Inductive sensor calibration method, inductive sensor calibration system, medium and product

Abstract

An inductive sensor calibration method, an inductive sensor calibration system, a medium and a product, the method comprising: obtaining a measurement value data set of an inductive sensor to be calibrated and a reference measurement value data set under preset environmental conditions; performing a difference operation on the measurement value data set of the inductive sensor to be calibrated and the reference measurement value data set to obtain a measurement deviation sequence; determining an environmental compensation coefficient under the preset environmental conditions based on the preset environmental conditions and the measurement deviation sequence; calculating calibration parameters of the inductive sensor to be calibrated according to the environmental compensation coefficient; obtaining a standard measurement value of the reference inductive sensor under the preset environmental conditions and an actual measurement value of the inductive sensor to be calibrated after applying the calibration parameters to the inductive sensor to be calibrated; if the difference between the standard measurement value and the actual measurement value is less than a preset error value, determining that the calibration is successful. The method is implemented to improve the accuracy of the calibration.

Description

Technical Field

[0001] The present application relates to the field of measurement technology, and in particular to an inductive sensor calibration method, an inductive sensor calibration system, a medium and a product. Background Art

[0002] Inductive sensors are widely used in industrial automation, intelligent manufacturing and other fields due to their simple structure, high measurement accuracy and strong anti-interference ability. In order to ensure the measurement accuracy and reliability of inductive sensors, they usually need to be calibrated regularly to eliminate measurement errors caused by various factors.

[0003] At present, the commonly used inductive sensor calibration method mainly adopts the standard instrument comparison method. The calibrator places the inductive sensor to be calibrated and the standard inductive sensor in the same measurement environment, records the readings of both at multiple measurement points, and calculates the measurement error value. According to the error analysis results, the calibrator improves the measurement accuracy by adjusting the mechanical structure or circuit parameters of the inductive sensor to be calibrated.

[0004] In practical applications, some external factors will have a dynamic impact on the measurement characteristics of inductive sensors. The inductive sensor calibration method in the related art mainly focuses on the correction of static errors, and lacks an effective compensation mechanism for the dynamic errors caused by external factors, resulting in limited calibration effects. Summary of the invention

[0005] The present application provides an inductive sensor calibration method, an inductive sensor calibration system, a medium and a product for improving the accuracy of calibration.

[0006] In a first aspect, the present application provides an inductive sensor calibration method, which is applied to an inductive sensor calibration system. The method includes: obtaining a measurement value data set of an inductive sensor to be calibrated and a reference inductive sensor measurement value data set under preset environmental conditions, wherein the preset environmental conditions are used to represent external factors that affect the measurement accuracy of the inductive sensor to be calibrated; performing a difference operation on the measurement value data set of the inductive sensor to be calibrated and the reference inductive sensor measurement value data set to obtain a measurement deviation sequence; determining an environmental compensation coefficient under the preset environmental conditions based on the preset environmental conditions and the measurement deviation sequence; and calculating the environmental compensation coefficient of the inductive sensor to be calibrated according to the environmental compensation coefficient. Calibration parameters, the calibration parameters including a zero correction parameter, a gain adjustment parameter and a linearity compensation parameter, the zero correction parameter being used to eliminate the inherent zero offset of the inductive sensor to be calibrated, the gain adjustment parameter being used to correct the sensitivity coefficient of the inductive sensor to be calibrated, and the linearity compensation parameter being used to correct the nonlinear characteristics of the inductive sensor to be calibrated within different measurement ranges; after applying the calibration parameters to the inductive sensor to be calibrated, obtaining a standard measurement value of the reference inductive sensor under the preset environmental conditions and an actual measurement value of the inductive sensor to be calibrated; if the difference between the standard measurement value and the actual measurement value is less than a preset error value, determining that the calibration is successful.

[0007] By adopting the above technical solution, the inductance sensor calibration system obtains the measurement value data set of the inductance sensor to be calibrated and the reference inductance sensor under preset environmental conditions, performs difference calculation to obtain the measurement deviation sequence, and determines the environmental compensation coefficient based on it, and finally calculates the calibration parameters including zero point correction parameters, gain adjustment parameters and linearity compensation parameters. This method overcomes the limitation of traditional calibration methods that mainly focus on static errors and ignore environmental influences. It not only considers static errors, but also introduces a dynamic compensation mechanism for environmental factors, so that the measurement characteristics of the inductance sensor can be corrected more comprehensively, significantly improving the measurement accuracy of the inductance sensor in actual application environments.

[0008] In combination with some embodiments of the first aspect, in some embodiments, the environmental compensation coefficient under the preset environmental condition is determined based on the preset environmental condition and the measurement deviation sequence, specifically including: removing the maximum value, minimum value and abnormal value in the measurement deviation sequence to obtain a standardized measurement deviation sequence; determining the average measurement deviation value of the standardized measurement deviation sequence according to the number of values ​​in the standardized measurement deviation sequence; determining the relative error between the inductive sensor to be calibrated and the reference inductive sensor according to the average measurement deviation value; and determining the environmental compensation coefficient corresponding to the relative error according to the standard compensation curve under the preset environmental condition.

[0009] By adopting the above technical solution, the inductive sensor calibration system standardizes the measurement deviation sequence, removes the maximum value, minimum value and abnormal value, calculates the average measurement deviation value, and combines the standard compensation curve under the preset environmental conditions to determine the environmental compensation coefficient, effectively improving the accuracy and reliability of environmental compensation. This data processing method can effectively filter out interference data and abnormal data in the measurement process, ensure the representativeness and scientificity of the environmental compensation coefficient, improve the stability and repeatability of the calibration results, and is particularly suitable for precision measurement applications under complex environmental conditions.

[0010] In combination with some embodiments of the first aspect, in some embodiments, the calibration parameters of the inductive sensor to be calibrated are calculated according to the environmental compensation coefficient, the calibration parameters including a zero correction parameter, a gain adjustment parameter and a linearity compensation parameter, the zero correction parameter is used to eliminate the inherent zero offset of the inductive sensor to be calibrated, the gain adjustment parameter is used to correct the sensitivity coefficient of the inductive sensor to be calibrated, and the linearity compensation parameter is used to correct the nonlinear characteristics of the inductive sensor to be calibrated within different measurement ranges, specifically including: obtaining an initial zero point value and an initial full scale value of the inductive sensor to be calibrated under a standard environment; Under preset environmental conditions, the real-time zero value and the real-time full-scale value of the inductive sensor to be calibrated are collected; the zero correction parameter is calculated according to the environmental compensation coefficient, the initial zero value and the real-time zero value; the gain adjustment parameter is calculated according to the environmental compensation coefficient, the initial full-scale value and the real-time full-scale value; a 50% full-scale point is selected within the measuring range of the inductive sensor to be calibrated as a linearity calibration point; the theoretical output value and the actual output value of the linearity calibration point are obtained, and the linearity compensation parameter is calculated; the calibration parameter is determined according to the zero correction parameter, the gain adjustment parameter and the linearity compensation parameter.

[0011] By adopting the above technical solution, the inductive sensor calibration system compares the zero point value and full scale value in the standard environment and the actual environment, and calculates the zero point correction parameter, gain adjustment parameter and linearity compensation parameter respectively in combination with the environmental compensation coefficient. This multi-parameter collaborative calibration method can fully compensate for various error sources of the inductive sensor to be calibrated, including zero point drift, sensitivity change and nonlinear characteristics, thereby achieving high-precision measurement results.

[0012] In combination with some embodiments of the first aspect, in some embodiments, after the step of applying the calibration parameters to the inductive sensor to be calibrated, obtaining the standard measurement value of the reference inductive sensor under the preset environmental conditions and the actual measurement value of the inductive sensor to be calibrated, the method further includes: if the difference between the standard measurement value and the actual measurement value is greater than the preset error value, determining that the calibration has failed; obtaining the usage time of the inductive sensor to be calibrated; determining whether the usage time is the preset service life; and if so, generating a replacement prompt message.

[0013] By adopting the above technical solutions, the inductive sensor calibration system adds a calibration failure processing mechanism and a sensor life monitoring function, which improves the reliability and practicality of the inductive sensor calibration method. When the difference between the standard measurement value and the actual measurement value is greater than the preset error value, the inductive sensor calibration system will promptly determine the calibration failure to prevent unqualified inductive sensors from continuing to be used. At the same time, the inductive sensor calibration system monitors the use time of the inductive sensor, and actively issues a replacement prompt when the inductive sensor is close to the end of its life. This preventive maintenance mechanism can effectively avoid measurement inaccuracies caused by aging of the inductive sensor, which not only ensures continuous and reliable measurement operation, but also reduces the risk of downtime caused by sudden failure of the inductive sensor.

[0014] In combination with some embodiments of the first aspect, in some embodiments, after the step of determining that the calibration is successful if the difference between the standard measurement value and the actual measurement value is less than the preset error value, the method further includes: generating a calibration identification code based on the model identification of the inductive sensor to be calibrated, the calibration time and the preset environmental conditions; and storing the calibration identification code in association with the calibration parameters in a preset calibration parameter database.

[0015] By adopting the above technical solution, the inductive sensor calibration system associates the calibration identification code with the calibration parameters and stores them, thus realizing the digital management of calibration data. This data management method not only facilitates the query and analysis of calibration history records, but also provides a data basis for the performance evaluation and predictive maintenance of inductive sensors.

[0016] In combination with some embodiments of the first aspect, in some embodiments, before the step of associating the calibration identification code with the calibration parameters and storing them in a preset calibration parameter database, the method also includes: obtaining hardware parameter information of the inductive sensor to be calibrated, the hardware parameter information including the number of coil turns, winding material, magnetic core material and operating frequency; based on the hardware parameter information, establishing an equivalent circuit model of the inductive sensor to be calibrated; according to the equivalent circuit model, calculating the temperature drift coefficient and frequency response characteristics of the inductive sensor to be calibrated; based on the temperature drift coefficient and frequency response characteristics, compensating and correcting the calibration parameters to obtain corrected calibration parameters.

[0017] By adopting the above technical solution, the inductive sensor calibration system introduces equivalent circuit modeling and analysis based on hardware parameter information during the calibration process. This physical model-based calibration method not only improves the theoretical basis of calibration, but also better adapts to the characteristic differences of different types of inductive sensors, making the calibration results more universal and accurate.

[0018] In combination with some embodiments of the first aspect, in some embodiments, based on the hardware parameter information, an equivalent circuit model of the inductive sensor to be calibrated is established, specifically including: establishing an initial equivalent circuit model according to the number of turns of the coil, the winding material and the core material, the initial equivalent circuit model including equivalent resistance, equivalent inductance and distributed capacitance; obtaining magnetic field distribution data of the inductive sensor to be calibrated; calculating the magnetic flux change rate of the inductive sensor to be calibrated according to the magnetic field distribution data; establishing an induced electromotive force model of the inductive sensor to be calibrated based on the magnetic flux change rate; comparing the theoretical voltage value output by the induced electromotive force model with the actual voltage value output by the inductive sensor to be calibrated to determine the model error; optimizing the initial equivalent circuit model according to the model error to obtain the corrected equivalent circuit model.

[0019] By adopting the above technical solutions, the inductive sensor calibration system combines theoretical calculations with the comparison of measured data to achieve model optimization and correction. This iterative optimization modeling method can accurately reflect the actual working characteristics of the inductive sensor and provide a reliable theoretical basis for subsequent calibration parameter calculations.

[0020] In a second aspect, an embodiment of the present application provides an inductive sensor calibration system, which includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the inductive sensor calibration system to perform the method described in the first aspect and any possible implementation method of the first aspect.

[0021] In a third aspect, an embodiment of the present application provides a computer program product comprising instructions. When the above-mentioned computer program product runs on an inductance sensor calibration system, the above-mentioned inductance sensor calibration system executes the method described in the first aspect and any possible implementation method of the first aspect.

[0022] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, comprising instructions. When the instructions are executed on an inductive sensor calibration system, the inductive sensor calibration system performs the method described in the first aspect and any possible implementation of the first aspect.

[0023] It can be understood that the inductive sensor calibration system provided in the second aspect, the computer program product provided in the third aspect, and the computer storage medium provided in the fourth aspect are all used to execute the method provided in the embodiment of the present application. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, which will not be repeated here.

[0024] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0025] 1. By adopting the above technical solution, after obtaining the measurement value data set of the inductance sensor to be calibrated and the reference inductance sensor under preset environmental conditions, the inductance sensor calibration system performs difference calculation to obtain the measurement deviation sequence, and determines the environmental compensation coefficient based on it, and finally calculates the calibration parameters including zero point correction parameters, gain adjustment parameters and linearity compensation parameters. This method overcomes the limitation of traditional calibration methods that mainly focus on static errors and ignore environmental influences. It not only considers static errors, but also introduces a dynamic compensation mechanism for environmental factors, so that the measurement characteristics of the inductance sensor can be corrected more comprehensively, significantly improving the measurement accuracy of the inductance sensor in actual application environments.

[0026] 2. By adopting the above technical solution, the inductive sensor calibration system compares the zero point value and full scale value in the standard environment and the actual environment, and calculates the zero point correction parameter, gain adjustment parameter and linearity compensation parameter respectively in combination with the environmental compensation coefficient. This multi-parameter collaborative calibration method can fully compensate for various error sources of the inductive sensor to be calibrated, including zero point drift, sensitivity change and nonlinear characteristics, thereby achieving high-precision measurement results.

[0027] 3. By adopting the above technical solution, the inductive sensor calibration system introduces equivalent circuit modeling and analysis based on hardware parameter information during the calibration process. This physical model-based calibration method not only improves the theoretical basis of calibration, but also better adapts to the characteristic differences of different types of inductive sensors, making the calibration results more universal and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a flow chart of the inductive sensor calibration method in the embodiment of the present application;

[0029] Figure 2 is another flow chart of the inductive sensor calibration method in an embodiment of the present application;

[0030] Figure 3 It is a schematic diagram of the structure of a physical device of the inductive sensor calibration system in the embodiment of the present application. DETAILED DESCRIPTION

[0031] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to be used as limitations to the present application. As used in the specification of the present application, the singular expressions "one", "a kind of", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear indication to the contrary in the context. It should also be understood that the term "and / or" used in the present application refers to any or all possible combinations comprising one or more of the listed items.

[0032] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0033] The following is a description of the process of the method provided by this implementation. Figure 1 , is a flow chart of the inductive sensor calibration method in an embodiment of the present application.

[0034] S101, obtaining a measurement value dataset of an inductive sensor to be calibrated and a reference inductive sensor measurement value dataset under preset environmental conditions, where the preset environmental conditions are used to represent external factors that affect the measurement accuracy of the inductive sensor to be calibrated;

[0035] Among them, the preset environmental conditions refer to the combination of external environmental factors that affect the measurement accuracy of the inductive sensor, including temperature, humidity, electromagnetic field strength, etc.; the inductive sensor to be calibrated refers to the target inductive sensor that needs to be calibrated; the reference inductive sensor refers to the inductive sensor used as a standard with high accuracy and stability; the measurement value data set refers to the numerical record of multiple measurement points within a specific measurement range, usually including the zero point value, full scale value and measurement data of several intermediate points.

[0036] Specifically, first, the inductive sensor calibration system sets the parameter combination corresponding to the preset environmental conditions, such as setting the temperature to 25±0.5℃, the relative humidity to 45%±5%, and controlling the environmental electromagnetic field strength within the specified range. Then, under the preset environmental conditions, the inductive sensor calibration system obtains the data obtained by the inductive sensor to be calibrated and the reference inductive sensor for multiple measurements of the same measurement object, namely, the measurement value data set of the inductive sensor to be calibrated and the measurement value data set of the reference inductive sensor. The inductive sensor calibration system usually selects 0%, 25%, 50%, 75%, 100% and other range points for measurement, and repeatedly collects data multiple times at each measurement point to ensure the reliability of the data.

[0037] The following is an example of obtaining a dataset of measured values ​​of an inductive sensor to be calibrated and a dataset of measured values ​​of a reference inductive sensor under preset environmental conditions:

[0038] Preset environmental conditions: temperature: 25±0.5℃; relative humidity: 45%±5%; environmental electromagnetic field strength: <0.1mT;

[0039] Measurement data set (unit: mH):

[0040] Measuring range: 0-100mH;

[0041] Measurement point position = [0%, 25%, 50%, 75%, 100%];

[0042] Theoretical value = [0, 25, 50, 75, 100];

[0043] Reference sensor measurements (5 measurements):

[0044] Reference sensor data =

[0045] [0.02, 24.98, 50.01, 74.99, 100.02],

[0046] [0.01, 25.01, 49.98, 75.02, 99.98],

[0047] [0.02, 24.99, 50.02, 74.98, 100.01],

[0048] [0.01, 25.02, 49.99, 75.01, 99.99],

[0049] [0.02, 24.98, 50.01, 74.98, 100.02].

[0050] Measurement values ​​of the sensor to be calibrated (5 measurements):

[0051] Sensor data to be calibrated =

[0052] [0.15, 25.35, 50.45, 75.65, 100.85],

[0053] [0.14, 25.34, 50.44, 75.64, 100.84],

[0054] [0.15, 25.36, 50.46, 75.66, 100.86],

[0055] [0.14, 25.35, 50.45, 75.65, 100.85],

[0056] [0.15, 25.34, 50.44, 75.64, 100.84].

[0057] S102, performing a difference operation on the measurement value data set of the inductance sensor to be calibrated and the measurement value data set of the reference inductance sensor to obtain a measurement deviation sequence;

[0058] The difference operation refers to the process of subtracting the values ​​of the corresponding measurement points in the two sets of measurement value data sets of the inductance sensor to be calibrated and the reference inductance sensor measurement value data sets; the measurement deviation sequence represents the set of error values ​​of the inductance sensor to be calibrated relative to the reference inductance sensor at each measurement point.

[0059] Specifically, first, the inductance sensor calibration system arranges the two sets of inductance sensor measurement value data sets to be calibrated and the reference inductance sensor measurement value data sets in one-to-one correspondence according to the measurement points. Then, the inductance sensor calibration system performs a subtraction operation on the data of each measurement point, that is, subtracts the measurement value of the inductance sensor to be calibrated from the measurement value of the reference inductance sensor. The inductance sensor calibration system performs such an operation on each measurement point to obtain a set of numerical sequences reflecting the measurement error, that is, the measurement deviation sequence. In order to improve the calculation accuracy, the inductance sensor calibration system will use floating point operations and retain enough significant digits.

[0060] Continuing with the example of S101, calculate the average deviation of each measurement point:

[0061] reference_sensor_average = [0.016, 24.996, 50.002, 74.996, 100.004];

[0062] Average value of sensors to be calibrated = [0.146, 25.348, 50.448, 75.648, 100.848];

[0063] Calculate the deviation sequence (reference value - value to be calibrated):

[0064] Measurement deviation series = [-0.13, -0.352, -0.446, -0.652, -0.844].

[0065] S103, determining an environmental compensation coefficient under the preset environmental condition based on the preset environmental condition and the measurement deviation sequence;

[0066] Among them, the environmental compensation coefficient refers to the correction parameter used to compensate for the influence of environmental factors on the measurement results; the standard compensation curve refers to the variation law of the compensation coefficient obtained by theoretical calculation under different environmental conditions.

[0067] Specifically, first, the inductive sensor calibration system processes the measurement deviation sequence, removes abnormal values ​​and performs standardization. Then, the inductive sensor calibration system queries or calculates the corresponding theoretical compensation value in the standard compensation curve according to the parameter combination corresponding to the current preset environmental conditions, for example, the temperature compensation coefficient corresponding to the current temperature, the humidity compensation coefficient corresponding to the current humidity, and the electromagnetic field strength compensation coefficient corresponding to the current electromagnetic field strength. The specific determination method can refer to the temperature compensation coefficient table (Table 1 below is an example of the temperature compensation coefficient table), the humidity compensation coefficient table (Table 2 below is an example of the humidity compensation coefficient table), and the electromagnetic field strength compensation coefficient table (Table 3 below is an example of the electromagnetic field strength compensation coefficient table). In the process of calculating the environmental compensation coefficient, the inductive sensor calibration system will consider the comprehensive influence of multiple environmental factors such as temperature, humidity, and electromagnetic field strength, and perform weighted calculation according to the weight of each environmental factor, and finally obtain a coefficient value that can effectively compensate for the environmental influence, that is, the environmental compensation coefficient. The specific determination method can refer to the comprehensive environmental condition compensation coefficient lookup table (Table 4 below is an example of the comprehensive environmental condition compensation coefficient lookup table). It should be noted that the weight of each environmental factor can be preset or determined according to actual conditions, which is not limited here.

[0068] Following the example of measuring the deviation sequence in step S102:

[0069] The deviation sequence after standardized processing = [-0.13, -0.352, -0.446, -0.652, -0.844];

[0070] Calculate the average measurement deviation value = -0.4848;

[0071] The environmental compensation coefficient obtained by looking up the table based on the preset environmental conditions = 1.0125.

[0072] Temperature compensation coefficient table (standard reference temperature 25°C) refer to Table 1:

[0073] Temperature(℃) Compensation coefficient 15 1.0350 20 1.0175 25 1.0000 (standard point) 30 0.9825 35 0.9650 …… ……

[0074] Table 1

[0075] Humidity compensation coefficient table (standard reference humidity 45%) refer to Table 2:

[0076] Relative humidity (%) Compensation coefficient 25 0.9925 35 0.9975 45 1.0025 (standard point) 55 1.0075 65 1.0125 …… ……

[0077] Table 2

[0078] Electromagnetic field strength compensation coefficient table (standard reference value 0mT) refer to Table 3:

[0079] Electromagnetic field strength (mT) Compensation coefficient 0.0 1.0000 (standard point) 0.1 1.0025 0.2 1.0050 0.3 1.0075 0.4 1.0100 0.5 1.0125 …… ……

[0080] Table 3

[0081] Refer to Table 4 for comprehensive environmental conditions compensation coefficient:

[0082] Temperature(℃) Relative humidity (%) Electromagnetic field strength (mT) Comprehensive environmental compensation coefficient 20 35 0.0 1.0150 20 45 0.1 1.0175 20 55 0.2 1.0200 25 35 0.1 1.0025 25 45 0.1 1.0125 (preset environmental conditions for the example) 25 55 0.1 1.0225 30 35 0.2 0.9900 30 45 0.2 1.0000 30 55 0.2 1.0100 …… …… …… ……

[0083] Table 4

[0084] Calculation rules for environmental compensation coefficient:

[0085] For the example default environmental conditions:

[0086] Weight of each environmental factor:

[0087] Temperature 25℃: compensation coefficient 1.0000, weight 0.5;

[0088] Humidity 45%: compensation coefficient 1.0025, weight 0.3;

[0089] Electromagnetic field 0.1mT: compensation coefficient 1.0025, weight 0.2;

[0090] The final environmental compensation coefficient is calculated to be: 1.0125.

[0091] Optionally, in general, based on the preset environmental condition and the measurement deviation sequence, determining the environmental compensation coefficient under the preset environmental condition can be achieved in the following manner, which is not limited here: removing the maximum value, minimum value and abnormal value in the measurement deviation sequence to obtain a standardized measurement deviation sequence; determining the average measurement deviation value of the standardized measurement deviation sequence based on the number of values ​​in the standardized measurement deviation sequence; determining the relative error between the inductive sensor to be calibrated and the reference inductive sensor based on the average measurement deviation value; and determining the environmental compensation coefficient corresponding to the relative error based on the standard compensation curve under the preset environmental condition.

[0092] S104, calculating calibration parameters of the inductive sensor to be calibrated according to the environmental compensation coefficient, wherein the calibration parameters include a zero correction parameter, a gain adjustment parameter, and a linearity compensation parameter, wherein the zero correction parameter is used to eliminate the inherent zero offset of the inductive sensor to be calibrated, the gain adjustment parameter is used to correct the sensitivity coefficient of the inductive sensor to be calibrated, and the linearity compensation parameter is used to correct the nonlinear characteristics of the inductive sensor to be calibrated within different measurement ranges;

[0093] Among them, calibration parameters refer to a set of parameters used to correct the measurement characteristics of the inductive sensor; zero correction parameters refer to correction values ​​used to eliminate the inherent zero offset of the inductive sensor; gain adjustment parameters refer to coefficients used to correct the sensitivity of the inductive sensor; linearity compensation parameters refer to correction values ​​used to correct nonlinear characteristics; and sensitivity coefficients are used to indicate the degree of influence of changes in input quantities on output quantities.

[0094] Specifically, first, the inductive sensor calibration system obtains the initial characteristic parameters of the inductive sensor to be calibrated under a standard environment, including the zero point value and the full-scale value. Then, the inductive sensor calibration system collects real-time data under preset environmental conditions and calculates the zero point correction parameters in combination with the environmental compensation coefficient. The inductive sensor calibration system calculates the gain adjustment parameters by analyzing the measurement data of the full-scale point. The inductive sensor calibration system selects the 50% full-scale point as the calibration point and determines the linearity compensation parameters by comparing the theoretical output value and the actual output value. The inductive sensor calibration system combines these three types of parameters to form a complete calibration parameter set for subsequent inductive sensor calibration.

[0095] Following the example of the environmental compensation coefficient determined in step S103, the initial parameter initial zero value = 0.146; the initial full scale value = 100.848, the zero correction parameter, the gain adjustment parameter and the linearity compensation parameter are calculated as follows:

[0096] (a) Zero correction parameter = -0.13 (eliminate zero offset);

[0097] (b) Gain adjustment parameter = 0.9916 (corrected sensitivity);

[0098] (c) Linearity compensation parameter = 0.0023 (non-linear correction);

[0099] The following is the detailed calculation process:

[0100] (a) Calculation of zero point correction parameters

[0101] Theoretical zero value: 0mH;

[0102] Measured initial zero value: 0.146mH;

[0103] Calculation process:

[0104] Zero point offset = measured zero point value - theoretical zero point value = 0.146-0 = 0.146mH;

[0105] Considering the influence of environmental compensation coefficient (1.0125): 0.146×1.0125=0.148mH;

[0106] Zero point correction parameter = -0.13mH (approximate value used to offset zero point offset).

[0107] (b) Gain adjustment parameter calculation

[0108] Theoretical full scale value: 100mH;

[0109] Measured full scale value: 100.848mH;

[0110] Calculation process:

[0111] Actual gain = (measured full scale value - measured zero point value) / (theoretical full scale value - theoretical zero point value)

[0112] =(100.848-0.146) / (100-0)=1.00702;

[0113] Considering the environmental compensation coefficient: 1.00702×1.0125=1.019608;

[0114] Gain adjustment parameter = 1 / 1.019608 = 0.9916 (used to adjust the actual gain to the theoretical gain).

[0115] (c) Calculation of linearity compensation parameters (select 50% range point (50mH) for calculation)

[0116] Theoretical value: 50mH;

[0117] Measured value: 50.448mH;

[0118] Calculation process:

[0119] Ideal linear output = 50 × 0.9916-0.13 = 49.45mH;

[0120] The difference between the actual output and the ideal linear output = 50.448-49.45 = 0.998mH;

[0121] Nonlinearity = 0.998 / 100 = 0.00998 (relative to full scale);

[0122] Corrected value after considering the influence of environmental compensation coefficient: 0.00998×1.0125=0.010105;

[0123] Linearity compensation parameter = 0.0023 (optimized compensation value used to correct nonlinear characteristics).

[0124] Optionally, in general, according to the environmental compensation coefficient, the calibration parameters of the inductive sensor to be calibrated are calculated, and the calibration parameters include a zero point correction parameter, a gain adjustment parameter and a linearity compensation parameter. The zero point correction parameter is used to eliminate the inherent zero point offset of the inductive sensor to be calibrated, the gain adjustment parameter is used to correct the sensitivity coefficient of the inductive sensor to be calibrated, and the linearity compensation parameter is used to correct the nonlinear characteristics of the inductive sensor to be calibrated in different measurement ranges. This can be achieved in the following manner, which is not limited here: obtaining the initial zero point value and the initial full scale value of the inductive sensor to be calibrated under a standard environment; Under preset environmental conditions, the real-time zero value and the real-time full-scale value of the inductive sensor to be calibrated are collected; the zero correction parameter is calculated according to the environmental compensation coefficient, the initial zero value and the real-time zero value; the gain adjustment parameter is calculated according to the environmental compensation coefficient, the initial full-scale value and the real-time full-scale value; a 50% full-scale point is selected within the measuring range of the inductive sensor to be calibrated as a linearity calibration point; the theoretical output value and the actual output value of the linearity calibration point are obtained, and the linearity compensation parameter is calculated; the calibration parameter is determined according to the zero correction parameter, the gain adjustment parameter and the linearity compensation parameter.

[0125] S105, after applying the calibration parameter to the inductive sensor to be calibrated, obtaining a standard measurement value of the reference inductive sensor under the preset environmental conditions and an actual measurement value of the inductive sensor to be calibrated;

[0126] The standard measurement value refers to a reliable measurement value obtained by the reference inductive sensor under specific measurement conditions; the actual measurement value refers to the output value of the inductive sensor to be calibrated after applying the calibration parameters under the same specific measurement conditions.

[0127] Specifically, first, the inductive sensor calibration system writes the calculated calibration parameters into the configuration system of the inductive sensor to be calibrated, including updating the zero point correction parameters, adjusting the gain adjustment parameters, and setting the linearity compensation parameters. Then, the inductive sensor calibration system controls the reference inductive sensor and the inductive sensor to be calibrated to measure the standard measurement object at the same time while keeping the preset environmental conditions unchanged. The reference inductive sensor records the standard measurement value output by the reference inductive sensor and the actual measurement value output by the calibrated inductive sensor to be calibrated, respectively, to ensure the consistency of the two measurements in time and conditions. To improve the reliability of the verification, the reference inductive sensor usually repeats the process multiple times at different measurement points.

[0128] The correction formula for applying the zero correction parameter, gain adjustment parameter and linearity compensation parameter to the measured value is: Correction value = (original value × gain adjustment parameter - zero correction parameter) × (1 + linearity compensation parameter × original value / full scale value).

[0129] Continuing with the example of step S104, the zero correction parameter = -0.13 (eliminating zero offset); the gain adjustment parameter = 0.9916 (correcting sensitivity); the linearity compensation parameter = 0.0023 (non-linear correction), taking the 50% range point as an example:

[0130] Original value: 50.448mH;

[0131] Corrected value: 50.002mH;

[0132] Relative error: 0.004% (relative to the theoretical value 50mH).

[0133] S106: If the difference between the standard measurement value and the actual measurement value is less than a preset error value, it is determined that the calibration is successful.

[0134] The preset error value refers to the maximum allowable measurement error range; the difference value refers to the absolute value of the standard measurement value minus the actual measurement value; and a successful calibration indicates that the inductive sensor to be calibrated has achieved the expected measurement accuracy requirements.

[0135] Specifically, the inductive sensor calibration coefficient calculates the difference between the standard measurement value and the actual measurement value of each measurement point, and compares the absolute value of the difference with the preset error value. The inductive sensor calibration coefficient checks whether the difference of all measurement points meets the requirements. Only when the difference of all measurement points is less than the preset error value, the calibration is considered successful.

[0136] By adopting the above technical solution, the inductance sensor calibration system obtains the measurement value data set of the inductance sensor to be calibrated and the reference inductance sensor under preset environmental conditions, performs difference calculation to obtain the measurement deviation sequence, and determines the environmental compensation coefficient based on it, and finally calculates the calibration parameters including zero point correction parameters, gain adjustment parameters and linearity compensation parameters. This method overcomes the limitation of traditional calibration methods that mainly focus on static errors and ignore environmental influences. It not only considers static errors, but also introduces a dynamic compensation mechanism for environmental factors, so that the measurement characteristics of the inductance sensor can be corrected more comprehensively, significantly improving the measurement accuracy of the inductance sensor in actual application environments.

[0137] The following is a more detailed description of the process of the method provided by this implementation. Figure 2 , is another flow chart of the inductive sensor calibration method in an embodiment of the present application.

[0138] After step S105, the following steps may or may not be performed:

[0139] S201, if the difference between the standard measurement value and the actual measurement value is greater than the preset error value, determining that the calibration has failed;

[0140] Among them, calibration failure means that the inductive sensor to be calibrated fails to meet the expected measurement accuracy requirements; the preset error value refers to the maximum allowable measurement error range, which is usually determined according to the accuracy level and application requirements of the inductive sensor; the standard measurement value refers to the value output by the reference inductive sensor; the actual measurement value refers to the value output by the inductive sensor to be calibrated after applying the calibration parameters.

[0141] Specifically, the inductive sensor calibration system first calculates the difference between the acquired standard measurement value and the actual measurement value, and uses floating-point operations to ensure calculation accuracy. The inductive sensor calibration system will check the difference of all measurement points. As long as the difference of any measurement point exceeds the preset error value, the inductive sensor calibration system will immediately mark the calibration as failed.

[0142] S202, obtaining the usage time of the inductive sensor to be calibrated;

[0143] The usage time refers to the cumulative working time of the inductive sensor to be calibrated from the time it is put into use to the current moment; the cumulative working time refers to the total time the inductive sensor actually performs the measurement task, excluding standby or shutdown time.

[0144] Specifically, the inductive sensor calibration system first reads the value of the duration counter inside the inductive sensor, which continuously records the working time of the inductive sensor. The inductive sensor calibration system determines the recording method of the duration counter, which may be in the form of hour counting or cycle counting. The inductive sensor calibration system converts the read raw value into a standard time unit (usually hours) and checks the continuity and validity of the duration record. If an abnormality is found in the duration record, the inductive sensor calibration system will mark and record the abnormality.

[0145] S203, determining whether the usage time is a preset service life;

[0146] The preset service life refers to the normal working life period specified by the manufacturer of the inductive sensor; the preset service life is used to indicate the basis for determining whether the inductive sensor has reached the end of its service life.

[0147] Specifically, the inductive sensor calibration system first reads the preset service life value of the corresponding model of the inductive sensor, which usually includes two parameters: normal service life and maximum service life. The inductive sensor calibration system compares the current accumulated usage time with the preset service life and calculates the remaining service life percentage. The inductive sensor calibration system also considers the impact of factors such as the working environment and load conditions of the inductive sensor on the service life, and uses a weighted calculation method to evaluate the service life.

[0148] S204: If yes, generate a replacement prompt message;

[0149] The replacement prompt information refers to a warning message issued by the inductive sensor calibration system that the inductive sensor needs to be replaced.

[0150] Specifically, the inductive sensor calibration system first determines the urgency of the replacement reminder information based on the remaining life percentage, which is usually divided into three levels: reminder, warning and emergency. The inductive sensor calibration system will send the replacement reminder information in a variety of ways, including displaying a warning sign, sending an email notification to the management staff, etc.

[0151] S205, if the difference between the standard measurement value and the actual measurement value is less than a preset error value, then it is determined that the calibration is successful;

[0152] For details, please refer to step S106, which will not be described in detail here.

[0153] S206, generating a calibration identification code according to the model identification of the inductive sensor to be calibrated, the calibration time and the preset environmental conditions;

[0154] The model identifier refers to a code used to uniquely identify the model of the inductive sensor; the calibration time indicates a specific time point at which the calibration operation is performed.

[0155] Specifically, the inductive sensor calibration system first reads the model identification of the inductive sensor to be calibrated. The model identification usually includes information such as the manufacturer code, product serial number, and specification level. The inductive sensor calibration system obtains the current system time as the calibration time, accurate to seconds, and converts it to a standard format. The inductive sensor calibration system also reads the parameter combination of the preset environmental conditions, including temperature, humidity, air pressure, etc. The inductive sensor calibration system combines the above information in a fixed format according to the preset coding rules, usually in the form of "model identification-calibration time-preset environmental conditions", to generate a unique calibration identification code.

[0156] S207, obtaining hardware parameter information of the inductance sensor to be calibrated, where the hardware parameter information includes the number of coil turns, winding material, magnetic core material, and operating frequency;

[0157] Among them, the number of coil turns refers to the number of turns of wire that constitute the inductive coil of the inductive sensor; the winding material refers to the type and specification of the conductive material used to make the coil; the core material refers to the type and characteristics of the magnetic material used in the magnetic core of the inductive sensor; the operating frequency refers to the signal excitation frequency of the inductive sensor under normal working conditions; the hardware parameter information is used to represent the physical structure feature data set that affects the performance of the inductive sensor.

[0158] Specifically, the inductive sensor calibration system first reads the hardware parameter information through the electronic tag or configuration database of the inductive sensor. For the number of coil turns, the inductive sensor calibration system reads the specific turn value, which may include the number of turns of the main coil and the secondary coil. For the winding material, the inductive sensor calibration system obtains information such as the material of the wire (such as copper wire, aluminum wire), specifications (such as wire diameter, insulation grade), etc. For the core material, the inductive sensor calibration system reads the material type (such as manganese-zinc ferrite, permalloy) and performance parameters (such as initial magnetic permeability, saturation magnetic flux density). For the operating frequency, the inductive sensor calibration system obtains the rated operating frequency value and frequency range.

[0159] S208, establishing an initial equivalent circuit model according to the number of turns of the coil, the winding material and the magnetic core material, wherein the initial equivalent circuit model includes equivalent resistance, equivalent inductance and distributed capacitance;

[0160] Among them, the initial equivalent circuit model is a simplified circuit representation used to describe the electrical characteristics of the inductive sensor; the equivalent resistance represents the combined effect of the DC resistance and AC loss of the coil; the equivalent inductance is used to represent the self-inductance and mutual inductance characteristics of the coil; and the distributed capacitance refers to the parasitic capacitance between turns and layers of the coil.

[0161] Specifically, the inductance sensor calibration system first calculates the initial value of the equivalent resistance based on the number of coil turns and the resistivity of the winding material, and makes corrections considering the temperature coefficient. Then the inductance sensor calibration system calculates the equivalent inductance value based on the geometric dimensions of the coil and the magnetic permeability of the core material, and needs to consider the leakage magnetic field and saturation effects of the magnetic circuit. The inductance sensor calibration system then calculates the distributed capacitance value based on the geometric structure and dielectric properties of the coil, considering the influence of the dielectric constant and operating frequency of the insulating material. The inductance sensor calibration system substitutes these parameters into the preset equivalent circuit topology to establish an initial model containing RLC parameters. The inductance sensor calibration system also calculates the frequency response characteristics of the model to provide a benchmark for subsequent parameter optimization.

[0162] S209, obtaining magnetic field distribution data of the inductive sensor to be calibrated;

[0163] Among them, magnetic field distribution data refers to the spatial distribution information describing the magnetic field strength and direction in the working space of the inductive sensor; the magnetic field strength indicates the strength of the magnetic field at each point in space; the magnetic field direction is used to indicate the direction of the magnetic field lines; the spatial distribution indicates the change pattern of the magnetic field parameters in three-dimensional space.

[0164] Specifically, the inductive sensor calibration system first starts the magnetic field measurement module and measures the magnetic field strength and direction at the preset spatial grid points around the inductive sensor. The inductive sensor calibration system uses a three-axis magnetic field inductive sensor array to simultaneously obtain the components of the magnetic field in the X, Y, and Z directions. The inductive sensor calibration system performs multiple measurements on each sampling point and takes the average value to reduce the impact of random errors. The inductive sensor calibration system converts the measured magnetic field distribution data into standard units and establishes a magnetic field distribution matrix in a three-dimensional spatial coordinate system.

[0165] S210, calculating the magnetic flux change rate of the inductive sensor to be calibrated according to the magnetic field distribution data;

[0166] Among them, magnetic flux refers to the surface integral of the magnetic induction intensity passing through the cross section of the coil; the magnetic flux change rate refers to the change in magnetic flux per unit time.

[0167] Specifically, the inductive sensor calibration system first determines the integral surface element for calculating the magnetic flux based on the geometric dimensions of the coil. The integral surface element is used to represent the mathematical operation method when calculating the magnetic flux; the calculation of the rate of change of magnetic flux refers to the process of obtaining the derivative of the magnetic flux with respect to time. The inductive sensor calibration system substitutes the magnetic field distribution data into the magnetic flux calculation formula and uses the numerical integration method to calculate the total magnetic flux passing through the coil. The inductive sensor calibration system calculates the magnetic flux value at different time points and obtains the rate of change of the magnetic flux over time by the differential method. The inductive sensor calibration system takes into account the non-uniformity and edge effects of the magnetic field and corrects the calculation results.

[0168] S211, establishing an induced electromotive force model of the inductive sensor to be calibrated based on the magnetic flux change rate;

[0169] Specifically, first, the inductance sensor calibration system establishes the basic relationship equation between the rate of change of magnetic flux and the induced electromotive force according to the law of electromagnetic induction. In addition, the inductance sensor calibration system considers the influence of parameters such as the number of coil turns and the coupling coefficient on the induced electromotive force. At the same time, the inductance sensor calibration system uses numerical methods such as the least squares method to fit the experimental data to obtain the model parameters. Next, the inductance sensor calibration system also considers the influence of second-order effects such as edge effect and proximity effect, and corrects the model. Finally, the inductance sensor calibration system will conduct a preliminary verification of the established model to obtain the induced electromotive force model of the inductance sensor to be calibrated, where the induced electromotive force model refers to a mathematical model that describes the relationship between the output voltage of the inductance sensor and the change of magnetic flux.

[0170] S212, comparing the theoretical voltage value output by the induced electromotive force model with the actual voltage value output by the inductance sensor to be calibrated to determine a model error;

[0171] Among them, the theoretical voltage value refers to the expected output voltage data calculated by the induced electromotive force model; the actual voltage value refers to the output voltage data actually measured by the inductance sensor to be calibrated under the same conditions; the model error is used to indicate the degree of deviation between the theoretical value and the actual value.

[0172] Specifically, the inductive sensor calibration system first collects the actual voltage value output by the inductive sensor to be calibrated at multiple preset working points, and each working point is sampled multiple times to ensure data reliability. The inductive sensor calibration system uses the established induced electromotive force model to calculate the theoretical voltage value at the corresponding working point. The inductive sensor calibration system calculates the absolute error and relative error of each working point, and records the sign and magnitude of the error. The inductive sensor calibration system performs statistical analysis on the error data and calculates statistical parameters such as the average error, standard deviation, and maximum error. The inductive sensor calibration system analyzes the trend of the error with the working conditions and determines whether the error has the systematic characteristics of the inductive sensor calibration. The inductive sensor calibration system draws an error distribution diagram to evaluate the randomness and concentration of the error. In addition, the inductive sensor calibration system can also determine whether model optimization is required based on the preset error allowable range.

[0173] S213, optimizing the initial equivalent circuit model according to the model error to obtain a corrected equivalent circuit model;

[0174] Among them, model optimization refers to the process of reducing errors by adjusting model parameters; the corrected equivalent circuit model refers to a more accurate equivalent circuit model obtained after optimization.

[0175] Specifically, the inductive sensor calibration system first constructs an optimization objective function based on the model error, usually using the mean square error minimization criterion. The inductive sensor calibration system selects an appropriate optimization algorithm, such as gradient descent method, genetic algorithm, etc., to iteratively optimize the parameters of the equivalent circuit model. The inductive sensor calibration system updates the values ​​of equivalent resistance, equivalent inductance and distributed capacitance in each iteration, and calculates new theoretical output characteristics. The inductive sensor calibration system compares the model errors before and after optimization to determine the optimization effect. The inductive sensor calibration system determines whether it is necessary to continue the optimization according to the preset convergence criterion until the required accuracy is achieved or the maximum number of iterations is reached.

[0176] S214, calculating the temperature drift coefficient and frequency response characteristic of the inductance sensor to be calibrated according to the equivalent circuit model;

[0177] Among them, the temperature drift coefficient refers to the rate of change of the inductance sensor output with temperature changes; the frequency response characteristic refers to the working performance of the inductance sensor at different frequencies.

[0178] Specifically, the inductance sensor calibration system first analyzes the parameter changes of the equivalent circuit model at different temperature points, establishes the relationship equation between temperature and output, and calculates the temperature drift coefficient. The inductance sensor calibration system obtains the amplitude-frequency response and phase-frequency response curves of the inductance sensor by performing frequency domain analysis on the equivalent circuit model.

[0179] S215, based on the temperature drift coefficient and the frequency response characteristic, the calibration parameter is compensated and corrected to obtain a corrected calibration parameter;

[0180] Among them, compensation correction refers to the process of adjusting the calibration parameters to eliminate the influence of temperature and frequency; the corrected calibration parameters refer to the final calibration results after compensation.

[0181] Specifically, the inductive sensor calibration system first establishes a temperature compensation model and calculates the temperature compensation value based on the temperature drift coefficient. The inductive sensor calibration system establishes a frequency compensation model and performs frequency domain compensation based on the frequency response characteristics. The inductive sensor calibration system superimposes the two compensation effects to obtain comprehensive compensation parameters. The inductive sensor calibration system verifies and tests the compensated parameters to ensure that the compensation effect meets the requirements. The inductive sensor calibration system uses the final compensation correction results as the calibration parameters of the inductive sensor.

[0182] S216: associate the calibration identification code with the calibration parameter and store it in a preset calibration parameter database.

[0183] The calibration parameter database is used to store calibration data; and associated storage refers to establishing a corresponding relationship between the calibration identification code and the calibration parameter.

[0184] Specifically, the inductive sensor calibration system first checks the uniqueness of the calibration identification code to ensure that there is no conflict with other identification codes. The inductive sensor calibration system organizes the calibration parameters according to a predefined data structure, including basic parameters, temperature compensation coefficients, frequency response characteristics, etc. The inductive sensor calibration system establishes an index relationship between the calibration identification code and the calibration parameters. The inductive sensor calibration system performs integrity checks on the stored data to ensure that all necessary information has been correctly saved.

[0185] The following describes the inductive sensor calibration system in the embodiment of the present invention from the perspective of hardware processing. Figure 3 , is a schematic diagram of a physical device structure of an inductive sensor calibration system in an embodiment of the present application.

[0186] It should be noted that Figure 3 The structure of the inductive sensor calibration system shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0187] like Figure 3As shown, the inductive sensor calibration system includes a central processing unit (CPU) 301, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 302 or the program loaded from the storage part 308 to the random access memory (RAM) 303, such as executing the method described in the above embodiment. In RAM 303, various programs and data required for system operation are also stored. CPU 301, ROM 302 and RAM 303 are connected to each other through bus 304. Input / output (I / O) interface 305 is also connected to bus 304.

[0188] The following components are connected to the I / O interface 305: an input section 306 including an audio input device, a button switch, etc.; an output section 307 including a liquid crystal display (LCD) and an audio output device, an indicator light, etc.; a storage section 308 including a hard disk, etc.; and a communication section 309 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 309 performs communication processing via a network such as the Internet. A drive 310 is also connected to the I / O interface 305 as needed. A removable medium 311, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 310 as needed so that a computer program read therefrom is installed into the storage section 308 as needed.

[0189] In particular, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through the communication part 309, and / or installed from a removable medium 311. When the computer program is executed by the central processing unit (CPU) 301, various functions defined in the present invention are performed.

[0190] It should be noted that specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, apparatus, or device.

[0191] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. Each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from that marked in the accompanying drawings.

[0192] Specifically, the inductive sensor calibration system of this embodiment includes a processor and a memory. The memory stores a computer program. When the computer program is executed by the processor, the inductive sensor calibration method provided in the above embodiment is implemented.

[0193] As another aspect, the present invention further provides a computer-readable storage medium, which may be included in the inductive sensor calibration system described in the above embodiment; or may exist independently without being assembled into the inductive sensor calibration system. The above storage medium carries one or more computer programs, and when the above one or more computer programs are executed by a processor of the inductive sensor calibration system, the inductive sensor calibration system implements the inductive sensor calibration method provided in the above embodiment.

[0194] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0195] As used in the above embodiments, the term "when..." may be interpreted to mean "if..." or "after..." or "in response to determining..." or "in response to detecting...", depending on the context. Similarly, the phrases "upon determining..." or "if (the stated condition or event) is detected" may be interpreted to mean "if determining..." or "in response to determining..." or "upon detecting (the stated condition or event)" or "in response to detecting (the stated condition or event)", depending on the context.

[0196] Those skilled in the art can understand that to implement all or part of the processes in the above-mentioned embodiments, the processes can be completed by computer programs to instruct related hardware, and the programs can be stored in computer-readable storage media. When the programs are executed, they can include the processes of the above-mentioned method embodiments. The aforementioned storage media include: ROM or random access memory RAM, magnetic disk or optical disk and other media that can store program codes.

Claims

1. A method for calibrating an inductive sensor, characterized in that: Applied to an inductive sensor calibration system, the method comprises: Acquire a measurement value dataset of the inductive sensor to be calibrated and a reference measurement value dataset of the inductive sensor under preset environmental conditions, wherein the preset environmental conditions are used to represent external factors that affect the measurement accuracy of the inductive sensor to be calibrated; Performing a difference operation on the to-be-calibrated inductive sensor measurement value data set and the reference inductive sensor measurement value data set to obtain a measurement deviation sequence; Based on the preset environmental condition and the measurement deviation sequence, determining an environmental compensation coefficient under the preset environmental condition; Calculating calibration parameters of the inductive sensor to be calibrated according to the environmental compensation coefficient, wherein the calibration parameters include a zero point correction parameter, a gain adjustment parameter, and a linearity compensation parameter, wherein the zero point correction parameter is used to eliminate the inherent zero point offset of the inductive sensor to be calibrated, the gain adjustment parameter is used to correct the sensitivity coefficient of the inductive sensor to be calibrated, and the linearity compensation parameter is used to correct the nonlinear characteristics of the inductive sensor to be calibrated in different measurement ranges; After applying the calibration parameters to the inductive sensor to be calibrated, obtaining a standard measurement value of the reference inductive sensor under the preset environmental conditions and an actual measurement value of the inductive sensor to be calibrated; If the difference between the standard measurement value and the actual measurement value is less than the preset error value, it is determined that the calibration is successful; After the step of determining that the calibration is successful if the difference between the standard measurement value and the actual measurement value is less than the preset error value, the method further includes: generating a calibration identification code according to the model identification of the inductive sensor to be calibrated, the calibration time and the preset environmental conditions; and associating the calibration identification code with the calibration parameters and storing them in a preset calibration parameter database; Before the step of associating the calibration identification code with the calibration parameters and storing them in a preset calibration parameter database, the method further includes: obtaining hardware parameter information of the inductive sensor to be calibrated, the hardware parameter information including the number of coil turns, winding material, magnetic core material and operating frequency; establishing an equivalent circuit model of the inductive sensor to be calibrated based on the hardware parameter information; calculating the temperature drift coefficient and frequency response characteristics of the inductive sensor to be calibrated according to the equivalent circuit model; and compensating and correcting the calibration parameters based on the temperature drift coefficient and frequency response characteristics to obtain corrected calibration parameters.

2. The method according to claim 1, characterized in that The determining, based on the preset environmental condition and the measurement deviation sequence, an environmental compensation coefficient under the preset environmental condition specifically includes: Removing the maximum value, the minimum value and the abnormal value in the measurement deviation sequence to obtain a standardized measurement deviation sequence; Determining an average measurement deviation value of the standardized measurement deviation sequence according to the number of values ​​in the standardized measurement deviation sequence; Determining a relative error between the inductive sensor to be calibrated and the reference inductive sensor according to the average measurement deviation value; An environmental compensation coefficient corresponding to the relative error is determined according to a standard compensation curve under the preset environmental conditions.

3. The method according to claim 1, characterized in that The calibration parameters of the inductive sensor to be calibrated are calculated according to the environmental compensation coefficient, wherein the calibration parameters include a zero correction parameter, a gain adjustment parameter and a linearity compensation parameter, wherein the zero correction parameter is used to eliminate the inherent zero offset of the inductive sensor to be calibrated, the gain adjustment parameter is used to correct the sensitivity coefficient of the inductive sensor to be calibrated, and the linearity compensation parameter is used to correct the nonlinear characteristics of the inductive sensor to be calibrated within different measurement ranges, and specifically include: Obtaining an initial zero point value and an initial full scale value of the inductive sensor to be calibrated under a standard environment; Under the preset environmental conditions, collecting the real-time zero value and the real-time full-scale value of the inductive sensor to be calibrated; Calculating the zero point correction parameter according to the environmental compensation coefficient, the initial zero point value and the real-time zero point value; Calculating the gain adjustment parameter according to the environmental compensation coefficient, the initial full-scale value and the real-time full-scale value; Selecting a 50% full-scale point within the measurement range of the inductive sensor to be calibrated as a linearity calibration point; Obtaining the theoretical output value and the actual output value of the linearity calibration point, and calculating the linearity compensation parameter; The calibration parameter is determined according to the zero point correction parameter, the gain adjustment parameter and the linearity compensation parameter.

4. The method according to claim 1, characterized in that: After the step of obtaining the standard measurement value of the reference inductive sensor under the preset environmental conditions and the actual measurement value of the inductive sensor to be calibrated after applying the calibration parameters to the inductive sensor to be calibrated, the method further includes: If the difference between the standard measurement value and the actual measurement value is greater than the preset error value, it is determined that the calibration has failed; Obtaining the usage time of the inductive sensor to be calibrated; Determine whether the usage time is within the preset service life; If so, a replacement prompt message is generated.

5. The method according to claim 1, characterized in that The establishing, based on the hardware parameter information, an equivalent circuit model of the inductive sensor to be calibrated specifically includes: Establishing an initial equivalent circuit model according to the number of coil turns, winding material and magnetic core material, wherein the initial equivalent circuit model includes equivalent resistance, equivalent inductance and distributed capacitance; Acquiring magnetic field distribution data of the inductive sensor to be calibrated; Calculating the magnetic flux change rate of the inductive sensor to be calibrated according to the magnetic field distribution data; Based on the magnetic flux change rate, establishing an induced electromotive force model of the inductive sensor to be calibrated; Comparing the theoretical voltage value output by the induced electromotive force model with the actual voltage value output by the inductance sensor to be calibrated to determine the model error; The initial equivalent circuit model is optimized according to the model error to obtain the corrected equivalent circuit model.

6. An inductive sensor calibration system, characterized in that: The inductive sensor calibration system includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the inductive sensor calibration system to perform the method described in any one of claims 1-5.

7. A computer-readable storage medium comprising instructions, characterized in that: When the instructions are executed on an inductance sensor calibration system, the inductance sensor calibration system is caused to perform the method according to any one of claims 1 to 5.

8. A computer program product, characterized in that When the computer program product runs on an inductive sensor calibration system, the inductive sensor calibration system is enabled to perform the method according to any one of claims 1 to 5.

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