CN115015149A - Laser infrared gas concentration detection method and system based on dynamic absorption lines - Google Patents

Laser infrared gas concentration detection method and system based on dynamic absorption lines Download PDF

Info

Publication number
CN115015149A
CN115015149A CN202210480618.7A CN202210480618A CN115015149A CN 115015149 A CN115015149 A CN 115015149A CN 202210480618 A CN202210480618 A CN 202210480618A CN 115015149 A CN115015149 A CN 115015149A
Authority
CN
China
Prior art keywords
voltage
absorption line
value
strategy
real
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202210480618.7A
Other languages
Chinese (zh)
Other versions
CN115015149B (en
Inventor
陈海永
武传伟
张华杰
冯山虎
王婷
贾林涛
冉顺杰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hanwei Electronics Group Corp
Original Assignee
Hanwei Electronics Group Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hanwei Electronics Group Corp filed Critical Hanwei Electronics Group Corp
Priority to CN202210480618.7A priority Critical patent/CN115015149B/en
Publication of CN115015149A publication Critical patent/CN115015149A/en
Application granted granted Critical
Publication of CN115015149B publication Critical patent/CN115015149B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
    • G01N21/3504—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing gases, e.g. multi-gas analysis
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/01—Arrangements or apparatus for facilitating the optical investigation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/01—Arrangements or apparatus for facilitating the optical investigation
    • G01N2021/0106—General arrangement of respective parts
    • G01N2021/0112—Apparatus in one mechanical, optical or electronic block
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Abstract

The invention provides a laser infrared gas concentration detection method and a system based on dynamic absorption lines, wherein the method comprises the following steps: when the laser infrared gas concentration is detected, the microprocessor reads a real-time environment temperature signal T outside the semiconductor laser, and determines an absorption line adjustment strategy according to the real-time environment temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at the switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; by analogy, at the switching temperature threshold T N‑2 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T N‑1 When the strategy is executed, executing the (N-1) absorption line strategy; when the real-time environment temperature signal T is larger than a switching temperature threshold value T N‑1 Then the nth absorption line strategy is executed. The invention canWhether gas to be detected leaks can be detected quickly and accurately in a severe environment.

Description

Laser infrared gas concentration detection method and system based on dynamic absorption lines
Technical Field
The invention relates to the technical field of laser infrared gas detectors, in particular to a laser infrared gas concentration detection method and system based on dynamic absorption lines.
Background
Common combustible gas leakage detection methods include electrochemical methods, catalytic combustion methods, solid electrolyte methods, infrared spectrum absorption methods, and the like. The infrared spectrum is called as the fingerprint of a compound, has the advantages of high analysis speed, low cost, no sample consumption, easy on-line measurement and the like, and the basic theoretical basis of the infrared spectrum absorption method is the Lambert beer law.
It should be noted that, in the technical field of laser infrared gas detectors, each gas molecule has a fixed absorption spectrum, and only when the central wavelength output by the semiconductor laser is tuned to the absorption peak of the gas to be detected, the light emitted by the semiconductor laser is absorbed by the gas to be detected, and the concentration of the gas to be detected can be calculated by inversion by analyzing the change of the light intensity.
The gas to be detected comprises various gases such as methane, ethylene, propane, isobutane, methane chloride and the like; among them, a hydrocarbon mixture mainly containing methane is a main component of natural gas. The natural gas reserves in China are abundant, the distribution geographical environment is complex, the pipeline running time is prolonged along with the improvement of gas transmission pipelines such as western gas transmission, eastern faith line and acerola and the popularization of natural gas, but the natural gas pipeline leakage events are increased due to the aging of the pipelines, the corrosion of soil, the stress of stratum, the damage of construction and the like. Once the natural gas pipeline leaks, the safe and stable supply of urban basic energy can be seriously influenced on one hand, and the natural gas leaked into the atmospheric environment endangers the ecological safety, and on the other hand, due to the flammable and explosive characteristics, the natural gas leakage can cause combustion and explosion, seriously threatens the personal safety of common people and causes huge property loss.
Because the gas leakage area of the natural gas pipeline is located in the dangerous environment of an industrial field, detection personnel are inconvenient to directly contact the natural gas pipeline in a close range, and therefore, the infrared absorption spectrum gas sensing technology and the laser telemetering technology are combined to carry out detection necessarily. At present, the existing laser gas monitoring equipment adopts a fixed absorption line mode, and the use temperature range is generally-20 ℃ to 50 ℃; however, gas pipelines such as west-east gas transmission, faithful line and puckery-ninglan are likely to be in severe environments such as extremely hot or extremely cold, and therefore, a system capable of rapidly and accurately detecting whether natural gas leaks or not in severe environments is urgently needed.
In order to solve the above problems, people are always seeking an ideal technical solution.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides a laser infrared gas concentration detection method and system based on dynamic absorption lines.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the invention provides a laser infrared gas concentration detection method based on dynamic absorption lines, which comprises the following steps:
before leaving the factory, carrying out concentration calibration under N item standard absorption lines according to the type of the gas to be detected and the type of the laser, and setting N-1 switching temperature thresholds corresponding to the N item standard absorption lines;
when the laser infrared gas concentration is detected, the microprocessor reads a real-time environment temperature signal T outside the semiconductor laser, and determines an absorption line adjustment strategy according to the real-time environment temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at the switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; by analogy with thatAt a switching temperature threshold T N-2 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T N-1 When the strategy is executed, executing the (N-1) absorption line strategy; when the real-time environment temperature signal T is larger than a switching temperature threshold value T N-1 When the strategy is executed, executing the Nth absorption line strategy;
each absorption line strategy comprises an adjustment rule I and an adjustment rule II; the target absorption lines corresponding to each absorption line strategy are different, and the target absorption lines under different adjustment rules I correspond to different target voltage digital quantity value ranges;
when the ith absorption line strategy is executed, the laser modulation current is adjusted to be the modulation current I i Selecting one of the regulation rule I and the regulation rule II to be started according to the input instruction until the output central wavelength of the semiconductor laser is regulated in the central wavelength locking value interval W i The absorption line is adjusted to the ith absorption line of the gas to be measured;
when the adjusting rule I is started, the microprocessor executes:
step A1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: digital quantity of voltage D DOWN Voltage value V less than or equal to RES Digital quantity D of not more than voltage up (ii) a If not, go to step A2;
step A2, at said voltage value V RES < the voltage digital quantity D DOWN At a predetermined interval a 1 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than maximum value V of variable terminal voltage pMAX If yes, go to step A1; if not, the voltage V of the changed voltage after increasing p = V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 2 Dynamic reduction of fixed end voltage V of temperature controller N And go to step a 1;
at said voltage value V RES Said voltage digital quantity D up At a predetermined interval a 3 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V of the transformer is judged p Whether or not it is greater than the minimum value V of the variable-end voltage pMIN If yes, go to step A1; if not, the voltage V of the changed voltage after reduction p = V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 4 Dynamically increasing fixed end voltage V of temperature controller N And go to step a 1;
when the adjusting rule II is started, the microprocessor executes:
step B1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: voltage digital quantity D TDOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage Tup If not, go to step B2;
step B2, at the voltage value V RES < the voltage digital quantity D TDOWN At a predetermined interval a 5 Dynamically increasing variable-terminal voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step B1; if not, the voltage V at the increased variable terminal p =V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 6 Dynamic reduction of fixed end voltage V of temperature controller N And go to step B1;
at said voltage value V RES Said voltage digital quantity D Tup At a predetermined interval a 7 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V of the transformer is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step B1; if not, the voltage V of the changed voltage after reduction p =V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 8 Dynamically increasing fixed end voltage V of temperature controller N And go to step B1. .
The invention provides a laser infrared gas concentration detection system based on dynamic absorption lines, which comprises a preprocessing unit, an absorption line strategy management unit and an absorption line strategy execution unit, wherein the absorption line strategy execution unit comprises an execution unit I, an execution unit II and an execution unit III,
the preprocessing unit is used for calibrating the concentration under the N item label absorption lines according to the type of the gas to be detected and the type of the laser before delivery, and setting N-1 switching temperature thresholds corresponding to the N item label absorption lines;
the absorption line strategy management unit is used for reading a real-time environment temperature signal T outside the semiconductor laser when detecting the laser infrared gas concentration, and determining an absorption line adjustment strategy according to the real-time environment temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at a switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; by analogy, at the switching temperature threshold T N-2 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T N-1 When the strategy is executed, executing the (N-1) absorption line strategy; when the real-time environment temperature signal T is larger than a switching temperature threshold value T N-1 When the strategy is executed, executing the Nth absorption line strategy; each absorption line strategy comprises an adjusting rule I and an adjusting rule II; the target absorption lines corresponding to each absorption line strategy are different, and the target absorption lines under different adjustment rules I correspond to different target voltage digital quantity value ranges;
the execution unit I is used for adjusting the laser modulation current to be the modulation current I when the ith absorption line strategy is executed i Selecting one of the regulation rule I and the regulation rule II to be started according to the input instruction until the output central wavelength of the semiconductor laser is regulated in the central wavelength locking value interval W i The absorption line is adjusted to the ith absorption line of the gas to be measured;
the execution unit ii is configured to, when the adjustment rule i is enabled, execute:
step A1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: voltage digital quantity D DOWN Voltage value V is less than or equal to RES Digital quantity D of voltage less than or equal to up (ii) a If not, go to step A2;
step A2, at said voltage value V RES < number of said voltagesWord quantity D DOWN At a predetermined interval a 1 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than maximum value V of variable terminal voltage pMAX If yes, go to step A1; if not, the voltage V of the changed voltage after increasing p = V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 2 Dynamic reduction of fixed end voltage V of temperature controller N And go to step a 1;
at said voltage value V RES Said voltage digital quantity D up At a predetermined interval a 3 Dynamic reduction of variable-end voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step A1; if not, the voltage V of the changed voltage after reduction p = V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 4 Dynamically increasing fixed end voltage V of temperature controller N And go to step a 1;
the execution unit iii is configured to, when the adjustment rule ii is enabled, execute:
step B1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: voltage digital quantity D TDOWN Voltage value V less than or equal to RES Digital quantity D of not more than voltage Tup If not, go to step B2;
step B2, at the voltage value V RES < the voltage digital quantity D TDOWN At a predetermined interval a 5 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than maximum value V of variable terminal voltage pMAX If yes, go to step B1; if not, the voltage V of the changed voltage after increasing p =V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 6 Dynamic reduction of fixed end voltage V of temperature controller N And go to step B1;
at said voltage value V RES Digital quantity D of said voltage Tup At a predetermined interval a 7 Dynamic reduction of variable-end voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step B1; if not, the voltage V of the changed voltage after reduction p =V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 8 Dynamically increasing the voltage V at the fixed end of the temperature controller N And go to step B1.
A third aspect of the present invention provides a laser infrared gas concentration detection apparatus based on dynamic absorption lines, which includes a memory, a processor, and a laser infrared gas concentration detection program based on dynamic absorption lines, stored in the memory and executable on the processor, wherein when the laser infrared gas concentration detection program based on dynamic absorption lines is executed by the processor, the steps of the laser infrared gas concentration detection method based on dynamic absorption lines as described above are implemented.
A fourth aspect of the present invention provides a readable storage medium having stored thereon instructions that, when executed by a processor, implement the steps of the dynamic absorption line-based laser infrared gas concentration detection method as described above.
Compared with the prior art, the invention has prominent substantive characteristics and remarkable progress, particularly:
1) in the invention, in an industrial field, a microprocessor automatically and dynamically adjusts an absorption line strategy according to a real-time environment temperature signal T outside a semiconductor laser so as to enable an absorption line of a changed laser infrared gas concentration detection system to be matched with a field environment; after determining which absorption line strategy to execute, the microprocessor selects and starts the adjusting rule I and the adjusting rule II based on the input instruction, and selects and starts the adjusting rule I and the adjusting rule II according to the real-time voltage value V of the thermistor in the semiconductor laser RES Variable end voltage and fixed end voltage V of dynamic temperature controller N Therefore, the gas to be detected in the severe environment can be detected quickly and accurately;
2) after the adjustment rule I is confirmed to be executed, the microprocessor also detects whether the adjustment of the absorption line is successful, the voltage digital quantity value range corresponding to the adjustment rule I in the ith absorption line strategy is matched with the real-time voltage digital quantity value range, the adjustment of the absorption line is judged to be successful, and the current concentration of the gas to be detected can be calculated and generated continuously; if not, judging that the adjustment of the absorption line fails, not calculating to generate the current concentration of the gas to be detected continuously, and generating a first feedback message;
3) after confirming that the regulation rule II is finished, the microprocessor also detects whether the absorption line regulation is successful or not, and the real-time center wavelength is W' i Central wavelength locking value interval W corresponding to regulation rule II in ith absorption line strategy i When the gas concentration is matched with the absorption line, the absorption line is judged to be successfully adjusted, and the current concentration of the generated gas to be detected can be continuously calculated; and if not, judging that the adjustment of the absorption line fails, and generating a second feedback message without continuously calculating the current concentration of the generated gas to be detected.
Drawings
FIG. 1 is a first flow chart of the method for detecting the concentration of a laser infrared gas based on dynamic absorption lines according to the present invention;
FIG. 2 is a second flow chart of the method for detecting the concentration of a laser infrared gas based on dynamic absorption lines according to the present invention;
FIG. 3 is a flow chart of dynamically adjusting the reference voltage temperature control based on the fixed absorption line of the reference gas cell according to the present invention;
FIG. 4 is a flow chart of the present invention for dynamically adjusting the temperature control of the reference voltage at fixed absorption without a reference gas cell;
fig. 5 is a schematic diagram of the structure of a semiconductor laser.
Detailed Description
The technical solution of the present invention is further described in detail by the following embodiments.
It should be noted that, the laser gas detection is based on the molecular spectrum theory, and different molecules have unique absorption lines, and the lines have parameters such as line intensity, broadening and linearity, and depend on the changes of pressure and temperature. The method selects proper detection spectral lines and spectral line parameters, is the premise of gas detection, the near infrared spectrum covers a wide spectral range, has very many absorption spectral lines (absorption lines), each gas has an individual absorption peak, is easy to distinguish, and is most widely used in the field of gas detection.
As shown in the attached figure 5, a semiconductor laser 2 and a thermistor 3 are positioned in a constant temperature cavity 1, and a temperature controller (TEC driver) 4, a microprocessor 5 and a temperature sensor 6 are positioned outside the constant temperature cavity 1;
one end of the thermistor 3 is connected with an RT + pin of the semiconductor laser 2, and the other end of the thermistor 3 is connected with the microprocessor 5 and used for collecting temperature signals in the constant-temperature cavity 1 in real time and transmitting the temperature signals to the microprocessor 5; a first terminal of the TEC driving unit 4 is connected to a TEC + pin of the semiconductor laser 2, a second terminal of the TEC driving unit 4 is connected to a TEC-pin of the semiconductor laser 2, and a third terminal of the TEC driving unit 4 is connected to the microprocessor 5, and is configured to receive an adjustment instruction from the microprocessor 5 to adjust output power of the TEC driving unit 4, thereby changing a temperature in the constant temperature cavity 1; the temperature sensor 6 is connected with the microprocessor 5 and used for acquiring a temperature signal (the current environment temperature T of the equipment) outside the constant temperature cavity 1 in real time and transmitting the temperature signal to the microprocessor 5.
Example 1
A laser infrared gas concentration detection method based on dynamic absorption lines, the method comprising the steps of:
before leaving the factory, carrying out concentration calibration under N item standard absorption lines according to the type of the gas to be detected and the type of the laser, and setting N-1 switching temperature thresholds corresponding to the N item standard absorption lines;
when the laser infrared gas concentration is detected, the microprocessor reads a real-time environment temperature signal T outside the semiconductor laser, and determines an absorption line adjustment strategy according to the real-time environment temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at the switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; by analogy, at the switching temperature threshold T N-2 Not more than the real-time environment temperature signal T is not more than the switching temperatureThreshold value T N-1 Executing the (N-1) th absorption line strategy; when the real-time environment temperature signal T is larger than a switching temperature threshold value T N-1 When the strategy is executed, executing the Nth absorption line strategy;
each absorption line strategy comprises an adjustment rule I and an adjustment rule II; the target absorption lines corresponding to each absorption line strategy are different, and the target absorption lines under different adjustment rules I correspond to different target voltage digital quantity value ranges;
when the ith absorption line strategy is executed, the laser modulation current is adjusted to be the modulation current I i Selecting one of the regulation rule I and the regulation rule II to be started according to the input instruction until the output central wavelength of the semiconductor laser is regulated in the central wavelength locking value interval W i The absorption line is adjusted to the ith absorption line of the gas to be measured;
when the adjusting rule I is started, the microprocessor executes:
step A1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: voltage digital quantity D DOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage up (ii) a If not, go to step A2;
step A2, at said voltage value V RES < the voltage digital quantity D DOWN At a predetermined interval a 1 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than maximum value V of variable terminal voltage pMAX If yes, go to step A1; if not, the voltage V at the increased variable terminal p = V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 2 Dynamic reduction of fixed end voltage V of temperature controller N And go to step a 1;
at said voltage value V RES Said voltage digital quantity D up At a predetermined interval a 3 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable-end voltage pMIN If yes, go to step A1; if not, the voltage V of the changed voltage after reduction p = V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 4 Dynamically increasing the voltage V at the fixed end of the temperature controller N And go to step a 1;
when the adjusting rule II is started, the microprocessor executes:
step B1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: digital quantity of voltage D TDOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage Tup If not, go to step B2;
step B2, at the voltage value V RES < the voltage digital quantity D TDOWN At a predetermined interval a 5 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step B1; if not, the voltage V of the changed voltage after increasing p =V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 6 Dynamic reduction of fixed end voltage V of temperature controller N And go to step B1;
at said voltage value V RES Digital quantity D of said voltage Tup At a predetermined interval a 7 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step B1; if not, the voltage V of the changed voltage after reduction p =V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 8 Dynamically increasing fixed end voltage V of temperature controller N And go to step B1.
Wherein, the variable terminal voltage V of the temperature controller p Is preset, and the initial value of the fixed terminal voltage of the thermostat is set to V0.
Specifically, the voltage digital quantity D in the step a1 DOWN Sum voltage digital quantity D up The voltage regulating circuits are arranged corresponding to the regulating rules I one by one, and the regulating rules I under different absorption line strategies correspond to different voltage numbersWord quantity D DOWN Sum voltage digital quantity D up (ii) a Before leaving factory, configuring and finishing absorption line strategy, regulation rule I and voltage digital quantity D DOWN Sum voltage digital quantity D up The mapping relation between the two modules is stored in a storage module in advance;
the voltage digital quantity D in the step B1 TDOWN Sum voltage digital quantity D Tup The voltage digital quantity D is set corresponding to the adjustment rules II one by one, and the adjustment rules II under different absorption line strategies correspond to different voltage digital quantities D TDOWN Sum voltage digital quantity D Tup (ii) a Before leaving factory, configuring and finishing absorption line strategy, regulation rule II and voltage digital quantity D TDOWN Sum voltage digital quantity D Tup And the mapping relation between the two is stored in the storage module in advance.
In order to further improve the detection accuracy and ensure low power consumption, the present embodiment further detects whether the adjustment of the absorption line is successful, and when it is determined that the adjustment of the absorption line is successful, the calculation is continued to obtain the concentration of the gas to be detected, which is the prior art and is not described herein again; when it is determined that the adjustment of the absorption line has failed, the calculation is not continued, the gas concentration is not outputted, or even if the gas concentration is outputted, the gas concentration needs to be marked and explained for rough reference.
Further, after confirming that the execution of the adjustment rule i is completed, the microprocessor also detects whether the absorption line adjustment is successful:
extracting second harmonic of the reference gas circuit signal to obtain a second harmonic maximum value of the reference gas circuit signal;
extracting a real-time voltage digital value range according to a pre-stored mapping relation between the maximum value of the second harmonic and the voltage digital value range;
and judging whether the value range of the voltage digital quantity corresponding to the adjustment rule I in the ith absorption line strategy is matched with the value range of the real-time voltage digital quantity, if not, judging that the adjustment of the absorption line fails, and generating a first feedback message.
Further, after confirming that the execution of the adjustment rule ii is completed, the microprocessor also detects whether the adjustment of the absorption line is successful:
reading real-time center wavelength W 'output by semiconductor laser' i Judging the real-time central wavelength W' i The central wavelength locking value interval W corresponding to the adjustment rule II in the ith absorption line strategy i And if the two feedback messages are not matched, judging that the adjustment of the absorption line fails, and generating a second feedback message.
It should be noted that different molecules have different frequency infrared spectra, which is the basis for judging different gas molecule types; therefore, in order to solve the problem of monitoring various gas types such as methane, ethylene, propane, isobutane, methyl chloride and the like, the invention sets a polling mechanism, sequentially calls switching temperature thresholds corresponding to different gas types such as methane, ethylene, propane, isobutane, methyl chloride and the like according to a preset sequence in a detection period, and determines an absorption line adjustment strategy according to the relation between the called switching temperature thresholds and the real-time environment temperature signal T.
In one embodiment, taking the gas type to be measured as CH4 and the laser type as a semiconductor near infrared laser as an example, two absorption lines are set, and the first absorption line of the gas to be measured is configured as 1651nm switching temperature threshold T 1 The second absorption line of the gas to be measured is configured to 1654nm, switching the temperature threshold T 1 Is 35 ℃; as shown in fig. 2, the ambient temperature signal T outside the cavity is less than the switching temperature threshold T 1 Executing a1 st absorption line strategy, and adjusting the absorption line of the laser infrared gas concentration detection system to be a first absorption line of the gas to be detected; the ambient temperature signal T outside the cavity is greater than or equal to a switching temperature threshold T 1 Then, the 2 nd absorption line strategy is executed, and the absorption line of the laser infrared gas concentration detection system is adjusted to the second absorption line of the gas to be detected.
In particular, the interval a 1 The interval a 2 The interval a 3 The interval a 4 The gap a 5 The interval a 6 The interval a 7 And the interval a 8 The steps are the same and are all 0.01V to 0.5V, for example, 0.01V, 0.05V, 0.15V or 0.25V, etc., and can be carried out according to actual requirementsAnd (5) modifying.
The interval a can be adjusted according to actual requirements 1 The gap a 2 The gap a 3 The gap a 4 The interval a 5 The interval a 6 The interval a 7 And the interval a 8 And the change ranges of the central wavelengths of the lasers corresponding to the two absorption lines of the CH4 after the absorption lines are adjusted are ensured not to be crossed, so that the detection precision is improved.
In one embodiment, three absorption lines are set, taking the gas type to be measured as CH4 and the laser type as a semiconductor mid-infrared laser as an example; as shown in fig. 1, when detecting the laser infrared gas concentration, the microprocessor reads a real-time ambient temperature signal T outside the semiconductor laser, and determines an absorption line adjustment strategy according to the real-time ambient temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at the switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; when the real-time environment temperature signal T is larger than a switching temperature threshold value T 2 Then, the 3 rd absorption line strategy is executed.
It should be noted that the number of target absorption lines is N, the number of switching temperature thresholds is N-1, and the number of absorption line strategies is N; the above two embodiments are examples, and in practical applications, the number of target absorption lines can be set according to the type of gas to be measured and the type of laser.
Example 2
The embodiment provides a laser infrared gas concentration detection system based on dynamic absorption lines, which comprises a preprocessing unit, an absorption line strategy management unit and an absorption line strategy execution unit, wherein the absorption line strategy execution unit comprises an execution unit I, an execution unit II and an execution unit III,
the preprocessing unit is used for calibrating the concentration under the N item label absorption lines according to the type of the gas to be detected and the type of the laser before delivery, and setting N-1 switching temperature thresholds corresponding to the N item label absorption lines;
the absorption line strategy management unit is used for reading a real-time environment temperature signal T outside the semiconductor laser when detecting the laser infrared gas concentration, and determining an absorption line adjustment strategy according to the real-time environment temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at a switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; by analogy, at the switching temperature threshold T N-2 Is less than or equal to the real-time environment temperature signal T and is less than or equal to the switching temperature threshold value T N-1 When the strategy is executed, executing the (N-1) absorption line strategy; when the real-time environment temperature signal T is larger than a switching temperature threshold value T N-1 When the strategy is executed, executing the Nth absorption line strategy; each absorption line strategy comprises an adjusting rule I and an adjusting rule II; the target absorption lines corresponding to each absorption line strategy are different, and the target absorption lines under different adjustment rules I correspond to different target voltage digital quantity value ranges;
the execution unit I is used for adjusting the laser modulation current to be the modulation current I when the ith absorption line strategy is executed i Selecting one of the regulation rule I and the regulation rule II to be started according to the input instruction until the output central wavelength of the semiconductor laser is regulated in the central wavelength locking value interval W i The absorption line is adjusted to the ith absorption line of the gas to be measured;
the execution unit ii is configured to, when the adjustment rule i is enabled, execute:
step A1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: voltage digital quantity D DOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage up (ii) a If not, go to step A2;
step A2, at the voltage value V RES < the voltage digital quantity D DOWN At a predetermined interval a 1 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step A1;if not, the voltage V at the increased variable terminal p = V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 2 Dynamic reduction of fixed end voltage V of temperature controller N And go to step a 1;
at said voltage value V RES Digital quantity D of said voltage up At a predetermined interval a 3 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step A1; if not, the voltage V of the changed voltage after reduction p = V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 4 Dynamically increasing fixed end voltage V of temperature controller N And go to step a 1;
the execution unit iii is configured to, when the adjustment rule ii is enabled, execute:
step B1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: digital quantity of voltage D TDOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage Tup If not, go to step B2;
step B2, at the voltage value V RES < the voltage digital quantity D TDOWN At a predetermined interval a 5 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step B1; if not, the voltage V of the changed voltage after increasing p =V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 6 Dynamic reduction of fixed end voltage V of temperature controller N And go to step B1;
at said voltage value V RES Digital quantity D of said voltage Tup At a predetermined interval a 7 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step B1; if not, thenVoltage V at reduced voltage change p =V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 8 Dynamically increasing fixed end voltage V of temperature controller N And go to step B1.
Further, the laser infrared gas concentration detection system based on dynamic absorption lines is characterized by further comprising an absorption line adjustment and confirmation unit I, which is used for:
after the adjustment rule I is confirmed to be executed, extracting second harmonic of the reference gas path signal to obtain a second harmonic maximum of the reference gas path signal;
extracting a real-time voltage digital value range according to a pre-stored mapping relation between the maximum value of the second harmonic and the voltage digital value range;
and judging whether the value range of the voltage digital quantity corresponding to the adjustment rule I in the ith absorption line strategy is matched with the value range of the real-time voltage digital quantity, if not, judging that the adjustment of the absorption line fails, and generating a first feedback message.
Further, the laser infrared gas concentration detection system based on dynamic absorption lines is characterized by further comprising an absorption line adjustment confirming unit II, which is used for:
after confirming that the regulation rule II is executed, reading the real-time central wavelength W 'output by the semiconductor laser' i Judging the real-time central wavelength W' i The central wavelength locking value interval W corresponding to the adjustment rule II in the ith absorption line strategy i And if the two feedback messages are not matched, judging that the adjustment of the absorption line fails, and generating a second feedback message.
The laser temperature control method generally includes that a voltage at one end of a fixed temperature controller (TEC driver) 4, for example, a TEC-pin of the temperature controller (TEC driver) is a fixed voltage after 2.5V passes through a voltage dividing resistor; in addition, the voltage at the other end of the temperature controller (TEC driver) 4 is also limited by a voltage range, for example, the TEC + pin of the temperature controller (TEC driver) can load 3.3V at most, and this TEC driving method has the disadvantage that the variation range of the voltage and the current output between the TEC + and the TEC-is wired and cannot output a large current, which further causes the limitation of the output power of the TEC driver and influences the temperature control of the laser. Therefore, the invention combines the laser temperature control method of dynamically adjusting the reference voltage on the basis of changing the absorption line, thereby realizing the rapid and accurate detection of whether the natural gas leaks in the severe environment and having the advantage of reducing the power consumption of the laser.
The principle of laser temperature control for dynamically adjusting reference voltage is as follows: after changing the absorption line, the absorption line is kept unchanged; under normal environment, a TEC-pin of the temperature controller (TEC driver) 4 outputs a reference voltage (fixed terminal voltage V) by default through a DAC N ) Changing voltage DAC0 on TEC + pin of TEC driver (fixed terminal voltage V) N ) The output of the laser, the voltage change of the TEC + pin of the TEC driver is realized, so that the temperature control of the laser is realized; when the laser meets a severe environment or a severe place, such as an extremely cold or extremely hot environment, the voltage loaded on the TEC-pin of the temperature controller (TEC driver) 4 is gradually changed, and then the voltage change of the TEC + pin of the temperature controller (TEC driver) is combined to realize the temperature control of the wide temperature of the laser.
Example 3
This embodiment provides a specific implementation of a laser infrared gas concentration detection apparatus based on dynamic absorption lines, which includes a memory, a processor, and a laser infrared gas concentration detection program based on dynamic absorption lines, stored in the memory and executable on the processor, where when the laser infrared gas concentration detection program based on dynamic absorption lines is executed by the processor, the steps of the laser infrared gas concentration detection method based on dynamic absorption lines as in embodiment 1 are implemented.
The present example also provides an embodiment of a readable storage medium, which has stored thereon instructions that, when executed by a processor, implement the steps of the method for detecting a concentration of a laser infrared gas based on a dynamic absorption line according to example 1.
In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.
Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.
In the embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, and for example, the division of the above-described modules is only one logical functional division, and other divisions may be realized in practice, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed.
In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated module may be stored in a computer-readable storage medium if it is implemented in the form of a software functional unit and sold or used as a separate product. Based on such understanding, all or part of the flow in the method of the embodiments described above may be implemented by a computer program, which may be stored in a computer-readable storage medium and can implement the steps of the embodiments of the methods described above when the computer program is executed by a processor. The computer program includes computer program code, and the computer program code may be in a source code form, an object code form, an executable file or some intermediate form.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the invention, it is intended to cover all modifications within the scope of the invention as claimed.

Claims (8)

1. A laser infrared gas concentration detection method based on dynamic absorption lines is characterized by comprising the following steps:
before leaving the factory, carrying out concentration calibration under N item standard absorption lines according to the type of the gas to be detected and the type of the laser, and setting N-1 switching temperature thresholds corresponding to the N item standard absorption lines;
when the laser infrared gas concentration is detected, the microprocessor reads a real-time environment temperature signal T outside the semiconductor laser, and determines an absorption line adjustment strategy according to the real-time environment temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at the switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; by analogy, at the switching temperature threshold T N-2 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T N-1 When the strategy is executed, executing the (N-1) absorption line strategy; when the real-time environment temperature signal T is larger than a switching temperature threshold value T N-1 When the strategy is executed, executing the Nth absorption line strategy;
each absorption line strategy comprises an adjustment rule I and an adjustment rule II; the target absorption lines corresponding to each absorption line strategy are different, and the target absorption lines under different adjustment rules I correspond to different target voltage digital quantity value ranges;
when the ith absorption line strategy is executed, the laser modulation current is adjusted to be the modulation current I i Selecting one of the regulation rule I and the regulation rule II according to the input command until the semiconductor laser outputs the central waveThe length is adjusted in the central wavelength locking value range W i The absorption line is adjusted to the ith absorption line of the gas to be measured;
when the adjusting rule I is started, the microprocessor executes:
step A1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: voltage digital quantity D DOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage up (ii) a If not, go to step A2;
step A2, at said voltage value V RES < the voltage digital quantity D DOWN At a predetermined interval a 1 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step A1; if not, the voltage V at the increased variable terminal p = V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 2 Dynamic reduction of fixed end voltage V of temperature controller N And go to step a 1;
at said voltage value V RES Said voltage digital quantity D up At a predetermined interval a 3 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V of the transformer is judged p Whether or not it is greater than the minimum value V of the variable-end voltage pMIN If yes, go to step A1; if not, the voltage V of the changed voltage after reduction p = V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 4 Dynamically increasing fixed end voltage V of temperature controller N And go to step a 1;
when the adjusting rule II is started, the microprocessor executes:
step B1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: voltage digital quantity D TDOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage Tup If not, go to step B2;
step B2, at the voltage value V RES < the voltage digital quantity D TDOWN When the temperature of the water is higher than the set temperature,at a predetermined interval a 5 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step B1; if not, the voltage V of the changed voltage after increasing p =V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 6 Dynamic reduction of fixed end voltage V of temperature controller N And go to step B1;
at said voltage value V RES Digital quantity D of said voltage Tup At a predetermined interval a 7 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step B1; if not, the voltage V of the changed voltage after reduction p =V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 8 Dynamically increasing the voltage V at the fixed end of the temperature controller N And go to step B1.
2. The dynamic absorption line based laser infrared gas concentration detection method as claimed in claim 1, wherein after confirming that the execution of the adjustment rule i is completed, the microprocessor further detects whether the absorption line adjustment is successful:
extracting second harmonic of the reference gas circuit signal to obtain a second harmonic maximum value of the reference gas circuit signal;
extracting a real-time voltage digital value range according to a pre-stored mapping relation between the maximum value of the second harmonic and the voltage digital value range;
and judging whether the value range of the voltage digital quantity corresponding to the adjustment rule I in the ith absorption line strategy is matched with the value range of the real-time voltage digital quantity, if not, judging that the adjustment of the absorption line fails, and generating a first feedback message.
3. The dynamic absorption line based laser infrared gas concentration detection method as claimed in claim 1, wherein after confirming that the execution of the adjustment rule ii is completed, the microprocessor further detects whether the absorption line adjustment is successful:
reading real-time center wavelength W 'output by semiconductor laser' i Judging the real-time central wavelength W' i The central wavelength locking value interval W corresponding to the adjustment rule II in the ith absorption line strategy i And if not, judging that the adjustment of the absorption line fails and generating a second feedback message.
4. The utility model provides a laser infrared gas concentration detecting system based on dynamic absorption line which characterized in that: comprises a preprocessing unit, a absorption line strategy management unit and an absorption line strategy execution unit, wherein the absorption line strategy execution unit comprises an execution unit I, an execution unit II and an execution unit III,
the preprocessing unit is used for calibrating the concentration under the N item label absorption lines according to the type of the gas to be detected and the type of the laser before delivery, and setting N-1 switching temperature thresholds corresponding to the N item label absorption lines;
the absorption line strategy management unit is used for reading a real-time environment temperature signal T outside the semiconductor laser when detecting the laser infrared gas concentration, and determining an absorption line adjustment strategy according to the real-time environment temperature signal T: when the real-time environment temperature signal T is less than a switching temperature threshold value T 1 Then, the 1 st absorption line strategy is executed; at the switching temperature threshold T 1 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T 2 Then, the 2 nd absorption line strategy is executed; by analogy, at the switching temperature threshold T N-2 Not more than the real-time environment temperature signal T not more than the switching temperature threshold T N-1 When the strategy is executed, executing the (N-1) absorption line strategy; when the real-time environment temperature signal T is larger than a switching temperature threshold value T N-1 When the strategy is executed, executing the Nth absorption line strategy; each absorption line strategy comprises an adjusting rule I and an adjusting rule II; the target absorption lines corresponding to each absorption line strategy are different, and the target absorption lines under different adjustment rules I correspond to different target voltage digital quantity value ranges;
the execution unit IAdjusting the laser modulation current to the modulation current I when executing the ith absorption line strategy i Selecting one of the regulation rule I and the regulation rule II to be started according to the input instruction until the output central wavelength of the semiconductor laser is regulated in the central wavelength locking value interval W i The absorption line is adjusted to the ith absorption line of the gas to be measured;
the execution unit ii is configured to, when the adjustment rule i is enabled, execute:
step A1, reading the voltage value V of the thermistor in the laser RES And judging whether the conditions are met: digital quantity of voltage D DOWN Voltage value V is less than or equal to RES Digital quantity D of not more than voltage up (ii) a If not, go to step A2;
step A2, at said voltage value V RES < the voltage digital quantity D DOWN At a predetermined interval a 1 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step A1; if not, the voltage V of the changed voltage after increasing p = V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 2 Dynamic reduction of fixed end voltage V of temperature controller N And go to step a 1;
at said voltage value V RES Digital quantity D of said voltage up At a predetermined interval a 3 Dynamic reduction of variable terminal voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step A1; if not, the voltage V of the reduced variable terminal p = V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 4 Dynamically increasing fixed end voltage V of temperature controller N And go to step a 1;
the execution unit iii is configured to, when the adjustment rule ii is enabled, execute:
step B1, reading the voltage value V of the thermistor in the laser RES And judging whether it is fullFoot conditions: voltage digital quantity D TDOWN Voltage value V less than or equal to RES Digital quantity D of not more than voltage Tup If not, go to step B2;
step B2, at the voltage value V RES < the voltage digital quantity D TDOWN At a predetermined interval a 5 Dynamically increasing variable voltage V of temperature controller p Then, the increased voltage V at the changed terminal is judged p Whether or not it is less than the maximum value V of the voltage of the transformer pMAX If yes, go to step B1; if not, the voltage V of the changed voltage after increasing p =V pMAX And the voltage V at the fixed end of the temperature controller N ＞V NMIN At a predetermined interval a 6 Dynamic reduction of fixed end voltage V of temperature controller N And go to step B1;
at said voltage value V RES Said voltage digital quantity D Tup At a predetermined interval a 7 Dynamic reduction of variable-end voltage V of temperature controller p Then, the reduced voltage V at the changed terminal is judged p Whether or not it is greater than the minimum value V of the variable terminal voltage pMIN If yes, go to step B1; if not, the voltage V of the changed voltage after reduction p =V pMIN And the voltage V at the fixed end of the temperature controller N ＜V NMAX At a predetermined interval a 8 Dynamically increasing fixed end voltage V of temperature controller N And go to step B1.
5. The dynamic absorption line based laser infrared gas concentration detection system according to claim 4, further comprising an absorption line adjustment confirmation unit I for:
after the adjustment rule I is confirmed to be executed, extracting second harmonic of the reference gas path signal to obtain the maximum value of the second harmonic of the reference gas path signal;
extracting a real-time voltage digital value range according to a pre-stored mapping relation between the maximum value of the second harmonic and the voltage digital value range;
and judging whether the value range of the voltage digital quantity corresponding to the adjustment rule I in the ith absorption line strategy is matched with the value range of the real-time voltage digital quantity, if not, judging that the adjustment of the absorption line fails, and generating a first feedback message.
6. The dynamic absorption line based laser infrared gas concentration detection system according to claim 4, further comprising an absorption line adjustment confirmation unit II for:
after confirming that the execution of the adjustment rule II is finished, reading the real-time central wavelength W 'output by the semiconductor laser' i Judging the real-time central wavelength W' i The central wavelength locking value interval W corresponding to the adjustment rule II in the ith absorption line strategy i And if not, judging that the adjustment of the absorption line fails and generating a second feedback message.
7. The utility model provides a laser infrared gas concentration check out test set based on dynamic absorption line which characterized in that: comprising a memory, a processor and a dynamic absorption line based laser infrared gas concentration detection program stored on the memory and executable on the processor, the dynamic absorption line based laser infrared gas concentration detection program when executed by the processor implementing the steps of the dynamic absorption line based laser infrared gas concentration detection method according to any one of claims 1-3.
8. A readable storage medium having instructions stored thereon, characterized in that: the instructions when executed by the processor implement the steps of the dynamic absorption line based laser infrared gas concentration detection method of any one of claims 1 to 3.
CN202210480618.7A 2022-05-05 2022-05-05 Laser infrared gas concentration detection method and system based on dynamic absorption line Active CN115015149B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210480618.7A CN115015149B (en) 2022-05-05 2022-05-05 Laser infrared gas concentration detection method and system based on dynamic absorption line

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210480618.7A CN115015149B (en) 2022-05-05 2022-05-05 Laser infrared gas concentration detection method and system based on dynamic absorption line

Publications (2)

Publication Number Publication Date
CN115015149A true CN115015149A (en) 2022-09-06
CN115015149B CN115015149B (en) 2023-11-17

Family

ID=83068051

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210480618.7A Active CN115015149B (en) 2022-05-05 2022-05-05 Laser infrared gas concentration detection method and system based on dynamic absorption line

Country Status (1)

Country Link
CN (1) CN115015149B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117129459A (en) * 2023-10-26 2023-11-28 天津创盾智能科技有限公司 Method and system for detecting aerosol by laser-induced fluorescence

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150042991A1 (en) * 2012-02-27 2015-02-12 Siemens Aktiengesellschaft Laser Spectrometer and Method for Measuring Concentration of a Gas Component in a Measurement Gas
CN105044026A (en) * 2015-08-27 2015-11-11 安徽中科瀚海光电技术发展有限公司 Laser methane concentration measuring method based on double-spectrum absorption line and waveform matching
CN111562055A (en) * 2020-05-22 2020-08-21 北京富吉瑞光电科技有限公司 Infrared imaging and concentration detection device and method for methane gas leakage
CN111707634A (en) * 2020-06-30 2020-09-25 华南理工大学 Multi-channel gas concentration detection system and method based on mid-infrared absorption spectrum
US20210096068A1 (en) * 2019-09-30 2021-04-01 Siemens Aktiengesellschaft Method and Gas Analyzer for Measuring the Concentration of a Gas Component in a Measurement Gas

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150042991A1 (en) * 2012-02-27 2015-02-12 Siemens Aktiengesellschaft Laser Spectrometer and Method for Measuring Concentration of a Gas Component in a Measurement Gas
CN105044026A (en) * 2015-08-27 2015-11-11 安徽中科瀚海光电技术发展有限公司 Laser methane concentration measuring method based on double-spectrum absorption line and waveform matching
US20210096068A1 (en) * 2019-09-30 2021-04-01 Siemens Aktiengesellschaft Method and Gas Analyzer for Measuring the Concentration of a Gas Component in a Measurement Gas
CN111562055A (en) * 2020-05-22 2020-08-21 北京富吉瑞光电科技有限公司 Infrared imaging and concentration detection device and method for methane gas leakage
CN111707634A (en) * 2020-06-30 2020-09-25 华南理工大学 Multi-channel gas concentration detection system and method based on mid-infrared absorption spectrum

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117129459A (en) * 2023-10-26 2023-11-28 天津创盾智能科技有限公司 Method and system for detecting aerosol by laser-induced fluorescence
CN117129459B (en) * 2023-10-26 2023-12-26 天津创盾智能科技有限公司 Method and system for detecting aerosol by laser-induced fluorescence

Also Published As

Publication number Publication date
CN115015149B (en) 2023-11-17

Similar Documents

Publication Publication Date Title
CN101755487B (en) Device and method for detecting a street lamp fault
CA2846087C (en) Automatic set point adjustment system and method for engine air-fuel ratio control system
CN106969800B (en) A kind of device and method measuring gas temperature and concentration simultaneously using single spectral line
CN115015149A (en) Laser infrared gas concentration detection method and system based on dynamic absorption lines
KR101690444B1 (en) Gas turbine system, controller, and gas turbine operation method
CN107589776B (en) Maximum power point tracing method, MPPT controller and photovoltaic generating system
CN109973300A (en) Power control method and device for wind generating set
CN110195715B (en) Control method and device for adjustable guide vane of mechanical equipment and mechanical equipment
CN112462005B (en) Temperature compensation method and related product
CN112326895B (en) Sensitivity compensation method and related product
KR102139329B1 (en) Method and apparatus for monitoring solar power plant
CN112433091A (en) Real-time detection system for power consumption of chip
CN101509433B (en) Oxygen sensor deterioration emulator control deviation calibrating method based on lambda closed-loop control
CN112304885A (en) VCSEL-based adaptive multi-spectral-line CO detection system and method
CN117079442A (en) Chemical industry park hazardous chemical gas leakage diffusion monitoring system based on data analysis
CN115596988B (en) LNG gas station accuse system
CN111365138B (en) Rail pressure control method and device
CN114759557A (en) Coal-fired unit AGC adjustment performance prediction method
CN102855344A (en) Wide-band oxygen sensor algorithm checking and parameter optimizing method based on simulation
CN105446413B (en) A kind of photovoltaic DC-to-AC converter and its maximum power point tracing method and device
Ying et al. Study on the regression method of compressor map based on partial least squares regression modeling
CN113777401A (en) Distributed power supply harmonic detection method comprising inverter
Yang et al. Simulation and experimental study of diesel engine emission temperature based on tunable diode laser absorption spectroscopy
CN115387925B (en) Method and system for improving performance stability of diesel engine in high-temperature environment
CN111677597B (en) Air-fuel ratio control system of electronic fuel injection engine

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant