Method and device for automatic measurement of lightning surge impulse parameters, medium
By using automated filtering and interpolation calculation methods, the time consumption and error problems in lightning surge pulse parameter measurement were solved, enabling fast and accurate automatic measurement of lightning surge pulse parameters and improving testing efficiency and accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- INST OF ELECTRONICS CHINA ACAD OF TESTING TECH
- Filing Date
- 2022-01-21
- Publication Date
- 2026-06-23
Smart Images
Figure CN114527332B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of pulse signal detection technology, and more specifically, to an automatic measurement method, device, and medium for lightning surge pulse parameters. Background Technology
[0002] High-energy pulses from lightning surges pose a significant threat to electronic equipment. There are two main sources of lightning surge interference: one is the common natural phenomenon of lightning strikes. When lightning strikes outdoor power lines or the ground with a grounding system, it generates pulse voltages and currents in indoor lines through direct coupling or indirect coupling via induced electromagnetic fields. The other source is the operation of power transmission line switches. Short circuits between lines, arc faults, and capacitor bank switching can generate voltage and current pulse interference. It has been reported that one of the major causes of the devastating Wenzhou train accident on July 23, 2011, was equipment failure caused by a lightning strike. Therefore, when the source of interference cannot be completely eliminated, the only way to mitigate its adverse effects is to improve the anti-interference capabilities of electronic equipment. Therefore, before electronic products are used normally, it is necessary to use a lightning surge simulator to generate lightning surge pulses that meet national standards to test the product's anti-interference level.
[0003] Lightning surge pulse waveform data processing is complex, as some parameters differ from those of common pulse waveforms, and some measurement results need to be multiplied by a coefficient.
[0004] Common pulse parameter definitions:
[0005] Pulse amplitude Vm: The maximum value of the pulse waveform change.
[0006] Rise time Tr: The time required for the pulse waveform to rise from 0.1Vm to 0.9Vm.
[0007] Duration Td: The time required for the pulse to rise from 0.5Vm to fall from 0.5Vm.
[0008] Lightning surge pulse parameter definitions:
[0009] Pulse amplitude Vm: The maximum value of the pulse waveform change.
[0010] Voltage waveform parameters:
[0011] Voltage rise time Tr: 1.67 times the time interval between the two points of 0.3Vm and 0.9Vm of the pulse waveform.
[0012] Voltage duration Td: The time required for the pulse to rise from 0.5Vm to fall from 0.5Vm.
[0013] Current waveform parameters:
[0014] Current rise time Tr: 1.25 times the time interval between the two points of 0.1Vm and 0.9Vm of the pulse waveform.
[0015] The current (differential mode) duration Td is 1.18 times the time interval between the rising segment 0.5Vm and the falling segment 0.5Vm of the pulse.
[0016] Current (common mode) duration Td: 1.04 times the time interval between the pulse rise segment 0.5Vm and the fall segment 0.5Vm.
[0017] Currently, such as Figure 1 As shown, the processing flow for the output pulse waveform of the lightning surge simulator is as follows: first, an oscilloscope is used with a voltage probe and a current sensor to collect the output voltage and current pulse waveforms respectively.
[0018] Its main drawback is:
[0019] Defect 1: The oscilloscope cannot automatically measure the surge pulse waveform parameters; they can only be obtained by manually operating the oscilloscope scale and multiplying the result by a coefficient. To ensure accurate measurement, the manual measurement process requires several waveform scaling operations, resulting in a long data processing time for a single pulse. Evaluating lightning surge simulators requires examining voltage and current waveforms under different polarities, voltage levels, and output ports. Obtaining a complete set of parameters consumes significant time and manpower in data processing.
[0020] Defect 2: The oscilloscope scale can only fall on the actual sampling point, while the actual measurement position of the pulse waveform may fall between two sampling points, resulting in a large measurement error. Summary of the Invention
[0021] To address the shortcomings of large image acquisition and spectral aliasing in modulation measurement profilometry, this invention provides an automatic measurement method, device, and medium for lightning surge pulse parameters, effectively solving the technical problems mentioned in the background art.
[0022] The specific technical solution of the present invention is as follows:
[0023] According to the first technical solution of the present invention, an automatic measurement method for lightning surge pulse parameters is provided, comprising the following steps: acquiring a pulse waveform data set, the pulse waveform data set including actual collected sampling points, the sampling points including time and amplitude parameters; filtering the data of the sampling points; extracting the part related to pulse parameter measurement from the filtered data of the sampling points, removing useless sampling points, and obtaining the effective part of the pulse; based on the effective part of the pulse, splitting the effective part of the pulse into rising edge and falling edge, with the maximum peak value of the pulse waveform as the boundary or the minimum peak value of the pulse waveform as the boundary; interpolating between sampling points on both sides of the target point required for pulse parameter measurement; measuring and calculating the peak value, wavefront time, and duration based on the sampling points and interpolation points.
[0024] According to a second technical solution of the present invention, an automatic measurement device for lightning surge pulse parameters is provided, comprising a sampling device and a processor, wherein the sampling device is signal-connected to the processor; the sampling device is configured to: acquire a pulse waveform data set and transmit it to the processor; the processor is configured to: acquire the pulse waveform data set, the pulse waveform data set including actually acquired sampling points, the sampling points including time and amplitude parameters; filter the data of the sampling points; extract the part related to pulse parameter measurement from the filtered sampling point data, remove useless sampling points, and obtain the effective part of the pulse; based on the effective part of the pulse, divide the effective part of the pulse into rising edge and falling edge, with the maximum peak value of the pulse waveform as the boundary or the minimum peak value of the pulse waveform as the boundary; interpolate between the sampling points on both sides of the target point required for pulse parameter measurement; and measure and calculate the peak value, wavefront time, and duration based on the sampling points and interpolation points.
[0025] According to a third technical solution of the present invention, a computer-readable storage medium is provided, on which computer-readable instructions are stored, which, when executed by a computer processor, cause the computer to perform the method described in any embodiment of the present invention.
[0026] The present invention discloses an automatic measurement method, apparatus, and medium for lightning surge pulse parameters, which significantly improves the degree of automation and testing efficiency. Because interpolation calculations are performed between actual sampling points, the measurement results are more accurate. According to actual needs, accurate measurement can be performed at any point on the entire pulse waveform. Attached Figure Description
[0027] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.
[0028] Figure 1 A schematic diagram of waveform measurement principle in the prior art is shown;
[0029] Figure 2 A flowchart of an automatic measurement method for lightning surge pulse parameters according to an embodiment of the present invention is shown.
[0030] Figure 3 A pulse waveform diagram before filtering is shown according to an embodiment of the present invention.
[0031] Figure 4 The filtered pulse waveform according to an embodiment of the present invention is shown.
[0032] Figure 5 A waveform diagram of the effective portion of a pulse according to an embodiment of the present invention is shown.
[0033] Figure 6 A pulse waveform diagram of the rising edge according to an embodiment of the present invention is shown.
[0034] Figure 7 A pulse waveform diagram of the falling edge according to an embodiment of the present invention is shown.
[0035] Figure 8 A schematic diagram of interpolation between pulse waveform arrays according to an embodiment of the present invention is shown.
[0036] Figure 9 A schematic diagram illustrating the working principle of the sampling device of an automatic measurement device for lightning surge pulse parameters according to an embodiment of the present invention is shown.
[0037] Figure 10 A schematic diagram illustrating the working principle of the sampling device of an automatic measurement device for lightning surge pulse parameters according to an embodiment of the present invention is shown. Detailed Implementation
[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
[0040] The invention will now be further described with reference to the accompanying drawings.
[0041] Figure 2 A flowchart illustrating an automatic measurement method for lightning surge pulse parameters according to an embodiment of the present invention is shown. Figure 2 As shown, this embodiment of the invention provides an automatic measurement method for lightning surge pulse parameters. The automatic measurement method begins in step S100, acquiring a pulse waveform data set. The pulse waveform data set includes actually acquired sampling points, and each sampling point contains time and amplitude parameters. The number of sampling points equals the sampling rate multiplied by the sampling duration.
[0042] In step S200, the data of the sampling points is filtered. The filtering process involves replacing the value of a point in the array with the median value of all points in its neighborhood, making it closer to the true value, thereby eliminating noise.
[0043] In some embodiments, the data of the sampling points are filtered. Before and after filtering, the total number of sampling points remains unchanged, and the sampling order of each sampling point remains unchanged.
[0044] In some embodiments, the data of the sampling points are filtered using the following method:
[0045] Extract the amplitude data group Y of each sampling point in the pulse waveform data group, and represent it as Y = {y i}, i=0, 1, 2,..., n-1;
[0046] The filtered amplitude data set Y' is obtained using the following equation:
[0047] y i =Median(J) i ),i=0,1,2,…,n-1,
[0048] J i ={y i–rl ,y i–rl+1 ,…,y i–1 ,y i ,y i+1 ,…,y i+rr–1 ,y i+rr},
[0049] In the formula, y i ' is an element of the filtered amplitude data group Y'; J iFor the amplitude data group Y at each sampling point, the i-th element y i The nearest neighbor subset centered at y; rl is y i Number of elements on the left; rr is y i Number of elements on the right.
[0050] Figure 3 A pulse waveform diagram before filtering is shown according to an embodiment of the present invention. Figure 4 The filtered pulse waveform according to an embodiment of the present invention is shown. Figure 3 and Figure 4 As shown, it is obvious that after filtering according to the embodiments of the present invention, noise can be significantly eliminated to ensure the accuracy of pulse parameter measurement.
[0051] In step S300, the pulse parameter measurement-related portion is extracted from the filtered sampling data, and useless sampling points are removed to obtain the effective portion of the pulse. Specifically, this is achieved by filtering the amplitude values of the sampling points, retaining only 1% of the sampling points whose amplitude is greater than the peak value. The waveform of the obtained effective portion of the pulse is shown below. Figure 5 As shown.
[0052] In step S400, based on the effective portion of the pulse, the effective portion of the pulse is divided into rising edge and falling edge, with the maximum peak value of the pulse waveform as the boundary or the minimum peak value of the pulse waveform as the boundary.
[0053] In some embodiments, the splitting method may be: extracting three feature sampling points of the effective portion of the pulse, wherein the three feature sampling points are the starting point (x0, y0) and the maximum value (x0, y0) of the effective pulse waveform array, respectively. p y p ) and endpoint (x) n-1 y n-1 ); Split to obtain two new arrays, with the rising edge of array D1 = (x i y i ), i = 0, 1, 2, ..., p; falling edge array D2 = (x i’ y i’ ), i'=p+1, p+2, p+3,..., n-1.
[0054] After splitting, the pulse waveforms of the rising and falling edges are as follows: Figure 6 and Figure 7 As shown.
[0055] In step S500, the target point is measured according to the pulse parameters, and interpolation is performed between the sampling points on both sides of it.
[0056] For example, taking the processing of the ascending segment as an example, the interpolation method is to scan the monotonically ascending segment array D1 = (xi y i ), i = 0, 1, 2, ..., p. If the target location (x, y) is in array D1, there exists y = y i The interpolation function outputs the corresponding time x at this moment. i When the target position (x, y) is not in array D1, there exists a relation: x i <x<x i+1 y i <y<y i+1 It is necessary to (x) i y i ), (x i+1 y i+1 Interpolation is performed between two points. When the time interval between adjacent sampling points is short, a linear function is used for interpolation directly.
[0057]
[0058] Formula (1) yields a linear function y = kx + b containing the target position (x, y). y represents the target amplitude value (30%, 50%, or 90% of the peak value), which can be accurately calculated from the peak value. Substituting y into the formula, the interpolation result x can be obtained, as shown below. Figure 8 As shown.
[0059] In step S600, the peak value, wavefront time, and duration are measured and calculated based on the sampling points and interpolation points.
[0060] Finally, in step S700, the measurement results are displayed.
[0061] This invention also provides an automatic measurement device for lightning surge pulse parameters. The device includes a sampling device and a processor, with the sampling device signal-connected to the processor.
[0062] The sampling device is configured to: acquire pulse waveform data groups and transmit them to the processor;
[0063] The processor is configured to: acquire a pulse waveform data set, the pulse waveform data set including actual acquired sampling points, the sampling points containing time and amplitude parameters; filter the data of the sampling points; extract the pulse parameter measurement-related parts from the filtered sampling point data, remove useless sampling points, and obtain the effective pulse part; based on the effective pulse part, split the effective pulse part into rising edge and falling edge, with the maximum peak value of the pulse waveform as the boundary or the minimum peak value of the pulse waveform as the boundary; interpolate between the sampling points on both sides of the target point required for pulse parameter measurement; and measure and calculate the peak value, wavefront time, and duration based on the sampling points and interpolation points.
[0064] It is important to note that a processor can be a processing device that includes more than one general-purpose processing device, such as a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), etc. More specifically, a processor can be a Complex Instruction Set Computing (CISC) microprocessor, a Reduced Instruction Set Computing (RISC) microprocessor, a Very Long Instruction Word (VLIW) microprocessor, a processor that runs other instruction sets, or a processor that runs a combination of instruction sets. A processor can also be one or more special-purpose processing devices, such as an Application-Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), a Digital Signal Processor (DSP), a System-on-a-Chip (SoC), etc.
[0065] In this embodiment of the invention, the sampling device mainly consists of an FPGA control core, signal acquisition and conditioning, analog-to-digital conversion, digital-to-analog conversion, data processing, and display components, with the timing controlled by an FPGA state machine. Figure 9 and Figure 10 As shown, the FPGA state machine is divided into four states: initialization state idle (s0), ADC start state start (s1), waiting for ADC conversion to finish state ready (s2), and conversion data reading state read (s3). Among them, s1 to s3 change with the clock, and s4 is triggered by a signal.
[0066] The sampling device achieves sampling through the following steps:
[0067] 1. After the FPGA completes initialization, the signal under test enters the acquisition channel and then enters the anti-aliasing filter to filter out the higher frequency part of the "undersampled" signal.
[0068] 2. Analog voltage signals are converted into digital signals via analog-to-digital conversion for DSP processing.
[0069] 3. After data processing is complete, a signal is sent to the control core to indicate that signal processing is complete, and the signal is then displayed by the FPGA.
[0070] It should be noted that the embodiments of the present invention are merely an exemplary sampling method, including but not limited to the sampling method using the sampling device described above.
[0071] In some embodiments, the data of the sampling points are filtered. Before and after filtering, the total number of sampling points remains unchanged, and the sampling order of each sampling point remains unchanged.
[0072] In some embodiments, the data of the sampling points are filtered by the following method: extracting the amplitude data group Y of each sampling point in the pulse waveform data group, represented as Y = {y i}, i = 0, 1, 2, ..., n-1; obtain the filtered amplitude data set Y' using the following equation: y i=Median(J) i ),i=0,1,2,…,n-1,J i ={y i–rl ,y i–rl+1 ,…,y i–1 ,y i ,y i+1 ,…,y i+rr–1 ,y i+rr}, where y i ' is an element of the filtered amplitude data group Y'; J i For the amplitude data group Y at each sampling point, the i-th element y i The nearest neighbor subset centered at y; rl is y i Number of elements on the left; rr is y i Number of elements on the right.
[0073] In some embodiments, extracting the portion of pulse parameter measurement-related data from the filtered sampling points, removing useless sampling points, and obtaining the effective portion of the pulse includes: filtering the amplitude values of the sampling points, retaining sampling points with amplitudes greater than 1% of the peak values, and obtaining the effective portion of the pulse.
[0074] In some embodiments, the step of splitting the effective pulse portion into rising and falling edges based on the maximum peak value of the pulse waveform includes: extracting three feature sampling points of the effective pulse portion, wherein the three feature sampling points are the starting point (x0, y0) and the maximum value (x0, y0) of the effective pulse waveform array, respectively. p y p ) and endpoint (x) n-1 y n-1 ); Split to obtain two new arrays, with the rising edge of array D1 = (x i y i ), i = 0, 1, 2, ..., p; falling edge array D2 = (x i’ y i’ ), i'=p+1, p+2, p+3,..., n-1.
[0075] In some embodiments, interpolation is performed between sampling points on both sides of the target point required for pulse parameter measurement, including: scanning the monotonically ascending rising edge array D1 or falling edge array D2 point by point; when the target point (x, y) is in array D1 or array D2, there exists y = y i The interpolation function outputs the corresponding time x at this moment. i When the target position (x, y) is not in array D1 or array D2, the following relationship exists: x i <x<x i+1 y i <y<yi+1 Using the following formula (1) in (x i y i ), (x i+1 y i+1 Interpolation is performed between two points:
[0076]
[0077] Using the formula (1), a linear function y = kx + b containing the target position (x, y) is obtained, where y is the target value of the amplitude, which is accurately calculated through the peak value. Substituting y into the formula y = kx + b, the interpolation result x can be obtained.
[0078] In some embodiments, the target points include points at 30%, 50%, and 90% of the rising edge peak value and a point at 50% of the falling edge peak value.
[0079] The technical effects and methods of the automatic measurement device for lightning surge pulse parameters described in this embodiment of the invention are basically the same, and will not be repeated here.
[0080] This invention also provides a computer-readable storage medium storing computer-readable instructions that, when executed by a computer's processor, enable the computer to perform any of the methods described in this invention.
[0081] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.
Claims
1. An automatic measurement method for lightning surge pulse parameters, characterized in that, Includes the following steps: Acquire a pulse waveform data set, which includes actual acquired sampling points, and the sampling points contain time and amplitude parameters; The data from the sampling points are then filtered. Extract the pulse parameter measurement-related parts from the filtered sampling data, remove useless sampling points, and obtain the effective pulse part; Based on the effective portion of the pulse, the effective portion of the pulse waveform is divided into rising edge and falling edge, with the maximum peak value of the pulse waveform as the boundary or the minimum peak value of the pulse waveform as the boundary; Based on the pulse parameters, the target point needs to be measured, and interpolation is performed between the sampling points on both sides of it; The peak value, wavefront time, and duration are measured and calculated based on the sampling points and interpolation points. The data from the sampling points are filtered using the following method: Extract the amplitude data group Y of each sampling point in the pulse waveform data group, denoted as Y={ y i },i=0,1,2,…,n-1; The filtered amplitude data set Y' is obtained using the following equation: y i '=Median( J i ),i=0,1,2,…,n-1, J i ={ y i–rl , y i–rl+1 ,…, y i–1 , y i , y i+1 ,…, y i+rr– 1 , y i+rr }， In the formula, y i ' is an element of the filtered amplitude data group Y'; J i For the amplitude data group Y at each sampling point, the i-th element y i A subset of the nearest neighbor array centered on the center; rl for y i Number of elements on the left; rr for y i Number of elements on the right; The step of dividing the effective portion of the pulse into rising and falling edges, based on the maximum peak value of the pulse waveform, includes: Three feature sampling points are extracted from the effective portion of the pulse. These three feature sampling points are the starting point of the effective pulse waveform array (…). x 0, y 0), maximum value ( x p , y p ) and end point ( x n-1 , y n-1 ); Split to get two new arrays, with array D1 = ( x i , y i ), i=0,1,2,...,p; falling edge array D2=( x i’ , y i’ ), i'=p+1, p+2, p+3,..., n-1; Based on the pulse parameters, the target point needs to be measured, and interpolation is performed between the sampling points on both sides of it, including: Scan the monotonically ascending array D1 or the falling array D2 point by point; When the target point ( x , y When it is in array D1 or array D2, it exists y = y i The interpolation function outputs the corresponding time at this point. x i ; When the target location ( x , y If the expression is not in array D1 or D2, the following relationship exists: x i < x < x i+1 , y i < y < y i+1 Using the following formula (1) in ( x i , y i ), ( x i+1 , y i+1 Interpolation between two points: （1） Using the formula (1), the target location is obtained. x , y A linear function y = kx + b ,in y The target value for the amplitude is obtained through accurate calculation of the peak value. y Substitute into the formula y = kx + b The interpolation result can be obtained. x ; Extract the pulse parameter measurement-related parts from the filtered sampled data, remove useless sampled points, and obtain the effective pulse part, including: By filtering the amplitude values of the sampling points, 1% of the sampling points with amplitudes greater than the peak value are retained to obtain the effective portion of the pulse; The target points include the points at 30%, 50%, and 90% of the rising edge peak value and the point at 50% of the falling edge peak value. The sampling device acquires pulse waveform data sets. The sampling device includes a core controller, an anti-aliasing filter, an analog-to-digital converter, a digital-to-analog converter, a data processor, and a display. The core controller controls the timing sequence, which includes four states: initialization state s0, ADC start state s1, waiting for ADC conversion to end state s2, and conversion data reading state s3. Among them, s0~s2 change with the clock, and s3 is triggered by a signal. After the signal under test enters the acquisition channel, it enters the anti-aliasing filter and is converted into a digital signal by the analog-to-digital converter before being output to the data processor for processing. After data processing is completed, the data processor sends a signal to the core controller to indicate that signal processing is complete, and the core controller then sends the signal to the display for display.
2. The method according to claim 1, characterized in that, The data from the sampling points are filtered. Before and after filtering, the total number of sampling points remains unchanged, and the sampling order of each sampling point remains unchanged.
3. An automatic measurement device for lightning surge pulse parameters, based on the method described in any one of claims 1-2, characterized in that, It includes a sampling device and a processor, wherein the sampling device is signal-connected to the processor; The sampling device is configured to: acquire pulse waveform data groups and transmit them to the processor; The processor is configured to: acquire a pulse waveform data set, the pulse waveform data set including actual acquired sampling points, the sampling points including time and amplitude parameters; The data from the sampling points are then filtered. Extract the pulse parameter measurement-related parts from the filtered sampling data, remove useless sampling points, and obtain the effective pulse part; Based on the effective portion of the pulse, the effective portion of the pulse waveform is divided into rising edge and falling edge, with the maximum peak value of the pulse waveform as the boundary or the minimum peak value of the pulse waveform as the boundary; Based on the pulse parameters, the target point needs to be measured, and interpolation is performed between the sampling points on both sides of it; The peak value, wavefront time, and duration are measured and calculated based on the sampling points and interpolation points.
4. A computer-readable storage medium, characterized in that, It stores computer-readable instructions that, when executed by the processor of a computer, cause the computer to perform the method described in any one of claims 1-2.