Method for linearization closed loop optimization of semiconductor gas sensor with adjustable voltage dynamic compensation

Abstract

The application discloses a linear closed-loop optimization method for a semiconductor gas sensor with adjustable voltage dynamic compensation, and relates to the technical field of gas detection.The method comprises the following steps: starting the semiconductor gas sensor in a clean air environment, outputting an initial test voltage sequence through a voltage regulator, collecting the sensor reference resistance under different voltages, screening the initial working voltage with the minimum resistance fluctuation, synchronously collecting the initial ambient temperature and humidity, calibrating the sensor reference resistance based on the preset temperature-resistance coefficient and humidity-resistance coefficient, and obtaining the initial reference resistance.Through dynamic adjustment of the working voltage and real-time compensation of the ambient temperature and humidity, the interference of the environmental factor fluctuation on the resistance characteristics of the sensitive material can be continuously offset, the linear relationship between the sensor output signal and the target gas concentration can be kept stable, and the dynamic optimization of the linearity in a complex environment is realized, so that more reliable basic data are provided for the gas concentration detection in an industrial scene.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gas detection, in particular to a linear closed-loop optimization method for a semiconductor gas sensor with adjustable voltage dynamic compensation. BACKGROUND

[0002] A semiconductor gas sensor is a device that analyzes gas composition or concentration by detecting changes in conductivity caused by gas adsorption. The core principle is that when gas molecules are adsorbed on the surface of a semiconductor, an oxidation / reduction reaction occurs, causing a change in the electrical conductivity of the material. For example, a reducing gas reacts with adsorbed oxygen, reducing the surface potential barrier and causing the sensor resistance to decrease, thus enabling gas detection.

[0003] Existing semiconductor gas sensors generally use a fixed operating voltage. Environmental temperature fluctuations can change the chemical reaction rate of the sensitive material, humidity changes can cause the material to absorb moisture and resist drift, and long-term use can cause the structure of the sensitive layer to change. Therefore, the linear relationship between the sensor output signal and the target gas concentration is continuously disrupted, causing signal nonlinearity deviations to occur in wide concentration range detection, and the deviation gradually increases with the extension of use time, which cannot meet the needs of high-precision, long-term stable monitoring in industrial environments. SUMMARY

[0004] To overcome the shortcomings of the prior art, the present application provides a linear closed-loop optimization method for a semiconductor gas sensor with adjustable voltage dynamic compensation, which solves the problems mentioned in the background art.

[0005] To achieve the above purpose, the present application realizes the following technical scheme: a linear closed-loop optimization method for a semiconductor gas sensor with adjustable voltage dynamic compensation, comprising the following steps:

[0006] A1, control the semiconductor gas sensor to start in a clean air environment, output an initial test voltage sequence through a voltage regulator, collect the sensor reference resistance under different voltages, select the initial operating voltage with the smallest resistance fluctuation, simultaneously collect the initial environmental temperature and humidity, calibrate the sensor reference resistance based on the preset temperature and resistance coefficient and humidity and resistance coefficient, and obtain the initial reference resistance;

[0007] A2, continuously collect the real-time resistance, environmental temperature, environmental humidity and target gas concentration change rate of the semiconductor gas sensor in the target gas environment after calibration, calculate the real-time resistance change, and record the current operating voltage of the semiconductor gas sensor;

[0008] A3, based on the linear relationship between the real-time resistance change amount and the initial reference resistance, the current linearity deviation is calculated by a linear fitting algorithm, when the linearity deviation exceeds a preset threshold, a temperature compensation voltage, a humidity compensation voltage and a material aging compensation voltage are calculated respectively;

[0009] A4, based on the linearity deviation, the temperature compensation voltage, the humidity compensation voltage and the material aging compensation voltage, the total voltage adjustment amount is calculated by a closed-loop control algorithm, the adjusted voltage is output, and the reference resistance is updated to the calibration value under the current voltage;

[0010] A5, the data acquisition period is dynamically adjusted according to the gas concentration change rate, the high-low speed sampling mode switching is realized, steps A2 to A4 are continuously and circularly executed, the linearity deviation is monitored in real time and dynamically corrected, and the linearity deviation is stable within the preset threshold.

[0011] Preferably, the generation and screening method of the initial test voltage sequence in step A1 is specifically as follows:

[0012] A11, a voltage sequence of 0.5V-5V is generated with 0.1V as a step, the reference resistance of the semiconductor gas sensor is continuously collected for 10 times after each voltage point is kept stable for 30s;

[0013] A12, the resistance standard deviation under a single voltage is calculated, and the voltage with the resistance standard deviation is selected as the initial working voltage:

[0014] Wherein, is the resistance standard deviation, is the average value of 10 measurements of the reference resistance of the semiconductor gas sensor.

[0015] Preferably, the linear fitting algorithm in step A3 is specifically as follows:

[0016] A linear model is established with the real-time resistance change amount as the dependent variable and the initial reference resistance as the independent variable:

[0017] ;

[0018] Wherein, is the dependent variable, is the independent variable, and are fitting parameters;

[0019] The fitting parameters are specifically as follows:

[0020] ;

[0021] ;

[0022] Wherein,​ The number of data sets for fitting is in the range of 5≤ ≤10;

[0023] The linearity deviation of the gas sensor is specifically:

[0024] ;

[0025] Wherein, is the slope of the target linearity.

[0026] Preferably, the closed-loop control algorithm in step A4 is a PID control algorithm, and specifically, the calculation formula of the total voltage adjustment amount is:

[0027] ;

[0028] Wherein, is the proportional coefficient, is the integral coefficient, is the differential coefficient, is the linearity deviation, are the temperature compensation voltage, humidity compensation voltage and material aging compensation voltage respectively.

[0029] Preferably, the adaptive adjustment method of the collection period in step A5 is:

[0030] When , the collection period is set to 5-10s, and when , the collection period is switched to 0.5-1s, and the current state is saved through the data buffer area to ensure continuity when switching;

[0031] Wherein, is the instantaneous change of the target gas concentration, is the small time interval experienced by the corresponding concentration change , unit: s.

[0032] Preferably, the linearity abnormality early warning method is also included in step A5:

[0033] When the linearity deviation , a first-level warning is triggered, only abnormal data is recorded and stored;

[0034] When the linearity deviation , a second-level warning is triggered, and a local audible and visual alarm is started;

[0035] When the linearity deviation , a third-level warning is triggered, and the warning information is uploaded through wireless communication.

[0036] Preferably, the local audible and visual alarm includes: a buzzer chirp and an alarm indicator light flicker;

[0037] The early warning information comprises a sensor device ID, an abnormal time and a real-time parameter.

[0038] Preferably, the real-time humidity acquisition and processing method in step A2 is as follows:

[0039] By integrating a humidity sensor in the semiconductor gas sensor, the ambient humidity is synchronously acquired, a sliding average algorithm is used for filtering, the filtering window is 3-5 groups of data, and the filtered data are used for calculating the humidity compensation voltage.

[0040] Preferably, the step A5 further comprises a closed-loop adjustment state recording method:

[0041] After each completion of voltage adjustment, the execution time of the adjustment operation, the working voltage values before and after adjustment and the linearity deviation state at the corresponding time are automatically recorded, and the recording contents are stored in a non-volatile storage unit in chronological order, and the storage period is consistent with the actual working period of the sensor.

[0042] Preferably, the step A4 further comprises a voltage adjustment safety limit method:

[0043] When the absolute value of the total voltage adjustment amount calculated exceeds 30% of the initial working voltage, the actual executed voltage adjustment amount is limited to 30% of the initial working voltage, at the same time, the adjustment is marked as a limited state, and the environmental parameters are preferentially collected in the subsequent real-time monitoring stage to reevaluate the linearity deviation.

[0044] The application provides a semiconductor gas sensor linearity closed-loop optimization method with adjustable voltage dynamic compensation.

[0045] (1) By dynamically adjusting the working voltage, combining with real-time compensation of the environmental temperature and humidity, the disturbance of the environmental factor fluctuation on the resistance characteristics of the sensitive material can be continuously offset, the linear relationship between the sensor output signal and the target gas concentration is kept stable, the dynamic optimization of the linearity in a complex environment is realized, and more reliable basic data for gas concentration detection in an industrial scene is provided, and the high-precision monitoring requirement is met.

[0046] (2) By continuously updating the reference resistance and dynamically correcting the working voltage through the closed-loop mechanism, the change of the sensitive layer structure caused by aging in long-term use of the material can be effectively responded, the continuous deterioration of the linear relationship is alleviated, the performance stability of the sensor in the whole life cycle is realized, and the situation that the device needs to be frequently calibrated or replaced due to the too large linearity deviation is reduced, and the long-term use cost is reduced.

[0047] (3) Through continuous cycle monitoring and real-time adjustment, the sampling mode can be dynamically adapted according to the gas concentration change, the linear detection state can be maintained when the concentration rapidly fluctuates, the adaptive response to different concentration change scenes is realized, and then the dual requirements of real-time and accuracy of gas detection in an industrial environment are met, and the overall reliability of the monitoring system is improved. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 A method flowchart of the semiconductor gas sensor linearity closed-loop optimization method of the adjustable voltage dynamic compensation;

[0049] Figure 2 A method step diagram of the semiconductor gas sensor linearity closed-loop optimization method of the adjustable voltage dynamic compensation. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0051] Embodiment 1

[0052] Please refer to Figures 1-2 The present application provides a semiconductor gas sensor linearity closed-loop optimization method of adjustable voltage dynamic compensation. To achieve the above purpose, the present application is implemented by the following technical solutions: comprising the following steps:

[0053] A1, control the semiconductor gas sensor to start in a clean air environment, output an initial test voltage sequence through a voltage regulator, collect the sensor reference resistance under different voltages, select the initial working voltage with the smallest resistance fluctuation, simultaneously collect the initial environment temperature and humidity, calibrate the sensor reference resistance based on the preset temperature and resistance coefficient and humidity and resistance coefficient, and obtain the initial reference resistance;

[0054] A2, continuously collect the real-time resistance, environment temperature, environment humidity and target gas concentration change rate of the semiconductor gas sensor in the target gas environment after calibration, calculate the real-time resistance change, and record the current working voltage of the semiconductor gas sensor;

[0055] A3, based on the linear relationship between the real-time resistance change and the initial reference resistance, calculate the current linearity deviation through a linear fitting algorithm, calculate the temperature compensation voltage, humidity compensation voltage and material aging compensation voltage when the linearity deviation exceeds the preset threshold.

[0056] A4, based on the linearity deviation, temperature compensation voltage, humidity compensation voltage and material aging compensation voltage, the total voltage adjustment amount is calculated by a closed-loop control algorithm, the adjusted voltage is output, and the reference resistance is updated to the calibration value under the current voltage;

[0057] A5, dynamically adjust the data acquisition period according to the gas concentration change rate, realize high-low speed sampling mode switching, continuously execute steps A2 to A4, real-time monitor the linearity deviation and dynamically correct the working voltage until the linearity deviation is stable within the preset threshold.

[0058] In this embodiment, after the sensor is started in a clean air environment, the voltage regulator outputs a series of test voltages according to the preset rules, each voltage value maintains a stable working state for a period of time, and the reference resistance of the sensor is continuously collected during this period. By comparing the stability of the resistance under different voltages, the voltage with the smallest resistance fluctuation is selected as the initial working voltage. At the same time, the environmental temperature and humidity at this time are recorded, and the reference resistance is calibrated according to the influence law of temperature and humidity on resistance before the sensor is factory calibrated, to obtain the reference resistance value in the initial state, and to establish a reference for subsequent detection.

[0059] After the sensor enters the target gas environment, the real-time resistance change of the sensor is continuously monitored, and the current temperature, humidity, and target gas concentration change rate are obtained through the integrated environmental sensor. The difference between the real-time resistance and the initial reference resistance is calculated as a key parameter reflecting the gas concentration, and the current working voltage of the sensor is recorded to provide a basis for subsequent adjustment.

[0060] Based on the linear relationship between the real-time resistance change and the initial reference resistance, the current linearity deviation is evaluated by analyzing the corresponding relationship between the two. When the deviation exceeds the preset acceptable range, the voltage values that need to be compensated are calculated respectively according to the environmental temperature change, humidity fluctuation, and material aging caused by long-term use of the sensor. The calculation of these compensation values is based on the correlation between temperature, humidity, aging degree and resistance change determined through experiments in the early stage.

[0061] Combined with the linearity deviation and each compensation voltage, the total voltage adjustment amount is calculated through a closed-loop control logic, and then the adjusted voltage is output to the sensor, and the reference resistance at this time is updated to the calibration value under this voltage, ensuring that the subsequent detection is always based on the current state, forming a dynamic feedback closed loop.

[0062] According to the speed of the target gas concentration change, the frequency of data acquisition is automatically adjusted. When the concentration changes gently, the sampling frequency is reduced to reduce energy consumption. When the concentration changes dramatically, the sampling frequency is increased to ensure the real-time nature of the data. In this process, the linearity deviation is continuously monitored and the working voltage is adjusted until the deviation stabilizes within the preset range, ensuring that the sensor output signal and gas concentration maintain a stable linear relationship.

[0063] Through phased system initialization, real-time monitoring and dynamic adjustment, real-time response to environmental factors and changes in the state of the sensor itself is achieved, ensuring that the sensor always maintains stable linear output characteristics in complex industrial environments, providing reliable protection for high-precision gas concentration detection, especially in high-safety chemical and mining scenarios.

[0064] Embodiment 2

[0065] Specifically: refer to Figure 1 , the generation and screening method of the initial test voltage sequence in step A1 is as follows:

[0066] A11, generate a voltage sequence of 0.5V-5V with a step of 0.1V, and after each voltage point is kept stable for 30s, continuously collect the reference resistance of the semiconductor gas sensor for 10 times;

[0067] A12, calculate the resistance standard deviation under a single voltage, and select the voltage with a resistance standard deviation of: as the initial working voltage;

[0068] wherein, is the resistance standard deviation, is the average value of 10 measurements of the reference resistance of the semiconductor gas sensor.

[0069] The linear fitting algorithm in step A3 is as follows:

[0070] A linear model is established with the real-time resistance change as the dependent variable and the initial reference resistance as the independent variable:

[0071]

[0072] wherein, is the dependent variable, is the independent variable, and are fitting parameters;

[0073] The fitting parameters are as follows:

[0074]

[0075]

[0076] wherein, is the number of fitted data sets, and the range is 5≤ ≤10;

[0077] It can be seen that the linearity deviation of the gas sensor is specifically:

[0078]

[0079] wherein, is the slope of the target linearity.

[0080] The real-time humidity acquisition and processing method in step A2 is:

[0081] By integrating a humidity sensor in the semiconductor gas sensor, the ambient humidity is synchronously acquired, a sliding average algorithm is used for filtering, the filtering window is 3-5 groups of data, and the filtered data is used for humidity compensation voltage calculation.

[0082] In this embodiment, the voltage regulator generates a series of voltage values from low to high with fixed small steps, covering the normal working voltage range of the sensor. After each voltage value is output, the sensor needs to go through a stable period, and after the resistance value is stable, the reference resistance is continuously collected multiple times. By calculating the dispersion degree of multiple resistance measurement values under the same voltage, the voltage with the smallest dispersion degree is selected as the initial working voltage. This process ensures that the sensor works in the most stable voltage state from the start-up stage, reducing the influence of initial errors on subsequent detection.

[0083] In real-time detection, the corresponding relationship between the real-time resistance change of the sensor and the initial reference resistance is continuously recorded, multiple groups of continuous corresponding data are selected, the distribution rule of these data is analyzed, and the linear matching degree between the two is evaluated. When the linear matching degree deviates from the preset ideal state, it is determined that the linearity deviation exceeds the threshold, triggering the subsequent compensation mechanism.

[0084] The ambient humidity is synchronously acquired by the integrated humidity sensor. In order to reduce the influence of instantaneous fluctuations on humidity data, the average value after continuous multiple acquisitions is used for filtering processing. The filtered humidity data is used for subsequent humidity compensation voltage calculation, ensuring that the influence of humidity on the sensor resistance is accurately corrected, and avoiding detection deviation caused by sudden changes in humidity.

[0085] By refining the operation process of initial voltage selection, the stability of the sensor working point is ensured; by simplifying the execution logic of linear relationship evaluation, the efficiency of deviation judgment is improved; by optimizing the acquisition and processing method of humidity data, the environmental adaptability is enhanced. The three work together to make the sensor maintain stable linear output in low-concentration methane detection, meeting the precision requirements of civil gas leakage detection.

[0086] Embodiment 3

[0087] Specifically, referring to Figure 1 , the closed-loop control algorithm in step A4 is a PID control algorithm, specifically, the calculation formula of the total voltage adjustment amount is:

[0088]

[0089] wherein, is a proportional coefficient, is an integral coefficient, is a differential coefficient, is a linearity deviation, are temperature compensation voltage, humidity compensation voltage and material aging compensation voltage respectively.

[0090] The voltage adjustment safety limiting method is also included in step A4:

[0091] When the absolute value of the calculated total voltage adjustment amount exceeds 30% of the initial working voltage, the actually executed voltage adjustment amount is limited to 30% of the initial working voltage, and this adjustment is marked as a limited state, and the environmental parameters are preferentially collected in the subsequent real-time monitoring stage to re-evaluate the linearity deviation;

[0092] In this embodiment, when the linearity deviation exceeds the threshold, the semiconductor gas sensor system comprehensively considers the current linearity deviation degree, as well as the temperature, humidity and material aging corresponding compensation voltages, and calculates the total voltage adjustment amount required by the pre-set closed-loop control logic, wherein the proportional link is used for fast response to the current deviation, the integral link is used for eliminating the long-term accumulated deviation, and the differential link is used for suppressing the fluctuation in the adjustment process, and the three links cooperate to realize the smooth adjustment of the voltage. The adjusted voltage is output to the sensor in real time, and the reference resistance is updated to the calibration value at this voltage, forming a complete feedback closed loop;

[0093] To avoid damage to the sensitive material of the sensor caused by severe voltage fluctuations, a maximum allowed adjustment amplitude is set, when the calculated total voltage adjustment amount exceeds the amplitude, the actually executed adjustment amount will be limited within the maximum allowed range, and this adjustment is marked as a limited state, in the subsequent detection process, the system will preferentially collect environmental parameters and sensor state data, re-evaluate the reason for the linearity deviation, and further adjust after confirming the safety, this mechanism ensures the physical safety of the sensor in the dynamic adjustment process, and avoids the performance degradation of the material caused by excessive adjustment;

[0094] The closed-loop control logic achieves the accuracy and stability of voltage adjustment through multi-stage collaboration. It can quickly correct linearity deviations and avoid oscillations during the adjustment process. The safety limiting mechanism provides physical protection for the sensor and extends the service life of the device. It is especially suitable for industrial waste gas monitoring scenarios that require long-term continuous operation.

[0095] The specific formulas for calculating temperature compensation voltage, humidity compensation voltage, and material aging compensation voltage are as follows:

[0096] The calculation method for temperature compensation voltage is as follows:

[0097]

[0098] in, The temperature coefficient is obtained by measuring the sensor's temperature in clean air. and resistance at time and Based on the Boltzmann equation fitting, we obtain:

[0099]

[0100] The calculation method for humidity compensation voltage is as follows:

[0101]

[0102] in, The humidity coefficient is determined using the following method: under constant temperature conditions of 25℃ and a gas concentration of 0ppm, samples were collected... , , and Changes in resistance in the environment The linear regression equation yields:

[0103]

[0104] The value range is 0.001~0.003 / (%RH);

[0105] The calculation method for material aging compensation voltage is as follows:

[0106]

[0107] in, To predict the resistance, it is calculated based on an exponential decay model, specifically:

[0108]

[0109] Aging coefficient By the data collected at zero o'clock every day, the least square method is used to fit the update, The working days of the sensor are accumulated;

[0110] The temperature compensation voltage, the humidity compensation voltage and the material aging compensation voltage are the core correction amounts of the linear closed-loop optimization method to offset multi-factor interference. The three work together to maintain the stability of the sensor linearity, and together as a component of the total voltage adjustment amount, real-time correct the working voltage in the closed-loop control, to ensure that the sensor always maintains stable linear output under complex conditions such as temperature fluctuations, humidity changes and material aging.

[0111] Embodiment 4

[0112] Specifically, referring to Figure 1 , the adaptive adjustment method of the collection period in step A5 is:

[0113] When , the collection period is set to 5-10s, when , the collection period is switched to 0.5-1s, and the current state is saved through the data buffer area to ensure continuity when switching;

[0114] Wherein, is the instantaneous change of the target gas concentration, is the small time interval experienced by the corresponding concentration change , unit is s.

[0115] The linear abnormality warning method in step A5 also includes:

[0116] When the linearity deviation , trigger a first-level warning, only record abnormal data and store the data;

[0117] When the linearity deviation , trigger a second-level warning, start local audible and visual alarm;

[0118] When the linearity deviation , trigger a third-level warning, upload the warning information through wireless communication.

[0119] The local audible and visual alarm includes: buzzer ringing and alarm indicator light flashing;

[0120] The warning information includes: sensor device ID, abnormal time and real-time parameters.

[0121] The closed-loop adjustment state recording method in step A5 also includes:

[0122] ​After each voltage adjustment, the execution time of the adjustment operation, the working voltage values before and after adjustment, and the linearity deviation state at the corresponding time are automatically recorded and stored in the non-volatile storage unit in chronological order, and the storage period is consistent with the actual working period of the sensor;

[0123] In this embodiment,

[0124] The system continuously monitors the change speed of the target gas concentration. When the concentration changes slowly, it automatically switches to a low-speed sampling mode, prolongs the time interval of data collection, and reduces unnecessary energy consumption. When the concentration changes rapidly, it immediately switches to a high-speed sampling mode, shortens the collection interval, and ensures the capture of rapid changes in concentration. During the mode switching process, the system saves the current detection state and collected data through the data buffer area, continues collection from the breakpoint after switching is completed, ensures the continuity and integrity of the data sequence, and avoids information loss caused by mode switching;

[0125] The system sets a three-level early warning mechanism according to the severity of the linearity deviation. When the deviation slightly exceeds the threshold, only abnormal information is recorded in the storage unit for subsequent maintenance and analysis. When the deviation further increases, a local audible and visual alarm is started to remind the on-site staff to check. When the deviation seriously exceeds the standard, the abnormal information is uploaded to the remote monitoring platform through the wireless communication module, including the device identification, the time of abnormal occurrence, and the current environmental parameters, so that the remote operation and maintenance personnel can intervene and handle in time;

[0126] The adaptive adjustment of the collection period balances the detection real-time performance and energy consumption control, and is suitable for portable devices powered by batteries. The hierarchical early warning mechanism realizes gradient management of abnormal risks through differentiated response methods, avoids overreaction to slight abnormalities, ensures timely handling of serious abnormalities, and provides multi-level safety protection for gas monitoring in high-risk environments.

[0127] Specifically, first, initialization calibration, the sensor starts in a clean air environment, output a series of test voltage through the voltage regulator, filter the initial working voltage of the minimum resistance fluctuation, synchronous acquisition of initial temperature and humidity, according to the preset temperature and humidity influence law of resistance calibration reference resistance, establish the initial reference, then enter real-time monitoring, sensor continuously collect real-time resistance, environmental temperature and humidity and target gas concentration rate of change, calculate the difference between real-time resistance and initial reference resistance, record the current working voltage, then linear evaluation, based on the linear relationship between the resistance change and the reference resistance to determine whether the deviation is over the threshold, if over the threshold, then calculate the temperature, humidity, material aging corresponding compensation voltage, and then through the closed loop control to calculate the total voltage adjustment, output the adjusted voltage and update the reference resistance, form a dynamic feedback, finally adaptive optimization, according to the gas concentration rate of change switch high and low speed sampling mode, continuous cycle monitoring and adjustment, until the linear deviation is stable within the preset threshold, realize the long-term stability of the sensor linearity in complex environment.

[0128] While the embodiments of the application have been illustrated and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and alterations can be made therein without departing from the spirit and scope of the application.

Claims

1. A method for closed loop optimization of linearity of a semiconductor gas sensor with adjustable voltage dynamic compensation, characterized in that: The method comprises the following steps: A1, controlling the semiconductor gas sensor to start in a clean air environment, outputting an initial test voltage sequence through a voltage regulator, collecting the sensor reference resistance under different voltages, screening out the initial working voltage with the smallest resistance fluctuation, synchronously collecting the initial environmental temperature and humidity, calibrating the sensor reference resistance based on the preset temperature and resistance coefficient and humidity and resistance coefficient to obtain the initial reference resistance; A2, continuously collecting the real-time resistance, environmental temperature, environmental humidity and target gas concentration change rate of the semiconductor gas sensor in the target gas environment after calibration, calculating the real-time resistance change amount, and recording the current working voltage of the semiconductor gas sensor; A3, based on the linear relationship between the real-time resistance change amount and the initial reference resistance, calculating the current linearity deviation through a linear fitting algorithm, and calculating the temperature compensation voltage, humidity compensation voltage and material aging compensation voltage when the linearity deviation exceeds the preset threshold; A4, based on the linearity deviation, temperature compensation voltage, humidity compensation voltage and material aging compensation voltage, calculating the total voltage adjustment amount through a closed-loop control algorithm, outputting the adjusted voltage, and updating the reference resistance to the calibrated value under the current voltage; A5, dynamically adjusting the data collection period according to the gas concentration change rate, realizing the switching of high and low speed sampling modes, continuously and cyclically executing steps A2 to A4, real-time monitoring the linearity deviation and dynamically correcting the working voltage until the linearity deviation is stable within the preset threshold; The linear fitting algorithm in step A3 is specifically: A linear model is established with the real-time resistance change amount as the dependent variable and the initial reference resistance as the independent variable: ； wherein, is the dependent variable, is the independent variable, and are fitting parameters; The fitting parameters are specifically: ； ； wherein, is the number of data sets to fit, ranging from 5≤ ≤10; It can be seen that the linearity deviation of the gas sensor is specifically: ； wherein is the slope of the target line; The closed-loop control algorithm in step A4 is a PID control algorithm, and the calculation formula of the total voltage adjustment amount is: ； wherein, is a proportional coefficient, is an integral coefficient, is a derivative coefficient, is a linearity deviation, are a temperature compensation voltage, a humidity compensation voltage and a material aging compensation voltage, respectively; The adaptive adjustment method of the collection period in step A5 is: When the acquisition cycle is set to 5-10s, when the acquisition cycle is switched to 0.5-1s, and the current state is saved through a data buffer to ensure continuity when switching. wherein, is the instantaneous change in concentration of the target gas, is the corresponding change in concentration is the elapsed micro time interval in s.

2. The method of claim 1, wherein the method further comprises: determining a voltage adjustment value for the semiconductor gas sensor based on the determined voltage adjustment value and the determined linearity value. The generation and screening method of the initial test voltage sequence in step A1 is specifically as follows: A11, generate a voltage sequence of 0.5V-5V with a step of 0.1V, and continuously collect the reference resistance of the semiconductor gas sensor for 10 times after maintaining stable work for 30s at each voltage point; A12, calculate the standard deviation of resistance under single voltage, select the standard deviation of resistance as: the voltage as the initial operating voltage; wherein, is the resistance standard deviation, is the semiconductor gas sensor reference resistance 10 measurement average value.

3. The closed-loop optimization method for linearity of a semiconductor gas sensor with adjustable voltage dynamic compensation according to claim 1, characterized in that: The step A5 also includes a linearity abnormality early warning method: When the linearity deviation Level one early warning is triggered, only record abnormal data and store data; When the linearity deviation The secondary early warning is triggered, and the local sound and light alarm is started. When the linearity deviation The third level warning is triggered, and the warning information is uploaded through wireless communication.

4. The method of claim 3, wherein the method further comprises: determining a voltage offset for the semiconductor gas sensor; and applying the voltage offset to the voltage applied to the semiconductor gas sensor.

5. The method of claim 3, wherein the method further comprises: determining a voltage offset for the semiconductor gas sensor; and applying the voltage offset to the voltage applied to the semiconductor gas sensor. The local sound-light alarm includes: buzzer ringing and alarm indicator light flickering; The early warning information includes: sensor device ID, abnormal time and real-time parameters.

5. The closed-loop optimization method for linearity of a semiconductor gas sensor with adjustable voltage dynamic compensation according to claim 1, characterized in that: The real-time humidity collection and processing method in step A2 is: The humidity sensor is integrated in the semiconductor gas sensor, the environmental humidity is synchronously collected, the sliding average algorithm is used for filtering, the filter window is 3-5 groups of data, and the filtered data are used for calculating the humidity compensation voltage.

6. The method of claim 1, wherein the method further comprises: determining a voltage offset for the semiconductor gas sensor; and applying the voltage offset to the voltage applied to the semiconductor gas sensor. The step A5 also includes a closed-loop adjustment state recording method: After each voltage adjustment is completed, the execution time of the adjustment operation, the working voltage values before and after the adjustment, and the linearity deviation state at the corresponding time are automatically recorded, and the recording contents are stored in the non-volatile storage unit in chronological order, and the storage period is consistent with the actual working period of the sensor.

7. The method for closed-loop optimization of linearity of a semiconductor gas sensor with adjustable voltage dynamic compensation according to claim 1, characterized in that: The step A4 also includes a voltage adjustment safety limiting method: When the absolute value of the total voltage adjustment amount calculated exceeds 30% of the initial operating voltage, the voltage adjustment amount actually performed is limited to 30% of the initial operating voltage, while marking this adjustment as a limited state, and the environmental parameters are preferentially collected in the subsequent real-time monitoring stage to reevaluate the linearity deviation.

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