs a laser with a target central wavelength, wherein the target temperature is the temperature of the laser light source module when the computing and processing component controls the temperature control component and the light source driving component so that the absorption peak generated by the electrical signal converted from the detection light intensity is at a target position.

[0012] According to one embodiment of the present invention, the laser detection module is used to convert the detected light intensity into an electrical signal; the control module includes: an acquisition component, which is respectively connected to the laser detection module and the calculation and processing component, and is used to collect the electrical signal and amplify the electrical signal; the calculation and processing component is used to convert the amplified electrical signal into a voltage signal, and control the temperature control component and the light source driving component to determine the temperature of the laser light source module when the absorption peak generated by the voltage signal is at the target position.

[0013] According to one embodiment of the present invention, the calculation and processing component is used to: based on the maximum temperature value, control the temperature control component to reduce the temperature of the laser light source module with a first preset temperature step, and control the light source driving component to perform continuous scanning from the minimum current to the maximum current, so as to obtain the laser wavelength range output by the laser light source module and the laser intensity range detected by the laser detection module during the scanning process; if the target absorption wavelength is not within the laser wavelength range, return to execute the step of controlling the temperature control component to reduce the temperature of the laser light source module with a first preset temperature step; if the target absorption wavelength is within the laser wavelength range, control the temperature control component to reduce the temperature of the laser light source module with a second preset temperature step, and control the light source driving component to perform continuous scanning from the minimum current to the maximum current until the absorption peak generated by the voltage signal is scanned to the center point of the laser wavelength range, record the temperature of the temperature control component at this time, and obtain the target temperature.

[0014] According to one embodiment of the present invention, the computing and processing component is used to: obtain a first optical path length and a calibrated light intensity of the laser passing through the open measuring gas chamber, wherein the calibrated light intensity is the light intensity generated by the laser detection module based on the laser passing through the closed gas block when the open measuring gas chamber is not diffused with the gas to be measured; and calculate the concentration of the gas to be measured according to the first optical path length, the calibrated light intensity and the detection light intensity by utilizing the relationship between concentration and the first optical path length, the calibrated light intensity and the detection light intensity.

[0015] According to one embodiment of the present invention, the relationship between the concentration and the first optical path length, the calibration light intensity and the detection light intensity is expressed as follows:

[0016]

[0017] in, represents the concentration, represents a constant, represents the first optical path length, represents the detected light intensity, represents the calibrated light intensity.

[0018] According to an embodiment of the present invention, the closed gas block is made of a light-transmitting material and is filled with a gas to be tested of a preset concentration.

[0019] To achieve the above-mentioned purpose, the second aspect of the present invention proposes a laser gas measurement method, which is used in the laser gas measurement device proposed in the first aspect of the present invention, and the method includes: controlling the laser light source module to output a laser of a target central wavelength; obtaining the detection light intensity generated by the laser detection module after the laser passes through an open measurement gas chamber and a closed gas block; determining the concentration of the gas to be measured based on the detection light intensity, and calibrating the central wavelength of the laser output by the laser light source module, wherein the target central wavelength is determined by the gas to be measured.

[0020] To achieve the above objectives, a third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the laser gas measurement method provided in the second aspect of the present invention is implemented.

[0021] To achieve the above-mentioned purpose, the fourth aspect of the present invention proposes a controller, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the laser gas measurement method proposed in the second aspect of the present invention is implemented.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic diagram of a laser gas measuring device according to an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of calibrating the central wavelength according to an embodiment of the present invention;

[0025] Figure 3 is a schematic diagram of the absorption peak position during the calibration process of a specific embodiment of the present invention;

[0026] Figure 4 is a schematic diagram of the absorption peak position during the calibration process of another specific embodiment of the present invention;

[0027] Figure 5 is a schematic diagram of the position of the absorption peak during the calibration process of another specific embodiment of the present invention;

[0028] Figure 6 is a flow chart of a laser gas measurement method according to an embodiment of the present invention;

[0029] Figure 7 4 is a structural block diagram of a controller according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0031] Laser gas measurement technology is widely used in instruments in laboratory environments due to its absorption characteristics for specific wavelengths, and has the advantages of high measurement accuracy, long life, and strong anti-interference performance. As a measuring instrument, it needs to be regularly inspected and calibrated.

[0032] With the advancement of laser technology, the cost of laser materials has further decreased, and the application of laser measurement devices in industrial and civilian fields has further expanded. As a high-precision gas concentration measurement method, the stability of the center wavelength of laser gas measurement is a key indicator. If the center wavelength deviates within a certain range, it will directly lead to measurement failure; therefore, laser measurement needs to be tested during use. The simplest and most direct way is to manually introduce standard gas for detection. For products used in large quantities, manual detection will be greatly limited by time and cost. The spectroscopic method and the mechanically driven standard gas chamber method separate the measurement and calibration processes and have the ability to automatically detect. However, the spectroscopic method requires the addition of a spectroscopic lens and a set of laser signal detection circuits, which increases costs and the spectroscope is easily polluted by the environment, resulting in poor spectroscopic effects. Although the mechanically driven standard gas chamber method uses the same laser signal detection circuit for measurement and calibration, it needs to add the mechanical drive hardware of the standard gas chamber. Measurement cannot be performed during calibration, and the long-term movement of the mechanical drive device leads to increased costs and increased failure rates. Either method increases the complexity of the laser gas measurement device and has an adverse effect on reliability and cost. In the scenario of household natural gas laser measurement, we have about 300 million residential users. For such large-scale civil and industrial applications, the above methods are too complicated.

[0033] To solve the above problems, embodiments of the present invention provide a laser gas measurement device, method, storage medium, and controller. The laser gas measurement device, method, storage medium, and controller of embodiments of the present invention are described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0034] Figure 1 FIG. 1 is a schematic diagram of a laser gas measuring device according to an embodiment of the present invention. Figure 1As shown, the laser gas measuring device may include a laser light source module 10, an open measuring gas chamber 20, a closed gas block 30 and a laser detection module 40. In a first direction, the axes of the laser light source module 10, the open measuring gas chamber 20, the closed gas block 30 and the laser detection module 40 are in a straight line. The laser gas measuring device also includes: a control module 50, which is connected to the laser light source module 10 and the laser detection module 40, and is used to control the laser light source module 10 to output a laser of a target central wavelength, obtain the detection light intensity generated by the laser detection module 40 after the laser is transmitted through the open measuring gas chamber and the closed gas block, determine the concentration of the gas to be measured according to the detection light intensity, and calibrate the central wavelength of the laser output by the laser light source module 10, wherein the target central wavelength is determined by the gas to be measured.

[0035] The laser gas measurement device of the embodiment of the present invention places a standard closed gas block 30 in the measurement optical path. Specifically, the open measurement gas chamber 20 and the closed gas block 30 are arranged between the laser light source module 10 and the laser detection module 40, the laser light source module 10 is connected to the open measurement gas chamber 20 on one side of the laser light source module 10 emitting laser light, the open measurement gas chamber 20 is connected to the closed gas block 30, and the closed gas block 30 is connected to the laser detection module 40 on one side of the laser light source module 40 receiving laser light, wherein in a first direction, the axes of the laser light source module 10, the open measurement gas chamber 20, the closed gas block 30 and the laser detection module 40 are in a straight line, so that the laser light emitted by the laser light source module 10 can sequentially pass through the open measurement gas chamber 20 and the closed gas block 30 and project to the laser detection module 40.

[0036] When the laser gas measuring device according to the embodiment of the present invention is used for self-calibration, the laser light source module 10, the closed gas block 30 and the laser detection module 40 can be used to implement self-calibration. When the laser gas measuring device according to the embodiment of the present invention is used for gas concentration measurement, the laser light source module 10, the open measurement gas chamber 20, the closed gas block 30 and the laser detection module 40 can be used to implement gas concentration measurement based on the gas to be measured diffused in the open measurement gas chamber 20 and the gas to be measured with known concentration in the closed gas block 30.

[0037] It should be noted that the laser gas measuring device of the embodiment of the present invention is aimed at detecting low-probability gas leakage conditions. Under normal circumstances, the standard closed gas block 30 can be used to self-detect and measure the central wavelength and measurement parameters. In the event of gas leakage, the concentration of the leaked gas is measured based on the light intensity superposition absorption of the standard closed gas block 30.

[0038] The laser gas measuring device of the embodiment of the present invention places a standard closed gas block 30 in the measuring light path, so that self-calibration and concentration measurement do not need to be switched. While ensuring the stability of gas measurement, the operation process of self-calibration can be simplified, and the complexity of the structure of the laser gas measuring device is also simplified.

[0039] Before using the laser gas measuring device to measure the concentration of the gas to be measured, the central wavelength of the laser output by the laser light source module 10 is calibrated to determine the temperature (target temperature) of the laser light source module 10 when the laser light source module 10 can output the laser of the target central wavelength. The control module 50 obtains the current temperature of the laser light source module 10 collected by the temperature sensor, and outputs a corresponding voltage signal to control the temperature control component 53 to heat or cool the laser light source module 10 to reach the target temperature according to the temperature difference between the current temperature and the target temperature. Among them, when controlling the temperature, the PID (Proportional Integral Derivative, proportional, integral and differential) control algorithm can be used to control the laser light source module 10 to reach the target temperature to lock the central wavelength of the laser output by the laser light source module 10. It should be noted that in the embodiment of the present invention, the laser light source module 10 includes a temperature sensor for collecting its temperature.

[0040] When the laser gas measuring device is used to measure the concentration of the gas to be measured, the laser gas measuring device is placed within the range of the gas to be measured, and the gas to be measured can enter the open measuring gas chamber 20 by free diffusion. The control module 50 controls the laser light source module 10 to output the laser of the target central wavelength by controlling the temperature control component 53. The laser emitted by the laser light source module 10 passes through the open measuring gas chamber 20 and then reaches the laser detection module 40 through the closed gas block 30. The laser detection module 40 detects the intensity of the projected laser light to obtain the detection light intensity, and the control module 50 determines the concentration of the gas to be measured according to the detection light intensity.

[0041] It should be noted that the open measurement chamber 20 and the closed gas block 30 in the embodiment of the present invention may be a cuboid, a cylinder, or other shapes. The embodiment of the present invention does not limit the shapes of the open measurement chamber 20 and the closed gas block 30. The length of the open measurement chamber 20 is L1, and the corresponding optical path length of the laser passing through the open measurement chamber 20 is also L1. The length of the closed gas block 30 is L0, and the corresponding optical path length of the laser passing through the closed gas block 30 is also L0.

[0042] In order to ensure the effectiveness of the measurement of the laser gas measurement device, the central wavelength of the laser output by the laser light source module 10 may be regularly detected and calibrated.

[0043] In one embodiment of the present invention, the control module 50 includes a computing and processing component 52, a temperature control component 53 and a light source driving component 54. The computing and processing component 52 is connected to the temperature control component 53 and the light source driving component 54, respectively. The temperature control component 53 and the light source driving component 54 are connected to the laser light source module 10, respectively. The computing and processing component 52 is used to control the temperature control component 53 so that the laser detection module 10 is at a target temperature, so that the laser light source module 10 outputs a laser with a target central wavelength, wherein the target temperature is the temperature of the laser light source module when the computing and processing component 52 controls the temperature control component 53 and the light source driving component 54 so that the absorption peak generated by the electrical signal converted from the detection light intensity is at the target position.

[0044] Specifically, the computing and processing component 52 obtains the current temperature of the laser light source module 10 collected by the temperature sensor, and outputs a corresponding voltage signal to control the temperature control component 53 to heat or cool according to the temperature difference between the current temperature and the target temperature, so that the laser light source module 10 reaches the target temperature, thereby locking the laser center wavelength emitted by the laser light source module 10 at the target center wavelength, and then controlling the light source driving component 54 to make the laser light source module 10 emit laser.

[0045] In one embodiment of the present invention, the laser detection module 40 is used to convert the detection light intensity into an electrical signal; the control module 50 includes: a collection component 51, which is connected to the laser detection module 40 and the calculation processing component 52, respectively, and is used to collect the electrical signal and amplify the electrical signal;

[0046] The calculation processing component 52 is used to convert the amplified electrical signal into a voltage signal, and control the temperature control component 53 and the light source driving component 54 to determine the temperature of the laser light source module when the absorption peak generated by the voltage signal is at the target position.

[0047] Specifically, the acquisition component 51 collects the electrical signal converted by the laser detection module 40 from the transmitted laser, and amplifies the electrical signal. The calculation and processing component 52 converts the amplified electrical signal into a digital signal to obtain a voltage signal, and controls the temperature control component 53 and the light source driving component 54 through the output voltage signal to determine the temperature of the laser light source module 10 when the absorption peak generated by the voltage signal is at the target position.

[0048] In one embodiment of the present invention, the computing processing component 52 is used to:

[0049] Based on the maximum temperature value, control the temperature control component to reduce the temperature of the laser light source module with a first preset temperature step, and control the light source driving component to perform continuous scanning from a minimum current to a maximum current, and obtain the laser wavelength range output by the laser light source module and the laser intensity range detected by the laser detection module during the scanning process;

[0050] If the target absorption wavelength is not within the laser wavelength range, returning to the step of controlling the temperature control component to reduce the temperature of the laser light source module by a first preset temperature step;

[0051] If the target absorption wavelength is within the laser wavelength range, the temperature control component is controlled to reduce the temperature of the laser light source module with a second preset temperature step, and the light source driving component is controlled to continuously scan from the minimum current to the maximum current until the absorption peak generated by the voltage signal is scanned to the center point of the laser wavelength range. The temperature step control of the laser light source module is stopped and the temperature of the laser light source module at this time is recorded to obtain the target temperature.

[0052] In the embodiment of the present invention, the wavelength temperature tuning coefficient of the laser light source module 10 is , the wavelength current tuning coefficient is , the spectral target absorption wavelength of the gas to be tested is .

[0053] In an embodiment of the present invention, the computing and processing component 52 outputs a voltage signal Vmin-Vmax, corresponding to the temperature control target Tmin-Tmax of the temperature control component 53, and at the same time controls the light source driving component 54 to output an Imin-Imax linear driving current signal, driving the laser light source module 10 to output laser light intensity, and the laser passes through the open measuring gas chamber 20 without the gas to be measured and the closed gas block 30, and the laser detection module 40 generates a detection light intensity G.

[0054] Specifically, Figure 2 As shown, the automatic calibration process of the central wavelength is as follows: the calculation processing component 52 can control the temperature control component 53 to gradually control the temperature Ti=Tmax-i*Δt starting from the maximum temperature value Tmax with Δt as a step, until it is determined that the temperature of the laser light source module is at the target position when the absorption peak generated by the gas in the closed gas block 30 is at the target position. Exemplarily, under the temperature condition of T1=Tmax-Δt, the light source driving component 54 continuously scans from Imin-Imax (that is, controls the light source driving component 54 to continuously output the driving current of Imin-Imax), and the linear wavelength range of the laser light source module 10 is - The laser detection module 40 detects the linear laser intensity as Gmin-Gmax, where Gmin corresponds to , Gmax corresponds to . Determine the target absorption wavelength Is it within the laser wavelength range? - Inside.

[0055] If the target absorbs the wavelength Not in the laser wavelength range - Under the temperature condition of T2=Tmax-2*Δt, the light source driving component 54 is controlled to continuously scan from Imin-Imax, and the linear wavelength range of the laser light source module 10 is - The laser detection module 40 detects the linear laser intensity as Gmin-Gmax, where Gmin corresponds to , Gmax corresponds to . And determine the target absorption wavelength Is it within the laser wavelength range? - Inside.

[0056] When the target absorbs the wavelength exist - If the laser detection module 40 is within the range, the positions corresponding to the linear laser intensities Gmin and Gmax generated by the laser detection module 40 are extracted to obtain Pos(Gmax) and Pos(Gmin). Based on the scanning center wavelength Pos(ΔGi)=[Pos(Gmax)-Pos(Gmin)] / 2+Pos(Gmin), determine whether Pos(ΔGi) is 50%. If Pos(ΔGi) is equal to 50%, stop the temperature step and lock the temperature control target. If the target absorbs the wavelength exist - range, but Pos (ΔGi) is not equal to 50%, resulting in an absorption peak effect such as Figure 3 As shown, the absorption intensity is ΔGi corresponding to the target absorption wavelength Further controlling the temperature control component 53 to reduce the temperature of the laser light source module 10 with a second preset temperature step, and controlling the light source driving component 54 to continuously scan from the minimum current to the maximum current, the following can be obtained: Figure 4 The absorption peak diagram shown in Figure 2 shows that the target absorption wavelength Not scanned to - The temperature control component 53 is controlled again to reduce the temperature of the laser light source module with a second preset temperature step, and the light source driving component 54 is controlled to continuously scan from the minimum current to the maximum current until Pos (ΔGk) = 50%. When Pos (ΔGk) = 50%, it indicates that the target absorption wavelength Scan to - The center point between Gmin and Gmax is obtained by adjusting the absorption intensity ΔGi to the middle position between Gmin and Gmax. Figure 5The absorption peak diagram is shown. Scan the central wavelength Pos (ΔGi) = [Pos (Gmax) - Pos (Gmin)] / 2 + Pos (Gmin), and control the temperature step by Δt. When i = k, Pos (ΔGk) = 50%, stop the temperature step and lock the temperature control target to Tmax-Δt*k. It should be noted that at the target absorption wavelength exist - When the target absorption wavelength is within the range, the Δt value can be gradually reduced with the number of steps until the target absorption wavelength is Scan to - The center point between.

[0057] It should be noted that Gmax and Gmin are actually the minimum light intensity and maximum light intensity signals detected by the laser detection module 40 under the same step-by-step temperature and current scanning, which belongs to a linear continuous process. By extracting the maximum and minimum values ​​of the light intensity, Pos (Gmax) and Pos (Gmin) can be determined, which are the start signal and end signal of the current scanning.

[0058] It should be noted that the calculation processing component 52 of the embodiment of the present invention can also control the temperature control component 53 to gradually control the temperature Ti=Tmin+i*Δt starting from Tmin with Δt as the step. When i=k, Pos(ΔGk)=50%, the temperature step is stopped and the temperature control target is locked to Tmin+i*Δt.

[0059] Working process of the laser gas measurement device of the embodiment of the present invention, center wavelength self-calibration process, real-time detection of center wavelength by absorption peak position In the case of an offset, when |Pos(ΔGk)-50%|>Δp, the self-calibration process is started to re-lock the center wavelength. It should be noted that the center wavelength automatic calibration and self-calibration process of the laser gas measurement device in the embodiment of the present invention are the same, and the self-calibration process will not be repeated here.

[0060] In one embodiment of the present invention, determining the concentration of the gas to be measured according to the detected light intensity may include:

[0061] Obtaining a first optical path length and a calibration light intensity of the laser transmitted through the open measuring gas chamber, wherein the calibration light intensity is the light intensity generated by the laser detection module 40 based on the laser transmitted through the closed gas block when the open measuring gas chamber is not diffused with the gas to be measured;

[0062] The concentration of the gas to be measured is calculated based on the relationship between the concentration and the first optical path length, the calibration light intensity and the detection light intensity.

[0063] Specifically, when calculating the concentration of the gas to be measured, the first optical path length and the calibration light intensity are obtained, and the concentration of the gas to be measured is calculated using the relationship between the concentration and the first optical path length, the calibration light intensity and the detection light intensity.

[0064] In one embodiment of the present invention, the relationship between the concentration and the first optical path length, the calibration light intensity and the detection light intensity is expressed as follows:

[0065]

[0066] in, Indicates concentration, represents a constant, represents the first optical path length, represents the detected light intensity, Indicates the calibrated light intensity.

[0067] Specifically, the laser light intensity emitted by the laser light source module 10 is I0, the incident light intensity of the closed gas block is It, the exit light intensity of the closed gas block is Ip, the length of the open measurement gas chamber (first optical path length) is L1, and the length of the closed gas block (second optical path length) is L0. When there is no gas to be measured in the open measurement gas chamber 20, It=I0, and the laser detection module 40 detects that the projected light intensity is Ip1.

[0068] According to the Beer-Lambert law, the concentration of the closed gas mass is The formula is: (1)

[0069] When the gas to be measured exists in the open measuring gas chamber 20, the laser detection module 40 detects that the projected light intensity is Ip2 and the incident light intensity of the closed gas block is It2.

[0070] Concentration of closed gas mass The formula is: (2)

[0071] Gas concentration to be measured The formula is: (3)

[0072] Derived from Formula 2 and Formula 3: (4)

[0073] Derived from Formula 1 and Formula 4: ,in, is the concentration of the gas to be measured, L1 is the first optical path length, the projected light intensity detected by the laser detection module 40 is Ip2, and the projected light intensity detected by the laser detection module 40 is Ip1.

[0074] In one embodiment of the present invention, the closed gas block is made of a light-transmitting material and is filled with a gas to be tested at a preset concentration.

[0075] For example, when detecting whether domestic natural gas is fully burned and whether the CO gas concentration exceeds the standard, CO gas with a known concentration may be filled inside the closed gas block 30 .

[0076] The laser gas measuring device of the embodiment of the present invention places a standard closed gas block 30 in the measuring optical path, and self-calibration and concentration measurement do not require switching, and can perform real-time self-checking and real-time measurement, with high efficiency and reliability. In addition, the laser gas measuring device of the embodiment of the present invention can scan the center wavelength in a step-by-step manner and quickly lock the center wavelength through the characteristic gas wavelength absorption peak effect during laser center wavelength offset detection and self-calibration, and can also dynamically detect and correct the center wavelength.

[0077] The laser gas measuring device of the embodiment of the present invention can conveniently and quickly detect and calibrate the deviation of the laser center wavelength while ensuring the measurement of concentration.

[0078] The invention provides a laser gas measurement method.

[0079] The laser gas measurement method in the embodiment of the present invention is used in the laser gas measurement device as described above.

[0080] Figure 6 FIG. 1 is a flow chart of a laser gas measurement method according to an embodiment of the present invention. Figure 6 As shown, the laser gas measurement method may include:

[0081] S101, controlling the laser light source module to output laser light of a target central wavelength;

[0082] S102, obtaining the detection light intensity generated by the laser detection module after the laser is transmitted through the open measurement air chamber and the closed air block;

[0083] S103, determining the concentration of the gas to be measured according to the detected light intensity, and calibrating the center wavelength of the laser output by the laser light source module, wherein the target center wavelength is determined by the gas to be measured.

[0084] In one embodiment of the present invention, controlling the laser light source module to output laser light of a target central wavelength includes:

[0085] The temperature control component is controlled so that the laser detection module is at a target temperature, so that the laser light source module outputs laser light of a target central wavelength, wherein the target temperature is the temperature of the laser light source module when the computing and processing component controls the temperature control component and the light source driving component so that the absorption peak generated by the electrical signal is at a target position.

[0086] In one embodiment of the present invention, calibrating the central wavelength of the laser output by the laser light source module includes:

[0087] collecting the electrical signal converted from the detection light intensity and amplifying the electrical signal;

[0088] The amplified electrical signal is converted into a voltage signal, and the temperature control component and the light source driving component are controlled to determine the temperature of the laser light source module when the absorption peak generated by the voltage signal is at a target position.

[0089] In one embodiment of the present invention, controlling the temperature control component and the light source driving component to determine the temperature of the laser light source module when the absorption peak generated by the voltage signal is at a target position includes:

[0090] Based on the maximum temperature value, control the temperature control component to reduce the temperature of the laser light source module with a first preset temperature step, and control the light source driving component to perform continuous scanning from a minimum current to a maximum current, and obtain the laser wavelength range output by the laser light source module and the laser intensity range detected by the laser detection module during the scanning process;

[0091] If the target absorption wavelength is not within the laser wavelength range, returning to the step of controlling the temperature control component to reduce the temperature of the laser light source module by a first preset temperature step;

[0092] If the target absorption wavelength is within the laser wavelength range, the temperature control component is controlled to reduce the temperature of the laser light source module with a second preset temperature step, and the light source driving component is controlled to continuously scan from the minimum current to the maximum current until the absorption peak generated by the voltage signal is scanned to the center point of the laser wavelength range, and the temperature of the temperature control component at this time is recorded to obtain the target temperature.

[0093] In one embodiment of the present invention, determining the concentration of the gas to be measured according to the detected light intensity includes:

[0094] Acquire a first optical path length and a calibration light intensity of the laser transmitted through the open measurement gas chamber, wherein the calibration light intensity is the light intensity generated by the laser detection module based on the laser transmitted through the closed gas block when the open measurement gas chamber is not diffused with the gas to be measured;

[0095] The concentration of the gas to be measured is calculated based on the relationship between the concentration and the first optical path length, the calibration light intensity and the detection light intensity.

[0096] It should be noted that other specific implementations of the laser gas measurement device provided in the embodiment of the present invention may refer to other specific implementations of the laser gas measurement method in the above embodiment of the present invention.

[0097] The laser gas measurement method in the embodiment of the present invention eliminates the need to switch between self-calibration and concentration measurement, thereby simplifying the operation process of self-calibration while ensuring the stability of gas measurement.

[0098] The present invention provides a computer-readable storage medium.

[0099] In this embodiment, a computer program is stored on a computer-readable storage medium. When the computer program is executed by a processor, the laser gas measurement method as described above is implemented.

[0100] The invention provides a controller.

[0101] In this embodiment, the controller includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the laser gas measurement method as described above is implemented.

[0102] Figure 7 4 is a structural block diagram of a controller according to an embodiment of the present invention.

[0103] like Figure 7 As shown, the controller 500 includes: a processor 501 and a memory 503. The processor 501 and the memory 503 are connected, such as through a bus 502. Optionally, the controller 500 may also include a transceiver 504. It should be noted that in actual applications, the transceiver 504 is not limited to one, and the structure of the controller 500 does not constitute a limitation on the embodiments of the present invention.

[0104] The processor 501 may be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. The processor 501 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0105] The bus 502 may include a path to transmit information between the above components. The bus 502 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The bus 502 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0106] The memory 503 is used to store a computer program corresponding to the laser gas measurement method of the above embodiment of the present invention, and the computer program is controlled and executed by the processor 501. The processor 501 is used to execute the computer program stored in the memory 503 to implement the contents shown in the above method embodiment. Figure 7 The controller 500 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0107] The computer-readable storage medium and controller in the embodiments of the present invention utilize the above-mentioned laser gas measurement method to eliminate the need to switch between self-calibration and concentration measurement, thereby simplifying the operation process of self-calibration while ensuring the stability of gas measurement.

[0108] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0109] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0110] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0111] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0112] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0113] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0114] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0115] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A laser gas measuring device, characterized in that: The device comprises a laser light source module, an open measurement air chamber, a closed air block and a laser detection module. In a first direction, the axes of the laser light source module, the open measurement air chamber, the closed air block and the laser detection module are in a straight line. The device further comprises: a control module connected to the laser light source module and the laser detection module, and used to control the laser light source module to output laser light of a target central wavelength, obtain the detection light intensity generated by the laser detection module after the laser light passes through the open measurement gas chamber and the closed gas block, determine the concentration of the gas to be measured according to the detection light intensity, and calibrate the central wavelength of the laser light output by the laser light source module, wherein the target central wavelength is determined by the gas to be measured; The control module includes a computing and processing component, a temperature control component and a light source driving component, wherein the computing and processing component is connected to the temperature control component and the light source driving component respectively, and the temperature control component and the light source driving component are connected to the laser light source module respectively, and the computing and processing component is used to control the temperature control component to make the laser light source module at a target temperature so that the laser light source module outputs laser light of a target central wavelength; Wherein, the calculation and processing component is used to: based on the maximum temperature value, control the temperature control component to reduce the temperature of the laser light source module with a first preset temperature step, and control the light source driving component to perform continuous scanning from the minimum current to the maximum current, and obtain the laser wavelength range output by the laser light source module and the laser intensity range detected by the laser detection module during the scanning process; if the target absorption wavelength is not within the laser wavelength range, return to execute the step of controlling the temperature control component to reduce the temperature of the laser light source module with a first preset temperature step; if the target absorption wavelength is within the laser wavelength range, control the temperature control component to reduce the temperature of the laser light source module with a second preset temperature step, and control the light source driving component to perform continuous scanning from the minimum current to the maximum current until the absorption peak generated by the voltage signal is scanned to the center point of the laser wavelength range, record the temperature of the temperature control component at this time, and obtain the target temperature, wherein the voltage signal is obtained by amplifying the electrical signal generated by the laser detection module by the calculation and processing component.

2. The laser gas measuring device according to claim 1, characterized in that: The target temperature is the temperature of the laser light source module when the absorption peak generated by the electrical signal converted from the detection light intensity is at the target position, wherein the computing and processing component controls the target temperature by controlling the temperature control component and the light source driving component.

3. The laser gas measuring device according to claim 2, characterized in that: The laser detection module is used to convert the detection light intensity into an electrical signal; the control module includes: A collection component, connected to the laser detection module and the calculation processing component respectively, for collecting electrical signals and amplifying the electrical signals; The calculation processing component is used to convert the amplified electrical signal into a voltage signal, and control the temperature control component and the light source driving component to determine the temperature of the laser light source module when the absorption peak generated by the voltage signal is at a target position.

4. The laser gas measuring device according to claim 1, characterized in that: The computing and processing component is used to: Acquire a first optical path length and a calibration light intensity of the laser transmitted through the open measurement gas chamber, wherein the calibration light intensity is the light intensity generated by the laser detection module based on the laser transmitted through the closed gas block when the open measurement gas chamber is not diffused with the gas to be measured; The concentration of the gas to be measured is calculated based on the relationship between the concentration and the first optical path length, the calibration light intensity and the detection light intensity.

5. The laser gas measuring device according to claim 4, characterized in that: The relationship between the concentration and the first optical path length, the calibration light intensity and the detection light intensity is expressed as follows: in, represents the concentration, represents a constant, represents the first optical path length, represents the detected light intensity, represents the calibrated light intensity.

6. The laser gas measuring device according to claim 1, characterized in that: The closed gas block is made of a light-transmitting material and is filled with a gas to be tested of a preset concentration.

7. A laser gas measurement method, characterized in that: For use in a laser gas measurement device as claimed in any one of claims 1 to 6, the method comprising: Control the laser light source module to output laser light of the target central wavelength; Acquire the detection light intensity generated by the laser detection module after the laser is transmitted through the open measurement air chamber and the closed air block; The concentration of the gas to be measured is determined according to the detected light intensity, and the central wavelength of the laser output by the laser light source module is calibrated, wherein the target central wavelength is determined by the gas to be measured; wherein the calibrating the central wavelength of the laser output by the laser light source module comprises: controlling the temperature control component to make the laser light source module at the target temperature so that the laser light source module outputs the laser with the target central wavelength; Wherein, the temperature control component and the light source driving component are controlled to determine the temperature of the laser light source module when the absorption peak generated by the voltage signal is at the target position, including: based on the maximum temperature value, controlling the temperature control component to reduce the temperature of the laser light source module with a first preset temperature step, and controlling the light source driving component to perform continuous scanning from the minimum current to the maximum current, and obtaining the laser wavelength range output by the laser light source module and the laser intensity range detected by the laser detection module during the scanning process; if the target absorption wavelength is not within the laser wavelength range, returning to execute the step of controlling the temperature control component to reduce the temperature of the laser light source module with the first preset temperature step; If the target absorption wavelength is within the laser wavelength range, the temperature control component is controlled to reduce the temperature of the laser light source module with a second preset temperature step, and the light source driving component is controlled to continuously scan from the minimum current to the maximum current until the absorption peak generated by the voltage signal is scanned to the center point of the laser wavelength range, and the temperature of the temperature control component at this time is recorded to obtain the target temperature, wherein the voltage signal is obtained by amplifying the electrical signal generated by the laser detection module.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the laser gas measurement method according to claim 7 is implemented.

9. A controller, comprising a memory and a processor, wherein a computer program is stored in the memory, characterized in that: When the computer program is executed by the processor, the laser gas measurement method according to claim 7 is implemented.

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