High-voltage pulse calibration method and system based on distributed deployment

Abstract

The embodiment of the invention discloses a high-voltage pulse calibration method and system based on distributed deployment, and relates to the technical field of high-voltage pulse measurement, and the method comprises the steps: determining the stage number of an optimal voltage divider and a corresponding optimal voltage divider combination based on a target measurement voltage, the total number of distributed small voltage dividers, the maximum output voltage and an uncertainty parameter; each voltage generation module of the all-solid-state multi-stage voltage generator is correspondingly connected with one distributed small voltage divider; the distributed small voltage divider corresponding to the optimal voltage divider combination is started to measure the voltage of the corresponding voltage generation module, and the measured voltage of each level of voltage divider is obtained; calibrating the measured voltage of each level of voltage divider and the corresponding standard source to obtain each level of calibration coefficient; correcting each level of voltage divider measurement voltage by using each level of calibration coefficient to obtain each level of corrected measurement voltage; based on each level of corrected measurement voltage, an overall output voltage signal is obtained, and the problem of low high-voltage pulse measurement precision of an all-solid-state multi-level pulse voltage generator is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high-voltage pulse measurement, in particular to a high-voltage pulse calibration method and system based on distributed deployment. BACKGROUND

[0002] A full-solid multi-stage pulse voltage generator is a device capable of generating high-voltage pulses, which has wide application prospects in industries, scientific research, medical treatment and other fields. However, the high-voltage pulses generated by the full-solid multi-stage pulse voltage generator have the characteristics of large amplitude (up to hundreds of kilovolts or even higher) and fast rising time (nanosecond level), and the internal circuits of the full-solid multi-stage pulse voltage generator are complex in distribution. The traditional centralized measurement system cannot meet the demand for real-time and accurate measurement of high-voltage pulses.

[0003] The traditional high-voltage pulse measurement method usually adopts a single high-voltage divider to directly measure the overall voltage, but this method has the following problems: 1. The frequency response characteristics of the high-voltage divider are difficult to meet the measurement demand of the fast rising edge, resulting in waveform distortion; 2. The influence of distributed parameters (such as parasitic capacitance and inductance) is significant, further reducing the measurement accuracy; 3. The electromagnetic interference in the high-voltage environment is serious, affecting the quality of the measurement signal; 4. The division ratio of the single divider is fixed, and it is difficult to meet the requirements of large-range voltage amplitude and high-precision measurement at the same time.

[0004] The above reasons can all lead to a decrease in the accuracy of the measurement results, which will be difficult to meet the technical index requirements of various fields in the future.

[0005] Therefore, a new high-voltage pulse calibration system is needed to effectively solve the problem of low measurement accuracy of high-voltage pulses of the full-solid multi-stage pulse voltage generator. SUMMARY

[0006] The present specification provides a high-voltage pulse calibration system and method based on distributed deployment to solve the problem of low measurement accuracy of high-voltage pulses of the full-solid multi-stage pulse voltage generator. To achieve the above purpose, the technical solution adopted by the present specification is as follows: In one aspect, the present specification provides a high-voltage pulse calibration method based on distributed deployment, which comprises: Step 102, based on the target measurement voltage, the total number of distributed small dividers, the maximum output voltage and the uncertainty parameter, determining the optimal divider order and the corresponding optimal divider combination; each voltage generation module of the full-solid multi-stage voltage generator is connected to a distributed small divider. Step 104, start the optimal voltage divider combination corresponding to the distributed small voltage divider to measure the voltage of the corresponding voltage generating module, and obtain the measured voltage of each stage voltage divider; Step 106, calibrate the measured voltage of each stage voltage divider with the corresponding standard source, and obtain the calibration coefficient of each stage; Step 108, correct the measured voltage of each stage voltage divider using the calibration coefficient of each stage, and obtain the corrected measured voltage of each stage; Step 110, based on the corrected measured voltage of each stage, obtain the overall output voltage signal.

[0007] On the other hand, the present specification provides a high-voltage pulse calibration system based on distributed deployment, which comprises: A distributed small voltage divider is used to calibrate the voltage of each voltage generating module of the all-solid-state multi-stage pulse voltage generator and obtain a voltage divider measured voltage; the distributed small voltage divider is composed of patch resistors in series according to a target voltage division ratio; A high-speed analog-to-digital converter is used to convert the voltage divider measured voltage output by the distributed small voltage divider into a digital signal, generate a measured voltage signal of each stage, and transmit it to an upper computer; A timing control module is used to provide a unified clock signal for each high-speed analog-to-digital converter; An upper computer is used to process and evaluate the waveform quality of the received measured voltage signal of each stage, and obtain the overall output voltage signal and waveform quality evaluation result of the all-solid-state multi-stage pulse voltage generator; The upper computer comprises: A waveform reconstruction module is used to combine and reconstruct the waveform of the received measured voltage signal of each stage, and obtain the overall output voltage signal of the all-solid-state multi-stage pulse voltage generator; A waveform quality evaluation module is used to evaluate the quality of the reconstructed overall output voltage signal and obtain the waveform quality evaluation result.

[0008] Based on the above technical solution, the present specification can achieve the following technical effects: The present method deploys a distributed voltage acquisition device in each module of the all-solid-state multi-stage pulse voltage generator, transmits the acquired voltage signal to the upper computer for integration through a distributed acquisition network, and calibrates each voltage module with a standard source, thereby achieving higher accuracy in measuring and calibrating high-voltage pulses, and solving the problem of low accuracy in measuring high-voltage pulses of the all-solid-state multi-stage pulse voltage generator. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a flowchart of a high-voltage pulse calibration method based on distributed deployment according to an embodiment of the present specification.

[0010] FIG. 2 is a diagram illustrating the weight of each frequency and the standard calibration according to an embodiment of the present specification.

[0011] Figure 3 FIG. 3 is a diagram illustrating a workflow of a high-voltage pulse calibration system based on distributed deployment according to an embodiment of the present specification.

[0012] Figure 4 FIG. 4 is a diagram illustrating a circuit topology of an all-solid-state multi-stage pulse voltage generator and a distributed sampling according to an embodiment of the present specification.

[0013] Figure 5 FIG. 5 is a diagram illustrating a flowchart of a host computer according to an embodiment of the present specification. DETAILED DESCRIPTION

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present specification, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some examples or embodiments of the present specification, and for those skilled in the art, the present specification can also be applied to other similar scenarios without creative labor. Unless it is clear from the language context or otherwise indicated, the same reference numbers in the drawings represent the same structure or operation.

[0015] It should be understood that the "system", "device", "unit" and / or "module" used in the present specification is a method for distinguishing different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, the words can be replaced by other expressions.

[0016] As shown in the present specification and claims, unless the context clearly indicates otherwise, the words "one", "a", "an" and / or "the" do not refer to the singular, but can also include the plural. Generally speaking, the terms "comprise" and "include" only indicate the inclusion of the steps and elements explicitly identified, and these steps and elements do not constitute an exclusive list, and the method or device can also include other steps or elements.

[0017] Flowcharts are used in the present specification to illustrate the operations performed by the system according to the embodiments of the present specification. It should be understood that the preceding or subsequent operations do not necessarily have to be performed in sequence. Instead, the steps can be processed in reverse order or simultaneously. At the same time, other operations can also be added to these processes, or one or more steps of the operation can be removed from these processes.

[0018] Embodiment 1 Please refer to Figure 1 , Figure 1A flowchart of a high-voltage pulse calibration method based on distributed deployment provided by the embodiment is shown. The method comprises the following steps: In step 102, based on the target measurement voltage, the total number of distributed small dividers, the maximum output voltage, and the uncertainty parameter, the optimal divider order and the corresponding optimal divider combination are determined; each voltage generation module of the all-solid-state multi-stage voltage generator is connected to a distributed small divider; In the embodiment, before step 102, the following steps are further included: In step 101, a high-precision standard voltage source is used to calibrate each distributed small divider at different voltage levels to obtain the uncertainty parameter of each distributed small divider at different voltage levels.

[0019] In the embodiment, one implementation of step 101 is as follows: In step 202, a high-precision standard voltage source is used to measure the voltage of each distributed small divider at different voltage levels to obtain the measured voltage value; In step 204, the measured voltage value is compared with the voltage indication value of the high-precision standard voltage source to obtain the voltage deviation data; In step 206, the measurement uncertainty is calculated based on the voltage deviation data obtained from several measurements; in step 208, the uncertainty parameter of each distributed small divider at different voltage levels is calculated based on the measurement uncertainty and the standard uncertainty of the high-precision standard voltage source; In step 210, based on the linearity difference caused by the difference in device process, the linear interpolation method is used to interpolate the voltage deviation data to obtain the linearity error statistical table.

[0020] Specifically, for each divider module, a high-precision standard voltage source is used to select multiple different voltage levels within its working voltage range for measurement. The measured voltage value of the divider at each voltage level is obtained by the measurement equipment, and compared with the voltage indication value output by the standard voltage source to obtain the voltage deviation data at each voltage level; Based on the variance of the voltage deviation data obtained from several measurements, the measurement uncertainty is calculated; according to the measurement uncertainty at a specific voltage level and the standard uncertainty of the high-precision standard voltage source, the uncertainty parameter of each divider at the specific voltage level is calculated to form the basic data support for subsequent optimal order selection.

[0021] Based on the slight change in linearity caused by the difference in device process, the linear interpolation method is used to interpolate and fill the voltage deviation data to establish a linearity error statistical table for subsequent voltage correction; The formula for calculating the uncertainty parameter is as follows: ​

[0022] wherein, represents the measurement uncertainty at a certain voltage level; represents the standard uncertainty of the high-precision standard voltage source at a certain voltage level; In this embodiment, one implementation of step 102 is: Step 302, based on the target measurement voltage and the maximum output voltage of the distributed small voltage divider, calculate the minimum divider order; Step 304, traverse from the total number of distributed small voltage dividers to the minimum divider order: Step 306, for each traversed divider order, based on the target measurement voltage and the current divider order, calculate the current voltage level; Step 308, based on the current voltage level, determine the uncertainty parameter of each distributed small voltage divider at the current voltage level, and select the target distributed small voltage divider whose uncertainty parameter is lower than the preset threshold; Step 310, based on the uncertainty parameter of the target distributed small voltage divider at the current voltage level, calculate the combined measurement uncertainty after the target distributed small voltage divider is connected in series at the current divider order; Step 312, select the divider order with the smallest combined measurement uncertainty as the optimal divider order, and determine the optimal divider combination corresponding to the optimal divider order.

[0023] Specifically, the optimal working module order selection (taking the measurement of a 75kV target voltage as an example), the total number of modules is N, the target voltage is V target =75kV. The maximum output voltage of a single module is determined (which can be obtained from the module parameters, and is assumed to be V m ), the minimum order n min is calculated, i.e. n min =V target / V m (rounded up). n is the possible order (n is an integer and satisfies n min ).

[0024] For each traversed order n, calculate the voltage V per =V target / n required for each level, select the voltage divider module whose uncertainty is lower than the preset threshold at the voltage level V per , and exclude the order with larger uncertainty. For the n-level voltage divider after screening, based on the uncertainty parameters u (u i is the measurement uncertainty of the i-th level voltage divider at the corresponding voltage level) of each voltage divider at the corresponding voltage level, the combined measurement uncertainty after connection in series is calculated by the formula.

[0025]

[0026] n from N to n min The measurement precision of the output voltage is ensured to be optimal by driving the corresponding module to discharge and work according to the final working stage number selected from the stage number combinations with the minimum combined uncertainty.

[0027] In step 104, the corresponding distributed small voltage divider of the optimal voltage divider combination is started to measure the voltage of the corresponding voltage generating module, and the measured voltage of each stage of voltage divider is obtained. In step 106, the measured voltage of each stage of voltage divider is calibrated with the corresponding standard source, and the calibration coefficient of each stage is obtained. In the embodiment, one implementation of step 106 is as follows: In step 402, the voltage time domain signal and the standard source time domain signal are obtained based on the measured voltage of each stage of voltage divider and the standard source. In step 404, the voltage frequency domain signal and the standard source frequency domain signal are obtained by performing fast Fourier transform on the voltage time domain signal and the standard source time domain signal respectively. In step 406, the calibration coefficient of each stage of voltage divider is obtained by comparing the voltage frequency domain signal with the standard source frequency domain signal.

[0028] In the embodiment, the calibration coefficient includes the amplitude calibration coefficient and the phase calibration coefficient. In the embodiment, one implementation of step 404 is as follows: In step 4041, the voltage frequency domain signal and the standard source frequency domain signal under different frequency groups are obtained by grouping the frequency of the voltage frequency domain signal and the standard source frequency domain signal. In step 4042, the voltage component amplitude and the standard source component amplitude of each group are obtained by taking the modulus value of the voltage frequency domain signal and the standard source frequency domain signal in each group. In step 4043, the amplitude calibration coefficient of each voltage divider under different frequencies is calculated and obtained based on the voltage component amplitude and the standard source component amplitude. In step 4044, the phase calibration coefficient of each voltage divider under different frequencies is calculated and obtained based on the phase of the sine signal of the voltage frequency domain signal and the standard source frequency domain signal under different frequency groups.

[0029] Specifically, when each stage of output voltage is calibrated with the standard source, the time domain waveform signal y(t) of each stage of voltage divider after reconstruction is collected. The fast Fourier transform (FFT) is introduced to y(t), and the formula is as follows:

[0030] Wherein N is the number of sampling points, j = 0, 1,..., N-1, the time domain signal is converted into the frequency domain signal Y(j). By analyzing Y(j), the frequency domain decomposition results of the measured waveform and the standard source waveform are compared, and the correction coefficient k is introduced f The phases and amplitudes of the measured signals at different frequencies are calibrated, and the correction coefficient set of each stage is recorded. In actual measurement, the recorded correction coefficient set of each stage is used to correct the measured signal before reconstructing the waveform, so that more accurate measurement values are obtained, and the accuracy of voltage measurement is improved.

[0031] The FFT results of the measured waveform Y recon (j) and the standard waveform Y std (j) are grouped according to frequency, and the amplitudes (modulus values |Y(j)|) in each group are compared: The amplitude of the mth frequency component of the measured waveform:

[0032] The amplitude of the mth frequency component of the standard waveform:

[0033] The amplitude calibration coefficient k fm reflects the difference between the measured waveform and the standard waveform at each frequency component. The calculation formula is:

[0034] The phase calibration coefficient k ff The calculation formula is:

[0035] Where θ1 and θ2 are the phases of the sinusoidal signal in the frequency domain.

[0036] Step 108, using the calibration coefficients of each stage to correct the voltage measured by each stage of the voltage divider, to obtain the corrected voltage measured by each stage; In this embodiment, one implementation of step 108 is: Based on the amplitude calibration coefficient and the phase calibration coefficient of each stage of the voltage divider at different frequencies, the voltage measured by each stage of the voltage divider is calibrated at different frequencies, and the corrected voltage measured by each stage is obtained.

[0037] Step 110, based on the corrected voltage measured by each stage, obtaining the overall output voltage signal.

[0038] In this embodiment, one implementation of step 110 is: Step 502, converting the corrected voltage measured by each stage into a corresponding digital signal to obtain the voltage measurement signal of each stage; Step 504, merging the voltage measurement signals of each stage to obtain the overall measurement voltage signal; Step 506, the whole measurement voltage signal is convoluted and reconstructed to obtain a reconstructed whole output voltage signal.

[0039] Specifically, the output voltage of each stage is collected and transmitted into the ADC module to convert the electrical signal into a digital signal, and then imported into the host computer for processing through the multi-channel data acquisition card. The sampling timing control needs to be synchronized with the power discharge timing control.

[0040] The waveform reconstruction method based on convolution operation is adopted. In specific implementation, according to the pulse response characteristics of the system, a suitable convolution kernel is designed. Assuming that the pulse response of the system is h[a], the discrete voltage signal collected by the i th module x i [n] Through the formula:

[0041] Where M is the length of the pulse response h[a]. Through the convolution operation, the signals of each module can be effectively fused to restore the superimposed waveform as a more accurate high-voltage pulse waveform measured; The convolution operation is performed to reconstruct and fuse the signals of each module calibrated by the correction coefficient, and the whole output voltage waveform of the all-solid-state Marx generator is reconstructed.

[0042] In this embodiment, after step 110, it further includes: Step 112, performing fast Fourier transform on the whole output voltage signal to obtain a whole output voltage frequency domain signal; Step 114, calculating the waveform distortion degree based on the whole output voltage frequency domain signal; Step 116, comparing the waveform distortion degree with a preset distortion threshold, and if the waveform distortion degree exceeds the preset distortion threshold, determining that the measurement is abnormal.

[0043] Specifically, when evaluating the quality of the reconstructed waveform, fast Fourier transform (FFT) is introduced to analyze the waveform in the frequency domain. Assuming that the reconstructed time-domain waveform signal is y(n), the frequency domain signal is obtained after FFT transformation:

[0044] Where N is the number of sampling points. K=0,1,...,N-1. Based on the frequency domain signal Y(k), the waveform distortion degree, signal-to-noise ratio and other indicators can be calculated, and the calculation results are compared with the preset threshold. When the indicators exceed the threshold, an alarm signal is sent to check the potential problems of the power supply in time. The specific process is as follows: The frequency point k after FFT decomposition corresponds to the actual frequency f k =k•fs / N, but due to the symmetry of the FFT result (the first half of the FFT result of the real signal is the positive frequency, and the second half is the negative frequency mirror), usually only the first N / 2+1 points are taken for analysis. For periodic waveforms (such as sine wave, square wave), the frequency components are mostly integer multiples of the fundamental frequency (harmonics). In order to accurately evaluate the accuracy of the measured signal, the FFT results of the reconstructed waveform and the standard waveform should be grouped according to the same frequency interval and compared.

[0045] The FFT results of the reconstructed waveform Y recon (k) and the standard waveform Y std (k) are grouped by frequency and the amplitudes in each group are added (taking the modulus value |Y(k)|) to obtain the integrated frequency domain amplitude: The amplitude of the wth frequency component of the reconstructed waveform:

[0046] The amplitude of the wth frequency component of the standard waveform:

[0047] The error rate formula reflecting the difference between the reconstructed waveform and the standard waveform at each frequency component is:

[0048] As shown in Figure 2 , taking a square wave as an example, after fft decomposition, the proportion of each frequency component in the frequency domain can be obtained, and the total waveform energy is 1. According to the amplitude of the harmonic waveform at different frequencies, the weight of the error brought by different frequencies is assigned, and the difference between the reconstructed waveform and the standard waveform at each frequency component is reflected. The calculation formula is:

[0049] Where W is the number of frequency groups.

[0050] According to the frequency domain signal, the waveform distortion index is calculated. For example, by calculating the ratio of each harmonic component to the fundamental component, the total harmonic distortion (THD) is obtained, and the calculation formula is:

[0051] The calculation results are compared with the preset threshold value, and when the index exceeds the normal threshold value, the host computer issues a warning, and at this time some modules may appear abnormal.

[0052] In summary, the method realizes higher accuracy measurement and calibration of high-voltage pulses by deploying a distributed voltage acquisition device in each module of the all-solid-state multi-stage pulse voltage generator, transmitting the acquired voltage signals to the host computer for integration through a distributed acquisition network, and calibrating each voltage module with a standard source.

[0053] Embodiment 2 The embodiment provides a high-voltage pulse calibration system based on distributed deployment. The system comprises: A distributed small divider is used to calibrate the voltage of each voltage generation module of the all-solid-state multi-stage pulse voltage generator and obtain a divider measurement voltage; the distributed small divider is composed of patch resistors in series according to a target voltage division ratio; A high-speed analog-to-digital converter is used to convert the divider measurement voltage output by the distributed small divider into a digital signal, generate a measurement voltage signal of each stage, and transmit the signal to the host computer; A timing control module is used to provide a unified clock signal for each high-speed analog-to-digital converter; A host computer is used to perform signal processing and waveform quality evaluation on the received measurement voltage signals of each stage, and obtain an overall output voltage signal of the all-solid-state multi-stage pulse voltage generator and a waveform quality evaluation result; The host computer comprises: A waveform reconstruction module is used to combine and reconstruct the received measurement voltage signals of each stage, and obtain an overall output voltage signal of the all-solid-state multi-stage pulse voltage generator; A waveform quality evaluation module is used to evaluate the quality of the reconstructed overall output voltage signal, and obtain a waveform quality evaluation result.

[0054] In the embodiment, reference Figure 3 is made to the system workflow diagram. The all-solid-state multi-stage pulse voltage generator is composed of a plurality of modules connected in cascade, each module is provided with a distributed small divider, the voltage signal is converted from analog to digital through the corresponding A / D, then the voltage signals of the plurality of modules are collected through the data acquisition card and uploaded to the host computer; due to the distributed deployment, the voltage parameters to be measured of each stage are reduced, so the divider can use low-voltage high-precision patch resistors for voltage division, which can accurately measure the voltage of the corresponding module. Compared with the traditional method of directly measuring the overall voltage by a single high-voltage divider, the distributed measurement reduces the influence of distributed parameters (such as parasitic capacitance and inductance), and the distributed sampling method greatly improves the accuracy of the power signal of each module, effectively overcoming the waveform distortion problem caused by insufficient frequency response characteristics in the traditional measurement method.

[0055] Optionally, in each module of the all-solid-state multi-stage pulse voltage generator, a high-precision voltage-resistant low-voltage patch resistor voltage dividing circuit is installed as a distributed small voltage divider. The patch resistors are connected in series according to a specific voltage dividing ratio, and a 100MΩ and 100kΩ resistor series connection is adopted to achieve 1000:1 voltage division of the module output voltage, ensuring that the voltage input to the subsequent measurement circuit is within a safe and measurable range.

[0056] Reference Figure 4 The distributed small voltage divider is connected in parallel across the main capacitor Cn, collects the output voltage of each stage and transmits it into the ADC module to convert the electrical signal into a digital signal, and then imports the data into the host computer through a multi-channel data acquisition card for processing. The sampling time sequence control needs to be synchronized with the power discharge time sequence control.

[0057] In this embodiment, a high-speed analog-to-digital converter (ADC) is deployed in each module to convert the voltage signal collected by the voltage divider into a digital signal. An ADC chip with a resolution of 14 bits and a sampling rate of 200MSPS (AD9250 of ADI Company) can be selected to meet the collection requirements of high-voltage pulses with rapid changes.

[0058] Optionally, the ADC chip is connected to the subsequent data processing unit through an SPI interface, the transmission protocol uses differential signal encoding, and the LVDS (Low Voltage Differential Signal) technology is used for data transmission to effectively enhance the anti-interference capability. When laying out the PCB, the SPI data lines are processed to be equal in length, and a shielding layer is added to further ensure the accuracy of data transmission.

[0059] Optionally, in order to meet the requirements of high sampling rate and response speed, a high-speed parallel interface is used for data transmission, the transmission protocol uses differential signal encoding, and the anti-interference capability is enhanced to ensure that the quality of the measured signal is not affected by serious electromagnetic interference in a high-voltage environment.

[0060] Optionally, a timing control unit is provided, which is based on FPGA and can accurately control the sampling start time and sampling frequency of each module ADC, ensuring that the sampling data of all modules is based on the same time axis. This provides an accurate timing basis for subsequent waveform reconstruction.

[0061] Optionally, an FPGA chip from Xilinx Company is used as the core of the timing control unit, and a program written in Python language is used to realize the accurate timing control logic. A clock management module is designed inside the FPGA to generate a stable clock signal as the sampling clock of each module ADC. By configuring the GPIO port of the FPGA, accurate sampling start time and sampling frequency control signals are output to ensure that the sampling data of all modules is based on the same time axis, and the sampling clock jitter is controlled within ±1ns.

[0062] Optionally, in the system initialization phase, each module is self-diagnosed by the self-checking unit. The self-checking program is written to sequentially detect whether the resistance value of the distributed voltage divider is normal, whether the sampling function of the ADC is accurate, etc.

[0063] Optionally, if a fault is detected in a certain module, the host computer displays the location and type of the faulty module and prompts on the system interface, facilitating maintenance personnel to quickly locate and handle the problem.

[0064] Optionally, the system calibration and test the voltage divider calibration, using a high-precision voltage standard source (such as FLUKE 5720A) to calibrate the distributed voltage divider, apply different voltage values output by the standard source to the input of the voltage divider, measure the output voltage of the voltage divider, and compare it with the theoretical calculation value. According to the measurement error, the resistance value of the voltage divider is fine-tuned to ensure that the voltage division ratio error of the voltage divider is controlled within ±1%.

[0065] Optionally, reference Figure 5 For each voltage divider module, a high-precision standard voltage source is used to select multiple different voltage levels within its operating voltage range for measurement. Through the measurement device, the measured voltage value of the voltage divider at each voltage level is obtained, compared with the voltage indication value output by the standard voltage source, and the voltage deviation data at each voltage level is obtained; then based on the slight changes in linearity caused by device process differences, linear interpolation is used to interpolate and fill the voltage deviation data, and a linearity error statistical table is established; according to a specific voltage level, the target voltage deviation in the linearity error statistical table is extracted, and then the voltage indication value of the high-precision standard voltage source at this voltage level is used to calculate the measurement uncertainty parameter of each voltage divider at the specific voltage level, forming the basis data to support subsequent optimal order selection.

[0066] At the same time, the amplitude and phase of each voltage divider are calibrated at different frequencies by a sinusoidal sweep method (the scan termination frequency is not less than 2MHz) with a legally mandated or authorized calibration voltage divider, and the amplitude-frequency characteristic, phase-frequency characteristic parameter or curve obtained and recorded.

[0067] When the target voltage to be measured by the test sample is 75kV (for example, 75kV Note: if the maximum output voltage of the full-solid-state multi-stage pulse voltage generator is 200kV, the capability interval is higher than the target voltage), based on the principle of parallel charging and series discharging, the optimal working module order is selected by the following steps: Order traversal selection calculation: for the possible order n (n is an integer and satisfies n≤module total number N), calculate the voltage required by each stage as V per =V target / n, according to the pre-calibrated linearity error statistical table, select the voltage level V perThe partial pressure module with a lower measurement uncertainty than the preset threshold is excluded from the series with a larger uncertainty; for the screened n-stage partial pressure module, the combined measurement uncertainty after series connection is calculated based on the uncertainty parameters of each partial pressure module at the corresponding voltage level, and the calculation formula is:

[0068] where u i is the measurement uncertainty of the i-th stage partial pressure module at the corresponding voltage level After n-stage combination from N to the minimum number of stages (target voltage / single module maximum output, rounded up), the corresponding combined uncertainty is calculated, and the stage combination with the smallest combined uncertainty is selected as the final working stage number to drive the corresponding module to discharge and work, so as to ensure the optimal measurement accuracy of the output voltage.

[0069] Further, as shown in the host computer program diagram Figure 4 , the host computer performs sinusoidal sweep calibration. When each stage output voltage is calibrated with the standard source, fast Fourier transform (FFT) is introduced to analyze the sinusoidal sweep calibration of the waveform. Assuming that the reconstructed time domain waveform signal is y(t), the frequency domain signal is obtained after FFT transform:

[0070] where N is the number of sampling points. j=0,1,...,N-1. Based on the amplitude-frequency characteristic, phase-frequency characteristic parameter or curve of the aforementioned sinusoidal sweep calibration, the correction coefficient k f can be introduced according to the frequency domain decomposition Y(j) of the measurement waveform and the standard source waveform, the phase and amplitude of the measurement signal at different frequencies are calibrated, and the correction coefficient set of each stage is recorded. After correction, the waveform is reconstructed to obtain a more accurate measurement value.

[0071] The beneficial effects brought by the technical solution are as follows: 1. Distributed multi-node collaborative calibration is adopted, combined with high-precision time synchronization (such as PTP protocol), so that the overall calibration accuracy of the system reaches within ±0.1%, which is better than the traditional centralized calibration method (usually ±0.5%).

[0072] 2. Modular design allows calibration nodes to be added or reduced as needed to adapt to different scales of high-voltage pulse testing requirements (such as from small-scale laboratory to industrial-scale applications).

[0073] Based on this, the system deploys a distributed voltage acquisition device in each module of the all-solid-state multi-stage pulse voltage generator, and then transmits the acquired voltage signals to the host computer through the distributed acquisition network for integration. At the same time, each voltage module is calibrated with a standard source, thereby realizing higher accuracy measurement and calibration of high-voltage pulses.

[0074] In summary, the system effectively solves the problem of low precision of full solid-state Marx generator high-voltage pulse measurement by means of distributed deployment, high-speed ADC, accurate timing control, waveform reconstruction and quality evaluation, and can meet the technical index requirements of high-voltage pulse accurate measurement in multiple fields such as industry, scientific research and medical treatment.

[0075] It should be noted that different embodiments can have different beneficial effects, and in different embodiments, the beneficial effects that can be produced can be any one or a combination of the above, or any other beneficial effects that can be obtained.

[0076] The foregoing has described the basic concepts, and it is obvious that the above detailed disclosure is only used as an example and does not constitute a limitation on the present specification. Although it is not explicitly stated here, those skilled in the art can make various modifications, improvements and corrections to the present specification. Such modifications, improvements and corrections are suggested in the present specification, so such modifications, improvements and corrections still belong to the spirit and scope of the exemplary embodiments of the present specification.

[0077] At the same time, the present specification uses specific words to describe the embodiments of the present specification. As "one embodiment", "an embodiment", and / or "some embodiments" means a certain feature, structure or characteristic related to at least one embodiment of the present specification. Therefore, it should be emphasized and noted that the "an embodiment" or "one embodiment" or "one alternative embodiment" mentioned in different places in the present specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present specification can be properly combined.

[0078] In addition, those skilled in the art can understand that aspects of the present specification can be described and claimed in a number of patentable aspects or claims, including any new and useful processes, machines, products or compositions of matter, or any new and useful improvements thereof. Accordingly, the various aspects of the present specification can be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software can be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". In addition, aspects of the present specification can be manifested as computer products located in one or more computer readable media, including computer readable program codes.

[0079] Computer storage media can include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program code, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, solid state drives (SSDs), flash memory, phase-change memory ("PCM"), other types of memory, other types of storage medium, or any suitable combination thereof. Computer storage media can be embedded in a computer system, for example, as system memory or system storage, or provided externally to the computer system, for example, as a removable memory drive or other storage device.

[0080] It should be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to "a component" or "the component" can include a combination of two or more components, and the like.

[0081] Some embodiments use numerals to describe components, quantities of attributes. It should be understood that such numerals used in the description of embodiments can in some examples be modified by the adjectives "about," "approximately," or "substantially." Unless otherwise indicated, "about," "approximately," or "substantially" indicates that the described dimension allows for ±20% variation. Accordingly, numerical parameters such as those outlined in the specification and claims are approximations, and can vary depending upon the desired properties sought to be obtained by the particular embodiment. In some embodiments, numerical parameters are determined by the use of standard techniques. Although the numerical ranges and parameters setting forth the broad scope of the embodiments are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, can contain certain errors associated with testing measurements.

[0082] Finally, it should be understood that the embodiments described herein are intended to be illustrative only and that the scope of the present specification is not intended to be limited to the embodiments described herein. Rather, the scope of the present specification is intended to cover all alternatives, modifications, and equivalents falling within the scope of the present specification. Accordingly, alternative configurations of the embodiments described herein are considered to be within the scope of the present specification.

Claims

1. A high-voltage pulse calibration method based on distributed deployment, characterized in that, The method comprises the following steps: Based on the target measurement voltage, the total number of distributed small voltage dividers, the maximum output voltage, and the uncertainty parameter, determine the optimal number of voltage dividers and the corresponding optimal voltage divider combination; each voltage generation module of the all-solid-state multi-stage voltage generator is connected to a distributed small voltage divider; Start the distributed small voltage divider corresponding to the optimal voltage divider combination, measure the voltage of the corresponding voltage generation module, and obtain the measurement voltage of each stage of voltage divider; Calibrate the measurement voltage of each stage of voltage divider with the corresponding standard source to obtain the calibration coefficient of each stage; Use the calibration coefficient of each stage to correct the measurement voltage of each stage of voltage divider to obtain the corrected measurement voltage of each stage; Based on the corrected measurement voltage of each stage, obtain the overall output voltage signal.

2. The method of claim 1, wherein, Before the step of determining the optimal number of voltage dividers and the corresponding optimal voltage divider combination based on the target measurement voltage, the total number of distributed small voltage dividers, the maximum output voltage, and the uncertainty parameter, the method further comprises the following steps: Calibrate each distributed small voltage divider at different voltage levels using a high-precision standard voltage source to obtain the uncertainty parameter and the linearity error statistical table of each distributed small voltage divider at different voltage levels.

3. The method of claim 2, wherein, The step of calibrating each distributed small voltage divider at different voltage levels using a high-precision standard voltage source to obtain the uncertainty parameter and the linearity error statistical table of each distributed small voltage divider at different voltage levels comprises the following steps: Measure the voltage of each distributed small voltage divider at different voltage levels using a high-precision standard voltage source to obtain the measured voltage value; Compare the measured voltage value with the voltage indication value of the high-precision standard voltage source to obtain the voltage deviation data; Based on the voltage deviation data obtained from several measurements, calculate the measurement uncertainty; Based on the measurement uncertainty and the standard uncertainty of the high-precision standard voltage source, calculate the uncertainty parameter of each distributed small voltage divider at different voltage levels; Based on the linearity difference caused by the difference in device technology, use linear interpolation to interpolate the voltage deviation data to obtain the linearity error statistical table.

4. The method of claim 2, wherein, The step of determining the optimal number of voltage dividers and the corresponding optimal voltage divider combination based on the target measurement voltage, the total number of distributed small voltage dividers, the maximum output voltage, and the uncertainty parameter comprises the following steps: Based on the target measurement voltage and the maximum output voltage of the distributed small voltage divider, calculate the minimum number of voltage dividers; From the total number of distributed small voltage dividers to the minimum number of voltage dividers: For each traversed number of voltage dividers, based on the target measurement voltage and the current number of voltage dividers, calculate the current voltage level; Based on the current voltage level, determine the uncertainty parameter of each distributed small voltage divider at the current voltage level, and select the target distributed small voltage divider whose uncertainty parameter is lower than the preset threshold; Based on the uncertainty parameter of the target distributed small voltage divider at the current voltage level, calculate the combined measurement uncertainty after the target distributed small voltage divider is connected in series at the current voltage level; Select the number of voltage dividers with the smallest combined measurement uncertainty as the optimal number of voltage dividers, and determine the optimal voltage divider combination corresponding to the optimal number of voltage dividers.

5. The method of claim 2, wherein, The calibration of the voltage measured by each voltage divider and the corresponding standard source includes: Based on the voltage measured by each voltage divider and the standard source, the corresponding voltage time domain signal and the standard source time domain signal are obtained; The voltage time domain signal and the standard source time domain signal are respectively subjected to fast Fourier transform to obtain the voltage frequency domain signal and the standard source frequency domain signal; The voltage frequency domain signal and the standard source frequency domain signal are compared to obtain the calibration coefficient of each voltage divider.

6. The method of claim 5, wherein, The calibration coefficient includes amplitude calibration coefficient and phase calibration coefficient; the comparison of the voltage frequency domain signal and the standard source frequency domain signal to obtain the calibration coefficient of each voltage divider includes: The voltage frequency domain signal and the standard source frequency domain signal are grouped according to frequency to obtain the voltage frequency domain signal and the standard source frequency domain signal under different frequency groups; The voltage frequency domain signal and the standard source frequency domain signal of each group are taken as a modulus value within the group to obtain the voltage component amplitude and the standard source component amplitude of each group; Based on the voltage component amplitude and the standard source component amplitude, the amplitude calibration coefficient of each voltage divider under different frequencies is calculated and obtained; Based on the phase of the sine signal of the voltage frequency domain signal and the standard source frequency domain signal under different frequency groups, the phase calibration coefficient of each voltage divider under different frequencies is calculated and obtained.

7. The method of claim 6, wherein, The correction of the voltage measured by each voltage divider using the calibration coefficient of each level includes: Based on the linearity error statistical table, the amplitude calibration coefficient and the phase calibration coefficient of each voltage divider under different frequencies are used to calibrate the voltage measured by each voltage divider under different frequencies to obtain the corrected measurement voltage of each level.

8. The method of claim 1, wherein, The obtaining of the overall output voltage signal based on the corrected measurement voltage of each level includes: The corrected measurement voltage of each level is converted into a corresponding digital signal to obtain the measurement voltage signal of each level; The measurement voltage signals of each level are combined to obtain the overall measurement voltage signal; The overall measurement voltage signal is convolved and reconstructed to obtain the reconstructed overall output voltage signal.

9. The method of claim 1, wherein, After the overall output voltage signal is obtained based on the corrected measurement voltage of each level, it further includes: The overall output voltage signal is subjected to fast Fourier transform to obtain the overall output voltage frequency domain signal; Based on the overall output voltage frequency domain signal, the waveform distortion degree is calculated and obtained; The waveform distortion degree is compared with the preset distortion threshold value, and if the waveform distortion degree exceeds the preset distortion threshold value, it is determined that the measurement is abnormal.

10. A distributed deployment based high voltage pulse calibration system suitable for use in the method of claim 1, characterized by, It includes: Distributed small voltage divider, used for calibrating the voltage of each voltage generation module of the all-solid-state multi-stage pulse voltage generator to obtain the voltage divider measurement voltage; The distributed small voltage divider is composed of patch resistors in series according to the target voltage division ratio; High-speed analog-to-digital converter, used for converting the voltage divider measurement voltage output by the distributed small voltage divider into a digital signal, generating the measurement voltage signal of each level and transmitting it to the upper computer; Timing control module, used for providing a unified clock signal for each high-speed analog-to-digital converter; Upper computer, used for signal processing and waveform quality evaluation of the received measurement voltage signal of each level to obtain the overall output voltage signal of the all-solid-state multi-stage pulse voltage generator and the waveform quality evaluation result; The upper computer includes: A waveform reconstruction module is configured to combine and reconstruct the received multi-stage measurement voltage signals to obtain an overall output voltage signal of the all-solid-state multi-stage pulse voltage generator. A waveform quality evaluation module is configured to evaluate the quality of the reconstructed overall output voltage signal to obtain a waveform quality evaluation result.

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