A humidity sensor calibration system and method for a portable temperature and humidity generator

Abstract

The application relates to the technical field of sensor calibration, in particular to a humidity sensor calibration system and method of a portable temperature and humidity generator, which comprises the following steps: recording a relative humidity display value and a humidity sensor output value of a preset calibration point, collecting the relative humidity display value, a temperature display value and the humidity sensor output value in each preset steady state period; analyzing the difference between the relative humidity display value and the humidity sensor output value, utilizing the correlation between the difference and the relative humidity display value and the temperature display value to obtain a coupling interference degree, then calculating an interference significance, and selecting high-quality calibration points in combination with a Grubbs test method; fitting the relative humidity display value and the humidity sensor output value based on the high-quality calibration points, so as to realize calibration of the humidity sensor. The application can improve the calibration precision of the sensor.

Description

Technical Field

[0001] This application relates to the field of sensor calibration technology, specifically to a humidity sensor calibration system and method for a portable temperature and humidity generator. Background Technology

[0002] During humidity sensor calibration, the humidity sensor is installed in a measurement chamber, and a portable temperature and humidity generator creates a suitable temperature and humidity environment within the chamber, thus providing a reliable environmental basis for humidity sensor calibration. Therefore, the portable temperature and humidity generator is of great value in terms of the practicality and reliability of humidity sensor calibration.

[0003] To perform on-site verification and calibration of humidity sensors, a portable temperature and humidity generator is typically used to create a temperature and humidity environment in a measurement room. The relative humidity display value and the humidity sensor output value are then collected at preset calibration points within this environment. The non-linear relationship between these two values ​​is used to calibrate the sensor's output error. However, because the coupling interference intensity of humidity sensor output values ​​at different preset calibration points varies significantly, current technologies directly calibrate humidity sensors using only the relative humidity display value and output value from these points. This approach fails to adequately consider the coupling interference characteristics of these different calibration points and to verify their quality. If any calibration points fail this verification, the resulting humidity sensor calibration accuracy will be poor, failing to meet the requirements for high-precision humidity sensors. Summary of the Invention

[0004] To address the aforementioned technical problems, the purpose of this application is to provide a humidity sensor calibration system and method for a portable temperature and humidity generator. The specific technical solution adopted is as follows: This application provides a method for calibrating the humidity sensor of a portable temperature and humidity generator, including the following steps: Read and record the relative humidity display value and humidity sensor output value at the preset calibration point, and simultaneously collect the relative humidity display value, temperature display value and humidity sensor output value in each preset steady-state cycle; The degree of difference between the relative humidity display value and the output value of the humidity sensor is analyzed, and the correlation between this degree of difference and the relative humidity display value and the temperature display value is used to obtain the coupling interference degree for each steady-state cycle. By analyzing the local discrete characteristics of the coupling interference degree in each steady-state cycle and the average distribution level of the coupling interference degree, the interference significance of each steady-state cycle is obtained. The Grubbs test is then used to verify the preset calibration points and select high-quality calibration points. The relative humidity display value is fitted to the humidity sensor output value based on the high-quality calibration point to achieve the calibration of the humidity sensor.

[0005] Preferably, during the process of the humidity rise in the room to be tested, each preset value corresponds to a preset calibration point. After reaching each preset calibration point, there is a steady-state period. After reaching the preset calibration point, the period of heat preservation and humidification before reading the final relative humidity display value is taken as a steady-state period.

[0006] Preferably, before obtaining the coupling interference degree of each steady-state cycle, the relative humidity display value, temperature display value and humidity sensor output value in each steady-state cycle are recorded as the steady-state relative humidity sequence, steady-state temperature sequence and steady-state humidity output value sequence of each steady-state cycle, and the difference sequence between the steady-state relative humidity sequence and the steady-state humidity output value sequence is recorded as the error fluctuation sequence.

[0007] Preferably, the formula for obtaining the coupling interference degree of each steady-state cycle is: In the formula, Let be the coupling disturbance degree in the t-th steady-state period. It is an exponential function with the natural constant as its base. and Let be the mean of all normalized instantaneous total frequencies of the humidity disturbance sequence and temperature disturbance sequence, respectively, for the t-th steady-state period. and , respectively, are the mean values ​​of all normalized mutual information in the humidity disturbance sequence and temperature disturbance sequence of the t-th steady-state period.

[0008] Preferably, the Hilbert-Huang transform is used to obtain the total instantaneous interference frequency at each time point in the humidity interference sequence and the total instantaneous interference frequency at each time point in the temperature interference sequence, and then normalization is performed.

[0009] Preferably, the mutual information degree between each error fluctuation value and each relative humidity display value and each temperature display value within each sliding time window is obtained by using a sliding mutual information algorithm, and then normalized.

[0010] Preferably, before obtaining the significance of the interference, an anomaly detection algorithm is used to obtain the local outlier factors of each coupled interference degree.

[0011] Preferably, the formula for obtaining the significance of the disturbance in each steady-state cycle is: In the formula, Let be the significance of the disturbance in the t-th steady-state period. The maximum value normalization function, Let be the local outlier factor of the coupling disturbance degree in the t-th steady-state period. Let be the coupling disturbance degree in the t-th steady-state period. The mean of the coupling disturbance degree over all steady-state cycles. This is the preset first parameter.

[0012] Preferably, the selection process for the high-quality calibration points is as follows: Determine whether the significance of disturbances in all steady-state cycles conforms to a normal distribution. If not, perform a Box-Cox transformation to convert the significance of disturbances in all steady-state cycles to a normal distribution. If they conform to a normal distribution, no transformation is needed. The significance of interference in all steady-state cycles is used as input for the Grubbs test. The Grubbs test is used to identify abnormal steady-state cycles. If there are no abnormal steady-state cycles, all preset calibration points are considered high-quality calibration points. If there are abnormal steady-state cycles, the preset calibration points corresponding to the abnormal steady-state cycles are judged as inferior and directly removed. The remaining preset calibration points that have not been removed are merged into the set of high-quality calibration points.

[0013] This application also provides a humidity sensor calibration system for a portable temperature and humidity generator, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of the humidity sensor calibration method for a portable temperature and humidity generator described above.

[0014] As can be seen from the above, the humidity sensor calibration system and method for a portable temperature and humidity generator provided in this application have at least the following beneficial effects: This application takes into account that the output values ​​of humidity sensors at different preset calibration points are significantly affected by the coupling interference of ambient temperature and humidity. By analyzing the changes in the error fluctuation of the sensor output value affected by the interference of relative humidity fluctuation, and combining the frequency characteristics of the interference of ambient temperature and humidity on the output value of the humidity sensor, the coupling interference of ambient temperature and humidity on the output value of the humidity sensor can be accurately measured, which is beneficial to the subsequent accurate and effective inspection of the quality of the preset calibration points. To more reliably verify the quality of preset calibration points, this invention uses the local outlier characteristics of coupling interference for coefficient compensation, which more reliably measures the degree to which the output value of the humidity sensor is affected by the coupling interference of ambient temperature and humidity, thereby improving the reliability of obtaining high-quality calibration points in the future. This application uses Grubbs' test to assess the significance of interference in all steady-state cycles, thereby more reliably identifying the existence of abnormal steady-state cycles. This allows for accurate and effective verification of the quality of preset calibration points and the acquisition of high-quality calibration points. Based on these high-quality calibration points, the humidity sensor is calibrated, improving the accuracy of humidity sensor calibration and better meeting the requirements for high-precision humidity sensors. Attached Figure Description

[0015] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A flowchart illustrating the steps of a humidity sensor calibration method for a portable temperature and humidity generator provided in this application. Detailed Implementation

[0017] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a humidity sensor calibration system and method for a portable temperature and humidity generator proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0018] Unless otherwise specified and limited, terms such as “comprising,” “including,” or any other variations thereof are intended to cover a non-exclusive inclusion, such that a circuit structure, article, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the article or device that includes said element. Furthermore, the term “and / or” as used herein includes any and all combinations of one or more of the associated listed items. All technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0019] The following description, in conjunction with the accompanying drawings, details the specific scheme of the humidity sensor calibration system and method for a portable temperature and humidity generator provided in this application.

[0020] Please see Figure 1The document illustrates a flowchart of a humidity sensor calibration method for a portable temperature and humidity generator according to an embodiment of this application, including the following steps: Step 1: Read and record the relative humidity display value and humidity sensor output value at the preset calibration point, and simultaneously collect the relative humidity display value, temperature display value, and humidity sensor output value in each steady-state cycle.

[0021] To enable on-site verification and calibration of humidity sensors, this invention uses a portable temperature and humidity generator for calibration. The portable temperature and humidity generator includes a dryer, a saturator, a measuring chamber, a gas circulation system, and a temperature and humidity measurement and control system. The dryer is a drying device that provides a dry air source; the saturator is a device that provides humid air containing saturated water vapor; the measuring chamber provides the temperature and humidity environment and houses the humidity sensor to be tested; the gas circulation system uses a miniature vacuum pump to circulate the airflow; and the temperature and humidity measurement and control system performs high-precision measurement of the temperature and humidity environment within the measuring chamber and provides closed-loop control of the temperature and humidity environment within the measuring chamber.

[0022] Among them, the portable temperature and humidity generator has a temperature control instrument that can display temperature and humidity. It can generate a temperature and humidity environment with a relative humidity range of 5%RH to 95%RH and a temperature range of 5℃ to 50℃. It has the function of quickly responding to changes in temperature and humidity, providing a reliable environmental basis for humidity sensor calibration.

[0023] When calibrating a humidity sensor using a portable temperature and humidity generator, remove the plug from the lockable hole on the sealing cover of the measuring chamber, install the humidity sensor to be calibrated into the measuring chamber, and then tighten the lockable hole.

[0024] Furthermore, in this embodiment, the temperature inside the measurement room is maintained at 20℃ or 25℃ in constant temperature mode, with an allowable ambient temperature fluctuation of less than or equal to ±0.5℃. Then, a portable temperature and humidity generator is used to calibrate the humidity sensor, following a sequence from low humidity to high humidity. Specifically, humidification is increased from 5%RH to 95%RH, with each 5%RH increment serving as a preset calibration point. After reaching a preset calibration point, a period of maintaining temperature and humidity before reading the final relative humidity display value is considered a steady-state cycle. For each preset calibration point, the relative humidity display value and humidity sensor output value are read and recorded using a temperature control instrument.

[0025] Meanwhile, in order to more effectively analyze the influence of the coupling interference of ambient temperature and humidity on the output values ​​of the humidity sensor at different preset calibration points, within the steady-state period after the portable temperature and humidity generator reaches each preset calibration point, the preset time of the steady-state period is 3 minutes. The relative humidity display value, temperature display value and humidity sensor output value are collected at 1 second acquisition intervals within each steady-state period, and recorded as the steady-state relative humidity sequence, steady-state temperature sequence and steady-state humidity output value sequence for each steady-state period.

[0026] Among them, the fluctuations that occur in the steady state stage are coupled oscillation interferences, which can effectively analyze the influence of the coupled interference of ambient temperature and humidity on the output value of the humidity sensor.

[0027] Step 2: By observing the coupling interference of the humidity sensor's output value with respect to ambient temperature and humidity during each steady-state cycle, the coupling interference degree of each steady-state cycle is obtained.

[0028] Since the output values ​​of humidity sensors at different preset calibration points are significantly affected by the coupling interference of ambient temperature and humidity, in order to improve the accuracy of humidity sensor calibration, it is necessary to fully consider the influence of the coupling interference of ambient temperature and humidity on the output values ​​of humidity sensors, and to verify the quality of preset calibration points, so as to achieve humidity sensor calibration based on high-quality calibration points.

[0029] Therefore, in order to analyze the influence of the coupling interference of ambient temperature and humidity on the output value of the humidity sensor, for each steady-state cycle, the difference sequence between the steady-state relative humidity sequence and the steady-state humidity output value sequence is calculated and denoted as the error fluctuation sequence. This reflects the error fluctuation between the relative humidity display value and the sensor output value. The error fluctuation sequence, steady-state relative humidity sequence, and steady-state temperature sequence are normalized to eliminate the dimensional conflict between different parameters. There are many normalization methods, such as maximum value normalization or range normalization. In this embodiment, the normalization process adopts the maximum value normalization method. The specific process is existing technology and will not be described in detail.

[0030] It should be noted that, in this embodiment, to avoid the denominator being zero, a very small positive number (in this embodiment, the value is...) is added to the denominator term when performing normalization and fractional calculations at various points. This is to prevent calculation crashes caused by the denominator being zero when the maximum or range is 0 due to perfectly stationary data.

[0031] Furthermore, the normalized error fluctuation sequence and steady-state relative humidity sequence are used as inputs to the sliding mutual information algorithm. The sliding time window size is 21s, and the sliding time step is 1s. The sliding mutual information algorithm is used to obtain the mutual information degree between the error fluctuation and the relative humidity display value within each sliding time window. The mutual information degrees calculated within all sliding time windows are sorted in chronological order and recorded as the humidity interference sequence for each steady-state period. The maximum value of the mutual information degree within the humidity interference sequence is normalized to eliminate dimensional conflicts in subsequent calculations. The humidity interference sequence reflects the change in the error fluctuation of the sensor output value due to the interference of the relative humidity display value.

[0032] It should be noted that the sliding time step of the sliding window is the same as the acquisition time interval. The center position of the sliding time window can be represented as the time point at the center position of the sliding time window, so each sliding time window corresponds to a time point.

[0033] Similarly, using the same sliding mutual information algorithm and sorting method, the normalized error fluctuation sequence and steady-state temperature sequence are used as inputs to the sliding mutual information algorithm. The algorithm obtains the mutual information degree between the error fluctuation and the displayed temperature value within each sliding time window, and constructs a temperature interference sequence for each steady-state period. The mutual information degree within the temperature interference sequence is then normalized to eliminate dimensional conflicts in subsequent calculations. The temperature interference sequence reflects the change in error fluctuation of the sensor output value due to interference from the displayed temperature value. The specific normalization process is existing technology, and this embodiment does not impose special limitations on it; the specific process will not be elaborated upon.

[0034] Since the output values ​​of humidity sensors are affected by different frequencies of interference from ambient temperature and humidity, the closer the frequencies of interference from ambient temperature and humidity are to the output values ​​of humidity sensors, and the higher the degree of superimposed interference from ambient temperature and humidity, the more significant the coupled interference from ambient temperature and humidity is to the output values ​​of humidity sensors. Therefore, to more accurately analyze the coupled interference from ambient temperature and humidity on the output values ​​of humidity sensors, the humidity interference sequence and temperature interference sequence of each steady-state period are used as inputs to the Hilbert-Huang Transform. The Hilbert-Huang Transform is used to obtain the instantaneous total interference frequency at each time point in the humidity interference sequence and the temperature interference sequence, respectively. The instantaneous total interference frequency at each time point in both sequences is then normalized to eliminate the dimension of the instantaneous interference frequency, reflecting the average level of the interference frequency of ambient temperature and humidity on the output values ​​of humidity sensors at each time point.

[0035] Based on the above analysis, the coupling interference degree for each steady-state cycle is calculated: In the formula, Let be the coupling disturbance degree in the t-th steady-state period. It is an exponential function with the natural constant as its base. and Let be the mean of all normalized instantaneous total frequencies of the humidity disturbance sequence and temperature disturbance sequence, respectively, for the t-th steady-state period. and , respectively, are the mean values ​​of all normalized mutual information in the humidity disturbance sequence and temperature disturbance sequence of the t-th steady-state period.

[0036] It should be noted that this calculation formula is based on an empirical feature model built on data-driven principles, which aims to quantify the statistical correlation and discrete significance of multidimensional data sequences in the feature space through dimensionless numerical combinations.

[0037] In this embodiment, the above formula, based on existing feature measurement methods, uses absolute difference to measure the proximity of the instantaneous total interference frequency between different variables. It then uses the exponential negative mapping result of the proximity to perform gain compensation on the coefficient 1 of the superimposed interference degree. The superimposed interference degree is measured by the sum of the mutual information in different interference sequences. Therefore, by combining the product of the gain-compensated coefficient and the superimposed interference degree, the measurement and analysis of the coupling interference degree is achieved.

[0038] Among them, the coupling interference degree reflects the influence of the coupling interference of ambient temperature and humidity on the output value of the humidity sensor in each steady-state cycle. The greater the coupling interference degree, the higher the influence of the coupling interference of ambient temperature and humidity on the output value of the humidity sensor in the steady-state cycle. At this time, the quality of the preset calibration point before the steady-state cycle is more likely to be seriously affected, resulting in the inability to accurately calibrate the error value of the humidity sensor output value. Therefore, it is necessary to further check the quality of the preset calibration point.

[0039] Step 3: By analyzing the degree to which the output value of the humidity sensor is affected by the coupling interference of ambient temperature and humidity, the interference significance of each steady-state cycle is obtained, and the quality of the preset calibration point is checked based on the interference significance using the Grubbs test.

[0040] Furthermore, the coupling disturbance degree of all steady-state cycles is used as input to the Local Outlier Factor (LOF) algorithm. The LOF algorithm is used to obtain the local outlier factor of the coupling disturbance degree for each steady-state cycle, and the number of neighborhood samples for the LOF algorithm is set. A relatively small constant (in this embodiment) The larger the local outlier factor, the higher the degree of abnormality of the humidity sensor output value under the coupling interference of environmental temperature and humidity within the steady-state period. The more serious the impact on the quality of the preset calibration point before the steady-state period, the less conducive it is to high-precision error calibration of the humidity sensor output value.

[0041] To more reliably verify the quality of the preset calibration points, the coupling interference degree of each steady-state cycle is compensated by the local outlier factor of the coupling interference degree. This allows for a more reliable measurement of the interference significance of each steady-state cycle. The greater the coupling interference degree and the larger the local outlier factor, the higher the significance of the severe impact on the quality of the preset calibration points before that steady-state cycle.

[0042] Based on the above analysis, the significance of the disturbance in each steady-state period is calculated: In the formula, Let be the significance of the disturbance in the t-th steady-state period. The maximum value normalization function, Let be the local outlier factor of the coupling disturbance degree in the t-th steady-state period. Let be the coupling disturbance degree in the t-th steady-state period. The mean of the coupling disturbance degree over all steady-state cycles. The first parameter is preset to avoid the numerator and denominator being 0. Its value range is 0.1-0.2, and it is 0.15 in this implementation.

[0043] Similarly, this calculation formula is an empirical feature model based on data-driven construction, which aims to quantify the statistical correlation and discrete significance of multidimensional data sequences in the feature space through dimensionless numerical combinations.

[0044] In this embodiment, based on existing feature measurement methods, the local outlier factor can reflect the degree of abnormality of the humidity sensor output value affected by the coupling interference of environmental temperature and humidity. The formula uses the normalized result of the maximum value of the local outlier factor to compensate for coefficient 1. At the same time, the square of the ratio between the coupling interference degree and the mean of the coupling interference degree is used to more significantly highlight the level of influence of coupling interference on the humidity sensor output value in each steady-state cycle, thereby realizing the measurement of the significance of interference.

[0045] Understandably, the significance of interference reflects the degree to which the output value of the humidity sensor is affected by the coupling interference of ambient temperature and humidity. The greater the significance of interference, the more significant the influence of the coupling interference of ambient temperature and humidity on the output value of the humidity sensor within the steady-state period. In this case, the higher the credibility of the quality of the preset calibration point before the steady-state period being severely affected, the more it affects the accuracy of the humidity sensor calibration.

[0046] Furthermore, in order to accurately and effectively verify the quality of the preset calibration points, the Shapiro-Wilk normality test is performed on the interference significance of all steady-state cycles to determine whether the interference significance of all steady-state cycles conforms to a normal distribution. If it does not conform, the Box-Cox transformation is used to transform the interference significance of all steady-state cycles to a normal distribution; if it conforms to a normal distribution, no transformation is required.

[0047] Furthermore, the significance of interference in all steady-state cycles is used as input for the Grubbs test, with a preset Grubbs threshold of 2.708. The Grubbs test is used to identify whether abnormal steady-state cycles exist. Specifically, if no abnormal steady-state cycles exist, the humidity sensor output value is less affected by the coupling interference of ambient temperature and humidity within each steady-state cycle, and all preset calibration points are considered high-quality calibration points. If abnormal steady-state cycles exist, the preset calibration points corresponding to the abnormal steady-state cycles are judged as inferior and directly removed, while the remaining preset calibration points are incorporated into the set of high-quality calibration points.

[0048] Step 4: Using the nonlinear least squares method, obtain the fitting function between the relative humidity display value and the humidity sensor output value based on the high-quality calibration points to calibrate the humidity sensor.

[0049] To improve the accuracy of humidity sensor calibration, in this embodiment, the relative humidity display values ​​and humidity sensor output values ​​of all high-quality calibration points in the high-quality calibration point set are used as inputs to the nonlinear least squares method. The relative humidity display value is used as the dependent variable, and the humidity sensor output value is used as the independent variable. The fitting model adopts a cubic polynomial regression model. The nonlinear least squares method is used to obtain the fitting function between the relative humidity display value and the humidity sensor output value, thereby realizing the calibration of the humidity sensor.

[0050] When using the calibrated humidity sensor for relative humidity measurement, it is necessary to keep the ambient temperature stable (e.g., keep the ambient temperature stable at 20℃ or 25℃), input the output value of the calibrated humidity sensor into the fitting function, and calculate the calibrated relative humidity through the fitting function to meet the requirements of high-precision humidity sensor.

[0051] Based on the same inventive concept as the above method, this application also provides a humidity sensor calibration system for a portable temperature and humidity generator, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of the humidity sensor calibration method for a portable temperature and humidity generator described above.

[0052] It is understood that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, the above description focuses on specific embodiments of this specification. Additionally, the processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some implementations, multitasking and parallel processing are possible or may be advantageous.

[0053] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0054] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Any equivalent structural or procedural transformations made based on the description and drawings of this application, or direct or indirect applications in other related technical fields, are similarly included within the protection scope of this application.

Claims

1. A method for calibrating the humidity sensor of a portable temperature and humidity generator, characterized in that, Includes the following steps: Read and record the relative humidity display value and humidity sensor output value at the preset calibration point, and simultaneously collect the relative humidity display value, temperature display value and humidity sensor output value in each preset steady-state cycle; The degree of difference between the relative humidity display value and the output value of the humidity sensor is analyzed, and the correlation between this degree of difference and the relative humidity display value and the temperature display value is used to obtain the coupling interference degree for each steady-state cycle. By analyzing the local discrete characteristics of the coupling interference degree in each steady-state cycle and the average distribution level of the coupling interference degree, the interference significance of each steady-state cycle is obtained. The Grubbs test is then used to verify the preset calibration points and select high-quality calibration points. The relative humidity display value is fitted to the humidity sensor output value based on the high-quality calibration point to achieve the calibration of the humidity sensor.

2. The humidity sensor calibration method for a portable temperature and humidity generator as described in claim 1, characterized in that, During the process of increasing indoor humidity, each preset value corresponds to a preset calibration point. After reaching each preset calibration point, there is a steady-state period. After reaching the preset calibration point, the period of heat preservation and humidification before reading the final relative humidity display value is taken as a steady-state period.

3. The method for calibrating the humidity sensor of a portable temperature and humidity generator as described in claim 1, characterized in that, Before obtaining the coupling interference degree for each steady-state cycle, the relative humidity display value, temperature display value, and humidity sensor output value in each steady-state cycle are recorded as the steady-state relative humidity sequence, steady-state temperature sequence, and steady-state humidity output value sequence for each steady-state cycle. The difference sequence between the steady-state relative humidity sequence and the steady-state humidity output value sequence is recorded as the error fluctuation sequence.

4. The humidity sensor calibration method for a portable temperature and humidity generator as described in claim 3, characterized in that, The formula for obtaining the coupling interference degree for each steady-state cycle is: In the formula, Let be the coupling disturbance degree in the t-th steady-state period. It is an exponential function with the natural constant as its base. and Let be the mean of all normalized instantaneous total frequencies of the humidity disturbance sequence and temperature disturbance sequence, respectively, for the t-th steady-state period. and , respectively, are the mean values ​​of all normalized mutual information in the humidity disturbance sequence and temperature disturbance sequence of the t-th steady-state period.

5. The humidity sensor calibration method for a portable temperature and humidity generator as described in claim 4, characterized in that, The Hilbert-Huang transform was used to obtain the total instantaneous interference frequency at each time point in the humidity interference sequence and the total instantaneous interference frequency at each time point in the temperature interference sequence, and then normalized the results.

6. The humidity sensor calibration method for a portable temperature and humidity generator as described in claim 4, characterized in that, The mutual information degree between each error fluctuation value and each relative humidity display value and each temperature display value within each sliding time window is obtained by using the sliding mutual information algorithm, and then normalized.

7. The method for calibrating the humidity sensor of a portable temperature and humidity generator as described in claim 1, characterized in that, Before obtaining the significance of the interference, an anomaly detection algorithm is used to obtain the local outlier factors of each coupled interference degree.

8. The humidity sensor calibration method for a portable temperature and humidity generator as described in claim 1, characterized in that, The formula for obtaining the significance of the disturbance in each steady-state cycle is: In the formula, Let be the significance of the disturbance in the t-th steady-state period. The maximum value normalization function, Let be the local outlier factor of the coupling disturbance degree in the t-th steady-state period. Let be the coupling disturbance degree in the t-th steady-state period. The mean of the coupling disturbance degree over all steady-state cycles. This is the preset first parameter.

9. The method for calibrating the humidity sensor of a portable temperature and humidity generator as described in claim 1, characterized in that, The process for selecting the high-quality calibration points is as follows: Determine whether the significance of disturbances in all steady-state cycles conforms to a normal distribution. If not, perform a Box-Cox transformation to convert the significance of disturbances in all steady-state cycles to a normal distribution. If they conform to a normal distribution, no transformation is needed. The significance of interference in all steady-state cycles is used as input for the Grubbs test. The Grubbs test is used to identify abnormal steady-state cycles. If there are no abnormal steady-state cycles, all preset calibration points are considered high-quality calibration points. If there are abnormal steady-state cycles, the preset calibration points corresponding to the abnormal steady-state cycles are judged as inferior and directly removed. The remaining preset calibration points that have not been removed are merged into the set of high-quality calibration points.

10. A humidity sensor calibration system for a portable temperature and humidity generator, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the humidity sensor calibration method for a portable temperature and humidity generator as described in any one of claims 1-9.

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