Rapid and portable detection system and detection method for methanol and ethanol in vehicle gasoline

Abstract

The invention relates to the technical field of gasoline detection, in particular to a rapid and portable detection system and detection method for methanol and ethanol in automotive gasoline. According to the Savitzky-Golay smoothing algorithm, the inherent characteristics (signal-to-noise ratio and complexity) of the spectral data are calculated firstly through the preprocessing module before the collected spectral data are preprocessed, then the polynomial order n of the Savitzky-Golay smoothing algorithm is determined according to the inherent characteristics of the spectral data, and the robustness of the Savitzky-Golay smoothing algorithm for processing the spectral data is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gasoline detection, in particular to a rapid and portable detection system and method for methanol and ethanol in automotive gasoline. Background Art

[0002] With the rapid development of the automotive industry, the demand for automotive gasoline continues to increase. Methanol and ethanol are often added to gasoline to increase its octane rating and reduce costs. However, excessive addition of methanol and ethanol can damage vehicle engines and have adverse environmental impacts. Therefore, rapid and accurate detection of methanol and ethanol content in automotive gasoline is of great significance.

[0003] Currently, the main methods for detecting methanol and ethanol content in automotive gasoline include gas chromatography and liquid chromatography. These methods suffer from complex procedures, long detection times, the need for specialized personnel and large equipment, and are therefore insufficient for rapid on-site detection. Near-infrared spectroscopy, on the other hand, offers advantages such as rapidity, non-destructiveness, and ease of use, making it widely used in chemical analysis. However, existing instruments based on near-infrared spectroscopy are often bulky and expensive, making them unsuitable for rapid on-site detection. Furthermore, these instruments suffer from limitations in robustness and accuracy. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a rapid and portable detection system and method for methanol and ethanol in automotive gasoline, which are used to solve the problems existing in the prior art.

[0005] According to one aspect of the present invention, a rapid and portable detection system for methanol and ethanol in motor gasoline is provided, comprising the following modules:

[0006] Light source module: used to emit near-infrared light with a wavelength range of 700-2500 nanometers;

[0007] Sample pool: used to hold the gasoline sample to be tested;

[0008] Spectrum acquisition module: used for collecting spectral data of the gasoline sample in the sample pool to near-infrared light;

[0009] Preprocessing module: used to perform preprocessing operations on the spectrum data collected by the spectrum collection module; the preprocessing module includes:

[0010] a signal-to-noise ratio calculation unit, configured to calculate the signal-to-noise ratio of the data collected by the spectrum collection module;

[0011] a signal complexity determination unit, configured to determine the complexity of the data collected by the spectrum collection module;

[0012] a smoothing parameter determination unit, configured to determine a smoothing parameter according to the signal-to-noise ratio and complexity of the data collected by the spectrum collection module;

[0013] a preprocessing unit, configured to perform a preprocessing operation on the data collected by the spectrum collection module according to the smoothing parameter;

[0014] Quantitative analysis module, used to perform quantitative analysis on pre-processed spectral data to obtain the content values ​​of methanol and ethanol in gasoline;

[0015] Display module: used to display the test results, including the content values ​​of methanol and ethanol;

[0016] Power module: provides power to the instrument.

[0017] Preferably, the calculation formula of the signal-to-noise ratio SNR is:

[0018]

[0019] Wherein, μ is the average value of the data collected by the spectrum acquisition module, and σ is the standard deviation of the data collected by the spectrum acquisition module.

[0020] Preferably, the complexity is obtained by counting the number of peaks and troughs of the data collected by the spectrum collection module; and then calculating the complexity according to the number of peaks and troughs;

[0021] The calculation formula for complexity is:

[0022]

[0023] Where m is the number of peaks and troughs, and m0 is the reference value of the number of peaks and troughs.

[0024] Preferably, the smoothing parameter is the polynomial order n of the Savitzky-Golay smoothing algorithm; the specific determination formula is:

[0025]

[0026] Where round() is the rounding function, C is the complexity adjustment coefficient, and Complexity is the complexity.

[0027] Preferably, the light source module uses a pulse xenon lamp as a light source.

[0028] Preferably, the light source module further includes:

[0029] Condensing lens: a condensing lens is provided at the output end of the pulse xenon lamp to focus the divergent light emitted by the pulse xenon lamp to the entrance of the sample cell;

[0030] Fiber optic coupling: using optical fiber to connect the light source to the sample cell;

[0031] Aperture: An aperture is set behind the condenser lens. By adjusting the aperture of the aperture, the intensity of light entering the sample cell can be controlled to avoid excessive light signals from causing detector saturation.

[0032] Preferably, the sample cell is made of quartz glass and has a rectangular shape with dimensions of 20 mm×10 mm×5 mm.

[0033] Preferably, the sample pool further comprises the following structure:

[0034] Anti-reflection coating: The inner wall of the sample cell is coated with an anti-reflection coating;

[0035] Optical path design: The optical path design of the sample cell is straight-through. The near-infrared light emitted by the light source module enters the sample cell vertically, passes through the sample, and directly reaches the spectrum acquisition module.

[0036] According to another aspect of the present invention, a method for rapid and portable detection of methanol and ethanol in automotive gasoline is provided. The method uses the aforementioned rapid and portable detection system for methanol and ethanol in automotive gasoline. The method comprises:

[0037] Turn on the power module of the detection system and preheat the detection system for 10 minutes;

[0038] Inject the automotive gasoline sample to be tested into the sample cell;

[0039] Press the detection button, and the light source module emits near-infrared light. After passing through the gasoline sample in the sample pool, the near-infrared light is collected by the spectrum acquisition module.

[0040] The preprocessing module preprocesses the collected spectral data;

[0041] The data preprocessing module preprocesses the collected spectral data specifically as follows:

[0042] The signal-to-noise ratio calculation unit is used to calculate the signal-to-noise ratio of the data collected by the spectrum collection module;

[0043] The signal complexity determination unit is used to determine the complexity of the data collected by the spectrum acquisition module;

[0044] The smoothing parameter determination unit is used to determine the smoothing parameter according to the signal-to-noise ratio and complexity of the data collected by the spectrum collection module;

[0045] The preprocessing unit is used to perform a preprocessing operation on the data collected by the spectrum collection module according to the smoothing parameter;

[0046] The quantitative analysis module is used to perform quantitative analysis on the pre-processed spectral data to obtain the content values ​​of methanol and ethanol in gasoline;

[0047] The display module is used to display the content values ​​of methanol and ethanol;

[0048] After the test is completed, turn off the instrument power switch, clean the sample pool, and end the test.

[0049] The present invention has the following technical effects:

[0050] The present invention uses a preprocessing module to first calculate the inherent characteristics of the spectral data (signal-to-noise ratio and complexity) before preprocessing the collected spectral data. Then, the polynomial order n of the Savitzky-Golay smoothing algorithm is determined based on the inherent characteristics of the spectral data, thereby improving the robustness of the Savitzky-Golay smoothing algorithm in processing spectral data.

[0051] The present invention also uses a pulsed xenon lamp as the light source and efficiently transmits light to the sample cell via fiber coupling. This design not only improves light utilization but also allows for more flexible layout of the light source module, facilitating instrument miniaturization. Furthermore, the optimized design of the collimating lens, focusing lens, and slit ensures efficient transmission and acquisition of optical signals, enabling both miniaturization and portability of the detection system. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0053] Figure 1 The figure is a schematic diagram of a rapid and portable detection system for methanol and ethanol in automotive gasoline provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0054] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are also within the scope of protection of the present invention.

[0055] Example 1, attached Figure 1 The schematic diagram of the rapid portable detection system for methanol and ethanol in motor gasoline is shown in the attached figure. Figure 1 As shown, a rapid and portable detection system for methanol and ethanol in automotive gasoline includes the following modules:

[0056] Light source module: used to emit near-infrared light with a wavelength range of 700-2500 nanometers;

[0057] Sample pool: used to hold the gasoline sample to be tested;

[0058] Spectrum acquisition module: used for collecting spectral data of the gasoline sample in the sample pool to near-infrared light;

[0059] Preprocessing module: used for performing preprocessing operations on the spectrum data collected by the spectrum collection module;

[0060] Quantitative analysis module, used to perform quantitative analysis on pre-processed spectral data to obtain the content values ​​of methanol and ethanol in gasoline;

[0061] Display module: used to display the test results, including the content values ​​of methanol and ethanol;

[0062] Power module: provides power to the instrument.

[0063] In this embodiment, the light source module is one of the core components of a portable instrument for rapid detection of methanol and ethanol in automotive gasoline based on near-infrared spectroscopy. Its primary function is to provide stable, high-intensity near-infrared light to ensure that the spectrum acquisition module can acquire high-quality spectral data. The design of the light source module must meet the following requirements:

[0064] Wavelength range: It can cover the near-infrared band of 700-2500 nanometers, which is the main distribution area of ​​the characteristic absorption peaks of methanol and ethanol.

[0065] Light intensity stability: The light intensity fluctuation of the light source must be controlled within a very small range to ensure the repeatability and reliability of the spectral data.

[0066] Pulse characteristics: Using a pulsed light source can improve the signal-to-noise ratio of spectral acquisition while reducing the power consumption of the light source.

[0067] Miniaturization and portability: The light source module needs to match the portability design of the entire instrument, with a small size and light weight.

[0068] In this embodiment, the light source module uses a pulsed xenon lamp as a light source. The pulsed xenon lamp has the following advantages: wide spectral range: the pulsed xenon lamp can emit light in a wide spectral range from ultraviolet to near infrared, completely covering the near-infrared band of 700-2500 nanometers, and is suitable for the detection of a variety of organic matter; high brightness: in pulse mode, the xenon lamp can provide high-brightness light output, ensuring that sufficient light intensity reaches the sample cell, and a clear spectral signal can be obtained even in a short integration time; good stability: the pulsed xenon lamp has small light intensity fluctuations and high stability, and can provide a stable spectral baseline; low power consumption: in pulse mode, the average power consumption of the xenon lamp is low, which is suitable for the power requirements of portable instruments.

[0069] The pulse parameters of the pulsed xenon lamp have a significant impact on the efficiency and quality of spectral acquisition. Furthermore, this embodiment further defines the pulse parameters of the light source module:

[0070] The parameters of the pulse xenon lamp are designed as follows:

[0071] Pulse frequency: 10-100 Hz. The selection of pulse frequency requires a balance between the speed of spectrum acquisition and the thermal stability of the light source. A higher pulse frequency can increase the speed of spectrum acquisition but may cause the light source to overheat. This invention selects a pulse frequency of 10-100 Hz to ensure fast acquisition while preventing light source overheating.

[0072] Pulse width: 1-10 microseconds. The pulse width determines the energy output of each pulse. A narrower pulse width can improve the signal-to-noise ratio of the spectrum while reducing heat accumulation in the light source. In this embodiment, a pulse width of 1-10 microseconds is selected to minimize thermal effects while maintaining light intensity.

[0073] Furthermore, in order to ensure that the light from the light source module can efficiently enter the sample cell and be received by the spectrum acquisition module, the light source module also includes the following optical design:

[0074] Condensing lens: A condensing lens is provided at the output end of the pulse xenon lamp to focus the divergent light emitted by the pulse xenon lamp to the entrance of the sample cell, thereby improving the utilization rate of light;

[0075] Fiber optic coupling: The light source is connected to the sample cell using an optical fiber. Fiber optic coupling not only improves the light transmission efficiency, but also makes the layout between the light source module and the sample cell more flexible.

[0076] Aperture: An aperture is set behind the condenser lens. By adjusting the aperture of the aperture, the intensity of light entering the sample cell can be controlled to avoid excessive light signals from causing detector saturation.

[0077] In this embodiment, a pulsed xenon lamp is used as the light source, and light is efficiently transmitted to the sample cell via fiber coupling. This design not only improves light utilization, but also makes the layout of the light source module more flexible, facilitating the miniaturization of the instrument.

[0078] The main function of the sample pool is to hold the automotive gasoline sample to be tested and ensure that the near-infrared light can effectively pass through the sample so that the spectrum acquisition module can obtain high-quality absorption spectrum data.

[0079] In this embodiment, quartz glass has extremely high light transmittance in the near-infrared band (700-2500 nanometers), which can ensure the efficient passage of near-infrared light. It also has excellent chemical stability and can withstand chemical corrosion from gasoline and its additives, ensuring the service life of the sample cell. Therefore, the sample cell uses quartz glass as the main material;

[0080] The sample cell is a rectangular parallelepiped, measuring 20mm x 10mm x 5mm (length x width x height). This design ensures a sufficient optical path length (5mm) while facilitating sample injection and cleaning. A sealed injection port is located at the top of the sample cell, fitted with a silicone gasket and a screw-on cap for easy sample injection and sealing. A drain port is located at the bottom of the sample cell for easy removal of waste liquid after cleaning, making it easier to use and maintain.

[0081] At the same time, in order to improve the efficiency and quality of spectrum acquisition, the sample pool also includes the following structures:

[0082] Anti-reflection coating: The inner wall of the sample cell is coated with an anti-reflection coating, which can reduce the reflection loss of light on the inner wall of the sample cell and improve the transmittance of light. The material of the anti-reflection coating is silicon dioxide ( ) to ensure the best anti-reflection effect;

[0083] Optical path design: The optical path design of the sample cell is straight-through. The near-infrared light emitted by the light source module enters the sample cell vertically, passes through the sample and directly reaches the spectrum acquisition module. This design can minimize light scattering and absorption and improve the quality of the spectral signal.

[0084] The spectrum acquisition module includes a grating spectrometer system, a photodetector, an optical system, and a signal acquisition unit. The grating spectrometer system is the core of the spectrum acquisition module and is used to decompose composite light into monochromatic light of different wavelengths. In this embodiment, a holographic grating is used as the spectrometer element. The holographic grating has high diffraction efficiency and high resolution, and can accurately distinguish characteristic absorption peaks in the near-infrared spectrum. Furthermore, in this embodiment, the line density of the holographic grating is 1200-2400 lines / mm, which can meet the spectrometry requirements of the 700-2500 nanometer band. At the same time, the holographic grating is small in size, which is suitable for the compact design of portable instruments. The photodetector is used to convert the split optical signal into an electrical signal. In this embodiment, an indium gallium arsenide (InGaAs) detector is used.

[0085] In order to ensure that the optical signal can efficiently pass from the light source through the sample cell to the detector, the spectrum acquisition module further includes an optical system, which specifically includes:

[0086] Collimating lens: A collimating lens is set at the outlet of the sample cell to collimate the divergent light after passing through the sample cell into parallel light, thereby improving the light transmission efficiency;

[0087] Focusing lens: A focusing lens is set in front of the photodetector to focus the split monochromatic light onto the photosensitive surface of the detector to further increase the intensity of the light signal;

[0088] Slit: A slit is set in front of the holographic grating. By adjusting the width of the slit, the intensity of light entering the spectroscopic system can be controlled, and the resolution of the spectrum can be improved.

[0089] The spectrum acquisition module also includes a signal acquisition unit, which is used to convert the analog signal output by the detector into a digital signal and perform preliminary processing. In this embodiment, the signal acquisition unit specifically includes:

[0090] Analog-to-digital converter (ADC): A high-precision analog-to-digital converter is used to convert the analog signal output by the photodetector into a digital signal to ensure high fidelity of the signal;

[0091] Data synchronization unit: ensures precise synchronization between the pulse emission of the light source, the spectroscopic action of the grating and the signal acquisition of the photodetector through the synchronization trigger signal, thus avoiding errors in data acquisition.

[0092] In this embodiment, a combination of a holographic grating and an InGaAs detector is used to achieve high-resolution and high-sensitivity spectral acquisition, which can accurately detect the characteristic absorption peaks of methanol and ethanol; at the same time, through the optimized design of the collimating lens, focusing lens and slit, the efficient transmission and acquisition of the optical signal is ensured, and the miniaturization and portability of the detection system are achieved.

[0093] The preprocessing module is the core component of the rapid and portable detection system for methanol and ethanol in automotive gasoline. Its main function is to preprocess the collected spectral data. At the same time, the preprocessing module is also the most time-consuming step in the methanol and ethanol detection process. In existing designs, the spectral acquisition module is generally directly input into the built-in spectral pre-data processing program, which will result in a long data processing link. At the same time, the data preprocessing is not robust. Therefore, to overcome the above problems, this embodiment improves the preprocessing module of the existing technology to achieve the purpose of rapid detection and improve the robustness of data preprocessing.

[0094] Specifically, the preprocessing module includes:

[0095] a signal-to-noise ratio calculation unit, configured to calculate the signal-to-noise ratio of the data collected by the spectrum collection module;

[0096] The calculation formula of the signal-to-noise ratio SNR is:

[0097]

[0098] Wherein, μ is the average value of the data collected by the spectrum acquisition module, and σ is the standard deviation of the data collected by the spectrum acquisition module;

[0099] a signal complexity determination unit, configured to determine the complexity of the data collected by the spectrum collection module;

[0100] Wherein, the complexity is obtained by counting the number of peaks and troughs of the data collected by the spectrum collection module; and then calculating the complexity according to the number of peaks and troughs;

[0101] The calculation formula for complexity is:

[0102]

[0103] Where m is the number of peaks and troughs, and m0 is the reference value of the number of peaks and troughs;

[0104] a smoothing parameter determination unit, configured to determine a smoothing parameter according to the signal-to-noise ratio and complexity of the data collected by the spectrum collection module;

[0105] The smoothing parameter is the polynomial order n of the Savitzky-Golay smoothing algorithm; the specific determination formula is:

[0106]

[0107] Where round() is the rounding function and C is the complexity adjustment coefficient;

[0108] A preprocessing unit is used to perform a preprocessing operation on the data collected by the spectrum collection module according to the smoothing parameter.

[0109] The preprocessing module provided in this embodiment first calculates the inherent characteristics of the spectral data (signal-to-noise ratio and complexity) before preprocessing the collected spectral data. Then, the polynomial order n of the Savitzky-Golay smoothing algorithm is determined based on the inherent characteristics of the spectral data, thereby improving the robustness of the Savitzky-Golay smoothing algorithm in processing spectral data.

[0110] In the rapid and portable detection system for methanol and ethanol in automotive gasoline, the quantitative analysis module is a key part for realizing the prediction of methanol and ethanol content from spectral data. In this embodiment, methanol and ethanol are detected through a convolutional neural network model. The input of the convolutional neural network model is the data collected by the preprocessed spectral acquisition module, and the output of the convolutional neural network model is the methanol and ethanol content.

[0111] In Example 2, the present invention further provides a method for rapid and portable detection of methanol and ethanol in automotive gasoline. The method uses a rapid and portable detection system for methanol and ethanol in automotive gasoline according to Example 1. The method comprises:

[0112] Turn on the power module of the detection system and preheat the detection system for 10 minutes;

[0113] Inject the automotive gasoline sample to be tested into the sample cell;

[0114] Press the detection button, and the light source module emits near-infrared light. After passing through the gasoline sample in the sample pool, the near-infrared light is collected by the spectrum acquisition module.

[0115] The preprocessing module preprocesses the collected spectral data;

[0116] The data preprocessing module preprocesses the collected spectral data specifically as follows:

[0117] The signal-to-noise ratio calculation unit is used to calculate the signal-to-noise ratio of the data collected by the spectrum collection module;

[0118] The signal complexity determination unit is used to determine the complexity of the data collected by the spectrum acquisition module;

[0119] The smoothing parameter determination unit is used to determine the smoothing parameter according to the signal-to-noise ratio and complexity of the data collected by the spectrum collection module;

[0120] The preprocessing unit is used to perform a preprocessing operation on the data collected by the spectrum collection module according to the smoothing parameter.

[0121] The quantitative analysis module is used to perform quantitative analysis on the pre-processed spectral data to obtain the content values ​​of methanol and ethanol in gasoline;

[0122] The display module is used to display the content values ​​of methanol and ethanol.

[0123] After the test is completed, turn off the instrument power switch, clean the sample pool, and end the test.

[0124] Example 3: The present invention also provides an electronic device, including one or more processors and a memory.

[0125] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0126] The memory may include one or more computer program products, and the computer program product may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor may execute the program instructions to implement a rapid and portable detection method for methanol and ethanol in automotive gasoline of any embodiment of the present application described above and / or other desired functions. Various contents such as initial external parameters, threshold values, etc. may also be stored in the computer-readable storage medium.

[0127] In one example, the electronic device may further include an input device and an output device, wherein these components are interconnected via a bus device and / or other connection mechanisms (not shown). The input device may include, for example, a keyboard, a mouse, etc. The output device may output various information to the outside, including warning information, braking force, etc. The output device may include, for example, a display, a speaker, a printer, a communication network, and remote output devices connected thereto.

[0128] Of course, for the sake of simplicity, components such as buses, input / output interfaces, etc. are omitted. In addition, the electronic device may further include any other appropriate components according to specific application scenarios.

[0129] In addition to the above-mentioned methods and devices, an embodiment of the present application may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to implement the functions of a rapid and portable method for detecting methanol and ethanol in automotive gasoline provided in any embodiment of the present application.

[0130] The computer program product may be written in any combination of one or more programming languages ​​to implement the program code for performing the operations of the embodiments of the present application, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0131] In addition, an embodiment of the present application may also be a computer-readable storage medium having computer program instructions stored thereon. When the computer program instructions are executed by a processor, the processor implements a rapid and portable method for detecting methanol and ethanol in automotive gasoline provided in any embodiment of the present application.

[0132] The computer-readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can, for example, include but is not limited to an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor device, device or component, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0133] It should be noted that the terms used in the present invention are only for describing specific embodiments and are not intended to limit the scope of this application. As shown in the present specification, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular and may also include the plural. The terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method or device comprising a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of further restrictions, the elements defined by the sentence "comprise a..." do not exclude the presence of other identical elements in the process, method or device comprising the elements.

[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A rapid and portable detection system for methanol and ethanol in automotive gasoline, characterized in that: include: Light source module: used to emit near-infrared light with a wavelength range of 700-2500 nanometers; Sample pool: used to hold the gasoline sample to be tested; Spectrum acquisition module: used for collecting spectral data of the gasoline sample in the sample pool to near-infrared light; Preprocessing module: used for performing preprocessing operations on the spectrum data collected by the spectrum collection module; The pre-processing module comprises: a signal-to-noise ratio calculation unit, configured to calculate the signal-to-noise ratio of the data collected by the spectrum collection module; a signal complexity determination unit, configured to determine the complexity of the data collected by the spectrum collection module; a smoothing parameter determination unit, configured to determine a smoothing parameter according to the signal-to-noise ratio and complexity of the data collected by the spectrum collection module; a preprocessing unit, configured to perform a preprocessing operation on the data collected by the spectrum collection module according to the smoothing parameter; Quantitative analysis module, used to perform quantitative analysis on pre-processed spectral data to obtain the content values ​​of methanol and ethanol in gasoline; Display module: used to display the test results, including the content values ​​of methanol and ethanol; Power module: provides power to the instrument.

2. The rapid and portable detection system for methanol and ethanol in automotive gasoline according to claim 1, characterized in that: The calculation formula of the signal-to-noise ratio SNR is: Wherein, μ is the average value of the data collected by the spectrum acquisition module, and σ is the standard deviation of the data collected by the spectrum acquisition module.

3. The rapid and portable detection system for methanol and ethanol in automotive gasoline according to claim 1 or 2, characterized in that: The complexity is obtained by counting the number of peaks and valleys of the data collected by the spectrum acquisition module; and then calculating the complexity based on the number of peaks and valleys; The calculation formula for complexity is: Where m is the number of peaks and troughs, and m0 is the reference value of the number of peaks and troughs.

4. The rapid and portable detection system for methanol and ethanol in automotive gasoline according to claim 1, characterized in that: The smoothing parameter is the polynomial order n of the Savitzky-Golay smoothing algorithm; the specific determination formula is: Where round() is the rounding function, C is the complexity adjustment coefficient, and Complexity is the complexity.

5. The rapid and portable detection system for methanol and ethanol in automotive gasoline according to claim 1, characterized in that: The light source module uses a pulse xenon lamp as a light source.

6. The rapid and portable detection system for methanol and ethanol in automotive gasoline according to claim 5, characterized in that: The light source module further includes: Condensing lens: a condensing lens is provided at the output end of the pulse xenon lamp to focus the divergent light emitted by the pulse xenon lamp to the entrance of the sample cell; Fiber optic coupling: using optical fiber to connect the light source to the sample cell; Aperture: An aperture is set behind the condenser lens. By adjusting the aperture of the aperture, the intensity of light entering the sample cell can be controlled to avoid excessive light signals from causing detector saturation.

7. The rapid and portable detection system for methanol and ethanol in automotive gasoline according to claim 1, characterized in that: The sample cell is made of quartz glass and has a rectangular shape with dimensions of 20 mm×10 mm×5 mm.

8. The rapid and portable detection system for methanol and ethanol in automotive gasoline according to claim 7, characterized in that: The sample pool also includes the following structure: Anti-reflection coating: The inner wall of the sample cell is coated with an anti-reflection coating; Optical path design: The optical path design of the sample cell is straight-through. The near-infrared light emitted by the light source module enters the sample cell vertically, passes through the sample, and directly reaches the spectrum acquisition module.

9. A rapid and portable method for detecting methanol and ethanol in motor gasoline, characterized in that: The method uses a rapid portable detection system for methanol and ethanol in automotive gasoline according to any one of claims 1 to 8, and the method comprises: Turn on the power module of the detection system and preheat the detection system for 10 minutes; Inject the automotive gasoline sample to be tested into the sample cell; Press the detection button, and the light source module emits near-infrared light. After passing through the gasoline sample in the sample pool, the near-infrared light is collected by the spectrum acquisition module. The preprocessing module preprocesses the collected spectral data; The data preprocessing module preprocesses the collected spectral data specifically as follows: The signal-to-noise ratio calculation unit is used to calculate the signal-to-noise ratio of the data collected by the spectrum collection module; The signal complexity determination unit is used to determine the complexity of the data collected by the spectrum acquisition module; The smoothing parameter determination unit is used to determine the smoothing parameter according to the signal-to-noise ratio and complexity of the data collected by the spectrum collection module; The preprocessing unit is used to perform a preprocessing operation on the data collected by the spectrum collection module according to the smoothing parameter; The quantitative analysis module is used to perform quantitative analysis on the pre-processed spectral data to obtain the content values ​​of methanol and ethanol in gasoline; The display module is used to display the content values ​​of methanol and ethanol; After the test is completed, turn off the instrument power switch, clean the sample pool, and end the test.

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