Temperature sensor calibration method

Abstract

The invention discloses a temperature sensor calibration method, which comprises the following steps: firstly, measuring the maximum and minimum voltage differences of a temperature sensor in a reference temperature environment, and setting a plurality of reference voltage difference measurement points; then, receiving an internal reference voltage and an external calibration voltage of the sensor for calculating reference and standard temperature parameters corresponding to each voltage difference; through deep analysis, the linear and nonlinear relationship between each voltage difference and the initial temperature adjustment value is calculated, and the output characteristics of the temperature sensor are comprehensively considered; the nonlinear part is independently processed, so that the calibration accuracy is ensured; and finally, a target compensation temperature value of the temperature sensor is calculated according to the initial temperature adjustment value, and accurate calibration is realized. The method effectively improves the accuracy and stability of temperature measurement, and is suitable for occasions requiring high-precision temperature measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature sensors, and in particular to a temperature sensor calibration method. Background Art

[0002] With the increasingly wide application of temperature sensors in various fields, the requirements for the calibration accuracy and accuracy of temperature sensors are also getting higher and higher. Especially in high-precision measurement and automatic control systems, tiny calibration errors may lead to serious consequences. Therefore, a more precise and flexible temperature sensor calibration method is needed.

[0003] The invention patent with the patent application number 202110777476.6 discloses a temperature sensor calibration method, which obtains the first voltage difference in the first temperature environment; receives the first reference voltage, and calculates the first temperature value according to the first voltage difference and the first reference voltage; receives the standard reference voltage, and calculates the standard temperature value according to the first voltage difference and the standard reference voltage; calculates the compensation temperature value, and the compensation temperature value is the difference between the standard temperature value and the first temperature value; adjusts the output of the temperature sensor according to the compensation temperature value. The temperature sensor calibration method provided by the present invention can obtain the compensation temperature value by connecting the temperature sensor to the standard reference voltage, and then compensate the output of the temperature sensor, which can avoid the problems of poor compensation effect and low accuracy caused by analog-to-digital conversion during the compensation process, and is applicable to the calibration of a large number of temperature sensors.

[0004] However, the temperature sensor calibration method depends on a single voltage difference and an external standard reference voltage for calculation, and is easily affected by factors such as environmental temperature stability, the non-linear characteristics of the temperature sensor, and measurement noise, resulting in insufficient calibration accuracy and accuracy. Summary of the Invention

[0005] By providing a temperature sensor calibration method, the present application accurately calculates the compensation temperature value and realizes high-precision calibration of the temperature sensor.

[0006] The present application provides a temperature sensor calibration method, including:

[0007] S1, obtaining the maximum voltage difference and the minimum voltage difference output by the temperature sensor in the reference temperature environment, and setting the reference voltage difference measurement points;

[0008] S2, receiving the internal reference voltage preset in the temperature sensor and the external calibration voltage connected externally;

[0009] S3, calculating the reference temperature parameter and the standard temperature parameter of each voltage difference;

[0010] S4. Calculate the linear and non - linear relationships of each voltage difference with respect to the preliminary temperature adjustment value;

[0011] S5. Calculate the target compensation temperature value of the temperature sensor based on the preliminary temperature adjustment value.

[0012] Preferably, the maximum voltage difference and the minimum voltage difference include: testing the temperature sensor in a reference temperature environment which is a known and stable reference temperature environment. At this temperature, record the maximum voltage difference V_max and the minimum voltage difference V_min output by the temperature sensor.

[0013] Preferably, S4, calculating the linear and non - linear relationships of each voltage difference with respect to the preliminary temperature adjustment value, includes:

[0014] S41. For each reference voltage difference measurement point, use the calculated reference temperature parameter and the standard temperature parameter to calculate the preliminary temperature adjustment value;

[0015] S42. Collect the preliminary temperature adjustment values and the corresponding voltage differences of all reference voltage difference measurement points to form a data set;

[0016] S43. Use the least - squares method to perform linear fitting on the preliminary temperature adjustment value and the voltage difference to obtain a linear relationship formula; where the linear relationship formula is ΔT 线n = k * ΔV n + b, where ΔV n is the voltage difference within the range of the maximum voltage difference and the minimum voltage difference, k is the linear slope, and b is the linear intercept;

[0017] S44. For the voltage differences and preliminary temperature adjustment values that cannot be fitted, record them as non - linear relationships;

[0018] S45. Organize the linear and non - linear relationships between the voltage difference and the preliminary temperature adjustment value to form a calibration curve.

[0019] Preferably, S5, calculating the target compensation temperature value of the temperature sensor based on the preliminary temperature adjustment value, specifically includes:

[0020] S51. Record the preliminary temperature adjustment value and the corresponding working time when the temperature sensor is working;

[0021] S52. Use linear regression statistics to establish a mathematical model between the preliminary temperature adjustment value and the working time; where the mathematical model between the preliminary temperature adjustment value and the time is ΔT n = f(t), where f(t) is a function of time t, and ΔT n is the preliminary temperature adjustment value;

[0022] S53. Analyze the law of change of the preliminary temperature adjustment value over time based on the established mathematical model; the value of time t obtained from the mathematical model is T 理论 (t), and the time offset is ΔT(t). Then the calculation formula for the time offset is: ΔT(t) = ΔT n -T 理论 (t);

[0023] S54. Calculate the target compensation temperature value according to the mathematical relationship between the preliminary temperature adjustment value and the time offset.

[0024] Preferably, in S54, the target compensation temperature value includes: the calculation formula for the target compensation temperature value is: T c (t) = ΔT n -ΔT(t).

[0025] Preferably, in S45, organizing the linear and non-linear relationships between the voltage difference and the preliminary temperature adjustment value includes:

[0026] S451. Adjust the reference temperature environment after determining the non-linear characteristics and trends;

[0027] S452. Define a temperature environment change factor to describe the influence of the temperature environment on the non-linearly adjusted temperature value;

[0028] S453. Calculate the influence coefficient of the temperature environment on the non-linearly adjusted temperature value according to the temperature environment change factor and the preliminary temperature adjustment value;

[0029] S454. Establish the mapping relationship between the environmental parameters and the calibration parameters under different temperature environments;

[0030] S455. Use the calculated temperature adjustment influence coefficient to correct the non-linear preliminary temperature adjustment number;

[0031] S456. Establish a calibration curve with the temperature adjustment influence coefficient, the voltage difference, the preliminary temperature adjustment value, and the corrected temperature adjustment value.

[0032] Preferably, it includes: ΔT e is the temperature environment change factor, representing the difference between the current temperature environment and the reference temperature environment, which can be a positive or negative value depending on whether the current temperature is higher or lower than the reference temperature; through multiple tests, determine the relationship between the temperature environment change factor and the preliminary temperature adjustment value, and calculate an influence coefficient k based on this relationship.

[0033] Preferably, S455 includes: the correction formula is: ΔT n =ΔT 非n +k*ΔT e , ΔTn is the preliminary temperature adjustment value, ΔT 非n is the preliminary temperature adjustment value under non-linear relationship conditions, k is the influence coefficient of the temperature environment on the non-linear adjusted temperature value, ΔT e is the temperature environment change factor.

[0034] Preferably, the step S4 further includes:

[0035] S4a, analyzing the characteristics of the calculated linear and non-linear relationships;

[0036] S4b, segmenting the voltage difference measurement points according to the linear and non-linear characteristics;

[0037] S4c, analyzing the voltage difference measurement points within each segment to find out the law of their change with temperature;

[0038] S4d, determining an advance point representing the linear or non-linear characteristics of each segment within each segment;

[0039] S4e, establishing the calibration logic of the temperature sensor according to the segmentation result and the advance point information;

[0040] S4f, when the temperature sensor is powered on next time, being able to perform real-time and rapid calibration according to the characteristic parameters of the ambient temperature and the voltage difference.

[0041] Preferably, it includes: the reference temperature parameter is the reference temperature parameter corresponding to each voltage difference, and the reference temperature parameter has a positive correlation with the reference temperature value T p The formula is: Vref(p) is the internal reference voltage, K p is the temperature coefficient corresponding to the internal reference voltage, μ p is the reference temperature parameter; the standard temperature parameter has a positive correlation with the standard temperature value T s The formula is: ΔV n is the voltage difference, Vref(s) is the external calibration voltage, K s is the temperature coefficient corresponding to the external calibration voltage, μ s is the standard temperature parameter; the preliminary temperature adjustment value is the subtraction of the standard temperature value from the reference temperature value, and the formula is ΔT n =|T s -T p |, ΔT 线n and ΔT 非n are the preliminary temperature adjustment values under linear and non-linear relationship conditions, and are combined as ΔT during calculation n .

[0042] One or more technical solutions provided in the present application have at least the following technical effects or advantages:

[0043] By obtaining the maximum voltage difference and the minimum voltage difference of the temperature sensor in a reference temperature environment and setting multiple reference voltage difference measurement points, a basis for accurate calibration is provided. Using the internal reference voltage and the external calibration voltage, the preliminary temperature parameter and the standard temperature parameter are calculated respectively, effectively combining the characteristics of the temperature sensor itself and the calibration advantage of the external high-precision voltage. Further, by calculating the linear and non-linear relationships of each voltage difference with respect to the preliminary temperature parameter, not only the linear output characteristics of the temperature sensor are considered, but also the possible non-linear factors are taken into account, improving the accuracy and comprehensiveness of the calibration. In particular, the least squares method is used to perform linear fitting on the preliminary temperature adjustment value and the voltage difference to obtain a specific linear relationship. At the same time, for the part that cannot be fitted by the linear relationship, it is recorded as a non-linear relationship and processed separately, further ensuring the accuracy and reliability of the calibration. Finally, the target compensation temperature value required by the temperature sensor is calculated based on the preliminary temperature adjustment value, realizing the accurate calibration of the temperature sensor and significantly improving the accuracy and stability of temperature measurement.

[0044] By carefully recording the preliminary temperature adjustment value and the corresponding working time of the temperature sensor during operation and using the linear regression statistical method to establish a mathematical model between the two, the accuracy and reliability of temperature compensation are significantly improved. This solution not only considers the output characteristics of the temperature sensor itself, but also deeply analyzes its variation law over time, enabling the temperature compensation to dynamically adapt to the working state of the temperature sensor. By calculating the time offset, this solution can accurately capture the difference between the actual working time of the temperature sensor and the theoretical value, and then calculate a more accurate target compensation temperature value through a mathematical relationship. The implementation of this technical solution effectively improves the accuracy and stability of temperature control, providing strong technical support for the accurate compensation of temperature sensors.

[0045] By comprehensively considering the non-linear characteristics of the voltage difference and the preliminary temperature adjustment value of the temperature sensor and the changes in the temperature environment, accurate calibration of the temperature sensor in a complex environment is achieved. The accuracy and reliability of the calibration are improved, making the output of the temperature sensor closer to the actual temperature value. At the same time, by introducing the temperature environment change factor and the influence coefficient, the calibration process is refined, enhancing the adaptability and flexibility of the calibration. In addition, establishing the mapping relationship between the environmental parameters and the calibration parameters and drawing the calibration curve greatly improves the efficiency and accuracy of the calibration.

[0046] By deeply analyzing the linear and non-linear relationship characteristics of the temperature sensor, setting corresponding thresholds for quantification, and combining piecewise processing and the concept of advance points, the calibration accuracy and reliability of the temperature sensor are greatly improved. This solution can not only more accurately identify the segment to which the current voltage difference belongs, but also perform fine calibration according to the segment characteristics and advance points, thus effectively adapting to the actual differences between different temperature sensors, making the calibration results more reliable and accurate, and meeting the requirements of high-precision temperature measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a schematic flowchart of a temperature sensor calibration method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] To facilitate the understanding of the present invention, the present application will be described more comprehensively with reference to the relevant drawings; the preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein; on the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs; the terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0050] Embodiment 1: Figure 1 It is a schematic flowchart of a temperature sensor calibration method according to an embodiment of the present invention.

[0051] As Figure 1 shown, a temperature sensor calibration method includes the following steps:

[0052] S1. Obtain the maximum voltage difference and the minimum voltage difference output by the temperature sensor in a reference temperature environment, and set reference voltage difference measurement points.

[0053] Among them, the reference temperature environment is to test the temperature sensor in a reference temperature environment with a known and stable temperature (such as 25°C). At this temperature, record the maximum voltage difference (V_max) and the minimum voltage difference (V_min) output by the temperature sensor.

[0054] The reference voltage difference measurement points are to set multiple reference voltage difference measurement points (such as V1, V2,..., Vn) within the range of the maximum voltage difference and the minimum voltage difference to calibrate the temperature sensor more precisely. The voltage differences herein are all reference voltage difference measurement points.

[0055] S2, receive the internal reference voltage preset in the temperature sensor and the external calibration voltage externally connected.

[0056] Among them, the internal reference voltage is a reference voltage preset inside the temperature sensor for calculating temperature. This voltage is fixed and known. The internal reference voltage is used to compare or calculate with the detected voltage difference to obtain a preliminary temperature value. The externally provided high-precision and stable voltage value is used to calibrate the temperature sensor. Ensure the accuracy and stability of the external calibration voltage to improve the reliability of calibration.

[0057] S3, calculate the reference temperature parameter and the standard temperature parameter for each voltage difference.

[0058] Specifically, the reference temperature parameter and the standard temperature parameter include:

[0059] S31, for each voltage difference, calculate its ratio to the internal reference voltage to obtain the reference temperature parameter.

[0060] Among them, the reference temperature parameter is the reference temperature parameter corresponding to each voltage difference. The reference temperature parameter has a positive correlation with the reference temperature value T p (The reference temperature parameter is obtained by calculating the ratio of each voltage difference to the internal reference voltage. During the calibration process of the temperature sensor, as the temperature changes, the voltage difference will change accordingly, while the internal reference voltage remains unchanged. Therefore, when the temperature increases, the voltage difference increases, and the reference temperature parameter also increases; conversely, when the temperature decreases, the voltage difference decreases, and the reference temperature parameter also decreases. This indicates that there is a positive correlation between the reference temperature parameter and the reference temperature value), which reflects the temperature reading of the temperature sensor before calibration. The formula is:

[0061]

[0062] ΔV n is the voltage difference, Vref(p) is the internal reference voltage, K p is the temperature coefficient corresponding to the internal reference voltage (Although the internal reference voltage remains unchanged, its corresponding temperature coefficient reflects the degree of change of the internal characteristics of the temperature sensor with temperature. Adding the temperature coefficient can make the calculation of the reference temperature parameter more accurate and can more truly reflect the temperature reading of the temperature sensor before calibration), μ p is the reference temperature parameter.

[0063] S32, calculate the ratio of each voltage difference to the external calibration voltage to obtain the standard temperature parameter.

[0064] Among them, the standard temperature parameter has a positive correlation with the standard temperature value T sThere is a positive correlation (the standard temperature parameter is obtained by calculating the ratio of the voltage difference to the external calibration voltage. During the calibration process, the external calibration voltage maintains high precision and stability, while the voltage difference changes with temperature. Therefore, when the temperature increases, the voltage difference increases, and the standard temperature parameter also increases; conversely, when the temperature decreases, the voltage difference decreases, and the standard temperature parameter also decreases. This indicates that there is also a positive correlation between the standard temperature parameter and the standard temperature value), which is used to calibrate the readings of the temperature sensor. The formula is:

[0065]

[0066] ΔV n is the voltage difference, Vref(s) is the external calibration voltage, and K s is the temperature coefficient corresponding to the external calibration voltage (although the external calibration voltage maintains high precision and stability, it may fluctuate slightly due to environmental factors in actual applications. Adding the temperature coefficient can further calibrate this fluctuation, making the calculation of the standard temperature parameter more accurate and reliable. At the same time, this also reflects the interaction relationship between the temperature sensor and the external calibration voltage), and μ s is the standard temperature parameter.

[0067] S4. Calculate the linear and non-linear relationships of each voltage difference with respect to the preliminary temperature adjustment value.

[0068] Among them, the preliminary temperature adjustment value is obtained by subtracting the reference temperature value from the standard temperature value. The formula is ΔT n =|T s -T p |.

[0069] Specifically, calculating the linear and non-linear relationships of each voltage difference with respect to the preliminary temperature adjustment value includes:

[0070] S41. For each reference voltage difference measurement point, use the calculated reference temperature parameter and standard temperature parameter to calculate the preliminary temperature adjustment value, that is, the difference between the standard temperature value and the preliminary temperature value.

[0071] S42. Collect the preliminary temperature adjustment values and the corresponding voltage differences of all reference voltage difference measurement points to form a data set.

[0072] S43. Use the least squares method to perform linear fitting on the preliminary temperature adjustment value and the voltage difference to obtain a linear relationship formula.

[0073] Among them, the linear relationship formula is ΔT 线n =k*ΔV n +b, where ΔV nis the voltage difference within the range of the maximum voltage difference and the minimum voltage difference, k is the linear slope, b is the linear intercept, and is calculated by the least squares method.

[0074] S44. For the voltage difference and the preliminary temperature adjustment value that cannot be fitted, they are denoted as a non-linear relationship.

[0075] Specifically, those with no linear relationship between the voltage difference and the preliminary adjustment value are denoted as non-linear relationships and are separately processed in subsequent operations. The preliminary temperature adjustment value for the non-linear relationship is ΔT 非n .

[0076] S45. Organize the linear and non-linear relationships between the voltage difference and the preliminary temperature adjustment value to form a calibration curve.

[0077] S5. Calculate the target compensation temperature value of the temperature sensor according to the preliminary temperature adjustment value.

[0078] It should be noted that ΔT 线n and ΔT 非n are the preliminary temperature adjustment values under linear and non-linear relationship conditions, and are combined as ΔT during calculation n .

[0079] The technical solutions in the embodiments of the present application described above have at least the following technical effects or advantages:

[0080] By obtaining the maximum voltage difference and the minimum voltage difference of the temperature sensor in a reference temperature environment and setting multiple reference voltage difference measurement points, a basis for accurate calibration is provided. Using the internal reference voltage and the external calibration voltage, the preliminary temperature parameter and the standard temperature parameter are calculated respectively, effectively combining the characteristics of the temperature sensor itself and the calibration advantages of the external high-precision voltage. Further, by calculating the linear and non-linear relationships of each voltage difference with respect to the preliminary temperature parameter, not only the linear output characteristics of the temperature sensor are considered, but also the possible non-linear factors are concerned, improving the accuracy and comprehensiveness of the calibration. In particular, the least squares method is used to linearly fit the preliminary temperature adjustment value and the voltage difference to obtain a specific linear relationship formula. At the same time, for the part that cannot be fitted by the linear relationship formula, it is denoted as a non-linear relationship and processed separately, further ensuring the accuracy and reliability of the calibration. Finally, the target compensation temperature value required by the temperature sensor is calculated according to the preliminary temperature adjustment value, realizing the accurate calibration of the temperature sensor and significantly improving the accuracy and stability of temperature measurement.

[0081] Embodiment 2: In Embodiment 1, when calculating the target compensation temperature value of the temperature sensor, only the preliminary temperature adjustment value was considered, and the influence of time factors on the working state was not fully taken into account. In practical applications, the working performance of the temperature sensor changes over time, and this change may cause a difference between the preliminary temperature adjustment value and the theoretical value, that is, the time offset. Ignoring this factor will make the calculation of the target compensation temperature value inaccurate, thereby affecting the accuracy and stability of temperature control. Due to differences in factors such as the working time, standby time, and self-aging degree of different temperature sensors, the variation law and degree of their time offsets will also be different. In order to further refine and distinguish the calculation of the target compensation temperature value and obtain more accurate results, it is necessary to consider both the preliminary temperature adjustment value and the time offset, and establish a corresponding mathematical model for analysis. Therefore, in Embodiment 2, the concept of time offset is introduced, and a mathematical model of the preliminary temperature adjustment value and the working time is established through linear regression statistics to calculate the target compensation temperature value more accurately.

[0082] In some embodiments, considering the time offset, step S5, calculating the target compensation temperature value of the temperature sensor according to the preliminary temperature adjustment value, further includes:

[0083] S51, record the preliminary temperature adjustment value and the corresponding working time when the temperature sensor is working.

[0084] Specifically, when the temperature sensor outputs different voltage differences, record the preliminary temperature adjustment value and the corresponding working time regularly (such as every n hours).

[0085] S52, establish a mathematical model of the preliminary temperature adjustment value and the working time using linear regression statistics.

[0086] Among them, the mathematical model of the preliminary temperature adjustment value and time is ΔT n = f(t), where f(t) is a function of time t.

[0087] S53, based on the established mathematical model, analyze the variation law of the preliminary temperature adjustment value with time.

[0088] Among them, the variation law is that the preliminary temperature adjustment value gradually increases, decreases, or remains stable with the working time, etc.

[0089] Let the value of time t obtained from the mathematical model be T 理论 (t), and the time offset be ΔT(t), then the time offset calculation formula is: ΔT(t) = ΔT n - T 理论 (t). The formula is used to calculate the difference between the preliminary temperature adjustment value and the theoretical value under the actual working time, that is, the time offset.

[0090] S54. Calculate the target compensation temperature value according to the mathematical relationship between the preliminary temperature adjustment value and the time offset.

[0091] Among them, the formula for the target compensation temperature value is: T c (t) = ΔT n -ΔT(t). The formula is used to calculate the final temperature value after compensating for the time offset and the preliminary temperature adjustment value, that is, the target compensation temperature value.

[0092] The technical solutions in the embodiments of the present application at least have the following technical effects or advantages:

[0093] By carefully recording the preliminary temperature adjustment value and the corresponding working time of the temperature sensor during operation, and using the linear regression statistical method to establish a mathematical model between the two, the accuracy and reliability of temperature compensation are significantly improved. This solution not only considers the output characteristics of the temperature sensor itself, but also deeply analyzes its changing law over time, enabling the temperature compensation to dynamically adapt to the working state of the temperature sensor. By calculating the time offset, this solution can accurately capture the difference between the actual working time of the temperature sensor and the theoretical value, and then calculate a more accurate target compensation temperature value through a mathematical relationship. The implementation of this technical solution effectively improves the accuracy and stability of temperature control, providing strong technical support for the precise compensation of temperature sensors.

[0094] Embodiment 3: In Embodiment 1, although the temperature adjustment value of the temperature sensor has been preliminarily calibrated through a series of methods, in actual applications, the change of the temperature environment often has a non-linear impact on the performance of the temperature sensor, and this impact is not obvious in the linear fitting calibration. For calibrating the temperature sensor under non-linear relationships, especially in different temperature environments, the output characteristics of the temperature sensor will change significantly and unstably, resulting in a large deviation between the preliminary temperature adjustment value and the actual temperature. In addition, even in the same temperature environment, due to the non-linear characteristics of the temperature sensor itself, its output may also deviate from the ideal output temperature value. Therefore, in order to calibrate the temperature sensor more accurately and improve the measurement accuracy, it is necessary to consider the specific impact of the temperature environment on the non-linear adjustment temperature value. For this reason, in Embodiment 3, an environment adaptation factor is introduced. By determining the non-linear characteristics and trends, defining the temperature environment change factor, and calculating the influence coefficient of the temperature environment on the non-linear adjustment temperature value, the preliminary temperature adjustment value is corrected. At the same time, a mapping relationship and a calibration curve between the environmental parameters and the calibration parameters are established to more comprehensively consider the impact of the temperature environment on the performance of the temperature sensor and improve the accuracy and reliability of calibration.

[0095] In some embodiments, in step S45, the linear and non-linear relationships between the voltage difference and the preliminary temperature adjustment value are sorted out, and an environmental adaptation factor is introduced, including:

[0096] S451, after determining the non-linear characteristics and trends, adjust the reference temperature environment.

[0097] S452, define a temperature environment change factor to describe the influence of the temperature environment on the non-linearly adjusted temperature value.

[0098] Specifically, define the temperature environment change factor ΔT e , which represents the difference between the current temperature environment and the reference temperature environment, and can be a positive or negative value, depending on whether the current temperature is higher or lower than the reference temperature. This factor is used to quantify the specific influence of the temperature environment on the non-linearly adjusted temperature value.

[0099] S453, according to the temperature environment change factor and the preliminary temperature adjustment value, calculate the influence coefficient of the temperature environment on the non-linearly adjusted temperature value.

[0100] Specifically, through multiple experiments, determine the relationship between the temperature environment change factor ΔT e and the preliminary temperature adjustment value ΔT n . Based on this relationship, calculate an influence coefficient k, which represents the relative influence of the temperature environment change on the non-linearly adjusted temperature value. The calculation of k involves linear regression statistical methods.

[0101] S454, establish a mapping relationship between the environmental parameters and the calibration parameters under different temperature environments.

[0102] Specifically, under multiple different temperature environments, collect data on environmental parameters (temperature) and calibration parameters (voltage difference, preliminary temperature adjustment value), and use these data to establish a mapping relationship to describe the dependence relationship between the environmental parameters and the calibration parameters.

[0103] S455, use the calculated temperature adjustment influence coefficient to correct the non-linear preliminary temperature adjustment number.

[0104] Among them, the correction formula is: ΔT n =ΔT 非n +k*ΔT e , ΔT n is the preliminary temperature adjustment value, ΔT 非n is the preliminary temperature adjustment value under non-linear relationship conditions, k is the influence coefficient of the temperature environment on the non-linearly adjusted temperature value, and ΔT e is the temperature environment change factor, which represents the difference between the current temperature environment and the reference temperature environment.

[0105] S456. Establish a calibration curve using the temperature adjustment influence coefficient, voltage difference, preliminary temperature adjustment value, and the corrected temperature adjustment value.

[0106] The technical solutions in the embodiments of the present application at least have the following technical effects or advantages:

[0107] By comprehensively considering the non - linear characteristics of the voltage difference of the temperature sensor and the preliminary temperature adjustment value and the changes in the temperature environment, accurate calibration of the temperature sensor in a complex environment is achieved. The calibration accuracy and reliability are improved, making the output of the temperature sensor closer to the actual temperature value. At the same time, by introducing the temperature environment change factor and influence coefficient, the calibration process is refined, enhancing the adaptability and flexibility of calibration. In addition, establishing the mapping relationship between environmental parameters and calibration parameters and drawing the calibration curve greatly improves the calibration efficiency and accuracy.

[0108] Embodiment 4: In Embodiment 1, after preliminarily calculating the linear and non - linear relationships of each voltage difference with respect to the temperature parameter, simply distinguishing these two relationships is not sufficient to meet the requirements of high - precision calibration. The stability of the linear relationship and the characteristic changes of the non - linear relationship are crucial for the accuracy and reliability of the calibration logic. Therefore, in Embodiment 4, the characteristics of the linear and non - linear relationships are analyzed in detail, and corresponding thresholds are set to quantify these characteristics. Based on this, although a certain basis for calibration has been provided by distinguishing the linear and non - linear relationships, the fixed processing method and unified calibration logic may not fully adapt to the actual differences between different temperature sensors, resulting in limited calibration accuracy. To make the calibration results of the temperature sensor more reliable and accurate, the calibration logic is further limited and improved, introducing the segmented processing and early - point concepts in order to achieve higher calibration accuracy and practicality.

[0109] In some embodiments, in step S4, when calculating the linear and non - linear relationships of each voltage difference with respect to the preliminary temperature parameter, it further includes:

[0110] S4a. Analyze the characteristics of the calculated linear and non - linear relationships.

[0111] Specifically, for the linear relationship part, identify and quantify the variation rules of its slope (k) and intercept (b), and set the threshold for linear stability. For the non - linear relationship part, analyze its variation trends, such as characteristics like inflection points and saturation regions, and set the corresponding identification thresholds.

[0112] S4b. Segment the voltage difference measurement points according to the linear and non - linear characteristics.

[0113] Specifically, according to the threshold set in S4a, the voltage difference measurement points are segmented according to the stability of the linear relationship and the characteristic changes of the non-linear relationship. Each segment should have obvious linear or non-linear characteristics, and the specific range and characteristic description of the segment should be recorded.

[0114] In S4c, analyze the voltage difference measurement points within each segment to find the law of their change with temperature.

[0115] Specifically, use multiple experiments to find the accurate law of the voltage difference change with temperature within each segment. Record and analyze the accuracy and reliability of these laws to ensure their effective application during the calibration process.

[0116] In S4d, determine an advance point within each segment that represents the linear or non-linear characteristics of the segment.

[0117] Specifically, according to the voltage difference and temperature change law within the segment, determine one or more advance points that represent the characteristics of the segment. The selection of the advance point should be based on the extreme points, inflection points or specific temperature points of the linear or non-linear characteristics, etc., and record the specific position and characteristics of the advance point.

[0118] In S4e, establish the calibration logic of the temperature sensor according to the segmentation result and the advance point information.

[0119] Among them, the calibration logic includes how to identify the segment to which the current voltage difference belongs, and how to perform calibration according to the segment characteristics and the advance point.

[0120] In S4f, when the temperature sensor is powered on next time, it can perform real-time and rapid calibration according to the characteristic parameters of the ambient temperature and the voltage difference.

[0121] The technical solutions in the embodiments of the present application at least have the following technical effects or advantages:

[0122] By deeply analyzing the linear and non-linear relationship characteristics of the temperature sensor, setting corresponding thresholds for quantification, and combining segmentation processing and the concept of advance points, the calibration accuracy and reliability of the temperature sensor are greatly improved. This solution can not only more accurately identify the segment to which the current voltage difference belongs, but also perform refined calibration according to the segment characteristics and the advance point, thus effectively adapting to the actual differences between different temperature sensors, making the calibration result more reliable and accurate, and meeting the requirements of high-precision temperature measurement.

[0123] The above is only the preferred embodiment of the present invention and is not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A temperature sensor calibration method, characterized in that: include: S1, obtaining the maximum voltage difference and the minimum voltage difference output by the temperature sensor under the reference temperature environment, and setting the reference voltage difference measurement point; S2, receiving an internal reference voltage preset in the temperature sensor and an external calibration voltage connected externally; S3, calculating reference temperature parameters and standard temperature parameters of each voltage difference; S4, calculating the linear relationship and nonlinear relationship of each voltage difference with respect to the preliminary temperature adjustment value; S5, calculating a target compensation temperature value of the temperature sensor according to the preliminary temperature adjustment value.

2. The temperature sensor calibration method according to claim 2, characterized in that: The maximum voltage difference and the minimum voltage difference include: testing the temperature sensor in a reference temperature environment with a known and stable temperature, and recording the maximum voltage difference V_max and the minimum voltage difference V_min output by the temperature sensor at this temperature.

3. The temperature sensor calibration method according to claim 1, characterized in that: The step S4, calculating the linear relationship and the nonlinear relationship of each voltage difference with respect to the preliminary temperature adjustment value, comprises: S41, for each reference voltage difference measurement point, using the calculated reference temperature parameter and standard temperature parameter, calculate a preliminary temperature adjustment value; S42, collecting preliminary temperature adjustment values ​​and corresponding voltage differences of all reference voltage difference measurement points to form a data set; S43, using the least square method to perform linear fitting on the preliminary temperature adjustment value and the voltage difference to obtain a linear relationship; wherein the linear relationship is ΔT 线n =k*ΔV n +b, ΔV n is the voltage difference within the range of maximum voltage difference and minimum voltage difference, k is the linear slope, and b is the linear intercept; S44, for the voltage difference and the preliminary temperature adjustment value that cannot be fitted, record them as a nonlinear relationship; S45, sorting out the linear and nonlinear relationship between the voltage difference and the preliminary temperature adjustment value to form a calibration curve.

4. The temperature sensor calibration method according to claim 1, characterized in that: The step S5, calculating the target compensation temperature value of the temperature sensor according to the preliminary temperature adjustment value, specifically includes: S51, recording a preliminary temperature adjustment value and a corresponding working time when the temperature sensor is working; S52, using linear regression statistics to establish a mathematical model of the preliminary temperature adjustment value and the working time; wherein the mathematical model of the preliminary temperature adjustment value and the time is ΔT n =f(t), f(t) is a function of time t, ΔT n is the initial temperature adjustment value; S53, based on the established mathematical model, analyzing the law of change of the preliminary temperature adjustment value over time; the value of time t obtained by the mathematical model is T 理论 (t), the time offset is ΔT(t), then the time offset calculation formula is: ΔT(t) = ΔT n -T 理论 (t); S54, calculating and obtaining a target compensation temperature value according to a mathematical relationship between the preliminary temperature adjustment value and the time offset.

5. The temperature sensor calibration method according to claim 4, characterized in that: The target compensation temperature value in step S54 includes: the target compensation temperature value calculation formula is: c (t) = ΔT n -ΔT(t).

6. The temperature sensor calibration method according to claim 3, characterized in that: The step S45, arranging the linear and nonlinear relationship between the voltage difference and the preliminary temperature adjustment value, includes: S451, adjusting the reference temperature environment after determining the nonlinear characteristics and trends; S452, defining a temperature environment change factor to describe the influence of the temperature environment on the nonlinear adjustment temperature value; S453, calculating the influence coefficient of the temperature environment on the nonlinear adjustment temperature value according to the temperature environment change factor and the preliminary temperature adjustment value; S454, establishing a mapping relationship between environmental parameters and calibration parameters under different temperature environments; S455, using the calculated temperature adjustment influence coefficient, correcting the nonlinear preliminary temperature adjustment number; S456, establishing a calibration curve using the temperature adjustment influence coefficient, the voltage difference, the preliminary temperature adjustment value, and the corrected temperature adjustment value.

7. The temperature sensor calibration method according to claim 3, characterized in that: include: ΔT e is the temperature environment change factor, which indicates the difference between the current temperature environment and the reference temperature environment. It can be a positive or negative value, depending on whether the current temperature is higher or lower than the reference temperature. Through multiple tests, the relationship between the temperature environment change factor and the preliminary temperature adjustment value is determined, and an influence coefficient k is calculated based on this relationship.

8. The temperature sensor calibration method according to claim 6, characterized in that: The S455 includes: The correction formula is: ΔT n =ΔT 非n +k*ΔT e , ΔT n is the initial temperature adjustment value, ΔT 非n is the initial temperature adjustment value under the condition of nonlinear relationship, k is the influence coefficient of temperature environment on nonlinear adjustment temperature value, ΔT e is the temperature environment variation factor.

9. The temperature sensor calibration method according to claim 1, characterized in that: The S4 further includes: S4a, analyze the characteristics of the calculated linear and nonlinear relationships; S4b, segmenting the voltage difference measurement points according to the linear characteristics and the nonlinear characteristics; S4c, analyzing the voltage difference measurement points in each segment to find out the law of its change with temperature; S4d, determining an advance point representing the linear or nonlinear characteristics of the segment in each segment; S4e, establishing a calibration logic of the temperature sensor according to the segmentation result and the advance point information; S4f, when the temperature sensor is powered on next time, it can be quickly calibrated in real time according to the characteristic parameters of the ambient temperature and the voltage difference.

10. The temperature sensor calibration method according to claim 1, characterized in that: include: The reference temperature parameter is the reference temperature parameter corresponding to each voltage difference. The reference temperature parameter is the same as the reference temperature value T p There is a positive correlation, the formula is: Vref(p) is the internal reference voltage, K p is the temperature coefficient of the internal reference voltage, μ p is the reference temperature parameter; standard temperature parameter and standard temperature value T s There is a positive correlation, the formula is: ΔV n is the voltage difference, Vref(s) is the external calibration voltage, K s is the temperature coefficient of the external calibration voltage, μ s is the standard temperature parameter; the initial temperature adjustment value is the standard temperature value minus the reference temperature value, the formula is ΔT n =|T s -T p |,ΔT 线n With ΔT 非n It is the preliminary temperature adjustment value under the conditions of linear relationship and nonlinear relationship, which is combined as ΔT in calculation. n .

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