Method for correcting long-term drift of a gas sensor and correction system

Abstract

The application relates to the technical field of detection, and discloses a correction method and a correction system for long-term drift of a gas sensor. The correction method comprises the following steps: after the gas sensor is heated to a first preset temperature and maintained for a preset time, the heating of the gas sensor is stopped; the voltage of a matching resistance of the gas sensor under a preset condition is measured, wherein the preset condition comprises a second preset temperature, and the second preset temperature is less than the first preset temperature; a gas-sensitive resistance change rate is determined according to a power supply voltage, the voltage of the matching resistance under the preset condition and a calibrated gas-sensitive resistance, wherein the calibrated gas-sensitive resistance is a gas-sensitive resistance calibration value of the gas sensor under the preset condition; and corresponding correction operation is performed on the gas sensor according to the gas-sensitive resistance change rate. The application can correct the long-term drift of the gas sensor in a complex gas environment in an application site.

Description

Technical Field

[0001] This invention relates to the field of detection technology, and more specifically to a method and system for correcting long-term drift of a gas sensor. Background Technology

[0002] Sensors, as a primary means of information acquisition, are an indispensable shared key technology in the intelligent era. Gas sensors, as sensing elements for identifying gas types and concentrations, have wide applications in manned spaceflight, safety monitoring, environmental monitoring, artificial intelligence, and the Internet of Things. MEMS gas sensors, due to their small size, low power consumption, and low cost, are increasingly used in production and daily life. MEMS gas sensors are commonly used for gas concentration detection. During application, they are inevitably affected by external environmental factors, leading to drift and a decrease in gas concentration detection accuracy. The reasons for this decrease in accuracy include short-term factors such as temperature and humidity, as well as reversible drift after long-term storage and aging drift due to long-term use.

[0003] In existing technologies, gas sensors are calibrated in a dedicated calibration test environment, requiring the additional setup of a high-precision standard gas sensor and the injection of standard gas. This approach is unsuitable for gas sensors already in field use or those that cannot be disassembled. Furthermore, the concentration of the detected gas may remain unknown at the application site, making it impossible to correct for long-term drift in gas sensors already in field use. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for correcting long-term drift of a gas sensor, which can perform long-term reversible drift or long-term aging drift correction on gas sensors in complex gas environments at the application site.

[0005] To achieve the above objectives, a first aspect of the present invention provides a method for correcting reversible drift of a gas sensor. The method includes: heating the gas sensor to a first preset temperature and maintaining it for a preset time, then stopping the heating of the gas sensor; measuring the voltage of a matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature and the second preset temperature being lower than the first preset temperature; determining a rate of change of a gas-sensitive resistor based on a power supply voltage, the voltage of the matching resistor under the preset conditions, and a calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the calibrated value of the gas sensor under the preset conditions; and performing a corresponding correction operation on the gas sensor based on the rate of change of the gas-sensitive resistor.

[0006] Preferably, determining the rate of change of the gas-sensitive resistor includes: determining the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and determining the rate of change of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0007] Preferably, the corresponding calibration operation on the gas sensor includes: determining that the reversible drift has disappeared when the rate of change of the gas resistivity is less than or equal to a preset value; or heating the gas sensor to the first preset temperature and maintaining it for the preset time when the rate of change of the gas resistivity is greater than the preset value, and repeating the calibration method.

[0008] Preferably, the calibration method further includes: calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; determining the functional relationship between the gas-sensitive resistor and the variable parameters; and determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0009] Preferably, the preset conditions also include preset humidity.

[0010] Through the above technical solution, this invention creatively firstly, after heating the gas sensor to a first preset temperature and maintaining it for a preset time, stops heating the gas sensor; secondly, it measures the voltage of the matching resistor of the gas sensor under preset conditions; then, based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor, it determines the rate of change of the gas-sensitive resistor; finally, based on the rate of change of the gas-sensitive resistor, it performs a corresponding calibration operation on the gas sensor. This invention can perform long-term reversible drift correction of gas sensors in complex gas environments at the application site.

[0011] A second aspect of the present invention provides a method for correcting aging drift of a gas sensor. The method includes: acquiring the gas-sensitive resistor of the gas sensor under operating conditions, wherein the operating conditions include a first preset temperature; measuring the voltage of a matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature, and the second preset temperature is lower than the first preset temperature; determining a change value of the gas-sensitive resistor based on a power supply voltage, the voltage of the matching resistor under the preset conditions, and a calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the calibrated value of the gas-sensitive resistor of the gas sensor under the preset conditions; determining the gas-sensitive resistor drift of the gas sensor under operating conditions based on the gas-sensitive resistor of the gas sensor under operating conditions, the gas-sensitive resistor of the gas sensor under the preset conditions, and the change value of the gas-sensitive resistor; and performing a corresponding correction operation on the gas sensor based on the gas-sensitive resistor drift.

[0012] Preferably, determining the change value of the gas-sensitive resistor includes: determining the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and determining the change value of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0013] Preferably, determining the gas-sensitive resistor drift of the gas sensor under the operating conditions includes: based on the gas-sensitive resistor R of the gas sensor under the operating conditions. H The gas sensor, under the preset conditions, uses the gas-sensitive resistor R1, the change value of the gas-sensitive resistor ΔR1, and the following formula to determine the drift amount ΔR of the gas-sensitive resistor. H , Where a and b are the first constant and the second constant, respectively.

[0014] Preferably, performing the corresponding calibration operation on the gas sensor includes: calibrating the gas sensor according to the gas resistor drift when the gas resistor drift is less than or equal to a threshold; or sending fault information when the gas resistor drift is greater than the threshold.

[0015] Preferably, the calibration method further includes: calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; determining the functional relationship between the gas-sensitive resistor and the variable parameters; and determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0016] Preferably, the preset conditions also include preset humidity.

[0017] Preferably, obtaining the gas-sensitive resistor of the gas sensor under operating conditions includes: determining the gas-sensitive resistor of the gas sensor under operating conditions based on the power supply voltage, the resistance value of the matching resistor of the gas sensor, and the voltage of the matching resistor under operating conditions. Before performing the step of measuring the voltage of the matching resistor of the gas sensor under preset conditions, the calibration method further includes: stopping the heating of the gas sensor.

[0018] Through the above technical solution, this invention creatively obtains the gas-sensitive resistor of the gas sensor under operating conditions; secondly, it measures the voltage of the matching resistor of the gas sensor under preset conditions; next, it determines the change value of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under preset conditions, and the calibrated gas-sensitive resistor; then, it determines the gas-sensitive resistor drift amount under operating conditions based on the gas-sensitive resistor of the gas sensor under operating conditions, the gas-sensitive resistor of the gas sensor under preset conditions, and the change value of the gas-sensitive resistor; finally, it performs a corresponding calibration operation on the gas sensor based on the gas-sensitive resistor drift amount. This invention can perform long-term aging drift calibration of gas sensors in complex gas environments at the application site.

[0019] A third aspect of the present invention provides a correction system for reversible drift of a gas sensor, the correction system comprising: a heating device for stopping heating the gas sensor after heating it to a first preset temperature and maintaining it for a preset time; a voltage measuring device for measuring the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature and the second preset temperature is less than the first preset temperature; and a control device for performing the following operations: determining the rate of change of a gas-sensitive resistor based on a power supply voltage, the voltage of the matching resistor under the preset conditions, and a calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the calibrated value of the gas sensor under the preset conditions; and performing a corresponding correction operation on the gas sensor based on the rate of change of the gas-sensitive resistor.

[0020] Preferably, the control device includes: a first determining module, configured to determine the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and a second determining module, configured to determine the gas-sensitive resistor change rate based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0021] Preferably, the corresponding calibration operation on the gas sensor includes: determining that the reversible drift has disappeared when the rate of change of the gas resistivity is less than or equal to a preset value; or controlling the heating device to heat the gas sensor to the first preset temperature and maintain it for the preset time when the rate of change of the gas resistivity is greater than the preset value, and repeating the calibration process through the calibration system.

[0022] Preferably, the calibration system further includes: a calibration device for calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; a first determining device for determining the functional relationship between the gas-sensitive resistor and the variable parameters; and a second determining device for determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0023] Preferably, the preset conditions also include preset humidity.

[0024] For specific details and benefits of the gas sensor reversible drift correction system provided in the embodiments of the present invention, please refer to the above description of the gas sensor reversible drift correction method, which will not be repeated here.

[0025] A fourth aspect of the present invention provides a correction system for aging drift of a gas sensor. The correction system includes: a control device for acquiring the gas-sensitive resistor of the gas sensor under operating conditions, wherein the operating conditions include a first preset temperature; a heating device for stopping heating of the gas sensor; and a voltage measuring device for measuring the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature, and the second preset temperature is lower than the first preset temperature. The control device is further configured to perform the following operations: determine a change value of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the calibrated value of the gas-sensitive resistor of the gas sensor under the preset conditions; determine the gas-sensitive resistor drift of the gas sensor under operating conditions based on the gas-sensitive resistor of the gas sensor under the operating conditions, the gas-sensitive resistor of the gas sensor under the preset conditions, and the change value of the gas-sensitive resistor; and perform a corresponding correction operation on the gas sensor based on the gas-sensitive resistor drift.

[0026] Preferably, the control device includes: a first determining module, configured to determine the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and a second determining module, configured to determine the change value of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0027] Preferably, determining the gas-sensitive resistor drift of the gas sensor under the operating conditions includes: based on the gas-sensitive resistor R of the gas sensor under the operating conditions. H The gas sensor, under the preset conditions, uses the gas-sensitive resistor R1, the change value of the gas-sensitive resistor ΔR1, and the following formula to determine the drift amount ΔR of the gas-sensitive resistor. H , Where a and b are the first constant and the second constant, respectively.

[0028] Preferably, performing the corresponding calibration operation on the gas sensor includes: calibrating the gas sensor according to the gas resistor drift when the gas resistor drift is less than or equal to a threshold; or sending fault information when the gas resistor drift is greater than the threshold.

[0029] Preferably, the calibration system further includes: a calibration device for calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; a first determining device for determining the functional relationship between the gas-sensitive resistor and the variable parameters; and a second determining device for determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0030] Preferably, the preset conditions also include preset humidity.

[0031] For specific details and benefits of the aging drift correction system for gas sensors provided in the embodiments of the present invention, please refer to the above description of the aging drift correction method for gas sensors, which will not be repeated here.

[0032] A fifth aspect of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements a method for correcting reversible drift of a gas sensor and / or a method for correcting aging drift of a gas sensor.

[0033] A sixth aspect of the present invention provides a chip for executing a computer program, which, when executed by the chip, implements a method for correcting reversible drift of the gas sensor and / or a method for correcting aging drift of the gas sensor.

[0034] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0035] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0036] Figure 1 This is a schematic diagram of a method for correcting the reversible drift of a gas sensor according to an embodiment of the present invention;

[0037] Figure 2 This is a structural diagram of a long-term drift correction system for a gas sensor provided in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the correction process for reversible drift of a MEMS gas sensor provided in an embodiment of the present invention;

[0039] Figure 4 This is a flowchart of a method for correcting aging drift of a gas sensor according to an embodiment of the present invention; and

[0040] Figure 5 This is a schematic diagram of the correction process for long-term aging drift of a gas sensor provided in an embodiment of the present invention. Detailed Implementation

[0041] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0042] After long-term storage, the resistance of a gas sensor will experience reversible drift, which is related to the storage environment. To address this drift, the gas sensor can undergo a restorative aging process upon its initial power-on at the application site.

[0043] Figure 1 This is a schematic diagram of a method for correcting reversible drift of a gas sensor according to an embodiment of the present invention. Figure 1As shown, the calibration method may include: step S101, stopping heating the gas sensor after heating it to a first preset temperature; step S102, measuring the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature and the second preset temperature being lower than the first preset temperature; step S103, determining the rate of change of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the gas-sensitive resistor used to calibrate the gas sensor under the preset conditions; and step S104, performing a corresponding calibration operation on the gas sensor based on the rate of change of the gas-sensitive resistor.

[0044] The following is an explanation and description of the specific content of steps S101-S104 above.

[0045] Step S101: After heating the gas sensor to a first preset temperature and maintaining it for a preset time, stop heating the gas sensor.

[0046] The gas sensor can be an electrochemical gas sensor, or more specifically, a MEMS (Micro-Electromechanical System) sensor.

[0047] Specifically, the MEMS gas sensor 5 is heated by the heating module 8 to reach a preset temperature (this heating process can restore the activity of the gas-sensitive material of the MEMS gas sensor), and the heating is maintained for a time T1 before the heating module 8 is turned off. Figure 2 As shown.

[0048] Step S102: Measure the voltage of the matching resistor of the gas sensor under preset conditions.

[0049] The preset conditions include a second preset temperature, and the second preset temperature being lower than the first preset temperature. Specifically, the first preset temperature and the second preset temperature can be reasonably set according to actual conditions. For example, the second preset temperature can be room temperature or ambient temperature.

[0050] Specifically, after heating for time T1, heating module 8 is turned off, and time T2 is waited for the MEMS gas sensor to cool to room temperature. In the unheated state (e.g., room temperature), the MEMS gas sensor does not react to the sensitive gas; at this time, the matching resistance R is measured. L voltage V t ,like Figure 2 As shown.

[0051] Step S103: Determine the rate of change of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor.

[0052] Wherein, the calibrated gas-sensitive resistor is the gas-sensitive resistor calibration value of the gas sensor under the preset conditions.

[0053] Specifically, in one embodiment, the gas-sensitive resistor is calibrated at room temperature during factory manufacturing to obtain the calibrated gas-sensitive resistor R. o .

[0054] In another embodiment, the calibration method further includes: calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; determining the functional relationship between the gas-sensitive resistor and the variable parameters; and determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0055] Among these, the variable parameter in the different conditions can be temperature.

[0056] Gas-sensitive resistor R is tested at the factory. o During calibration, R can be... o Data at different temperatures T were individually calibrated, and the corresponding relationships were fitted to a formula:

[0057] R o (T)=aT 2 +bT+c, Equation 1

[0058] Where a, b, and c are all fitting coefficients.

[0059] Then, by substituting the ambient temperature into Equation 1 above, the calibrated gas-sensitive resistor at the ambient temperature can be obtained.

[0060] For step S103, determining the rate of change of the gas-sensitive resistor includes: determining the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and determining the rate of change of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0061] The matching resistor is connected in series with the gas sensor (i.e., gas-sensitive resistor).

[0062] Specifically, firstly, using the matching resistor R L Based on the principle of resistive voltage division of the power supply voltage V by the gas-sensitive resistor R1, the gas-sensitive resistor R1 of the MEMS gas sensor in the unheated state (e.g., room temperature) is calculated using the following formula:

[0063]

[0064] Among them, V t To match resistor R L The voltage.

[0065] Then, the calculated gas-sensitive resistor R1 is compared with the calibrated gas-sensitive resistor R1 under the factory setting in an unheated state (e.g., room temperature). o By comparison, the rate of change β of the gas-sensitive resistor at this time is calculated:

[0066]

[0067] Step S104: Perform a corresponding calibration operation on the gas sensor based on the change rate of the gas-sensitive resistor.

[0068] For step S104, performing the corresponding calibration operation on the gas sensor may include: determining that the reversible drift has disappeared when the rate of change of the gas resistivity is less than or equal to a preset value; or heating the gas sensor to the first preset temperature and maintaining it for the preset time when the rate of change of the gas resistivity is greater than the preset value and repeating the calibration method (e.g., steps S101-S104).

[0069] If the rate of change of the gas-sensitive resistor β in the unheated state (e.g., room temperature) of the MEMS gas sensor is ≤ A%, then it is determined that the long-term reversible drift has disappeared, and then it enters the normal detection mode (detecting gas concentration). If the rate of change β > A%, then it is determined that the long-term reversible drift still exists, and the above steps (e.g., steps S101-S104) are repeated until the reversible drift of the MEMS gas sensor disappears.

[0070] In one embodiment, in addition to the second preset temperature, the preset conditions may also include a preset humidity. The second preset temperature may be the ambient temperature, and the preset humidity may be the ambient humidity. Accordingly, in determining the calibration gas-sensitive resistor, the variable parameters in the different conditions include temperature and humidity.

[0071] Accordingly, after heating the gas sensor to a first preset temperature, heating of the gas sensor is stopped and the resistance value of the matching resistor of the gas sensor is measured at the ambient temperature and ambient humidity. Then, the rate of change of the gas-sensitive resistor is determined based on the power supply voltage, the voltage of the matching resistor at the ambient temperature and ambient humidity, and the calibrated gas-sensitive resistor. Next, a corresponding calibration operation is performed on the gas sensor based on the rate of change of the gas-sensitive resistor.

[0072] Specifically, the MEMS gas sensor 5 is heated by the heating module 8 to reach a preset temperature. After power-on for time T1, the heating module is turned off, and time T2 is waited for the MEMS gas sensor to cool down to the ambient temperature. Under the ambient temperature and humidity, the MEMS gas sensor does not react with the sensitive gas. At this time, the matching resistance R is measured. L voltage V t Then, the gas-sensitive resistor R1 of the MEMS gas sensor under the field temperature and humidity conditions is calculated using Formula 2.

[0073] Since the gas sensor's gas-sensitive resistor is also affected by changes in humidity in the external environment, the temperature and humidity environment at the application site will differ from the factory-calibrated gas-sensitive resistor R. o The situation may differ at different times. Therefore, the gas-sensitive resistor R is tested at the factory. o During calibration, R o Data at different temperatures (T) and humidity (%RH) were individually calibrated, and the corresponding relationships were fitted into formulas. For example, a second-order polynomial formula can be fitted, as shown below:

[0074] R o (T, %RH) = mT 2 +lT+n(%RH)*T+p(%RH)+q(%RH) 2 +w, Equation 4

[0075] Where m, l, n, p, q, and w are all fitting coefficients.

[0076] Then, substituting the ambient temperature and humidity into Equation 4 above, we can obtain the calibrated gas-sensitive resistor under the ambient temperature and humidity conditions. Next, we will use R in Equation 3... o By replacing Equation 4 with the corrected temperature and humidity data, the rate of change of the gas-sensitive resistor β can be calculated, and corresponding correction operations can be performed based on the rate of change of the gas-sensitive resistor β. Therefore, this embodiment can eliminate the influence of temperature and humidity factors, thereby further enhancing the accuracy of judging the restorative aging state.

[0077] Specifically, now Figure 2 The following example illustrates the correction process for reversible drift in a MEMS gas sensor. Figure 3 As shown.

[0078] like Figure 3 As shown, the process for correcting the reversible drift of a MEMS gas sensor may include the following steps S301-S309.

[0079] Step S301: The host computer issues a restorative aging command.

[0080] When the system is powered on for the first time, the host computer 1 (e.g., the data acquisition host computer) sends a recovery aging command to the controller 3 (e.g., the microcontroller unit MCU) through the communication interface 2.

[0081] Step S302: Control the heating module to turn on.

[0082] After receiving the command, the controller 3 (e.g., microcontroller unit MCU) powers on the MEMS gas sensor 5 and controls the heating module 8 to heat the MEMS gas sensor 5 through the heating control module 4.

[0083] Step S303: Determine if the heating time has reached T1. If yes, proceed to step S304; otherwise, proceed to step S302.

[0084] Step S304: Control the heating module to shut down.

[0085] After power-on time T1, heating module 8 is turned off via heating control module 4.

[0086] Step S305, wait for time T2.

[0087] Wait for time T2 to allow the MEMS gas sensor 5 to cool to the ambient temperature. At the ambient temperature, the MEMS gas sensor 5 does not react with the sensitive gas.

[0088] Step S306: Measure the voltage of the matching resistor at the field temperature and calculate the gas-sensitive resistor of the MEMS gas sensor at the field temperature.

[0089] Controller 3 (e.g., microcontroller unit MCU) measures the matching resistor R via ADC conversion module 6. L voltage V t And calculate the gas-sensitive resistor R1 at the field temperature according to Equation 2.

[0090] Step S307: Calculate the rate of change β of the gas-sensitive resistor.

[0091] Temperature information (i.e., ambient temperature) is collected by temperature and humidity sensor 7; controller 3 (e.g., microcontroller unit MCU) acquires the ambient temperature and, in conjunction with the functional relationship between the gas-sensitive resistor and temperature calibrated at the factory (Equation 1), determines the calibrated gas-sensitive resistor R. o Then, based on R1 and R... o Equation 3 can be used to calculate the rate of change β of the gas-sensitive resistor.

[0092] Step S308: Determine if β ≤ A%. If yes, proceed to step S309; ​​otherwise, proceed to step S302.

[0093] Step S309: Confirm completion of restorative aging.

[0094] In other words, the process of correcting reversible drift caused by long-term storage is completed.

[0095] Upon initial power-up, the host computer sends a restorative aging command to the controller. The controller then directs the MEMS gas sensor to undergo restorative heating aging, stopping the heating process after a specified period. Utilizing the characteristic that the MEMS gas sensor does not react with the detected gas when unheated, the resistance of the gas-sensitive resistor in the unheated state is measured and compared with the factory-calibrated resistance value in the unheated state. The rate of change in resistance determines whether restorative heating aging is complete. This scheme enables remote, automatic restorative heating aging of the gas sensor in complex gas environments at the application site, eliminating interference from reversible drift caused by long-term storage of the gas sensor on the detection data.

[0096] In summary, this invention creatively firstly heats the gas sensor to a first preset temperature and maintains it for a preset time, then stops heating the gas sensor; secondly, it measures the voltage of the matching resistor of the gas sensor under preset conditions; next, it determines the rate of change of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor; finally, it performs a corresponding calibration operation on the gas sensor based on the rate of change of the gas-sensitive resistor. This invention can perform long-term reversible drift correction of gas sensors in complex gas environments at the application site.

[0097] In practical applications, gas sensors (e.g., MEMS gas sensors) experience aging after prolonged use, leading to long-term, irreversible drift that requires recalibration. For gas sensors already in use or that cannot be disassembled, the concentration of the detected gas may remain unknown at the application site. To address this issue, this invention employs a remote automatic calibration method.

[0098] Figure 4 This is a flowchart of a method for correcting aging drift of a gas sensor according to an embodiment of the present invention. Figure 4As shown, the calibration method may include: step S401, obtaining the gas-sensitive resistor of the gas sensor under operating conditions, wherein the operating conditions include a first preset temperature; step S402, measuring the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature, and the second preset temperature is less than the first preset temperature; step S403, determining the change value of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the gas-sensitive resistor used to calibrate the gas sensor under the preset conditions; step S404, determining the gas-sensitive resistor drift of the gas sensor under operating conditions based on the gas-sensitive resistor of the gas sensor under operating conditions, the gas-sensitive resistor of the gas sensor under the preset conditions, and the change value of the gas-sensitive resistor; and step S405, performing a corresponding calibration operation on the gas sensor based on the gas-sensitive resistor drift.

[0099] The following sections will explain and illustrate the specific content of steps S401-S405.

[0100] Step S401: Obtain the gas-sensitive resistor of the gas sensor under operating conditions.

[0101] The operating conditions include a first preset temperature. At the first preset temperature, the gas sensor can react with the corresponding sensitive gas, causing a change in the gas-sensitive resistance of the gas sensor. The gas concentration of the sensitive gas can be calculated by combining the first preset temperature.

[0102] The gas sensor can be an electrochemical gas sensor, or more specifically, a MEMS (Micro-Electromechanical System) sensor.

[0103] On the one hand, the gas-sensitive resistor of the gas sensor under operating conditions, which was previously measured, can be used.

[0104] On the other hand, obtaining the gas-sensitive resistor of the gas sensor under operating conditions includes: determining the gas-sensitive resistor of the gas sensor under operating conditions based on the power supply voltage, the resistance value of the matching resistor of the gas sensor, and the voltage of the matching resistor under operating conditions.

[0105] Before performing the step of measuring the voltage of the matching resistor of the gas sensor under preset conditions (i.e., step S402), the calibration method further includes stopping the heating of the gas sensor.

[0106] Specifically, the voltage V of the matching resistor at the first preset temperature is measured.H Then, the gas resistance R of the MEMS gas sensor at the first preset temperature is calculated using the following formula. H ,

[0107]

[0108] Where V is the power supply voltage.

[0109] Step S402: Measure the voltage of the matching resistor of the gas sensor under preset conditions.

[0110] The preset conditions include a second preset temperature, and the second preset temperature being lower than the first preset temperature. Specifically, the first preset temperature and the second preset temperature can be reasonably set according to actual conditions. For example, the second preset temperature can be room temperature or ambient temperature.

[0111] Specifically, the heating module is turned off, and time T2 is waited for the MEMS gas sensor to cool to room temperature. In the unheated state (e.g., room temperature), the MEMS gas sensor does not react to the sensitive gas; at this time, the matching resistance R is measured. L voltage V t .

[0112] Step S403: Determine the change value of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor.

[0113] Wherein, the calibrated gas-sensitive resistor is the gas-sensitive resistor calibration value of the gas sensor under the preset conditions.

[0114] Specifically, in one embodiment, the gas-sensitive resistor is calibrated at room temperature during factory manufacturing to obtain the calibrated gas-sensitive resistor R. o .

[0115] In another embodiment, the calibration method further includes: calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; determining the functional relationship between the gas-sensitive resistor and the variable parameters; and determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0116] The variable parameter in the different conditions can be temperature. For the calibration method of the gas-sensitive resistor, please refer to the relevant description in step S102 above, which will not be repeated here.

[0117] For step S403, determining the change value of the gas-sensitive resistor includes: determining the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and determining the change value of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0118] The matching resistor is connected in series with the gas sensor (i.e., gas-sensitive resistor).

[0119] Specifically, firstly, using the matching resistor R L Based on the principle of resistive voltage division of the power supply voltage V by the gas-sensitive resistor R1, the gas-sensitive resistor R1 of the MEMS gas sensor in the unheated state (e.g., room temperature) is calculated according to Equation 2 above. Then, the calculated gas-sensitive resistor R1 is compared with the factory-calibrated gas-sensitive resistor R1 in the unheated state (e.g., room temperature). o The difference, i.e., ΔR1 = R1 - R o .

[0120] Step S404: Determine the gas sensor's gas sensor's gas sensor's gas sensor drift amount under the operating conditions based on the gas sensor's gas sensor resistance under the operating conditions, the gas sensor's gas sensor resistance under the preset conditions, and the gas sensor resistance change value.

[0121] For step S404, determining the gas-sensitive resistor drift of the gas sensor under the operating conditions includes: based on the gas-sensitive resistor R of the gas sensor under the operating conditions. H The gas sensor, under the preset conditions, uses the gas-sensitive resistor R1, the change value of the gas-sensitive resistor ΔR1, and the following formula to determine the drift amount ΔR of the gas-sensitive resistor. H ,

[0122]

[0123] Where a and b are the first constant and the second constant, respectively. The specific values ​​of a and b are related to the gas that the gas sensor is sensitive to.

[0124] Step S405: Perform a corresponding calibration operation on the gas sensor based on the drift of the gas-sensitive resistor.

[0125] For step S405, performing the corresponding calibration operation on the gas sensor includes: calibrating the gas sensor according to the gas resistor drift when the gas resistor drift is less than or equal to a threshold; or sending fault information when the gas resistor drift is greater than the threshold.

[0126] Specifically, if the gas-sensitive resistor drift ΔR H If the value is less than or equal to the safety threshold, then ΔR is used. H The concentration detection formula of the gas sensor is calibrated.

[0127] For example, if the concentration detection formula is P = f(R, T), where R is the gas-sensitive resistor of the gas sensor at temperature T, then the drift amount is used to correct the gas-sensitive resistor R, resulting in the following corrected formula: P = f(R + ΔR) H ,T).

[0128] For example, if the concentration detection formula is P = f(R, T, %RH), where R is the gas-sensitive resistor of the gas sensor at %RH under temperature T and humidity, then the drift amount is used to correct the gas-sensitive resistor R, resulting in the following corrected formula: P = f(R + ΔR) H (T,%RH).

[0129] If the gas-sensitive resistor drift ΔR H If the value exceeds the safety threshold, the gas sensor is determined to need to be replaced. The fault information is then sent to the host computer via the communication module to remind the operator to replace it.

[0130] In one embodiment, in addition to the second preset temperature, the preset conditions may also include a preset humidity. The second preset temperature may be the ambient temperature, and the preset humidity may be the ambient humidity. Accordingly, in determining the calibration gas-sensitive resistor, the variable parameters in the different conditions include temperature and humidity.

[0131] Accordingly, based on the power supply, the resistance value of the matching resistor of the gas sensor, and the voltage of the matching resistor under the operating conditions, the gas-sensitive resistor of the gas sensor under the operating conditions is determined; heating of the gas sensor is stopped, and the voltage of the matching resistor of the gas sensor under the ambient temperature and humidity is measured; then, based on the power supply voltage, the voltage of the matching resistor under the ambient temperature and humidity, and the calibrated gas-sensitive resistor, the change value of the gas-sensitive resistor is determined; next, based on the gas-sensitive resistor of the gas sensor under the operating conditions, the gas-sensitive resistor of the gas sensor under preset conditions, and the change value of the gas-sensitive resistor, the gas-sensitive resistor drift of the gas sensor under the operating conditions is determined; finally, based on the gas-sensitive resistor drift, a corresponding calibration operation is performed on the gas sensor.

[0132] Specifically, the voltage V across the matching resistor under operating conditions is measured. H The gas-sensitive resistor R of the MEMS gas sensor under operating conditions is calculated according to Equation 5. HTurn off the heating module and wait for time T2 to allow the MEMS gas sensor to cool to the ambient temperature. At the ambient temperature and humidity, the MEMS gas sensor will not react to the sensitive gas. At this time, measure the matching resistance R. L voltage V t Then, the gas-sensitive resistor R1 of the MEMS gas sensor under the field temperature and humidity conditions is calculated using Formula 2.

[0133] Since the gas sensor's gas-sensitive resistor is also affected by changes in humidity in the external environment, the temperature and humidity environment at the application site will differ from the factory-calibrated gas-sensitive resistor R. o The situation may differ at different times. Therefore, the gas-sensitive resistor R is tested at the factory. o During calibration, R o Data at different temperatures (T) and humidity (%RH) were individually calibrated, and the corresponding relationships were fitted into formulas. For example, a second-order polynomial formula (Equation 4) could be fitted. Then, substituting the on-site temperature and humidity into Equation 4, the calibrated gas-sensitive resistor R under the on-site temperature and humidity conditions could be obtained. o Next, the change in the gas-sensitive resistor value ΔR1 = R1 - R was calculated. o And based on the changes in the gas-sensitive resistor values ​​ΔR1 and R H The drift ΔR of the gas-sensitive resistor can be calculated using R1 and Equation 6 above. H Finally, based on the gas-sensitive resistor drift ΔR... H The gas sensor is then subjected to corresponding calibration operations. Therefore, this embodiment eliminates the influence of temperature and humidity factors, thereby further enhancing the accuracy of determining long-term aging drift (irreversible drift).

[0134] Specifically, now Figure 2 The calibration system shown is used as an example to illustrate the calibration process for long-term aging drift of a MEMS gas sensor. Figure 5 As shown.

[0135] like Figure 5 As shown, the correction process for long-term aging drift of MEMS gas sensors may include the following steps S501-S511.

[0136] Step S501: The host computer issues a long-term zero-point drift correction command.

[0137] The host computer 1 (e.g., a data acquisition host computer) sends a zero-point long-term drift correction command to the controller 3 (e.g., a microcontroller unit MCU) through the communication interface 2.

[0138] Step S502: Measure the voltage across the matching resistor under operating conditions and calculate the gas-sensitive resistor R of the MEMS gas sensor under operating conditions. H .

[0139] After receiving the command, controller 3 (e.g., microcontroller unit MCU) measures the matching resistor R through ADC conversion module 6. L Voltage V under operating conditions H And calculate the gas-sensitive resistor R under the working conditions according to Equation 5. H .

[0140] Step S503: Control the heating module to shut down.

[0141] Step S504, wait for time T2.

[0142] Wait for time T2 to allow the MEMS gas sensor 5 to cool to the ambient temperature. At the ambient temperature, the MEMS gas sensor 5 does not react with the sensitive gas.

[0143] Step S505: Measure the voltage of the matching resistor at the field temperature and calculate the gas-sensitive resistor R1 of the MEMS gas sensor at the field temperature.

[0144] Controller 3 (e.g., microcontroller unit MCU) measures the matching resistor R via ADC conversion module 6. L voltage V t And calculate the gas-sensitive resistor R1 at the field temperature according to Equation 2.

[0145] Step S506: Calculate the change value ΔR1 of the gas-sensitive resistor.

[0146] Temperature information (i.e., ambient temperature) is collected by temperature and humidity sensor 7; controller 3 (e.g., microcontroller unit MCU) acquires the ambient temperature and, in conjunction with the functional relationship between the gas-sensitive resistor and temperature calibrated at the factory (Equation 1), determines the calibrated gas-sensitive resistor R. o Then, based on R1 and R... o The change in the gas-sensitive resistor value ΔR1 can be calculated.

[0147] Step S507, based on △R1, R1, R H Calculate the drift ΔR of the gas-sensitive resistor H .

[0148] Controller 3 (e.g., microcontroller unit MCU) will input ΔR1, R1, R... H Substituting into Formula 6, the drift ΔR of the gas-sensitive resistor is calculated. H .

[0149] Step S508, determine △R H Is it within the safety threshold? If yes, proceed to step S509; otherwise, proceed to step S511.

[0150] Step S509, use △R HThe concentration detection formula of the MEMS gas sensor is calibrated.

[0151] Step S510: Confirm that long-term aging drift correction has been completed.

[0152] In other words, the correction process for irreversible drift caused by long-term aging is completed.

[0153] Step S511: Send fault information to the host computer.

[0154] Send the fault information to host computer 1 (e.g., data acquisition host computer).

[0155] The above embodiments utilize the characteristic that MEMS gas sensors do not react with the detected gas when not heated. First, the gas-sensitive resistor R of the MEMS gas sensor under normal operating conditions is measured. H Then turn off the heating module, measure the gas-sensitive resistor R1 in the non-heating state, and calculate the difference between R1 and the factory-calibrated gas-sensitive resistor R1 in the non-heating state. o The difference ΔR1 is used to calculate the zero-point drift ΔR of the MEMS gas sensor under normal operating conditions using the correction formula. H This invention enables remote long-term zero-point aging and drift correction of MEMS gas sensors in complex gas environments at the application site, solving the problem of long-term zero-point aging and drift correction for gas sensors that are already in use at the application site or cannot be disassembled and removed.

[0156] In summary, this invention creatively obtains the gas-sensitive resistor of the gas sensor under operating conditions; secondly, it stops heating the gas sensor and measures the voltage of the matching resistor of the gas sensor under preset conditions; next, it determines the change value of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor; then, it determines the gas-sensitive resistor drift amount under operating conditions based on the gas-sensitive resistor of the gas sensor under operating conditions, the gas-sensitive resistor of the gas sensor under the preset conditions, and the change value of the gas-sensitive resistor; finally, it performs a corresponding calibration operation on the gas sensor based on the gas-sensitive resistor drift amount. This invention can perform long-term aging drift calibration of gas sensors in complex gas environments at the application site.

[0157] An embodiment of the present invention provides a correction system for reversible drift of a gas sensor. The correction system includes: a heating device for stopping heating the gas sensor after heating it to a first preset temperature and maintaining it for a preset time; a voltage measuring device for measuring the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature and the second preset temperature is less than the first preset temperature; and a control device for performing the following operations: determining the rate of change of a gas-sensitive resistor based on a power supply voltage, the voltage of the matching resistor under the preset conditions, and a calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the calibrated value of the gas sensor under the preset conditions; and performing a corresponding correction operation on the gas sensor based on the rate of change of the gas-sensitive resistor.

[0158] Preferably, the control device includes: a first determining module, configured to determine the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and a second determining module, configured to determine the gas-sensitive resistor change rate based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0159] Preferably, the corresponding calibration operation on the gas sensor includes: determining that the reversible drift has disappeared when the rate of change of the gas resistivity is less than or equal to a preset value; or controlling the heating device to heat the gas sensor to the first preset temperature and maintain it for the preset time when the rate of change of the gas resistivity is greater than the preset value, and repeating the calibration process through the calibration system.

[0160] Preferably, the calibration system further includes: a calibration device for calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; a first determining device for determining the functional relationship between the gas-sensitive resistor and the variable parameters; and a second determining device for determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0161] Preferably, the preset conditions also include preset humidity.

[0162] The control device may be: Figure 2 The controller 3 in the middle; the heating device can be a Figure 2 The heating module 8 in the middle; and the voltage measuring device can be used for Figure 2 The ADC conversion module 6 in the middle.

[0163] For specific details and benefits of the gas sensor reversible drift correction system provided in the embodiments of the present invention, please refer to the above description of the gas sensor reversible drift correction method, which will not be repeated here.

[0164] An embodiment of the present invention provides a correction system for aging drift of a gas sensor. The correction system includes: a control device for acquiring the gas-sensitive resistor of the gas sensor under operating conditions, wherein the operating conditions include a first preset temperature; a heating device for stopping heating of the gas sensor; and a voltage measuring device for measuring the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature, and the second preset temperature is lower than the first preset temperature. The control device is further configured to perform the following operations: determine the change value of the gas-sensitive resistor based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor, wherein the calibrated gas-sensitive resistor is the calibrated value of the gas-sensitive resistor of the gas sensor under the preset conditions; determine the gas-sensitive resistor drift of the gas sensor under operating conditions based on the gas-sensitive resistor of the gas sensor under the operating conditions, the gas-sensitive resistor of the gas sensor under the preset conditions, and the change value of the gas-sensitive resistor; and perform a corresponding correction operation on the gas sensor based on the gas-sensitive resistor drift.

[0165] Preferably, the control device includes: a first determining module, configured to determine the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and a second determining module, configured to determine the change value of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

[0166] Preferably, determining the gas-sensitive resistor drift of the gas sensor under the operating conditions includes: based on the gas-sensitive resistor R of the gas sensor under the operating conditions. H The gas sensor, under the preset conditions, uses the gas-sensitive resistor R1, the change value of the gas-sensitive resistor ΔR1, and the following formula to determine the drift amount ΔR of the gas-sensitive resistor. H , Where a and b are the first constant and the second constant, respectively.

[0167] Preferably, performing the corresponding calibration operation on the gas sensor includes: calibrating the gas sensor according to the gas resistor drift when the gas resistor drift is less than or equal to a threshold; or sending fault information when the gas resistor drift is greater than the threshold.

[0168] Preferably, the calibration system further includes: a calibration device for calibrating the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters in the different conditions are the same as the parameters in the preset conditions; a first determining device for determining the functional relationship between the gas-sensitive resistor and the variable parameters; and a second determining device for determining the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

[0169] Preferably, the preset conditions also include preset humidity.

[0170] Preferably, the control device for obtaining the gas-sensitive resistor of the gas sensor under operating conditions includes: determining the gas-sensitive resistor of the gas sensor under operating conditions based on the power supply voltage, the resistance value of the matching resistor of the gas sensor, and the voltage of the matching resistor under operating conditions; the calibration system further includes: a heating device for stopping heating of the gas sensor.

[0171] The control device may be: Figure 2 The controller 3 in the middle; the heating device can be a Figure 2 The heating module 8 in the middle; and the voltage measuring device can be used for Figure 2 The ADC conversion module 6 in the middle.

[0172] For specific details and benefits of the aging drift correction system for gas sensors provided in the embodiments of the present invention, please refer to the above description of the aging drift correction method for gas sensors, which will not be repeated here.

[0173] After long-term drift correction of the gas sensor (such as MEMS gas sensor 5) using any one or two correction methods, the corrected gas sensor (such as MEMS gas sensor 5) can be used to measure the gas concentration in the field environment.

[0174] Specifically, controller 3 heats the heating module inside the MEMS gas sensor 5 chip via heating control module 4. After heating for a certain period, the gas sensor reaches its operating temperature, at which point the chip inside the MEMS gas sensor 5 reacts with the gas to be detected. Under different gas concentrations, the gas-sensitive resistor inside the MEMS gas sensor 5 varies, causing a change in the voltage of the external matching resistor. Controller 3 acquires the voltage of the matching resistor via ADC conversion module 6 and collects temperature and humidity information from the environment via temperature and humidity sensor 7, combining this information with formulas calibrated before factory shipment (e.g., P = f(R, T), P = f(R + ΔR)). H ,T) or P=f(R+△R H The current gas concentration data is calculated using the formula ,T,%RH).

[0175] An embodiment of the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements a method for correcting reversible drift of a gas sensor and / or a method for correcting aging drift of a gas sensor.

[0176] One embodiment of the present invention provides a chip for executing a computer program, which, when executed by the chip, implements a method for correcting reversible drift of a gas sensor and / or a method for correcting aging drift of the gas sensor.

[0177] Specifically, this embodiment provides a chip, including: a processor; a memory for storing a computer program executed by the processor; the processor is configured to read the computer program from the memory and execute the computer program to implement the method for correcting reversible drift of the gas sensor and / or the method for correcting aging drift of the gas sensor.

[0178] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0179] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0180] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0181] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for correcting reversible drift of a gas sensor, wherein the gas sensor is a microelectromechanical system (MEMS) sensor, characterized in that, The correction method includes: After heating the gas sensor to a first preset temperature and maintaining it for a preset time, the heating of the gas sensor is stopped, wherein the heating can restore the activity of the gas-sensitive material of the gas sensor; Measure the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature and the second preset temperature being less than the first preset temperature, wherein the second preset temperature is room temperature or ambient temperature; The rate of change of the gas-sensitive resistor is determined based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor. The calibrated gas-sensitive resistor is the calibrated value of the gas sensor under the preset conditions. The gas-sensitive resistor R is calibrated at the factory. o During calibration, R o Data at different temperatures T were calibrated one by one, and the corresponding relationships were fitted into a formula. Substituting the field temperature into this formula, the calibrated gas-sensitive resistor at the field temperature was obtained; and Based on the rate of change of the gas resistivity, a corresponding calibration operation is performed on the gas sensor. The matching resistor is connected in series with the gas-sensitive resistor. The step of performing the corresponding calibration operation on the gas sensor includes: determining that the reversible drift has disappeared when the rate of change of the gas resistivity is less than or equal to a preset value; or heating the gas sensor to the first preset temperature and maintaining it for the preset time when the rate of change of the gas resistivity is greater than the preset value, and repeating the calibration method.

2. The correction method according to claim 1, characterized in that, The determination of the gas-sensitive resistor change rate includes: Based on the power supply voltage, the voltage across the matching resistor under the preset conditions, and the resistance value of the matching resistor, the gas-sensitive resistor of the gas sensor under the preset conditions is determined; and The rate of change of the gas-sensitive resistor is determined based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

3. The correction method according to claim 1, characterized in that, The correction method further includes: The gas sensor is calibrated under different conditions, wherein the variable parameters under the different conditions include temperature; Determine the functional relationship between the gas-sensitive resistor and the variable parameters; and The calibration gas-sensitive resistor is determined based on the functional relationship and the preset conditions.

4. The correction method according to any one of claims 1-3, characterized in that, The preset conditions also include preset humidity.

5. A method for correcting aging drift in a gas sensor, wherein the gas sensor is a microelectromechanical system (MEMS) sensor, characterized in that, The correction method includes: Obtain the gas-sensitive resistor of the gas sensor under operating conditions, wherein the operating conditions include a first preset temperature; Measure the voltage of the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature and the second preset temperature being less than the first preset temperature, wherein the second preset temperature is room temperature or ambient temperature; The change value of the gas-sensitive resistor is determined based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor. The calibrated gas-sensitive resistor is the calibrated value of the gas sensor under the preset conditions. The gas-sensitive resistor R is calibrated at the factory. o During calibration, R o The data at different temperatures T were calibrated one by one, and the corresponding relationship was fitted into a formula. The field temperature was substituted into the formula to obtain the calibrated gas-sensitive resistor at the field temperature. Based on the gas sensor's resistance under the operating conditions, the gas sensor's resistance under the preset conditions, and the change in the gas sensor's resistance value, determine the gas sensor's resistance drift under the operating conditions; and Based on the drift of the gas-sensitive resistor, a corresponding calibration operation is performed on the gas sensor. The matching resistor is connected in series with the gas-sensitive resistor. The step of performing corresponding calibration operations on the gas sensor includes: calibrating the gas sensor based on the gas resistor drift when the gas resistor drift is less than or equal to a threshold; or sending fault information when the gas resistor drift is greater than the threshold. The step of determining the gas-sensitive resistor drift of the gas sensor under the operating conditions includes: based on the gas-sensitive resistor of the gas sensor under the operating conditions. R H The gas sensor's gas-sensitive resistor under the preset conditions R 1. The change value Δ of the gas-sensitive resistor R 1. The drift amount Δ of the gas-sensitive resistor is determined using the following formula. R H , ， in, a , b These are the first constant and the second constant, respectively.

6. The correction method according to claim 5, characterized in that, Determining the change value of the gas-sensitive resistor includes: Based on the power supply voltage, the voltage across the matching resistor under the preset conditions, and the resistance value of the matching resistor, the gas-sensitive resistor of the gas sensor under the preset conditions is determined; and The change value of the gas-sensitive resistor is determined based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

7. The correction method according to claim 5, characterized in that, The correction method further includes: The gas sensor is calibrated under different conditions, wherein the variable parameters under the different conditions include temperature; Determine the functional relationship between the gas-sensitive resistor and the variable parameters; and The calibration gas-sensitive resistor is determined based on the functional relationship and the preset conditions.

8. The correction method according to any one of claims 5-7, characterized in that, The preset conditions also include preset humidity.

9. The correction method according to any one of claims 5-7, characterized in that, The process of obtaining the gas-sensitive resistor of the gas sensor under operating conditions includes: Based on the power supply voltage, the resistance value of the matching resistor of the gas sensor, and the voltage across the matching resistor under the operating conditions, determine the gas-sensitive resistor of the gas sensor under the operating conditions. Before performing the step of measuring the voltage of the matching resistor of the gas sensor under preset conditions, the calibration method further includes: stopping heating the gas sensor.

10. A correction system for reversible drift of a gas sensor, wherein the gas sensor is a microelectromechanical system (MEMS) sensor, characterized in that, The correction system includes: A heating device is used to stop heating the gas sensor after heating it to a first preset temperature and maintaining it for a preset time, wherein the heating can restore the activity of the gas-sensitive material of the gas sensor; A voltage measuring device is used to measure the voltage across the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature, and the second preset temperature being lower than a first preset temperature, wherein the second preset temperature is room temperature or ambient temperature; and Control device for performing the following operations: The rate of change of the gas-sensitive resistor is determined based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor. The calibrated gas-sensitive resistor is the calibrated value of the gas sensor under the preset conditions. The gas-sensitive resistor R is calibrated at the factory. o During calibration, R o Data at different temperatures T were calibrated one by one, and the corresponding relationships were fitted into a formula. Substituting the field temperature into this formula, the calibrated gas-sensitive resistor at the field temperature was obtained; and Based on the rate of change of the gas resistivity, a corresponding calibration operation is performed on the gas sensor. The matching resistor is connected in series with the gas-sensitive resistor. The calibration operation performed on the gas sensor includes: determining that the reversible drift has disappeared when the rate of change of the gas resistivity is less than or equal to a preset value; or controlling the heating device to heat the gas sensor to the first preset temperature and maintain it for the preset time when the rate of change of the gas resistivity is greater than the preset value, and repeating the calibration process through the calibration system.

11. The calibration system according to claim 10, characterized in that, The control device includes: The first determining module is configured to determine the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and The second determining module is used to determine the rate of change of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

12. The calibration system according to claim 10, characterized in that, The correction system also includes: A calibration device is used to calibrate the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters under the different conditions include temperature; A first determining device is used to determine the functional relationship between the gas-sensitive resistor and variable parameters; and The second determining device is used to determine the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

13. The calibration system according to any one of claims 10-12, characterized in that, The preset conditions also include preset humidity.

14. A system for correcting aging drift of a gas sensor, wherein the gas sensor is a microelectromechanical system (MEMS) sensor, characterized in that, The correction system includes: A control device is configured to acquire the gas-sensitive resistor value of the gas sensor under operating conditions, wherein the operating conditions include a first preset temperature; and A voltage measuring device is used to measure the voltage across the matching resistor of the gas sensor under preset conditions, wherein the preset conditions include a second preset temperature, and the second preset temperature being lower than a first preset temperature, wherein the second preset temperature is room temperature or ambient temperature. The control device is also used to perform the following operations: The change value of the gas-sensitive resistor is determined based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the calibrated gas-sensitive resistor. The calibrated gas-sensitive resistor is the calibrated value of the gas sensor under the preset conditions. The gas-sensitive resistor R is calibrated at the factory. o During calibration, R o The data at different temperatures T were calibrated one by one, and the corresponding relationship was fitted into a formula. The field temperature was substituted into the formula to obtain the calibrated gas-sensitive resistor at the field temperature. Based on the gas sensor's resistance under the operating conditions, the gas sensor's resistance under the preset conditions, and the change in the gas sensor's resistance value, determine the gas sensor's resistance drift under the operating conditions; and Based on the drift of the gas-sensitive resistor, a corresponding calibration operation is performed on the gas sensor. The matching resistor is connected in series with the gas-sensitive resistor. The step of performing corresponding calibration operations on the gas sensor includes: calibrating the gas sensor based on the gas resistor drift when the gas resistor drift is less than or equal to a threshold; or sending fault information when the gas resistor drift is greater than the threshold. The step of determining the gas-sensitive resistor drift of the gas sensor under the operating conditions includes: based on the gas-sensitive resistor of the gas sensor under the operating conditions. R H The gas sensor's gas-sensitive resistor under the preset conditions R 1. The change value Δ of the gas-sensitive resistor R 1. The drift amount Δ of the gas-sensitive resistor is determined using the following formula. R H , ， in, a , b These are the first constant and the second constant, respectively.

15. The calibration system according to claim 14, characterized in that, The control device includes: The first determining module is configured to determine the gas-sensitive resistor of the gas sensor under the preset conditions based on the power supply voltage, the voltage of the matching resistor under the preset conditions, and the resistance value of the matching resistor; and The second determining module is used to determine the change value of the gas-sensitive resistor based on the gas-sensitive resistor of the gas sensor under the preset conditions and the calibrated gas-sensitive resistor.

16. The calibration system according to any one of claims 14-15, characterized in that, The correction system also includes: A calibration device is used to calibrate the gas sensor's gas-sensitive resistor under different conditions, wherein the variable parameters under the different conditions include temperature; A first determining device is used to determine the functional relationship between the gas-sensitive resistor and variable parameters; and The second determining device is used to determine the calibrated gas-sensitive resistor based on the functional relationship and the preset conditions.

17. The calibration system according to any one of claims 14-15, characterized in that, The preset conditions also include preset humidity.

18. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method for correcting reversible drift of the gas sensor according to any one of claims 1-4 and / or the method for correcting aging drift of the gas sensor according to any one of claims 5-9.

19. A chip, characterized in that, The chip is used to execute a computer program that, when executed by the chip, implements a method for correcting reversible drift of the gas sensor according to any one of claims 1-4 and / or a method for correcting aging drift of the gas sensor according to any one of claims 5-9.

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