CN117664870A - Gas concentration detection device and method with temperature real-time compensation - Google Patents
Gas concentration detection device and method with temperature real-time compensation Download PDFInfo
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Abstract
The invention provides a gas concentration detection device and method with temperature real-time compensation, which belongs to the field of gas concentration detection, wherein the gas concentration detection device comprises: two lasers, a detector and a microprocessor; the two lasers are respectively used for emitting a first laser beam and a second laser beam to the gas to be detected; the wavelength ranges of the two lasers cover two specific absorption peak wavelengths of the gas to be detected; the detector is used for receiving a first emergent beam and a second emergent beam of the gas to be detected and converting the two emergent beams into electric signals; the microprocessor is used for calculating the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be detected according to the electric signals, correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm according to the real-time temperature of the gas to be detected, and further determining the real concentration of the gas to be detected.
Description
Technical Field
The invention relates to the field of gas concentration detection, in particular to a gas concentration detection device and method with temperature real-time compensation.
Background
The method has a crucial effect on the real-time monitoring of the gas concentration in various fields such as social production, environmental protection, scientific research and the like. And the tunable diode laser absorption spectroscopy (Tunable Diode LaserAbsorption Spectroscopy, TDLAS) technology is one of the common methods for monitoring gas concentration in real time. The TDLAS technology is a high-resolution infrared laser diagnosis technology, based on the basic principle of molecular absorption spectrum, the narrow linewidth characteristic of a tunable semiconductor laser light source is utilized, and the information such as gas concentration, temperature and the like is obtained through scanning and measurement of a single absorption spectral line fingerprint region of gas molecules, so that the TDLAS technology has the advantages of high sensitivity, high spectral resolution, good selectivity, high response speed, non-contact measurement, real-time online measurement and the like. The principle is that after laser passes through a gas medium to be detected, the laser is received by a detector, and a gas concentration value is calculated by analyzing a laser intensity signal obtained by transmitting the gas medium and utilizing a spectrum absorptivity measuring result obtained in a frequency domain, wherein the gas concentration value is shown in figure 1. The basis of the gas concentration monitoring and analyzing is that parameters in a spectrum database are marked at normal temperature, and real-time monitoring data can cause great difference of calibration results due to the fact that the monitoring temperature is very normal, so that the real-time monitoring result of the gas concentration is often severely interfered by the ambient temperature, and the uncertainty is even as high as 10% -20%.
As shown in fig. 2, when the gas concentration is unchanged due to factors such as the gas concentration and the external air pressure, the absorption intensity of the gas to be measured is reduced as the temperature increases. In practical production, gas leakage or emission often occurs in different temperature environments, so in order to better detect and monitor the accurate concentration of the gas to be measured in different temperature environments, the influence of the ambient temperature on the measurement result must be considered.
Currently, TDLAS-based gas concentration detection technologies are roughly classified into two types, one of which is to directly detect or monitor the absorption light intensity of a gas to be detected on site by using a hand-held portable gas detector so as to determine the concentration of the gas; and secondly, collecting the gas to be detected into a gas tank, and detecting the gas concentration by using off-line desk equipment when the gas is at normal temperature. The disadvantage of the two technologies is that, in the first technology, the portable gas detector is simple to operate, but the ambient temperature has a large influence on the detection result, and an accurate gas concentration result cannot be obtained. For the second detection technology, although the off-line detection mode avoids the influence of the ambient temperature on the detection result, the operation process is complex, the detection result is lagged, and real-time on-line information cannot be obtained.
In summary, a technology for accurately detecting the gas concentration in real time based on TDLAS is lacking at present.
Disclosure of Invention
The invention aims to provide a gas concentration detection device and method with temperature real-time compensation, which can detect the gas concentration in real time and improve the accuracy of gas concentration detection.
In order to achieve the above object, the present invention provides a temperature real-time compensated gas concentration detection apparatus, comprising: the device comprises a first laser, a second laser, a detector and a microprocessor;
the first laser is used for emitting a first laser beam to the gas to be detected; the second laser is used for emitting a second laser beam to the gas to be detected; the wavelength range of the first laser and the second laser covers two specific absorption peak wavelengths of the gas to be detected;
the detector is used for receiving a first emergent beam and a second emergent beam of the gas to be detected, converting the first emergent beam into a first electric signal and converting the second emergent beam into a second electric signal; the first emergent beam is a beam after the first laser beam interacts with target molecules in the gas to be detected, and the second emergent beam is a beam after the second laser beam interacts with the target molecules in the gas to be detected;
the microprocessor is connected with the detector, and is used for calculating the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be detected according to the first electric signal and the second electric signal, correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm according to the real-time temperature of the gas to be detected, and determining the real concentration of the gas to be detected according to the corrected first real-time concentration and the corrected second real-time concentration.
Optionally, the temperature real-time compensated gas concentration detection device further comprises a controller; the controller is respectively connected with the first laser, the second laser and the detector; the controller is used for controlling the first laser to emit a first laser beam, controlling the second laser to emit a second laser beam, controlling the detector to convert the first emergent beam into a first electric signal, and controlling the detector to convert the second emergent beam into a second electric signal.
Optionally, the temperature real-time compensated gas concentration detection device further comprises an amplifier; the amplifier is respectively connected with the detector and the microprocessor, and is used for amplifying the first electric signal and the second electric signal and then transmitting the amplified first electric signal and the amplified second electric signal to the microprocessor.
Optionally, the microprocessor includes:
the signal processing module is connected with the detector and used for determining a first optical signal curve according to the first electrical signal, determining a second optical signal curve according to the second electrical signal, determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the first laser according to the first optical signal curve and determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the second laser according to the second optical signal curve;
the real-time temperature calculation module is connected with the signal processing module and is used for calculating the real-time temperature of the gas to be detected according to the integral intensity of the absorption peak corresponding to the wavelength of the first laser and the integral intensity of the absorption peak corresponding to the wavelength of the second laser;
the real-time concentration calculation module is connected with the signal processing module and is used for calculating a first real-time concentration according to the integral intensity and the spectral line intensity of an absorption peak corresponding to the wavelength of the first laser and calculating a second real-time concentration according to the integral intensity and the spectral line intensity of an absorption peak corresponding to the wavelength of the second laser;
the concentration correction module is respectively connected with the real-time temperature calculation module and the real-time concentration calculation module and is used for correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm until the difference value between the corrected first real-time concentration and the corrected second real-time concentration is smaller than a set threshold value;
the real concentration determining module is connected with the concentration correcting module and is used for determining the real concentration of the gas to be detected according to the corrected first real-time concentration and the corrected second real-time concentration.
Optionally, the real-time temperature calculation module calculates the real-time temperature of the gas to be measured using formula 1/t0= aln (A1/A2) +b; wherein T0 is the real-time temperature of the gas to be measured, A1 is the integrated intensity of the absorption peak corresponding to the wavelength of the first laser, A2 is the integrated intensity of the absorption peak corresponding to the wavelength of the second laser, and a and b are both constants.
Optionally, the real-time concentration calculation module calculates the first real-time concentration using formula y1=αc10+β and calculates the second real-time concentration using formula y2=αc20+β; wherein C10 is a first real-time concentration, C20 is a second real-time concentration, α and β are constants, y1=a1/S1 (T), y2=a2/S2 (T), S1 (T) is a line intensity corresponding to a wavelength of the first laser, and S2 (T) is a line intensity corresponding to a wavelength of the second laser.
In order to achieve the above object, the present invention further provides a method for detecting a gas concentration by temperature real-time compensation, including:
transmitting a first laser beam to the gas to be measured through a first laser, and transmitting a second laser beam to the gas to be measured through a second laser; the wavelength range of the first laser and the second laser covers two specific absorption peak wavelengths of the gas to be detected;
the method comprises the steps of receiving a first emergent beam and a second emergent beam of the gas to be detected through a detector, converting the first emergent beam into a first electric signal, and converting the second emergent beam into a second electric signal; the first emergent beam is a beam after the first laser beam interacts with target molecules in the gas to be detected, and the second emergent beam is a beam after the second laser beam interacts with the target molecules in the gas to be detected;
calculating the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be measured according to the first electric signal and the second electric signal by a microprocessor, correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm according to the real-time temperature of the gas to be measured, and determining the real concentration of the gas to be measured according to the corrected first real-time concentration and the corrected second real-time concentration.
Optionally, calculating the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be measured according to the first electrical signal and the second electrical signal specifically includes:
determining a first optical signal curve according to the first electrical signal;
determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the first laser according to the first optical signal curve;
determining a second optical signal profile from the second electrical signal;
determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the second laser according to the second optical signal curve;
calculating the real-time temperature of the gas to be detected according to the integral intensity of the absorption peak corresponding to the wavelength of the first laser and the integral intensity of the absorption peak corresponding to the wavelength of the second laser;
calculating a first real-time concentration according to the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the first laser;
and calculating a second real-time concentration according to the integral intensity and the spectral line intensity of the absorption peak corresponding to the wavelength of the second laser.
Optionally, the real concentration is an average of the corrected first real-time concentration and the corrected second real-time concentration.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects: the invention uses two lasers to emit laser with two wave bands, can detect the intensity change of the light with two wavelengths after gas absorption, and realize the real-time detection of the gas temperature, then corrects the real-time concentration according to the real-time temperature by BP neural network algorithm, obtains the real concentration, improves the measurement accuracy of the gas concentration, and can accurately detect the gas concentration in real time by only depending on TDLAS, and the structure of the gas concentration detection device is simple.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a baseline light intensity fitting using light intensity of unabsorbed regions;
FIG. 2 is a graph showing the variation of absorption intensity with temperature;
FIG. 3 is a schematic diagram of a temperature real-time compensated gas concentration detection device according to the present invention;
FIG. 4 is a schematic diagram of a BP neural network;
FIG. 5 is a schematic diagram of the BP neural network output with an error of less than 1% from the real concentration;
FIG. 6 is a schematic diagram of the BP neural network output with an error of greater than or equal to 1% from the real concentration;
fig. 7 is a flow chart of a method for detecting gas concentration by temperature real-time compensation provided by the invention.
Symbol description: 1-first laser, 2-second laser, 3-detector, 4-microprocessor, 5-controller, 6-amplifier.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention aims to provide a gas concentration detection device and method capable of compensating temperature in real time, which can accurately detect gas concentration and temperature in real time by detecting gas temperature and compensating and correcting the detected concentration, thereby improving the accuracy of a gas concentration detection result.
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.
As shown in fig. 3, the gas concentration detection device with temperature real-time compensation provided by the invention comprises: a first laser 1, a second laser 2, a detector 3 and a microprocessor 4.
The first laser 1 is used for emitting a first laser beam to a gas to be measured. The second laser 2 is configured to emit a second laser beam toward the gas to be measured. The wavelength ranges of the first laser 1 and the second laser 2 cover two specific absorption peak wavelengths of the gas to be measured.
In this embodiment, the wavelengths of the two lasers are different and the emission spectrum lines do not overlap with each other, so as to improve the temperature detection accuracy. The selection of the lasers mainly surrounds the range of the emitted laser wavelength, the wavelength ranges of the two lasers are selected to cover two specific absorption peak wavelengths of the gas to be detected through the HITRAN database, and the two wavelengths should avoid the interference of water and other gases as much as possible.
The detector 3 is configured to receive the first outgoing beam and the second outgoing beam of the gas to be detected, and convert the first outgoing beam into a first electrical signal, and convert the second outgoing beam into a second electrical signal. The first emergent beam is a beam after the first laser beam interacts with target molecules in the gas to be detected, and the second emergent beam is a beam after the second laser beam interacts with the target molecules in the gas to be detected.
In the present embodiment, the detector 3 corresponds to the wavelength ranges of the first laser 1 and the second laser 2.
The microprocessor 4 is connected with the detector 3, and the microprocessor 4 is configured to calculate a real-time temperature, a first real-time concentration and a second real-time concentration of the gas to be measured according to the first electrical signal and the second electrical signal, correct the first real-time concentration and the second real-time concentration by using a BP neural network algorithm according to the real-time temperature of the gas to be measured, and determine a real concentration of the gas to be measured according to the corrected first real-time concentration and the corrected second real-time concentration.
In this embodiment, the real concentration is an average value of the corrected first real-time concentration and the corrected second real-time concentration.
Specifically, the microprocessor 4 includes: the device comprises a signal processing module, a real-time temperature calculation module, a real-time concentration calculation module, a concentration correction module and a real concentration determination module.
The signal processing module is connected with the detector 3, and is configured to determine a first optical signal curve according to the first electrical signal, determine a second optical signal curve according to the second electrical signal, determine an integrated intensity and a spectral line intensity of an absorption peak corresponding to a wavelength of the first laser 1 according to the first optical signal curve, and determine an integrated intensity and a spectral line intensity of an absorption peak corresponding to a wavelength of the second laser 2 according to the second optical signal curve.
The signal processing module processes the received electric signals to obtain an optical signal curve, and calculates information such as the intensity, the absorption area and the like of absorption peaks on the absorption spectrum line.
The real-time temperature calculation module is connected with the signal processing module and is used for calculating the real-time temperature of the gas to be detected according to the integral intensity of the absorption peak corresponding to the wavelength of the first laser 1 and the integral intensity of the absorption peak corresponding to the wavelength of the second laser 2.
Specifically, the real-time temperature calculation module calculates the real-time temperature of the gas to be measured by adopting a formula 1/t0= aln (A1/A2) +b; wherein T0 is the real-time temperature of the gas to be measured, A1 is the integrated intensity of the absorption peak corresponding to the wavelength of the first laser 1, A2 is the integrated intensity of the absorption peak corresponding to the wavelength of the second laser 2, and a and b are both constants.
The real-time concentration calculation module is connected with the signal processing module and is used for calculating a first real-time concentration according to the integral intensity and the spectral line intensity of the absorption peak corresponding to the wavelength of the first laser 1 and calculating a second real-time concentration according to the integral intensity and the spectral line intensity of the absorption peak corresponding to the wavelength of the second laser 2.
Specifically, the real-time concentration calculation module calculates the first real-time concentration using the formula y1=αc10+β and calculates the second real-time concentration using the formula y2=αc20+β; wherein C10 is a first real-time concentration, C20 is a second real-time concentration, α and β are constants, y1=a1/S1 (T), y2=a2/S2 (T), S1 (T) is a line intensity corresponding to the wavelength of the first laser 1, and S2 (T) is a line intensity corresponding to the wavelength of the second laser 2.
The concentration correction module is respectively connected with the real-time temperature calculation module and the real-time concentration calculation module, and is used for correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm until the difference value between the corrected first real-time concentration and the corrected second real-time concentration is smaller than a set threshold value.
Specifically, the real-time concentration is corrected through a BP neural network or an algorithm-optimized BP neural network model, and a corrected first real-time concentration C1t and a corrected second real-time concentration C2t are obtained. The setting of the number of nodes of the input layer, the number of hidden layers, the number of nodes of the hidden layer, the threshold value and the weight of the BP neural network is determined according to the real-time measurement condition, and the determined standard is that the error of the output result is less than 1%.
As shown in fig. 4, the BP neural network is a multi-layer feedforward network trained according to an error back propagation algorithm, and is used for function approximation, model identification classification, data compression, time sequence prediction and the like. According to the invention, a large number of samples are used for training the BP neural network, namely, the real concentration Cr of a large number of known gases is detected at different temperatures, the real-time temperature, the first real-time concentration and the second real-time concentration are calculated corresponding to each detection, the BP neural network is trained by using the samples until the error between the corrected first real-time concentration C1t and the corrected second real-time concentration C2t output by the BP neural network and the real concentration Cr is less than 1%, and a trained BP neural network model is obtained, as shown in fig. 5 and 6. The BP neural network model may thereafter be used for the actual detection process.
In the actual detection process, comparing the difference value of the corrected first real-time concentration C1t and the corrected second real-time concentration C2t output by the BP neural network, if the difference value is smaller than a set threshold value, taking the average value of the corrected first real-time concentration C1t and the corrected second real-time concentration C2t as the real concentration of the gas to be detected, otherwise, correcting the corrected first real-time concentration and the corrected second real-time concentration output by the BP neural network by adopting the real-time temperature until the difference value is smaller than the set threshold value, so that the stability and the accuracy of the corrected first real-time concentration and the corrected second real-time concentration can be ensured to the greatest extent.
The real concentration determining module is connected with the concentration correcting module and is used for determining the real concentration of the gas to be detected according to the corrected first real-time concentration and the corrected second real-time concentration.
Further, the temperature real-time compensated gas concentration detection device also comprises a controller 5. The controller 5 is respectively connected with the first laser 1, the second laser 2 and the detector 3; the controller 5 is configured to control the first laser 1 to emit a first laser beam, control the second laser 2 to emit a second laser beam, control the detector 3 to convert the first outgoing beam into a first electrical signal, and control the detector 3 to convert the second outgoing beam into a second electrical signal.
Further, the temperature real-time compensated gas concentration detection device also comprises an amplifier 6. The amplifier 6 is connected to the detector 3 and the microprocessor 4, and the amplifier 6 is configured to amplify the first electrical signal and the second electrical signal and transmit the amplified first electrical signal and the amplified second electrical signal to the microprocessor 4.
As shown in fig. 7, the method for detecting the gas concentration by temperature real-time compensation provided by the invention comprises the following steps:
step 100: a first laser beam is emitted to the gas to be measured by the first laser 1, and a second laser beam is emitted to the gas to be measured by the second laser 2. The wavelength ranges of the first laser 1 and the second laser 2 cover two specific absorption peak wavelengths of the gas to be measured.
Step 200: the detector 3 receives the first outgoing beam and the second outgoing beam of the gas to be detected, converts the first outgoing beam into a first electrical signal, and converts the second outgoing beam into a second electrical signal. The first emergent beam is a beam after the first laser beam interacts with target molecules in the gas to be detected, and the second emergent beam is a beam after the second laser beam interacts with the target molecules in the gas to be detected.
Specifically, the first laser 1 and the second laser 2 are started to emit a first laser beam and a second laser beam to the gas to be detected, and the two laser beams enter the detector 3 to collect outgoing beams after interaction between the gas to be detected and target molecules in the gas.
Step 300: the microprocessor 4 calculates the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be measured according to the first electric signal and the second electric signal, corrects the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm according to the real-time temperature of the gas to be measured, and determines the real concentration of the gas to be measured according to the corrected first real-time concentration and the corrected second real-time concentration. The real concentration is an average value of the corrected first real-time concentration and the corrected second real-time concentration.
Specifically, (1) determining a first optical signal profile from the first electrical signal.
(2) And determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the first laser 1 according to the first optical signal curve.
(3) And determining a second optical signal curve according to the second electric signal.
(4) And determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the second laser 2 according to the second optical signal curve.
(5) And calculating the real-time temperature of the gas to be measured according to the integral intensity of the absorption peak corresponding to the wavelength of the first laser 1 and the integral intensity of the absorption peak corresponding to the wavelength of the second laser 2.
(6) And calculating a first real-time concentration according to the integral intensity and the spectral line intensity of the absorption peak corresponding to the wavelength of the first laser 1.
(7) And calculating a second real-time concentration according to the integral intensity and the spectral line intensity of the absorption peak corresponding to the wavelength of the second laser 2.
The invention only depends on TDLAS to realize accurate detection of gas concentration in real time, specifically, the invention uses two lasers to emit laser beams of two wave bands, can simultaneously detect the intensity change of light rays of two wavelengths after gas absorption, and realize real-time detection of gas temperature, then corrects the concentration according to temperature by BP neural network algorithm to obtain real concentration, further improves the measurement accuracy of gas concentration, solves the problem of inaccurate gas concentration detection caused by different temperature distribution, and has simple structure and easy and convenient calculation.
In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other.
The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to assist in understanding the methods of the present invention and the core ideas thereof; also, it is within the scope of the present invention to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the invention.
Claims (9)
1. A temperature-compensated gas concentration detection apparatus, characterized in that the temperature-compensated gas concentration detection apparatus comprises: the device comprises a first laser, a second laser, a detector and a microprocessor;
the first laser is used for emitting a first laser beam to the gas to be detected; the second laser is used for emitting a second laser beam to the gas to be detected; the wavelength range of the first laser and the second laser covers two specific absorption peak wavelengths of the gas to be detected;
the detector is used for receiving a first emergent beam and a second emergent beam of the gas to be detected, converting the first emergent beam into a first electric signal and converting the second emergent beam into a second electric signal; the first emergent beam is a beam after the first laser beam interacts with target molecules in the gas to be detected, and the second emergent beam is a beam after the second laser beam interacts with the target molecules in the gas to be detected;
the microprocessor is connected with the detector, and is used for calculating the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be detected according to the first electric signal and the second electric signal, correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm according to the real-time temperature of the gas to be detected, and determining the real concentration of the gas to be detected according to the corrected first real-time concentration and the corrected second real-time concentration.
2. The temperature-compensated gas concentration detection apparatus of claim 1, further comprising a controller;
the controller is respectively connected with the first laser, the second laser and the detector; the controller is used for controlling the first laser to emit a first laser beam, controlling the second laser to emit a second laser beam, controlling the detector to convert the first emergent beam into a first electric signal, and controlling the detector to convert the second emergent beam into a second electric signal.
3. The temperature-compensated gas concentration detection apparatus of claim 1, further comprising an amplifier;
the amplifier is respectively connected with the detector and the microprocessor, and is used for amplifying the first electric signal and the second electric signal and then transmitting the amplified first electric signal and the amplified second electric signal to the microprocessor.
4. The temperature-compensated gas concentration detection apparatus of claim 1, wherein said microprocessor comprises:
the signal processing module is connected with the detector and used for determining a first optical signal curve according to the first electrical signal, determining a second optical signal curve according to the second electrical signal, determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the first laser according to the first optical signal curve and determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the second laser according to the second optical signal curve;
the real-time temperature calculation module is connected with the signal processing module and is used for calculating the real-time temperature of the gas to be detected according to the integral intensity of the absorption peak corresponding to the wavelength of the first laser and the integral intensity of the absorption peak corresponding to the wavelength of the second laser;
the real-time concentration calculation module is connected with the signal processing module and is used for calculating a first real-time concentration according to the integral intensity and the spectral line intensity of an absorption peak corresponding to the wavelength of the first laser and calculating a second real-time concentration according to the integral intensity and the spectral line intensity of an absorption peak corresponding to the wavelength of the second laser;
the concentration correction module is respectively connected with the real-time temperature calculation module and the real-time concentration calculation module and is used for correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm until the difference value between the corrected first real-time concentration and the corrected second real-time concentration is smaller than a set threshold value;
the real concentration determining module is connected with the concentration correcting module and is used for determining the real concentration of the gas to be detected according to the corrected first real-time concentration and the corrected second real-time concentration.
5. The temperature-compensated gas concentration detection apparatus according to claim 4, wherein the real-time temperature calculation module calculates the real-time temperature of the gas to be measured using formula 1/t0= aln (A1/A2) +b; wherein T0 is the real-time temperature of the gas to be measured, A1 is the integrated intensity of the absorption peak corresponding to the wavelength of the first laser, A2 is the integrated intensity of the absorption peak corresponding to the wavelength of the second laser, and a and b are both constants.
6. The temperature-compensated gas concentration detection apparatus according to claim 4, wherein the real-time concentration calculation module calculates the first real-time concentration using formula y1=αc10+β and calculates the second real-time concentration using formula y2=αc20+β; wherein C10 is a first real-time concentration, C20 is a second real-time concentration, α and β are constants, y1=a1/S1 (T), y2=a2/S2 (T), S1 (T) is a line intensity corresponding to a wavelength of the first laser, and S2 (T) is a line intensity corresponding to a wavelength of the second laser.
7. The method for detecting the gas concentration by temperature real-time compensation is characterized by comprising the following steps of:
transmitting a first laser beam to the gas to be measured through a first laser, and transmitting a second laser beam to the gas to be measured through a second laser; the wavelength range of the first laser and the second laser covers two specific absorption peak wavelengths of the gas to be detected;
the method comprises the steps of receiving a first emergent beam and a second emergent beam of the gas to be detected through a detector, converting the first emergent beam into a first electric signal, and converting the second emergent beam into a second electric signal; the first emergent beam is a beam after the first laser beam interacts with target molecules in the gas to be detected, and the second emergent beam is a beam after the second laser beam interacts with the target molecules in the gas to be detected;
calculating the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be measured according to the first electric signal and the second electric signal by a microprocessor, correcting the first real-time concentration and the second real-time concentration by adopting a BP neural network algorithm according to the real-time temperature of the gas to be measured, and determining the real concentration of the gas to be measured according to the corrected first real-time concentration and the corrected second real-time concentration.
8. The method for detecting the concentration of the gas by temperature real-time compensation according to claim 7, wherein the calculating the real-time temperature, the first real-time concentration and the second real-time concentration of the gas to be detected according to the first electric signal and the second electric signal specifically comprises:
determining a first optical signal curve according to the first electrical signal;
determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the first laser according to the first optical signal curve;
determining a second optical signal profile from the second electrical signal;
determining the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the second laser according to the second optical signal curve;
calculating the real-time temperature of the gas to be detected according to the integral intensity of the absorption peak corresponding to the wavelength of the first laser and the integral intensity of the absorption peak corresponding to the wavelength of the second laser;
calculating a first real-time concentration according to the integral intensity and spectral line intensity of an absorption peak corresponding to the wavelength of the first laser;
and calculating a second real-time concentration according to the integral intensity and the spectral line intensity of the absorption peak corresponding to the wavelength of the second laser.
9. The method according to claim 7, wherein the real concentration is an average value of the corrected first real concentration and the corrected second real concentration.
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