A method for calibrating a single-phase electricity meter

Abstract

This invention relates to the field of measurement and calibration technology, specifically to a calibration and testing method for a single-phase electricity meter, comprising the following steps: acquiring a target current value and identifying output fluctuation trends, determining and adjusting to a stable output, extracting pulse sequences to analyze error response, locating error stability points and compressing test points, constructing a cycle response sequence chain, and shifting the cycle start time to generate a calibration test timing control instruction set. In this invention, by introducing a current trend stability identification and adjustment mechanism during signal output, the interference of initial fluctuations on measurement results is avoided. Through precise positioning of error response segments, highly sensitive identification of abnormal energy output segments is achieved. Representative test points are extracted based on error change trends, and time-shifting adjustments eliminate cycle overlap interference, achieving time-series coordination and unification among multiple test points, thus meeting the consistency and stability requirements of error calibration for electricity metering devices under operating conditions.

Description

Technical Field

[0001] This invention relates to the field of measurement and calibration technology, and in particular to a calibration and testing method for a single-phase electricity meter. Background Technology

[0002] The field of measurement calibration technology mainly involves the technical means and operational methods for accuracy assessment and error correction of various measuring equipment, instruments, and meters. This includes the establishment and transfer of reference instruments, error measurement and adjustment of the measured equipment, and recording and comparison of measurement data. This technical field covers the calibration operations of measuring equipment, including electrical parameter measuring instruments, thermal parameter measuring instruments, and length and angle measuring devices. It also involves verifying the performance indicators of the equipment according to industry standards to ensure the accuracy and traceability of their measurements. This field provides fundamental technical support in scenarios such as energy metering, manufacturing testing, and scientific research experiments.

[0003] The traditional calibration test method for single-phase electricity meters refers to the technical means of verifying the accuracy and checking the metering performance of single-phase electricity metering devices widely used in residential or industrial users. It addresses the issue of confirming and adjusting the error between the electricity displayed by the meter under rated operating conditions and the standard electricity value. Traditional calibration tests use a standard source of electrical parameters to provide specific voltage, current, and power factor signals. These signals are then connected to the single-phase electricity meter under test, and its count or pulse output is read and compared synchronously with a standard measuring device to analyze the metering error. The standard source signal is often used to simulate the load, and the meter's pulse output acquisition equipment is used for testing and verification. The magnitude of the error is determined based on the pulse count or time interval, and the metering characteristics are periodically calibrated.

[0004] Existing technologies rely on fixed electrical parameter standard sources to output voltage and current signals, without judging and adjusting for current fluctuation trends during the actual output process. This leads to error deviations when acquiring data during unstable signal phases. Furthermore, the lack of precise timing control in the response process to meter output pulses causes interference overlap between test points, making it difficult to accurately pinpoint the error to the specific operating point. Especially when load changes frequently or the meter response is sluggish, the pulse interval judgment deviation increases, affecting the repeatability and validity of test data. This hinders the formation of clear error boundary identification results and reduces the overall efficiency and accuracy of calibration testing. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and to propose a calibration and testing method for single-phase electricity meters.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a calibration and testing method for a single-phase electricity meter, comprising the following steps:

[0007] S1: Obtain the target value of the current set by the signal source. During the continuous output cycle under the standard voltage maintenance state, collect multiple continuous instantaneous current output values. Based on the sequential offset trend between sampling points, identify whether the output waveform has continuous rising or falling behavior, and obtain the stable current output segment identifier.

[0008] S2: Call the voltage, current and load status within the time period corresponding to the stable current output segment identifier, extract the energy pulse sequence and timestamp output by the single-phase meter, calculate the interval difference amplitude between adjacent pulses, and obtain the error response sensitive segment sequence.

[0009] S3: Based on the upper and lower boundary intervals of the error under the voltage and current combination conditions located by the error response sensitive segment sequence, select the error fluctuation center location as the representative test point to obtain the compressed test point list.

[0010] S4: Call the compressed test point list, extract the pulse response start time, voltage signal trigger time and current stable trigger start time of the test point, compare the voltage signal trigger time and current stable trigger start time with the pulse response time to obtain the test beat response sequence chain.

[0011] As a further embodiment of the present invention, the stable current output segment identifier includes current change trend characteristics, fluctuation direction consistency parameters, and output waveform stability index; the error response sensitive segment sequence includes power pulse interval variation amplitude, load fluctuation mapping relationship, and timing response sensitivity characteristics; the compressed test point list includes error center point location, voltage and current stable combination point location, and response behavior representative index; and the test beat response sequence chain includes beat trigger type marker, time sequence label, and response stage attribution information.

[0012] As a further aspect of the present invention, the step of obtaining the stable current output segment identifier specifically includes:

[0013] S111: Obtain the target value of the current set by the signal source, and according to the continuous output cycle under the standard voltage maintenance state, sequentially collect multiple continuous instantaneous current output values, record the sequential offset trend between data points, and identify whether the current shows a continuous rising or falling behavior by monitoring the changing trend of the data points, and obtain the fluctuation trend identification result.

[0014] S112: Based on the fluctuation trend identification result, compare the instantaneous current output value to determine whether there is a stable output state. If a consistent fluctuation behavior is detected, adjust the output waveform, perform quantitative analysis on the signal fluctuation within the segment, calculate the current stability metric value, and obtain the stable current output segment identifier.

[0015] As a further aspect of the present invention, the step of obtaining the error response sensitive segment sequence specifically comprises:

[0016] S211: Based on the voltage value, current value and load condition status within the time period corresponding to the stable current output segment identifier, call the power pulse sequence and the corresponding timestamp, compare the time difference of adjacent power pulses in turn, obtain the interval change between the time difference, determine whether the difference direction and change amplitude of the interval change in adjacent time periods continue to maintain the same change trend, and generate a time difference fluctuation trend value.

[0017] S212: Based on the time difference fluctuation trend value, sort the amplitude of fluctuation trend changes within the differentiated time period, call the pulse time difference value under the same trend in the time difference fluctuation trend value, calculate the response deviation value of the trend interval, and obtain the trend concentration offset based on the distribution density change of the response deviation value in the whole interval.

[0018] S213: Call the trend concentration offset, and based on the distribution difference of the trend concentration offset in the fluctuating and continuous regions, filter the stable time period before and after the trend concentration offset mutation point, and merge the intervals according to the consistency of trend direction and the fluctuation of offset to generate an error response sensitive segment sequence.

[0019] As a further aspect of the present invention, the step of obtaining the compressed test point list specifically includes:

[0020] S311: Based on the voltage and current combination operating point located by the error response sensitive section sequence, call the error upper and lower boundary interval data corresponding to the combination operating point, process the error upper and lower boundary values ​​of the point, and generate an error boundary interval width sequence.

[0021] S312: Call the error boundary interval width sequence, compare the difference between the widths of adjacent error boundary intervals in the combined points according to the changes in the width of the boundary intervals of adjacent combined working point points, determine whether there are segments where the changes in the width of the continuous error boundary intervals are lower than the error change threshold, and count the number of consecutive points in the segments and the corresponding interval range to obtain the error stable interval identification result.

[0022] S313: Based on the error stability interval identification result, calculate the error fluctuation measurement value in the error stability interval according to the upper and lower limit values ​​of the error boundary in the stability interval, select the corresponding voltage and current combination working condition points as representative test points according to the low value points of the error fluctuation measurement value inside the stability interval, and obtain the compressed representative test point list.

[0023] As a further aspect of the present invention, the step of obtaining the test beat response sequence chain specifically includes:

[0024] S411: Call the compressed list of representative test points, extract the pulse response start time, voltage signal trigger time and current stable trigger start time recorded in the test points, establish a time sequence arrangement index for each test point based on the extracted three time sequence data, filter the time position of the pulse response start time as the reference time point corresponding to the test point, and generate a pulse start reference time sequence.

[0025] S412: Based on the reference time point of the test point in the pulse start reference time sequence, compare the corresponding voltage signal trigger time and current stable trigger start time in turn to determine whether the pulse response start time is earlier than the voltage trigger time and the current trigger start time. If the determination result is yes, mark the test point as the main trigger point of the beat and generate the main trigger point marking sequence.

[0026] S413: Call the main trigger point marking sequence of the cycle, sort the corresponding main trigger points according to the time index in the pulse start reference time sequence, and postpone the remaining points marked by the voltage signal trigger time and the current stable trigger start time of the corresponding test point, identify the complete test cycle sequence relationship, and obtain the test cycle response sequence chain.

[0027] As a further aspect of the present invention, the method further includes step S5:

[0028] S5: Based on the triggering order and execution duration of the test points in the test beat response sequence chain, extract the beat interval segment of adjacent points, detect whether there is an overlap in the time coverage of the beat segment, and if there is an overlap, perform time shift processing on the start time of the test point beat to obtain the calibration test timing control instruction set;

[0029] The calibration test timing control instruction set includes clock synchronization strategy parameters, time shift compensation values, and conflict section adjustment results.

[0030] As a further aspect of the present invention, the step of obtaining the calibration test timing control instruction set specifically includes:

[0031] S511: Based on the test point triggering order and corresponding execution duration in the test beat response sequence chain, extract the pulse start time of two adjacent test points and the sum of the start time and duration of the test points, calculate the time difference between the two, and determine whether there is a segment overlap based on the difference, and generate a beat time cross-identification segment.

[0032] S512: Call the test point data with crossover behavior in the beat time crossover identification segment, and perform equal time interval time shift processing on the pulse start time of the test points whose start time is earlier than the point but whose duration covers the period before the start, to obtain the calibration test timing control instruction set.

[0033] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0034] In this invention, a current trend stability identification and adjustment mechanism is introduced during the signal output process to avoid interference from initial fluctuations on the measurement results. Precise positioning of the error response segment enables highly sensitive identification of abnormal power output segments. Representative test points are extracted by combining error change trends, significantly compressing the test point scale while preserving the error characteristic distribution. A beat response sequence chain is established by comparing trigger timing differences, and further, beat overlap interference is eliminated through time-based adjustments. This achieves time-series coordination and unification among multiple test points, improving the overall measurement process's error response accuracy, representative test coverage, and test execution synchronization. It also enhances the fine control capability of single-phase meter calibration testing under varying load conditions, meeting the consistency and stability requirements for power metering device error calibration under various operating conditions. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the main steps of the present invention;

[0036] Figure 2 This is a flowchart illustrating the process of obtaining the stable current output section identifier of the present invention.

[0037] Figure 3 This is a flowchart of the process for obtaining the error response sensitive segment sequence of the present invention;

[0038] Figure 4 This is a flowchart illustrating the process of obtaining the compressed test point list according to the present invention.

[0039] Figure 5 This is a flowchart illustrating the process of obtaining the test beat response sequence chain in this invention.

[0040] Figure 6 This is a flowchart illustrating the acquisition of the calibration test timing control instruction set of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0042] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0043] Please see Figure 1 This invention provides a technical solution, a calibration and testing method for a single-phase electricity meter, comprising the following steps:

[0044] S1: Obtain the target current value set by the signal source. During the continuous output cycle under the standard voltage maintenance state, collect multiple continuous instantaneous current output values. Based on the sequential offset trend between sampling points, identify whether the output waveform has continuous rising or falling behavior, and determine whether it is a stable output state. If there is a consistent directional fluctuation behavior, perform signal adjustment to obtain a stable current output segment identifier.

[0045] S2: Call the voltage, current and load status within the time period corresponding to the stable current output segment identifier, extract the energy pulse sequence and timestamp output by the single-phase meter, calculate the interval difference amplitude between adjacent pulses, identify the fluctuating segment and continuous segment of the energy output status, and obtain the error response sensitive segment sequence.

[0046] S3: Based on the error response sensitive section sequence, locate the upper and lower boundary intervals of the voltage and current combination under the operating conditions, analyze whether there is a continuous and consistent trend in the change of the error boundary. If there is no change between the error intervals in multiple combination points, it is determined to be an error stable area. Select the center position of the error fluctuation as the representative test point to obtain the compressed test point list.

[0047] S4: Call the compressed test point list, extract the pulse response start time, voltage signal trigger time and current stable trigger start time of the test point, and use the pulse response time as the reference time point. Compare the voltage signal trigger time and current stable trigger start time with the pulse response time. If the pulse response time is earlier than the remaining two time points, mark the test point as the main trigger point of the cycle, and postpone the remaining points in order to obtain the test cycle response sequence chain.

[0048] S5: Based on the triggering order and execution duration of the test points in the test beat response sequence chain, extract the beat interval segment of adjacent points, detect whether there is an overlap in the time coverage of the beat segment, and if there is an overlap, perform time shift processing on the start time of the test point beat to obtain the calibration test timing control instruction set;

[0049] The stable current output section identifier includes current change trend characteristics, fluctuation direction consistency parameters, and output waveform stability index. The error response sensitive section sequence includes the amplitude of power pulse interval variation, load fluctuation mapping relationship, and timing response sensitivity characteristics. The compressed test point list includes the error center point location, voltage and current stable combination points, and representative indicators of response behavior. The test cycle response sequence chain includes cycle trigger type marking, time sequence label, and response stage attribution information. The calibration test timing control instruction set includes cycle synchronization strategy parameters, time shift compensation value, and conflict section adjustment results.

[0050] Please see Figure 2 The specific steps for obtaining the stable current output section identifier are as follows:

[0051] S111: Obtain the target value of the current set by the signal source, and according to the continuous output cycle under the standard voltage maintenance state, sequentially collect multiple continuous instantaneous current output values, record the sequential offset trend between data points, and identify whether the current shows a continuous rising or falling behavior by monitoring the changing trend of the data points, and obtain the fluctuation trend identification result.

[0052] The preset target output current value Iref is read from the device setting interface, and it is confirmed that the voltage is stable within the current control cycle Tc, with voltage fluctuations not exceeding ±0.1V (this value is determined through long-term stable device operation data). Within each sampling cycle Ts=1ms, m sets of actual output current Iout are continuously collected by the ADC acquisition device. Each set of sampled data is acquired by a 16-bit A / D converter with a minimum unit of 0.1A, acquiring each sampled value within the sample time period. If Tc = 100ms within a complete cycle, n = 100 sample points can be obtained. The sequence arrangement of the sample points is recorded, and the difference ΔIi = Iout, iIout, i1 is calculated between every two adjacent sample points. The difference is then used to determine the directional offset. If ΔIi > 0.2A, it is judged as an upward trend; if ΔIi < 0.2A, it is judged as a downward trend; if |ΔIi| ≤ 0.2A, it is judged as a stable state. If ΔIi > 0.2A is continuously satisfied in the 10th to 20th sample points, the interval is identified as "continuously rising". This type of trend record is statistically analyzed by the sign trend of the difference within a set sliding window (window width is 10 sample points) to obtain the fluctuation trend identification result.

[0053] S112: Based on the fluctuation trend identification results, compare the instantaneous current output values ​​to determine whether a stable output state exists. If consistent fluctuation behavior is detected, adjust the output waveform signal and perform quantitative analysis on the signal fluctuation within the segment using the formula:

[0054] ;

[0055] Calculate the stability metric of the current to obtain the stable current output segment identifier;

[0056] SA represents a measure of current stability. This represents the real-time output current value at the i-th sampling point. Let i be the target current value at the i-th sampling point. The correction factor for the i-th sampling point As a stability adjustment factor, This represents the total number of sampling points;

[0057] Formula calculation logic: By comparing the actual output current at each sampling point With the target current value The difference, combined with the correction factor After performing a weighted summation, take the absolute value and then divide by the total number of samples n and the stability adjustment factor. The product is obtained by multiplying the products. In the calculation process, the execution... Obtain the deviation value and multiply it by the corresponding To reflect the impact of deviation on stability, the deviation terms are weighted and accumulated to obtain the overall weighted fluctuation value. The absolute value of this value is then taken to eliminate the interference of positive and negative differences in the judgment. This value is then normalized by dividing by... To unify the stability index under different sampling scales, the overall calculation process takes into account both the amplification effect of local deviations and the quantitative goal of overall stability trend. It is a weighted average normalized measure of current output fluctuation behavior.

[0058] The stability metric of current refers to the quantitative representation of the deviation between the actual current and the target current over a period of time. This metric reflects the fluctuation range of the current output at different sampling points through weighted difference calculation. The smaller the value, the closer the current is to the target value and the more stable the operating state is. Conversely, it indicates that there is strong fluctuation.

[0059] The current output value within each trend segment is compared with the corresponding target current value. The target current value Iref is maintained at a constant output of 5.0A. During the comparison, the time point corresponding to the sampling data is used, and the difference between xi and Y=5.0A is calculated to determine whether there is a continuous deviation. This deviation can be evaluated by the stability metric SA.

[0060] Meaning of parameters and calculation process:

[0061] The actual output current value at the i-th sampling point is obtained from the actual sampling.

[0062] For the target current value at the i-th sampling point, in the constant current setting, ;

[0063] The correction factor for each sampling point is set based on the distance between the sampling time point and the center point, using a symmetrical weighted coefficient array: In this example, the center point is set to the 50th sampling point;

[0064] This represents the total number of sampling points, which is 100 in this example.

[0065] The stability adjustment factor is set to 0.5 based on stable data.

[0066] Example data settings:

[0067] Table 1: Sampling Segment Data and Correction Factors

[0068] ;

[0069] As shown in Table 1, the sampling segment is set to 100 data points, the target current value is constant at 5.0A, and the correction factor is a symmetric weighted array.

[0070] The calculation process is as follows:

[0071] Calculate the difference for each sampling point and multiply it by the correction factor: for example, the first three terms are:

[0072] ;

[0073] ;

[0074] ; ......

[0075] Summing all 100 terms:

[0076] ;

[0077] Substitute into the formula to calculate:

[0078] ;

[0079] Criteria for dividing numerical intervals:

[0080] To determine the stability of the current output, the SA value is divided into the following intervals:

[0081] ;

[0082] The results indicate that the output current deviation is small within the current sampling segment, and the corrected cumulative fluctuation amplitude is within a stable range.

[0083] If the SA value is in the "stable output" range, the sampling segment is considered to meet the steady-state output condition. If multiple consecutive segments (with 3 consecutive windows) meet this condition, the overall stable state can be confirmed. Conversely, if the SA value of a certain segment exceeds 0.15 for a continuous period, or if the fluctuation trend shows a continuous shift in the same direction (such as 5 consecutive increases), the output signal is adjusted, the reference value is reset, or an alarm state is triggered.

[0084] Please see Figure 3 The specific steps for obtaining the error response sensitive segment sequence are as follows:

[0085] S211: Based on the voltage value, current value and load condition status within the time period corresponding to the stable current output segment identifier, call the power pulse sequence and the corresponding timestamp, compare the time difference of adjacent power pulses in turn, obtain the interval change between the time difference, determine whether the direction and magnitude of the interval change in adjacent time periods continue to maintain the same trend, and generate the time difference fluctuation trend value.

[0086] Select the corresponding monitoring sequence for voltage, current, and load status. Assign each pulse signal in the power pulse sequence to its acquisition time. Extract the time difference between two adjacent pulse signals within each stable current segment, and record them sequentially as follows: The difference between two adjacent time intervals is subtracted to calculate the change in time for each interval, thus obtaining the sequence. This sequence is used to reflect the variation in pulse density within adjacent time periods. When the continuous time intervals obtained from sampling within a certain segment are 2.00ms, 2.10ms, 2.12ms, 2.25ms, and 2.21ms, the following sequences are obtained sequentially: Extract the sign and absolute value of each difference term, and determine whether the sequence direction is continuously rising, falling, or maintaining a fluctuating state. If three or more consecutive differences are found... If the changes are in the same direction and the absolute values ​​are all above 0.05ms, it is considered a "same-direction change trend". At the same time, combined with the change rate of voltage and current, the amplitude stability of the change in pulse time interval in this trend segment is calculated, and the change direction and change amplitude are used as the criteria for trend identification to generate time difference fluctuation trend value.

[0087] S212: Based on the time difference fluctuation trend value, sort the amplitude of fluctuation trend changes within the differentiated time period, and call the pulse time difference value under the same trend in the time difference fluctuation trend value, using the formula:

[0088] ;

[0089] Calculate the response deviation value of the trend interval, and obtain the trend concentration shift based on the distribution density change of the response deviation value throughout the entire interval;

[0090] Where RF represents the response deviation value of the trend interval, This represents the pulse time difference within the a-th trend interval. This represents the rate of change in the a-th trend interval. This represents the directional change in the time difference between adjacent pulses within the a-th trend interval. represents the proportional coefficient of the a-th trend interval, and M represents the total number of trend intervals;

[0091] Formula calculation logic: Used to calculate the response deviation value RF of the trend interval. This value consists of two parts: the first part is the pulse time of each trend segment. With rate of change The summation and averaging of the products reflect the overall response strength of the trend in time and rate. The calculation logic is to sum the values ​​of each segment. After summing, divide by the total number of trend segments M. The second part is the fluctuation correction term, which first calculates the change in time difference for each segment. The sum of squares, minus the proportionality constant. The mean of the two values ​​is taken, and the square root of the difference is taken to obtain the degree of deviation of the trend segment in terms of fluctuation intensity. The sum of these two values ​​is the RF value, which comprehensively reflects the contribution of both time and amplitude factors to the trend response and is the quantitative basis for subsequent trend concentration judgment.

[0092] The response deviation value of the trend interval represents the average response level of each trend segment in terms of pulse time and rate of change, reflecting the degree of coupling influence of trend fluctuations on current changes in different segments. The larger the value, the stronger the deviation of the trend segment from the overall fluctuation trend.

[0093] The pulse time differences and directions of change within the trend segments are categorized and sorted. A group of segments with the same direction of change is selected as the reference interval. The rate of change, interval time, and amplitude deviation of each pulse within this group are calculated separately. The pulse time length in the a-th trend segment is then calculated. With corresponding rate of change Perform product calculations and summation, then divide by the total number of trend segments M to obtain the trend mean contribution item;

[0094] Parameter explanation and calculation process:

[0095] : The pulse duration of the a-th trend segment, in milliseconds, is directly sampled from the difference in timestamps between adjacent pulses;

[0096] The slope of the voltage and current sampling point sequence changes in the a-th trend segment, calculated as the change in A value per unit ms;

[0097] The change in time difference between adjacent pulses within the trend segment;

[0098] : The proportion coefficient of the a-th trend segment, which quantifies the influence weight of the segment in the overall trend;

[0099] M: The total number of trend segments, which is set to 5 in this embodiment;

[0100] Table 2: Trend Segment Parameter Table

[0101] ;

[0102] As shown in Table 2, the parameters for the five trend segments are set, and the calculations are performed using the formula as follows:

[0103] Part One Calculation:

[0104] ;

[0105] Part Two Calculations:

[0106] ;

[0107] ;

[0108] ;

[0109] An unreasonable correction value indicates a unit deviation in the original settings or Normalization is required; the settings will be adjusted accordingly. After being converted to standardized values ​​and recalculated, the result is:

[0110] ;

[0111] Substitute into the formula to calculate:

[0112] ;

[0113] The result indicates that the response deviation of the current trend segment is 0.24946. Combined with the judgment threshold standard of the actual trend segment (the preset stability judgment threshold is set to 0.25), it shows that the trend segment is near the stability boundary value, slightly lower than the upper limit. This means that the pulse change in this segment is within an acceptable range, but it is close to the fluctuation warning line. If the RF value continues to exceed this value in subsequent segments, or if the RF exceeds 0.25 in multiple consecutive segments, it is necessary to identify whether it is a fluctuation concentration area, or to proceed to offset analysis and sensitive area judgment.

[0114] S213: Call the trend concentration offset, filter the stable time period before and after the trend concentration offset change point based on the distribution difference of the trend concentration offset in the fluctuating and continuous areas, and merge the intervals according to the consistency of the trend direction and the fluctuation of the offset to generate an error response sensitive segment sequence.

[0115] Extract the RF value sequence {0.25, 0.21, 0.30, 0.24, 0.20} from the trend segment, calculate the mean and standard deviation, and determine the distribution difference between the fluctuating and stable regions. If the RF value of a certain segment continuously exceeds the sequence mean of 0.24 and the standard deviation is twice 0.03 (i.e., exceeding 0.30), then the segment is determined to be an abnormal offset point. Determine the location of the trend concentration offset abrupt change point, and divide the corresponding pre-stabilization time period and post-abrupt change time period. If the trend direction before and after the abrupt change point is consistent (i.e., the pulse interval increases or decreases in the same direction), and the offset exceeds 0.28, then the segment is classified as an abnormal sensitive response segment and a corresponding segment number is generated, and it is recorded into the error response sensitive segment sequence.

[0116] Please see Figure 4 The specific steps for obtaining the compressed test point list are as follows:

[0117] S311: Based on the voltage and current combination operating point located by the error response sensitive section sequence, call the error upper and lower boundary interval data corresponding to the combination operating point, process the error upper and lower boundary values ​​of the point, and generate the error boundary interval width sequence.

[0118] The actual measured voltage and current values ​​at the combined operating conditions are extracted and compared with the preset reference values ​​under standard operating conditions. The upper and lower boundaries of the error for each combined point in the difference sequence are truncated, with the upper boundary representing the maximum offset and the lower boundary representing the minimum offset. The range between these two boundaries forms the error bandwidth. A sliding extraction operation is performed on the error bandwidth of adjacent combined points. Taking a window width of 5 groups of combined points as an example, the differences between their upper and lower error boundaries are sequentially extracted and grouped into one group, denoted as . Given a set of combined operating conditions where the maximum voltage deviation is 1.5V and the minimum is -0.8V, the error width for this set is: The same processing is performed on the upper and lower boundary error values ​​of the points to generate a sequence of error boundary interval widths.

[0119] S312: Call the error boundary interval width sequence, compare the difference between the widths of adjacent error boundary intervals in the combined points according to the changes in the width of the boundary intervals of adjacent combined working conditions, determine whether there are segments where the changes in the width of the continuous error boundary intervals are lower than the error change threshold, and count the number of consecutive points in the segments and the corresponding interval range to obtain the error stable interval identification result.

[0120] We compare the absolute differences in error widths between adjacent combination points, and let the error widths of the i-th and i+1-th combination points be respectively... and Calculate the difference And set the stability change judgment threshold as If a range of consecutive differences exceeding the threshold occurs more than 3 times, it is considered an unstable error region. If consecutive differences are less than 0.3V and the direction of change is consistent, and the number of consecutive occurrences exceeds 5, it is considered a stable error region. The following sequence is set:

[0121] The adjacent differences are {0.3, 0.2, 0.1, 0.05, 0.03, 0.01}, all less than 0.3, and the direction is decreasing-increasing-increasing-decreasing. This is identified as a stable segment. The combination of points that meet the stable change range and the number of consecutive points is counted as the error stable interval. The starting and ending position indices are recorded to form the recognition result, and the error stable interval recognition result is obtained.

[0122] S313: Based on the error stability interval identification results, and according to the upper and lower limit values ​​of the error boundary in the stability interval, the following formula is used:

[0123] ;

[0124] Calculate the error fluctuation metric value in the error stability section, and select the corresponding voltage and current combination operating condition points as representative test points based on the trough value of the error fluctuation metric value within the stability section, thus obtaining a compressed list of representative test points.

[0125] Wherein, MR represents the error fluctuation measure within the stable region. This represents the difference between the upper and lower limits of the error boundary for the o-th combined point. This represents the voltage value at the o-th combination point. This represents the average voltage value in the stable region r. Q is a constant, and Q represents the number of combination points within the stable section;

[0126] Formula calculation logic: Calculate the relationship between the difference between the upper and lower boundaries of the voltage error at each combination point in the stable error range and the deviation of the voltage value at that point relative to the average voltage. This ratio is calculated for each combination point. Divide by The denominator represents the degree of deviation between the voltage at that point and the average voltage, plus a constant. To avoid the risk of division by zero, the absolute values ​​of the ratios of the combination points are summed and then divided by the number of combination points. The normalization process is achieved by linking the error magnitude with the degree of voltage deviation in the background. If the voltage at a certain point is close to the average value, the denominator becomes smaller, resulting in a greater contribution of that point to the MR value. Conversely, if the voltage deviation is large, the contribution to the overall fluctuation is small. Therefore, this formula can capture the point of severe fluctuation within the same stable range and quantify its weight. The average value MR represents the comprehensive intensity of the error fluctuation in the entire range.

[0127] The error fluctuation metric represents the normalized intensity of the error boundary values ​​at each point within the stable section under the background of local voltage deviation. It reflects the degree of concentration and amplitude of the error under the background of relative voltage difference. The larger the value, the stronger the fluctuation. This value can be used to determine whether the section is representative or abnormal, in order to assist in the subsequent extraction of test points.

[0128] The maximum difference between the upper and lower boundaries of the error within each stable segment is set to be [value]. Combined with the corresponding combination point voltage value Average voltage value in the stable section Substitute it into the formula;

[0129] Meaning of parameters and calculation process:

[0130] : The difference between the upper and lower limits of the error boundary at the 0th combination point;

[0131] Voltage value at the combination point;

[0132] Average voltage in the stable section;

[0133] : Constant perturbation term, with a value of 0.01V, to avoid the denominator approaching 0;

[0134] Number of stable segment combination points;

[0135] Table 3: Electrical Parameters of Combination Points in Stable Sections

[0136] ;

[0137] As shown in Table 3, the error fluctuation metric is calculated using five combined points within the stable region. The calculation process is as follows:

[0138] Calculate each combination point item:

[0139] Item 1: ;

[0140] Item 2: ;

[0141] Item 3: ;

[0142] Item 4: ;

[0143] Item 5: ;

[0144] Calculate the sum:

[0145] ;

[0146] Substitute into the formula to calculate:

[0147] ;

[0148] The results show that the error fluctuation metric is 4.4752, indicating that there is a large error fluctuation intensity in the combination points within the current stable segment. The error fluctuation metric is much higher than the set reference interval [0, 2.0], indicating that the fluctuation amplitude of this segment is significant and it is suitable as a representative point extraction object.

[0149] Please see Figure 5 The specific steps for obtaining the test beat response sequence chain are as follows:

[0150] S411: Call the compressed list of representative test points, extract the pulse response start time, voltage signal trigger time and current stability trigger start time recorded in the test points, establish a timing arrangement index for each test point based on the extracted three timing data, filter the time position of the pulse response start time as the reference time point corresponding to the test point, and generate the pulse start reference time sequence.

[0151] The recorded data of each test point in the test point list needs to be read one by one. For each test point, three values, namely the pulse response start time, the voltage signal trigger time, and the current stable trigger start time, are extracted from the record items. These three time parameters respectively correspond to the start instantaneous points of different physical processes and are represented in the form of time stamps, with the unit of ms or μs. These three time data are recorded under the corresponding test points to form a basic timing data set. The three data of test point TP_01 are the pulse response start time of 0.35 ms, the voltage signal trigger time of 0.42 ms, and the current stable trigger start time of 0.45 ms. Each test point is processed one by one to construct a complete test point timing data dictionary. On this basis, arrangement index processing is performed according to the three time parameter pairs of each test point, that is, three time fields are respectively established as the primary key sorting indexes. During the sorting process, the pulse response start time is used as the main reference dimension, and the arrangement method is set to be from small to large, and the sorting position of this time among all time values of each test point is calculated. If the pulse response start time of 0.35 ms is ranked 3rd among a total of 20 test points, the timing arrangement index of this test point is recorded as 3. After processing in sequence, the time sequence index where the pulse response start time is located is marked for each test point, that is, the pulse start reference time sequence.

[0152] S412: According to the reference time points of the test points in the pulse start reference time sequence, the corresponding voltage signal trigger time and the current stable trigger start time are compared in sequence to judge whether the pulse response start time is earlier than the voltage trigger time and the current trigger start time. If the judgment results are both yes, the test point is marked as the beat main trigger point to generate a beat main trigger point marking sequence;

[0153] The three timing values of the pulse response start time, the voltage signal trigger time, and the current stable trigger start time of each test point are read in sequence, and the sequence relationship among the three is compared and judged. If the pulse response start time is earlier than the other two time values, this test point will be identified as the beat main trigger point. If the three times of TP-04 are 0.28 ms, 0.31 ms, and 0.34 ms in sequence, the judgment condition is met; the judgment process uses a Boolean logic judgment method: set the judgment expression T1 < T2 and T1 < T3, where T1 is the pulse response start time, T2 is the voltage signal trigger time, and T3 is the current stable trigger start time. If the expression is true, the test point is marked as the main trigger point, which is represented by the flag bit "1" in the program, otherwise it is marked as "0". In the above judgment logic, it is necessary to pay attention to the unity of the time value unit, otherwise the judgment will fail. To avoid abnormal situations, a time normalization step can be introduced to unify it into ms-level values. After the judgment logic is executed, the test points marked as the main trigger point are extracted to obtain the beat main trigger point marking sequence.

[0154] S413: Call the main trigger point marking sequence of the clock cycle, sort the corresponding main trigger points according to the time index in the pulse start reference time sequence, and postpone the remaining points marked by the voltage signal trigger time and current stable trigger start time of the corresponding test points respectively, identify the complete test clock cycle sequence relationship, and obtain the test clock cycle response sequence chain;

[0155] Based on the test point index value marked as the main trigger point, the test points are sorted. The sorting standard is still based on the ascending order of the time index value in the pulse start reference time sequence to ensure that the sorting of the main trigger points in the overall cycle is consistent with the physical start order. The sorted test points are extracted, and the corresponding voltage signal trigger time and current stabilization trigger start time are repositioned. The remaining two timing points that originally belonged to the test point but were not used as the main trigger point are sequentially delayed. The delay amount can be set as a fixed time difference of Δt=0.05ms, or calculated based on the execution duration of the test point. If the execution time of TP-07 is 0.12ms, then the voltage signal trigger time and current stabilization trigger start time of its subsequent test points need to be increased by 0.12ms before the trigger logic is executed. The delay operation is achieved by directly modifying the timestamp and simultaneously updating the relative time offset value of the subsequent points. After completing the timing adjustment of the main trigger point and the auxiliary test points, a test cycle response sequence chain is generated.

[0156] Please see Figure 6 The specific steps for obtaining the calibration test timing control instruction set are as follows:

[0157] S511: Based on the test point triggering order and corresponding execution duration in the test beat response sequence chain, extract the pulse start time of two adjacent test points and the sum of the start time and duration of the test points, calculate the time difference between the two, and determine whether there is a segment overlap based on the difference, and generate a beat time cross-identification segment.

[0158] Extract the pulse start time and duration of the test points in the sequence, and analyze the relationship between them group by group according to the order of the test points in the sequence. For each pair of adjacent test points, the pulse start time and corresponding duration of the previous test point need to be obtained, and then the pulse start time of the next test point needs to be obtained. In actual operation, the traversal process can be set as follows: read the i-th and i+1-th test points, and process them in turn. The pulse start time and duration of the previous test point are accumulated to obtain its end time node. Then compare the pulse start time of the next test point. If the latter is earlier than the end time of the former, it means that there is a time intersection of the two beat segments. In a detection process, if there are multiple test points in the sequence that meet the intersection condition, the relative position and the index of the intersection segment need to be recorded for each point. At the same time, the start and end time periods of the intersection should be marked, and the intersection points should be managed by segment numbering. All detected segments with time coverage or overlap are collected and organized to generate beat time intersection identification segments.

[0159] S512: Call the test point data in the clock time cross-identification segment where there is cross behavior. For test points whose start time is earlier than the point but whose duration covers the period before the start, perform equal time interval time shift processing on the pulse start time respectively to obtain the calibration test timing control instruction set.

[0160] The data of test points marked as having time overlap are read one by one, with a focus on the test point that is the source of the overlap, i.e., the starting point of the overlap phenomenon where the pulse start time is earlier than the subsequent test points but the duration is longer. During the processing, the pulse start time of each overlapping test point needs to be adjusted by time shifting. To avoid excessive shifting and disruption of the overall test rhythm, a fixed step size of 0.1 milliseconds is used for the shift time. Each processing only adds the shift time to the original time and checks again whether there is still an overlap with the subsequent points. If the overlap still exists, the time shifting continues until the overlap is eliminated or the maximum number of iterations is reached. During the shifting process, the pulse start time after the shift needs to be re-recorded and replace the original start time data. The test point information after the time shift adjustment is organized into control parameter configuration entries, which include the test point number, the pulse start time after the shift, the number of shifts, etc., which is the calibration test timing control instruction set.

[0161] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A calibration and testing method for a single-phase electricity meter, characterized in that, Includes the following steps: S1: Obtain the target value of the current set by the signal source. During the continuous output cycle under the standard voltage maintenance state, collect multiple continuous instantaneous current output values. Based on the sequential offset trend between sampling points, identify whether the output waveform has continuous rising or falling behavior, and obtain the stable current output segment identifier. S2: The voltage, current, and load status within the time period corresponding to the stable current output segment identifier are retrieved. The energy pulse sequence and timestamp output by the single-phase meter are extracted, and the interval difference amplitude between adjacent pulses is calculated to obtain the error response sensitive segment sequence. The specific steps are as follows: S211: Based on the voltage value, current value and load condition status within the time period corresponding to the stable current output segment identifier, call the power pulse sequence and the corresponding timestamp, compare the time difference of adjacent power pulses in turn, obtain the interval change between the time difference, determine whether the difference direction and change amplitude of the interval change in adjacent time periods continue to maintain the same change trend, and generate a time difference fluctuation trend value. S212: Based on the time difference fluctuation trend value, sort the amplitude of fluctuation trend changes within the differentiated time period, call the pulse time difference value under the same trend in the time difference fluctuation trend value, calculate the response deviation value of the trend interval, and obtain the trend concentration offset based on the distribution density change of the response deviation value in the whole interval. S213: Call the trend concentration offset, and based on the distribution difference of the trend concentration offset in the fluctuating and continuous regions, filter the stable time period before and after the trend concentration offset mutation point, and merge the intervals according to the consistency of the trend direction and the fluctuation of the offset to generate an error response sensitive segment sequence. S3: Based on the upper and lower boundary intervals of the error under the voltage and current combination conditions located by the error response sensitive segment sequence, select the error fluctuation center location as the representative test point to obtain the compressed test point list. S4: Call the compressed test point list, extract the pulse response start time, voltage signal trigger time and current stable trigger start time of the test point, compare the voltage signal trigger time and current stable trigger start time with the pulse response start time to obtain the test beat response sequence chain.

2. The calibration and testing method for a single-phase meter according to claim 1, characterized in that, The stable current output section identifier includes current change trend characteristics, fluctuation direction consistency parameters, and output waveform stability index. The error response sensitive section sequence includes the amplitude of power pulse interval variation, load fluctuation mapping relationship, and timing response sensitivity characteristics. The compressed test point list includes the error center point location, voltage and current stable combination points, and representative indicators of response behavior. The test beat response sequence chain includes beat trigger type markers, time sequence labels, and response stage attribution information.

3. The calibration and testing method for a single-phase meter according to claim 1, characterized in that, The specific steps for obtaining the stable current output section identifier are as follows: S111: Obtain the target value of the current set by the signal source, and according to the continuous output cycle under the standard voltage maintenance state, sequentially collect multiple continuous instantaneous current output values, record the sequential offset trend between data points, and identify whether the current shows a continuous rising or falling behavior by monitoring the changing trend of the data points, and obtain the fluctuation trend identification result. S112: Based on the fluctuation trend identification result, compare the instantaneous current output value to determine whether there is a stable output state. If a consistent fluctuation behavior is detected, adjust the output waveform, perform quantitative analysis on the signal fluctuation within the segment, calculate the current stability metric value, and obtain the stable current output segment identifier.

4. The calibration and testing method for a single-phase meter according to claim 1, characterized in that, The specific steps for obtaining the compressed test point list are as follows: S311: Based on the voltage and current combination operating point located by the error response sensitive section sequence, call the error upper and lower boundary interval data corresponding to the combination operating point, process the error upper and lower boundary values ​​of the point, and generate an error boundary interval width sequence. S312: Call the error boundary interval width sequence, compare the difference between the widths of adjacent error boundary intervals in the combined points according to the changes in the width of the boundary intervals of adjacent combined working point points, determine whether there are segments where the changes in the width of the continuous error boundary intervals are lower than the error change threshold, and count the number of consecutive points in the segments and the corresponding interval range to obtain the error stable interval identification result. S313: Based on the error stability interval identification result, calculate the error fluctuation measurement value in the error stability interval according to the upper and lower limit values ​​of the error boundary in the stability interval, select the corresponding voltage and current combination working condition points as representative test points according to the low value points of the error fluctuation measurement value inside the stability interval, and obtain the compressed representative test point list.

5. The calibration and testing method for a single-phase meter according to claim 4, characterized in that, The specific steps for obtaining the test beat response sequence chain are as follows: S411: Call the compressed list of representative test points, extract the pulse response start time, voltage signal trigger time and current stable trigger start time recorded in the test points, establish a time sequence arrangement index for each test point based on the extracted three time sequence data, filter the time position of the pulse response start time as the reference time point corresponding to the test point, and generate a pulse start reference time sequence. S412: Based on the reference time point of the test point in the pulse start reference time sequence, compare the corresponding voltage signal trigger time and current stable trigger start time in turn to determine whether the pulse response start time is earlier than the voltage trigger time and the current trigger start time. If the determination result is yes, mark the test point as the main trigger point of the beat and generate the main trigger point marking sequence. S413: Call the main trigger point marking sequence of the cycle, sort the corresponding main trigger points according to the time index in the pulse start reference time sequence, and postpone the remaining points marked by the voltage signal trigger time and the current stable trigger start time of the corresponding test point, identify the complete test cycle sequence relationship, and obtain the test cycle response sequence chain.

6. The calibration and testing method for a single-phase meter according to claim 1, characterized in that, The method further includes step S5: S5: Based on the triggering order and execution duration of the test points in the test beat response sequence chain, extract the beat interval segment of adjacent points, detect whether there is an overlap in the time coverage of the beat segment, and if there is an overlap, perform time shift processing on the start time of the test point beat to obtain the calibration test timing control instruction set; The calibration test timing control instruction set includes clock synchronization strategy parameters, time shift compensation values, and conflict section adjustment results.

7. The calibration and testing method for a single-phase meter according to claim 6, characterized in that, The specific steps for obtaining the calibration test timing control instruction set are as follows: S511: Based on the test point triggering order and corresponding execution duration in the test beat response sequence chain, extract the pulse start time of two adjacent test points and the sum of the start time and duration of the test points, calculate the time difference between the two, and determine whether there is a segment overlap based on the difference, and generate a beat time cross-identification segment. S512: Call the test point data with crossover behavior in the beat time crossover identification segment, and perform equal time interval time shift processing on the pulse start time of the test points whose start time is earlier than the point but whose duration covers the period before the start, to obtain the calibration test timing control instruction set.

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