An automatic test method for analog module accuracy

Abstract

The present invention relates to the technical field of analog module precision testing, and in particular, to an automatic testing method for analog module precision. The method comprises the following steps: preparing a precision source meter and an analog module to be tested, and setting a test environment; adopting a dual-channel adaptive step fusion algorithm, and calculating real-time voltage error and current error, and capturing the minimum resolution; performing multiple sampling at each step, and performing least square fitting on the precision source meter output and the measured average value to obtain a fitting curve; using multiple correction technology to perform temperature drift compensation and nonlinear correction on the measured voltage error and current error, and using a comprehensive evaluation algorithm to determine the measurement accuracy and minimum resolution of the analog module. The automatic testing method for analog module precision can dynamically optimize the measurement process and ensure the measurement accuracy under complex environmental conditions by adopting a dual-channel adaptive step fusion algorithm and using multiple correction technology.

Description

Technical Field

[0001] The invention relates to the technical field of analog quantity module precision testing, in particular to an analog quantity module precision automatic testing method. Background Art

[0002] An automatic test method for analog module accuracy aims to improve measurement accuracy and ensure the reliability of measurement results. It uses a dual-channel adaptive step fusion algorithm to bidirectionally control the dynamic adjustment of voltage and current steps, and uses multiple correction techniques to control the real-time adjustment of measurement errors and correction of environmental effects, so as to accurately capture the minimum resolution and comprehensively evaluate the performance of the measurement system.

[0003] The existing analog module accuracy test methods are usually difficult to stabilize the measurement accuracy under different environmental conditions. In addition, due to the measurement through only one path and the influence of ambient temperature changes and system nonlinear effects during the measurement process, the measurement accuracy result deviation will increase. In summary, an analog module accuracy automatic test method is provided. Summary of the invention

[0004] The purpose of the present invention is to provide an automatic testing method for the accuracy of an analog module to solve the problem raised in the above background technology that the measurement accuracy result deviation increases due to the influence of only one path measurement and the changes in ambient temperature and system nonlinear effects during the measurement process.

[0005] To achieve the above object, the present invention provides an automatic testing method for analog module accuracy, comprising the following steps:

[0006] S1. Prepare the precision source meter and the analog module to be tested, calibrate the precision source meter, and set up the test environment;

[0007] S2. Set the initial voltage and current step size, conduct preliminary tests, use a dual-channel adaptive step size fusion algorithm, and calculate the real-time voltage channel error and current channel error to capture the minimum resolution;

[0008] S3, perform multiple sampling at each step, perform least square fitting on the precision source meter output and the measured average value, and obtain the best fitting curve;

[0009] S4. Calculate the voltage channel error and the current channel error again and draw the error curve. Use the multiple correction technology to perform temperature drift compensation and nonlinear correction on the measured voltage channel error and current channel error. Use the comprehensive evaluation algorithm to determine the measurement accuracy and minimum resolution of the analog module.

[0010] As a further improvement of the technical solution, in S1, setting the test environment, the specific steps are as follows:

[0011] S1.1. Install precision temperature sensors in the test area to monitor the test environment temperature in real time and maintain the test environment temperature between 20 degrees Celsius and 25 degrees Celsius;

[0012] S1.2. Install humidity sensors in the test area to monitor the ambient humidity in real time and maintain the test ambient humidity between 40% and 60%;

[0013] S1.3. Isolate the test area from the external environment and use an anti-static workbench and shielding device;

[0014] S1.4. Check and manage the power supply in the test area and use UPS to provide power to the equipment.

[0015] As a further improvement of the technical solution, in S2, the dual-channel adaptive step fusion algorithm measures the voltage and current signals simultaneously, realizes dynamic adjustment of the step size and fusion of the two measurement results, captures the minimum resolution, and is used to measure the accuracy of the analog module. The specific steps are as follows:

[0016] S2.1, at each step, for the voltage input signal and current input signal , respectively measure the response voltage of the analog module and the response current ;

[0017] S2.2. Calculate the voltage channel error separately and current channel error ;

[0018] S2.3, according to the measured voltage channel error and current channel error , use the dual-channel adaptive step fusion algorithm to adjust the new voltage step and the new step size of the current ;

[0019] S2.4. When the voltage step and current step changes reach the minimum, record the minimum resolution of the voltage channel. and current channel minimum resolution , take the minimum resolution of the voltage channel and current channel minimum resolution The average , as the final measurement result.

[0020] As a further improvement of the technical solution, in S2.2, the voltage channel error is calculated and current channel error , the specific method is as follows:

[0021] ;

[0022] ;

[0023] in, is the voltage channel error; is the current channel error; is a voltage input signal; is the current input signal; To measure the response voltage of the analog module; The response current.

[0024] As a further improvement of the technical solution, in S2.3, a dual-channel adaptive step fusion algorithm is used to adjust the new voltage step size and the new step size of the current , the specific method is as follows:

[0025] ;

[0026] ;

[0027] in, It is Voltage step size under step size; It is Current step size under step size; It is Voltage step size under step size; It is Current step size under step size; is the voltage step adjustment coefficient, which is used to control the adjustment amplitude of the voltage step; is the current step adjustment coefficient, which is used to control the adjustment amplitude of the current step;

[0028] In S2.4, when the voltage step size and current step size change amount reach the minimum, the minimum resolution of the voltage channel is taken. and current channel minimum resolution The average , the specific method is as follows:

[0029] ;

[0030] in, Minimum resolution of voltage channel and current channel minimum resolution The average value of .

[0031] As a further improvement of the technical solution, in S3, multiple sampling is performed at each step length, and the output of the precision source meter and the measured average value are least square fitted to obtain the best fitting curve. The specific steps are as follows:

[0032] S3.1. At each step The voltage and current response of the analog module are measured multiple times, and the voltage output of the precision source meter is recorded. and current , and the corresponding analog module response voltage and the response current of the analog module ;

[0033] S3.2, at each step At the analog module, the response voltage and the response current of the analog module Perform an average calculation and record the average response voltage at each step and the average response current ;

[0034] ;

[0035] ;

[0036] Among them, the is the number of sampling times at this step length; For the step length The subsampling;

[0037] S3.3. Find the output voltage of the precision source meter by fitting the curve and current The average response voltage is measured and the average response current The best matching relationship between them;

[0038] S3.4, fitting the voltage and current respectively, and constructing a fitting function;

[0039] S3.5, using the least squares method to calculate the fitting parameters and minimize the sum of squared errors between the fitting curve and the actual measured data;

[0040] S3.6. Use the fitting parameters to draw a fitting curve.

[0041] As a further improvement of the technical solution, in S3.4, the voltage and current are fitted respectively to construct a fitting function, which is specifically as follows:

[0042] ;

[0043] ;

[0044] in, is the slope of the voltage fitting curve; is the intercept of the voltage fitting curve; is the slope of the current fitting curve; is the intercept of the current fitting curve;

[0045] The least square method is used in S3.5 to calculate the fitting parameters and minimize the voltage residual sum of squares between the fitting curve and the actual measurement data. and the current residual sum of squares ;

[0046] ;

[0047] ;

[0048] in, is the voltage residual sum of squares, which represents the total sum of squares of errors between the fitted curve and the actual voltage measurement average; is the sum of squares of the current residual, which represents the sum of squares of the total error between the fitting curve and the actual current measurement average; is the slope of the voltage fitting curve; is the intercept of the voltage fitting curve; is the slope of the current fitting curve; is the intercept of the current fitting curve; is the step length; is the total number of steps.

[0049] As a further improvement of the present technical solution, in S4, the voltage channel error and the current channel error are calculated again and an error curve is drawn, a multiple correction technique is used to perform temperature drift compensation and nonlinear correction on the measured voltage channel error and current channel error, and a comprehensive evaluation algorithm is used to determine the measurement accuracy and minimum resolution of the analog module. The specific method is as follows:

[0050] S4.1. After fitting and preliminary correction, recalculate the voltage channel error and current channel error ;

[0051] S4.2. Use the recalculated voltage channel error and current channel error , respectively draw the error curves of the voltage and current channels, with the horizontal axis being the step length , the vertical axis is the error value and ;

[0052] S4.3. During the test, use multiple correction techniques to compensate for the temperature drift of the measured voltage channel error and current channel error, and record the current ambient temperature. , the compensated voltage measurement value and current measurement Replace the original response voltage and the response current , update voltage channel error and current channel error ;

[0053] S4.4. Update voltage channel error using quadratic polynomial and current channel error Perform nonlinear correction and convert the corrected voltage measurement value and current measurement Instead of the compensated voltage measurement and current measurement , update the final voltage channel error and current channel error ;

[0054] S4.5. Use the comprehensive evaluation algorithm to determine the measurement accuracy and minimum resolution and calculate the corrected voltage channel error and current channel error Standard Deviation and ;

[0055] S4.6. Based on the calibrated error curve, observe the small fluctuations in the error curve and detect the minimum signal change, which is the minimum resolution of the analog module.

[0056] As a further improvement of the technical solution, in S4.1, the voltage channel error is recalculated and current channel error , the specific method is as follows:

[0057] ;

[0058] ;

[0059] In S4.3, multiple correction techniques are used to compensate for temperature drift of the measured voltage channel error and current channel error, and the current ambient temperature is recorded. , the compensated voltage measurement value and current measurement Replace the original response voltage and the response current , update voltage channel error and current channel error , the specific method is as follows:

[0060] ;

[0061] ;

[0062] in, The ideal temperature for the environment; is the current ambient temperature; is the voltage temperature drift coefficient; is the current temperature drift coefficient;

[0063] ;

[0064] ;

[0065] in, is the voltage channel error after temperature drift compensation update; is the current channel error after temperature drift compensation update.

[0066] As a further improvement of the technical solution, in S4.4, a quadratic polynomial is used to update the voltage channel error and current channel error Perform nonlinear correction and convert the corrected voltage measurement value and current measurement Instead of the compensated voltage measurement and current measurement , update the final voltage channel error and current channel error , the specific method is as follows:

[0067] ;

[0068] ;

[0069] in, is the voltage measurement value after nonlinear correction; is the current measurement value after nonlinear correction; is the nonlinear correction coefficient of the voltage channel; is the nonlinear correction coefficient of the voltage channel;

[0070] ;

[0071] ;

[0072] in, is the voltage channel error after nonlinear correction and update; is the current channel error after nonlinear correction and update;

[0073] In S4.5, a comprehensive evaluation algorithm is used to determine the measurement accuracy and minimum resolution, and the corrected voltage channel error is calculated. and current channel error Standard Deviation and , the specific method is as follows:

[0074] ;

[0075] ;

[0076] in, is the standard deviation of the voltage measurement error; is the standard deviation of the current measurement error; is the total number of steps.

[0077] Compared with the prior art, the present invention has the following beneficial effects:

[0078] 1. In the automatic test method for the accuracy of analog modules, the voltage and current signals are measured simultaneously by using a dual-channel adaptive step fusion algorithm, and the bidirectional errors of the real-time voltage channel error and the current channel error are calculated. The measurement step size is adjusted to accurately capture the minimum resolution of the analog module, ensuring that high-precision measurement results are maintained under different measurement conditions.

[0079] 2. In the automatic test method for the accuracy of analog modules, multiple correction technologies, including temperature drift compensation and nonlinear correction, are used to achieve stable measurement accuracy under various environmental influences, reduce the impact of temperature changes and system nonlinear effects on measurement results, and thus improve the final measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Figure 1 The figure is a flow chart of the overall method of the present invention. DETAILED DESCRIPTION

[0081] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0082] Example:

[0083] See also Figure 1As shown, this embodiment provides an automatic test method for analog module accuracy, comprising the following steps:

[0084] S1. Prepare the precision source meter and the analog module to be tested, calibrate the precision source meter, and set up the test environment;

[0085] In this embodiment S1, calibrating the precision source meter is used to verify and adjust the accuracy of the output signal of the precision source meter;

[0086] Set up the test environment. The specific steps are as follows:

[0087] S1.1. Install precision temperature sensors in the test area to monitor the test environment temperature in real time and maintain the test environment temperature between 20 degrees Celsius and 25 degrees Celsius;

[0088] S1.2. Install humidity sensors in the test area to monitor the ambient humidity in real time and maintain the test ambient humidity between 40% and 60%;

[0089] S1.3. Isolate the test area from the external environment and use an anti-static workbench and shielding device;

[0090] In this embodiment, an anti-static workbench is used to effectively prevent static electricity accumulation, protect sensitive analog modules and precision source meters, and ensure that the equipment is not affected by electrostatic discharge during the test process;

[0091] The purpose of using a shielding device is to block the electromagnetic interference of external electromagnetic signals, ensure the integrity and stability of the signal during the test, and avoid measurement errors caused by electromagnetic interference;

[0092] In this embodiment, the anti-static workbench uses the Desco 66472 anti-static workbench mat kit that meets the international anti-static standards; the shielding device uses the Fischbach EMC shielding curtain;

[0093] S1.4. Check and manage the power supply in the test area and use UPS to provide power to the equipment.

[0094] S2. Set the initial voltage and current step size, conduct preliminary tests, use a dual-channel adaptive step size fusion algorithm, and calculate the real-time voltage channel error and current channel error to capture the minimum resolution;

[0095] In the automatic test method of analog module accuracy, the dual-channel adaptive step fusion algorithm is used to calculate the voltage channel error and the current channel error in real time. The step size can be dynamically adjusted according to the current error situation to ensure that the minimum resolution of the analog module can be captured more accurately during the measurement process, thereby improving the measurement precision and accuracy.

[0096] The measurement results of voltage and current channels are usually affected by different noise and error sources. By integrating the measurement results of voltage and current channels, the random errors that may exist in a single channel can be eliminated, further improving the stability and accuracy of the measurement results.

[0097] Dual-channel measurement provides redundancy. Even if anomalies or interference occur in one channel, the data of the other channel can still provide a reference. Voltage and current signals may show different error characteristics in different situations. The dual-channel adaptive step fusion algorithm can find a balance between the two, avoiding excessive amplification of single channel errors, thereby obtaining a more reliable measurement result.

[0098] In this embodiment S2, the dual-channel adaptive step fusion algorithm measures the voltage and current signals simultaneously, realizes dynamic adjustment of the step size and fuses the two measurement results, captures the minimum resolution, and is used to measure the accuracy of the analog module. The specific steps are as follows:

[0099] S2.1, at each step, for the voltage input signal and current input signal , respectively measure the response voltage of the analog module and the response current ;

[0100] S2.2. Calculate the voltage channel error separately and current channel error ;

[0101] S2.3, according to the measured voltage channel error and current channel error , use the dual-channel adaptive step fusion algorithm to adjust the new voltage step and the new step size of the current ;

[0102] S2.4. When the voltage step and current step changes reach the minimum, record the minimum resolution of the voltage channel. and current channel minimum resolution , take the minimum resolution of the voltage channel and current channel minimum resolution The average , as the final measurement result.

[0103] In this embodiment S2.2, the voltage channel error is calculated and current channel error , the specific method is as follows:

[0104] ;

[0105] ;

[0106] in, is the voltage channel error; is the current channel error; is a voltage input signal; is the current input signal; To measure the response voltage of the analog module; In response to the current;

[0107] In this embodiment S2.3, a dual-channel adaptive step fusion algorithm is used to adjust the new voltage step size and the new step size of the current , the specific method is as follows:

[0108] ;

[0109] ;

[0110] in, It is Voltage step size under step size; It is Current step size under step size; It is Voltage step size under step size; It is Current step size under step size; is the voltage step adjustment coefficient, which is used to control the adjustment amplitude of the voltage step; is the current step adjustment coefficient, which is used to control the adjustment amplitude of the current step;

[0111] In this embodiment, the voltage step adjustment coefficient is set 0.05, current step adjustment coefficient is 0.05. In the actual measurement process, it is necessary to monitor the step size change after each adjustment to ensure that the system gradually converges to the minimum resolution within a reasonable range. If the system shows too fast step size change, the voltage step size adjustment system and the current step size adjustment coefficient can be appropriately reduced. If the system converges too slowly, the voltage step size adjustment system and the current step size adjustment coefficient can be appropriately increased. and The range is between 0.01 and 0.1, and the specific value is determined through experimental adjustment;

[0112] In this embodiment S2.4, when the voltage step size and current step size change amount reach the minimum, the minimum resolution of the voltage channel is taken and current channel minimum resolution The average , the specific method is as follows:

[0113] ;

[0114] in, Minimum resolution of voltage channel and current channel minimum resolution The average value of .

[0115] S3, perform multiple sampling at each step, perform least square fitting on the precision source meter output and the measured average value, and obtain the best fitting curve;

[0116] The best fitting curve is obtained by using the least squares fitting method. By minimizing the sum of squares of errors between the measured value and the fitting curve, the mathematical model that best reflects the overall trend of the data can be found, effectively reducing the impact of random errors, so that the fitting curve can more accurately describe the relationship between the output of the precision source meter and the measured average value, thereby improving the accuracy and consistency of the measured data.

[0117] In this embodiment S3, multiple sampling is performed at each step length, and the precision source meter output and the measured average value are least square fitted to obtain the best fitting curve. The specific steps are as follows:

[0118] S3.1. At each step The voltage and current response of the analog module are measured multiple times, and the voltage output of the precision source meter is recorded. and current , and the corresponding analog module response voltage and the response current of the analog module ;

[0119] S3.2, at each step At the analog module, the response voltage and the response current of the analog module Perform an average calculation and record the average response voltage at each step and the average response current ;

[0120] ;

[0121] ;

[0122] Among them, the is the number of sampling times at this step length; For the step length The subsampling;

[0123] S3.3. Find the output voltage of the precision source meter by fitting the curve and current The average response voltage is measured and the average response current The best matching relationship between them;

[0124] S3.4, fitting the voltage and current respectively, and constructing a fitting function;

[0125] S3.5, using the least squares method to calculate the fitting parameters and minimize the sum of squared errors between the fitting curve and the actual measured data;

[0126] S3.6, draw a fitting curve using the fitting parameters;

[0127] In this embodiment S3.4, the voltage and current are fitted respectively to construct a fitting function, which is as follows:

[0128] ;

[0129] ;

[0130] in, is the slope of the voltage fitting curve; is the intercept of the voltage fitting curve; is the slope of the current fitting curve; is the intercept of the current fitting curve;

[0131] In this embodiment S3.5, the least square method is used to calculate the fitting parameters and minimize the voltage residual sum of squares between the fitting curve and the actual measurement data. and the current residual sum of squares ;

[0132] ;

[0133] ;

[0134] in, is the voltage residual sum of squares, which represents the total sum of squares of errors between the fitted curve and the actual voltage measurement average; is the sum of squares of the current residual, which represents the sum of squares of the total error between the fitting curve and the actual current measurement average; is the slope of the voltage fitting curve; is the intercept of the voltage fitting curve; is the slope of the current fitting curve; is the intercept of the current fitting curve; is the step length; is the total number of steps.

[0135] S4. Calculate the voltage channel error and the current channel error again and draw an error curve, use a multiple correction technique to perform temperature drift compensation and nonlinear correction on the measured voltage channel error and current channel error, and use a comprehensive evaluation algorithm to determine the measurement accuracy and minimum resolution of the analog module;

[0136] The benefit of using multiple correction technology to perform temperature drift compensation and nonlinear correction on the measured voltage channel error and current channel error is that it can reduce the measurement error caused by ambient temperature changes and system nonlinear effects, and improve the accuracy and stability of the measurement results. Temperature drift compensation can correct the measurement deviation caused by temperature changes and ensure the consistency of measurement accuracy under different temperature conditions; nonlinear correction can correct the nonlinear deviation that is not captured in the measurement system, making the measured value closer to the true value;

[0137] In this embodiment S4, the voltage channel error and the current channel error are calculated again and the error curve is drawn. The temperature drift compensation and nonlinear correction are performed on the measured voltage channel error and the current channel error using a multiple correction technique. The measurement accuracy and minimum resolution of the analog module are determined using a comprehensive evaluation algorithm. The specific method is as follows:

[0138] S4.1. After fitting and preliminary correction, recalculate the voltage channel error and current channel error ;

[0139] S4.2. Use the recalculated voltage channel error and current channel error , respectively draw the error curves of the voltage and current channels, with the horizontal axis being the step length , the vertical axis is the error value and ;

[0140] S4.3. During the test, use multiple correction techniques to compensate for the temperature drift of the measured voltage channel error and current channel error, and record the current ambient temperature. , the compensated voltage measurement value and current measurement Replace the original response voltage and the response current , update voltage channel error and current channel error ;

[0141] S4.4. Update voltage channel error using quadratic polynomial and current channel error Perform nonlinear correction and convert the corrected voltage measurement value and current measurement Instead of the compensated voltage measurement and current measurement , update the final voltage channel error and current channel error ;

[0142] S4.5. Use the comprehensive evaluation algorithm to determine the measurement accuracy and minimum resolution and calculate the corrected voltage channel error and current channel error Standard Deviation and ;

[0143] S4.6. According to the corrected error curve, observe the small fluctuations in the error curve and detect the minimum signal change, which is the minimum resolution of the analog module;

[0144] In S4.1 of this embodiment, the voltage channel error is recalculated and current channel error , the specific method is as follows:

[0145] ;

[0146] ;

[0147] In this embodiment S4.3, multiple correction techniques are used to perform temperature drift compensation on the measured voltage channel error and current channel error, and the current ambient temperature is recorded. , the compensated voltage measurement value and current measurement Replace the original response voltage and the response current , update voltage channel error and current channel error , the specific method is as follows:

[0148] ;

[0149] ;

[0150] in, The ideal temperature for the environment; is the current ambient temperature; is the voltage temperature drift coefficient; is the current temperature drift coefficient;

[0151] ;

[0152] ;

[0153] in, is the voltage channel error after temperature drift compensation update; is the current channel error after temperature drift compensation update.

[0154] In this embodiment S4.4, a quadratic polynomial is used to update the voltage channel error and current channel error Perform nonlinear correction and convert the corrected voltage measurement value and current measurement Instead of the compensated voltage measurement and current measurement , update the final voltage channel error and current channel error , the specific method is as follows:

[0155] ;

[0156] ;

[0157] in, is the voltage measurement value after nonlinear correction; is the current measurement value after nonlinear correction; is the nonlinear correction coefficient of the voltage channel; is the nonlinear correction coefficient of the voltage channel;

[0158] ;

[0159] ;

[0160] in, is the voltage channel error after nonlinear correction and update; is the current channel error after nonlinear correction and update;

[0161] In this embodiment S4.5, a comprehensive evaluation algorithm is used to determine the measurement accuracy and minimum resolution, and the corrected voltage channel error is calculated. and current channel error Standard Deviation and , the specific method is as follows:

[0162] ;

[0163] ;

[0164] in, is the standard deviation of the voltage measurement error; is the standard deviation of the current measurement error; is the total number of steps;

[0165] Corrected voltage channel error and current channel error Standard Deviation and , respectively represent the distribution range of voltage and current measurement errors. A smaller standard deviation means that the deviation between the measured value and the fitted value is smaller, indicating that the measurement system has higher accuracy and consistency;

[0166] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and the above embodiments and descriptions are only preferred examples of the present invention, and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. An automatic test method for analog module accuracy, characterized in that: The following steps are involved: S1. Prepare the precision source meter and the analog module to be tested, calibrate the precision source meter, and set up the test environment; S2. Set the initial voltage and current step size, conduct preliminary testing, and use a dual-channel adaptive step size fusion algorithm to calculate the real-time voltage channel error and current channel error to capture the minimum resolution. S3, perform multiple sampling at each step, perform least square fitting on the precision source meter output and the measured average value, and obtain the best fitting curve; S4. Calculate the voltage channel error and the current channel error again and draw an error curve, use a multiple correction technique to perform temperature drift compensation and nonlinear correction on the measured voltage channel error and current channel error, and use a comprehensive evaluation algorithm to determine the measurement accuracy and minimum resolution of the analog module; In S2, the dual-channel adaptive step fusion algorithm captures the minimum resolution by measuring the voltage and current signals simultaneously, which is used to measure the accuracy of the analog module. The specific steps are as follows: S2.1, at each step, for the voltage input signal and current input signal , respectively measure the response voltage of the analog module and the response current ; S2.

2. Calculate the voltage channel error separately and current channel error ; S2.3, according to the measured voltage channel error and current channel error , use the dual-channel adaptive step fusion algorithm to adjust the new voltage step and the new step size of the current ; S2.

4. When the voltage step and current step changes reach the minimum, record the minimum resolution of the voltage channel. and current channel minimum resolution , take the minimum resolution of the voltage channel and current channel minimum resolution The average , as the final measurement result; In S2.2, the voltage channel error is calculated and current channel error , the specific method is as follows: ； ； in, is the voltage channel error; is the current channel error; is the voltage input signal; is the current input signal; To measure the response voltage of the analog module; In response to the current; In S2.3, a dual-channel adaptive step fusion algorithm is used to adjust the new voltage step size. and the new step size of the current , the specific method is as follows: ； ； in, It is Voltage step size under step size; It is Current step size under step size; It is Voltage step size under step size; It is Current step size under step size; is the voltage step adjustment coefficient, which is used to control the adjustment amplitude of the voltage step; is the current step adjustment coefficient, which is used to control the adjustment amplitude of the current step; In S2.4, when the voltage step size and current step size change amount reach the minimum, the minimum resolution of the voltage channel is taken. and current channel minimum resolution The average , the specific method is as follows: ； in, Minimum resolution of voltage channel and current channel minimum resolution The average value of In S3, multiple sampling is performed at each step length, and the precision source meter output and the measured average value are fitted by least squares to obtain the best fitting curve. The specific steps are as follows: S3.

1. At each step The voltage and current response of the analog module are measured multiple times, and the voltage output of the precision source meter is recorded. and current , and the corresponding analog module response voltage and the response current of the analog module ; S3.2, at each step At the analog module, the response voltage and the response current of the analog module Perform an average calculation and record the average response voltage at each step and the average response current ; ； ； in, is the number of sampling times at this step length; For the step length The subsampling; S3.

3. Find the output voltage of the precision source meter by fitting the curve and current The average response voltage is measured and the average response current The best matching relationship between them; S3.4, fitting the voltage and current respectively, and constructing a fitting function; S3.5, using the least squares method to calculate the fitting parameters and minimize the sum of square errors between the fitting curve and the actual measured data; S3.6, draw a fitting curve using the fitting parameters; In S3.4, the voltage and current are fitted respectively to construct a fitting function, which is as follows: ； ； in, is the slope of the voltage fitting curve; is the intercept of the voltage fitting curve; is the slope of the current fitting curve; is the intercept of the current fitting curve; The least square method is used in S3.5 to calculate the fitting parameters and minimize the voltage residual sum of squares between the fitting curve and the actual measurement data. and the current residual sum of squares ; ； ； in, is the voltage residual sum of squares, which represents the total sum of squares of errors between the fitted curve and the actual voltage measurement average; is the sum of squares of the current residual, which represents the sum of squares of the total error between the fitted curve and the actual current measurement average; is the slope of the voltage fitting curve; is the intercept of the voltage fitting curve; is the slope of the current fitting curve; is the intercept of the current fitting curve; is the step length; is the total number of steps; In S4, the voltage channel error and the current channel error are calculated again and the error curve is drawn. The temperature drift compensation and nonlinear correction of the measured voltage channel error and the current channel error are performed using a multiple correction technique. The measurement accuracy and minimum resolution of the analog module are determined using a comprehensive evaluation algorithm. The specific method is as follows: S4.

1. After fitting and preliminary correction, recalculate the voltage channel error and current channel error ; S4.

2. Use the recalculated voltage channel error and current channel error , respectively draw the error curves of the voltage and current channels, with the horizontal axis being the step length , the vertical axis is the error value and ; S4.

3. During the test, use multiple correction techniques to compensate for the temperature drift of the measured voltage channel error and current channel error, and record the current ambient temperature. , the compensated voltage measurement value and current measurement Replace the original response voltage and the response current , update voltage channel error and current channel error ; S4.

4. Update voltage channel error using quadratic polynomial and current channel error Perform nonlinear correction and convert the corrected voltage measurement value and current measurement Instead of the compensated voltage measurement and current measurement , update the final voltage channel error and current channel error ; S4.

5. Use the comprehensive evaluation algorithm to determine the measurement accuracy and minimum resolution and calculate the corrected voltage channel error and current channel error Standard Deviation and ; S4.

6. According to the corrected error curve, observe the small fluctuations in the error curve and detect the minimum signal change, which is the minimum resolution of the analog module; In S4.1, the voltage channel error is recalculated. and current channel error , the specific method is as follows: ； ； In S4.3, multiple correction techniques are used to compensate for temperature drift of the measured voltage channel error and current channel error, and the current ambient temperature is recorded. , the compensated voltage measurement value and current measurement Replace the original response voltage and the response current , update voltage channel error and current channel error , the specific method is as follows: ； ； in, The ideal temperature for the environment; is the current ambient temperature; is the voltage temperature drift coefficient; is the current temperature drift coefficient; ； ； in, is the voltage channel error after temperature drift compensation update; is the current channel error after temperature drift compensation update; In S4.4, a quadratic polynomial is used to update the voltage channel error. and current channel error Perform nonlinear correction and convert the corrected voltage measurement value and current measurement Instead of the compensated voltage measurement and current measurement , update the final voltage channel error and current channel error , the specific method is as follows: ； ； in, is the voltage measurement value after nonlinear correction; is the current measurement value after nonlinear correction; is the nonlinear correction coefficient of the voltage channel; is the nonlinear correction coefficient of the voltage channel; ； ； in, is the voltage channel error after nonlinear correction and update; is the current channel error after nonlinear correction and update; In S4.5, a comprehensive evaluation algorithm is used to determine the measurement accuracy and minimum resolution, and the corrected voltage channel error is calculated. and current channel error Standard Deviation and , the specific method is as follows: ； ； in, is the standard deviation of the voltage measurement error; is the standard deviation of the current measurement error; is the total number of steps.

2. The method for automatically testing the accuracy of analog quantity modules according to claim 1, characterized in that: In S1, the test environment is set up, and the specific steps are as follows: S1.

1. Install precision temperature sensors in the test area to monitor the test environment temperature in real time and maintain the test environment temperature between 20 degrees Celsius and 25 degrees Celsius; S1.

2. Install humidity sensors in the test area to monitor the ambient humidity in real time and maintain the test ambient humidity between 40% and 60%; S1.

3. Isolate the test area from the external environment and use an anti-static workbench and shielding device; S1.

4. Check and manage the power supply in the test area and use UPS to provide power to the equipment.

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