Transient signal traceable measurement and evaluation system and method in power distribution scene

Abstract

The invention belongs to the technical field of digital detection of power distribution automation equipment, and particularly relates to a transient signal traceable measurement and evaluation system and method in a power distribution scene, and the system comprises a power distribution automation terminal detection platform power source which is used for simulating a transient voltage / current signal and transmitting the transient voltage / current signal to a voltage / current processing unit; the voltage / current processing unit is used for processing the transient voltage / current signal to obtain a test signal and sending the test signal to the oscilloscope and the data processing unit; the oscilloscope is used for generating a waveform of the test signal after receiving the test signal, obtaining a test waveform and sending the test waveform to the data processing unit; and the data processing unit is used for carrying out quality analysis on the test signal according to the test waveform. According to the technical scheme provided by the invention, accurate measurement and quality evaluation of the power source analog output transient signal are realized by utilizing traceable instrument equipment.

Description

Technical Field

[0001] This invention belongs to the field of digital detection technology for power distribution automation equipment, specifically relating to a traceable measurement and evaluation system and method for transient signals in power distribution scenarios. Background Technology

[0002] In the field of digital testing of power distribution automation equipment, one of the core tasks is to verify the fault identification and handling functions of power distribution automation equipment by inverting the output of short-circuit and ground fault signals through power source. Since fault signals are usually transient, the measurement and quality assessment of transient signals are indispensable tasks for digital testing.

[0003] For transient signal measurement and quality assessment techniques, most related technologies involve measuring with self-made hardware circuits, such as using FPGAs as controllers and designing peripheral circuits to measure transient signals. However, these hardware circuits contain many untraceable components, which cannot accurately reproduce transient signals, making them highly detrimental to transient signal detection and identification. Summary of the Invention

[0004] To overcome the problems existing in the above-mentioned related technologies, this application provides a traceable measurement and evaluation system and method for transient signals in power distribution scenarios.

[0005] According to a first aspect of the embodiments of this application, a transient signal traceability measurement and evaluation system in a power distribution scenario is provided, comprising: a power source of a power distribution automation terminal detection platform, a voltage / current processing unit, an oscilloscope, and a data processing unit connected in sequence, wherein the voltage / current processing unit is connected to the data processing unit;

[0006] The power source of the power distribution automation terminal detection platform is used to simulate transient voltage / current signals and send the transient voltage / current signals to the voltage / current processing unit;

[0007] The voltage / current processing unit is used to process the transient voltage / current signal to obtain a test signal, and send the test signal to the oscilloscope and the data processing unit;

[0008] The oscilloscope is used to generate the waveform of the test signal after receiving the test signal, obtain the test waveform, and send the test waveform to the data processing unit.

[0009] The data processing unit is used to perform quality analysis on the test signal based on the test waveform.

[0010] Preferably, the voltage / current processing unit includes:

[0011] A high-voltage probe, connected to the power source of the power distribution automation terminal testing platform and the oscilloscope respectively, is used to compress the transient voltage signal to obtain the test signal.

[0012] Preferably, the voltage / current processing unit further includes:

[0013] The current transformers connected to the power source of the power distribution automation terminal detection platform and the oscilloscope are used to compress the transient current signal to obtain the test signal.

[0014] Preferably, the data processing unit includes:

[0015] The alignment subunit is used to align the test waveform with a preset standard waveform to obtain the aligned test waveform;

[0016] The trimming subunit is used to trim the sensitive bands in the standard waveform and the sensitive bands in the aligned test waveform;

[0017] The analysis subunit is used to perform quality analysis on the test signal corresponding to the sensitive band in the aligned test waveform and the standard signal corresponding to the sensitive band in the standard waveform using the sensitive band in the aligned test waveform and the sensitive band in the standard waveform.

[0018] Preferably, the alignment subunit includes:

[0019] The first alignment module is used to align the test waveform forward with the standard waveform;

[0020] The second alignment module is used to delete invalid information at the rear end of the test waveform after the test waveform and the standard waveform are aligned forward, so that the test waveform and the standard waveform are aligned backward.

[0021] Preferably, the first alignment module is specifically used for:

[0022] Identify the critical points where faults occur in the test waveform and the standard waveform;

[0023] Subtract the number of points in the standard waveform corresponding to the key point from the number of points in the test waveform corresponding to the key point to obtain the first offset point number.

[0024] The test waveform is shifted forward by a first offset point number so that the test waveform is aligned forward with the standard waveform.

[0025] Preferably, the sensitive bands in the standard waveform include: the bands corresponding to the first n1 periods of the fault time in the standard waveform and the bands corresponding to the last n2 periods of the fault time in the standard waveform.

[0026] The sensitive bands in the aligned test waveform include: the bands corresponding to the first n1 periods of the fault time in the test waveform and the bands corresponding to the last n2 periods of the fault time in the test waveform; wherein, 0 <n1<n2。

[0027] Preferably, the analysis subunit includes:

[0028] The transformation module is used to convert the test signal corresponding to the sensitive band in the aligned test waveform from a real signal to a complex signal using the Hilbert transform method, to obtain the transformed test signal; and to convert the standard signal corresponding to the sensitive band in the standard waveform from a real signal to a complex signal using the Hilbert transform method, to obtain the transformed standard signal.

[0029] The separation module is used to separate the amplitude and phase in the transformed test signal to obtain a first amplitude and a first phase corresponding to the transformed test signal; and to separate the amplitude and phase in the transformed standard signal to obtain a second amplitude and a second phase corresponding to the transformed standard signal.

[0030] The analysis module is used to perform correlation analysis, distortion analysis, and maximum deviation analysis on the test signal and the standard signal based on the first amplitude, the first phase, the second amplitude, and the second phase.

[0031] Preferably, the analysis module includes:

[0032] The first analysis submodule is used to perform correlation analysis on the first amplitude and the second amplitude using the Pearson correlation analysis method to obtain the correlation coefficient between the first amplitude and the second amplitude; and to calculate the phase lock value using the first phase and the second phase.

[0033] The second analysis submodule is used to calculate the amplitude distortion using the first amplitude and the second amplitude, and to calculate the phase distortion using the first phase and the second phase;

[0034] The third analysis submodule is used to calculate the amplitude difference using the first amplitude and the second amplitude, and determine the maximum amplitude offset based on the amplitude difference; and to calculate the phase difference using the first phase and the second phase, and determine the maximum phase offset based on the phase difference.

[0035] Preferably, the power source of the power distribution automation terminal testing platform is a ZT3510S portable tester.

[0036] Preferably, the oscilloscope is a DPO5104B digital oscilloscope.

[0037] Preferably, the high-voltage probe is a TPP1000.

[0038] Preferably, the current transformer is model KCT16.

[0039] According to a second aspect of the embodiments of this application, a method for traceable measurement and evaluation of transient signals in a power distribution scenario is provided, including:

[0040] The power source of the power distribution automation terminal detection platform is used to simulate transient voltage / current signals.

[0041] The transient voltage / current signal is processed using a voltage / current processing unit to obtain a test signal;

[0042] When the oscilloscope receives the test signal, it generates the waveform of the test signal to obtain the test waveform.

[0043] The data processing unit performs quality analysis on the test signal based on the test waveform.

[0044] According to a third aspect of the present application, an electronic device is provided, comprising: at least one processor and a memory; wherein the memory and the processor are connected via a bus.

[0045] The memory is used to store one or more programs;

[0046] When the one or more programs are executed by the at least one processor, a method for traceable measurement and evaluation of transient signals in the power distribution scenario is implemented.

[0047] According to a fourth aspect of the embodiments of this application, a readable storage medium is provided, on which an executable program is stored, wherein when the executable program is executed, a method for traceable measurement and evaluation of transient signals in the power distribution scenario is implemented.

[0048] The technical solution provided by this invention has the following beneficial effects:

[0049] This invention provides a traceable measurement and evaluation system and method for transient signals in a power distribution scenario, comprising: a power source of a power distribution automation terminal detection platform, a voltage / current processing unit, an oscilloscope, and a data processing unit connected in sequence, with the voltage / current processing unit connected to the data processing unit; the power source of the power distribution automation terminal detection platform is used to simulate transient voltage / current signals and send the transient voltage / current signals to the voltage / current processing unit; the voltage / current processing unit is used to process the transient voltage / current signals to obtain test signals and send the test signals to the oscilloscope and the data processing unit; the oscilloscope is used to generate the waveform of the test signal after receiving the test signal, obtain the test waveform, and send the test waveform to the data processing unit; the data processing unit is used to perform quality analysis on the test signal based on the test waveform. This invention, by utilizing traceable instruments and equipment, achieves accurate measurement and quality evaluation of the transient signals output by the power source simulation, thereby further realizing the performance evaluation of the power source simulation output fault signals. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 This is a structural block diagram of a transient signal traceability measurement and evaluation system in a power distribution scenario provided by an embodiment of the present invention;

[0052] Figure 2 This is a schematic diagram of the key points of the fault provided in the embodiment of the present invention;

[0053] Figure 3 This is a waveform diagram of the current transformer performance verification results provided in an embodiment of the present invention;

[0054] Figure 4 This is a structural block diagram of the voltage measurement system provided in an embodiment of the present invention;

[0055] Figure 5 This is a structural block diagram of the current measurement system provided in an embodiment of the present invention;

[0056] Figure 6 This is a data processing flowchart provided in an embodiment of the present invention;

[0057] Figure 7 This is a schematic diagram of the critical fault points of the standard signal and test signal provided in the embodiments of the present invention;

[0058] Figure 8 This is an alignment diagram of the standard signal waveform and the measured signal waveform provided in the embodiments of the present invention;

[0059] Figure 9 This is a schematic diagram illustrating the selection of sensitive bands provided in an embodiment of the present invention;

[0060] Figure 10 This is a schematic diagram of the sensitive band intercepted according to an embodiment of the present invention;

[0061] Figure 11A This is a schematic diagram of the amplitude of the test signal and the standard signal provided in the embodiments of the present invention;

[0062] Figure 11B This is a schematic diagram of the point-by-point amplitude difference between the test signal and the standard signal provided in an embodiment of the present invention;

[0063] Figure 11C This is a schematic diagram of the phase of the test signal and the standard signal provided in an embodiment of the present invention;

[0064] Figure 11D This is a schematic diagram of the point-by-point phase difference between the test signal and the standard signal provided in an embodiment of the present invention;

[0065] Figure 12A This is a schematic diagram illustrating the trend of correlation with amplitude provided in an embodiment of the present invention;

[0066] Figure 12B This is a schematic diagram illustrating the trend of distortion as a function of amplitude, provided in an embodiment of the present invention.

[0067] Figure 12C This is a schematic diagram illustrating the trend of the maximum deviation versus amplitude provided in an embodiment of the present invention;

[0068] Figure 13 This is a flowchart of a method for traceable measurement and evaluation of transient signals in a power distribution scenario provided by an embodiment of the present invention;

[0069] Figure 14 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the following embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0071] Example 1

[0072] This invention provides a traceable measurement and evaluation system for transient signals in power distribution scenarios, such as... Figure 1 As shown, it includes: a power source, a voltage / current processing unit, an oscilloscope, and a data processing unit of the power distribution automation terminal detection platform connected in sequence, with the voltage / current processing unit connected to the data processing unit;

[0073] The power source of the power distribution automation terminal detection platform is used to simulate transient voltage / current signals and send the transient voltage / current signals to the voltage / current processing unit;

[0074] The voltage / current processing unit is used to process transient voltage / current signals to obtain test signals, and send the test signals to the oscilloscope and data processing unit;

[0075] An oscilloscope is used to generate the waveform of a test signal after receiving it, obtain the test waveform, and send the test waveform to the data processing unit.

[0076] The data processing unit is used to perform quality analysis on the test signal based on the test waveform.

[0077] This invention provides a traceable measurement and evaluation system for transient signals in power distribution scenarios. It is used for traceable measurement and quality evaluation of transient signals retrieved from power source transient signals of power distribution automation equipment, which facilitates quality inspection of power distribution automation equipment and the development of new technologies.

[0078] Furthermore, the voltage / current processing unit includes:

[0079] The high-voltage probes, connected to the power source and oscilloscope of the power distribution automation terminal testing platform respectively, are used to compress transient voltage signals to obtain test signals.

[0080] Furthermore, the voltage / current processing unit also includes:

[0081] Current transformers, connected to the power source and oscilloscope of the power distribution automation terminal testing platform respectively, are used to compress transient current signals to obtain test signals.

[0082] Furthermore, the data processing unit includes:

[0083] The alignment subunit is used to align the test waveform with a preset standard waveform to obtain the aligned test waveform;

[0084] The trimming sub-unit is used to trim sensitive bands in the standard waveform and sensitive bands in the aligned test waveform;

[0085] The analysis subunit is used to perform quality analysis on the test signal corresponding to the sensitive band in the aligned test waveform and the standard signal corresponding to the sensitive band in the standard waveform, using the sensitive band in the aligned test waveform and the sensitive band in the standard waveform.

[0086] Furthermore, aligning sub-units includes:

[0087] The first alignment module is used to align the test waveform forward with the standard waveform;

[0088] The second alignment module is used to delete invalid information at the rear end of the test waveform after the test waveform and the standard waveform are aligned forward, so that the test waveform and the standard waveform are aligned backward.

[0089] The test waveform refers to the output signal waveform of the power source, which is measured by an oscilloscope. The measurement result of the oscilloscope is considered to be the output signal of the power source. This signal is read from the oscilloscope in the form of a CSV file, which can be read into MATLAB. The original standard waveform is the transient fault signal written to the power source. The waveform file of this signal is in CFG format and is obtained from the fault site. The CFG file can be converted into a CSV file by the CAAP2008 software provided by the power source manufacturer, and then written to the FPGA of the power source as the input signal, i.e., the standard signal waveform.

[0090] Furthermore, the first alignment module is specifically used for:

[0091] Identify the critical points where faults occur in the test waveform and the standard waveform;

[0092] Subtract the number of points in the standard waveform corresponding to the key point from the number of points in the test waveform corresponding to the key point to obtain the first offset point number.

[0093] The test waveform is shifted forward by a first offset point to align it with the standard waveform.

[0094] Understandably, importing the CSV files of the test waveform and the standard waveform into MATLAB for plotting involves both types of waveforms, each containing a normal waveform and a fault waveform. The normal waveform is a periodic signal, while the fault waveform is a signal that has undergone a sudden change. This invention uses the first abrupt change point of a peak or trough as the critical point of the fault, such as... Figure 2 As shown in the figure, the marked points are the key points.

[0095] It should be noted that, with the point of failure as the reference point, the time corresponding to the point of failure is the time of failure, the waveform corresponding to the time before the time of failure is the forward direction of the waveform, and the front end of the waveform is the beginning end; the waveform corresponding to the time before the time of failure is the backward direction of the waveform, and the rear end of the waveform is the end end.

[0096] Furthermore, the sensitive bands in the standard waveform include: the bands corresponding to the first n1 cycles of the fault time in the standard waveform and the bands corresponding to the last n2 cycles of the fault time in the standard waveform.

[0097] The sensitive bands in the aligned test waveform include: the bands corresponding to the first n1 periods of the fault time in the test waveform and the bands corresponding to the last n2 periods of the fault time in the test waveform; where 0 <n1<n2。

[0098] It should be noted that the fault time is the moment the fault occurs. Since the standard signal has eight waveforms, and the fault time of all eight waveforms is the same, in order to detect the fault time in a timely manner, the moment when the fault first occurs in the eight waveforms is taken as the fault time of the entire standard waveform. Because the standard signal and the test signal have already been aligned before this, the fault time of the standard waveform is also the corresponding fault time of the test waveform.

[0099] Further analysis of sub-units includes:

[0100] The transformation module is used to convert the test signal corresponding to the sensitive band in the aligned test waveform from a real signal to a complex signal using the Hilbert transform method, to obtain the transformed test signal; and to convert the standard signal corresponding to the sensitive band in the standard waveform from a real signal to a complex signal using the Hilbert transform method, to obtain the transformed standard signal.

[0101] The separation module is used to separate the amplitude and phase in the transformed test signal to obtain the first amplitude and first phase corresponding to the transformed test signal; and to separate the amplitude and phase in the transformed standard signal to obtain the second amplitude and second phase corresponding to the transformed standard signal.

[0102] The analysis module is used to perform correlation analysis, distortion analysis, and maximum deviation analysis on the test signal and the standard signal based on the first amplitude, the first phase, the second amplitude, and the second phase.

[0103] Furthermore, the analysis module includes:

[0104] The first analysis submodule is used to perform correlation analysis on the first amplitude and the second amplitude using the Pearson correlation analysis method to obtain the correlation coefficient between the first amplitude and the second amplitude; and to calculate the phase lock value using the first phase and the second phase.

[0105] The second analysis submodule is used to calculate the amplitude distortion using the first amplitude and the second amplitude, and to calculate the phase distortion using the first phase and the second phase.

[0106] The third analysis submodule is used to calculate the amplitude difference using the first amplitude and the second amplitude, and to determine the maximum amplitude offset based on the amplitude difference; and to calculate the phase difference using the first phase and the second phase, and to determine the maximum phase offset based on the phase difference.

[0107] It should be noted that the Pearson correlation coefficient reflects the degree of correlation between two variables. Its value ranges from -1 to 1. The closer the absolute value is to 1, the stronger the correlation between the two variables; the closer it is to 0, the weaker the correlation.

[0108] The phase lock value reflects the degree of phase correlation between two variables. Its value ranges from 0 to 1. The closer the value is to 1, the higher the phase similarity; while the closer the value is to 0, the weaker the phase similarity.

[0109] The distortion calculated using amplitude and phase in this invention represents the magnitude of the difference between the amplitude and phase of two waveforms. The closer the distortion is to 0, the smaller the difference and the more similar the two waveforms are; the closer the distortion is to 1, the greater the difference and the less similar the two waveforms are.

[0110] This invention calculates the amplitude and phase offset at each point and takes out the maximum amplitude and phase offset. The maximum offset indicates that, under the condition that the situation remains unchanged, the deviation of the amplitude and phase of the two waveforms will not be greater than the maximum amplitude and phase offset. The smaller the maximum offset, the smaller the maximum allowable deviation and the more similar the two waveforms are.

[0111] Furthermore, the power source model of the power distribution automation terminal testing platform can be, but is not limited to, the ZT3510S portable tester.

[0112] Furthermore, the oscilloscope model can be, but is not limited to, the DPO5104B digital oscilloscope.

[0113] Furthermore, the high-voltage probe model can be, but is not limited to, TPP1000.

[0114] Furthermore, the model of the current transformer can be, but is not limited to, KCT16.

[0115] The transient signal traceability measurement and evaluation system provided by this invention in power distribution scenarios uses a high-voltage probe, current transformer, and oscilloscope as measuring instruments and a power source of the power distribution automation terminal detection platform as a signal generating instrument, thereby achieving relatively accurate measurement of transient signals. The test waveform is compared with the standard waveform point by point and overall to obtain the differences between the two, thus realizing the quality evaluation of the output waveform of the power source of the power distribution automation terminal detection platform.

[0116] The transient signal traceability measurement and evaluation system for power distribution scenarios provided by this invention selects high-voltage probes, current transformers, and oscilloscopes as measuring instruments and a power source of the power distribution automation terminal detection platform as a signal generating instrument as a standard. The technical parameters of these standards can be traced back to national voltage and time frequency parameter benchmarks. The transient signal parameters measured by this system can be traced back to national voltage and time frequency parameter benchmarks.

[0117] To further illustrate the transient signal traceability measurement and evaluation system in the aforementioned power distribution scenario, this invention provides a specific experimental example, as shown below:

[0118] The power source for the power distribution automation terminal testing platform uses a ZT3510S portable tester, with a voltage analog output range of 0-200V and a current analog output range of 0-15A. This power source has two wiring options: electronic and electromagnetic. This test uses the electromagnetic connection. Before connecting the power source, the current circuit must be short-circuited, and the voltage circuit must be open-circuited.

[0119] The oscilloscope used is a Tektronix DPO5104B digital oscilloscope, which has a -3dB bandwidth of 1GHz, an effective bit depth of 6 bits, a maximum input voltage of 20V, a maximum sampling rate of 5GS / s, and four input channels. In this experiment, there were 13993 points, a sampling duration of 279.840ms, and a sampling rate of 50000Hz. To ensure the oscilloscope could display the waveform completely and that each point corresponded correctly, the horizontal sensitivity was adjusted to 50.0ms / div, and the sampling rate was adjusted to 50.0kS / s. The vertical sensitivity needed to be adjusted according to the amplitude order of the different signals.

[0120] The high-voltage probe used is the Tektronix TPP1000, which has a -3dB bandwidth of 1000MHz, 10X attenuation, and a maximum input voltage of 300V. It is a high-bandwidth general-purpose probe from Tektronix. In this experiment, this high-voltage probe was used to compress the voltage input to the oscilloscope, ensuring that it did not exceed the voltage range that the oscilloscope could withstand.

[0121] The current transformer used is the Dingben KCT16, which operates at a frequency of 50-2kHz and has a rated input of 0-2000A. This experiment utilizes its characteristic of 100A input and 0.333V output to handle large currents, avoiding exceeding the oscilloscope's range.

[0122] To verify the functionality of the current transformer, different currents were input, the corresponding output voltages were measured, and their ratios were calculated. The results of the current transformer performance verification are shown in Table 1. Figure 3It can be visually observed that the input and output of the current transformer are basically linear. However, actual measurements revealed that the proportional relationship differs slightly from the nominal value of 100A:0.333V. Therefore, the actual measured proportional relationship will be used as the standard in subsequent data processing.

[0123] Table 1 Performance verification results of current transformers

[0124] Input current Output voltage Proportion 1A 0.003395V 0.003395 2A 0.006785V 0.0033925 5A 0.001696V 0.003392 10A 0.0033935V 0.0033935

[0125] Based on the functional characteristics of the aforementioned components and instruments, an overall measurement system can be constructed. Since this power source has four voltage outputs and four current outputs, different measurement schemes are available for current and voltage.

[0126] For voltage measurement, a digital waveform file is written to a power source, enabling the power source to output an analog voltage. Since the oscilloscope can only withstand a maximum voltage of 20V, while the power source's analog output voltage can reach nearly 200V, significantly exceeding the oscilloscope's range, a high-voltage probe is used to proportionally compress the power source's analog output voltage, allowing it to safely pass through the oscilloscope. The voltage measurement system is as follows: Figure 4 As shown.

[0127] For current measurement, the initial setup is basically the same as for voltage measurement. Since the maximum current an oscilloscope can handle is much smaller than the analog output current of the power source, a current transformer is used to proportionally compress the large current into a smaller current, allowing the oscilloscope to acquire the reduced current signal waveform data. The current measurement system is as follows: Figure 5 As shown.

[0128] Based on the above measurement scheme, a practical physical measurement system can be constructed. When measuring voltage, the power source simulates a large voltage output. The positive and negative terminals of the power source voltage being measured are connected to the positive and negative terminals of the high-voltage probe, respectively, and then the high-voltage probe is connected to the oscilloscope channel.

[0129] When measuring current, the power source simulates a large current output. Connect the current transformer to the current-measuring terminal of the power source according to the positive and negative directions, and then connect the current transformer to the oscilloscope channel through a BNC coaxial cable.

[0130] By following the steps above, the test waveform can be exported via an oscilloscope for data processing. The data processing flow is as follows: Figure 6 As shown, the test waveform is the waveform data acquired by the oscilloscope, and the standard waveform is the waveform data before it was manually written to the power source.

[0131] The test waveform must be aligned with the standard waveform. During measurement, the timing of the power source's simulated output is manually made random, so the occurrence time of the measured waveform is also random. After acquiring the power source's simulated output through an oscilloscope, there will be a section of invalid information at the beginning and end of the test waveform. Therefore, it is necessary to align the test waveform with the standard waveform to ensure that the occurrence time of a certain point corresponds.

[0132] First, align the standard and test waveforms forward. Import the CSV files of the standard and test waveforms into MATLAB. After generating the waveforms, find the key points where the two signals malfunction. Subtract the number of points in the standard signal from the number of key points in the test signal to find the offset x. Shift the test signal forward by x points to align the standard and test signals forward.

[0133] Specifically, the formula for calculating the number of offset points includes:

[0134] x = ab

[0135] In the above formula, a is the critical fault point of the test signal, b is the critical fault point of the standard signal, and x is the number of offset points.

[0136] Taking the alignment of a set of waveforms as an example, such as Figure 7 As shown, the blue line represents the standard signal, and the orange line represents the test signal. The critical fault point of the standard signal is 6261, and the corresponding critical fault point of the test signal is 11581, i.e., a = 11581, b = 6261, x = ab = 5320. This means the original test signal had 5320 invalid bits at the beginning. Deleting these bits completes the front alignment between the standard and test signals. It can be understood that the signal corresponding to the standard waveform is the standard signal itself.

[0137] Next, the standard waveform and the test waveform are back-aligned. After front alignment, the points at the beginning of the standard signal and the test signal correspond one-to-one; only a portion of invalid information at the end of the test signal needs to be deleted. In this example, the standard signal has 13993 points; that is, after front alignment, deleting the data after the 13993rd point of the test signal completes the back alignment. Figure 8 As shown.

[0138] During measurement, it is necessary to ensure that the oscilloscope's sampling rate and horizontal sensitivity meet the requirements of this waveform, that is, all points generated by the standard waveform are acquired.

[0139] After alignment, sensitive bands are cropped, that is, the bands of greater experimental interest.

[0140] The key waveform segments selected for this experiment were the half-cycle before the fault occurred and the two cycles after the fault occurred. Observing the standard signal using CAAP2008 software revealed... Figure 9 The area within the red box shown is the part of interest, specifically points 4904 to 7868 of the standard waveform. Figure 8 Taking the two waveforms from point 4904 to point 7868, we get... Figure 10 The sensitive bands shown are the bands of interest for this experiment. Figure 10 In the diagram, the blue line represents the standard signal, and the orange line represents the test signal.

[0141] After waveform alignment and cropping of sensitive bands, the quality of the cropped signal is evaluated.

[0142] To evaluate the quality of transient signals output by a power source, the test signal needs to be compared with the original signal. This is mainly done by considering both amplitude and phase. The Hilbert transform is used to convert the test signal corresponding to the sensitive band from a real signal into a complex signal, which allows for the separation of the signal's amplitude and phase.

[0143] The Hilbert transform formula is shown below:

[0144]

[0145] In the above formula, x(t) is the original signal. H[x(t)] represents the signal after Hilbert transform, τ is the shift unit in Hilbert's algorithm, t is time, and x(τ) is the amplitude of the original signal at time τ.

[0146] Compared to the signal H[x(t)] after Hilbert transform, the amplitude of the original signal x(t) remains unchanged, but the phase shifts by 90°. Since the subsequent processing uses the phase difference between the two signals, and the phases of both the standard signal and the test signal are shifted by 90° after the Hilbert transform, this will not affect the experimental results.

[0147] The following section evaluates the correlation, distortion, and maximum deviation of the test signal and the standard signal.

[0148] Correlation has two aspects. One is magnitude correlation, described by the Pearson correlation coefficient. The Pearson correlation coefficient can be used to measure the degree of linear correlation between data. In the output range of [-1, 1], the closer the output value is to 1, the stronger the positive correlation; the closer it is to -1, the stronger the negative correlation; and an output value of 0 indicates no correlation. The Pearson correlation coefficient, based on Euclidean distance to represent similarity, centers the calculated values. Its calculation formula is as follows:

[0149]

[0150] In the above formula, j∈[1,n], n is the number of points in the standard signal and the measured signal; r is the correlation coefficient between the standard signal and the measured signal, x j Let y be the amplitude at the j-th point of the standard signal. j Let y be the amplitude of the measured signal at the j-th point, x be the average amplitude of the standard signal, and y be the average amplitude of the measured signal.

[0151] On the other hand, there is phase correlation, described by the phase lock value (PLV). The PLV is widely used to investigate the phase synchronization of two different rhythms; its magnitude is independent of the signal amplitude. The PLV value is between 0 and 1, where 1 represents complete synchronization and 0 represents complete desynchronization. The calculation formula is as follows:

[0152]

[0153] In the above formula, m∈[1,N], N is the number of points in the waveform; i is the imaginary unit, Φ m This represents the phase difference between the two waveforms, which must be expressed in radians.

[0154] Distortion can be used to characterize the degree to which a test signal deviates from a standard signal. In this experiment, two aspects of signal distortion were considered: amplitude distortion and phase distortion. Traditionally, distortion is defined as the distortion of a sine wave, but there are almost no descriptions of distortion for transient signals. Therefore, this invention defines the distortion of the power source's analog output signal as follows:

[0155]

[0156] Taking amplitude distortion as an example, the principle is to first match the test signal with the standard signal one by one, then subtract the amplitude of the test signal from the amplitude of each point of the standard signal, calculate the absolute value of the difference for each point, sum the absolute value of the difference with the amplitude of the standard signal, and then compare them to obtain the amplitude distortion.

[0157] In this experiment, 2963 waveform points need to be processed, yielding the amplitude and phase differences for each of these 2963 corresponding points. Therefore, the maximum amplitude offset Fmax and maximum phase offset Amax for each waveform group can be obtained. It can be assumed that when the power source outputs a signal of this order of magnitude, the maximum amplitude offset will not exceed Fmax, and the maximum phase offset will not exceed Amax.

[0158] To fully demonstrate the consistency of the power source's output waveform quality under different current and voltage conditions, this experiment set up four amplitude ranges for voltage and current. The four amplitude ranges for voltage were -11V to +11V, -50V to +50V, -120V to +120V, and -195V to 195V, and the four amplitude ranges for current were -0.4A to +0.4A, -4A to 4A, -5A to 5A, and -9.5A to 9.5A. The voltage and current measurements for these four amplitude ranges were repeated five times, and the waveform quality was then evaluated using the above parameters. The following uses voltage as an example.

[0159] First, a point-by-point waveform quality assessment is performed. This assessment primarily considers amplitude and phase. The amplitude and phase of the aligned standard signal and the measured signal are subtracted point by point to obtain the amplitude difference and phase difference of the point-by-point waveforms. The following example uses an analog output voltage ranging from -50V to +50V.

[0160] Figures 11A-11D These are, respectively, point-by-point signal amplitude waveform, point-by-point amplitude difference waveform, point-by-point phase waveform, and point-by-point phase difference waveform.

[0161] Quality assessment of the power source's analog output signal can be more intuitively observed by analyzing it point by point. However, due to the large number of points, it is essential to find a reasonable set of parameters to complete the quality assessment. In the experiment, amplitude correlation and phase lock-in value were used to describe the degree of correlation; amplitude distortion and phase distortion were used to describe the degree of distortion; and maximum amplitude offset and maximum phase offset were used to describe the degree of maximum offset. Taking an analog output voltage of -50V to 50V as an example, the processing results are shown in Table 2.

[0162] Table 2 Overall Waveform Evaluation Table for -50V~50V Analog Output Voltage

[0163]

[0164]

[0165] Following the above procedure, and so on, the amplitude correlation, phase lock value, amplitude distortion, phase distortion, maximum amplitude offset, and maximum phase offset for the four amplitude segments are obtained. As shown in Table 3, the data in Table 3 are the average values ​​after five measurements.

[0166] Table 3 Waveform quality assessment table for four levels of analog output voltage

[0167]

[0168] To make the data in the table above more intuitive, plot the trend of the corresponding indicators as the amplitude changes, such as... Figure 12A , 12BAnd 12C. According to Table 2, Table 3 and Figure 12A -C shows that the correlation of the power source is very close to 1 in the range of 50V-200V; the distortion is even lower at 50V and 120V, very close to 0; the maximum deviation is at low amplitude, with a larger phase deviation, and the others increase slightly with the increase of amplitude.

[0169] In the above example, the transient signal of the power source was measured by the transient signal traceability measurement and evaluation system in the power distribution scenario; and the waveform data of the repeated measurement five times were processed and analyzed to realize the measurement and quality evaluation of the transient signal of the power source.

[0170] In the above examples, traceable measurements of transient signals are performed using an oscilloscope and current- and voltage-reducing components. When measuring transient voltage, an oscilloscope, a high-voltage probe, and a power source from a power distribution automation terminal testing platform are used. When measuring transient current, an oscilloscope, a current transformer, and a power source from the same platform are used. All the oscilloscopes, high-voltage probes, and current transformers used are traceable components certified by a metrology and testing institution.

[0171] The power system is responsible for supplying electricity to people's lives. If the power system fails, it directly affects the quality of life and can even endanger human safety. Simulating a power system fault signal using a power source and inputting it into the distribution system's safety equipment allows for testing the fault detection performance of the equipment. Therefore, the performance of the power source's simulated fault waveform is a crucial prerequisite. This invention provides a traceable measurement and evaluation system for transient signals in a power distribution scenario. By utilizing traceable measuring instruments, it achieves accurate measurement and quality evaluation of the power source's simulated transient output signal, thereby enabling performance evaluation of the power source's simulated fault output signal.

[0172] Example 2

[0173] This invention provides a method for traceable measurement and evaluation of transient signals in power distribution scenarios, such as... Figure 13 As shown, it includes the following steps:

[0174] Step 101: Simulate transient voltage / current signals using the power source of the power distribution automation terminal detection platform;

[0175] Step 102: Process the transient voltage / current signal using the voltage / current processing unit to obtain the test signal;

[0176] Step 103: When the oscilloscope receives the test signal, it generates the waveform of the test signal to obtain the test waveform;

[0177] Step 104: Use the data processing unit to perform quality analysis on the test signal based on the test waveform.

[0178] Further, step 102 includes:

[0179] The transient voltage signal is compressed using the high-voltage probe in the voltage / current processing unit to obtain the test signal.

[0180] Furthermore, step 102 also includes:

[0181] The current transformer in the voltage / current processing unit is used to compress the transient current signal to obtain the test signal.

[0182] Further, step 104 includes:

[0183] Step 1041: Align the test waveform with the preset standard waveform to obtain the aligned test waveform;

[0184] Step 1042: Trim the sensitive bands from the standard waveform and the aligned test waveform;

[0185] Step 1043: Using the sensitive bands in the aligned test waveform and the sensitive bands in the standard waveform, perform quality analysis on the test signal corresponding to the sensitive band in the aligned test waveform and the standard signal corresponding to the sensitive band in the standard waveform.

[0186] Further, step 1041 includes:

[0187] Step 1041a: Align the test waveform with the standard waveform forward;

[0188] Step 1041b: After the test waveform and the standard waveform are aligned forward, delete the invalid information at the end of the test waveform so that the test waveform and the standard waveform are aligned backward.

[0189] Further, step 1041a includes:

[0190] Identify the critical points where faults occur in the test waveform and the standard waveform;

[0191] Subtract the number of points in the standard waveform corresponding to the key point from the number of points in the test waveform corresponding to the key point to obtain the first offset point number.

[0192] The test waveform is shifted forward by a first offset point to align it with the standard waveform.

[0193] Furthermore, the sensitive bands in the standard waveform include: the bands corresponding to the first n1 cycles of the fault time in the standard waveform and the bands corresponding to the last n2 cycles of the fault time in the standard waveform.

[0194] The sensitive bands in the aligned test waveform include: the bands corresponding to the first n1 periods of the fault time in the test waveform and the bands corresponding to the last n2 periods of the fault time in the test waveform; where 0 <n1<n2。

[0195] Further, step 1043 includes:

[0196] Step 1043a: Use the Hilbert transform method to convert the test signal corresponding to the sensitive band in the aligned test waveform from a real signal to a complex signal to obtain the transformed test signal; and use the Hilbert transform method to convert the standard signal corresponding to the sensitive band in the standard waveform from a real signal to a complex signal to obtain the transformed standard signal.

[0197] Step 1043b: Separate the amplitude and phase of the transformed test signal to obtain the first amplitude and first phase of the transformed test signal; and separate the amplitude and phase of the transformed standard signal to obtain the second amplitude and second phase of the transformed standard signal.

[0198] Step 1043c: Based on the first amplitude, the first phase, the second amplitude, and the second phase, perform correlation analysis, distortion analysis, and maximum deviation analysis on the test signal and the standard signal.

[0199] Further, step 1043c includes:

[0200] The correlation coefficient between the first and second amplitudes was obtained by using Pearson correlation analysis; and the phase lock value was calculated using the first and second phases.

[0201] Amplitude distortion is calculated using the first amplitude and the second amplitude, and phase distortion is calculated using the first phase and the second phase.

[0202] Using the first amplitude and the second amplitude, the amplitude difference is calculated, and the maximum amplitude offset is determined based on the amplitude difference; and using the first phase and the second phase, the phase difference is calculated, and the maximum phase offset is determined based on the phase difference.

[0203] It is understood that the method embodiments provided above correspond to the system embodiments described above, and the specific details can be referred to each other, which will not be repeated here.

[0204] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0205] Example 3

[0206] like Figure 14 As shown, the present invention also provides an electronic device, which may be a computer device, a microcontroller device, a smart mobile device, etc. The electronic device in this embodiment may include a processor, a memory, a transceiver component, etc. The memory, processor, and transceiver component are connected via a bus; the memory can be used to store executable programs, and an exemplary executable program may include instructions; the processor is used to execute the instructions stored in the memory. The memory can also be used to store data, which can be accessed and / or modified when instructions are executed.

[0207] The processor may be a Central Processing Unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, and it is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the storage medium to realize the corresponding method flow or corresponding function, so as to realize the steps of the transient signal traceability measurement and evaluation method in a power distribution scenario in the above embodiment.

[0208] Example 4

[0209] Based on the same inventive concept, this invention also provides a readable storage medium, specifically an electronic device readable storage medium (Memory). This readable storage medium is a memory device within an electronic device used to store programs and data. It is understood that the storage medium here can include both built-in storage media within the electronic device and extended storage media supported by the electronic device. The storage medium provides storage space, which stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more executable programs (including program code). It should be noted that the storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. Loading and executing one or more instructions stored in the storage medium by the processor can implement the steps of the transient signal traceability measurement and evaluation method in a power distribution scenario described in the above embodiments.

[0210] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0211] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0212] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0213] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0214] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A transient signal traceability measurement and evaluation system for power distribution scenarios, characterized in that, include: The power source, voltage / current processing unit, oscilloscope and data processing unit of the power distribution automation terminal detection platform are connected in sequence, and the voltage / current processing unit is connected to the data processing unit. The power source of the power distribution automation terminal detection platform is used to simulate transient voltage / current signals and send the transient voltage / current signals to the voltage / current processing unit; The voltage / current processing unit is used to process the transient voltage / current signal to obtain a test signal, and send the test signal to the oscilloscope and the data processing unit; The oscilloscope is used to generate the waveform of the test signal after receiving the test signal, obtain the test waveform, and send the test waveform to the data processing unit. The data processing unit is used to perform quality analysis on the test signal based on the test waveform.

2. The system according to claim 1, characterized in that, The voltage / current processing unit includes: A high-voltage probe, connected to the power source of the power distribution automation terminal testing platform and the oscilloscope respectively, is used to compress the transient voltage signal to obtain the test signal.

3. The system according to claim 1, characterized in that, The voltage / current processing unit further includes: The current transformers connected to the power source of the power distribution automation terminal detection platform and the oscilloscope are used to compress the transient current signal to obtain the test signal.

4. The system according to claim 1, characterized in that, The data processing unit includes: The alignment subunit is used to align the test waveform with a preset standard waveform to obtain the aligned test waveform; The trimming subunit is used to trim the sensitive bands in the standard waveform and the sensitive bands in the aligned test waveform; The analysis subunit is used to perform quality analysis on the test signal corresponding to the sensitive band in the aligned test waveform and the standard signal corresponding to the sensitive band in the standard waveform using the sensitive band in the aligned test waveform and the sensitive band in the standard waveform.

5. The system according to claim 4, characterized in that, The alignment subunit includes: The first alignment module is used to align the test waveform forward with the standard waveform; The second alignment module is used to delete invalid information at the rear end of the test waveform after the test waveform and the standard waveform are aligned forward, so that the test waveform and the standard waveform are aligned backward.

6. The system according to claim 5, characterized in that, The first alignment module is specifically used for: Identify the critical points where faults occur in the test waveform and the standard waveform; Subtract the number of points in the standard waveform corresponding to the key point from the number of points in the test waveform corresponding to the key point to obtain the first offset point number. The test waveform is shifted forward by a first offset point number so that the test waveform is aligned forward with the standard waveform.

7. The system according to claim 4, characterized in that, The sensitive bands in the standard waveform include: the bands corresponding to the first n1 periods of the fault time in the standard waveform and the bands corresponding to the last n2 periods of the fault time in the standard waveform. The sensitive bands in the aligned test waveform include: the bands corresponding to the first n1 periods of the fault time in the test waveform and the bands corresponding to the last n2 periods of the fault time in the test waveform; wherein, 0 <n1<n2。 8. The system according to claim 4, characterized in that, The analysis subunit includes: The transformation module is used to convert the test signal corresponding to the sensitive band in the aligned test waveform from a real signal to a complex signal using the Hilbert transform method, to obtain the transformed test signal; and to convert the standard signal corresponding to the sensitive band in the standard waveform from a real signal to a complex signal using the Hilbert transform method, to obtain the transformed standard signal. The separation module is used to separate the amplitude and phase in the transformed test signal to obtain a first amplitude and a first phase corresponding to the transformed test signal; and to separate the amplitude and phase in the transformed standard signal to obtain a second amplitude and a second phase corresponding to the transformed standard signal. The analysis module is used to perform correlation analysis, distortion analysis, and maximum deviation analysis on the test signal and the standard signal based on the first amplitude, the first phase, the second amplitude, and the second phase.

9. The system according to claim 8, characterized in that, The analysis module includes: The first analysis submodule is used to perform correlation analysis on the first amplitude and the second amplitude using the Pearson correlation analysis method to obtain the correlation coefficient between the first amplitude and the second amplitude; and to calculate the phase lock value using the first phase and the second phase. The second analysis submodule is used to calculate the amplitude distortion using the first amplitude and the second amplitude, and to calculate the phase distortion using the first phase and the second phase; The third analysis submodule is used to calculate the amplitude difference using the first amplitude and the second amplitude, and determine the maximum amplitude offset based on the amplitude difference; and to calculate the phase difference using the first phase and the second phase, and determine the maximum phase offset based on the phase difference.

10. The system according to claim 1, characterized in that, The power source of the power distribution automation terminal testing platform is a ZT3510S portable tester.

11. The system according to claim 1, characterized in that, The oscilloscope is a DPO5104B digital oscilloscope.

12. The system according to claim 2, characterized in that, The high-voltage probe is model TPP1000.

13. The system according to claim 1, characterized in that, The current transformer is model KCT16.

14. A method for traceable measurement and evaluation of transient signals in a power distribution scenario, characterized in that, include: The power source of the power distribution automation terminal detection platform is used to simulate transient voltage / current signals. The transient voltage / current signal is processed using a voltage / current processing unit to obtain a test signal; When the oscilloscope receives the test signal, it generates the waveform of the test signal to obtain the test waveform. The data processing unit performs quality analysis on the test signal based on the test waveform.

15. An electronic device, characterized in that, include: At least one processor and memory; The memory and processor are connected via a bus; The memory is used to store one or more programs; When the one or more programs are executed by the at least one processor, the transient signal traceability measurement and evaluation method in the power distribution scenario as described in claim 14 is implemented.

16. A readable storage medium, characterized in that, It contains an execution program, which, when executed, implements the transient signal traceability measurement and evaluation method in the power distribution scenario as described in claim 14.

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