Gas analyzer mixed gas concentration detection and correction method and system

Abstract

The invention relates to a gas analyzer mixed gas concentration detection and correction method and system, and the method comprises the steps: building the concentration range of each gas component according to the actually measured concentration value of the mixed gas, selecting the maximum value of the concentration range of each gas component, and carrying out the normalization processing of the reference concentration of the mixed gas and the standard concentration of a to-be-corrected gas; and establishing a correction coefficient equation by taking the normalized reference concentration of the mixed gas as an independent variable and taking the normalized standard concentration of the to-be-corrected gas as a dependent variable, so that the to-be-corrected gas is compensated and corrected on the basis of the standard concentration. The system comprises a light source, a measuring cell, a spectrograph, a data acquisition module, a data analysis module and a concentration correction module. The gas concentration value measured by the gas analyzer can be corrected, the actual measurement error is reduced, and the gas concentration detection accuracy is improved.

Description

Technical Field

[0001] The invention relates to a gas analyzer, in particular to a mixed gas concentration detection and correction method and system for a gas analyzer, belonging to the technical field of environmental detection. Background Art

[0002] A gas analyzer is a device for online monitoring of gas concentration. Currently, many gas analyzers use DOAS technology (differential absorption spectroscopy algorithm) for concentration detection. The basic principle of DOAS technology is to use the absorption cross-section of the gas to be tested to identify the gas and invert the gas concentration based on the absorption intensity.

[0003] However, in actual applications, interference factors such as temperature changes, pressure changes, and hardware non-idealities will introduce errors. Tests have found that, especially during mixed gas concentration detection, the error between the measured gas concentration value and the actual concentration value is large, which greatly affects the accuracy of gas concentration detection. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides a mixed gas concentration detection and correction method and system for a gas analyzer, which calibrates the gas concentration value measured by the gas analyzer, reduces the actual measurement error, and improves the accuracy of gas concentration detection.

[0005] The present invention discloses a method for detecting and correcting the concentration of mixed gases of a gas analyzer, comprising the following steps:

[0006] S1. The mixed gas to be detected is passed into the measuring cell, and the gas analyzer obtains the measured concentration values ​​of n gas components, and determines the calibration concentration range of each gas component according to the measured concentration values;

[0007] S2, respectively select m1, m2, ..., m in the calibration concentration range of the 1st, 2nd, ..., nth gas component of the mixed gas. n standard concentration values, forming m1*m2*····*m n Mixed gases with different concentration combinations;

[0008] S3, m1*m2*····*m n Mixed gases of various concentration combinations are sequentially introduced into the gas analyzer for ventilation testing to obtain m1*m2*····*m n Group reference concentration value;

[0009] S4, sequentially measure the mixed gas m1*m2*····*m n The reference concentration values ​​of the group are normalized to obtain the mixed gas m1*m2*····*m n group normalized reference concentration value;

[0010] S5. For the i-th (1≤i≤n) gas component to be calibrated in the mixed gas, m i The standard concentration values ​​are normalized to obtain the m of the i-th gas component to be corrected. i Normalized standard concentration value;

[0011] S6, according to m1*m2*····*m n The normalized reference concentration value and m of the i-th gas component to be corrected i Normalized standard concentration values ​​are used to establish a polynomial fitting equation to obtain the fitting coefficient solution;

[0012] S7, establish the correction parameter equation Y=f(X1, X2, ..., X n ) and stored in a gas analyzer;

[0013] S8. Normalize the measured concentration values ​​of the n gas components of the mixed gas, substitute the normalized measured concentration values ​​into the correction parameter equation and then perform a denormalization process to obtain the concentration value of the i-th gas component to be corrected in the mixed gas after compensation correction.

[0014] Specifically, in step S4, the mixed gas m1*m2*····*m n The reference concentration values ​​of the group were normalized as follows:

[0015] The maximum values ​​of the calibration concentration ranges of the first, second, ..., nth gas components of the mixed gas are taken respectively, and the reference concentration values ​​of the gas components of the mixed gas are normalized;

[0016] Specifically, in step S5, the m of the i-th (1≤i≤n) gas component to be calibrated in the mixed gas is i The standard concentration values ​​are normalized as follows:

[0017] Take the maximum value of the calibration concentration range of the i-th gas component to be calibrated, and then calculate the m i The standard concentration values ​​were normalized.

[0018] Specifically, in step S6, the polynomial fitting steps are as follows:

[0019] m1*m2*····*m n The concentration values ​​of the 1st, 2nd, ..., nth gas components in the group normalized reference concentration value are the independent variables X1, X2, ..., X n , with m of the i-th gas component to be corrected i Normalized standard concentration values ​​are repeated m1*…*m i-1 *m i+1 *…*m nThe dependent variable Y is used to establish a polynomial fitting equation.

[0020] Optionally, in step S6, the method for obtaining the fitting coefficient solution includes constructing the fitting polynomial into the form of a linear equation system of Ax=b, and solving the linear equation system by the least squares method to obtain the following solution:

[0021] x=(A′A) -1 A′b.

[0022] Optionally, in step S6, the method for obtaining the fitting coefficient solution includes constructing the fitting polynomial into the form of a linear equation system Ax=b, and using a singular value decomposition method to solve the linear equation system, performing singular value decomposition A=USV′ on A, and obtaining the following solution:

[0023] x=V(S\(U'b)).

[0024] Specifically, the normalization and denormalization processing steps in step S8 are as follows:

[0025] Take the maximum values ​​of the calibration concentration range of the first, second, ..., nth gas components of the mixed gas respectively, normalize the measured concentration values ​​of each gas component, and obtain the normalized measured concentration values ​​of each gas component

[0026] Will Substitute the correction parameter equation Y = f(X1, X2, ..., X n ),get Take the maximum value of the calibration concentration range of the i-th gas component to be calibrated in the mixed gas, Perform an anti-normalization process to obtain the concentration value of the i-th gas component to be corrected after compensation correction.

[0027] A mixed gas concentration detection and correction system for a gas analyzer includes a light source, a measuring cell, a spectrometer, a data acquisition module, a data analysis module, and a concentration correction module. The light source emits light that passes through the gas in the measuring cell and is received by the spectrometer. The spectrometer converts the collected optical signal into a digital signal and sends it to the data acquisition module. The data acquisition module is connected to the data analysis module and the concentration correction module respectively.

[0028] The data acquisition module is used to collect the measured concentration data of each component of the mixed gas to be detected and the reference concentration data of each component of the reference mixed gas; the data analysis module is used to establish a correction parameter equation based on the reference concentration value of each component of the reference mixed gas and the standard concentration value and pre-store it in the concentration correction module; the concentration correction module is used to process and correct the measured concentration values ​​of each component of the mixed gas to be detected; the process of establishing the correction parameter equation and processing and correcting the measured concentration values ​​of each component of the mixed gas to be detected is operated according to the steps of the gas analyzer mixed gas concentration detection and correction method.

[0029] The present invention establishes a concentration range of each gas component according to the measured concentration value of the mixed gas, and at the same time selects the maximum value of the concentration range of each gas component to normalize the reference concentration of the mixed gas and the standard concentration of the gas to be calibrated, and establishes a correction coefficient equation with the reference concentration of the mixed gas after normalization as the independent variable and the standard concentration of the gas to be calibrated after normalization as the dependent variable, so that the gas to be calibrated is compensated and corrected based on the standard concentration, thereby effectively reducing the error between the measured gas concentration value and the actual concentration value, and improving the accuracy of gas concentration detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Flow chart of the method of the present invention;

[0031] Figure 2 is the value of the parameter A of the linear equation system in a specific embodiment;

[0032] Figure 3 is the value of parameter b of the linear equation system in a specific embodiment;

[0033] Figure 4 A schematic diagram of a mixed gas concentration detection and correction system for a gas analyzer provided by the present invention. DETAILED DESCRIPTION

[0034] In order to explain the present invention more clearly, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0035] The specific parameters in this embodiment are based on the example of introducing a mixed gas to be tested consisting of high-concentration SO2 and low-concentration NO.

[0036] like Figure 1 As shown, a method for detecting and correcting the concentration of mixed gas in a gas analyzer comprises the following steps:

[0037] S1. The mixed gas to be detected is passed into the measuring cell, and the gas analyzer obtains the measured concentration value of each gas component, and determines the calibration concentration range of each gas component according to the measured concentration value;

[0038] To verify the effectiveness of this method, this embodiment uses a mixed gas with known concentrations of each gas component as the mixed gas to be detected. Specifically, the concentration combinations of 8000 SO2 and 600 NO, 8000 SO2 and 400 NO, 8000 SO2 and 300 NO, 8000 SO2 and 200 NO, 1500 SO2 and 50 NO (unit: mg / m 3 ) Five groups of mixed gases, the gas analyzer obtained the measured NO concentration of the first group of mixed gases was 504.8 mg / m 3The concentration error is 15.87%. The measured concentration of NO in the second mixed gas is 344.1, and the concentration error is 13.97%. The measured concentration of NO in the third mixed gas is 259.60 mg / m 3 The concentration error is 13.47%. The measured concentration of NO in the fourth group of mixed gas is 175.0 mg / m 3 The concentration error is 12.50%. The measured concentration of NO in the fifth group of mixed gas is 49.0 mg / m 3 , the concentration error is 2%;

[0039] It can be seen that in the detection process of high-concentration SO2 and low-concentration NO mixed gas, the measured concentration error of low-concentration NO is relatively large. Therefore, in this embodiment, NO is used as the gas component to be calibrated, and the calibration concentration range of SO2 is established as [1500, 8000] according to the concentration of the above-mentioned gas components, and the calibration concentration range of NO is established as [50, 600] (unit: mg / m 3 ).

[0040] S2, respectively select m1, m2, ..., m in the calibration concentration range of the 1st, 2nd, ..., nth gas component of the mixed gas. n standard concentration values, forming m1*m2*····*m n Mixed gases with different concentration combinations;

[0041] In this embodiment, five standard concentration values ​​are selected in the calibration concentration range of SO2: 8000, 5000, 3000, 2000, and 1500, and six standard concentration values ​​are selected in the calibration concentration range of NO: 600, 400, 300, 200, 100, and 50, forming 30 concentration combinations of SO2 and NO mixed gases: (8000, 600), (5000, 600), (3000, 600), (2000, 600), (1500, 600), (8000, 400), (5000, 400), (3000, 400), (2000, 400), (1500, 400 0)、(8000、300)、(5000、300)、(3000、300)、(2000、300)、(1500、300)、(8000、200)、(5000、200)、(3000、200)、(2000、200)、(1500、200)、(8000、100)、(5000、100)、(3000、100)、(2000、100)、(1500、100)、(8000、50)、(5000、50)、(3000、50)、(2000、50)、(1500、50)(Unit: mg / m 3 );

[0042] S3, m1*m2*····*m n Mixed gases of various concentration combinations are sequentially introduced into the gas analyzer for ventilation testing to obtain mixed gases m1*m2*····*m n Group reference concentration value;

[0043] In this embodiment, ventilation tests are performed in sequence according to 30 concentration combinations of SO2 and NO mixed gases, and 30 groups of reference concentration values ​​are obtained: (8057.4, 504.8), (5044.2, 574.6), (3031.2, 608.1), (2024.9, 616.6), (1520.1, 619.0), (8043.7, 344.1), (5036.7, 385.4), (3028.8, 404.8), (2023.9, 409.7), (1520.1, 411.0), (8024.1, 259.6), (5028.8, 289.0), (3021.4, 302.1), (2018. 2,305.6), (1516.6, 306.7), (8002.7, 175.0), (5014.1, 192.2), (3020.3, 200.9), (2024.6, 203.3), (1522.6, 203.1), (7987.6, 88.4), (4999.3, 95.6), (3014.3, 99.7), (2016.6, 100.4), (1517.9, 100.5), (7982.9, 44.4), (5001.2, 46.7), (3009.4, 48.5), (2017.3, 49.0), (1518.9, 49.0) (Unit: mg / m 3 ).

[0044] S4, sequentially measure the mixed gas m1*m2*····*m n The reference concentration values ​​of the group were normalized to obtain m1*m2*····*m n group normalized reference concentration value;

[0045] Specifically, the maximum values ​​of the calibration concentration ranges of the first, second, ..., nth gas components of the mixed gas are taken respectively, and the reference concentration values ​​of the gas components of the mixed gas are normalized;

[0046] In this embodiment, the maximum value of the SO2 correction concentration range is 8000 (unit: mg / m 3 ), normalize the reference concentration values ​​of SO2 in the 30 reference concentration values, and take the maximum value of the NO correction concentration range of 600 (unit: mg / m 3), the reference concentration value of NO in the 30 groups of reference concentration values ​​was normalized, and the 30 groups of reference concentration values ​​of SO2 and NO mixed gas after normalization were obtained: (1.0072, 0.8413), (0.6305, 0.9577), (0.3789, 1.0135), (0.2531, 1.0277), (0.1900, 1.0317), (1.0055, 0.5735), (0.6296, 0.6423), (0.3786, 0.6747), (0.2530, 0.6828), (0.1900, 0.6850), (1.0030, 0.4327), (0.6286, 0.4817), (0.3777, 0.5035), (0.25 23, 0.5093), (0.1896, 0.5112), (1.0003, 0.2917), (0.6268, 0.3203), (0.3775, 0.3348), (0.2531, 0.3388), (0.1903, 0.3385), (0.9985, 0.1473), (0.6249, 0. 1593)、(0.3768,0.1662)、(0.2521,0.1673)、(0.1897,0.1675)、(0.9979,0.0740)、(0.6252,0.0778)、(0.3762,0.0808)、(0.2522,0.0817)、(0.1899,0.0817)

[0047] S5. For the i-th (1≤i≤n) gas component to be calibrated in the mixed gas, m i The standard concentration values ​​are normalized to obtain the m of the i-th gas component to be corrected. i Normalized standard concentration value;

[0048] Specifically, take the maximum value of the calibration concentration range of the i-th gas component to be calibrated, and then calculate the m i The standard concentration values ​​were normalized.

[0049] In this embodiment, the maximum value of the NO correction concentration range is 600 (unit: mg / m 3 ), the six standard concentration values ​​of NO in the mixed gas of SO2 and NO were normalized in turn to obtain six normalized standard concentration values ​​of NO in the mixed gas of SO2 and NO: 1, 0.6667, 0.50000, 0.3333, 0.1667, 0.0833;

[0050] S6, according to m1*m2*…*m n The normalized reference concentration value and m of the i-th gas component to be corrected iNormalized standard concentration values ​​are used to establish a polynomial fitting equation to obtain the fitting coefficient solution;

[0051] Specifically, m1*m2*…*m n The concentration values ​​of the 1st, 2nd, ..., nth gas components in the group normalized reference concentration value are the independent variables X1, X2, ..., X n , with m of the i-th gas component to be corrected i Normalized standard concentration values ​​are repeated m1*…*m i-1 *m i+1 *…*m n The second is the dependent variable Y, and a polynomial fitting equation is established;

[0052] The method for obtaining the fitting coefficient solution includes constructing the fitting polynomial into the form of a linear equation system Ax=b, and solving the linear equation system by the least square method to obtain the following solution:

[0053] x=(A′A) -1 A′b.

[0054] The singular value decomposition method can also be used to solve the linear equations. A is decomposed into A = USV' and the solution is as follows:

[0055] x=V(S\(U'b)).

[0056] In this embodiment, the steps of establishing a polynomial fitting equation and obtaining a fitting coefficient solution are as follows:

[0057] In the first step, 30 groups of normalized reference concentration values ​​of SO2 [1.0072, 0.6305, 0.3789, 0.2531, 0.1900, 1.0055, 0.6296, 0.3786, 0.2530, 0.1900, 1.0030, 0.6286, 0.3777, 0.2523, 0.1896, 1.0003, 0.6286, 0.3775, 0.2531, 0.1903, 0.9985, 0.6249, 0.3768, 0.2521, 0.1897, 0.9979, 0.6252, 0.3762, 0.2522, 0.1899] were used as independent variables. X1, 30 groups of normalized reference concentration values ​​of NO [0.8413, 0.9577, 1.0135, 1.0277, 1.0317, 0.5735, 0.6423, 0.6747, 0.6828, 0.6850, 0.4327, 0.4817, 0.5035, 0.5093, 0.5112, 0.2917, 0.3203, 0.3348, 0.3388, 0.3385, 0.1473, 0.1593, 0.1662, 0.1673, 0.1675, 0.0740, 0.0778, 0.0808, 0.0817, 0.0817] were used as independent variables X2;

[0058] In the second step, take the six standard concentration values ​​of NO after normalization: 1, 0.6667, 0.50000, 0.3333, 0.1667, 0.0833, and repeat them 5 times to form the dependent variable Y = [1, 1, 1, 1, 1, 0.6667, 0.6667, 0.6667, 0.6667, 0.6667, 0.5000, 0.5000, 0.5000,

[0059] 0.5000, 0.5000, 0.3333, 0.3333, 0.3333, 0.3333, 0.3333, 0.1667, 0.1667, 0.1667, 0.1667, 0.1667, 0.0833, 0.0833, 0.0833, 0.0833, 0.0833],

[0060] The third step is to fit the polynomial as follows:

[0061] Y=a 00 +a 10 X1+a 01 X2+a 20 X1 2 +a 11 X1X2+a 02 X2 2 +a 21 X1 2X2+a 12 X1X2 2 +a 22 X1 2 X2 2 ;

[0062] Step 4: Construct the fitting polynomial into the form of Ax=b linear equation system, A 30×9 、b 30×1 like Figure 2 and Figure 3 As shown;

[0063] Step 5: Solve the linear equation system A 30×9 x 9×1 =b 30×1 , and obtain the fitting coefficient solution as follows:

[0064] Solving the linear equations by the least squares method, we get the following solution:

[0065] x=(A′A) -1 A′b.

[0066] The singular value decomposition method is used to solve the linear equations. A is decomposed into A = USV' and the solution is as follows:

[0067] x=V(S\(U'b)).

[0068] The fitting coefficient solution is obtained as:

[0069] x=[0.0401,-0.1452,0.8259,0.1102,0.5709,0.1138,-0.3019,-0.5340,0.5203] T , that is, a 00 =0.0401,a 10 =-0.1452,a 01 =0.8259,a 20 =0.1102,a 11 =0.5709,a 02 =0.1138,a 21 =-0.3019,a 12 =-0.5340,a 22 =0.5203.

[0070] S7, establish the correction parameter equation Y=f(X1, X2, ..., X n ) and stored in a gas analyzer;

[0071] In this embodiment, the correction parameter equation established according to the above fitting coefficient solution is as follows:

[0072] f(X1,X2)

[0073] =0.0401-0.1452X1+0.8259X2+0.1102X1 2 +0.5709X1X2+0.1138X2 2 -0.3019X1 2 X2-0.5340X1X2 2 +0.5203X1 2 X2 2 .

[0074] S8, normalizing the measured concentration values ​​of the n gas components of the mixed gas, substituting the normalized measured concentration values ​​into the correction parameter equation and then performing a denormalization process to obtain the concentration value of the i-th gas component to be corrected in the mixed gas after compensation correction;

[0075] Specifically, the maximum values ​​of the calibration concentration ranges of the first, second, ..., nth gas components of the mixed gas are taken respectively, and the measured concentration values ​​of each gas component are normalized to obtain the normalized measured concentration values ​​of each gas component.

[0076] Will Substitute the correction parameter equation Y = f(X1, X2, ..., X n ),get Take the maximum value of the calibration concentration range of the i-th gas component to be calibrated in the mixed gas, Perform an anti-normalization process to obtain the concentration value of the i-th gas component to be corrected after compensation correction.

[0077] In this embodiment, the first step is to take the maximum value of the calibration concentration range of the high-concentration gas component SO2 as 8000 mg / m 3 , the measured concentration value of SO2, a high concentration gas component in the mixed gas to be detected, is normalized and obtained [8057.4, 8043.7, 8024.1, 8002.7, 1518.9] The maximum value of the calibration concentration range of low concentration gas component NO is 600 mg / m 3 , the measured concentration value of low-concentration gas component NO in the mixed gas to be detected is normalized [504.8, 344.1, 259.6, 175.0, 49.0] to obtain

[0078] The second step is to normalize the concentration values ​​of each gas component Substituting the correction parameter equation into The maximum value of the calibration concentration range of low concentration gas component NO is 600 mg / m 3 Denormalization The concentration values ​​of each gas component in the mixed gas to be detected after compensation and correction are obtained. The results are as follows:

[0079] SO 2、 The measured concentration of NO in the NO mixed gas is 504.8, 344.1, 259.60, 175.0, 49.0 (unit: mg / m 3 ) to perform compensation correction and obtain concentrations of 599.7, 401.2, 299.5, 199.7, and 49.3 (unit: mg / m 3 ), the standard concentrations are 600, 400, 300, 200, 50 (unit: mg / m 3 ), that is, through compensation correction, the concentration errors were reduced from 15.87%, 13.97%, 13.47%, 12.50%, and 2.00% to 0.05%, 0.30%, 0.17%, 0.15%, and 1.40%, respectively.

[0080] It can be seen that by compensating and correcting the measured concentration of the mixed gas in the present invention, the gas components with large concentration measurement deviations in the mixed gas are corrected, thereby improving the accuracy of the detection of the mixed gas concentration.

[0081] like Figure 4 As shown, a mixed gas concentration detection and correction system for a gas analyzer includes a light source, a measuring cell, a spectrometer, a data acquisition module, a data analysis module and a concentration correction module. The light source emits light that passes through the gas in the measuring cell and is received by the spectrometer. The spectrometer converts the collected optical signal into a digital signal and sends it to the data acquisition module. The data acquisition module is connected to the data analysis module and the concentration correction module respectively.

[0082] The data acquisition module is used to collect the measured concentration data of each component of the mixed gas to be detected and the reference concentration data of each component of the reference mixed gas; the data analysis module is used to establish a correction parameter equation based on the reference concentration value of each component of the reference mixed gas and the standard concentration value and pre-store it in the concentration correction module; the concentration correction module is used to process and correct the measured concentration values ​​of each component of the mixed gas to be detected; the process of establishing the correction parameter equation and processing and correcting the measured concentration values ​​of each component of the mixed gas to be detected is operated according to the steps of the gas analyzer mixed gas concentration detection and correction method.

[0083] A non-transitory computer-readable storage medium includes instructions for executing the mixed gas concentration detection and correction method of a gas analyzer as described in any of the above embodiments.

[0084] An electronic device includes a non-transitory computer-readable storage medium; and one or more processors capable of executing the instructions of the non-transitory computer-readable storage medium.

[0085] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0086] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0087] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0088] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0089] The present invention uses specific embodiments to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for detecting and correcting the concentration of mixed gases in a gas analyzer, characterized in that: The following steps are involved: S1. The mixed gas to be detected is passed into the measuring cell, and the gas analyzer obtains the measured concentration values ​​of n gas components, and determines the calibration concentration range of each gas component according to the measured concentration values; S2, respectively select m1, m2, ..., m in the calibration concentration range of the 1st, 2nd, ..., nth gas component of the mixed gas. n standard concentration values, forming m1*m2*····*m n Mixed gases with different concentration combinations; S3, m1*m2*····*m n Mixed gases of various concentration combinations are sequentially introduced into the gas analyzer for ventilation testing to obtain m1*m2*····*m n Group reference concentration value; S4, sequentially measure the mixed gas m1*m2*····*m n The reference concentration values ​​of the group are normalized to obtain the mixed gas m1*m2*····*m n group normalized reference concentration value; S5. For the i-th (1≤i≤n) gas component to be calibrated in the mixed gas, m i The standard concentration values ​​are normalized to obtain the m of the i-th gas component to be corrected. i Normalized standard concentration value; S6, according to m1*m2*····*m n The normalized reference concentration value and m of the i-th gas component to be corrected i Normalized standard concentration values ​​are used to establish a polynomial fitting equation to obtain the fitting coefficient solution; S7, establish the correction parameter equation Y=f(X1, X2,…, X n ) and stored in a gas analyzer; S8. Normalize the measured concentration values ​​of the n gas components of the mixed gas, substitute the normalized measured concentration values ​​into the correction parameter equation and then perform a denormalization process to obtain the concentration value of the i-th gas component to be corrected in the mixed gas after compensation correction.

2. The mixed gas concentration detection and correction method of a gas analyzer as claimed in claim 1, characterized in that: In step S4, the mixed gas m1*m2*····*m n The reference concentration values ​​of the group were normalized as follows: The maximum values ​​of the calibration concentration ranges of the first, second, ..., nth gas components of the mixed gas are taken respectively, and the reference concentration values ​​of the gas components of the mixed gas are normalized.

3. The mixed gas concentration detection and correction method of a gas analyzer as claimed in claim 2, characterized in that: In step S5, the m of the i-th (1≤i≤n) gas component to be calibrated in the mixed gas is i The standard concentration values ​​are normalized as follows: Take the maximum value of the calibration concentration range of the i-th gas component to be calibrated, and then calculate the m i The standard concentration values ​​were normalized.

4. The mixed gas concentration detection and correction method of a gas analyzer as claimed in claim 3, characterized in that: In step S6, the polynomial fitting steps are as follows: m1*m2*····*m n The concentration values ​​of the 1st, 2nd, ..., nth gas components in the group normalized reference concentration value are the independent variables X1, X2, ..., X n , with m of the i-th gas component to be corrected i Normalized standard concentration values ​​are repeated m1*…*m i-1 *m i+1 *…*m n The dependent variable Y is used, and a polynomial fitting equation is established to obtain the fitting coefficient solution.

5. The mixed gas concentration detection and correction method of a gas analyzer as claimed in claim 4, characterized in that: In step S6, the method for obtaining the fitting coefficient solution includes constructing the fitting polynomial into the form of a linear equation system of Ax=b, and solving the linear equation system by the least squares method to obtain the following solution: x=(A′A) -1 A′b。 6. The mixed gas concentration detection and correction method of a gas analyzer as claimed in claim 4, characterized in that: In step S6, the method for obtaining the fitting coefficient solution includes constructing the fitting polynomial into the form of a linear equation system Ax=b, solving the linear equation system using a singular value decomposition method, performing singular value decomposition on A to obtain A=USV′, and obtaining the following solution: x=V(S\(U'b)).

7. The mixed gas concentration detection and calibration method of a gas analyzer according to claim 5 or 6, characterized in that: In step S8, the normalization and denormalization processing steps are as follows: Take the maximum values ​​of the calibration concentration range of the first, second, ..., nth gas components of the mixed gas respectively, normalize the measured concentration values ​​of each gas component, and obtain the normalized measured concentration values ​​of each gas component Will Substitute the correction parameter equation Y = f(X1, X2, ..., X n ),get Take the maximum value of the calibration concentration range of the i-th gas component to be calibrated in the mixed gas, Perform an anti-normalization process to obtain the concentration value of the i-th gas component to be corrected after compensation correction.

8. A mixed gas concentration detection and correction system for a gas analyzer, comprising a light source, a measuring cell, a spectrometer, a data acquisition module and a data analysis module, characterized in that: It also includes a concentration correction module, wherein the light source emits light that passes through the gas in the measuring cell and is received by the spectrometer, and the spectrometer converts the collected optical signal into a digital signal and sends it to the data acquisition module, which is respectively connected to the data analysis module and the concentration correction module; The data acquisition module is used to collect the measured concentration data of each component of the mixed gas to be detected and the reference concentration data of each component of the reference mixed gas; the data analysis module is used to establish a correction parameter equation based on the reference concentration value of each component of the reference mixed gas and the standard concentration value and pre-store it in the concentration correction module; the concentration correction module is used to process and correct the measured concentration values ​​of each component of the mixed gas to be detected; the process of establishing the correction parameter equation and processing and correcting the measured concentration values ​​of each component of the mixed gas to be detected is operated according to the steps of the gas analyzer mixed gas concentration detection and correction method.

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