Method for measuring phase angles of voltage, current and phase angles of sectional intelligent electric energy meter

Abstract

The invention discloses a method for measuring voltage, current and phase angles of a sectional intelligent electric energy meter, and relates to the technical field of electric energy meter measurement. The sectional type intelligent electric energy meter voltage and current phase angle measurement method comprises the following steps: obtaining a sectional signal; obtaining a segmented waveform; obtaining a phase difference evaluation score; and judging the phase angle. The sampling data of the to-be-tested electric energy meter in the preset sampling point is obtained and segmented to obtain the segmented signal, and the segmented signal in the preset sampling point is input into the oscilloscope to obtain the segmented waveform and filter the waveform to obtain the instantaneous voltage value and the instantaneous current value. And then the zero crossing point time of the segmented waveform is combined to obtain a phase difference evaluation score and convert the phase difference evaluation score into a phase angle, and whether the phase angle is within a preset phase angle threshold range is judged at the same time, so that the effect of improving the phase angle measurement accuracy of the segmented intelligent electric energy meter is achieved. The problem of low phase angle measurement accuracy of a sectional type intelligent electric energy meter in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric energy meter measurement, and in particular to a voltage and current phase angle measurement method of a segmented intelligent electric energy meter. Background Art

[0002] With the accelerated advancement of smart grid construction, more stringent requirements are placed on the functions and performance of electricity meters, especially in terms of data accuracy and stability. As an important part of the smart grid, the functions that smart electricity meters need to achieve are becoming increasingly complex and diverse. However, in terms of the measurement of voltage and current phase angles, traditional methods often have problems such as poor data stability and insufficient accuracy. This is mainly due to the fluctuation of the voltage and current phase angle data output by the metering chip, as well as the jump phenomenon near a specific angle value, which increases the error of the measurement result. Therefore, in order to meet these challenges and improve the stability and accuracy of the voltage and current phase angle measurement data, researchers proposed a segmented smart electricity meter voltage and current phase angle measurement method.

[0003] The existing method for measuring the voltage and current phase angle of a smart electric energy meter divides the circuit under test into independent sections and marks them according to the structure of the circuit under test, measures the voltage and current of the electric energy meter in a predetermined segmentation order, and then analyzes the phase relationship between the voltage and current of the circuit under test after segmentation to obtain phase angle data and locate the fault point, thereby achieving accuracy and reliability of the measurement data.

[0004] For example, the invention patent with announcement number: CN107817396B discloses a method for judging line loss abnormality based on phase angle error of an electric energy meter, including: collecting and analyzing data from three-phase three-wire electric energy meters and three-phase four-wire electric energy meters; filtering out phase angle errors corresponding to electric energy meter failures by limiting phase angle data and the number of abnormal occurrences; and judging whether the line loss abnormality is caused by the phase angle error of the electric energy meter based on the results of the collected data analysis.

[0005] For example, the patent application with publication number: CN116908773A discloses a method, device and related equipment for measuring the voltage and current phase angle of an intelligent electric energy meter, including: obtaining the original value of the voltage and current phase angle through a preset data acquisition task, and converting the original value of the voltage and current phase angle into a new value of the angle to be calculated; setting the new value of the angle to be calculated as the angle value to be calculated, and sending the angle value to be calculated to a preset annular data cache space; calculating the annular data mean of the angle value to be calculated in the annular data cache space through a preset data calculation task; and outputting the annular data mean as the measurement value of the voltage and current phase angle.

[0006] However, in the process of implementing the technical solution of the invention in the embodiments of the present application, the present application found that the above technology has at least the following technical problems:

[0007] In the prior art, load changes in the circuit of the measured electric energy meter usually affect the measurement structure of the phase angle, causing changes in the waveforms of the voltage and current. Secondly, in the segmented measurement, if there are too many segments, it may increase the difficulty of phase angle measurement, while if there are too few segments, it may not accurately reflect the actual situation of the waveform in the circuit, resulting in the problem of low phase angle measurement accuracy of the segmented smart electric energy meter. Summary of the invention

[0008] The embodiment of the present application solves the problem of low phase angle measurement accuracy of segmented smart power meters in the prior art by providing a method for measuring the voltage and current phase angle of a segmented smart power meter, thereby improving the phase angle measurement accuracy of the segmented smart power meter.

[0009] The embodiment of the present application provides a segmented smart energy meter voltage and current phase angle measurement method, comprising the following steps: S1, obtaining sampling data of the energy meter to be tested within a preset sampling point and performing segmented processing to obtain a segmented signal, wherein the sampling data includes voltage data and current data, the segmented processing includes a first segmented processing and a second segmented processing, and the segmented signal includes a first segmented signal and a second segmented signal, wherein the first segmented signal is a voltage value after the voltage is marked within the segmented sampling point, and the second segmented signal is a current value after the current is marked within the segmented sampling point; S2, inputting the segmented signal within the preset sampling point into an oscilloscope to obtain a segmented waveform, and filtering the obtained segmented waveform at the same time Processing to obtain instantaneous voltage value and instantaneous current value, the segmented waveform includes a voltage waveform and a current waveform, the instantaneous voltage value is the voltage peak value of the voltage waveform within a preset sampling period, and the instantaneous current value is the current peak value of the current waveform within a preset sampling period; S3, real-time recording of the zero-crossing time of the segmented waveform to obtain a phase difference evaluation score, the zero-crossing time includes the voltage zero-crossing time and the current zero-crossing time; S4, converting the phase difference evaluation score into a phase angle and determining whether the phase angle is within a preset phase angle threshold range. If so, it indicates that the electric energy meter to be tested is in a phase balance state within the preset sampling period, otherwise returns to S1 until the converted phase angle is within the preset phase angle threshold range.

[0010] Furthermore, the specific steps of obtaining the sampling data of the electric energy meter to be tested within the preset sampling points and performing segmented processing are: converting the voltage data into a voltage signal and recording the voltage amplitude information of the voltage signal at the segmented sampling points in real time, and the voltage amplitude information is used to reflect the peak value and valley value of the voltage signal within the preset sampling period at the segmented sampling points; converting the current data into a current signal and recording the current amplitude information of the current signal at the segmented sampling points in real time, and the current amplitude information is used to reflect the peak value and valley value of the current signal within the preset sampling period at the segmented sampling points.

[0011] Furthermore, the acquisition of the segmented signal also includes acquiring a phase shift evaluation score based on the acquired voltage amplitude information and current amplitude information, and the phase shift evaluation score is used to measure the degree of phase deviation between the current signal and the voltage signal in the segmented sampling point within the same timestamp. The specific method is as follows: real-time recording of the number of peak values ​​and the number of valley values ​​of the current signal and the voltage signal within the same timestamp within a preset sampling period, and combining the voltage timestamp and the current timestamp to obtain the phase shift evaluation score, the voltage timestamp indicating the time period within the preset sampling period for the voltage signal to reach the peak value from the valley value, and the current timestamp indicating the time period within the preset sampling period for the current signal to reach the peak value from the valley value.

[0012] Furthermore, the phase shift evaluation score is calculated by the following formula:

[0013]

[0014] Where q is the number of the segmented sampling point, q = 1, 2, ..., Q, Q is the total number of segmented sampling points, n is the number of the preset sampling period, n = 1, 2, ..., N, N is the total number of preset sampling periods, e is a natural constant, WEI q.n A1 represents the phase offset evaluation score of the segmented signal in the nth preset sampling period at the qth segmented sampling point. q.n Indicates the number of peak values ​​of the voltage signal in the nth preset sampling period at the qth segment sampling point, B1 q.n A2 represents the number of peak values ​​of the current signal in the nth preset sampling period at the qth segment sampling point. q.n Indicates the number of valley values ​​of the voltage signal in the nth preset sampling period at the qth segment sampling point, B2 q.n Indicates the number of valley values ​​of the current signal in the nth preset sampling period at the qth segment sampling point, A3 q.n Indicates the voltage timestamp of the voltage signal in the nth preset sampling period at the qth segment sampling point, B3 q.n Indicates the current timestamp of the current signal in the nth preset sampling period at the qth segment sampling point.

[0015] Furthermore, the filtering process of the acquired segmented waveform also includes real-time monitoring of the harmonics in the segmented waveform to obtain a harmonic distortion evaluation score, the harmonic distortion evaluation score is used to measure the influence of the harmonic components on the segmented waveform, and the specific steps of obtaining the harmonic distortion evaluation score are: converting the time domain signal in the segmented waveform into a frequency domain signal through Fourier transform to obtain the fundamental signal amplitude and the harmonic signal amplitude, the frequency domain signal is used to reflect the frequency distribution of the fundamental signal and the harmonic signal in the segmented waveform, the fundamental signal amplitude includes the voltage fundamental signal amplitude and the current fundamental signal amplitude, the harmonic signal amplitude includes the voltage harmonic signal amplitude and the current harmonic signal amplitude; real-time recording of the duration of the voltage harmonic signal amplitude and the current harmonic signal amplitude within a preset sampling period, and combining the acquired phase offset evaluation score, fundamental signal amplitude and harmonic signal amplitude to obtain the harmonic distortion evaluation score.

[0016] Furthermore, the harmonic distortion evaluation score is calculated by the following formula:

[0017]

[0018] In the formula, XIE q.n Indicates the harmonic distortion evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, C1 q.n Indicates the voltage harmonic signal amplitude of the voltage waveform in the nth preset sampling period at the qth segment sampling point, D1 q.n Indicates the voltage fundamental signal amplitude of the voltage waveform in the nth preset sampling period at the qth segment sampling point, C2 q.n Indicates the duration of the voltage harmonic signal amplitude at the qth segment sampling point of the voltage waveform within the nth preset sampling period, C3 q.n Indicates the duration of the current harmonic signal amplitude in the nth preset sampling period at the qth segment sampling point of the current waveform, D2 q.n Indicates the duration of the fundamental signal amplitude in the nth preset sampling period at the qth segment sampling point, C4 q.n Indicates the current harmonic signal amplitude of the current waveform in the nth preset sampling period at the qth segment sampling point, D3 q.n It represents the amplitude of the current fundamental wave signal of the current waveform in the nth preset sampling period at the qth segment sampling point.

[0019] Furthermore, the real-time recording of the zero-crossing time of the segmented waveform also includes obtaining a relative delay evaluation score based on the obtained instantaneous voltage value and instantaneous current value, and the relative delay evaluation score is used to reflect the deviation between the voltage waveform and the current waveform. The relative delay evaluation score is calculated by the following formula:

[0020]

[0021] In the formula, YAN q.n Represents the relative delay evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, P1 q.n It represents the instantaneous voltage value of the voltage waveform in the nth preset sampling period at the qth segment sampling point, P20 represents the reference instantaneous voltage value, ΔP represents the instantaneous voltage value reference deviation, Q1 q.n represents the instantaneous current value of the current waveform in the nth preset sampling period at the qth segment sampling point, Q20 represents the reference instantaneous current value, ΔQ represents the instantaneous current value reference deviation, XIE0 represents the reference harmonic distortion evaluation score, and ΔXIE represents the harmonic distortion evaluation score reference deviation.

[0022] Furthermore, the voltage zero-crossing time includes a negative voltage zero-crossing time and a positive voltage zero-crossing time, and the current zero-crossing time includes a negative current zero-crossing time and a positive current zero-crossing time.

[0023] Furthermore, the calculation expression of the phase difference evaluation score is:

[0024] CHA q.n =δ*YAN q.n +γ*WEI q.n +|F1 q.n -F2 q.n |+|Z1 q.n -Z2 q.n |;

[0025] Where q is the number of the segmented sampling point, q = 1, 2, ..., Q, Q is the total number of segmented sampling points, n is the number of the preset sampling period, n = 1, 2, ..., N, N is the total number of preset sampling periods, CHA q.n represents the phase difference evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, δ represents the relative delay evaluation score correction factor, YAN q.n represents the relative delay evaluation score of the segmented waveform in the qth segment sampling point within the nth preset sampling period, γ represents the phase offset evaluation score correction factor, WEI q.n Indicates the phase offset evaluation score of the segmented signal in the nth preset sampling period at the qth segmented sampling point, F1 q.n Indicates the negative voltage zero crossing time of the voltage waveform in the nth preset sampling cycle at the qth segment sampling point, F2 q.n Indicates the negative current zero-crossing time of the current waveform in the nth preset sampling cycle at the qth segment sampling point, Z1 q.nIndicates the positive voltage zero crossing time of the voltage waveform in the nth preset sampling cycle at the qth segment sampling point, Z2 q.n It indicates the positive current zero-crossing time of the current waveform in the nth preset sampling period at the qth segment sampling point.

[0026] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0027] 1. The sampling data of the electric energy meter to be tested within the preset sampling points is obtained and segmented processing is performed to obtain the segmented signal. At the same time, the segmented signal within the preset sampling points is input into the oscilloscope to obtain the segmented waveform and filter processing is performed to obtain the instantaneous voltage value and the instantaneous current value. Then, the zero-crossing time of the segmented waveform is combined to obtain the phase difference evaluation score and convert it into a phase angle. At the same time, it is judged whether the phase angle is within the preset phase angle threshold range, thereby achieving the improvement of the accuracy and reliability of the phase difference evaluation score acquisition, and then achieving the improvement of the phase angle measurement accuracy of the segmented intelligent electric energy meter, which effectively solves the problem of low phase angle measurement accuracy of the segmented intelligent electric energy meter in the prior art.

[0028] 2. By converting voltage data into voltage signals and recording the voltage amplitude information of the voltage signals at the segmented sampling points in real time, and converting current data into current signals and recording the current amplitude information of the current signals at the segmented sampling points in real time, the accuracy of obtaining voltage amplitude signals and current amplitude information is improved, thereby achieving more accurate acquisition of voltage peak value and current peak value within the preset sampling period.

[0029] 3. The time domain signal in the segmented waveform is converted into a frequency domain signal through Fourier transform to obtain the fundamental signal amplitude and the harmonic signal amplitude, and then the duration of the voltage harmonic signal amplitude and the current harmonic signal amplitude within the preset sampling period is recorded in real time. At the same time, the obtained phase shift evaluation score, fundamental signal amplitude and harmonic signal amplitude are combined to obtain the harmonic distortion evaluation score, thereby achieving more accurate acquisition of the fundamental signal amplitude and the harmonic signal amplitude, and then achieving improved accuracy and reliability in obtaining the harmonic distortion evaluation score. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A flow chart of a method for measuring voltage and current phase angles of a segmented smart energy meter provided in an embodiment of the present application;

[0031] Figure 2 A three-dimensional coordinate analysis diagram of the relative delay evaluation score provided in an embodiment of the present application;

[0032] Figure 3 A flowchart of abnormal phase angle zero-crossing detection provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] The embodiment of the present application solves the problem of low phase angle measurement accuracy of segmented smart energy meters in the prior art by providing a segmented smart energy meter voltage and current phase angle measurement method. The method obtains voltage data and current data of the energy meter to be tested within a preset sampling point and performs a first segmentation process and a second segmentation process to obtain a segmented signal. The segmented signal within the preset sampling point is input into an oscilloscope to obtain a segmented waveform. The acquired segmented waveform is filtered to obtain a voltage peak value of the voltage waveform and a current peak value of the current waveform within a preset sampling period. The voltage zero crossing time and the current zero crossing time of the segmented waveform are then recorded in real time to obtain a phase difference evaluation score. Finally, the phase difference evaluation score is converted into a phase angle and it is determined whether the phase angle is within a preset phase angle threshold range. If so, it indicates that the energy meter to be tested is in a phase balance state within the preset sampling period. Otherwise, the segmented signal is re-acquired until the converted phase angle is within the preset phase angle threshold range, thereby improving the phase angle measurement accuracy of the segmented smart energy meter.

[0034] The technical solution in the embodiment of the present application is to solve the problem of low phase angle measurement accuracy of the above-mentioned segmented smart energy meter. The overall idea is as follows:

[0035] The sampling data of the electric energy meter to be tested within the preset sampling points is obtained and segmented processing is performed to obtain segmented signals. At the same time, the segmented signals within the preset sampling points are input into the oscilloscope to obtain segmented waveforms and filtered to obtain instantaneous voltage and instantaneous current values. Then, the zero-crossing time of the segmented waveform is combined to obtain the phase difference evaluation score and convert it into a phase angle. At the same time, it is judged whether the phase angle is within the preset phase angle threshold range, thereby achieving the effect of improving the phase angle measurement accuracy of the segmented smart electric energy meter.

[0036] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0037] like Figure 1As shown, it is a flow chart of a voltage and current phase angle measurement method of a segmented smart energy meter provided by an embodiment of the present application, the method comprising the following steps: S1, obtaining sampling data of the energy meter to be measured within a preset sampling point and performing segment processing to obtain a segment signal, the preset sampling point is a segment sampling point set by a preset person according to actual measurement requirements, the sampling data includes voltage data and current data, the segment processing includes a first segment processing and a second segment processing, the first segment processing is used to distribute the voltage data to the segment sampling point and perform voltage marking, the second segment processing is used to divide the current data into Segmented sampling points are assigned and current is marked, the segmented signal includes a first segmented signal and a second segmented signal, the first segmented signal is the voltage value after the voltage mark in the segmented sampling point, and the second segmented signal is the current value after the current mark in the segmented sampling point; S2, the segmented signal in the preset sampling point is input into the oscilloscope to obtain a segmented waveform, and the obtained segmented waveform is filtered to obtain an instantaneous voltage value and an instantaneous current value, the segmented waveform includes a voltage waveform and a current waveform, the oscilloscope is connected to the electric energy meter to be tested, and the voltage waveform is used to reflect the voltage of the electric energy meter to be tested within a preset sampling period The current waveform is used to reflect the fluctuation of the current of the electric energy meter to be tested within the preset sampling period. The filtering process is used to remove the interference signal in the segmented waveform. The instantaneous voltage value is the voltage peak value of the voltage waveform within the preset sampling period, and the instantaneous current value is the current peak value of the current waveform within the preset sampling period. S3, real-time recording of the zero-crossing time of the segmented waveform to obtain the phase difference evaluation score, the zero-crossing time includes the voltage zero-crossing time and the current zero-crossing time. The voltage zero-crossing time is used to reflect the instantaneous time when the voltage peak appears in the voltage waveform within the preset sampling period, and the current zero-crossing time is used to reflect the instantaneous time when the current peak appears in the current waveform within the preset sampling period. The phase difference evaluation score is used to reflect the relative position of the segmented waveform on the same time axis in the preset sampling period; S4, converting the phase difference evaluation score into a phase angle and judging whether the phase angle is within the preset phase angle threshold range. If so, it indicates that the electric energy meter to be tested is in a phase balance state within the preset sampling period, otherwise returns to S1 until the converted phase angle is within the preset phase angle threshold range. The preset phase angle threshold is represented by the result of summing and averaging the historical phase angles in the preset database by the preset personnel.

[0038] In this embodiment, the voltage data of the electric energy meter to be tested at the preset sampling points is usually measured in real time by a voltage sensor, and the current data of the electric energy meter to be tested at the preset sampling points is usually measured in real time by a current sensor, wherein the time intervals between the preset sampling points should be kept consistent (such as one minute, ten minutes). Therefore, in the segmented measurement process, a synchronous clock is required to record in real time to ensure that the segmented sampling points are completed within the synchronization time to reduce the error of the sampling data; interference signals in the voltage signal and the current signal are usually suppressed by a bandpass filter, wherein the interference signal is usually an electromagnetic interference signal generated by electromagnetic radiation in the electric energy meter to be tested, which helps to improve the quality and stability of the voltage signal and the current signal; the instantaneous voltage value and the instantaneous current value are usually automatically determined by the peak detection function in the oscilloscope, and in practical applications, they can also be determined by The highest point of the waveform is manually measured for estimation, but there will be a certain deviation. It should be noted that when using an oscilloscope to measure instantaneous voltage and current values, multiple measurements are required to take the average value to improve the reliability of the measurement results; the voltage zero-crossing time refers to the instantaneous time when the voltage waveform crosses the zero level from positive (or negative) to negative (or positive) within the preset sampling period, which is usually used to reflect the change node of the voltage waveform within the preset sampling period; the current zero-crossing time refers to the instantaneous time when the current waveform crosses the zero level from positive (or negative) to negative (or positive) within the preset sampling period, which is usually used to reflect the change node of the current waveform within the preset sampling period; by real-time recording of the zero-crossing time of the segmented waveform and real-time monitoring of the changes of the segmented waveform within the preset sampling period, the phase angle measurement accuracy of the segmented smart electricity meter is improved.

[0039] Furthermore, the specific steps of obtaining the sampling data of the electric energy meter to be tested within the preset sampling points and performing segmented processing are: converting the voltage data into a voltage signal and recording the voltage amplitude information of the voltage signal at the segmented sampling points in real time, the voltage signal is a digital voltage signal converted by an analog-to-digital converter, and the voltage amplitude information is used to reflect the peak value and valley value of the voltage signal within the preset sampling period at the segmented sampling points; converting the current data into a current signal and recording the current amplitude information of the current signal at the segmented sampling points in real time, the current signal is a digital current signal converted by an analog-to-digital converter, and the current amplitude information is used to reflect the peak value and valley value of the current signal within the preset sampling period at the segmented sampling points.

[0040] In this embodiment, the voltage data is usually subjected to signal conditioning (such as amplification and filtering) through a voltage sensor to obtain a voltage signal, and the voltage signal is converted into a digital signal (i.e., a digital voltage signal) through an analog-to-digital converter according to a preset analog-to-digital conversion accuracy (such as 12 bits or 16 bits) and a sampling rate (such as the number of sampling points per second), and then the acquired digital voltage signal is divided into multiple time periods (i.e., segments), each segment usually contains a fixed number of sampling points, and the amplitude information of the voltage signal in each segment is recorded in real time, and the maximum and minimum values ​​of the voltage waveform within a preset sampling period, i.e., the peak and valley values ​​of the voltage signal, are observed in real time; similarly, the current data is usually subjected to signal conditioning (such as amplification and filtering) through a current sensor to obtain a current signal, and at the same time The current signal is converted into a digital signal (i.e., a digital current signal) by an analog-to-digital converter according to a preset analog-to-digital conversion accuracy (e.g., 12 bits or 16 bits) and a sampling rate (e.g., the number of sampling points per second), and then the acquired digital current signal is divided into multiple time periods (i.e., segments), each segment usually contains a fixed number of sampling points, and the amplitude information of the current signal in each segment is recorded in real time, and the maximum and minimum values ​​of the current waveform within a preset sampling period, i.e., the peak and valley values ​​of the current signal, are observed in real time; in summary, converting the voltage signal and the current signal into corresponding digital signals by an analog-to-digital converter helps to more clearly observe the peak and valley values ​​of the voltage signal and the current signal within the preset sampling period, thereby improving the accuracy and reliability of the segmented processing of the sampling data.

[0041] Furthermore, a segmented signal is obtained, and then a phase shift evaluation score is obtained based on the obtained voltage amplitude information and current amplitude information. The phase shift evaluation score is used to measure the degree of phase deviation between the current signal and the voltage signal in the segmented sampling point at the same timestamp. The specific method is as follows: real-time recording of the number of peak values ​​and valley values ​​of the current signal and the voltage signal at the same timestamp in a preset sampling period, and combining the voltage timestamp and the current timestamp to obtain the phase shift evaluation score. The voltage timestamp indicates the time period in which the voltage signal reaches the peak value from the valley value in the preset sampling period, and the current timestamp indicates the time period in which the current signal reaches the peak value from the valley value in the preset sampling period.

[0042] In this embodiment, it should be noted that, in the calculation formula of the phase offset evaluation score, when the preset sampling period only includes one voltage peak, valley and one current peak, valley, the phase offset evaluation score is not calculated; it should be understood that since the phase difference may be a positive number or a negative number, it usually depends on whether the current leads or lags behind the voltage. Therefore, in order to improve the accuracy of the phase offset evaluation score, the voltage timestamp and the current timestamp need to be considered, wherein the voltage timestamp represents the difference between the time when the voltage signal reaches the peak value and the time when it reaches the valley value within the preset sampling period, and the current timestamp represents the difference between the time when the current signal reaches the peak value and the time when it reaches the valley value within the preset sampling period, thereby achieving more accurate acquisition of the phase offset evaluation score.

[0043] Furthermore, the phase shift evaluation score is calculated by the following formula:

[0044]

[0045] Where q is the number of the segmented sampling point, q = 1, 2, ..., Q, Q is the total number of segmented sampling points, n is the number of the preset sampling period, n = 1, 2, ..., N, N is the total number of preset sampling periods, e is a natural constant, WEI q.n A1 represents the phase offset evaluation score of the segmented signal in the nth preset sampling period at the qth segmented sampling point. q.n Indicates the number of peak values ​​of the voltage signal in the nth preset sampling period at the qth segment sampling point, B1 q.n A2 represents the number of peak values ​​of the current signal in the nth preset sampling period at the qth segment sampling point. q.n Indicates the number of valley values ​​of the voltage signal in the nth preset sampling period at the qth segment sampling point, B2 q.n Indicates the number of valley values ​​of the current signal in the nth preset sampling period at the qth segment sampling point, A3 q.n Indicates the voltage timestamp of the voltage signal in the nth preset sampling period at the qth segment sampling point, B3 q.n Indicates the current timestamp of the current signal in the nth preset sampling period at the qth segment sampling point.

[0046] In this embodiment, when When A1 q.n =B1 q.n , A2 q.n =B2 q.n And A3 q.n =B3 q.n, at this time, the phase shift evaluation score takes the minimum value; it should be understood that the algorithm of this embodiment combines the peak coefficient, valley coefficient and timestamp coefficient factors, and comprehensively analyzes to obtain the phase shift evaluation score, wherein the peak coefficient is the ratio of the number of peaks of the voltage signal to the number of peaks of the current signal, the valley coefficient is the ratio of the number of valleys of the voltage signal to the number of valleys of the current signal, and the timestamp coefficient is the ratio of the voltage timestamp to the current timestamp. It should be noted that the peak coefficient, valley coefficient and timestamp coefficient in this formula not only unilaterally affect the value of the phase shift evaluation score, but the timestamp coefficient also indirectly affects the values ​​of the peak coefficient and the valley coefficient. However, the peak coefficient and the valley coefficient are usually not directly "indirectly affected" by the timestamp coefficient, but are indirectly affected by adjusting the detection process of the peak and valley values. Assuming that there is a fixed time delay (i.e., timestamp difference) between the voltage signal and the current signal, the signals can be time-aligned before detecting the peak value, which helps to more accurately calculate the number of peaks and valleys, and thus obtain more accurate peak coefficients and valley coefficients. By considering the influence of peak coefficients, valley coefficients and timestamp coefficients on the phase deviation coefficient, the accuracy and reliability of phase shift evaluation scores are improved, thereby improving the accuracy of phase angle measurement of segmented smart energy meters, effectively solving the problem of low phase angle measurement accuracy of segmented smart energy meters in the prior art.

[0047] Furthermore, the acquired segmented waveform is filtered, which also includes real-time monitoring of harmonics in the segmented waveform to obtain a harmonic distortion evaluation score. The harmonic distortion evaluation score is used to measure the degree of influence of harmonic components on the segmented waveform. The specific steps for obtaining the harmonic distortion evaluation score are: converting the time domain signal in the segmented waveform into a frequency domain signal through Fourier transform to obtain the fundamental signal amplitude and the harmonic signal amplitude. The frequency domain signal is used to reflect the frequency distribution of the fundamental signal and the harmonic signal in the segmented waveform. The fundamental signal represents the same frequency component as the power supply frequency of the electric energy meter to be tested. The fundamental signal amplitude includes the voltage fundamental signal amplitude and the current fundamental signal amplitude, and the harmonic signal amplitude includes the voltage harmonic signal amplitude and the current harmonic signal amplitude; the duration of the voltage harmonic signal amplitude and the current harmonic signal amplitude within a preset sampling period is recorded in real time, and the harmonic distortion evaluation score is obtained by combining the acquired phase offset evaluation score, the fundamental signal amplitude and the harmonic signal amplitude.

[0048] In this embodiment, in practical applications, Fourier transform is usually used to directly convert the time domain signal into a frequency domain signal. In the frequency domain, the various frequency components of the signal can be more clearly observed in combination with the voltage waveform and current waveform in the oscilloscope, and the amplitude of each frequency component (i.e., the voltage fundamental signal amplitude, the current fundamental signal amplitude, the voltage harmonic signal amplitude and the current harmonic signal amplitude) can be directly read, wherein the fundamental wave usually corresponds to the maximum amplitude point in the spectrum, and the harmonic is the frequency component at an integer multiple of the fundamental wave frequency. The voltage fundamental signal amplitude is the maximum value of the fundamental signal in the voltage signal within the preset sampling period, the current fundamental signal amplitude is the maximum value of the fundamental signal in the current signal within the preset sampling period, the voltage harmonic signal amplitude is the maximum value of the harmonic signal in the voltage signal within the preset sampling period, and the current harmonic signal amplitude is the maximum value of the harmonic signal in the current signal within the preset sampling period, thereby achieving more accurate acquisition of the harmonic distortion evaluation score.

[0049] Furthermore, the harmonic distortion evaluation score is calculated using the following formula:

[0050]

[0051] In the formula, XIE q.n Indicates the harmonic distortion evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, C1 q.n Indicates the voltage harmonic signal amplitude of the voltage waveform in the nth preset sampling period at the qth segment sampling point, D1 q.n Indicates the voltage fundamental signal amplitude of the voltage waveform in the nth preset sampling period at the qth segment sampling point, C2 q.n Indicates the duration of the voltage harmonic signal amplitude at the qth segment sampling point of the voltage waveform within the nth preset sampling period, C3 q.n Indicates the duration of the current harmonic signal amplitude in the nth preset sampling period at the qth segment sampling point of the current waveform, D2 q.n Indicates the duration of the fundamental signal amplitude in the nth preset sampling period at the qth segment sampling point, C4 q.n Indicates the current harmonic signal amplitude of the current waveform in the nth preset sampling period at the qth segment sampling point, D3 q.n It represents the amplitude of the current fundamental wave signal of the current waveform in the nth preset sampling period at the qth segment sampling point.

[0052] In this embodiment, in order to simplify the analysis, we define Where, CD1 q.n Indicates the proportion of voltage harmonic signals in the nth preset sampling period at the qth segment sampling point of the voltage waveform, CD2 q.nIndicates the proportion of the harmonic signal duration in the nth preset sampling period at the qth segment sampling point of the segmented waveform, CD3 q.n It represents the proportion of current harmonic signals in the nth preset sampling period at the qth segment sampling point of the current waveform. The simplified calculation formula for the harmonic distortion evaluation score is: XIE q.n =tanh(WEI q.n +CD1 q.n +CD2 q.n +CD3 q.n ), the statistical table of changes in harmonic distortion evaluation scores is shown in Table 1:

[0053] Table 1 Statistics of changes in harmonic distortion evaluation scores

[0054]

[0055]

[0056] It should be understood that, in the calculation formula of the present embodiment, each preset sampling period here only includes one voltage peak value, valley value and one current peak value, valley value. The fundamental signal represents the main operating frequency of the electric energy meter to be tested (usually 50HZ or 60HZ), which is usually continuous when the electric energy meter to be tested is working normally. As long as the electric energy meter to be tested generates current and voltage during operation, the amplitude of the fundamental signal will continue to exist, that is, the amplitude duration of the fundamental signal is usually the time difference between the end time and the start time of the fundamental signal in the preset sampling period; the amplitude duration of the voltage harmonic signal is usually the time difference between the end time and the start time of the harmonic signal in the voltage waveform in the preset sampling period, and the amplitude duration of the current harmonic signal is usually the time difference between the end time and the start time of the harmonic signal in the current waveform in the preset sampling period.

[0057] It should be noted that, under normal working conditions of the electric energy meter to be tested, the fundamental wave is the main component in the segmented waveform. As long as the electric energy meter to be tested starts working, the fundamental wave will be generated, while the harmonic component is generated during the working process of the electric energy meter to be tested, which is usually less than or equal to the fundamental wave component, that is, C1 q.n ≤D1 q.n , C2 q.n +C3 q.n ≤D2 q.n , C4 q.n ≤D3 q.n , when WEI q.n =1,C1 q.n =D1 q.n , C2 q.n +C3 q.n =D2 q.n And C4 q.n =D3q.n When , the corresponding harmonic distortion evaluation score takes the maximum value (i.e. tanh4=0.999); by considering the influence of the harmonic components in the segmented waveform on the fundamental components, the accuracy and reliability of obtaining the harmonic distortion evaluation score are improved, thereby achieving an improvement in the accuracy of the phase angle measurement of the segmented smart energy meter, and effectively solving the problem of low phase angle measurement accuracy of the segmented smart energy meter in the prior art.

[0058] Furthermore, the zero-crossing time of the segmented waveform is recorded in real time. Previously, the relative delay evaluation score is obtained according to the instantaneous voltage value and instantaneous current value. The relative delay evaluation score is used to reflect the instantaneous value deviation and harmonic distortion deviation between the voltage waveform and the current waveform. The relative delay evaluation score is calculated by the following formula:

[0059]

[0060] In the formula, YAN q.n Represents the relative delay evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, P1 q.n It represents the instantaneous voltage value of the voltage waveform in the nth preset sampling period at the qth segment sampling point, P20 represents the reference instantaneous voltage value, ΔP represents the instantaneous voltage value reference deviation, Q1 q.n represents the instantaneous current value of the current waveform in the nth preset sampling period at the qth segment sampling point, Q20 represents the reference instantaneous current value, ΔQ represents the instantaneous current value reference deviation, XIE0 represents the reference harmonic distortion evaluation score, and ΔXIE represents the harmonic distortion evaluation score reference deviation.

[0061] In this embodiment, it should be noted that in the calculation formula of the relative delay evaluation score, each preset sampling period here only includes one voltage peak value, valley value and one current peak value, valley value; the reference instantaneous voltage value is usually represented by the result of summing and averaging the historical instantaneous voltage values ​​in the preset database, and the instantaneous voltage value reference deviation is usually represented by the result of summing and averaging the historical instantaneous voltage deviation values ​​in the preset database, wherein the historical instantaneous voltage deviation value is usually the difference between the historical reference instantaneous voltage value and the historical instantaneous voltage value; the reference instantaneous current value is usually represented by the result of summing and averaging the historical instantaneous current values ​​in the preset database. It is shown that the instantaneous current value reference deviation is usually represented by the result of summing and averaging the historical instantaneous current deviation values ​​in the preset database, wherein the historical instantaneous current deviation value is usually the difference between the historical reference instantaneous current value and the historical instantaneous current value; the reference harmonic distortion assessment score is usually represented by the result of summing and averaging the historical harmonic distortion assessment scores in the preset database, and the harmonic distortion assessment score reference deviation is usually represented by the result of summing and averaging the historical harmonic distortion assessment score deviation values ​​in the preset database, wherein the historical harmonic distortion assessment score deviation value is usually the difference between the historical reference harmonic distortion assessment score and the historical harmonic distortion assessment score.

[0062] Specifically, to simplify the analysis, define In the formula, PQ q.n Indicates the instantaneous value deviation coefficient of the segmented waveform in the nth preset sampling period at the qth segment sampling point, X1 q.n It represents the harmonic distortion coefficient of the voltage waveform in the nth preset sampling period at the qth segment sampling point. The simplified calculation formula of the relative delay evaluation score is: like Figure 2 As shown in FIG. 1 , a three-dimensional coordinate analysis diagram of the relative delay evaluation score provided in the embodiment of the present application is shown. It can be seen from the figure that the relative delay evaluation score increases with the increase of the instantaneous value deviation coefficient and the harmonic distortion coefficient. It should be noted that when PQ q.n =0 and X1 q.n = 0, the corresponding relative offset rate is equal to 0. At this time, the instantaneous value deviation and harmonic distortion deviation between the voltage waveform and the current waveform are both 0, that is, P1 q.n =P20,Q1 q.n =Q20 and XIE q.n =XIE0, wherein the instantaneous value deviation includes the instantaneous voltage deviation and the instantaneous current deviation, the instantaneous voltage deviation represents the absolute value of the difference between the instantaneous voltage value and the reference instantaneous voltage value, the instantaneous current deviation represents the absolute value of the difference between the instantaneous current value and the reference instantaneous current value, and the harmonic distortion deviation represents the absolute value of the difference between the harmonic distortion evaluation score and the reference harmonic distortion evaluation score.

[0063] It should be understood that the algorithm of this embodiment combines the instantaneous value deviation coefficient and the harmonic distortion coefficient factors, and comprehensively analyzes to obtain the relative delay evaluation score. The instantaneous value deviation coefficient and the harmonic distortion coefficient in this formula not only unilaterally affect the value of the relative delay evaluation score, but the harmonic distortion coefficient also indirectly affects the value of the instantaneous value deviation coefficient. When there are harmonics in the voltage or current waveform, these harmonic components will be superimposed on the fundamental wave, resulting in waveform distortion. This distortion usually makes the instantaneous value measured at a specific sampling point different from the instantaneous value when there is no harmonic. If the instantaneous value is different from the instantaneous value when there is no harmonic due to harmonic distortion, the relative delay evaluation score will be obtained. If the harmonic distortion causes the measured instantaneous value to change, the instantaneous value deviation coefficient obtained will also change accordingly. In summary, since the harmonic distortion indirectly affects the value of the instantaneous value deviation coefficient, and thus indirectly affects the value of the relative delay evaluation score, it is necessary to comprehensively consider the influence of the harmonic distortion coefficient on the instantaneous value deviation coefficient, thereby achieving the improvement of the accuracy and reliability of the relative delay evaluation score acquisition, and then achieving the improvement of the phase angle measurement accuracy of the segmented smart electric energy meter, which effectively solves the problem of low phase angle measurement accuracy of the segmented smart electric energy meter in the prior art.

[0064] Furthermore, the voltage zero-crossing time includes the negative voltage zero-crossing time and the positive voltage zero-crossing time. The negative voltage zero-crossing time is the instantaneous time when the voltage peak appears in the voltage waveform from the positive direction to the negative direction relative to the zero level, and the positive voltage zero-crossing time is the instantaneous time when the voltage peak appears in the voltage waveform from the negative direction to the positive direction relative to the zero level. The current zero-crossing time includes the negative current zero-crossing time and the positive current zero-crossing time. The negative current zero-crossing time is the instantaneous time when the current peak appears in the current waveform from the positive direction to the negative direction relative to the zero level, and the positive current zero-crossing time is the instantaneous time when the current peak appears in the current waveform from the negative direction to the positive direction relative to the zero level.

[0065] In this embodiment, the negative voltage zero-crossing time refers to the instantaneous time that the voltage waveform passes through the zero level when it changes from the positive direction to the negative direction relative to the zero level after the voltage peak appears. In other words, it is the time point when the voltage changes from a positive value to a negative value and passes through the zero point; the positive voltage zero-crossing time is opposite to the negative voltage zero-crossing time, which refers to the instantaneous time that the voltage waveform passes through the zero level when it changes from the negative direction to the positive direction relative to the zero level after the voltage peak appears (note that the peak here may be negative, but it is "recovering" relative to the next change direction), that is, the time point when the voltage changes from a negative value to a positive value and passes through the zero point.

[0066] The negative current zero-crossing time refers to the instantaneous time when the current waveform passes through the zero current point after the current peak appears (or starts to decrease from a positive value), when it changes from a positive direction to a negative direction relative to the zero current point. In other words, it is the time point when the current changes from a positive value to a negative value and passes through the zero point. The positive current zero-crossing time is opposite to the negative current zero-crossing time. It refers to the instantaneous time when the current waveform passes through the zero current point after the current peak appears (which may be the previous negative peak value, but it "recovers" relative to the next change direction), when it changes from a negative direction to a positive direction relative to the zero current point, that is, the time point when the current changes from a negative value to a positive value and passes through the zero point. This achieves more accurate acquisition of the voltage zero-crossing time and the current zero-crossing time.

[0067] Furthermore, the calculation expression of the phase difference evaluation score is:

[0068] CHA q.n =δ*YAN q.n +γ*WEI q.n +|F1 q.n -F2 q.n |+|Z1 q.n -Z2 q.n |;

[0069] Where q is the number of the segmented sampling point, q = 1, 2, ..., Q, Q is the total number of segmented sampling points, n is the number of the preset sampling period, n = 1, 2, ..., N, N is the total number of preset sampling periods, CHA q.n represents the phase difference evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, δ represents the relative delay evaluation score correction factor, YAN q.n represents the relative delay evaluation score of the segmented waveform in the qth segment sampling point within the nth preset sampling period, γ represents the phase offset evaluation score correction factor, WEI q.n Indicates the phase offset evaluation score of the segmented signal in the nth preset sampling period at the qth segmented sampling point, F1 q.n Indicates the negative voltage zero crossing time of the voltage waveform in the nth preset sampling cycle at the qth segment sampling point, F2 q.n Indicates the negative current zero-crossing time of the current waveform in the nth preset sampling cycle at the qth segment sampling point, Z1 q.n Indicates the positive voltage zero crossing time of the voltage waveform in the nth preset sampling cycle at the qth segment sampling point, Z2 q.n It indicates the positive current zero-crossing time of the current waveform in the nth preset sampling period at the qth segment sampling point.

[0070] In this embodiment, it should be noted that in the calculation formula of the phase difference evaluation score, each preset sampling period here only contains one voltage peak value, valley value and one current peak value, valley value; the specific expression for converting the phase difference evaluation score into the phase angle is: In the formula, JIAO q.n It indicates the phase angle of the segmented waveform in the nth preset sampling period at the qth segment sampling point. The unit is radians. T indicates the preset sampling period. CHA q.n Represents the phase difference evaluation score of the segmented waveform in the nth preset sampling period at the qth segmented sampling point, in radians, where 1 radian ≈ 57.3°.

[0071] It should be understood that the relative delay evaluation score correction factor is obtained from a preset database. In a specific embodiment, a mapping set of relative delay evaluation scores and their corresponding correction factors is constructed based on the relationship between historical relative delay evaluation scores and phase difference evaluation scores in the preset database, and the real-time relative delay evaluation score is input into the mapping set to obtain the corresponding relative delay evaluation score correction factor.

[0072] The phase offset evaluation score correction factor is obtained from a preset database. In a specific embodiment, a mapping set of phase offset evaluation scores and their corresponding correction factors is constructed based on the relationship between historical phase offset evaluation scores and phase difference evaluation scores in the preset database, and the real-time phase offset evaluation score is input into the mapping set to obtain the corresponding phase offset evaluation score correction factor; the correction of the relative delay evaluation score by the relative delay evaluation score correction factor and the correction of the phase offset evaluation score by the phase offset evaluation score correction factor help to improve the accuracy of obtaining the relative delay evaluation score and the phase offset evaluation score, achieve more accurate acquisition of the phase angle, and thus achieve an improvement in the accuracy of phase angle measurement of the segmented smart energy meter, effectively solving the problem of low phase angle measurement accuracy of the segmented smart energy meter in the prior art.

[0073] Further, such as Figure 3As shown, it is a flowchart of abnormal phase angle zero-crossing detection provided by an embodiment of the present application, which converts the phase difference evaluation score into a phase angle and determines whether the phase angle is within a preset phase angle threshold range, and then also includes zero-crossing detection of the abnormal phase angle. The zero-crossing detection is used to detect the zero-crossing point of the voltage signal and the current signal within a preset sampling period. The zero-crossing point indicates that the voltage signal and the current signal pass through the zero level. The specific process of zero-crossing detection is: according to the change of the zero-crossing point of the abnormal phase angle within the preset sampling period, the time interval between adjacent zero-crossing points is recorded in real time and compared with the preset grid frequency. If the time interval between adjacent zero-crossing points is greater than the preset grid frequency, the trigger circuit of the electric energy meter to be tested is recorded as an abnormal circuit, otherwise, the change of the zero-crossing point of the abnormal phase angle within the preset sampling period is continued to be monitored in real time. The abnormal phase angle is a phase angle that is not within the preset phase angle threshold range. The change of the zero-crossing point includes the change of the abnormal phase angle from positive to negative and from negative to positive. The abnormal phase angle is a phase angle that is not within the preset phase angle threshold range; the abnormal fluctuation information of the abnormal circuit is obtained within the preset sampling period and stored in a preset database, and the abnormal fluctuation information includes short-circuit signals and power supply fluctuations.

[0074] In this embodiment, the preset phase angle threshold is usually expressed by summing and averaging the historical phase angles in the preset database. In practical applications, the phase difference between two signals with the same frequency is known. (can be degrees or radians), but usually what we need is the absolute phase angle of a signal Since the phase difference is relative, a reference phase angle (such as the initial phase of a signal or a known phase point) is required to calculate the absolute phase angle. However, in the absence of a specific reference phase angle, we usually only focus on the change in the phase difference. and its phase difference with another signal Then the phase angle of the other signal (or ).

[0075] Specifically, if the phase angle exceeds the threshold range, it is marked as an abnormal phase angle and enters the next step of the zero-crossing detection process: within the preset sampling period, the waveforms of the voltage signal and the current signal are continuously monitored, and a zero-crossing detection algorithm (such as a comparator method) is used to detect when the signal waveform crosses the zero level (i.e., the zero-crossing point), and the time interval T between adjacent zero-crossing points is recorded; based on the time interval T between adjacent zero-crossing points, the actual frequency f=1 / T of the power grid is calculated, and the calculated actual frequency is compared with the preset power grid frequency (such as 50Hz or 60Hz); if the deviation between the actual frequency and the preset power grid frequency exceeds a certain threshold (such as ±0.5%), the power grid frequency is considered to be abnormal, and the trigger circuit of the electric energy meter to be tested is recorded as an abnormal circuit; if the actual frequency is within the preset power grid frequency range, the change of the abnormal phase angle at the zero-crossing point within the preset sampling period is continued to be monitored in real time, thereby improving the accuracy and reliability of the phase angle acquisition of the electric energy meter to be tested.

[0076] To summarize, the embodiment of the present application obtains the sampling data of the electric energy meter to be tested within the preset sampling points and performs segmented processing to obtain the segmented signal, and at the same time inputs the segmented signal within the preset sampling points into the oscilloscope to obtain the segmented waveform and performs filtering processing to obtain the instantaneous voltage value and the instantaneous current value, and then combines the zero-crossing time of the segmented waveform to obtain the phase difference evaluation score and convert it into a phase angle, and at the same time determines whether the phase angle is within the preset phase angle threshold range, thereby achieving an improvement in the accuracy and reliability of obtaining the phase difference evaluation score, and further achieving an improvement in the phase angle measurement accuracy of the segmented smart electric energy meter, effectively solving the problem of low phase angle measurement accuracy of the segmented smart electric energy meter in the prior art.

[0077] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0078] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0079] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0080] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0081] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0082] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for measuring voltage and current phase angles of a segmented smart electric energy meter, characterized in that: The following steps are involved: S1, acquiring sampling data of the electric energy meter to be tested within a preset sampling point and performing segmented processing to obtain a segmented signal, wherein the sampling data includes voltage data and current data, the segmented processing includes a first segmented processing and a second segmented processing, and the segmented signal includes a first segmented signal and a second segmented signal, wherein the first segmented signal is a voltage value after voltage marking within the segmented sampling point, and the second segmented signal is a current value after current marking within the segmented sampling point; S2, inputting the segmented signal within the preset sampling point into the oscilloscope to obtain the segmented waveform, and filtering the obtained segmented waveform to obtain the instantaneous voltage value and the instantaneous current value, wherein the segmented waveform includes a voltage waveform and a current waveform, the instantaneous voltage value is the voltage peak value of the voltage waveform within the preset sampling period, and the instantaneous current value is the current peak value of the current waveform within the preset sampling period; S3, recording the zero-crossing time of the segmented waveform in real time to obtain a phase difference evaluation score, wherein the zero-crossing time includes the voltage zero-crossing time and the current zero-crossing time; S4, converts the phase difference evaluation score into a phase angle and determines whether the phase angle is within a preset phase angle threshold range. If so, it indicates that the electric energy meter to be tested is in a phase balance state within the preset sampling period. Otherwise, returns to S1 until the converted phase angle is within the preset phase angle threshold range.

2. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 1, characterized in that: The specific steps of obtaining the sampling data of the electric energy meter to be tested within the preset sampling points and performing segmented processing are: Converting voltage data into voltage signals and recording voltage amplitude information of the voltage signals at segmented sampling points in real time, wherein the voltage amplitude information is used to reflect the peak and valley values ​​of the voltage signals within a preset sampling period at the segmented sampling points; The current data is converted into a current signal and the current amplitude information of the current signal at the segmented sampling points is recorded in real time. The current amplitude information is used to reflect the peak value and valley value of the current signal within a preset sampling period at the segmented sampling points.

3. A segmented smart energy meter voltage and current phase angle measurement method as claimed in claim 2, characterized in that: The step of obtaining the segmented signal further includes obtaining a phase shift evaluation score according to the obtained voltage amplitude information and current amplitude information, wherein the phase shift evaluation score is used to measure the phase deviation degree of the current signal and the voltage signal at the segmented sampling point within the same timestamp. The specific method is as follows: The number of peak values ​​and valley values ​​of the current signal and the voltage signal in the same timestamp within a preset sampling period are recorded in real time, and the voltage timestamp and the current timestamp are combined to obtain a phase shift evaluation score. The voltage timestamp represents the time period when the voltage signal reaches the peak value from the valley value within the preset sampling period, and the current timestamp represents the time period when the current signal reaches the peak value from the valley value within the preset sampling period.

4. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 3, characterized in that: The phase shift evaluation score is calculated using the following formula: Where q is the number of the segmented sampling point, q = 1, 2, ..., Q, Q is the total number of segmented sampling points, n is the number of the preset sampling period, n = 1, 2, ..., N, N is the total number of preset sampling periods, e is a natural constant, WEI q.n A1 represents the phase offset evaluation score of the segmented signal in the nth preset sampling period at the qth segmented sampling point. q.n Indicates the number of peak values ​​of the voltage signal in the nth preset sampling period at the qth segment sampling point, B1 q.n A2 represents the number of peak values ​​of the current signal in the nth preset sampling period at the qth segment sampling point. q.n Indicates the number of valley values ​​of the voltage signal in the nth preset sampling period at the qth segment sampling point, B2 q.n Indicates the number of valley values ​​of the current signal in the nth preset sampling period at the qth segment sampling point, A3 q.n Indicates the voltage timestamp of the voltage signal in the nth preset sampling period at the qth segment sampling point, B3 q.n Indicates the current timestamp of the current signal in the nth preset sampling period at the qth segment sampling point.

5. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 4, characterized in that: The filtering process of the acquired segmented waveform also includes real-time monitoring of harmonics in the segmented waveform to obtain a harmonic distortion evaluation score, wherein the harmonic distortion evaluation score is used to measure the influence of the harmonic component on the segmented waveform. The specific steps are as follows: Converting the time domain signal in the segmented waveform into a frequency domain signal by Fourier transform to obtain the fundamental signal amplitude and the harmonic signal amplitude, wherein the frequency domain signal is used to reflect the frequency distribution of the fundamental signal and the harmonic signal in the segmented waveform, wherein the fundamental signal amplitude includes the voltage fundamental signal amplitude and the current fundamental signal amplitude, and the harmonic signal amplitude includes the voltage harmonic signal amplitude and the current harmonic signal amplitude; The duration of the voltage harmonic signal amplitude and the current harmonic signal amplitude within the preset sampling period is recorded in real time, and the harmonic distortion evaluation score is obtained by combining the acquired phase shift evaluation score, fundamental signal amplitude and harmonic signal amplitude.

6. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 5, characterized in that: The harmonic distortion evaluation score is calculated using the following formula: In the formula, XIE q.n Indicates the harmonic distortion evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, C1 q.n Indicates the voltage harmonic signal amplitude of the voltage waveform in the nth preset sampling period at the qth segment sampling point, D1 q.n Indicates the voltage fundamental signal amplitude of the voltage waveform in the nth preset sampling period at the qth segment sampling point, C2 q.n Indicates the duration of the voltage harmonic signal amplitude at the qth segment sampling point of the voltage waveform within the nth preset sampling period, C3 q.n Indicates the duration of the current harmonic signal amplitude in the nth preset sampling period at the qth segment sampling point of the current waveform, D2 q.n Indicates the duration of the fundamental signal amplitude in the nth preset sampling period at the qth segment sampling point, C4 q.n Indicates the current harmonic signal amplitude of the current waveform in the nth preset sampling period at the qth segment sampling point, D3 q.n It represents the amplitude of the current fundamental wave signal of the current waveform in the nth preset sampling period at the qth segment sampling point.

7. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 6, characterized in that: The real-time recording of the zero-crossing time of the segmented waveform also includes obtaining a relative delay evaluation score according to the obtained instantaneous voltage value and instantaneous current value, wherein the relative delay evaluation score is used to reflect the deviation between the voltage waveform and the current waveform, and the relative delay evaluation score is calculated by the following formula: In the formula, YAN q.n Represents the relative delay evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, P1 q.n It represents the instantaneous voltage value of the voltage waveform in the nth preset sampling period at the qth segment sampling point, P20 represents the reference instantaneous voltage value, ΔP represents the instantaneous voltage value reference deviation, Q1 q.n represents the instantaneous current value of the current waveform in the nth preset sampling period at the qth segment sampling point, Q20 represents the reference instantaneous current value, ΔQ represents the instantaneous current value reference deviation, XIE0 represents the reference harmonic distortion evaluation score, and ΔXIE represents the harmonic distortion evaluation score reference deviation.

8. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 1, characterized in that: The voltage zero-crossing time includes a negative voltage zero-crossing time and a positive voltage zero-crossing time, and the current zero-crossing time includes a negative current zero-crossing time and a positive current zero-crossing time.

9. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 8, characterized in that: The calculation expression of the phase difference evaluation score is: NO q.n =δ*THAT q.n +γ*WEI q.n +|F1 q.n -F2 q.n |+|Z1 q.n -Z2 q.n |? Where q is the number of the segmented sampling point, q = 1, 2, ..., Q, Q is the total number of segmented sampling points, n is the number of the preset sampling period, n = 1, 2, ..., N, N is the total number of preset sampling periods, CHA q.n represents the phase difference evaluation score of the segmented waveform in the nth preset sampling period at the qth segment sampling point, δ represents the relative delay evaluation score correction factor, YAN q.n represents the relative delay evaluation score of the segmented waveform in the qth segment sampling point within the nth preset sampling period, γ represents the phase offset evaluation score correction factor, WEI q.n Indicates the phase offset evaluation score of the segmented signal in the nth preset sampling period at the qth segmented sampling point, F1 q.n Indicates the negative voltage zero crossing time of the voltage waveform in the nth preset sampling cycle at the qth segment sampling point, F2 q.n Indicates the negative current zero-crossing time of the current waveform in the nth preset sampling cycle at the qth segment sampling point, Z1 q.n Indicates the positive voltage zero crossing time of the voltage waveform in the nth preset sampling cycle at the qth segment sampling point, Z2 q.n It indicates the positive current zero-crossing time of the current waveform in the nth preset sampling period at the qth segment sampling point.

10. A method for measuring voltage and current phase angles of a segmented smart electric energy meter as claimed in claim 1, characterized in that: The phase difference evaluation score is converted into a phase angle and whether the phase angle is within a preset phase angle threshold range is determined, and then a zero-crossing detection is performed on the abnormal phase angle. The specific process of the zero-crossing detection is as follows: According to the change of the zero-crossing point of the abnormal phase angle within the preset sampling period, the time interval between adjacent zero-crossing points is recorded in real time and compared with the preset grid frequency. If the time interval between adjacent zero-crossing points is greater than the preset grid frequency, the trigger circuit of the electric energy meter to be tested is recorded as an abnormal circuit, otherwise, the change of the zero-crossing point of the abnormal phase angle within the preset sampling period is continued to be monitored in real time; Abnormal fluctuation information of the abnormal circuit is acquired within a preset sampling period and stored in a preset database, wherein the abnormal fluctuation information includes a short circuit signal and a power supply fluctuation.

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