A method and system for verifying power quality monitoring equipment in a distribution station area

Abstract

The present invention discloses a calibration method and system for power quality monitoring equipment in a distribution station area. The method includes: determining the optimal modulation frequency based on the acquired signal parameter information, generating standard characteristic value sequences corresponding to 10 cycles and 150 cycles respectively for power quality calibration within a preset time interval based on the optimal modulation frequency, obtaining the 10-cycle measured value sequence and the 150-cycle measured value sequence actually output by the EUT, determining the actual characteristic value sequence corresponding to the 10-cycle measured value sequence and the 150-cycle measured value sequence respectively; and determining the calibration result based on the standard characteristic value sequence and the actual characteristic value sequence. In an embodiment of the present invention, by determining the optimal modulation frequency, generating the corresponding standard characteristic value sequence based on the optimal modulation frequency, and determining the calibration result based on the standard characteristic value sequence and the actual characteristic value sequence, it is possible to calibrate whether the sampling value is omitted or reused and whether the 10-cycle value is omitted or reused, thereby improving the accuracy and precision of the calibration.

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 of varying amplitude on the voltage fundamental. However, because the harmonics are modulated using a rectangular wave with a modulation period greater than 10 cycles, it's possible to use a single 10-cycle measurement value instead of several 10-cycle measurements. 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 will differ, but both are steady-state signals. This can also result in gapped measurements. Using these 10-cycle values for overvoltage and undervoltage analysis may not achieve the desired results. In the actual operating environment of power quality testing equipment, the monitored voltage signal is not steady-state but rather complex, variable, and gradually changing. Using gapped or slip measurements will result in measurement data that fails to reflect the actual voltage signal conditions at each time period, significantly reducing calibration accuracy and precision. 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, based on the optimal modulation frequency, 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;

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

[0009] 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, and a verification report is generated based on the verification result.

[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 programmable power source, a power quality monitoring device EUT, a clock source, and a host computer;

[0011] Wherein, the programmable 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 configured to receive a three-phase voltage signal and obtain an actual verification signal from a signal source, and transmit 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 respectively correspond to corresponding signal parameter information;

[0013] The host computer 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;

[0014] The clock source 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 is synchronized.

[0015] The technical solution of the embodiment of the present invention determines the optimal modulation frequency based on the acquired signal parameter information, thereby making the modulation signal characteristics 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 each 10 cycles and the actual measured value sequence of each 150 cycles of the EUT actual output are obtained, and the actual measured value sequence of each 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, a variety of 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 beneficial to data analysis, accident investigation and use.

[0016] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily 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 one embodiment of the present invention;

[0019] Figure 2 A schematic diagram of a fundamental wave modulation signal waveform provided by one 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 flowchart of another method for calibrating power quality monitoring equipment in a distribution station area provided by one embodiment of the present invention;

[0022] Figure 5 A flowchart 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 10-cycle value measurements provided by an embodiment of the present invention;

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

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

[0027] Figure 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 solutions of the present invention, the technical solutions 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 embodiments described 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 making creative efforts should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first", "second", etc. in the description 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 numbers 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 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 This is a flowchart of a calibration method for power quality monitoring equipment in a distribution substation area provided by an embodiment of the present invention. This embodiment is applicable to the situation when calibrating power quality monitoring equipment in a distribution substation area. The method can be executed by the host computer in the calibration system of the power quality monitoring equipment in the distribution substation area.

[0031] like Figure 1As shown, the verification method of the power quality monitoring equipment in the distribution station area in this embodiment includes the following specific 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] 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, the number of sample values within a 10-cycle measurement period, and the time value of each sample value. In addition, it may 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. For example, the fundamental amplitude is set to 100, the harmonic order is set to 14, the modulation depth is set to 0.2, the number of sample values within a 10-cycle measurement period is 256, etc., which can be configured according to needs. In this embodiment, 1 cycle can correspond to multiple consecutive sample values of time-scale values, 10 consecutive 1-cycle sample values can form 10 cycles, and 15 10 cycles can be combined into 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 the 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). Transformation) analysis is performed to obtain the analysis result, and 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 that misses one sampling value. The abnormal 10-cycle effective value sequence is subjected to FFT analysis, and 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 enhanced 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] Among them, the preset time interval can be 10 minutes each, or it can be a time interval set according to needs. For example, the preset time interval can be set from 0:10 to 0:20, and this embodiment does not limit 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 corresponds to a corresponding 10-cycle standard characteristic value sequence, and every 15 10-cycles can be aggregated into a 150-cycle, and each 150-cycle also corresponds to a corresponding standard characteristic value sequence. Among them, the standard characteristic values include: a 10-cycle value sequence (also known as a cyc10 value sequence), an enhanced value of a 10-cycle value sequence (also known 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 value of the 10-cycle value sequence includes: 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 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 overlap values include: 10-cycle effective value overlap value (also called Cyc10_bmZ), 10-cycle harmonic value overlap value (also called Cyc10_hmZ), 10-cycle interharmonic value overlap value (also called Cyc10_imZ); 150-cycle overlap value: 150-cycle effective value overlap value (also called Sec3_bmZ), 150-cycle harmonic value overlap value (also called Sec3_hmZ), 150-cycle interharmonic value overlap value (also called Sec3_imZ); The enhanced value of the 10-cycle overlap value includes: 10-cycle effective value overlap 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, different methods can be used to generate standard characteristic value sequences corresponding to 10 cycles and 150 cycles for power quality verification within a preset time interval. In some embodiments, the optimal modulation frequency is used to construct the fundamental modulation signal, the harmonic modulation signal, and the interharmonic modulation signal. 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. Then, 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 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 represent 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, and so on. In some embodiments, FFT analysis can be performed on 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, respectively, to calculate the amplitude of each frequency point and the enhancement value of each frequency point, thereby obtaining 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 aggregated 150-cycle effective value sequence, the 150-cycle harmonic value sequence, and the 150-cycle interharmonic value sequence 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 Q_rms_max is used 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 can be 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 insufficient 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 a 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 sequentially combined into a target 10-cycle value sequence 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. Obtain a 10-cycle measured value sequence and a 150-cycle measured value sequence corresponding to the actual test signal actually output by the EUT, and determine the actual characteristic value sequences corresponding to the 10-cycle measured value sequence and the 150-cycle measured value sequence, respectively.

[0041] The power quality monitoring equipment (Equipment Under Test, EUT), which can also be referred to as the device under test (DUT), refers to a device under test that receives, detects, and measures actual signals. The DUT 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. A 150-cycle measured value is synthesized from 15 temporally consecutive 10-cycle measured values, 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 interharmonic value overlap value; the actual 150-cycle overlap value includes: the actual 150-cycle effective value overlap value, the actual 150-cycle harmonic value overlap value, and the actual 150-cycle interharmonic value overlap value; the enhanced value of the actual 10-cycle overlap value includes: the enhanced value of the actual 10-cycle effective value overlap value, the enhanced value of the actual 10-cycle harmonic value overlap value, and the enhanced value of the actual 10-cycle interharmonic value overlap value; the enhanced value of the actual 150-cycle overlap value includes: the enhanced value of the actual 150-cycle effective value overlap value, the enhanced value of the actual 150-cycle harmonic value overlap value, and the enhanced value of the actual 150-cycle interharmonic value overlap 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 can be determined for use in 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 enhancement 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 to calculate the amplitude of each frequency point and the enhancement value of each frequency point, 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 verification result of the actual verification signal measurement result output by the power quality monitoring equipment in the distribution station area based on the standard characteristic value sequence and the actual characteristic value sequence, and generate a verification report based on the verification 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 or abnormal test. Of course, the test abnormality 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 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 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 conditions such as whether overlap or omission occurs within a preset time interval. 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 results and the judgment results can be output to generate a test report. This embodiment does not impose any restrictions here.

[0048] The technical solution of the embodiment of the present invention determines the optimal modulation frequency based on the acquired signal parameter information, thereby making the modulation signal characteristics 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 cycles and 150 cycles for power quality verification within a preset time interval is generated, and the actual measured value sequence of each 10 cycle and the actual measured value sequence of 150 cycles actually output by the EUT are 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] Generally, the minimum granularity of harmonic frequencies is an integer multiple of the fundamental frequency, and the minimum granularity of interharmonic frequencies is 0.1 times the fundamental frequency. Therefore, the number of harmonics and interharmonics within any 10-cycle period is the same and an integer. This also means that the effective value, harmonic value, and interharmonic value of any 10-cycle period are also the same. Therefore, for the 150-cycle aggregate value, one or more 10-cycle values may be used to replace it, because the result of aggregating any 10-cycle values is the same. However, in actual field operation, voltage signals are complex and changeable, and the fundamental amplitude, harmonic amplitude, and interharmonic amplitude often vary with time. Therefore, power quality monitoring equipment should strictly comply with the standards, and the verification system should also have the following capabilities: the ability to identify whether sample values are missed or reused during the sampling process; the ability to detect whether 10-cycle values are missed or reused when aggregating 150-cycle values. To this end, we should go beyond the standard agreement and make the value of each 10-cycle wave of the calibration signal change and be different within a longer period of time, and then conduct 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 is shown in FIG. 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 the 10-cycle effective value, the 10-cycle harmonic value, or the 10-cycle interharmonic value). The waveform diagram of the change of the 10-cycle effective value is shown in Figure 3As shown, the period of the cyc10 value change is essentially synchronized with the modulation frequency (approximately 2 × 1.2645 = 2.529 changes in 2 seconds). One method to detect this variation is to filter and perform FFT calculations on a series of consecutive cyc10 values and analyze the resulting spectrum. If the cyc10 value sequence changes periodically, then one frequency point in the FFT spectrum will have greater energy than the others. Regarding the selection of the modulation frequency, the following analysis is needed: the cyc10 duration (10 cycles) is approximately 0.2 seconds. Therefore, the period of the cyc10 value sequence must be greater than 0.2 seconds and the frequency must be less than 5Hz. According to the Nyquist sampling theorem, the sampling frequency must be greater than twice the signal frequency; otherwise, spectral aliasing will occur. The cyc10 value sequence is equivalent to sampling the changing envelope of the modulating wave, and the sampling rate is approximately 5Hz. Therefore, the modulation frequency must be less than 2.5Hz to satisfy the relationship between the cyc10 value variation frequency and the sampling rate for effective FFT analysis. 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 by 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: Acquire signal parameter information of a preconfigured three-phase voltage signal.

[0055] S420, construct a fundamental signal based on 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 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 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, a total of 128 10 cycles are included, each cycle has 256 sampling values, each sampling value corresponds to a corresponding time value, and the sampling interval is 0.000078125 seconds. Then, there are a total of 327,680 sampling values in 128 10 cycles.

[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 based on 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: Determine a modulation signal corresponding to the current modulation frequency, and construct a fundamental modulation signal using the modulation signal and the fundamental 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. For example, 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; the 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), where 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 the 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 the amplitude of a frequency point by the sum of the amplitudes of two adjacent frequency points on the left and right.

[0062] In this embodiment, a 10-cycle effective value sequence corresponding to all sampled values within each 10-cycle measurement period is determined using a fundamental modulation signal. It can be understood that the fundamental measurement period is 10 cycles, and the voltage signal is uniformly sampled within the 10 grid cycles. A 10-cycle effective value sequence is calculated using all sampled values within each 10-cycle measurement period. FFT analysis is performed on the 10-cycle effective value sequence, converting the time domain signal to the frequency domain to obtain a 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 a first enhancement value, and the current modulation frequency corresponding to the first enhancement value is recorded. For example, 256 samples are taken per cycle, resulting in a total of 2560 values. From these 2560 sampled values, a 10-cycle effective value sequence, harmonic values, and interharmonic values can be inferred, and the sampling start time and sequence number are recorded. Specifically, the 10-cycle effective value sequence, harmonic values, and interharmonic values can be calculated by squaring each value, averaging the squared values, and then taking the square root of the average. 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 corresponding to two frequency points adjacent to the frequency point with the maximum power spectral density; calculating the cumulative sum of the first amplitude and the second amplitude; and using the ratio of the amplitude of the frequency point with the maximum power spectral density to the cumulative sum as the enhancement value. Specifically, the ratio is calculated by dividing the amplitude of one frequency point by the sum of the amplitudes of the two adjacent frequency points on its 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 the amplitude of a frequency point by the sum of the amplitudes of two adjacent frequency points on the left and right.

[0066] In this embodiment, the abnormal 10-cycle RMS value sequence can be obtained by simulating a sampling gap, which can be understood as being obtained by intentionally omitting or modifying one sample value in the 10-cycle sampling value sequence. In this embodiment, the abnormal 10-cycle RMS value sequence is calculated by modifying or intentionally omitting the first sample value in the 10-cycle sampling value sequence, and an FFT analysis is performed on the abnormal 10-cycle RMS value sequence to obtain a corresponding second spectrum array. The frequency point with the largest power spectral density is selected from the second spectrum array for energy enhancement to obtain a 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. Due to the presence of 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 the multiple candidate enhancement values subsequently.

[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 obtain a candidate enhancement value list including at least two candidate enhancement values. Select the maximum candidate enhancement value from the candidate enhancement value list, and use the modulation frequency corresponding to the maximum candidate enhancement value 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 frequencies and used as the current modulation frequency. The process returns to the step of determining the modulation signal corresponding to the current modulation frequency to calculate the next candidate enhancement value. This process continues until all preset modulation frequencies are traversed, resulting in a candidate enhancement value list including at least two candidate enhancement values. 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. This can be understood as selecting the maximum candidate enhancement value Q from the candidate enhancement value list, and using the modulation frequency corresponding to the maximum Q value as the optimal modulation frequency. In this embodiment, the optimal modulation frequency is the frequency with the highest sensitivity and is particularly sensitive to abnormal variations in the cyc10 value. It should be noted that selecting the maximum candidate enhancement value from the candidate enhancement value list can include sorting all candidate enhancement values included in the candidate enhancement value list according to their magnitude to obtain a sorted result, and selecting the candidate enhancement value with the highest ranking from the sorted result as the maximum candidate enhancement value. This can be understood as sorting each candidate enhancement value from largest to smallest or from smallest to largest to obtain the maximum candidate enhancement value.

[0072] For example, 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, 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 inverse of the duration of the FFT input data, i.e., the resolution of the spectrum generated by the FFT. To better understand the 62 Q values of the 128 cyc10 value sequence when modulating the fundamental wave with the optimal modulation frequency, Figure 6 The Q value of a voltage RMS sequence provided by an embodiment of the present invention is: Since 128 is an integer power of 2, it is convenient for FFT calculation, with a duration of approximately 25.6 seconds and a spectrum resolution of approximately (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, the fundamental wave amplitude V_b, the fundamental wave frequency F_b, the duration of 128×10 cycles, the modulation amplitude A_m = 20%, and the 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. 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. Add Fn to F_m and determine whether F_m is greater than Fn × 62. If so, execute a9; otherwise, return to execute a3.

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

[0083] S480: Construct a fundamental wave modulation signal, a harmonic modulation signal, and an interharmonic modulation signal using an optimal modulation frequency.

[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. For example, the fundamental signal is S_b = V_b × sin(2 × pi × F_b × t0_660); where t0_660 represents the sampling time point sequence, S_m = 1.0 + A_m × sin(2 × pi × F_m × t0_660); the fundamental modulation signal is expressed as S_bm = S_b × S_m; the harmonic modulation signal is expressed as S_hm = S_b + V_h × sin(2 × pi × F_h × t0_660). × S_m; and the interharmonic modulation signal is expressed as S_im = S_b + V_i × sin(2 × pi × F_i × t0_660). × S_m.

[0085] S490: Count 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 can 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, etc.

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

[0088] S4100. Obtain a 10-cycle effective value sequence through the fundamental wave modulation signal and the number of sampling values per cycle within a 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.

[0089] The 10-cycle effective value sequence includes effective values and time stamps corresponding to the effective values, and the 150-cycle effective value sequence includes effective values and time stamps 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 stamps corresponding to the harmonic values, and the 150-cycle harmonic value sequence includes harmonic values and time stamps 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. The 150-cycle harmonic value sequence Sec3_hm corresponding to the multiple 150 cycles is obtained by using the 10-cycle harmonic value sequence and the number of 150-cycle values included in every 10 minutes.

[0094] S4120. Obtain a 10-cycle interharmonic value sequence by summing the interharmonic modulation signal and the number of interharmonic values per cycle within a preset time interval, and aggregate 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 from the 10-cycle interharmonic values corresponding to the multiple 10 cycles included in 10 minutes. The interharmonic value sequence S_sec3_im is obtained by forming an interharmonic value sequence from 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. Perform FFT analysis on the 10-cycle harmonic value sequence to obtain a third spectrum array, calculate 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.

[0098] In this embodiment, FFT analysis is performed on the 10-cycle harmonic value sequence to obtain a third spectrum array, and the third enhancement value corresponding to each frequency point in the third spectrum array is calculated. The maximum 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, 256 samples per cycle, and 2560 sampling values are obtained 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 the third spectrum array, calculate the third enhancement value corresponding to each frequency point in the third spectrum array, and select the maximum 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 spectrum 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 spectrum 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 spectrum 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 of each frequency point, i.e., the amplitude;

[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 in 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. Perform FFT analysis on the 10-cycle interharmonic value sequence to obtain a corresponding fourth spectrum array, calculate the fourth enhancement value corresponding to each frequency point in the fourth spectrum array, and select 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 a fourth enhancement value corresponding to each frequency point in the fourth spectrum array is calculated. The largest 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 taken per cycle, and 2560 sampling values are taken 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 to perform FFT analysis on the 10-cycle interharmonic value sequence to obtain the corresponding fourth spectrum array, calculate the fourth enhancement value corresponding to each frequency point in the fourth spectrum array, select the largest enhancement value from the fourth enhancement value as the enhancement value of the 10-cycle interharmonic value sequence, specifically, determine the amplitude corresponding to the frequency point with the largest power spectrum density in the fourth spectrum array, and determine the amplitudes corresponding to the two frequency points adjacent to the frequency point with the largest power spectrum density in the fourth 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 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, 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 number of continuous value sequences in sequence, and Fourier transform FFT analysis is performed on each continuous value sequence to obtain the corresponding fifth spectrum arrays, and the fifth enhancement value corresponding to each frequency point in each fifth spectrum array is 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 = 50 Hz, the duration of 10 cycles is 0.2 seconds and the duration of sec3 is 3 seconds. Therefore, 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, 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, respectively; when the ratio is greater than a preset threshold, it is determined that the sampling value overlap can be detected.

[0111] S4160. Calculate the number of 10-cycle value sequences from the first preset time to the second preset time, record the number of 10-cycle value sequences as N, and use 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-th 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-th value of Cyc10_bm is Cyc10_bmZ, because the sampling value sequence before and after the 10-minute moment is continuous and equally spaced, the time of the first sampling value used to calculate the value is before the 10-minute moment, and the time of the last sampling value used to calculate the value is after the 10-minute moment. The fundamental modulation signal S_bm is constructed from the modulation signal and the fundamental signal. Generating Cyc10_bm from S_bm involves calculating a cyc10 value sequence from S_bm and performing 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 in 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. 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. This preset number can be customized as needed. For example, to better obtain the 150-cycle overlap 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 between the first preset time and the second preset time, every 15 values are divided into a group for calculating the 150-cycle value. If 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 overlap value is aggregated from this last group of 10-cycle values. For example, the first part is selected from the last cyc10 value of the current 10 minutes, and 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, and the number is ceil(Num_cyc10_10min / 15)-Num_cyc10_10min. These two parts, totaling 15 cyc10 values, are combined in order to form a sequence. 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 MATLAB system function used to round up to an integer, and floor is used to round down to an integer.

[0117] S4180. Select a third number of 10-cycle values from the 10-cycle value sequence within 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 spectrum array, calculate the sixth enhancement value corresponding to each frequency point in the sixth spectrum array, and select the largest enhancement value from the sixth enhancement values 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 the 10 cycle value sequence within the first preset time to the second preset time, and a fourth number of 10 cycle values are selected from the 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 the target 10 cycle value sequence is subjected to FFT analysis to obtain the corresponding sixth spectrum array, and the sixth enhancement value corresponding to each frequency point in the sixth spectrum array is calculated, and the largest enhancement value is selected from the sixth enhancement value as the enhancement value of the 10-cycle overlap 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 the two frequency points adjacent to the frequency point with the largest power spectrum density in the sixth 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. For example, for a sequence containing 128 Cyc10 values, the last 127 Cyc10 values are selected from the current 10-minute Cyc10 values (i.e., the first 127 values are the last at 0:10), and the first Cyc10 value is selected from the next 10-minute Cyc10 values (the last Cyc10 value is the first at 0:20). These values are sequentially combined into a sequence of 128 values, which is then input into the function Q_rms_max. The resulting value is Q_Cyc10_bmZ. The calculation process for Q_Cyc10_hmZ and Q_Cyc10_imZ is similar. In this embodiment, the function Q_rms_max performs FFT analysis on the sequence to calculate the amplitude and 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 a corresponding 150-cycle value, form a target 150-cycle value sequence from each 150-cycle value, 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 values 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. FFT analysis is performed on the target 150-cycle value sequence to obtain the corresponding seventh spectrum array. Seventh enhancement values corresponding to each frequency point in the seventh spectrum array are calculated, and the largest enhancement value among the seventh enhancement values is selected as the enhancement value for the 150-cycle overlap value. Specifically, the amplitude corresponding to the frequency point with the highest power spectral density in the seventh spectrum array is determined, as well as the amplitudes corresponding to two frequency points adjacent to the frequency point with the highest power spectral density in the seventh spectrum array. 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 highest power spectral density to the cumulative sum is used as the corresponding enhancement value. It can be understood that the calculation method for Q_Sec3_bmZ is to select the last Num_Sec3_Q values from the 150-cycle values of the current 10 minutes and input them into the function Q_rms_max to calculate Q_Sec3_bmZ. The calculation process for 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. If the comparison shows equality, determine that the preliminary test 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. If the comparison shows equality, the preliminary verification result is determined to have passed. 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 whether the number of Sec3 values is equal to Num_Sec3_10min. If they are not equal, such an 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 is 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, is calculated. If the error does not exceed a preset error threshold, the preliminary verification result is determined to have 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%) 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. Calculate the relative error between each Sec3 value collected from 0:10 to 0:20 and the 150-cycle sequence of the standard characteristic value sequence. The absolute value of the error should not exceed (0.5% × 60%). The number of comparisons is Num_Sec3_10min. If any value exceeds the standard, report the number of the error value and terminate the test.

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

[0127] In this embodiment, after all basic tests are passed, the calculation of Cyc10 values is performed to determine whether 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 at 0:10 collected from the EUT, and to perform Q value analysis and comparison on the Sec3 value sequence starting at 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 the distribution substation area is determined based on a preliminary calibration result, including: determining a first calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in the distribution substation area 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; determining a second calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in the distribution substation area 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; determining a third calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in the distribution substation area 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 determining a fourth calibration result of an actual calibration signal measurement result output by the power quality monitoring equipment in the distribution substation area 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 the enhanced value of a 10-cycle value sequence in a standard characteristic value sequence and the 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, 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, according to the corresponding time scales, 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 are respectively compared with the enhanced value of the standard 10-cycle value sequence. The enhanced values of the 10-cycle effective value sequence, the enhanced values of the 10-cycle harmonic value sequence, and the enhanced values of the 10-cycle interharmonic value sequence are compared; if they are within the preset error threshold range, the test is determined to be normal, and the time scale of the 10-cycle value sequence corresponding to the last 10 cycles is determined to be greater than or equal to the second preset time. If it is greater than or equal to the second preset time, the 10-cycle value sequence corresponding to each 10 cycles within the first preset time is determined to be 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. The step of returning to the determination 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 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. 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 a 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 of the current abnormal sequence number, and re-verifying the actual 10-cycle value sequence corresponding to the 10-cycle 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 10-cycle value sequence corresponding to the 10-cycle of the current abnormal sequence number, until the verification of the 10-cycles of 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 corrected current abnormal sequence number is re-calibrated, including: calculating the enhanced value of the actual 10-cycle value sequence corresponding to the 10 cycles of the corrected current abnormal sequence number as the current enhanced value; judging whether the error between the current enhanced value and the enhanced 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 corrected current abnormal sequence number.

[0132] In this embodiment, a method for correcting the actual 10-cycle value sequence corresponding to the 10 cycles of the current abnormal sequence number using a 10-cycle value sequence in a standard characteristic value sequence with the same time scale from the first preset time to the second preset time, and a preset correction factor includes: finding the 10-cycle value sequence in the standard characteristic value sequence with the same time scale, 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 this embodiment, the method for determining the third verification result of the actual verification signal output by the power quality monitoring equipment in the distribution station area based on 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 method for determining the above-mentioned first verification result, and this embodiment will not be described in detail here. Similarly, the method for determining the fourth verification result of the actual verification signal output by the power quality monitoring equipment in the distribution station area based on 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 method for 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 This is a flow chart for detecting abnormal 10-cycle value measurements provided by 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 also similar, and the correction factor is (V_b / Sec3_C); among them, V_b represents the fundamental wave amplitude; Sec3_A represents the identifier corresponding to Cyc10_bm; Sec3_B represents the identifier corresponding to Cyc10_hm, and Sec3_C represents the identifier corresponding to Cyc10_im. For example 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. Check whether the time stamp of number (no+len+1) is 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 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 so, execute b11; otherwise, 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 only performed if the final Cyc10 value of min10 has been verified to be qualified, in order to detect whether the sampled values are correctly overlapped. Specifically, the Cyc10 valid value sequence collected from the EUT is used, and Q_Cyc10_bmZ is calculated according to its time stamp using 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 methods for verifying Q_Cyc10_hmZ and Q_Cyc10_imZ are 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, the test is determined to be normal, and the time scale of the 150-cycle value sequence corresponding to the last 150 cycles is determined to be greater than or equal to the second preset time. If so, the 150-cycle value sequence corresponding to each 150 cycles within the first preset time is determined to be 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 step of determining whether the error is within the preset error threshold range is returned; if not, the actual 150-cycle value sequence corresponding to each of the first 150 cycles to the last 150 cycles is determined to have a test abnormality, and the test result is determined 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. 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 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 of the current abnormal sequence number, and re-verifying the actual 150-cycle value sequence corresponding to the 150-cycle value 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 of the current abnormal sequence number, until the verification of the 150-cycle value 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 values provided in 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 for correcting Sec3 values 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 at this number is abnormal and replace it with the 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 anomalies is similar, with the correction factor being (V_b / Sec3_B). The verification process for Sec3_im anomalies is similar, with the correction factor being (V_b / Sec3_C). Where 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. Check whether the time stamp of number (no+len+1) is 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 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 so, execute c11; otherwise, 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's important to note that this step is designed to verify that Cyc10 values are correctly overlapped. This step is only performed if the final Sec3 value of min10 has passed verification. Specifically, using the sequence of valid Sec3 values collected from the EUT and their time stamps, Q_Sec3_bmZ is calculated according to the aforementioned steps. This value should be no greater than 1.5 times the ideal value and no less than 0.5 times the ideal value; otherwise, an abnormality is reported. The methods for verifying Q_Sec3_hmZ and Q_Sec3_imZ are similar.

[0167] The above technical solution in this embodiment is achieved by designing a calculation method for the 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 will change. Three voltage signals are designed for verification through the optimal modulation frequency, including a fundamental modulation signal, a harmonic modulation signal, and an interharmonic modulation signal. The multiple characteristic values of these three modulation signals are calculated to be a standard characteristic value sequence. 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 a 150-cycle value, and the detection of overlapping implementation anomalies at 10 minutes.

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

[0169] like Figure 9 As shown, the system includes: a programmable power source 910, an EUT 920, a clock source 930 and a host computer 940;

[0170] The programmable power source 910 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;

[0171] The EUT 920 is configured 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 respectively correspond to corresponding signal parameter information;

[0172] The host computer 940 is configured to execute the verification method for power quality monitoring equipment in a 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 EUT 920; the programmable power source 910 and the EUT 920 communicate with the host computer 940 via Ethernet respectively; the clock source 930 is connected to the programmable power source 910 and the EUT 920 respectively; the programmable power source 910 is connected to the host computer 940 and the power quality monitoring device EUT 920; the EUT 920 is connected to the host computer 940.

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

[0176] In this embodiment, the PPS is a programmable power source that receives configuration commands from a PC and outputs a test signal to the EUT. This power source, model NETWAVE20, provides a continuous, stable, and accurate three-phase voltage signal. The output signal waveform is programmable, meaning its output frequency, amplitude, and phase can be programmed, allowing it to output a predetermined waveform at specific times and time periods.

[0177] The EUT is the equipment under test (EUT), a power quality monitoring device that receives, monitors, and measures calibration signals, providing measurement data to a personal computer (PC). The SPT is a clock source that receives satellite signals and periodically outputs a stable, accurate time signal. This information is transmitted to the PPS and EUT via an RS485 communication line. This time information is encoded in IRGB format and output once per second, synchronizing the time values of multiple devices once per second. This is a commonly used device that ensures consistent timing between the PPS and the EUT. The EUT often uses a high-frequency clock crystal as its internal timing source, achieving a timing accuracy of 10ppm, meaning an error of less than 10 microseconds within one second. The host computer is a computer and the core of the testing process. It issues configuration commands to the PPS and EUT, collects EUT measurement data, and analyzes and presents calibration conclusions. Specifically, it edits the parameters of the PPS calibration voltage signal (frequency, amplitude, phase, harmonics, interharmonics, modulation frequency, modulation amplitude, etc.), controls the time when the PPS outputs the calibration signal, collects 10-cycle data and 150-cycle data of the EUT output, analyzes whether it is synchronous sampling of the power frequency, analyzes 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 provides a calibration report.

[0178] To better understand the calibration process, this embodiment uses a standard eigenvalue group with a fundamental frequency of 49.46 Hz and an actual detection item group with a fundamental frequency of 50.58 Hz as examples. The configuration parameters for the eigenvalue group with a fundamental frequency of 49.46 Hz are as follows: 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 = 49.46 Hz, F_h = N_har × F_b, and F_i = N_ihar × F_b. After execution, the following detection items, comparison values, and eigenvalues are obtained: the number of cyc10 values within 10 minutes (Num_cyc10_10min = 2968, Num_sec3_10min = 198); and the length of the sequence Q value for the sec3 value sequence (Num_sec3_Q = 196).

[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, is 3055; the number of sec3 values, Num_sec3_10min, is 203. The length of the sec3 value sequence Q, Num_sec3_Q, is calculated to be 200.

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

[0191]

[0192] Table 6. Q values for detecting anomalies in a 10-cycle, 150-value sequence

[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 the standard characteristic values are calculated. Figure 10 Connect each device and power on. Set the above parameters as the parameters of the PPS output voltage signal. Also, starting at 0:00:00, each phase outputs the unmodulated fundamental signal S_b. Starting at 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 a modulated signal. Set the SPT time value to 0:00:00. Synchronize the PPS clock with the SPT, and synchronize the EUT clock with the SPT. Turn on the PPS voltage signal output switch. Start the PC calibration software and start collecting the cyc10 and sec3 values measured by the EUT. Store them 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. Phase A is labeled Sec3_A, Phase B is labeled Sec3_B, and Phase C is labeled Sec3_C. These values are the EUT's measured values of the unmodulated PPS output signal. They are used to calculate the error between the EUT's measured value and the PPS output value, and are used to correct the EUT's measured value and aggregate value during subsequent verification items. Under normal circumstances, these relative error values should be less than plus or minus (0.5% × 60%). If they exceed this, an abnormality is reported and verification is stopped. For example, if the PPS output amplitude is set to 100V and the EUT measures 100.3V, it is qualified, but there is a 0.3% error. If 100.3V is corrected by 0.3%, a value very close to 100V can be obtained.

[0200] Statistics are collected from 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) for a certain min10 (the tens digit of the time stamp minute value is the same for each cyc10 sampling start time. For example, when the fundamental frequency is 50Hz, the first cyc10 is 0:10:00, the second is 0:10:02, the third is 0:10:06, the 300th is 0:10:59.8, the 301st is 0:11:00, the 302nd is 0:11:0.2, and the 3000th is 0:19:59.8). These two values can be calculated from the sampling interval (T_s) and the time length. The number of cyc10s and sec3s between 0:10 and 0:20 is counted. 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 between 0:10 and 0:20 and the standard characteristic value. The absolute value of the error should not exceed (0.5% x 60%) to ensure that the error does not exceed 0.5% during batch use of the device. During verification, the limit is 60% of the agreed value. The number of comparisons is Num_cyc10_10min. If any value exceeds the standard, the error value number is reported and verification is terminated. The Cyc10 value of phase A is compared to Cyc10_bm, the Cyc10 value of phase B is compared to Cyc10_hm, and the Cyc10 value of phase C is compared to 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 should not exceed (0.5% x 60%). The number of comparisons is Num_sec3_10min. If any value exceeds the standard, the error value number is reported and the test is terminated. Phase A is compared to Sec3_bm, Phase B is compared to Sec3_hm, and Phase C is compared to Sec3_im. Note that the last sec3 value from 0:10 to 0:20 is Sec3_bmZ, Sec3_hmZ, and Sec3_imZ.

[0203] After passing all basic tests, the calculation of the Cyc10 values is checked for omissions or overlaps. This additional step is performed after all the above tests have passed to identify if the EUT uses only a few Cyc10 values instead of 15, or if there are any duplicate Cyc10 values, when performing Sec3 aggregation. The specific verification method has been described in the previous steps and will not be explained separately in this embodiment.

[0204] In one embodiment, Figure 10 A schematic diagram of overlapping verification of 10-cycle and 150-cycle power quality parameters provided by an embodiment of the present invention. Figure 10 As shown, the basic measurement period is 10 cycles. The voltage signal is evenly sampled within 10 grid cycles, for example, 256 times per cycle, for a total of 2560 values. The voltage RMS, harmonics, and interharmonics are calculated from these 2560 samples, and the sampling start time and sequence number are recorded. These five parameters are used to identify the power quality characteristics of the 10-cycle voltage signal. The 150-cycle RMS aggregation algorithm aggregates 15 consecutive, non-overlapping 10-cycle RMS values. The harmonics and interharmonics values are also calculated using this method, and the sequence number and start time of the first 10-cycle are recorded. These parameters are used to identify the power quality characteristics of the 150-cycle voltage signal. Illustratively, this embodiment is described by taking k=Num_cyc10_10min and n=Num_sec3_10min as an example, wherein k=Num_cyc10_10min represents the number of 10-cycle value sequences within the current 10 minutes, and n=Num_sec3_10min represents the number of 150-cycle value sequences within the current 10 minutes.

[0205] like Figure 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 from 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 In Overlap 1, the two cycles 10 minutes before and after will overlap for a portion of their time period, and the signal samples within that overlapped time period will be used twice. The two cycles 3 before and after 10 minutes will also overlap. For example, in Overlap 2, the last two cycles 10 minutes before and the first two cycles 10 minutes after completely overlap. Verifying these two types of overlap is also a key point in the verification process. The verification method in this embodiment allows for verification of overlap.

[0206] right Figure 10 Overlap 1 in the test: from Figure 10 As can be seen, at each min10 moment, the first cyc10 of the current 10-minute period overlaps with the last cyc10 of the previous 10-minute period, but the overlap duration is less than cyc10. The sampled values within this period are reused. This step is designed to verify that the sampled values are correctly overlapped. It is only performed if the final cyc10 value of the min10 has passed verification. Specifically, the sequence of valid cyc10 values collected from the EUT is used, based on its time stamp, to calculate Q_cyc10_bmZ according to the verification method described above. 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 verification methods for Q_cyc10_hmZ and Q_cyc10_imZ are similar.

[0207] right Figure 10 Overlap 2 in the test: from Figure 10As can be seen, one or more cyc10 values starting at each min10 moment may be reused: aggregated with the last sec3 value of the previous 10 minutes, and then aggregated with the first sec3 value of the current 10 minutes. This step is designed to detect whether cyc10 values are correctly overlapped. This step is only performed if the last sec3 value of the min10 has passed the verification. Specifically, using the sequence of valid sec3 values collected from the EUT and its time stamp, Q_sec3_bmZ is calculated according to the verification method described above. 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 verification methods for Q_sec3_hmZ and Q_sec3_imZ are similar.

[0208] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. This is not limited herein.

[0209] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A method for verifying power quality monitoring equipment in a distribution 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, based on the optimal modulation frequency, 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; 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; Determining a verification result of an actual verification signal measurement result output by the power quality monitoring equipment in the distribution station area based on the standard characteristic value sequence and the actual characteristic value sequence, and generating a verification report based on the verification result; The determining of the optimal modulation frequency based on the signal parameter information includes: Constructing a fundamental wave signal according to the number of sampling values within each of the 10-cycle measurement periods and the time value, fundamental wave amplitude, and fundamental wave frequency of each sampling value, and randomly selecting a modulation frequency from 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; Determining, based on the fundamental wave modulation signal, a 10-cycle effective value sequence corresponding to all sampling values within each of the 10-cycle measurement periods, performing Fourier transform (FFT) analysis on the 10-cycle effective value sequence to obtain a corresponding first spectrum array, and selecting a frequency point with the largest power spectrum density from the first spectrum array for energy enhancement to obtain a first enhancement value; Modifying the first 10-cycle RMS values in the 10-cycle RMS value sequence to obtain an abnormal 10-cycle RMS value sequence, performing FFT analysis on the abnormal 10-cycle RMS value sequence to obtain a corresponding second spectrum array, and selecting a frequency point with a maximum power spectrum density 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 obtain a candidate enhancement value list including at least two candidate enhancement values, select the maximum candidate enhancement value from the candidate enhancement value list, and use the modulation frequency corresponding to the maximum candidate enhancement value as the optimal modulation frequency.

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 1, 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 with 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.

4. The method according to claim 1, wherein 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; The candidate enhancement value with the largest ranking is selected from the ranking results as the maximum candidate enhancement value.

5. The method according to claim 1, wherein The standard characteristic value sequence includes standard characteristic values, and corresponding test values and time scales corresponding to each standard characteristic value; 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 cycle value sequence, enhanced value of the 150 cycle value sequence, 150 cycle overlapping value, enhanced value of the 150 cycle overlapping value.

6. The method according to claim 5, 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.

7. The method according to claim 5, 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 value of the 150-cycle value sequence includes: the enhanced value of the 150-cycle effective value sequence, the enhanced value of the 150-cycle harmonic value sequence, and the enhanced value 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.

8. The method according to any one of claims 6 or 7, characterized in that: 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, including: Constructing a fundamental wave modulation signal, a harmonic modulation signal and an interharmonic modulation signal by using the optimal modulation frequency; Counting the number of 10-cycle waves, the number of 150-cycle waves, the number of 10-cycle value sequences corresponding to each 10-cycle wave, and the number of 150-cycle value sequences corresponding to each 150-cycle wave within the preset time interval; Obtain a 10-cycle effective value sequence by using 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 by using 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.

9. The method according to claim 6, 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 stamps corresponding to the interharmonic values, and the 150-cycle interharmonic value sequence includes interharmonic values and time stamps corresponding to the interharmonic values.

10. The method according to claim 8, characterized in that 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, 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 number of continuous value sequences, and FFT analysis is performed on each of the continuous value sequences to obtain the corresponding fifth spectrum arrays. 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.

11. The method according to claim 8, characterized in that The generating, based on the optimal modulation frequency, standard characteristic value sequences corresponding to the 10-cycle value sequence and the 150-cycle value sequence for power quality verification within a preset time interval respectively includes: Calculate the number of 10-cycle value sequences between the first preset time and 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.

12. The method according to claim 11, characterized in that The generating, based on the optimal modulation frequency, standard characteristic value sequences corresponding to the 10-cycle value sequence and the 150-cycle value sequence for power quality verification within a preset time interval respectively includes: selecting a third number of 10-cycle values from the 10-cycle value sequence between the first preset time and 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 a 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. The largest enhancement value is selected from the seventh enhancement values as the enhancement value of the 150-cycle overlapping value.

13. The method according to claim 10, characterized in that The calculation method of the third enhancement value includes: Determine a third amplitude and a fourth amplitude 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 maximum power spectrum density to the accumulated sum is used as the third enhancement value.

14. The method according to claim 10, characterized in that The calculation method of the fourth enhancement value includes: Determine a fifth amplitude and a sixth amplitude corresponding to two frequency points adjacent to the frequency point with the maximum power spectrum density in the fourth 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 maximum power spectrum density to the accumulated sum is used as the fourth enhancement value.

15. The method according to claim 10, characterized in that The calculation method of the fifth enhancement value includes: Determine a seventh amplitude and an eighth amplitude 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 maximum power spectrum density to the accumulated sum is used as the fifth enhancement value.

16. The method according to claim 12, characterized in that The calculation method of the sixth enhancement value includes: Determine a ninth amplitude and a tenth amplitude corresponding to two frequency points adjacent to the frequency point with the maximum 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 maximum power spectrum density to the accumulated sum is used as the sixth enhancement value.

17. The method according to claim 12, wherein: The calculation method of the seventh enhancement value includes: Determine an eleventh amplitude and a twelfth amplitude 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 maximum power spectrum density to the accumulated sum is used as the seventh enhancement value.

18. The method according to claim 1, wherein The determining of the verification result of the actual verification signal output by the power quality monitoring equipment in the distribution station area based on the standard characteristic value sequence and the actual characteristic value sequence includes: Comparing 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 determining that the preliminary test result passes if 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, 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 within a preset time interval. If the error does not exceed a preset error threshold, determine that the preliminary test result is passed. 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.

19. The method according to claim 18, characterized in that The determining, based on the preliminary verification result, of a target verification result of an actual verification signal output by the power quality monitoring equipment in the distribution station area, comprises: Determining a first verification result of an actual verification signal output by the power quality monitoring device in the distribution station area according to an enhanced value of a 10-cycle value sequence in the standard characteristic value sequence and an enhanced value of an actual 10-cycle value sequence in the actual characteristic value sequence; Determining 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 in the actual characteristic value sequence; Determining 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.

20. The method according to claim 19, characterized in that The determining of the 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 includes: Counting 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, determining whether the errors between the enhancement values of the actual 10-cycle value sequence corresponding to the first 10 cycles to the last 10 cycles and the enhancement values of the 10-cycle value sequence in the standard feature value sequence are within a preset error threshold range; If it is 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 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 process returns to the step of determining 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.

21. The method according to claim 20, characterized in that The determining of 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, selecting one of the abnormal sequence numbers as the current abnormal sequence number, using a 10-cycle value sequence in a standard characteristic value sequence with the same time scale from the first preset time to the second preset time, and a 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-calibrating 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 number, use 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.

22. The method according to claim 21, 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 of the corrected current abnormal sequence number as the current enhanced value; Determine whether an error between the current enhancement value and the enhancement value of a 10-cycle value sequence with the same time scale in the standard characteristic value sequence is within a preset error threshold range; If so, determine whether 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.

23. The method according to claim 19, wherein The second verification result of the actual verification signal output by the power quality monitoring device in the distribution station area is determined based on 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, including: 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 so, 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. The process returns to the step of determining whether the error is within the preset error threshold range. 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.

24. The method according to claim 23, wherein The determining of 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 one abnormal sequence number is selected as the current abnormal sequence number. 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 a preset second correction factor. The actual 150-cycle value sequence corresponding to the 150 cycles of the current abnormal sequence number after correction is re-calibrated. Select the next abnormal sequence number from the abnormal sequence number, use 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 obtain at least two actual 150-cycle value sequences with verification abnormalities.

25. A calibration system for power quality monitoring equipment in a distribution station area, characterized in that: The system includes: a program-controlled power source, a power quality monitoring device EUT, a clock source and a host computer; Wherein, the programmable 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 configured to receive a three-phase voltage signal and obtain an actual verification signal from a signal source, and transmit 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 respectively correspond to corresponding signal parameter information; 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 24; The clock source 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 is synchronized.

26. The system according to claim 25, characterized in that The clock source outputs a time signal via 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.

27. The system according to claim 25, wherein: The host computer includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed 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 of the distribution station area according to any one of claims 1-24.

28. 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 verification method of the power quality monitoring equipment of the distribution station area according to any one of claims 1 to 24 when executed.

29. A computer program product, characterized in that The computer program product includes 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 to 24.

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