Method and system for calibrating power quality monitoring equipment in power distribution area

Abstract

The invention discloses a verification method and system for power quality monitoring equipment in a power distribution area. The method comprises the steps of determining an optimal modulation frequency based on obtained signal parameter information, generating standard characteristic value sequences corresponding to 10 cycles and 150 cycles for power quality verification within a preset time interval based on the optimal modulation frequency, obtaining a 10-cycle actual measurement value sequence and a 150-cycle actual measurement value sequence actually output by an EUT, and calculating the power quality of the EUT according to the obtained 10-cycle actual measurement value sequence and the 150-cycle actual measurement value sequence. Determining actual characteristic value sequences respectively corresponding to the 10-cycle wave measured value sequence and the 150-cycle wave measured value sequence; and determining a verification result based on the standard eigenvalue sequence and the actual eigenvalue sequence. According to the embodiment of the invention, by determining the optimal modulation frequency, generating the corresponding standard eigenvalue sequence based on the optimal modulation frequency and determining the verification result based on the standard eigenvalue sequence and the actual eigenvalue sequence, whether the sampling value is omitted or reused and whether the 10-cycle value is omitted or reused can be verified; and the verification accuracy and precision are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power quality verification, and in particular to a verification method and system for power quality monitoring equipment in a distribution station area. Background Art

[0002] In recent years, photovoltaic power generation has been widely used in various places. This power generation method first converts the direct current of the photovoltaic panels into alternating current, and then transmits it in parallel to the main power grid. During the grid connection process, some low-voltage distribution stations sometimes burn out transformers and damage electrical equipment. Therefore, it is necessary to effectively monitor, analyze and measure the quality of the electricity provided by this type of photovoltaic power source in order to better develop photovoltaic technology and investigate accidents.

[0003] In some current solutions, the calibration system superimposes harmonics with varying amplitudes on the voltage fundamental wave. However, since rectangular waves are used to modulate harmonics and the modulation period is greater than 10 cycles, it is possible to use one '10-cycle measurement value' to replace several '10-cycle measurement values'. For example, if the modulation frequency is 3 seconds and the duty cycle is 1:3, the amplitudes of the signals in the first 1 second and the last 2 seconds are different, but they are both steady-state signals. In this case, there may also be gap measurements. If this '10-cycle value' is used to perform overvoltage and undervoltage analysis, the goal may not be achieved. In the actual operating environment of power quality detection equipment, the monitored voltage signal is not a steady-state signal, but a complex, variable, and gradual signal. If gap measurement or slip measurement is used, the measurement data cannot reflect the actual voltage signal conditions in each time period, thereby greatly reducing the accuracy and precision of the calibration. Summary of the invention

[0004] In view of this, the present invention provides a calibration method and system for power quality monitoring equipment in a distribution station area, which can identify whether sampling values ​​are omitted or reused and whether 10-cycle values ​​are omitted or reused, thereby improving the accuracy and precision of the calibration.

[0005] According to one aspect of the present invention, an embodiment of the present invention provides a method for calibrating power quality monitoring equipment in a distribution station area, the method comprising:

[0006] Acquire signal parameter information of a preconfigured three-phase voltage signal, and determine an optimal modulation frequency based on the signal parameter information;

[0007] Generate standard characteristic value sequences corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality verification within a preset time interval based on the optimal modulation frequency;

[0008] Obtain a 10-cycle measured value sequence and a 150-cycle measured value sequence actually output by the power quality monitoring device EUT, and determine actual characteristic value sequences corresponding to the 10-cycle measured value sequence and the 150-cycle measured value sequence respectively;

[0009] Based on the standard characteristic value sequence and the actual characteristic value sequence, the verification result of the actual verification signal measurement result output by the power quality monitoring equipment in the distribution station area is determined, and the verification result is used to generate a verification report.

[0010] According to another aspect of the present invention, an embodiment of the present invention further provides a verification system for power quality monitoring equipment in a distribution station area, characterized in that the system comprises: a program-controlled power source, a power quality monitoring equipment EUT, a clock source and a host computer;

[0011] Wherein, the program-controlled power source is used to receive the configuration instructions of the signal parameter information of the host computer and output a three-phase voltage signal to the EUT;

[0012] The EUT is used to receive a three-phase voltage signal, obtain an actual verification signal of a signal source, and transmit the measurement results of the three-phase voltage signal and the actual verification signal to the host computer; wherein the three-phase voltage signal and the actual verification signal correspond to corresponding signal parameter information respectively;

[0013] The host computer is used to execute the verification method of the power quality monitoring equipment in the distribution station area as described in any one of the embodiments of the present invention;

[0014] The clock source is used to periodically output a stable and accurate time signal to synchronize the time of the programmable power source with the clock source, and the time of the EUT with the clock source.

[0015] The technical solution of the embodiment of the present invention determines the optimal modulation frequency based on the acquired signal parameter information, so that the modulation signal characteristics can be made more obvious. The optimal modulation frequency can design three signals: fundamental modulation signal, harmonic modulation signal, and interharmonic modulation signal for subsequent verification; based on the optimal modulation frequency, a standard characteristic value sequence corresponding to 10-cycle values ​​and 150-cycle values ​​for power quality verification within a preset time interval is generated, and the actual measured value sequence of every 10 cycles and the actual measured value sequence of 150 cycles of the EUT actual output are obtained, and the actual measured value sequence of every 10 cycles is determined. And the actual characteristic value sequence corresponding to the 150-cycle measured value sequence respectively, and the calibration result of the actual calibration signal measurement result output by the power quality monitoring equipment in the distribution station area is determined based on the standard characteristic value sequence and the actual characteristic value sequence. By matching the standard characteristic value sequence with the actual characteristic value sequence, various calibration anomalies can be identified to calibrate whether the sampling value is omitted or reused and whether the 10-cycle value is omitted or reused. Whether the 150-cycle value is omitted or reused can be inferred through the 10-cycle value, thereby improving the accuracy of the calibration, which is facilitating data analysis, accident investigation and use.

[0016] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A flow chart of a method for calibrating power quality monitoring equipment in a distribution station area provided by an embodiment of the present invention;

[0019] Figure 2 A schematic diagram of a fundamental wave modulation signal waveform provided by an embodiment of the present invention;

[0020] Figure 3 A schematic diagram of a 10-cycle effective value change provided by an embodiment of the present invention;

[0021] Figure 4 A flow chart of another method for calibrating power quality monitoring equipment in a distribution station area provided by an embodiment of the present invention;

[0022] Figure 5 A flow chart for determining an optimal modulation frequency provided by an embodiment of the present invention;

[0023] Figure 6 A Q value of a voltage effective value sequence provided by an embodiment of the present invention;

[0024] Figure 7 A flow chart for detecting abnormal measurement of 10-cycle value provided by an embodiment of the present invention;

[0025] Figure 8 A flow chart of the detection of abnormal 150-cycle value measurement provided by an embodiment of the present invention;

[0026] Fig. 9 A structural block diagram of a verification system for power quality monitoring equipment in a distribution station area provided by an embodiment of the present invention;

[0027] Fig.10 A schematic diagram of the overlap of 10-cycle and 150-cycle power quality parameters provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] In one embodiment, Figure 1 A flowchart of a calibration method for power quality monitoring equipment in a distribution station area provided in one embodiment of the present invention. This embodiment is applicable to the situation when calibrating power quality monitoring equipment in a distribution station area. The method can be executed by a host computer in the calibration system of the power quality monitoring equipment in the distribution station area.

[0031] like Figure 1As shown, the verification method of the power quality monitoring equipment in the distribution station area in this embodiment specifically includes the following steps:

[0032] S110. Acquire signal parameter information of a preconfigured three-phase voltage signal, and determine an optimal modulation frequency based on the signal parameter information.

[0033] Among them, the signal parameter information includes at least one of the following: fundamental frequency, fundamental amplitude, harmonic amplitude, harmonic number, harmonic frequency, interharmonic amplitude, interharmonic number, interharmonic frequency, modulation depth, the number of sampled values ​​within a 10-cycle measurement period, and the time value of each sampled value. In addition, it can also include sampling time intervals, etc. In this embodiment, the signal parameter information of the three-phase voltage signal is pre-configured parameter information, and different configuration parameters can produce different voltage waveforms. Exemplarily, the fundamental amplitude is set to 100, the harmonic number is set to 14, the modulation depth is set to 0.2, the number of sampled values ​​within a 10-cycle measurement period is 256, etc., which can be configured according to requirements. In this embodiment, 1 cycle can correspond to multiple continuous sampling values ​​of time scale values, 10 continuous 1-cycle sampling values ​​can form 10 cycles, and 15 10 cycles can synthesize 150 cycles.

[0034] In this embodiment, the signal parameter information of the three-phase voltage signal pre-configured for calibrating the power quality monitoring equipment of the distribution station area is obtained to determine the optimal modulation frequency through parameters such as fundamental frequency, fundamental amplitude, harmonic amplitude, harmonic order, harmonic frequency, interharmonic amplitude, interharmonic order, interharmonic frequency, modulation depth, the number of sampling values ​​within a 10-cycle measurement period, and the time value of each sampling value. In some embodiments, a modulation frequency can be randomly selected from the preset modulation frequencies as the current modulation frequency, and the modulation signal corresponding to the current modulation frequency is determined. The fundamental modulation signal is constructed by the modulation signal and the fundamental signal. Based on the fundamental modulation signal, the sampling values ​​in each 10-cycle time period are used to deduce the voltage effective value sequence, the harmonic value sequence, and the interharmonic value sequence to identify the power quality characteristics of the voltage signal every 10 cycles; the 10-cycle voltage effective value sequence is subjected to a Fast Fourier Transform (FFT) (Fast Fourier Transform) Transformation) analysis is performed to obtain the analysis result, the time domain signal is transformed into the frequency domain to obtain the corresponding spectrum, the spectrum point with the largest power spectrum density is selected from the analysis result to perform energy enhancement calculation to obtain the corresponding enhancement value, on this basis, the first 10-cycle effective value in the 10-cycle effective value sequence is modified, that is, the abnormal 10-cycle effective value sequence with one sample value omitted, the abnormal 10-cycle effective value sequence is subjected to FFT analysis, the spectrum point with the largest power spectrum density is selected to perform energy enhancement calculation to obtain the corresponding enhancement value, the enhancement value is calculated for the unmodified 10-cycle voltage effective value sequence, and the enhancement value is calculated for the modified 10-cycle voltage effective value sequence to obtain the optimal modulation frequency. In other embodiments, an attribute table containing the modulation frequency can be configured to determine the characteristics of the required optimal modulation frequency, and the corresponding modulation frequency is selected as the optimal modulation frequency based on the attribute table and the characteristics. Of course, the method for determining the optimal modulation frequency can also be other methods, which are not limited in this embodiment.

[0035] S120, generating standard characteristic value sequences corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality verification within a preset time interval based on the optimal modulation frequency.

[0036] The preset time interval may be 10 minutes each, or may be a time interval set according to demand. For example, the preset time interval may be set from 0:10 to 0:20, but this embodiment does not impose any limitation on this.

[0037] In this embodiment, the standard characteristic value sequence includes multiple standard characteristic values, and each standard characteristic value corresponds to a corresponding test value and time scale. Each 10-cycle wave corresponds to a corresponding 10-cycle standard characteristic value sequence, and every 15 10-cycle waves can be aggregated into a 150-cycle wave, and each 150-cycle wave also corresponds to a corresponding standard characteristic value sequence. Among them, the standard characteristic values ​​include: a 10-cycle value sequence (also referred to as a cyc10 value sequence), an enhanced value of a 10-cycle value sequence (also referred to as a Q_Cyc10 value sequence), a 10-cycle overlapping value, and an enhanced value of a 10-cycle overlapping value; a 150-cycle value sequence, an enhanced value of a 150-cycle value sequence, a 150-cycle overlapping value, and an enhanced value of a 150-cycle overlapping value.Among them, the 10-cycle value sequence includes a 10-cycle effective value sequence (also known as S_Cyc10_bm), a 10-cycle harmonic value sequence (also known as S_Cyc10_hm), and a 10-cycle interharmonic value sequence (also known as S_Cyc10_im); the 150-cycle value sequence includes: a 150-cycle effective value sequence (also known as S_Sec3_bm), a 150-cycle harmonic value sequence (also known as S_Sec3_hm), and a 150-cycle interharmonic value sequence (also known as S_Sec3_im); the enhanced values ​​of the 10-cycle value sequence include: a 10-cycle effective value sequence (also known as S_Sec3_bm), a 150-cycle harmonic value sequence (also known as S_Sec3_hm), and a 150-cycle interharmonic value sequence (also known as S_Sec3_im); the enhanced values ​​of the 10-cycle value sequence include: The enhanced value of the 10-cycle effective value sequence (also called Q_Cyc10_bm), the enhanced value of the 10-cycle harmonic value sequence (also called Q_Cyc10_hm), and the enhanced value of the 10-cycle interharmonic value sequence (also called Q_Cyc10_im); the enhanced value of the 150-cycle value sequence includes: the enhanced value of the 150-cycle effective value sequence (also called Q_Sec3_bm), the enhanced value of the 150-cycle harmonic value sequence (also called Q_Sec3_hm), and the enhanced value of the 150-cycle interharmonic value sequence (also called Q_Sec3_im); the 10-cycle value sequence includes: the enhanced value of the 150-cycle effective value sequence (also called Q_Sec3_bm), the enhanced value of the 150-cycle harmonic value sequence (also called Q_Sec3_hm), and the enhanced value of the 150-cycle interharmonic value sequence (also called Q_Sec3_im); The overlapping values ​​include: 10-cycle effective value overlapping value (also called Cyc10_bmZ), 10-cycle harmonic value overlapping value (also called Cyc10_hmZ), 10-cycle interharmonic value overlapping value (also called Cyc10_imZ); 150-cycle overlapping value: 150-cycle effective value overlapping value (also called Sec3_bmZ), 150-cycle harmonic value overlapping value (also called Sec3_hmZ), 150-cycle interharmonic value overlapping value (also called Sec3_imZ); The enhanced value of the 10-cycle overlapping value includes: 10-cycle effective value overlapping value Enhanced value (also known as Q_Cyc10_bmZ), overlapping value enhancement value of 10-cycle harmonic value (also known as Q_Cyc10_hmZ), overlapping value enhancement value of 10-cycle interharmonic value (also known as Q_Cyc10_imZ); The enhanced value of 150-cycle overlapping value includes: overlapping value enhancement value of 150-cycle effective value (also known as Q_Sec3_bmZ), overlapping value enhancement value of 150-cycle harmonic value (also known as Q_Sec3_hmZ), overlapping value enhancement value of 150-cycle interharmonic value (also known as Q_Sec3_imZ).

[0038] In this embodiment, since the standard characteristic value includes multiple characteristic values, the standard characteristic value sequences corresponding to 10 cycles and 150 cycles for power quality verification within the preset time interval can be generated in different ways. In some embodiments, the optimal modulation frequency is used to construct the fundamental modulation signal, the harmonic modulation signal and the interharmonic modulation signal, and the 10-cycle effective value sequence within the preset time interval is obtained by the 10-cycle effective value corresponding to the fundamental modulation signal and at least two 10 cycles within the preset time interval. Every 15 10 cycles can be aggregated to obtain a 150-cycle, and the 15 10-cycle effective value sequences contained in the preset time interval can be aggregated to obtain a 150-cycle effective value sequence; similarly, the calculation of the 10-cycle harmonic value sequence, the 150-cycle harmonic value sequence, the 10-cycle interharmonic value sequence, and the 150-cycle interharmonic value sequence can be determined in the same way. It should be noted that each sequence includes a corresponding value and a time stamp, and the time stamp can characterize the time when the value is generated. Specifically, the 10-cycle effective value sequence includes effective values ​​and time scales corresponding to the effective values, the 150-cycle effective value sequence includes effective values ​​and time scales corresponding to the effective values, etc. In some embodiments, the 10-cycle harmonic value sequence, the 10-cycle interharmonic value sequence, the 150-cycle interharmonic value sequence, and the 150-cycle harmonic value sequence can be subjected to FFT analysis respectively, and the amplitude of each frequency point and the enhancement value of each frequency point can be calculated to obtain the enhancement value of the 10-cycle effective value sequence, the enhancement value of the 10-cycle harmonic value sequence, and the enhancement value of the 10-cycle interharmonic value sequence; the 150-cycle effective value sequence, the 150-cycle harmonic value sequence, and the 150-cycle interharmonic value sequence obtained by aggregation can be input into the function Q_rms_max for FFT analysis, thereby obtaining the enhancement value of the 150-cycle effective value sequence, the enhancement value of the 150-cycle harmonic value sequence, and the enhancement value of the 150-cycle interharmonic value sequence. In this embodiment, the function of the function Q_rms_max is to calculate the enhancement value of the sequence.

[0039] In other embodiments, the number of 10-cycle value sequences within a preset time interval can be calculated, and the Nth value contained in the number is used as the 10-cycle overlap value; for the calculation of the 150-cycle overlap value, a certain number of 10-cycle values ​​can be divided into a group for calculating the 150-cycle value. Since there may be a situation where the number of 10-cycle values ​​is not enough to form a group, the number of 10-cycle values ​​in the last group can be recorded as the first number of 10-cycle values, and the second number of 10-cycle values ​​can be selected from the 10-cycle value sequence starting from the second preset time. The first number of 10-cycle value sequences and the second number of 10-cycle value sequences are combined into a target 10-cycle value sequence in order and FFT analysis is performed to calculate the overlap value enhancement value of the effective value corresponding to the 10 cycles, the overlap value enhancement value of the harmonic value, and the overlap value enhancement value of the interharmonic value. Of course, the 10-cycle overlap value and the 150-cycle overlap value can also be determined in other ways, and this embodiment is not limited here.

[0040] S130, obtaining a 10-cycle measured value sequence and a 150-cycle measured value sequence corresponding to the actual verification signal actually output by the EUT, and determining the actual characteristic value sequences corresponding to the 10-cycle measured value sequence and the 150-cycle measured value sequence respectively.

[0041] Among them, the power quality monitoring equipment (Equipment Under Test, EUT) can also be called the device under test or the device under test, which refers to the device under test for receiving, detecting and measuring the actual signal. The device under test can output a 10-cycle measured value sequence and a 150-cycle measured value sequence corresponding to the actual signal. In this embodiment, the 10-cycle measured value sequence includes one or more 10-cycle measured values, and the 150-cycle measured value sequence includes one or more 150-cycle measured values; wherein, a '150-cycle measured value' is synthesized by 15 '10-cycle measured values' that are continuous in time, and each '150-cycle measured value' in the '150-cycle measured value' sequence is also continuous.

[0042] In this embodiment, the actual characteristic value sequence includes: an actual 10-cycle value sequence, an enhanced value of the actual 10-cycle value sequence, an actual 10-cycle overlap value, and an enhanced value of the actual 10-cycle overlap value; an actual 150-cycle value sequence, an enhanced value of the actual 150-cycle value sequence, an actual 150-cycle overlap value, and an enhanced value of the actual 150-cycle overlap value; similarly, the actual 10-cycle value sequence includes: an actual 10-cycle effective value sequence, an actual 10-cycle harmonic value sequence, and an actual 10-cycle interharmonic value sequence; the actual 150-cycle value sequence includes: an actual 150-cycle effective value sequence, an actual 150-cycle harmonic value sequence, and an actual 150-cycle interharmonic value sequence; the actual 10-cycle overlap value includes: an actual The actual 10-cycle effective value overlap value, the actual 10-cycle harmonic value overlap value, and the actual 10-cycle inter-harmonic value overlap value; the actual 150-cycle overlapping value includes: the actual 150-cycle effective value overlap value, the actual 150-cycle harmonic value overlap value, and the actual 150-cycle inter-harmonic value overlap value; the enhanced value of the actual 10-cycle overlapping value includes: the enhanced value of the overlapping value of the actual 10-cycle effective value, the enhanced value of the overlapping value of the actual 10-cycle harmonic value, and the enhanced value of the overlapping value of the actual 10-cycle inter-harmonic value; the enhanced value of the actual 150-cycle overlapping value includes: the enhanced value of the overlapping value of the actual 150-cycle effective value, the enhanced value of the overlapping value of the actual 150-cycle harmonic value, and the enhanced value of the overlapping value of the actual 150-cycle inter-harmonic value.

[0043] In this embodiment, the method for calculating the enhancement value of the actual 10-cycle value sequence, the enhancement value of the actual 10-cycle overlapping value, the enhancement value of the actual 150-cycle value sequence, and the enhancement value of the actual 150-cycle overlapping value is the same as the method for calculating the enhancement value in the standard characteristic value, and this embodiment will not be described in detail here.

[0044] In this embodiment, the actual output of the substation can be obtained from the power quality monitoring equipment EUT. The actual characteristic value sequence corresponding to each 10-cycle measured value sequence and the 150-cycle measured value sequence is determined for the subsequent verification process. In some embodiments, since the 10-cycle measured value sequence includes: an actual 10-cycle effective value sequence, an actual 10-cycle harmonic value sequence, and an actual 10-cycle interharmonic value sequence, when calculating the enhanced value of the actual 10-cycle value sequence, the actual 10-cycle effective value sequence, the actual 10-cycle harmonic value sequence, and the actual 10-cycle interharmonic value sequence can be FFT analyzed respectively, and the amplitude of each frequency point and the enhanced value of each frequency point are calculated, thereby obtaining the overlap value enhancement value of the actual 10-cycle effective value, the overlap value enhancement value of the actual 10-cycle harmonic value, and the overlap value enhancement value of the actual 10-cycle interharmonic value. Therefore, by performing FFT analysis on the actual 150-cycle effective value sequence, the actual 150-cycle harmonic value sequence, and the actual 150-cycle interharmonic value sequence obtained by aggregation, the overlapping value enhancement value of the actual 150-cycle effective value, the overlapping value enhancement value of the actual 150-cycle harmonic value, and the overlapping value enhancement value of the actual 150-cycle interharmonic value can be obtained.

[0045] S140. Determine the calibration result of the actual calibration signal measurement result output by the power quality monitoring equipment in the distribution station area based on the standard eigenvalue sequence and the actual eigenvalue sequence, and generate a calibration report based on the calibration result.

[0046] The actual test signal measurement result can be understood as the measurement result obtained by comparing the standard characteristic value sequence with the actual characteristic value sequence. The test result is the test result of normal test or abnormal test. Of course, the abnormal test in the test result can include one or more abnormalities.

[0047] In this embodiment, the 10-cycle value sequence, the enhanced value of the 10-cycle value sequence, the 10-cycle overlap value, the enhanced value of the 10-cycle overlap value, the 150-cycle value sequence, the enhanced value of the 150-cycle value sequence, the 150-cycle overlap value, and the enhanced value of the 150-cycle overlap value in the standard characteristic value sequence can be compared with the actual 10-cycle value sequence, the enhanced value of the actual 10-cycle value sequence, the enhanced value of the actual 10-cycle overlap value, the enhanced value of the actual 10-cycle overlap value, the actual 150-cycle value sequence, the enhanced value of the actual 150-cycle value sequence, the actual 150-cycle overlap value, and the enhanced value of the actual 150-cycle overlap value in the actual characteristic value sequence, respectively, to determine the calibration result of the actual calibration signal measurement result output by the power quality monitoring equipment in the distribution station area. The detection result can generate a corresponding detection report, which may include abnormal situations such as whether overlap occurs within a preset time interval and whether omission occurs. Since each sequence corresponds to a corresponding value and time stamp, in addition to the abnormality, the precise source and time point of the abnormality can also be given. In other embodiments, after performing the comparison, the error between the standard eigenvalue sequence and the actual eigenvalue sequence can be calculated, and it can be determined whether the error between the standard eigenvalue sequence and the actual eigenvalue sequence exceeds the standard, and then the calculation result and the judgment result can be output to generate a test report, which is not limited in this embodiment.

[0048] The technical solution of the embodiment of the present invention determines the optimal modulation frequency based on the acquired signal parameter information, so that the modulation signal characteristics can be more obvious. The optimal modulation frequency can design three signals, namely, fundamental modulation signal, harmonic modulation signal, and interharmonic modulation signal, for subsequent verification; based on the optimal modulation frequency, a standard characteristic value sequence corresponding to 10 cycles and 150 cycles for power quality verification within a preset time interval is generated, and the actual measured value sequence of each 10 cycles and the actual measured value sequence of 150 cycles of the EUT actual output is obtained, and the actual characteristic value sequence corresponding to each 10-cycle measured value sequence and the actual characteristic value sequence of 150 cycles is determined. The verification result of the actual verification signal measurement result output by the power quality monitoring equipment in the distribution station area is determined based on the standard characteristic value sequence and the actual characteristic value sequence. By matching the standard characteristic value sequence with the actual characteristic value sequence, various verification anomalies can be identified, such as whether the sampling value is omitted or reused and whether the 10-cycle value is omitted or reused, thereby improving the accuracy of the verification, which is beneficial to data analysis, accident investigation and use.

[0049] In general, the minimum granularity of harmonic frequency is an integer multiple of the fundamental frequency, and the minimum granularity of interharmonic frequency is 0.1 times the fundamental frequency, so the number of harmonics and interharmonics in any 10 cycles is the same and an integer, which also means that the effective value, harmonic value, and interharmonic value of any 10 cycles are also the same. Therefore, for the 150-cycle aggregate value, one or several 10-cycle values ​​may be used to replace it, because the result of aggregating any 10-cycle values ​​is the same, but in actual operation on site, the voltage signal is complex and changeable, and the fundamental amplitude, harmonic amplitude, and interharmonic amplitude are often time-varying. Therefore, the power quality monitoring equipment should strictly implement the standard regulations, and the verification system should also have the following capabilities: it can identify whether the sampling value is missed during the sampling process and whether the sampling value is reused; it can detect whether the 10-cycle value is missed when aggregating the 150-cycle value and whether the 10-cycle value is reused. To this end, we should go beyond the standard agreement and make each 10-cycle value of the calibration signal change and be different within a longer period of time, and then do in-depth analysis and testing on this basis.

[0050] Figure 2 A schematic diagram of a fundamental wave modulation waveform provided by an embodiment of the present invention, Figure 3 A schematic diagram of a 10-cycle effective value change provided by an embodiment of the present invention. In this embodiment, in order to change the effective value of cyc10, a method is proposed to linearly modulate the fundamental wave, which can be expressed as

[0051] S_bm(t)=V_b×sin(2π×F_b×t)×(1.0+A_m×sin(2π×F_m×t+J_m)). When V_b=100V, F_b=50.58Hz, F_m=1.2645Hz, A_m=20%, and time t is from 0 to 1.977066 seconds, the waveform of S_bm is as follows: Figure 2 As shown, within the time from 0 to 1.977066 seconds, there are 10 cyc10 values ​​(the cyc10 value can be a 10-cycle effective value, a 10-cycle harmonic value, or a 10-cycle interharmonic value). The waveform diagram of the change of the 10-cycle effective value is as follows Figure 3As shown; it can be seen that the change cycle of the cyc10 value and the modulation frequency are basically synchronized (it changes about 2×1.2645=2.529 times in 2 seconds). One way to detect this change is to perform filtering analysis and FFT calculation on a set of continuous cyc10 values, and analyze the spectrum in the calculation results. If the cyc10 value sequence changes periodically, then there is a frequency point in the spectrum of the FFT calculation result that has greater energy than other frequency points. As for how to choose the modulation frequency, the analysis is as follows: the cyc10 duration (10-cycle time period) is about 0.2 seconds, the cycle of the cyc10 value sequence must be greater than 0.2 seconds, and the change frequency must be less than 5Hz. According to the Nyquist sampling theorem, the sampling frequency should be greater than 2 times the signal frequency, otherwise there will be a spectrum aliasing effect. The cyc10 value sequence is equivalent to sampling the change envelope of the modulation wave, and the sampling rate is about 5Hz, so the modulation frequency must be less than 2.5Hz to meet the relationship between the cyc10 value change frequency and the sampling rate, so that the FFT analysis is effective. Therefore, an optimal modulation frequency method is designed to satisfy the relationship between the cyc10 value change frequency and the sampling rate.

[0052] In one embodiment, Figure 4 A flowchart of another method for calibrating power quality monitoring equipment in a distribution station area provided for an embodiment of the present invention. Based on the above embodiments, this embodiment further refines the method for obtaining signal parameter information of a preconfigured three-phase voltage signal and determining the optimal modulation frequency based on the signal parameter information; and generating standard characteristic value sequences corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality calibration within a preset time interval based on the optimal modulation frequency.

[0053] like Figure 4 As shown, the verification method of the power quality monitoring equipment in the distribution station area in this embodiment may specifically include the following steps:

[0054] S410. Obtain signal parameter information of a preconfigured three-phase voltage signal.

[0055] S420, construct a fundamental wave signal according to the number of sampling values ​​in each 10-cycle measurement period and the time value, fundamental wave amplitude and fundamental wave frequency of each sampling value, and randomly select a modulation frequency from the preset modulation frequencies as the current modulation frequency; wherein the preset modulation frequency is constructed from the fundamental wave frequency.

[0056] Among them, the 10-cycle measurement cycle means that every 10 cycles is a measurement cycle. For each 10 cycles, there are corresponding sampling values ​​and sampling times. For example, there are a total of 128 10 cycles, 256 sampling values ​​per cycle, each sampling value corresponds to a corresponding time value, and the sampling interval is 0.000078125 seconds, then 128 10 cycles have a total of 327680 sampling values.

[0057] In this embodiment, a preset modulation frequency is obtained by constructing the fundamental frequency, and the optimal modulation frequency is searched from the preset modulation frequencies, and the optimal modulation frequency corresponds to the corresponding fundamental frequency. In this embodiment, for each 10 cycles within the preset time length, the fundamental signal is constructed according to the number of sampling values ​​in each 10-cycle measurement period and the time value, fundamental amplitude and fundamental frequency of each sampling value, and a modulation frequency is randomly selected from the preset modulation frequencies as the current modulation frequency, and the optimal modulation frequency is searched from the preset modulation frequencies in an iterative cycle.

[0058] S430, determining a modulation signal corresponding to the current modulation frequency, and constructing a fundamental wave modulation signal from the modulation signal and the fundamental wave signal.

[0059] In this embodiment, the modulation signal can be constructed by the current modulation frequency, modulation amplitude and the time value of each sampling value, and the modulation signal and the fundamental wave signal are multiplied to obtain the fundamental wave modulation signal. Exemplarily, the relationship between the fundamental wave frequency and the preset modulation frequency is expressed as: F_m = F_m_no × 1.0 / (n128 × (10 × 1.0 / F_b)), where F_m_no represents the number of searches for the modulation frequency, n128 represents 128 10 cycles, F_b represents the fundamental wave frequency, and F_m represents the preset modulation frequency; fundamental wave signal S_b = V_b × sin (2 × pi × F_b × t128cyc), where V_b represents the fundamental wave amplitude, F _b represents the fundamental frequency, t128cyc represents the time value of each sampling value contained in 128 10-cycle waves; the modulation signal is expressed as S_m=1.0+A_m×sin(2×pi×F_m×t128cyc), wherein A_m represents the modulation amplitude, F_m represents the current modulation frequency, and t128cyc represents the time value of each sampling value contained in 128 10-cycle waves. The fundamental modulation signal can be expressed as S_bm=S_b.×S_m.

[0060] S440. Determine a 10-cycle effective value sequence corresponding to all sampling values ​​in each 10-cycle measurement period based on the fundamental wave modulation signal, perform Fourier transform FFT analysis on the 10-cycle effective value sequence to obtain a corresponding first spectrum array, and select a frequency point with the largest power spectrum density from the first spectrum array to perform energy enhancement to obtain a first enhancement value.

[0061] The first enhancement value may be referred to as enhancement value Q1, which may be obtained by dividing a frequency point amplitude by the sum of the amplitudes of two adjacent frequency points on the left and right.

[0062] In this embodiment, the 10-cycle effective value sequence corresponding to all the sampling values ​​in each 10-cycle measurement cycle is determined by the fundamental wave modulation signal. It can be understood that the basic measurement cycle is 10 cycles. Within the duration of 10 power grid cycles, the voltage signal is uniformly sampled. The 10-cycle effective value sequence is calculated by all the sampling values ​​in each 10-cycle measurement cycle. The 10-cycle effective value sequence is subjected to FFT analysis, and the time domain signal is converted to the frequency domain to obtain the corresponding first spectrum array. The frequency point with the largest power spectrum density is selected from the first spectrum array for energy enhancement to obtain the first enhancement value, and the current modulation frequency corresponding to the first enhancement value is recorded. Exemplarily, 256 times per cycle are sampled, and a total of 2560 values ​​are sampled. From these 2560 sampled values, the 10-cycle effective value sequence, harmonic value, and interharmonic value can be inferred, and the start sampling time and sequence number can be recorded; the specific calculation method of the 10-cycle effective value sequence, harmonic value, and interharmonic value can be achieved by squaring each value, averaging these square values, and then taking the square root of the mean. In this embodiment, the effective value of 10 cycles can be the root mean square, but the harmonic value and interharmonic value are calculated using FFT; the effective value, harmonic value, and interharmonic value of 150 cycles can all be calculated using the root mean square method.

[0063] In one embodiment, the energy enhancement method includes: determining a first amplitude and a second amplitude respectively corresponding to two frequency points adjacent to the frequency point with the largest power spectrum density; calculating the cumulative sum of the first amplitude and the second amplitude; and taking the ratio of the amplitude of the frequency point with the largest power spectrum density to the cumulative sum as the enhancement value, that is, dividing the amplitude of one frequency point by the sum of the amplitudes of the two adjacent frequency points on the left and right.

[0064] S450. Modify the first 10-cycle effective value in the 10-cycle effective value sequence to obtain an abnormal 10-cycle effective value sequence, perform FFT analysis on the abnormal 10-cycle effective value sequence to obtain a corresponding second spectrum array, and select the frequency point with the largest power spectrum density from the second spectrum array to perform energy enhancement to obtain a second enhancement value.

[0065] The second enhancement value may be referred to as enhancement value Q2, which may also be obtained by dividing a frequency point amplitude by the sum of the amplitudes of two adjacent frequency points on the left and right.

[0066] In this embodiment, the abnormal 10-cycle effective value sequence can be obtained by simulating the sampling gap, which can be understood as being obtained by intentionally omitting or modifying a sampling value in the 10-cycle sampling value sequence. In this embodiment, the abnormal 10-cycle effective value sequence is calculated by modifying or intentionally omitting the first sampling value in the 10-cycle sampling value sequence, and the abnormal 10-cycle effective value sequence is subjected to FFT analysis to obtain the corresponding second spectrum array, and the frequency point with the largest power spectrum density is selected from the second spectrum array for energy enhancement to obtain the second enhancement value.

[0067] S460: Determine a ratio of the first enhancement value to the second enhancement value, and use the ratio as a candidate enhancement value and store it in a candidate enhancement value list.

[0068] In this embodiment, the ratio of the first enhancement value to the second enhancement value is calculated, and the ratio is used as a candidate enhancement value and stored in a candidate enhancement value list, that is, the candidate enhancement value Q=Q1 / Q2 is taken, and the candidate enhancement value Q is recorded. Since there are multiple cyclic iterations, the candidate enhancement value list includes the candidate enhancement values ​​obtained in each round of iteration, so that the largest candidate enhancement value can be selected from multiple candidate enhancement values ​​later.

[0069] S470. Select the next modulation frequency from the preset modulation frequencies, and use the next modulation frequency as the current modulation frequency, return to the step of determining the modulation signal corresponding to the current modulation frequency to calculate the next candidate enhancement value, until all preset modulation frequencies are traversed, and a candidate enhancement value list including at least two candidate enhancement values ​​is obtained, and the maximum candidate enhancement value is selected from the candidate enhancement value list, and the modulation frequency corresponding to the maximum candidate enhancement value is used as the optimal modulation frequency.

[0070] Among them, the next modulation frequency may include the first next modulation frequency, the second next modulation frequency, the third next modulation frequency, and so on corresponding to the current modulation frequency, until all the preset modulation frequencies are traversed.

[0071] In this embodiment, the next modulation frequency is selected from the preset modulation frequency, and the next modulation frequency is used as the current modulation frequency, and the step of determining the modulation signal corresponding to the current modulation frequency is returned to calculate the next candidate enhancement value, until all preset modulation frequencies are traversed, and a candidate enhancement value list including at least two candidate enhancement values ​​is obtained, and the maximum candidate enhancement value is selected from the candidate enhancement value list, and the modulation frequency corresponding to the maximum candidate enhancement value is used as the optimal modulation frequency. It can be understood that the maximum candidate enhancement value Q is selected from the candidate enhancement value list, and the modulation frequency corresponding to the maximum Q value is used as the optimal modulation frequency. In this embodiment, the optimal modulation frequency is the frequency with the highest sensitivity, which can be very sensitive to abnormal changes in the cyc10 value. It should be noted that the method of selecting the maximum candidate enhancement value from the candidate enhancement value list can include: sorting all candidate enhancement values ​​contained in the candidate enhancement value list according to the size of the candidate enhancement value to obtain a sorting result, and selecting the candidate enhancement value with the largest sorting from the sorting result as the maximum candidate enhancement value. It can be understood that each candidate enhancement value is sorted in order from large to small or from small to large to obtain the largest candidate enhancement value.

[0072] Exemplarily, in order to better understand the calculation process of the optimal modulation frequency, Figure 5A flowchart for determining an optimal modulation frequency is provided for an embodiment of the present invention. In this embodiment, 128 10-cycles, 256 samples per cycle, and a modulation amplitude A_m of 20%, and a step frequency F_n = 1.0 / (n128×(10×1.0 / F_b)) are used as an example for explanation. The step frequency Fn is the reciprocal of the duration of the FFT input data, that is, the resolution of the spectrum generated by the FFT. In order to better understand the 62 Q values ​​of the 128 cyc10 value sequence when the fundamental wave is modulated with the optimal modulation frequency, Figure 6 A Q value of a voltage effective value sequence provided by an embodiment of the present invention. Since 128 is an integer power of 2, it is convenient for FFT calculation, the duration is about 25.6 seconds, and the spectrum resolution is about (1 / 25.6) Hz.

[0073] like Figure 5 As shown, the specific process is as follows:

[0074] a1. Preset the number of sampling points per cycle NumPerCyc=256, fundamental wave amplitude V_b, fundamental wave frequency F_b, duration of 128×10 cycles, modulation amplitude A_m=20%, step frequency Fn=1.0 / (128×10×1.0 / F_b).

[0075] a2. Set the modulation frequency F_m=Fn.

[0076] a3. Construct a sampling value sequence S_bm, calculate the cyc10 value sequence S_cyc10_bm from S_bm, and perform FFT analysis on the cyc10 value sequence S_cyc10_bm to obtain a spectrum array.

[0077] a4. Perform energy enhancement calculation on the 2nd to 62nd frequency points in the spectrum array, and record the maximum value among the 61 as Q1.

[0078] a5. Modify the first value of S_cyc10_bm, where the modified value is calculated by selecting the first 10-cycle sampling value sequence of S_bm, removing the first sampling value, and using the remaining sampling values ​​to calculate the modified value.

[0079] a6. Perform FFT analysis on the modified S_cyc10_bm to obtain a spectrum array, perform energy enhancement calculation on the 2nd to 62nd frequency points, and record the maximum value among the 61 as Q2.

[0080] a7. Record Q_div=Q1 / Q2.

[0081] a8. Increase Fn to F_m and determine whether F_m is greater than Fn×62. If so, execute a9; if not, return to execute a3.

[0082] a9. Pick out the largest Q_div from the 62 values ​​and use the F_m corresponding to the value as the optimal modulation frequency.

[0083] S480. Use the optimal modulation frequency to construct a fundamental wave modulation signal, a harmonic modulation signal, and an interharmonic modulation signal.

[0084] In this embodiment, the optimal modulation frequency is used to construct the fundamental modulation signal, the harmonic modulation signal and the interharmonic modulation signal. Exemplarily, the fundamental signal is S_b=V_b×sin(2×pi×F_b×t0_660); wherein t0_660 is represented as a sampling time point sequence, S_m=1.0+A_m×sin(2×pi×F_m×t0_660); the fundamental modulation signal is represented as S_bm=S_b.×S_m; the harmonic modulation signal is represented as S_hm=S_b+V_h×sin(2×pi×F_h×t0_660).×S_m; the interharmonic modulation signal is represented as S_im=S_b+V_i×sin(2×pi×F_i×t0_660).×S_m.

[0085] S490, counting the number of 10-cycle values, the number of 150-cycle values, the number of 10-cycle value sequences corresponding to each 10-cycle value, and the number of 150-cycle value sequences corresponding to each 150-cycle value within a preset time interval.

[0086] The preset time interval may be understood as each 10-minute time interval output by the power source, which is used to identify each full 10-minute moment, such as 0:10, 0:20, 1:30, and the like.

[0087] In this embodiment, the number of 10 cycles and the number of 150 cycles included in every 10 minutes are counted, as well as the number of 10-cycle effective values, 10-cycle harmonic values ​​and 10-cycle inter-harmonic values ​​corresponding to each 10 cycles, and the number of 150-cycle effective values, 150-cycle harmonic values ​​and 150-cycle inter-harmonic values ​​corresponding to each 150 cycles.

[0088] S4100, obtaining a 10-cycle effective value sequence through a fundamental wave modulation signal and the number of sampling values ​​per cycle within a preset time interval, and aggregating the 10-cycle effective value sequence into a 150-cycle effective value sequence to obtain at least one 150-cycle effective value sequence.

[0089] The 10-cycle effective value sequence includes effective values ​​and time scales corresponding to the effective values, and the 150-cycle effective value sequence includes effective values ​​and time scales corresponding to the effective values.

[0090] In this embodiment, the fundamental wave modulation signal and the number of 10-cycle values ​​included in every 10 minutes are used to combine the 10-cycle effective values ​​corresponding to the multiple 10 cycles included in 10 minutes into a 10-cycle effective value sequence Cyc10_bm within 10 minutes, and the 150-cycle effective value sequence Sec3_bm corresponding to the multiple 150 cycles is obtained through the 10-cycle effective value sequence and the number of 150-cycle values ​​included in every 10 minutes.

[0091] S4110. Obtain a 10-cycle harmonic value sequence through the harmonic modulation signal and the number of harmonic values ​​corresponding to each cycle within a preset time interval, and aggregate every 15 10-cycle harmonic value sequences into a 150-cycle harmonic value sequence to obtain at least one 150-cycle harmonic value sequence.

[0092] The 10-cycle harmonic value sequence includes harmonic values ​​and time scales corresponding to the harmonic values, and the 150-cycle harmonic value sequence includes harmonic values ​​and time scales corresponding to the harmonic values.

[0093] In this embodiment, the harmonic modulation signal and the number of 10-cycle values ​​included in every 10 minutes are used to form a 10-cycle harmonic value sequence Cyc10_hm within 10 minutes by combining the 10-cycle harmonic values ​​corresponding to the multiple 10 cycles included in 10 minutes, and a 150-cycle harmonic value sequence Sec3_hm corresponding to multiple 150 cycles is obtained through the 10-cycle harmonic value sequence and the number of 150-cycle values ​​included in every 10 minutes.

[0094] S4120, obtaining a 10-cycle interharmonic value sequence through the interharmonic modulation signal and the number of interharmonic values ​​per cycle within a preset time interval, and aggregating the 10-cycle interharmonic value sequence into a 150-cycle interharmonic value sequence to obtain at least one 150-cycle interharmonic value sequence.

[0095] The 10-cycle interharmonic value sequence includes interharmonic values ​​and time scales corresponding to the interharmonic values, and the 150-cycle interharmonic value sequence includes interharmonic values ​​and time scales corresponding to the interharmonic values.

[0096] In this embodiment, the interharmonic modulation signal and the number of 10-cycle values ​​included in every 10 minutes are used to form an interharmonic value sequence Cyc10_im with the 10-cycle interharmonic values ​​corresponding to the multiple 10 cycles included in 10 minutes, and the interharmonic value sequence S_sec3_im is obtained by forming an interharmonic value sequence with the 10-cycle interharmonic values ​​corresponding to the multiple 10 cycles included in 10 minutes and the number of 150 cycles included in every 10 minutes.

[0097] S4130, performing FFT analysis on the 10-cycle harmonic value sequence to obtain a third spectrum array, calculating third enhancement values ​​corresponding to each frequency point in the third spectrum array, and selecting the largest enhancement value from the third enhancement values ​​as the enhancement value of the 10-cycle harmonic value sequence.

[0098] In this embodiment, FFT analysis is performed on a 10-cycle harmonic value sequence to obtain a third spectrum array, and third enhancement values ​​corresponding to each frequency point in the third spectrum array are calculated. The largest enhancement value is selected from the third enhancement values ​​as the enhancement value of the 10-cycle harmonic value sequence. Specifically, 128×10 cycles are taken, with 256 samples per cycle and 2560 sampling values ​​for 10 cycles. One harmonic value is calculated for every 10 cycle sampling values, for a total of 128 harmonic values. The 128 harmonic values ​​are input into the function Q_rms_max to obtain the Q value of the harmonic value sequence. In this embodiment, the function Q_rms_max is to perform FFT analysis on the 10-cycle harmonic value sequence to obtain a third spectrum array, calculate the third enhancement values ​​corresponding to each frequency point in the third spectrum array, and select the largest enhancement value from the third enhancement values ​​as the enhancement value of the 10-cycle harmonic value sequence. Specifically, determine the amplitude corresponding to the frequency point with the largest power spectral density in the third spectrum array, and determine the amplitudes corresponding to the two frequency points adjacent to the frequency point with the largest power spectral density in the third spectrum array, calculate the cumulative sum of the amplitudes corresponding to the two frequency points, and take the ratio of the amplitude of the frequency point with the largest power spectral density to the cumulative sum as the corresponding enhancement value.

[0099] In one embodiment, the code of the function Q_rms_max can be expressed as: function[out_Q_max, out_Q_max_no] = Q_rms_max(rms_n); % Analyze and calculate the maximum Q value (i.e., the enhancement value) of a group of numbers, the input rms_n can be a group of effective values ​​or a group of harmonic amplitudes; the output out_Q_max is a value;

[0100] fft_rms_n=fft(rms_n); %Perform FFT analysis on this set of numbers;

[0101] bin_fft_rms_n=BIN_fft(fft_rms_n); % Calculate the effective value or amplitude of each frequency point;

[0102] Q_rms_n=Q_bin_fft(bin_fft_rms_n); % Calculate the Q value of each frequency point;

[0103] [out_Q_max, out_Q_max_no] = max(Q_rms_n); % Find the maximum Q value.

[0104] In this embodiment, max is a system function of the MATLAB language, which is used to find the maximum value in an array; fft is a system function, which is used to calculate the frequency spectrum of an array.

[0105] In one embodiment, the calculation method of the third enhancement value includes: determining the amplitudes corresponding to two frequency points adjacent to the frequency point with the largest power spectrum density; calculating the cumulative sum of the amplitudes corresponding to the two frequency points; taking the ratio of the amplitude of the frequency point with the largest power spectrum density to the cumulative sum as the enhancement value, and selecting the largest enhancement value from multiple third enhancement values ​​as the enhancement value of the 10-cycle harmonic value sequence.

[0106] S4140, performing FFT analysis on the 10-cycle interharmonic value sequence to obtain a corresponding fourth spectrum array, calculating fourth enhancement values ​​corresponding to each frequency point in the fourth spectrum array, and selecting the largest enhancement value from the fourth enhancement values ​​as the enhancement value of the 10-cycle interharmonic value sequence.

[0107] In this embodiment, a Fourier transform FFT analysis is performed on a 10-cycle interharmonic value sequence to obtain a corresponding fourth spectrum array, and fourth enhancement values ​​corresponding to each frequency point in the fourth spectrum array are calculated. The maximum enhancement value is selected from the fourth enhancement values ​​as the enhancement value of the 10-cycle interharmonic value sequence. Specifically, 128×10 cycles are taken, 256 samples are collected per cycle, and 2560 sampling values ​​are collected for 10 cycles. One interharmonic value is calculated for every 10 cycle sampling values, for a total of 128 interharmonic values. The 128 interharmonic values ​​are input into the function Q_rms_max to obtain the Q value of the interharmonic value sequence. In this embodiment, the function Q_ rms_max is the fourth spectrum array obtained by performing FFT analysis on the 10-cycle interharmonic value sequence, calculating the fourth enhancement value corresponding to each frequency point in the fourth spectrum array, selecting the largest enhancement value from the fourth enhancement value as the enhancement value of the 10-cycle interharmonic value sequence, specifically, determining the amplitude corresponding to the frequency point with the largest power spectrum density in the fourth spectrum array, and determining the amplitudes corresponding to the two frequency points adjacent to the frequency point with the largest power spectrum density in the fourth spectrum array, calculating the cumulative sum of the amplitudes corresponding to the two frequency points, and taking the ratio of the amplitude of the frequency point with the largest power spectrum density to the cumulative sum as the corresponding enhancement value.

[0108] S4150. Divide the numbers of 150-cycle effective value sequences, 150-cycle harmonic value sequences, and 150-cycle interharmonic value sequences within a preset time interval into a preset number of continuous value sequences, and perform FFT analysis on each continuous value sequence to obtain the corresponding fifth spectrum arrays, calculate the fifth enhancement value corresponding to each frequency point in each fifth spectrum array, and select the largest enhancement value from each fifth enhancement value as the enhancement value corresponding to the 150-cycle effective value sequence, the 150-cycle harmonic value sequence, and the 150-cycle interharmonic value sequence.

[0109] In this embodiment, the numbers corresponding to the 150-cycle effective value sequence, the 150-cycle harmonic value sequence, and the 150-cycle interharmonic value sequence within the preset time interval are divided into a preset continuous number of continuous value sequences in turn, and Fourier transform FFT analysis is performed on each continuous value sequence to obtain the corresponding fifth spectrum arrays, and the fifth enhancement values ​​corresponding to each frequency point in each fifth spectrum array are calculated, and the largest enhancement value is selected from each fifth enhancement value as the enhancement value corresponding to the 150-cycle effective value sequence, the 150-cycle harmonic value sequence, and the 150-cycle interharmonic value sequence. Specifically, the amplitude corresponding to the frequency point with the largest power spectrum density in the fifth spectrum array is determined, and the amplitudes corresponding to the two frequency points adjacent to the frequency point with the largest power spectrum density in the fifth spectrum array are determined, the cumulative sum of the amplitudes corresponding to the two frequency points is calculated, and the ratio of the amplitude of the frequency point with the largest power spectrum density to the cumulative sum is used as the corresponding enhancement value. Exemplarily, when the fundamental frequency F_b=50Hz, the duration of 10 cycles is 0.2 seconds and the duration of sec3 is 3 seconds, so the number of 150-cycle value sequences within the preset time interval can be divided into at least two 3-second value sequences, and the 3-second value sequence is subjected to FFT analysis to obtain the corresponding fifth spectrum array, and the fifth enhancement value corresponding to each frequency point in the fifth spectrum array is calculated, and the largest enhancement value is selected from the fifth enhancement value as the Q value of the 150-cycle value sequence; wherein, the Q value of the 150-cycle value sequence includes: the Q value of the 150-cycle effective value sequence, the Q value of the 150-cycle harmonic value sequence, and the Q value of the 150-cycle interharmonic value sequence. The Q value in this embodiment is the enhancement value.

[0110] In one embodiment, a method for verifying whether a sampling value gap can be detected includes: simulating a sampling value overlap to obtain an abnormal sampling sequence, and performing FFT analysis on the abnormal sampling sequence to obtain a corresponding spectrum array, selecting a frequency point with the largest power spectrum density from the spectrum array for energy enhancement to obtain an enhancement value, using the enhancement value as the Q value of the abnormal sampling sequence, and determining the ratios of the third enhancement value, the fourth enhancement value, and the fifth enhancement value to the Q value of the abnormal sampling sequence; when the ratio is greater than a preset threshold, it is determined that the sampling value overlap can be detected.

[0111] S4160, calculating the number of 10-cycle value sequences from the first preset time to the second preset time, recording the number of 10-cycle value sequences as N, and taking the Nth 10-cycle value of the 10-cycle value sequence as the 10-cycle overlap value.

[0112] The Nth value refers to the last 10-cycle value of the 10-cycle value sequence belonging to the first preset time.

[0113] Exemplarily, the first preset time is 0:10, and the second preset time is 0:20.

[0114] In this embodiment, the number of 10-cycle value sequences from the first preset time to the second preset time is calculated, the number of the 10-cycle value sequences is recorded as Num_cyc10_10min, and the Num_cyc10_10min value of the 10-cycle value sequence is used as the 10-cycle overlap value. Specifically, F_m is used to generate a fundamental modulation signal S_bm with a duration of 660 seconds so that the 10 cycles spanning the second preset time are complete, wherein the 10 cycles spanning the second preset time are the first 10 cycles starting from the second preset time, Cyc10_bm is generated from S_bm, and the Num_Cyc10_10min value of Cyc10_bm is Cyc10_bmZ, because the sampling value sequence before and after 10 minutes is continuous and equally spaced, the time of the first sampling value used to calculate the value is before 10 minutes, and the time of the last sampling value used to calculate the value is after 10 minutes. The fundamental modulation signal S_bm is constructed by the modulation signal and the fundamental signal, and generating Cyc10_bm from S_bm is to calculate the cyc10 value sequence from S_bm, and perform FFT analysis on the cyc10 value sequence to obtain a spectrum array. In this embodiment, the generation methods of Cyc10_mZ and Cyc10_imZ are similar.

[0115] S4170, starting from the first 10-cycle values ​​of the 10-cycle value sequence within the first preset time to the second preset time, divide the preset number of 10-cycle values ​​into a group for calculating 150-cycle values, and when the number of 10-cycle values ​​in the last group is less than the preset number, record the number of 10-cycle values ​​in the last group as the first number of 10-cycle values, and select the second number of 10-cycle values ​​from the 10-cycle value sequence starting from the second preset time, and aggregate the first number of 10-cycle values ​​and the second number of 10-cycle values ​​into a 150-cycle overlapping value in sequence.

[0116] In this embodiment, the preset number is a plurality of 10-cycle values ​​that will form a group of 150-cycle values. The preset number can be customized according to the needs. For example, in order to better obtain the 150-cycle overlapping value, every 15 10-cycle values ​​can be divided into a group of 150-cycle values. In this embodiment, starting from the first value of the 10-cycle value sequence within the first preset time to the second preset time, every 15 values ​​are divided into a group for calculating the 150-cycle value. When the number of the last group is less than 15, the remaining 10-cycle values ​​are selected from the 10-cycle value sequence starting from the second preset time, and the 150-cycle overlapping value is aggregated from this last group of 10-cycle values. Exemplarily, the first part is selected from the last cyc10 value of the present 10 minutes, the number is Num_cyc10_10min-floor(Num_cyc10_10min / 15), the second part is selected from the cyc10 value at the beginning of the next 10 minutes, the number is ceil(Num_cyc10_10min / 15)-Num_cyc10_10min, these two parts have a total of 15 cyc10 values, which are combined into a sequence in order, and Sec3_bmZ is aggregated from these 15 values. The generation process of Sec3_hmZ and Sec3_imZ is similar. In this embodiment, ceil is a system function of MATLAB, which is used to round up, and floor is used to round down.

[0117] S4180. Select a third number of 10-cycle values ​​from the 10-cycle value sequence from the first preset time to the second preset time, and select a fourth number of 10-cycle values ​​from the 10-cycle value sequence starting from the second preset time, and sequentially combine the third number of 10-cycle values ​​and the fourth number of 10-cycle values ​​into a target 10-cycle value sequence, perform FFT analysis on the target 10-cycle value sequence to obtain the corresponding sixth frequency spectrum array, calculate the sixth enhancement value corresponding to each frequency point in the sixth frequency spectrum array, and select the largest enhancement value from the sixth enhancement value as the enhancement value of the 10-cycle overlapping value.

[0118] The target 10-cycle value sequence may be understood as a new 10-cycle value sequence obtained by combining the third number of 10-cycle values ​​and the fourth number of 10-cycle values.

[0119] In this embodiment, a third number of 10-cycle values ​​are selected from a 10-cycle value sequence from a first preset time to a second preset time, and a fourth number of 10-cycle values ​​are selected from a 10-cycle value sequence starting from the second preset time, and the third number of 10-cycle values ​​and the fourth number of 10-cycle values ​​are sequentially combined into a target 10-cycle value sequence, and an FFT analysis is performed on the target 10-cycle value sequence to obtain a corresponding sixth spectrum array, and sixth enhancement values ​​corresponding to each frequency point in the sixth spectrum array are calculated, and a maximum enhancement value is selected from the sixth enhancement values ​​as the enhancement value of the 10-cycle overlapping value. Specifically, the amplitude corresponding to the frequency point with the largest power spectrum density in the sixth spectrum array is determined, and the amplitudes corresponding to two frequency points adjacent to the frequency point with the largest power spectrum density in the sixth spectrum array are determined, and the cumulative sum of the amplitudes corresponding to the two frequency points is calculated, and the ratio of the amplitude of the frequency point with the largest power spectrum density to the cumulative sum is used as the corresponding enhancement value. Exemplarily, for a sequence containing 128 Cyc10 values, the last 127 values ​​are selected from the Cyc10 values ​​of the current 10 minutes (i.e., the first 127 values ​​are the last values ​​at 0:10), and the first value is selected from the Cyc10 values ​​of the next 10 minutes (the last Cyc10 value is the first value at 0:20), and the values ​​are combined in order to form a sequence of 128 values. This sequence is input to the function Q_rms_max, and the calculated value is Q_Cyc10_bmZ. The calculation process of Q_Cyc10_hmZ and Q_Cyc10_imZ is similar. In this embodiment, the function Q_rms_max is a process of performing FFT analysis on the sequence to calculate the amplitude of each frequency point and the Q value of each frequency point, thereby finding the maximum Q value.

[0120] S4190. Aggregate every 15 10-cycle values ​​from the first preset time to the second preset time to obtain the corresponding 150-cycle value, form a target 150-cycle value sequence from the 150-cycle values, perform FFT analysis on the target 150-cycle value sequence to obtain the corresponding seventh spectrum array, calculate the seventh enhancement value corresponding to each frequency point in the seventh spectrum array, and select the largest enhancement value from the seventh enhancement value as the enhancement value of the 150-cycle overlapping value.

[0121] In this embodiment, every 15 10-cycle values ​​are aggregated to obtain a target 150-cycle value sequence, and the target 150-cycle value sequence is subjected to FFT analysis to obtain the corresponding seventh spectrum array, and the seventh enhancement value corresponding to each frequency point in the seventh spectrum array is calculated, and the largest enhancement value is selected from the seventh enhancement value as the enhancement value of the 150-cycle overlap value. Specifically, the amplitude corresponding to the frequency point with the largest power spectrum density in the seventh spectrum array is determined, and the amplitudes corresponding to the two frequency points adjacent to the frequency point with the largest power spectrum density in the seventh spectrum array are determined, and the cumulative sum of the amplitudes corresponding to the two frequency points is calculated, and the ratio of the amplitude of the frequency point with the largest power spectrum density to the cumulative sum is used as the corresponding enhancement value. It can be understood that the calculation method of Q_Sec3_bmZ is to select the last Num_Sec3_Q values ​​from the 150-cycle value of the present 10 minutes, and input them into the function Q_rms_max to calculate Q_Sec3_bmZ, and the calculation process of Q_Sec3_hmZ and Q_Sec3_imZ is similar.

[0122] S4200, compare the number of 10-cycle value sequences and the number of 150-cycle value sequences in the standard characteristic value sequence with the actual number of 10-cycle value sequences and the actual number of 150-cycle value sequences, respectively. When the comparison is equal, determine that the preliminary verification result has passed.

[0123] In this embodiment, the number of 10-cycle value sequences and the number of 150-cycle value sequences in the standard characteristic value sequence are compared with the actual number of 10-cycle value sequences and the actual number of 150-cycle value sequences, respectively. When the comparison is equal, it is determined that the preliminary verification result passes. For example, the time stamp of the measurement data collected from the EUT is counted, and the number of Cyc10 values ​​and the number of Sec3 values ​​between 0:10 and 0:20 are counted. It is determined whether the number of Cyc10 values ​​is equal to Num_Cyc10_10min and the number of Sec3 values ​​is equal to Num_Sec3_10min. If they are not equal, such abnormality is reported and the verification is stopped.

[0124] S4210. Determine the error between the 10-cycle value sequence in the standard eigenvalue sequence and the actual 10-cycle value sequence in the actual eigenvalue sequence, as well as the error between the 150-cycle value sequence in the standard eigenvalue sequence and the actual 150-cycle value sequence in the actual eigenvalue sequence. If the error does not exceed the preset error threshold, determine that the preliminary inspection result has passed.

[0125] In this embodiment, the error between the 10-cycle value sequence in the standard characteristic value sequence and the actual 10-cycle value sequence in the actual characteristic value sequence, as well as the error between the 150-cycle value sequence in the standard characteristic value sequence and the actual 150-cycle value sequence in the actual characteristic value sequence are calculated. When the error does not exceed the preset error threshold, the preliminary verification result is determined to be passed. For example, the relative error between each Cyc10 value collected from 0:10 to 0:20 and the 10-cycle value sequence included in the standard characteristic value sequence is calculated. The absolute value of the error value should not be greater than (0.5%×60%), in order to ensure that the error does not exceed 0.5% when the equipment is used in batches. During verification, it is limited to 60% of the agreed value, and the number of comparisons is Num_Cyc10_10min. If the standard is exceeded, the sequence number of the error value is reported and the verification is stopped. And calculate the relative error between each Sec3 value collected from 0:10 to 0:20 and the 150-cycle value sequence contained in the standard characteristic value sequence. The absolute value of the error value should not be greater than (0.5% × 60%). The number of comparisons is Num_Sec3_10min. If it exceeds the standard, the number of the error value is reported and the test is stopped.

[0126] S4220. Determine the target calibration result of the actual calibration signal measurement result output by the power quality monitoring equipment in the distribution station area based on the preliminary calibration result.

[0127] In this embodiment, after all basic tests are passed, the calculation of Cyc10 values ​​is then tested to see if there are any missing or overlapping sampling values. The basic principle is to perform Q value analysis and comparison on the Cyc10 value sequence starting from 0:10 collected from the EUT, and to perform Q value analysis and comparison on the Sec3 value sequence starting from 0:10 collected from the EUT.

[0128] In one embodiment, a target calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in a distribution station area is determined based on a preliminary calibration result, including: a first calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in a distribution station area is determined based on an enhanced value of a 10-cycle value sequence in a standard characteristic value sequence and an enhanced value of an actual 10-cycle value sequence in an actual characteristic value sequence; a second calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in a distribution station area is determined based on an enhanced value of a 150-cycle value sequence in a standard characteristic value sequence and an enhanced value of an actual 150-cycle value sequence in an actual characteristic value sequence; a third calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in a distribution station area is determined based on an enhanced value of a 10-cycle overlap value in a standard characteristic value sequence and an enhanced value of an actual 10-cycle overlap value in an actual characteristic value sequence; and a fourth calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in a distribution station area is determined based on an enhanced value of a 150-cycle overlap value in a standard characteristic value sequence, an enhanced value of an actual 150-cycle overlap value in an actual characteristic value sequence, and a preset correction factor.

[0129] In one embodiment, a first verification result of an actual verification signal measurement result output by a power quality monitoring device in a distribution station area is determined based on an enhanced value of a 10-cycle value sequence in a standard characteristic value sequence and an enhanced value of an actual 10-cycle value sequence in an actual characteristic value sequence, including: counting the total number of 10 cycles within a first preset time; wherein each 10 cycles corresponds to a corresponding actual characteristic value sequence and a standard characteristic value sequence, and starting from the first 10 cycles within the first preset time, judging whether the error between the enhanced value of the actual 10-cycle value sequence corresponding to the first 10 cycles to the last 10 cycles and the enhanced value of the 10-cycle value sequence in the standard characteristic value sequence is within a preset error threshold range, that is, comparing the enhanced value of the actual 10-cycle effective value sequence, the enhanced value of the actual 10-cycle harmonic value sequence, and the enhanced value of the actual 10-cycle interharmonic value sequence in the enhanced value of the actual 10-cycle value sequence with the enhanced value of the standard 10-cycle value sequence, respectively, according to the corresponding time scales. The enhanced value of the 10-cycle effective value sequence, the enhanced value of the 10-cycle harmonic value sequence, and the enhanced value of the 10-cycle interharmonic value sequence are compared; if they are within the preset error threshold range, it is determined that the test is normal, and the time scale of the 10-cycle value sequence corresponding to the last 10 cycles is greater than or equal to the second preset time. If it is greater than or equal to the second preset time, it is determined that the 10-cycle value sequence corresponding to each 10 cycles within the first preset time is qualified. If it is less than the second preset time, the second 10 cycles are selected from the first preset time, and the second 10 cycles are used as the first 10 cycles, and the judgment step of whether the error is within the preset error threshold range is returned; if it is not within the preset error threshold range, it is determined that the actual 10-cycle value sequence corresponding to the first 10 cycles to the last 10 cycles has a test abnormality, and the test result is determined according to the preset first correction factor and the 10-cycle value sequence in the standard characteristic value sequence with the same time scale as the actual 10-cycle value sequence. Among them, the preset first correction factor can be set as required.

[0130] In some embodiments, the verification result is determined based on a preset first correction factor and a 10-cycle value sequence in a standard characteristic value sequence with the same time scale as the actual 10-cycle value sequence, including: setting an abnormal sequence number for each 10-cycle with verification abnormality, and selecting an abnormal sequence number as the current abnormal sequence number, using the 10-cycle value sequence in the standard characteristic value sequence with the same time scale from the first preset time to the second preset time, and the preset first correction factor to correct the actual 10-cycle value sequence corresponding to the 10-cycle with the current abnormal sequence number, and re-verifying the actual 10-cycle value sequence corresponding to the 10-cycle with the corrected current abnormal sequence number, and selecting the next abnormal sequence number from the abnormal sequence number, taking the next abnormal sequence number as the current abnormal sequence number, and returning to the step of correcting the actual 10-cycle value sequence corresponding to the 10-cycle with the current abnormal sequence number, until the verification of the 10-cycle with all abnormal sequence numbers is completed, and at least two actual 10-cycle value sequences with verification abnormalities are obtained.

[0131] In one embodiment, the actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number after correction is re-calibrated, including: calculating the enhancement value of the actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number after correction as the current enhancement value; judging whether the error between the current enhancement value and the enhancement value of the 10-cycle value sequence with the same time scale in the standard characteristic value sequence is within a preset error threshold range; if so, determining that the actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number before correction is abnormal; if not, restoring the actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number after correction.

[0132] In this embodiment, a method of specifically using a 10-cycle value sequence in a standard characteristic value sequence with the same time scale from a first preset time to a second preset time, and a preset correction factor to correct an actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number includes: finding out a 10-cycle value sequence in a standard characteristic value sequence with the same time scale, and then multiplying the 10-cycle value sequence in the standard characteristic value sequence with the same time scale by the preset correction factor to obtain a product, and replacing the actual 10-cycle value sequence with the product; illustratively, the standard Cyc10_bm value with the same number between 0:10 and 0:20 is multiplied by (V_b / Sec3_A) to replace the value of the EUT.

[0133] In the present embodiment, the manner of determining the third verification result of the actual verification signal output by the power quality monitoring equipment in the distribution station area according to the enhanced value of the 10-cycle overlap value in the standard characteristic value sequence and the enhanced value of the actual 10-cycle overlap value in the actual characteristic value sequence is the same as the manner of determining the above-mentioned first verification result, and this embodiment will not be described in detail here. Similarly, the manner of determining the fourth verification result of the actual verification signal output by the power quality monitoring equipment in the distribution station area according to the enhanced value of the 150-cycle overlap value in the standard characteristic value sequence, the enhanced value of the actual 150-cycle overlap value in the actual characteristic value sequence and the preset correction factor is the same as the manner of determining the second verification result, and this embodiment will not be described in detail here.

[0134] For better understanding of the Cyc10_bm detection method, Figure 7 A calibration flow chart for abnormal measurement of 10-cycle value provided in an embodiment of the present invention. The abnormality judgment criterion in this embodiment is to calculate the Q value of each sequence (128 values) to see whether it is less than 0.1 times the ideal value Q_Cyc10_bm. If it is less than 0.1 times, it is judged as abnormal and the calibration is stopped.

[0135] The principle of correcting the Cyc10 value is to replace the EUT value with the ideal Cyc10_bm value of the same number between 0:10 and 0:20 multiplied by (V_b / Sec3_A). The principle is to assume that the value of this number is abnormal and replace it with a normal value. For Cyc10_bm, the difference factor between the EUT measurement value and the PPS output value is (V_b / Sec3_A). The calibration process for Cyc10_hm abnormality is similar, and the correction factor is (V_b / Sec3_B). The calibration process for Cyc10_im abnormality is similar, and the correction factor is (V_b / Sec3_C); among them, V_b represents the fundamental amplitude; Sec3_A represents the corresponding identifier of Cyc10_bm; Sec3_B represents the corresponding identifier of Cyc10_hm, and Sec3_C represents the corresponding identifier of Cyc10_im. Figure 7 The specific verification process is as follows:

[0136] b1. Set sequence number no=1, len=127.

[0137] b2. Analyze whether the cyc10 values ​​from no to (no+len) are abnormal. If normal, execute b3; if abnormal, execute b6.

[0138] b3, no=no+1.

[0139] b4. Is the time stamp of number (no+len+1) greater than or equal to 0:20:00? If so, execute b5; if not, return to execute b2.

[0140] b5. The conclusion is that each CYC10 value in these 10 minutes is qualified.

[0141] b6. Set the sequence number nox=0.

[0142] b7. Correct the (no+nox)th cyc10 value.

[0143] b8. Analyze whether the Cyc10 values ​​from no to (no+len) are abnormal. If so, execute b9; if not, execute b12.

[0144] b9. Restore the (no+nox)th Cyc10 value.

[0145] b10. Determine whether nox=nox+1 and nox>len. If yes, execute b11. If no, return to execute b8.

[0146] b11. The conclusion is that multiple Cyc10 values ​​between no to (no+len) are abnormal.

[0147] b12. The conclusion is that the (no+nox)th Cyc10 value is abnormal.

[0148] It should be noted that this step is used to detect whether the sampled values ​​are correctly overlapped and used. This step is only performed if the final Cyc10 value of min10 has been verified to be qualified. Specifically, the Cyc10 valid value sequence collected from the EUT is used to calculate Q_Cyc10_bmZ according to its time stamp by the above steps. This value should not be greater than 1.5 times the ideal value and not less than 0.5 times the ideal value, otherwise an abnormality is reported. The method of verifying Q_Cyc10_hmZ and Q_Cyc10_imZ is similar.

[0149] In one embodiment, a second verification result of an actual verification signal output by a power quality monitoring device in a distribution station area is determined based on the enhanced value of a 150-cycle value sequence in a standard characteristic value sequence and the enhanced value of an actual 150-cycle value sequence in an actual characteristic value sequence, including: counting the total number of 150 cycles within a first preset time; wherein each 150 cycles corresponds to a corresponding actual characteristic value sequence and a standard characteristic value sequence; starting from the first 150 cycles within the first preset time, judging whether the error between the enhanced value of the actual 150-cycle value sequence corresponding to the first 150 cycles to the last 150 cycles and the enhanced value of the 150-cycle value sequence in the standard characteristic value sequence is within a preset error threshold range, that is, comparing the enhanced value of the actual 150-cycle effective value sequence, the enhanced value of the actual 150-cycle harmonic value sequence, and the enhanced value of the actual 150-cycle interharmonic value sequence in the enhanced value of the actual 150-cycle value sequence with the standard characteristic value sequence according to the corresponding time scales respectively. The enhanced values ​​of the 150-cycle effective value sequence, the enhanced values ​​of the 150-cycle harmonic value sequence, and the enhanced values ​​of the 150-cycle interharmonic value sequence in the enhanced values ​​of the 150-cycle value sequence are compared; if so, it is determined that the test is normal, and the time scale of the 150-cycle value sequence corresponding to the last 150 cycles is greater than or equal to the second preset time. If so, it is determined that the 150-cycle value sequence corresponding to each 150 cycle in the first preset time is qualified. If not, the second 150 cycles are selected from the first preset time, and the second 150 cycles are used as the first 150 cycles, and the judgment step of whether the error is within the preset error threshold range is returned; if not, it is determined that the actual 150-cycle value sequence corresponding to the first 150 cycles to the last 150 cycles has a test abnormality, and the test result is determined according to the preset second correction factor and the 150-cycle value sequence in the standard characteristic value sequence with the same time scale as the actual 150-cycle value sequence. Among them, the preset second correction factor can be set as required.

[0150] In one embodiment, the verification result is determined based on a preset second correction factor and a 150-cycle value sequence in a standard characteristic value sequence with the same time scale as the actual 150-cycle value sequence, including: setting an abnormal sequence number for each 150-cycle value sequence with a verification abnormality, and selecting an abnormal sequence number as the current abnormal sequence number, using the 150-cycle value sequence in the standard characteristic value sequence with the same time scale from the first preset time to the second preset time, and the preset second correction factor to correct the actual 10-cycle value sequence corresponding to the 150-cycle value sequence of the current abnormal sequence number, and re-verifying the actual 150-cycle value sequence corresponding to the 150-cycle value sequence of the corrected current abnormal sequence number, and selecting the next abnormal sequence number from the abnormal sequence number, taking the next abnormal sequence number as the current abnormal sequence number, and returning to the step of correcting the actual 150-cycle value sequence corresponding to the 150-cycle value sequence of the current abnormal sequence number, until the verification of the 150-cycle value sequences of all abnormal sequence numbers is completed, and at least two actual 150-cycle value sequences with verification abnormalities are obtained.

[0151] For example, to better understand the anomaly detection of sec3 value sequence Sec3_bm, Figure 8 A calibration flow chart for abnormal measurement of 150-cycle value is provided for an embodiment of the present invention. The abnormality judgment criterion in this embodiment is to calculate the Q value of each sequence (Num_Sec3_Q values) to see whether it is less than 0.1 times the ideal value Q_Sec_bm. If it is less than, it is judged as abnormal and the calibration is stopped.

[0152] The principle of correcting the sec3 value is to replace the EUT value with the ideal Sec3_bm value of the same number between 0:10 and 0:20 multiplied by (V_b / Sec3_A). The principle is to assume that the value of this number is abnormal and replace it with a normal value. For Sec3_bm, the difference factor between the EUT measured value and the PPS output value is (V_b / Sec3_A). The verification process for Sec3_hm abnormality is similar, and the correction factor is (V_b / Sec3_B). The verification process for Sec3_im abnormality is also similar, and the correction factor is (V_b / Sec3_C); among them, V_b represents the fundamental amplitude; Sec3_A represents the identifier corresponding to Sec3_bm; Sec3_B represents the identifier corresponding to Sec3_hm, and Sec3_C represents the identifier corresponding to Sec3_im.

[0153] like Figure 8 The specific verification process is as follows:

[0154] c1. Set sequence number no=1, len=Num_sec3_Q.

[0155] c2. Analyze whether the Sec3 value sequence from no to (no+len) is abnormal. If normal, execute c3; if abnormal, execute c6.

[0156] c3, no=no+1.

[0157] c4. Is the time stamp of number (no+len+1) greater than 0:20:00? If so, execute c5; if not, return to execute c2.

[0158] c5. The conclusion is that every Sec3 value within these 10 minutes is qualified.

[0159] c6. Set the sequence number nox=0.

[0160] c7. Correct the (no+nox)th Sec3 value.

[0161] c8. Analyze whether the Sec3 values ​​from no to (no+len) are abnormal. If so, execute c9; if not, execute c12.

[0162] c9. Restore the (no+nox)th Sec3 value.

[0163] c10. Determine whether nox=nox+1 and nox>len. If yes, execute c11. If no, return to execute c8.

[0164] c11. The conclusion is that multiple Sec3 values ​​between no to (no+len) are abnormal.

[0165] c12. The conclusion is that the (no+nox)th Sec3 value is abnormal.

[0166] It should be noted that this step is designed to detect whether the Cyc10 value is correctly overlapped. This step is performed only if the final Sec3 value of min10 has been verified to be qualified. Specifically, the Sec3 valid value sequence collected from the EUT is used to calculate Q_Sec3_bmZ according to its time scale according to the above steps. This value should not be greater than 1.5 times the ideal value and not less than 0.5 times the ideal value, otherwise an abnormality is reported. The method for verifying Q_Sec3_hmZ and Q_Sec3_imZ is similar.

[0167] The above technical scheme in this embodiment designs a calculation method of a characteristic value Q that identifies the uniqueness of a group of voltage effective values, a group of voltage harmonic values, and a group of voltage interharmonic values. When this group of effective values ​​changes slightly, the characteristic value Q can be caused to change. Three voltage signals are designed for verification through the optimal modulation frequency, including fundamental modulation signal, harmonic modulation signal, and interharmonic modulation signal. Multiple characteristic values ​​of these three modulation signals are calculated as standard characteristic value sequences. Based on this, the actual 10-cycle value sequence and 150-cycle value sequence collected from the verified equipment are used to calculate the error between the actual characteristic value sequence and the standard characteristic value sequence, and the characteristic value comparison is performed, so that multiple anomalies can be identified, the anomalies of the verification data can be judged from multiple dimensions, and the time point when the anomaly occurs can be accurately provided. The detected anomalies include but are not limited to the detection of omission or overlap of a single sampling value, the detection of omission or overlap of a single 10-cycle value, the detection of omission or overlap of 150-cycle value, and the detection of overlap at 10 minutes.

[0168] In one embodiment, Fig. 9 This is a structural block diagram of a calibration system for power quality monitoring equipment in a distribution station area provided by an embodiment of the present invention. The system is suitable for calibrating power quality monitoring equipment in a distribution station area.

[0169] like Fig. 9 As shown, the system includes: a program-controlled power source 910, an EUT 920, a clock source 930 and a host computer 940;

[0170] Wherein, the program-controlled power source 910 is used to receive the configuration instruction of the signal parameter information of the host computer and output a three-phase voltage signal to the EUT;

[0171] The EUT 920 is used to receive a three-phase voltage signal, obtain an actual verification signal of a signal source, and transmit the three-phase voltage signal and the actual verification signal to the host computer; wherein the three-phase voltage signal and the actual verification signal correspond to corresponding signal parameter information respectively;

[0172] The host computer 940 is used to execute the verification method of the power quality monitoring equipment of the distribution station area as described in any one of the embodiments of the present invention;

[0173] The clock source 930 is used to periodically output a stable and accurate time signal to synchronize the time of the programmable power source and the clock source, and the time of the EUT and the clock source.

[0174] In one embodiment, the clock source 930 outputs a time signal through an RS485 communication line and transmits it to the programmable power source 910 and the EUT920; the programmable power source 910 and the EUT920 communicate with the host computer 940 via Ethernet respectively; the clock source 930 is connected to the programmable power source 910 and the EUT920 respectively; the programmable power source 910 is connected to the host computer 940 and the power quality monitoring device EUT920; the EUT920 is connected to the host computer 940.

[0175] The calibration system for power quality monitoring equipment in a distribution station area provided in an embodiment of the present invention can execute the calibration method for power quality monitoring equipment in a distribution station area provided in any embodiment of the present invention, and has functional modules and beneficial effects corresponding to the execution method.

[0176] In this embodiment, PPS is a programmable power source, which receives the setting instructions of the PC and outputs the test signal to the EUT. This power source is selected as NETWAVE20, which can provide a continuous, stable and accurate three-phase voltage signal. The output signal waveform can be edited, that is, its output frequency, amplitude, phase, etc. can be programmed, and a predetermined waveform can be output at a specific time point and time period.

[0177] EUT is the equipment under test and power quality monitoring equipment. It receives, monitors, measures and verifies signals and provides measurement data to personal computers and PCs. SPT is a clock source. It can receive satellite signals and periodically output stable and accurate time signals. It outputs time information to PPS and EUT through RS485 communication lines. The time information format is IRGB encoding and is output once per second. It can synchronize the time values ​​of multiple devices once per second. This is a commonly used device to ensure that the timing of PPS and EUT is consistent. High-frequency clock crystals are often used as timing sources inside EUT, and the timing accuracy can reach 10ppm, that is, the error within 1 second is less than 10 microseconds. The host computer is a computer and the core of the detection process. It sends configuration instructions to PPS and EUT, collects the measurement data of EUT, analyzes and gives verification conclusions. Specifically, edit the parameters of the PPS calibration voltage signal (frequency, amplitude, phase, harmonics, interharmonics, modulation frequency, modulation amplitude, etc.), control the time when the PPS outputs the calibration signal, collect the 10-cycle data and 150-cycle data of the EUT's output, analyze whether it is synchronous sampling with the industrial frequency, analyze whether the effective value, harmonic value, and interharmonic are accurate, whether there are any sampling value omissions or overlaps, whether there are aggregation omissions or overlaps, whether the timing count is synchronized at 10 minutes, etc., and finally provide a calibration report.

[0178] In order to better understand the verification process, in this embodiment, the standard characteristic value group of the base frequency 49.46Hz and the actual detection item group of the base frequency 50.58Hz are used as examples for explanation. The characteristic value group of the base frequency 49.46Hz has the following configuration parameters: V_b=100, V_h=10, V_i=20, F_b=49.46, F_m=1.2365, A_m=0.2, N_har=13, N_ihar=13.1, F_b=49.46Hz, F_h=N_har×F_b, F_i=N_ihar×F_b. After execution, the following detection items, comparison values, and characteristic values ​​are obtained: the number of cyc10 values ​​belonging to 10 minutes Num_cyc10_10min=2968, Num_sec3_10min=198; the sequence length of the sec3 value sequence Q value Num_sec3_Q=196 is calculated.

[0179] Table 1. 10-minute 10-cycle and 150-cycle value sequences

[0180]

[0181] Table 2. Q values ​​for detecting abnormalities in 10-cycle and 150-cycle value sequences

[0182]

[0183]

[0184] Table 3. Cyc10 and sec3 values ​​for detecting the last number of the 10-minute time interval

[0185]

[0186] Table 4. Q values ​​for detecting overlap across 10 minutes

[0187]

[0188] In this embodiment, the actual detection item group of the fundamental frequency 50.58Hz: the configuration parameters include: V_b=100, V_h=10, V_i=20, F_b=50.58, F_m=1.2645, A_m=0.2, N_har=13, N_ihar=13.1, F_b=49.46Hz, F_h=N_har×F_b, F_i=N_ihar×F_b. After execution, the following detection items, comparison values, and characteristic values ​​are obtained. In this embodiment, F_b represents the fundamental frequency, V_b represents the fundamental amplitude, V_h represents the harmonic amplitude, F_h represents the harmonic frequency, F_i represents the interharmonic frequency, V_i represents the interharmonic amplitude, A_m represents the modulation depth, F_m represents the modulation frequency, N_har represents the harmonic order, and N_ihar represents the interharmonic order.

[0189] The number of cyc10 values ​​belonging to 10 minutes Num_cyc10_10min=3055; the number of sec3 values ​​Num_sec3_10min=203. The sequence length Num_sec3_Q=200 of the sec3 value sequence Q value is calculated.

[0190] Table 5. 10-minute 10-cycle and 150-cycle value sequences

[0191]

[0192] Table 6. Q values ​​for detecting abnormalities in 10-cycle, 150-value sequences

[0193]

[0194] Table 7. Cyc10 and sec3 values ​​for detecting the last number of the 10-minute time interval

[0195]

[0196] Table 8. Q values ​​for detecting overlap across 10 minutes

[0197]

[0198] In this embodiment, the detection is started, the fundamental voltage amplitudes V_b, V_h, V_i, F_b, F_m, F_h, F_i, A_m, N_har, and N_ihar are selected, and each standard characteristic value is calculated. Fig.10 Connect each device and power on. Set the above parameters as the parameters of the output voltage signal of PPS. Also, starting from 0:00:00, each phase outputs the unmodulated fundamental signal S_b. Starting from 0:10, phase A outputs the S_bm signal, phase B outputs the S_hm signal, and phase C outputs the S_im signal, that is, outputs the modulated signal. Set the time value of SPT to 0:00:00. Synchronize the clock of PPS with SPT, and synchronize the clock of EUT with SPT. Turn on the voltage signal output switch of PPS. Start the calibration software of PC, and start collecting the cyc10 value and sec3 value measured by EUT, store them separately while collecting, and sort them by the time stamp of each value. When the SPT time reaches 0:21, start the following analysis and calibration.

[0199] Basic verification: record the first sec3 value at 0:09, with A phase marked as Sec3_A, B phase marked as Sec3_B, and C phase marked as Sec3_C. These values ​​are the measured values ​​of the EUT for the unmodulated signal output by the PPS, the error values ​​used to calculate the EUT measured values ​​and PPS output values, and the measured values ​​and aggregate values ​​used to correct the EUT in subsequent verification items. Under normal circumstances, these relative error values ​​should be less than plus or minus (0.5% × 60%). If they exceed, an abnormality will be reported and the verification will be stopped. For example, if the PPS output amplitude is set to a voltage signal of 100V, if the EUT is measured to be 100.3V, it is also qualified, but there is an error of 0.3%. If 100.3V is corrected by 0.3%, a value very close to 100V can be obtained.

[0200] Statistics are made on the time stamp of the measurement data collected from the EUT. The minute value of the time stamp is equal to the number of cyc10s Num_cyc10_10min of a certain min10 (the tens digit of the time stamp minute value is the same when calculating the sampling value of each cyc10 value. For example, when the base frequency is 50Hz, the first is 0:10:00, the second is 0:10:0.2, the third is 0:10:0.6, the 300th is 0:10:59.8, the 301st is 0:11:0, the 302nd is 0:11:0.2, and the 3000th is 0:19:59.8). These two values ​​can be obtained by calculating the sampling interval T_s and the time length; statistics are made on the number of cyc10s and the number of sec3s between 0:10 and 0:20. Determine whether the number of cyc10 values ​​is equal to Num_cyc10_10min, and whether the number of sec3 values ​​is equal to Num_sec3_10min. If they are not equal, report such abnormality and stop the test.

[0201] Calculate the relative error between each cyc10 value collected from 0:10 to 0:20 and the standard characteristic value. The absolute value of the error value should not be greater than (0.5% × 60%) to ensure that the error does not exceed 0.5% when the equipment is used in batches. During the verification, it is limited to 60% of the agreed value. The number of comparisons is Num_cyc10_10min. If it exceeds the standard, the serial number of the error value is reported and the verification is stopped. The cyc10 value of phase A is compared with Cyc10_bm, the cyc10 value of phase B is compared with Cyc10_hm, and the cyc10 value of phase C is compared with Cyc10_im.

[0202] Calculate the relative error between each sec3 value collected from 0:10 to 0:20 and the standard characteristic value. The absolute value of the error value should not be greater than (0.5% × 60%). The number of comparisons is Num_sec3_10min. If it exceeds the standard, report the number of the error value and stop the test. The comparison of phase A is Sec3_bm, the comparison of phase B is Sec3_hm, and the comparison of phase C is Sec3_im. Note that the last sec3 value from 0:10 to 0:20 is Sec3_bmZ, Sec3_hmZ, and Sec3_imZ.

[0203] After the basic verification is qualified, the calculation of cyc10 values ​​is verified to see if there are any missing or overlapping sampling values. After the above verifications are qualified, this step is performed to identify whether the EUT uses only a few cyc10 values ​​instead of 15 or uses repeated cyc10 values ​​when aggregating sec3. The specific verification method has been given in the above steps, and this embodiment will not be described separately here.

[0204] In one embodiment, Fig.10 A schematic diagram of overlapping verification of 10-cycle and 150-cycle power quality parameters provided by an embodiment of the present invention. Fig.10 As shown in the figure, the basic measurement cycle is 10 cycles. Within the duration of 10 power grid cycles, the voltage signal is evenly sampled, for example, 256 times per cycle, and a total of 2560 values ​​are sampled. The voltage effective value, harmonic value, and interharmonic value are calculated from these 2560 sampled values, and the start sampling time and sequence number are recorded. The five parameters are used to identify the power quality characteristics of the 10-cycle voltage signal. The 150-cycle effective value aggregation algorithm is to aggregate and calculate 15 consecutive, non-overlapping 10-cycle effective values. The harmonic value and interharmonic value are also calculated in this way, and the sequence number and the start time of the first 10-cycle are recorded. The parameters are used to identify the power quality characteristics of the 150-cycle voltage signal. Illustratively, in this embodiment, k=Num_cyc10_10min and n=Num_sec3_10min are used as examples for explanation, wherein k=Num_cyc10_10min represents the number of 10-cycle value sequences within the present 10 minutes, and n=Num_sec3_10min represents the number of 150-cycle value sequences within the present 10 minutes.

[0205] like Fig.10As shown, at the beginning of every 10 minutes, the timing of cyc10 and the counting of sec3 begin. When the first cyc10 duration ends, the effective value, harmonic value, and interharmonic value are inferred through the series of voltage signal values ​​sampled during this duration, and the timing, sampling, and calculation of the second cyc10 begin, and continue. When 15 cyc10s are sampled, the first sec3 value is aggregated with the first 15 cyc10 values, and the collection and calculation continue. Before the end of this 10 minutes, each cyc10 duration is continuous and non-overlapping, and each sec3 is also continuous and non-overlapping. At the end of this 10 minutes, the cyc10 that has not ended continues to be timed until it ends, and the sec3 that has not ended continues to be counted. As shown Figure 2 As shown in the overlap 1, the two cyc10s before and after 10 minutes will overlap part of the time period, and the signal sampling value in the overlapping time period will be used twice. The two sec3s before and after 10 minutes will also have overlapping time periods, as shown in the overlap 2 in the figure, the last two cyc10s of the last sec3 before 10 minutes and the first two cyc10s of the first sec3 after 10 minutes are completely overlapped. Verifying these two kinds of overlaps is also the focus of verification. Through the verification method in this embodiment, overlaps can be verified.

[0206] right Fig.10 The overlap 1 in the test is: Fig.10 It can be seen that at each min10 moment, the first cyc10 of the current 10 minutes and the last cyc10 of the previous 10 minutes have a partial overlap, but the overlapping duration is less than cyc10, and the sampling values ​​within this duration will be reused. This step is designed to detect whether the sampling values ​​are correctly overlapped and used. This step is only performed if the last cyc10 value of min10 has been verified to be qualified. Specifically, the cyc10 valid value sequence collected from the EUT is used, according to its time stamp, and Q_cyc10_bmZ is calculated according to the above verification method. The value should not be greater than 1.5 times the ideal value and not less than 0.5 times the ideal value, otherwise an abnormality is reported. The method for verifying Q_cyc10_hmZ and Q_cyc10_imZ is similar.

[0207] right Fig.10 The overlap 2 in the test is: Fig.10It can be seen that one or several cyc10 values ​​starting at each min10 moment may be reused: aggregated by the last sec3 value of the previous 10 minutes, and aggregated by the first sec3 value of this 10 minutes. This step is designed to detect whether the cyc10 values ​​are correctly overlapped. This step is only performed if the last sec3 value of min10 has been verified to be qualified. Specifically, the sec3 valid value sequence collected from the EUT is used, and Q_sec3_bmZ is calculated according to its time stamp according to the above verification method. The value should not be greater than 1.5 times the ideal value and not less than 0.5 times the ideal value, otherwise an abnormality is reported. The method for verifying Q_sec3_hmZ and Q_sec3_imZ is similar.

[0208] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0209] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calibrating power quality monitoring equipment in a distribution station area, characterized in that: The method comprises: Acquire signal parameter information of a preconfigured three-phase voltage signal, and determine an optimal modulation frequency based on the signal parameter information; Generate standard characteristic value sequences corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality verification within a preset time interval based on the optimal modulation frequency; Obtaining a 10-cycle measured value sequence and a 150-cycle measured value sequence corresponding to an actual verification signal actually output by the power quality monitoring equipment EUT, and determining actual characteristic value sequences corresponding to the 10-cycle measured value sequence and the 150-cycle measured value sequence respectively; Based on the standard characteristic value sequence and the actual characteristic value sequence, a verification result of the actual verification signal measurement result output by the power quality monitoring equipment in the distribution station area is determined, and a verification report is generated based on the verification result.

2. The method according to claim 1, characterized in that The signal parameter information includes at least one of the following: fundamental frequency, fundamental amplitude, harmonic amplitude, harmonic order, harmonic frequency, interharmonic amplitude, interharmonic order, interharmonic frequency, modulation depth, number of sampling values ​​within a 10-cycle measurement period, and the time value of each sampling value.

3. The method according to claim 2, characterized in that The determining the optimal modulation frequency based on the signal parameter information comprises: Constructing a fundamental wave signal according to the number of sampling values ​​in each of the 10-cycle measurement periods, the time value of each sampling value, the fundamental wave amplitude and the fundamental wave frequency, and randomly selecting a modulation frequency from the preset modulation frequencies as the current modulation frequency; wherein the preset modulation frequency is constructed from the fundamental wave frequency; Determine a modulation signal corresponding to the current modulation frequency, and construct a fundamental modulation signal by using the modulation signal and the fundamental signal; Determine a 10-cycle effective value sequence corresponding to all sampling values ​​in each of the 10-cycle measurement periods according to the fundamental wave modulation signal, perform Fourier transform FFT analysis on the 10-cycle effective value sequence to obtain a corresponding first spectrum array, and select a frequency point with the largest power spectrum density from the first spectrum array to perform energy enhancement to obtain a first enhancement value; The first 10-cycle effective value in the 10-cycle effective value sequence is modified to obtain an abnormal 10-cycle effective value sequence, and the abnormal 10-cycle effective value sequence is subjected to FFT analysis to obtain a corresponding second spectrum array, and a frequency point with the largest power spectrum density is selected from the second spectrum array to perform energy enhancement to obtain a second enhancement value; determining a ratio of the first enhancement value to the second enhancement value, and taking the ratio as a candidate enhancement value and storing it in a candidate enhancement value list; Select the next modulation frequency from the preset modulation frequencies, and use the next modulation frequency as the current modulation frequency, return to the step of determining the modulation signal corresponding to the current modulation frequency to calculate the next candidate enhancement value, until all preset modulation frequencies are traversed, and a candidate enhancement value list including at least two candidate enhancement values ​​is obtained, the maximum candidate enhancement value is selected from the candidate enhancement value list, and the modulation frequency corresponding to the maximum candidate enhancement value is used as the optimal modulation frequency.

4. The method according to claim 3, characterized in that The energy enhancement methods include: Determine a first amplitude and a second amplitude respectively corresponding to two frequency points adjacent to the frequency point having the maximum power spectrum density; Calculating a cumulative sum of the first amplitude and the second amplitude; The ratio of the amplitude of the frequency point with the largest power spectrum density to the accumulated sum is used as the enhancement value.

5. The method according to claim 3, characterized in that: Selecting a maximum candidate enhancement value from the candidate enhancement value list includes: Sorting all candidate enhancement values ​​included in the candidate enhancement value list according to the size of the candidate enhancement values ​​to obtain a sorting result; A candidate enhancement value with the largest ranking is selected from the ranking results as the maximum candidate enhancement value.

6. The method according to claim 1, characterized in that The standard characteristic value sequence includes standard characteristic values, and corresponding verification values ​​and time scales corresponding to each of the standard characteristic values; The standard characteristic values ​​include: a 10-cycle value sequence, an enhanced value of the 10-cycle value sequence, a 10-cycle overlapping value, and an enhanced value of the 10-cycle overlapping value; 150 frequency value sequence, enhanced value of the 150 frequency value sequence, 150 frequency overlapping value, enhanced value of the 150 frequency overlapping value.

7. The method according to claim 6, characterized in that The 10-cycle value sequence includes a 10-cycle effective value sequence, a 10-cycle harmonic value sequence, and a 10-cycle interharmonic value sequence; The enhancement value of the 10-cycle value sequence includes: the enhancement value of the 10-cycle effective value sequence, the enhancement value of the 10-cycle harmonic value sequence, and the enhancement value of the 10-cycle interharmonic value sequence; wherein the enhancement value of the 10-cycle effective value sequence is the maximum candidate enhancement value corresponding to the optimal modulation frequency; The 10-cycle overlap value includes: 10-cycle effective value overlap value, 10-cycle harmonic value overlap value, and 10-cycle interharmonic value overlap value; The enhancement value of the 10-cycle overlapping value includes: the enhancement value of the overlapping value of the 10-cycle effective value, the enhancement value of the overlapping value of the 10-cycle harmonic value, and the enhancement value of the overlapping value of the 10-cycle interharmonic value.

8. The method according to claim 6, characterized in that The 150-cycle value sequence includes: a 150-cycle effective value sequence, a 150-cycle harmonic value sequence, and a 150-cycle interharmonic value sequence; The enhanced values ​​of the 150-cycle value sequence include: the enhanced values ​​of the 150-cycle effective value sequence, the enhanced values ​​of the 150-cycle harmonic value sequence, and the enhanced values ​​of the 150-cycle interharmonic value sequence; 150-cycle overlap value: 150-cycle effective value overlap value, 150-cycle harmonic value overlap value, 150-cycle interharmonic value overlap value; The enhancement value of the 150-cycle overlapping value includes: the enhancement value of the overlapping value of the 150-cycle effective value, the enhancement value of the overlapping value of the 150-cycle harmonic value, and the enhancement value of the overlapping value of the 150-cycle interharmonic value.

9. The method according to any one of claims 7 or 8, characterized in that: Based on the optimal modulation frequency, a standard characteristic value sequence corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality verification within a preset time interval is generated, including: Using the optimal modulation frequency to construct a fundamental modulation signal, a harmonic modulation signal and an interharmonic modulation signal; Counting the number of 10-cycle values, the number of 150-cycle values, the number of 10-cycle value sequences corresponding to each 10-cycle value, and the number of 150-cycle value sequences corresponding to each 150-cycle value within the preset time interval; Obtain a 10-cycle effective value sequence through the fundamental wave modulation signal and the number of sampling values ​​per cycle within the preset time interval, and aggregate the 10-cycle effective value sequence into a 150-cycle effective value sequence to obtain at least one 150-cycle effective value sequence; Obtaining a 10-cycle harmonic value sequence through the harmonic modulation signal and the number of harmonic values ​​corresponding to each cycle within the preset time interval, and aggregating the 10-cycle harmonic value sequence into a 150-cycle harmonic value sequence to obtain at least one 150-cycle harmonic value sequence; A 10-cycle interharmonic value sequence is obtained by summing the interharmonic modulation signal and the number of interharmonic values ​​per cycle within the preset time interval, and the 10-cycle interharmonic value sequence is aggregated into a 150-cycle interharmonic value sequence to obtain at least one 150-cycle interharmonic value sequence.

10. The method according to claim 7, characterized in that The 10-cycle effective value sequence includes effective values ​​and time scales corresponding to the effective values, and the 150-cycle effective value sequence includes effective values ​​and time scales corresponding to the effective values; The 10-cycle harmonic value sequence includes harmonic values ​​and time scales corresponding to the harmonic values, and the 150-cycle harmonic value sequence includes harmonic values ​​and time scales corresponding to the harmonic values; The 10-cycle interharmonic value sequence includes interharmonic values ​​and time scales corresponding to the interharmonic values, and the 150-cycle interharmonic value sequence includes interharmonic values ​​and time scales corresponding to the interharmonic values.

11. The method according to claim 9, characterized in that Based on the optimal modulation frequency, a standard characteristic value sequence corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality verification within a preset time interval is generated, including: Performing FFT analysis on the 10-cycle harmonic value sequence to obtain a third spectrum array, calculating third enhancement values ​​corresponding to each frequency point in the third spectrum array, and selecting a maximum enhancement value from the third enhancement values ​​as the enhancement value of the 10-cycle harmonic value sequence; Performing FFT analysis on the 10-cycle interharmonic value sequence to obtain a corresponding fourth spectrum array, calculating fourth enhancement values ​​corresponding to each frequency point in the fourth spectrum array, and selecting a maximum enhancement value from the fourth enhancement values ​​as the enhancement value of the 10-cycle interharmonic value sequence; The numbers corresponding to the 150-cycle effective value sequence, the 150-cycle harmonic value sequence, and the 150-cycle interharmonic value sequence within a preset time interval are divided into a preset continuous number of continuous value sequences in turn, and FFT analysis is performed on each of the continuous value sequences to obtain the corresponding fifth spectrum arrays, and the fifth enhancement value corresponding to each frequency point in each of the fifth spectrum arrays is calculated, and the largest enhancement value is selected from each of the fifth enhancement values ​​as the enhancement value corresponding to the 150-cycle effective value sequence, the 150-cycle harmonic value sequence, and the 150-cycle interharmonic value sequence, respectively.

12. The method according to claim 9, characterized in that The method of generating standard characteristic value sequences corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality verification within a preset time interval based on the optimal modulation frequency includes: Calculate the number of 10-cycle value sequences from the first preset time to the second preset time, record the number of the 10-cycle value sequences as N, and use the Nth value of the 10-cycle value sequence as the 10-cycle overlap value; wherein the Nth value is the last 10-cycle value corresponding to the 10-cycle value sequence belonging to the first preset time; Starting from the first 10-cycle values ​​in the 10-cycle value sequence within the first preset time to the second preset time, a preset number of 10-cycle values ​​are divided into a group for calculating 150-cycle values. When the number of 10-cycle values ​​in the last group is less than the preset number, the number of 10-cycle values ​​in the last group is recorded as the first number of 10-cycle values, and a second number of 10-cycle values ​​are selected from the 10-cycle value sequence starting from the second preset time, and the first number of 10-cycle values ​​and the second number of 10-cycle values ​​are sequentially aggregated into a 150-cycle overlapping value.

13. The method according to claim 12, characterized in that The method of generating standard characteristic value sequences corresponding to a 10-cycle value sequence and a 150-cycle value sequence for power quality verification within a preset time interval based on the optimal modulation frequency includes: Selecting a third number of 10-cycle values ​​from the 10-cycle value sequence from the first preset time to the second preset time, and selecting a fourth number of 10-cycle values ​​from the 10-cycle value sequence starting from the second preset time, sequentially combining the third number of 10-cycle values ​​and the fourth number of 10-cycle values ​​into a target 10-cycle value sequence, performing FFT analysis on the target 10-cycle value sequence to obtain a corresponding sixth frequency spectrum array, calculating sixth enhancement values ​​corresponding to each frequency point in the sixth frequency spectrum array, and selecting the largest enhancement value from the sixth enhancement values ​​as the enhancement value of the 10-cycle overlap value; Every 15 10-cycle values ​​from the first preset time to the second preset time are aggregated to obtain the corresponding 150-cycle value, and a target 150-cycle value sequence is formed from each of the 150-cycle values. FFT analysis is performed on the target 150-cycle value sequence to obtain the corresponding seventh spectrum array, and the seventh enhancement value corresponding to each frequency point in the seventh spectrum array is calculated, and the largest enhancement value is selected from the seventh enhancement value as the enhancement value of the 150-cycle overlapping value.

14. The method according to claim 11, characterized in that The calculation method of the third enhancement value includes: Determine a third amplitude and a fourth amplitude respectively corresponding to two frequency points adjacent to the frequency point with the maximum power spectrum density in the third spectrum array; Calculating a cumulative sum of the third amplitude and the fourth amplitude; The ratio of the amplitude of the frequency point with the largest power spectrum density to the accumulated sum is used as the third enhancement value.

15. The method according to claim 11, characterized in that The calculation method of the fourth enhancement value includes: Determine a fifth amplitude and a sixth amplitude respectively corresponding to two frequency points adjacent to the frequency point with the largest power spectrum density in the fourth frequency spectrum array; Calculating a cumulative sum of the fifth amplitude and the sixth amplitude; The ratio of the amplitude of the frequency point with the largest power spectrum density to the accumulated sum is used as the fourth enhancement value.

16. The method according to claim 11, characterized in that The calculation method of the fifth enhancement value includes: Determine a seventh amplitude and an eighth amplitude respectively corresponding to two frequency points adjacent to the frequency point with the maximum power spectrum density in the fifth frequency spectrum array; Calculating a cumulative sum of the seventh amplitude and the eighth amplitude; The ratio of the amplitude of the frequency point with the largest power spectrum density to the accumulated sum is used as the fifth enhancement value.

17. The method according to claim 13, characterized in that The calculation method of the sixth enhancement value includes: Determine a ninth amplitude and a tenth amplitude respectively corresponding to two frequency points adjacent to the frequency point with the largest power spectrum density in the sixth frequency spectrum array; Calculating a cumulative sum of the ninth amplitude and the tenth amplitude; The ratio of the amplitude of the frequency point with the largest power spectrum density to the accumulated sum is used as the sixth enhancement value.

18. The method according to claim 13, characterized in that The calculation method of the seventh enhancement value includes: Determine an eleventh amplitude and a twelfth amplitude respectively corresponding to two frequency points adjacent to the frequency point with the maximum power spectrum density in the seventh frequency spectrum array; Calculating a cumulative sum of the eleventh amplitude value and the twelfth amplitude value; The ratio of the amplitude of the frequency point with the largest power spectrum density to the accumulated sum is used as the seventh enhancement value.

19. The method according to claim 1, characterized in that The step of determining the verification result of the actual verification signal output by the power quality monitoring device in the distribution station area based on the standard characteristic value sequence and the actual characteristic value sequence includes: Compare the number of 10-cycle value sequences and the number of 150-cycle value sequences in the standard characteristic value sequence within the preset time interval with the actual number of 10-cycle value sequences and the actual number of 150-cycle value sequences, respectively, and determine that the preliminary verification result is passed when the comparison is equal; Determine the error between the 10-cycle value sequence in the standard eigenvalue sequence and the actual 10-cycle value sequence in the actual eigenvalue sequence within a preset time interval, and the error between the 150-cycle value sequence in the standard eigenvalue sequence and the actual 150-cycle value sequence in the actual eigenvalue sequence, and determine that the preliminary verification result is passed if the error does not exceed a preset error threshold; Based on the preliminary verification result, a target verification result of an actual verification signal output by the power quality monitoring equipment in the distribution station area is determined.

20. The method according to claim 19, characterized in that The step of determining the target verification result of the actual verification signal output by the power quality monitoring equipment in the distribution station area based on the preliminary verification result includes: Determine a first verification result of the actual verification signal output by the power quality monitoring device in the distribution station area according to the enhanced value of the 10-cycle value sequence in the standard characteristic value sequence and the enhanced value of the actual 10-cycle value sequence of the actual characteristic value sequence; Determine a second verification result of the actual verification signal output by the power quality monitoring device in the distribution station area according to the enhanced value of the 150-cycle value sequence in the standard characteristic value sequence and the enhanced value of the actual 150-cycle value sequence of the actual characteristic value sequence; Determine a third verification result of the actual verification signal output by the power quality monitoring device in the distribution station area according to the enhanced value of the 10-cycle overlapping value in the standard characteristic value sequence and the enhanced value of the actual 10-cycle overlapping value in the actual characteristic value sequence; The fourth verification result of the actual verification signal output by the power quality monitoring equipment in the distribution station area is determined based on the enhanced value of the 150-cycle overlapping value in the standard characteristic value sequence, the enhanced value of the actual 150-cycle overlapping value in the actual characteristic value sequence, and the preset correction factor.

21. The method according to claim 20, characterized in that The first verification result of the actual verification signal output by the power quality monitoring device in the distribution station area is determined according to the enhanced value of the 10-cycle value sequence in the standard characteristic value sequence and the enhanced value of the actual 10-cycle value sequence of the actual characteristic value sequence, including: Count the total number of 10 cycles within the first preset time; wherein each 10 cycles corresponds to a corresponding actual eigenvalue sequence and a standard eigenvalue sequence; Starting from the first 10 cycles within the first preset time, determine whether the error between the enhanced value of the actual 10-cycle value sequence corresponding to the first 10 cycles to the last 10 cycles and the enhanced value of the 10-cycle value sequence in the standard feature value sequence is within a preset error threshold range; If it is within the preset error threshold range, it is determined that the test is normal, and it is continued to determine whether the time scale of the 10-cycle value sequence corresponding to the last 10 cycles is greater than or equal to the second preset time. If so, it is determined that the 10-cycle value sequence corresponding to each 10 cycles within the first preset time is qualified. If not, the second 10 cycles are selected from the first preset time, and the second 10 cycles are used as the first 10 cycles, and the step of returning to the judgment step of whether the error is within the preset error threshold range; If it is not within the preset error threshold range, it is determined that there is a calibration abnormality in the actual 10-cycle value sequence corresponding to the first 10 cycles to the last 10 cycles, and the calibration result is determined based on the preset first correction factor and the 10-cycle value sequence in the standard characteristic value sequence with the same time scale as the actual 10-cycle value sequence.

22. The method according to claim 21, characterized in that The method of determining the test result based on the preset first correction factor and the 10-cycle value sequence in the standard characteristic value sequence having the same time scale as the actual 10-cycle value sequence includes: Setting an abnormal sequence number for each of the 10 cycles of the detected abnormality, and selecting an abnormal sequence number as the current abnormal sequence number, using the 10-cycle value sequence in the standard characteristic value sequence with the same time scale from the first preset time to the second preset time, and the preset first correction factor to correct the actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number, and re-verifying the corrected actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number; Select the next abnormal sequence number from the abnormal sequence numbers, take the next abnormal sequence number as the current abnormal sequence number, and return to the step of correcting the actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number until the 10 cycles of all abnormal sequence numbers are verified and at least two actual 10-cycle value sequences with verification abnormalities are obtained.

23. The method according to claim 22, characterized in that The re-verification of the actual 10-cycle value sequence corresponding to the 10-cycle of the corrected current abnormal sequence number includes: Calculate the enhanced value of the actual 10-cycle value sequence corresponding to the 10-cycle value of the corrected current abnormal sequence number as the current enhanced value; Determine whether the error between the current enhancement value and the enhancement value of the 10-cycle value sequence with the same time scale in the standard feature value sequence is within a preset error threshold range; If so, determine that the actual 10-cycle value sequence corresponding to the 10-cycle current abnormal sequence number before correction is abnormal; If not, the actual 10-cycle value sequence corresponding to the 10-cycle value of the corrected current abnormal sequence number is restored.

24. The method according to claim 20, characterized in that The second verification result of determining the actual verification signal output by the power quality monitoring device in the distribution station area according to the enhanced value of the 150-cycle value sequence in the standard characteristic value sequence and the enhanced value of the actual 150-cycle value sequence of the actual characteristic value sequence includes: Counting the total number of 150 cycles within the first preset time; wherein each 150 cycles corresponds to a corresponding actual eigenvalue sequence and a standard eigenvalue sequence; Starting from the first 150 cycles within the first preset time, determining whether the error between the enhanced value of the actual 150-cycle value sequence corresponding to the first 150 cycles to the last 150 cycles and the enhanced value of the 150-cycle value sequence in the standard feature value sequence is within a preset error threshold range; If yes, it is determined that the test is normal, and whether the time scale of the 150-cycle value sequence corresponding to the last 150 cycles is greater than or equal to the second preset time is continued to be determined. If it is greater than or equal to the second preset time, it is determined that the 150-cycle value sequence corresponding to each 150 cycles within the first preset time is qualified. If it is less than the second preset time, the second 150 cycles are selected from the first preset time, and the second 150 cycles are used as the first 150 cycles, and the step of determining whether the error is within the preset error threshold range is returned; If not, it is determined that there is a calibration abnormality in the actual 150-cycle value sequence corresponding to the first 150 cycles to the last 150 cycles, and the calibration result is determined based on the preset second correction factor and the 150-cycle value sequence in the standard characteristic value sequence with the same time scale as the actual 150-cycle value sequence.

25. The method according to claim 24, characterized in that The method of determining the test result based on the preset second correction factor and the 150-cycle value sequence in the standard characteristic value sequence having the same time scale as the actual 150-cycle value sequence includes: An abnormal sequence number is set for each 150 cycles of the detected abnormality, and an abnormal sequence number is selected as the current abnormal sequence number, and the actual 10-cycle value sequence corresponding to the 150 cycles of the current abnormal sequence number is corrected using the 150-cycle value sequence in the standard characteristic value sequence with the same time scale from the first preset time to the second preset time, and the preset second correction factor, and the actual 150-cycle value sequence corresponding to the 150 cycles of the current abnormal sequence number after correction is re-verified; Select the next abnormal sequence number from the abnormal sequence numbers, take the next abnormal sequence number as the current abnormal sequence number, and return to the step of correcting the actual 150-cycle value sequence corresponding to the 150 cycles of the current abnormal sequence number, until the 150-cycle verification of all abnormal sequence numbers is completed, and at least two actual 150-cycle value sequences with verified abnormalities are obtained.

26. A calibration system for power quality monitoring equipment in a distribution station area, characterized in that: The system comprises: a program-controlled power source, an electric energy quality monitoring device EUT, a clock source and a host computer; Wherein, the program-controlled power source is used to receive the configuration instructions of the signal parameter information of the host computer and output a three-phase voltage signal to the EUT; The EUT is used to receive a three-phase voltage signal, obtain an actual verification signal of a signal source, and transmit the measurement results of the three-phase voltage signal and the actual verification signal to the host computer; wherein the three-phase voltage signal and the actual verification signal correspond to corresponding signal parameter information respectively; The host computer is used to execute the verification method of the power quality monitoring equipment of the distribution station area according to any one of claims 1 to 25; The clock source is used to periodically output a stable and accurate time signal to synchronize the time of the programmable power source with the clock source, and the time of the EUT with the clock source.

27. The system according to claim 26, characterized in that The clock source outputs a time signal through an RS485 communication line and transmits it to the program-controlled power source and the EUT; The program-controlled power source and the EUT communicate with the host computer via Ethernet respectively; The clock source is connected to the program-controlled power source and the EUT respectively; the program-controlled power source is connected to the host computer and the EUT; and the EUT is connected to the host computer.

28. The system according to claim 26, characterized in that The host computer comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the calibration method of the power quality monitoring equipment in the distribution station area according to any one of claims 1-25.

29. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the calibration method of the power quality monitoring equipment in the distribution station area according to any one of claims 1-25 when executed.

30. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the computer program implements the verification method of the power quality monitoring device of the distribution station area according to any one of claims 1-25.

Images