A laser domestic combustible gas detector

Abstract

The application relates to the technical field of combustible gas detection, and discloses a laser household combustible gas detector which comprises a detection assembly, a heating assembly, a temperature measurement assembly, a control assembly and a heat dissipation assembly. When the core temperature is less than a heat dissipation threshold value, the heating assembly continuously works; when the core temperature change gradient is greater than a high-temperature alarm threshold value, real-time operation state data of the detector is acquired, Kalman filtering and normalization processing are performed on the real-time operation state data, an isolated forest model is run, the abnormal real-time operation state data is marked, and an abnormal state vector is constructed according to the abnormal real-time operation state data; the abnormal state vector is input into a fault diagnosis model, and a fault type probability is output. The technical scheme only controls the core temperature of the sensor by cooperation of the heating assembly and a heat dissipation fan, and is low in cost and small in power consumption. Meanwhile, dynamic adjustment of a detection result is realized by cooperation of a temperature compensation algorithm, and the methane detection precision is improved.

Description

Technical Field

[0001] This invention relates to the field of combustible gas detection technology, specifically to a laser-based household combustible gas detector. Background Technology

[0002] Most household combustible gas detectors use semiconductor-type gas sensors as their core sensor element. These sensors commonly suffer from problems such as susceptibility to interference, false alarms, and inaccurate readings. To address these issues, some detectors are gradually adopting laser-type methane sensors for gas concentration detection. These sensors offer advantages such as strong anti-interference capabilities and accurate readings, resulting in more stable and reliable detector performance.

[0003] However, laser-based methane sensors have certain temperature requirements for operation; the core sensor components can only achieve high accuracy at specific operating temperatures. As the temperature rises or falls, the wavelength of the laser emitted by the laser shifts, causing it to deviate from the absorption peak wavelength of methane, thus affecting the sensor's measurement accuracy.

[0004] Some existing technologies employ TEC (Transient Temperature Coefficient) bidirectional temperature control to regulate the sensor's operating temperature. Internally, a semiconductor cooler based on the Peltier effect achieves bidirectional heating or cooling, thereby controlling the operating temperature of the sensor's core components. However, laser sensors using TEC bidirectional temperature control technology are relatively expensive and cannot currently be applied to ordinary household scenarios.

[0005] For laser sensors without TEC bidirectional temperature control, existing technologies mostly rely on passive heat dissipation to control the internal temperature, or rely solely on heating resistors to achieve unidirectional heating to maintain a constant temperature. However, when the ambient temperature is high (e.g., >60℃), the heat dissipation efficiency will drop sharply, causing the internal temperature of the sensor to exceed the limit, resulting in decreased accuracy or even complete failure. Summary of the Invention

[0006] To address the technical problem that existing technologies cannot control the core temperature of laser detectors at low cost, this application provides a laser household combustible gas detector, comprising: a detection component, a heating component, a temperature measurement component, a control component, and a heat dissipation component;

[0007] The detection component is used to emit and receive laser signals, and to measure the intensity of the received laser signals;

[0008] The heating assembly is used to heat the inside of the detector in order to adjust the core temperature of the detector;

[0009] The temperature measurement component includes an external temperature sensor and an internal temperature sensor. The external temperature sensor is used to measure the ambient temperature, and the internal temperature sensor is used to measure the core temperature of the detector.

[0010] The heat dissipation component includes a cooling fan, which is used to reduce the core temperature of the detector.

[0011] The control component is used to calculate the original concentration value of combustible gas based on the intensity of the laser signal, and to correct the original concentration value based on the core temperature and ambient temperature to obtain the true concentration value.

[0012] The control component is also used to change the operating mode of the cooling fan and the heating component according to the core temperature and / or ambient temperature. When the core temperature is less than the heat dissipation threshold, the heating component works continuously. When the core temperature is greater than the heat dissipation threshold, the heating cycle and heating duty cycle are calculated according to the core temperature and the ideal operating temperature. During the heating cycle, the heating component and the cooling component work intermittently and alternately.

[0013] Specifically, the control method of the control component includes the following steps:

[0014] The system periodically acquires real-time ambient temperature, real-time core temperature of the detector, and raw concentration values ​​of combustible gases in the environment.

[0015] The original concentration value is corrected based on the real-time core temperature and the real-time ambient temperature to obtain the corrected concentration value of combustible gas in the environment;

[0016] If the real-time core temperature is less than the heat dissipation threshold, the detector is continuously heated. If not, the heating cycle and heating duty cycle are calculated based on the real-time core temperature and the ideal operating temperature. During the heating cycle, the detector is alternately heated and cooled according to the heating duty cycle.

[0017] The technical effects and advantages of this invention are as follows: By monitoring the ambient temperature and the core temperature of the detector in real time, the working mode of the heating component is controlled. Simultaneously, the working duration of the heat dissipation component is controlled based on the ambient and core temperatures, achieving dynamic adjustment of the working modes of the heating and heat dissipation components. This technical solution achieves control of the sensor core temperature solely through the cooperation of the heating component and the cooling fan, resulting in low cost and low power consumption. Furthermore, the temperature compensation algorithm enables dynamic adjustment of the detection results, improving the accuracy of methane detection. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the detector of the present invention.

[0019] Figure 2This is a schematic diagram of the heat dissipation component of the present invention.

[0020] Figure 3 This is a general flowchart of the control method for the control component of the present invention.

[0021] Figure 4 This is a schematic diagram of the standard deviation surface in the control method of the control component of the present invention.

[0022] Figure 5 This is a flowchart illustrating fault diagnosis in the control method of the present invention.

[0023] The attached figures are labeled as follows: 1. Detection component; 2. Heating component; 3. Temperature measurement component; 31. External temperature sensor; 32. Internal temperature sensor; 4. Control component; 5. Heat dissipation component; 51. Cooling fan; 52. Heat dissipation substrate; 53. Wavy heat dissipation fins. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Experiments show that temperature affects the accuracy of combustible gas detectors not only by influencing the wavelength of the laser emitted by its laser, but also by affecting the peak wavelength of light absorbed by the combustible gas (methane is a common combustible gas, and will be used hereafter to represent combustible gases for brevity, but this is not a limitation of the invention). At different ambient temperatures, the thermal motion of methane molecules varies, causing changes in the peak wavelength of its absorption. Therefore, when performing temperature compensation on the detection results of combustible gas detectors, it is necessary to consider not only the laser wavelength drift caused by changes in the laser emitter's own temperature, but also the influence of ambient temperature on the peak wavelength of absorption by combustible gases such as methane.

[0026] In some application scenarios, such as outdoor use in summer, the intense sunlight can cause the internal temperature of the detector to rise continuously, leading to signal drift in the internal laser or photosensitive element. Without effective heat dissipation measures, the internal temperature of the detector can become excessively high, even exceeding the allowable operating temperature of various electronic components, resulting in overheating damage.

[0027] Based on the above analysis, and referring to Figure 1In order to reduce the impact of temperature changes on the accuracy of methane detection, the present invention provides a laser household combustible gas detector, including: a detection component 1, a heating component 2, a temperature measurement component 3, a control component 4, and a heat dissipation component 5.

[0028] The detection component 1 is used to emit and receive laser signals, and to measure the intensity of the received laser signals;

[0029] Heating component 2 is used to heat the inside of the detector in order to adjust the core temperature of the detector;

[0030] Temperature measurement component 3 includes an external temperature sensor 31 and an internal temperature sensor 32. The external temperature sensor 31 is used to measure the ambient temperature, and the internal temperature sensor 32 is used to measure the core temperature of the detector.

[0031] The heat dissipation component 5 includes a cooling fan 51, which is used to reduce the core temperature of the detector.

[0032] The control component 4 is used to calculate the original concentration value of combustible gas based on the intensity of the laser signal, and to correct the original concentration value based on the core temperature and ambient temperature to obtain the true concentration value.

[0033] The control component 4 is also used to change the working mode of the cooling fan 51 and the heating component 2 according to the core temperature and / or ambient temperature. When the core temperature is less than the heat dissipation threshold, the heating component 2 works continuously. When the core temperature is greater than the heat dissipation threshold, the heating cycle and heating duty cycle are calculated according to the core temperature and the ideal working temperature. During the heating cycle, the heating component 2 and the cooling component 5 work intermittently and alternately.

[0034] Specifically, the cooling fan 51 can be an axial fan or a miniature turbine fan commonly used in computer cooling systems.

[0035] Specifically, in order to improve the thermal conductivity of the detector housing and increase the heat dissipation efficiency of the cooling fan 51, the heat dissipation assembly 5 also includes a heat dissipation substrate 52 and corrugated heat dissipation fins 53, as shown in the reference. Figure 2 A heat dissipation substrate 52 is disposed on the detector's outer shell. The heat dissipation substrate 52 adopts a copper-aluminum composite structure, with a copper layer thickness of 0.8 mm to quickly dissipate high temperatures from the detector, and an aluminum layer thickness of 1.2 mm to maintain good thermal conductivity while reducing weight. Wavy heat dissipation fins 53 are disposed on the heat dissipation substrate 52, preferably with a height of 15 mm, a spacing of 1.5 mm, and an inclination angle of 30°. Their wavy shape increases airflow turbulence and increases the heat dissipation area by 210%. The surface of the wavy heat dissipation fins 53 is also coated with a heat dissipation coating. The emissivity of the heat dissipation coating is greater than 0.8, improving the infrared radiation efficiency in the high-temperature region by 40%.

[0036] By monitoring the ambient temperature and the core temperature of the detector in real time, the operating mode of the heating component 2 is controlled. Simultaneously, the operating time of the heat dissipation component 5 is controlled based on the ambient and core temperatures, achieving dynamic adjustment of the operating modes of the heating component 2 and the heat dissipation component 5. This technical solution achieves control of the sensor core temperature solely through the cooperation of the heating component 2 and the cooling fan 51, resulting in low cost and low power consumption. Furthermore, a temperature compensation algorithm is used to dynamically adjust the detection results, improving the accuracy of methane detection.

[0037] To achieve automatic adjustment of the detector's core temperature and correction of measurement results based on the core temperature and ambient temperature, the detector's control components employ a novel control method, referencing... Figure 3 This includes the following steps:

[0038] S1. Periodically acquire the detector's real-time core temperature, real-time ambient temperature, and the original concentration value of combustible gases in the environment.

[0039] S2. Correct the original concentration value based on the real-time core temperature and the real-time ambient temperature to obtain the corrected concentration value of combustible gas in the environment.

[0040] S3. Determine whether the real-time core temperature is less than the heat dissipation threshold. If yes, control the heating component 2 to work in continuous heating mode to continuously heat the inside of the detector. If no, calculate the heating cycle and heating duty cycle based on the real-time core temperature and the ideal working temperature, and alternately heat and dissipate heat to the inside of the detector according to the heating duty cycle within the heating cycle.

[0041] Because the heat dissipation and heating processes have a certain time delay, this will cause some fluctuation in the laser's temperature (i.e., core temperature). At the same time, the ambient temperature is also constantly changing. Therefore, when improving detection accuracy, it is necessary to correct the detection results based on the ambient temperature and the core temperature.

[0042] Specifically, as a preferred implementation, the temperature compensation C_true can be calculated according to the following formula:

[0043] C_true = C_raw * [1 + β1 * (T_core - 50) +β2 * (T_env - 25)]

[0044] In the formula: β1 is the core temperature drift coefficient, β1=-0.015 / ℃, β2 is the environmental interference coefficient: β2=0.008 / ℃, C_raw is the original measurement value, T_core is the core temperature, and T_env is the ambient temperature.

[0045] For example, during a high and low temperature experiment, 5% methane gas was introduced into the chamber, resulting in an actual methane concentration of 4.855%. The chamber was set to an internal ambient temperature of T_env = 30℃. When the core temperature of the detector was controlled at 55℃ via control component 4, the detector measured an initial concentration value of C_raw = 5% LEL. After calculation using the above formula, the initial concentration value was corrected to 4.825% LEL, with an error of 0.03% compared to the actual methane concentration inside the chamber.

[0046] By using the temperature compensation method described above, the drift of the emitted laser wavelength caused by the temperature change of the laser itself can be taken into account, as well as the influence of the thermal motion change of methane molecules on the absorption peak wavelength. This makes the compensation result closer to the actual measurement value and improves the detection accuracy of the detector.

[0047] Considering that the effect of temperature change on the wavelength of the laser and the peak wavelength of methane absorption is linear only within a certain range, when the temperature change exceeds a certain range, the deviation of methane concentration caused by the temperature change does not strictly follow a linear relationship. Therefore, the accuracy of the compensation result obtained by the above temperature compensation method cannot meet the requirements of higher precision detection.

[0048] The technical solution of the present invention further improves upon the above-mentioned temperature compensation method, including the following steps:

[0049] S21. In the standard high and low temperature experiment, change the methane concentration in the experimental environment and obtain the standard deviation of the corrected concentration value and the true concentration value at different core temperatures and ambient temperatures.

[0050] S22. Using the core temperature as the first coordinate, the ambient temperature as the second coordinate, and the deviation between the corrected concentration value and the true concentration value as the third coordinate, the standard deviation surface is established using a cubic spline interpolation algorithm.

[0051] S23. Repeat steps S21 and S22 to obtain multiple standard deviation surfaces corresponding to different methane concentrations, and form a standard deviation surface array according to the size of the methane concentration values.

[0052] S23. During routine use of the detector, obtain the real-time ambient temperature of the operating environment and the real-time core temperature of the detector.

[0053] S24. When the real-time core temperature is greater than the heat dissipation threshold, the standard deviation surface array is interpolated with the real-time core temperature as the first coordinate and the real-time ambient temperature as the second coordinate to obtain the standard deviation corresponding to multiple different methane concentrations. The multiple standard deviations are interpolated based on the corrected concentration value, and the corrected concentration value is corrected a second time.

[0054] Specifically, during the detector development process, high and low temperature experiments are required to verify the performance of the designed detector under different temperatures. In this experiment, a known concentration of methane is typically introduced into a high and low temperature test chamber (or a dedicated test chamber for toroidal methane detection). By changing the temperature within the test chamber, the detector's measured concentration values ​​at different temperatures are obtained to verify its detection accuracy. In the high and low temperature experiments, measured concentration values ​​at different core and ambient temperatures, as well as the deviations between the measured and actual concentration values, can be collected. Based on this data, a standard deviation surface can be constructed. For example, a standard deviation coordinate system can be established with the core temperature as the x-axis, the ambient temperature as the y-axis, and the deviation between the measured and actual concentration values ​​as the z-axis. By fitting different deviations to the surface, the standard deviation surface is obtained, as shown below. Figure 4 As shown in the diagram. High and low temperature experiments typically involve testing with different concentrations of methane gas to verify the accuracy of the detector's detection results for different concentrations of methane and to comprehensively evaluate the detector's performance. Therefore, after the high and low temperature experiments, a set of standard deviation surface arrays corresponding to different methane concentrations can be obtained. Based on this standard deviation surface array, the detection results during routine operation of the detector can be further corrected.

[0055] During the detector's daily operation, the real-time core temperature measured by the temperature measurement component and the real-time ambient temperature of the operating environment are located in the standard deviation coordinate system. This allows us to obtain the deviation between the current real-time core temperature and the real-time ambient temperature, thereby determining whether the correction concentration value is accurate and performing a secondary correction on the correction concentration value.

[0056] When the core temperature is within a certain range (i.e., the operating temperature range specified by the product, which is generally limited to -20℃ to 80℃ for household models), the above temperature compensation method can achieve high-precision temperature difference correction, and the measurement accuracy after secondary correction can reach ±0.01% LEL.

[0057] However, without proper heat dissipation measures, the accuracy of the temperature compensation method cannot be effectively guaranteed once the core temperature of the detector exceeds a certain value above the ideal operating temperature.

[0058] Therefore, the method provided by the present invention also controls the operation of the heating component 2 and the heat dissipation component 5 through the following steps to control the core temperature:

[0059] S31. When the real-time core temperature is greater than or equal to the heat dissipation threshold (generally taken as 60℃), the heating cycle T_cycle is calculated as follows:

[0060] T_cycle = k1 * (T_core – T_set)

[0061] In the formula, k1 is the temperature control coefficient, which is usually taken as k1=2, and T_set is the ideal working temperature.

[0062] Calculate the heating duty cycle using the following formula:

[0063] Duty = k2 / (T_core + k3)

[0064] In the formula: k2 and k3 are calibration coefficients, generally k2 = 60 and k3 = 25.

[0065] During the heating cycle, the working time of heating component 2 is the heating cycle multiplied by the heating duty cycle, and the remaining time during the heating cycle is forcibly cooled by heat dissipation component 5.

[0066] S32. Determine whether the real-time core temperature is greater than the ideal operating temperature. If so, the heat dissipation component 5 will work first, and the working time will be the remaining time in the heating cycle to reduce the core temperature inside the detector. If not, the heating component 2 will work first, and the working time of the heating component 2 will be the heating cycle multiplied by the heating duty cycle to increase the core temperature inside the detector.

[0067] In the above temperature regulation process, the calculation of the heating cycle and heating duty cycle did not take into account the influence of ambient temperature on heat dissipation efficiency. However, according to the laws of thermodynamics, the heat transfer process is related to the temperature of both objects involved in the heat exchange; therefore, the heat dissipation effect of heat dissipation component 5 should be related to the ambient temperature.

[0068] Based on the above analysis, the control method of the control component also includes the following steps:

[0069] S33. When the heat dissipation component 5 is working, calculate the core temperature change gradient based on the real-time core temperature collected multiple times.

[0070] S34. Determine whether the heat dissipation component 5 will reduce the core temperature below the heat dissipation threshold within the working time determined in step S31. If yes, the heat dissipation component 5 and the heating component 2 will work according to the heating cycle and heating duty cycle. If no, the working time of the heat dissipation component 5 will be recalculated according to the core temperature change gradient.

[0071] Specifically, the following steps are used to determine whether the real-time core temperature can be reduced below the heat dissipation threshold:

[0072] The real-time core temperature is subtracted from the heat dissipation threshold, and the difference between the two is divided by the core temperature change gradient to obtain the cooling time. If the cooling time is less than the working time of the heat dissipation component 5 calculated in step S31, the heat dissipation component 5 performs heat dissipation work according to the working time calculated in step S31. If the cooling time is greater than the working time of the heat dissipation component 5 calculated in step S31, the heat dissipation component 5 works according to the cooling time.

[0073] At the same time, it should also be considered that the heat dissipation component 5 may not be able to cool down due to excessively high ambient temperature. That is, when the heat dissipation component 5 is working, the real-time core temperature drops very slowly or even continues to rise. In this case, a high temperature warning should be issued, such as an audible and visual alarm or a fault code should be uploaded to the monitoring system to alert the user to the abnormal ambient temperature.

[0074] In summary, the heat dissipation component 5 can be controlled in the following ways:

[0075] S35. Calculate the cooling time based on the real-time core temperature, heat dissipation threshold and core temperature change gradient. If the cooling time is less than the working time of the heat dissipation component 5 within the heating cycle, the heat dissipation component 5 will perform heat dissipation work according to the working time. If the cooling time is greater than the working time, the heat dissipation component 5 will work according to the cooling time.

[0076] S36. If the core temperature change gradient is greater than the heat dissipation alarm threshold (-0.001℃ / s), it is determined that the heat dissipation component 5 cannot reduce the core temperature below the heat dissipation threshold and a high temperature fault warning is issued.

[0077] By monitoring the changing trend of the core temperature, the working time of the heating component 2 and the heat dissipation component 5 is dynamically adjusted to achieve closed-loop control of the core temperature.

[0078] Furthermore, when the heat dissipation component 5 fails to reduce the core temperature below the heat dissipation threshold, the cause of the fault should be analyzed in a timely manner so as to eliminate the fault of the detector in a timely manner and improve the maintainability of the detector.

[0079] Specifically, the identification of detector fault types can be achieved by combining the Internet of Things (IoT) and fault diagnosis models. During operation, the detector periodically collects operating status parameters and uploads them to the control center via network communication equipment. The control center then uses a pre-trained fault diagnosis model to perform fault diagnosis based on these operating status parameters. Figure 5 Specifically, it includes the following steps:

[0080] S361. Obtain real-time operating status data of the detector, including real-time core temperature, real-time ambient temperature, heating component voltage, heat dissipation component voltage, and detection component voltage. Filter and normalize the real-time operating status data. For example, Kalman filtering can be used to smooth noise fluctuations and fill in missing values.

[0081] S362. Run the isolated forest model, label the abnormal real-time running status data, and construct an abnormal status vector based on the abnormal running status data;

[0082] S363. Input the abnormal state vector into the fault diagnosis model and output the fault type probability.

[0083] The fault diagnosis model is obtained by training based on historical operating status data with labeled fault types.

[0084] In addition to the parameters mentioned above, real-time operating status data can also include power supply voltage and the detected raw concentration value. When the detector malfunctions, some or all of these parameters may become abnormal. Different types of malfunctions will cause different parameters to become abnormal. Therefore, these parameters can be used to comprehensively determine the type of malfunction of the detector. Deep learning algorithms are used to extract the data features corresponding to each type of malfunction based on historical operating status data, thereby achieving accurate analysis of the cause of the malfunction and improving the maintainability of the detector.

[0085] Considering the limited data processing capabilities of household combustible gas detectors, the real-time operating status data of the detector can be transmitted to the control center based on Internet of Things (IoT) communication technology. The control center can then perform fault diagnosis on the detector based on the real-time operating status parameters.

[0086] The detection method disclosed in this application combines temperature control with a temperature compensation algorithm to achieve dual temperature compensation for methane concentration detection results, thereby improving the accuracy of the detection results. Simultaneously, it employs an alternating intermittent control method for the heating component 2 and the cooling fan 51 to achieve low-cost control of the detector's core temperature. Furthermore, it calculates the core temperature gradient based on real-time core temperatures at multiple moments, determines the actual temperature change of the detector, and dynamically adjusts the operating time of the heating component 2 and the cooling fan 51 according to this actual temperature change, achieving closed-loop control.

[0087] The aforementioned detector can be applied not only to the detection of methane, but also to the detection of other combustible gases such as propane and acetylene. These gases, similar to methane, all have different absorption peak wavelengths, making them suitable for detection by the detector disclosed in this invention.

[0088] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A laser-based household combustible gas detector, characterized in that, include: Detection components, heating components, temperature measurement components, control components, and heat dissipation components; The detection component is used to emit and receive laser signals, and to measure the intensity of the received laser signals; The heating assembly is used to heat the inside of the detector in order to adjust the core temperature of the detector; The temperature measurement component includes an external temperature sensor and an internal temperature sensor. The external temperature sensor is used to measure the ambient temperature, and the internal temperature sensor is used to measure the core temperature of the detector. The heat dissipation component includes a cooling fan, which is used to reduce the core temperature of the detector. The control component is used to calculate the original concentration value of combustible gas based on the intensity of the laser signal, and to correct the original concentration value based on the core temperature and ambient temperature to obtain the true concentration value. The control component is also used to change the operating mode of the cooling fan and the heating component according to the core temperature and / or ambient temperature. When the core temperature is less than the heat dissipation threshold, the heating component works continuously. When the core temperature is greater than the heat dissipation threshold, the heating cycle and heating duty cycle are calculated according to the core temperature and the ideal operating temperature. During the heating cycle, the heating component and the cooling component work intermittently and alternately. Specifically, the control method of the control component includes the following steps: The system periodically acquires real-time ambient temperature, real-time core temperature of the detector, and raw concentration values ​​of combustible gases in the environment. The original concentration value is corrected based on the real-time core temperature and the real-time ambient temperature to obtain the corrected concentration value of combustible gas in the environment; Determine whether the real-time core temperature is less than the heat dissipation threshold. If yes, continuously heat the inside of the detector. If no, calculate the heating cycle and heating duty cycle based on the real-time core temperature and the ideal operating temperature. During the heating cycle, alternately heat and dissipate heat to the inside of the detector according to the heating duty cycle. When the real-time core temperature is greater than or equal to the heat dissipation threshold, the standard deviation surface array is interpolated using the real-time core temperature as the first coordinate and the real-time ambient temperature as the second coordinate to obtain the standard deviation corresponding to multiple different methane concentrations. The multiple standard deviations are interpolated based on the corrected concentration value, and the corrected concentration value is corrected a second time.

2. The detector according to claim 1, characterized in that, The original concentration value is corrected using the following steps: The offset caused by real-time core temperature changes is corrected by using the core temperature drift coefficient, and the offset caused by real-time ambient temperature changes is corrected by using the environmental interference coefficient, thus obtaining the corrected concentration value.

3. The detector according to claim 1, characterized in that, The standard deviation surface array is obtained through the following steps: In standard high and low temperature experiments, the methane concentration in the experimental environment was changed to obtain the standard deviation of the corrected concentration value and the true concentration value at different core temperatures and ambient temperatures. Using core temperature as the first coordinate, ambient temperature as the second coordinate, and the deviation between the corrected concentration value and the true concentration value as the third coordinate, a standard deviation surface is established using a cubic spline interpolation algorithm. Repeat the above steps to obtain multiple standard deviation surfaces corresponding to different methane concentrations, and form the standard deviation surface array according to the methane concentration values.

4. The detector according to claim 1, characterized in that, The detector's internal components are heated and cooled during the heating cycle through the following steps: Determine whether the real-time core temperature is greater than the ideal operating temperature. If not, the heating component will work first, and the working time of the heating component is the heating cycle multiplied by the heating duty cycle. If so, the heat dissipation component will work first, and the working time is the heating cycle minus the working time of the heating component.

5. The detector according to claim 1, characterized in that, The heating cycle and heating duty cycle are obtained through the following steps: Calculate the difference between the real-time core temperature and the ideal operating temperature, and multiply the difference by the temperature control coefficient to obtain the heating cycle; The heating duty cycle is calculated based on the calibration coefficient and the real-time core temperature.

6. The detector according to claim 5, characterized in that, The control method of the control component further includes the following steps: When the heat dissipation component is working, the core temperature change gradient is calculated based on the real-time core temperature collected multiple times. Determine whether the working time of the heat dissipation component within the heating cycle can reduce the core temperature below the heat dissipation threshold. If yes, the heat dissipation component and the heating component operate according to the heating cycle and heating duty cycle. If no, the working time of the heat dissipation component is recalculated based on the core temperature change gradient.

7. The detector according to claim 5, characterized in that, The control method of the control component further includes the following steps: The cooling time is calculated based on the real-time core temperature, the heat dissipation threshold, and the core temperature change gradient. If the cooling time is less than the working time of the heat dissipation component within the heating cycle, the heat dissipation component performs heat dissipation work according to the working time. If the cooling time is greater than the working time, the heat dissipation component works according to the cooling time. If the core temperature change gradient is greater than the heat dissipation alarm threshold, it is determined that the heat dissipation component cannot reduce the core temperature below the heat dissipation threshold, and a high temperature fault warning is issued.

8. The detector according to claim 7, characterized in that, When the core temperature change gradient exceeds the high temperature alarm threshold, the following steps are executed: The real-time operating status data of the detector is acquired, and Kalman filtering and normalization are performed on the real-time operating status data. The real-time operating status data includes real-time core temperature, real-time ambient temperature, heating component voltage, heat dissipation component voltage, and detection component voltage. Run the isolated forest model, label the abnormal real-time running status data, and construct an abnormal state vector based on the abnormal real-time running status data; The abnormal state vector is input into the fault diagnosis model, and the fault type probability is output. The fault diagnosis model is obtained by training based on historical operating status data with labeled fault types.

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