Impulse voltage peak full-range tracing method based on multi-frequency component weighting iteration

Abstract

The application discloses a kind of based on the peak value tracing and verification method of impulse voltage of multi-frequency component weighting superposition, comprising: impulse voltage calibration factor evaluation model is established: Fourier decomposition is carried out to lightning impulse voltage waveform of specific time parameter, and single impulse voltage waveform is converted into the superposition of countless not stop frequency alternating voltage;Select appropriate frequency segmentation method;The reciprocal of actual measuring device calibration factor can be obtained by calculating the accumulation of weight and ratio product, and then the impulse calibration factor is calculated;Impulse voltage measuring device impulse calibration factor evaluation implementation method: logarithmic form is used for frequency segmentation, and weight is calculated, and for the impulse voltage of different time parameters, the output voltage / input voltage ratio is calculated using convolution method.According to the impulse calibration factor calculation model, the impulse calibration factor is calculated;1kV broadband capacitor voltage dividing device is used to verify the accuracy of the calculation model.

Description

Technical Field

[0001] This invention relates to the field of high voltage measurement technology, and more specifically, to a method for tracing and verifying peak impulse voltage based on the weighted superposition of multiple frequency components. Background Technology

[0002] Lightning and switching impulse voltages can be represented using a double exponential waveform function:

[0003]

[0004] Where f(t) is the impulse voltage signal, A is the coefficient related to the voltage peak value, and τ1 and τ2 are time constants, such as... Figure 6 As shown, τ1 affects the falling portion of the waveform, and τ2 affects the rising portion of the waveform, thus determining the peak time T of the impulse voltage waveform. p Wavefront time T1 and half-peak time T2. Figure 6 This represents the time constant of a typical lightning impulse voltage.

[0005] The physical meaning of the inverse Fourier transform is that any function can be expressed as the sum of many sine and cosine functions of different frequencies, and the amplitude and phase of these frequencies can be obtained through the Fourier transform.

[0006]

[0007] Where F(ω) is the frequency domain representation of a function, f(t) is the time domain representation of the function, and e(jωt) is a complex exponential function. Due to the energy conservation property of the Fourier transform, the energy of the time-domain function f(t) is equal to the square integral of the modulus of its frequency-domain representation F(ω), i.e.:

[0008]

[0009] Therefore, impulse voltage can also be decomposed into a series of sinusoidal AC waveforms of different frequencies, such as... Figure 7 As shown, the voltage amplitude problem in the time domain is transformed into a weighted superposition of the AC components in the frequency domain to evaluate the voltage peak value. Summary of the Invention

[0010] This invention proposes a method for tracing and verifying the peak value of impulse voltage based on the weighted superposition of multiple frequency components, in order to solve the problem of how to trace the peak voltage and scale factor values ​​under impulse voltage.

[0011] According to an invention of the present invention, a method for tracing and verifying the peak impulse voltage based on the weighted superposition of multiple frequency components is provided, the method comprising:

[0012] (1) Establish a calculation model for peak impulse voltage:

[0013] Fourier decomposition of the full-wave impulse voltage of lightning with specific time parameters is performed to extract its spectral information;

[0014] Divide the spectrum information into several frequency bands and select an appropriate segmentation method;

[0015] The energy of each frequency band is calculated according to Parseval's theorem, and the amplitude weight of each frequency band is determined based on the total energy.

[0016] The ratio of the peak values ​​of the output and input signals of the measuring device in different frequency bands is obtained through experimental or computational methods; and

[0017] The first impact scale factor of the measuring device is determined based on the ratio of the amplitude weight to the peak values ​​of the output and input signals.

[0018] (2) Calculate the second impact scale factor of the impact voltage divider based on the aforementioned peak impact voltage calculation model:

[0019] The standard lightning impulse full wave was decomposed using Fourier decomposition and segmented using a logarithmic method.

[0020] The output voltage to input voltage ratio of the measuring device is calibrated using a standard AC / DC current source of 10Hz to 1MHz.

[0021] The step wave response g(t) of the impulse voltage divider was measured. An analytical method was used to fit the standard digital waveform of the AC voltage. The output voltage waveform for AC voltages above 1MHz was calculated using a convolution method, thus obtaining the output voltage / input voltage ratio.

[0022] Calculate the second impact scale factor based on the aforementioned peak voltage calculation model for impact voltage.

[0023] (3) The accuracy of the peak voltage calculation model of the impulse voltage was verified using a 1kV wideband capacitor voltage divider device;

[0024] The impact scale factor and linearity of a 1kV wideband capacitive voltage divider at different frequency AC voltages were measured using a 1kV AC / DC voltage standard source.

[0025] The third impulse scale factor of a 1kV broadband capacitive voltage divider was measured using a 1kV standard impulse voltage source.

[0026] The accuracy of the peak voltage calculation model for the impulse voltage is determined based on the consistency of the first impulse scale factor, the second impulse scale factor, multiple impulse scale factors for AC voltages of different frequencies, and the third impulse scale factor. Preferably, the full wave of the impulse voltage is a standard lightning full wave with time parameters of 0.84 / 60, 1.2 / 60, and 1.56 / 60.

[0027] Preferably, the segmentation using a logarithmic method includes:

[0028] For frequencies ranging from 10Hz to 100MHz or within 100Hz, set the frequency band interval to 10Hz.

[0029] The frequency range is 100Hz to 1kHz, and the frequency interval is set to 100Hz.

[0030] The frequency range is 1kHz to 10kHz, and the frequency band interval is set to 1kHz.

[0031] The frequency range is 10kHz to 100kHz, and the frequency interval is set to 10kHz.

[0032] The frequency range is within 100kHz to 1MHz, and the frequency band interval is set to 100kHz.

[0033] The frequency range is 1MHz to 10MHz, and the frequency band interval is set to 1MHz.

[0034] The frequency range is 10MHz to 100MHz, and the frequency band interval is set to 10MHz.

[0035] Preferably, for impulse voltages with different time parameters, different weights are assigned to the amplitude of each frequency band.

[0036] Preferably, the high-voltage capacitor of the 1kV wideband capacitive voltage divider is a uniform, upright, fully shielded, gas-insulated standard capacitor, including an upper flange, a high-voltage bushing, a metal shielding cylinder, a high-voltage guide rod, and an electrode system. The electrode system includes a high-voltage electrode, a low-voltage electrode, and a shielding electrode. The electrode material is stainless steel or aluminum with a surface roughness of less than 2. One end of the high-voltage guide rod is connected to the upper flange, and the other end is connected to the high-voltage electrode. The electrode system is coaxially arranged, with the high-voltage electrode, low-voltage electrode, and shielding electrode arranged sequentially from the center outwards. The high-voltage electrode is fixed to the bottom surface of the shielding cylinder by an insulating rod, and the high-voltage electrode has a structure that is longer at the top and shorter at the bottom. The low-voltage electrode and the shielding electrode are fixed on an epoxy cylinder, and the epoxy cylinder is fixed to the bottom surface of the shielding cylinder. The distance between the low-voltage electrode and the shielding electrode is 3mm, and the lead wire of the low-voltage electrode is a 50-ohm wave impedance metal part. The low-voltage capacitor uses multiple non-inductive multilayer ceramic capacitors. The 1kV voltage divider is designed with a rated output voltage of 1V and a scale factor of 1000. To eliminate the influence of the load on the scale factor, an impedance transformer is added between the measuring cable and the digital sensor.

[0037] Preferably, this tracing method can be used not only for tracing the impulse voltage measuring device, but also for tracing the peak measurement error of the digital recorder.

[0038] According to another aspect of the present invention, a system for tracing and verifying peak impulse voltage based on weighted superposition of multiple frequency components is provided, characterized in that the system comprises:

[0039] A device is established to create a calculation model for the peak impulse voltage.

[0040] Fourier decomposition of the full-wave impulse voltage of lightning with specific time parameters is performed to extract its spectral information;

[0041] Divide the spectrum information into several frequency bands and select an appropriate segmentation method;

[0042] The energy of each frequency band is calculated according to Parseval's theorem, and the amplitude weight of each frequency band is determined based on the total energy.

[0043] The ratio of the peak values ​​of the output and input signals of the measuring device in different frequency bands is obtained through experimental or computational methods; and

[0044] The first impact scale factor of the measuring device is determined based on the ratio of the amplitude weight to the peak values ​​of the output and input signals.

[0045] The computing device is used to calculate the second impulse scale factor of the impulse voltage divider based on the impulse voltage peak voltage calculation model.

[0046] The standard lightning impulse full wave was decomposed using Fourier decomposition and segmented using a logarithmic method.

[0047] The output voltage to input voltage ratio of the measuring device is calibrated using a standard AC / DC current source of 10Hz to 1MHz.

[0048] The step wave response g(t) of the impulse voltage divider was measured. An analytical method was used to fit the standard digital waveform of the AC voltage. The output voltage waveform for AC voltages above 1MHz was calculated using a convolution method, thus obtaining the output voltage / input voltage ratio.

[0049] Calculate the second impact scale factor based on the aforementioned peak voltage calculation model for impact voltage.

[0050] A verification device is used to verify the accuracy of the peak voltage calculation model of the impulse voltage using a 1kV wideband capacitor voltage divider.

[0051] The impact scale factor and linearity of a 1kV wideband capacitive voltage divider at different frequency AC voltages were measured using a 1kV AC / DC voltage standard source.

[0052] The third impulse scale factor of a 1kV broadband capacitive voltage divider was measured using a 1kV standard impulse voltage source.

[0053] The accuracy of the peak voltage calculation model for the impulse voltage is determined based on the consistency of the first impulse scale factor, the second impulse scale factor, multiple impulse scale factors for AC voltages of different frequencies, and the third impulse scale factor.

[0054] Preferably, the full wave of the impulse voltage is a standard lightning full wave with time parameters of 0.84 / 60, 1.2 / 60, and 1.56 / 60.

[0055] Preferably, the segmentation using a logarithmic method includes:

[0056] For frequencies ranging from 10Hz to 100MHz or within 100Hz, set the frequency band interval to 10Hz.

[0057] The frequency range is 100Hz to 1kHz, and the frequency interval is set to 100Hz.

[0058] The frequency range is 1kHz to 10kHz, and the frequency band interval is set to 1kHz.

[0059] The frequency range is 10kHz to 100kHz, and the frequency interval is set to 10kHz.

[0060] The frequency range is within 100kHz to 1MHz, and the frequency band interval is set to 100kHz.

[0061] The frequency range is 1MHz to 10MHz, and the frequency band interval is set to 1MHz.

[0062] The frequency range is 10MHz to 100MHz, and the frequency band interval is set to 10MHz.

[0063] Preferably, it further includes setting different weights for the amplitude of each frequency band for impulse voltages with different time parameters.

[0064] This invention provides a method and system for tracing the full range of peak impulse voltage based on multi-frequency component weighted iteration, comprising: performing a Fourier transform on the full-wave lightning surge to obtain the amplitude proportions of AC voltage in different frequency bands; obtaining the response characteristics of a 1kV, 10kV, and 200kV capacitive voltage divider based on step wave response tests; acquiring standard wave data of AC voltage at different frequencies, and calculating the output voltage error of the capacitive voltage divider when inputting standard wave data of AC voltage at different frequencies using a convolution method based on the response characteristics; determining a calculation model for the peak impulse voltage measurement error based on the amplitude proportions and the output voltage error; and using a 1kV AC current... The frequency characteristics of a 10kV capacitive voltage divider are measured using a standard source. The power frequency calibration factor and linearity of the 10kV capacitive voltage divider are obtained using a 10kV power frequency voltage standard source, a 10kV harmonic voltage standard source, and a 10kV impulse voltage standard generator. The impulse calibration factor and linearity of the 1kV capacitive voltage divider under different frequency AC voltages and impulse voltages are measured using a 1kV AC voltage standard source and a 1kV impulse voltage standard generator. Based on the boundary conditions and the measurement results of the power frequency calibration factor and impulse calibration factor at 10kV, the equivalence of the power frequency voltage coefficient and impulse voltage coefficient of a 200kV capacitive voltage divider is determined. This invention utilizes a voltage divider based on a vertically shielded gas standard capacitor as a transfer standard to trace the source of voltage peak error under high impulse voltages. Attached Figure Description

[0065] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures:

[0066] Figure 1 This is a flowchart of a method for tracing and verifying peak impulse voltage based on weighted superposition of multiple frequency components according to an embodiment of the present invention.

[0067] Figure 2 This is a flowchart of the impulse voltage peak tracing and verification method according to an embodiment of the present invention;

[0068] Figure 3 This is a schematic diagram of the structure of a 1kV wideband capacitor voltage divider according to an embodiment of the present invention; 1—upper flange, 2—high voltage bushing, 3—high voltage guide rod, 4—aluminum can, 5—shielding electrode, 6—epoxy cylinder, 7—low voltage electrode, 8—high voltage electrode, 9—output terminal, 10—spring contact finger, 11—high voltage damping resistor, 12—low voltage damping resistor, 13—low voltage capacitor, 14—coaxial cable, 15—impedance transformation unit, 16—digital recorder.

[0069] Figure 4 This is a circuit diagram of a 1kV wideband capacitor voltage divider according to an embodiment of the present invention;

[0070] Figure 5This is a schematic diagram of the impulse voltage peak source tracing and verification method 500 based on multi-frequency component weighted superposition according to an embodiment of the present invention.

[0071] Figure 6 A schematic diagram of a full-wave double-exponential impulse voltage; and

[0072] Figure 7 This is a schematic diagram of the full-wave frequency response characteristics of lightning. Detailed Implementation

[0073] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0074] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0075] Figure 1 This is a flowchart of a full-range source tracing method for peak impulse voltage based on multi-frequency component weighted iteration according to an embodiment of the present invention. Figure 1 As shown, the impulse voltage peak tracing and verification method based on multi-frequency component weighted superposition provided by the embodiments of the present invention transforms the time-domain impulse voltage peak assessment into a frequency-domain component superposition problem, bridging the impulse voltage scale factor tracing to the national standard value of power frequency voltage. The impulse voltage peak tracing and verification method 100 based on multi-frequency component weighted superposition provided by the embodiments of the present invention includes: 101-104 representing the impulse scale factor assessment model; 105-108 representing the impulse voltage scale factor assessment implementation method; and 109-111 representing the method verification.

[0076] Starting from step 101, in step 101, Fourier decomposition is performed on the full lightning wave, and an appropriate frequency segmentation method is selected.

[0077] In step 102, the energy of each frequency band is calculated according to the Parseval theorem, and the amplitude weight of each frequency band is determined based on the total energy.

[0078] In step 103, the ratio of the peak values ​​of the output and input signals of the measuring device in different frequency bands is obtained through experimental or calculation methods.

[0079] In step 104, the impact scale factor of the measuring device is determined based on the amplitude weight and the ratio of the peak values ​​of the output and input signals.

[0080] In step 105, the standard lightning full-wave multi-frequency decomposition is performed by segmentation using a logarithmic method.

[0081] In step 106, the output voltage / input voltage ratio of the measuring device within 1MHz is calibrated using a standard AC / DC current source; the step wave response of the impulse voltage measuring device is measured, and the output voltage / input voltage ratio above 1MHz is calculated using the convolution method.

[0082] Specifically, the present invention provides a method for tracing and verifying the peak impulse voltage based on the weighted superposition of multiple frequency components, the method comprising:

[0083] (1) Establish a calculation model for peak impulse voltage:

[0084] Fourier decomposition of the full-wave impulse voltage of lightning with specific time parameters is performed to extract its spectral information;

[0085] Divide the spectrum information into several frequency bands and select an appropriate segmentation method;

[0086] The energy of each frequency band is calculated according to Parseval's theorem, and the amplitude weight of each frequency band is determined based on the total energy.

[0087] The ratio of the peak values ​​of the output and input signals of the measuring device in different frequency bands is obtained through experimental or computational methods; and

[0088] The first impact scale factor of the measuring device is determined based on the ratio of the amplitude weight to the peak values ​​of the output and input signals.

[0089] (2) Calculate the second impact scale factor of the impact voltage divider based on the aforementioned peak impact voltage calculation model:

[0090] The standard lightning impulse full wave was decomposed using Fourier decomposition and segmented using a logarithmic method.

[0091] The output voltage to input voltage ratio of the measuring device is calibrated using a standard AC / DC current source of 10Hz to 1MHz.

[0092] The step wave response g(t) of the impulse voltage divider was measured. An analytical method was used to fit the standard digital waveform of the AC voltage. The output voltage waveform for AC voltages above 1MHz was calculated using a convolution method, thus obtaining the output voltage / input voltage ratio.

[0093] Calculate the second impact scale factor based on the aforementioned peak voltage calculation model for impact voltage.

[0094] (3) The accuracy of the peak voltage calculation model of the impulse voltage was verified using a 1kV wideband capacitor voltage divider device;

[0095] The impact scale factor and linearity of a 1kV wideband capacitive voltage divider at different frequency AC voltages were measured using a 1kV AC / DC voltage standard source.

[0096] The third impulse scale factor of a 1kV broadband capacitive voltage divider was measured using a 1kV standard impulse voltage source.

[0097] The accuracy of the peak voltage calculation model is determined based on the consistency of the first impact scale factor, the second impact scale factor, multiple impact scale factors for AC voltages of different frequencies, and the third impact scale factor. For example, if the values ​​of the first impact scale factor, the second impact scale factor, multiple impact scale factors for AC voltages of different frequencies, and the third impact scale factor are all the same (consistent), then the accuracy of the peak voltage calculation model is determined to be high. For example, if the values ​​of the first impact scale factor, the second impact scale factor, multiple impact scale factors for AC voltages of different frequencies, and the third impact scale factor are all within a preset value range, then the accuracy of the peak voltage calculation model is determined to be high. For example, if the variance of the values ​​of the first impact scale factor, the second impact scale factor, multiple impact scale factors for AC voltages of different frequencies, and the third impact scale factor is less than a variance threshold, then the accuracy of the peak voltage calculation model is determined to be high.

[0098] According to one embodiment, the full wave of the impulse voltage is a standard lightning full wave with time parameters of 0.84 / 60, 1.2 / 60, and 1.56 / 60.

[0099] According to one embodiment, the segmentation using a logarithmic method includes:

[0100] For frequencies ranging from 10Hz to 100MHz or within 100Hz, set the frequency band interval to 10Hz.

[0101] The frequency range is 100Hz to 1kHz, and the frequency interval is set to 100Hz.

[0102] The frequency range is 1kHz to 10kHz, and the frequency band interval is set to 1kHz.

[0103] The frequency range is 10kHz to 100kHz, and the frequency interval is set to 10kHz.

[0104] The frequency range is within 100kHz to 1MHz, and the frequency band interval is set to 100kHz.

[0105] The frequency range is 1MHz to 10MHz, and the frequency band interval is set to 1MHz.

[0106] The frequency range is 10MHz to 100MHz, and the frequency band interval is set to 10MHz.

[0107] Preferably, the specific segmentation method is as follows: the frequency range is 10Hz to 100MHz, the frequency segments within 100Hz are spaced 10Hz apart, the frequency segments above 100kHz are spaced 100Hz apart, the frequency segments within 1kHz to 10kHz are spaced 1kHz apart, the frequency segments within 10kHz to 100kHz are spaced 10kHz apart, the frequency segments within 100kHz to 1MHz are spaced 100kHz apart, the frequency segments within 1MHz to 10MHz are spaced 1MHz apart, and the frequency segments within 10MHz to 100MHz are spaced 10MHz apart. The weights are calculated through specific segmentation.

[0108] Preferably, the convolution calculation method requires the measured voltage waveform and the step wave response waveform, and the convolution calculation outputs the voltage waveform.

[0109] In step 107, the impact scale factor is calculated based on the evaluation model 104.

[0110] In step 108, a 1kV wideband capacitor divider is used to verify the accuracy of the model and method.

[0111] Preferably, the high-voltage capacitor of the 1kV broadband capacitive voltage divider is a uniform, upright, fully shielded, gas-insulated standard capacitor, comprising an upper flange, a high-voltage bushing, a metal shielding cylinder, a high-voltage guide rod, and an electrode system; the electrode system includes a high-voltage electrode, a low-voltage electrode, and a shielding electrode; the electrode material is stainless steel or aluminum, with a surface roughness of less than 2; one end of the high-voltage guide rod is connected to the upper flange, and the other end is connected to the high-voltage electrode; the electrode system is coaxially arranged, with the high-voltage electrode, low-voltage electrode, and shielding electrode arranged sequentially from the center outwards; the high-voltage electrode is fixed to the bottom surface of the shielding cylinder by an insulating rod. The high-voltage electrode has a longer top and shorter bottom structure; the low-voltage electrode and shielding electrode are fixed to the epoxy cylinder, which is in turn fixed to the bottom of the shielding cylinder; the distance between the low-voltage electrode and the shielding electrode is 3mm; the low-voltage electrode lead is a 50-ohm impedance metal component; the capacitance of the high-voltage standard capacitors is 10pF; the low-voltage capacitors are fixed to the lead metal components by screws, and multiple non-inductive multilayer ceramic capacitors are used. The 1kV voltage divider is designed with a rated output voltage of 1V and a scale factor of 1000. To eliminate the influence of the load on the scale factor, an impedance transformer is added between the measuring cable and the digital unit.

[0112] In one embodiment, for impulse voltages with different time parameters, different weights are assigned to the amplitude of each frequency band.

[0113] In one embodiment, the high-voltage capacitor of the 1kV wideband capacitive voltage divider is a uniform, upright, fully shielded, gas-insulated standard capacitor, comprising an upper flange, a high-voltage bushing, a metal shielding cylinder, a high-voltage guide rod, and an electrode system. The electrode system includes a high-voltage electrode, a low-voltage electrode, and a shielding electrode. The electrode material is stainless steel or aluminum with a surface roughness of less than 2. One end of the high-voltage guide rod is connected to the upper flange, and the other end is connected to the high-voltage electrode. The electrode system is coaxially arranged, with the high-voltage electrode, low-voltage electrode, and shielding electrode arranged sequentially from the center outwards. The high-voltage electrode is fixed to the bottom surface of the shielding cylinder by an insulating rod, and the high-voltage electrode has a structure that is longer at the top and shorter at the bottom. The low-voltage electrode and the shielding electrode are fixed on an epoxy cylinder, and the epoxy cylinder is fixed to the bottom surface of the shielding cylinder. The distance between the low-voltage electrode and the shielding electrode is 3mm, and the lead wire of the low-voltage electrode is a 50-ohm wave impedance metal part. The low-voltage capacitor uses multiple non-inductive multilayer ceramic capacitors. The 1kV voltage divider is designed with a rated output voltage of 1V and a scale factor of 1000. To eliminate the influence of the load on the scale factor, an impedance transformer is added between the measuring cable and the digital sensor.

[0114] In one embodiment, the tracing method can be used not only for tracing impulse voltage measuring devices, but also for tracing peak measurement errors of digital recorders.

[0115] Combination Figure 3 and Figure 4 As shown, in this invention, the high-voltage capacitor of the 1kV broadband capacitive voltage divider is a vertically mounted, fully shielded, gas-insulated standard capacitor, comprising an upper flange, a high-voltage bushing, a metal shielding cylinder, a high-voltage guide rod, and an electrode system. The electrode system includes a high-voltage electrode, a low-voltage electrode, and a shielding electrode. The electrodes are made of stainless steel or aluminum with a surface roughness of less than 2. One end of the high-voltage guide rod is connected to the upper flange, and the other end is connected to the high-voltage electrode. The electrode system is coaxially arranged, with the high-voltage electrode, low-voltage electrode, and shielding electrode arranged sequentially from the center outwards. The high-voltage electrode is fixed to the bottom surface of the shielding cylinder by an insulating rod; for ease of installation and optimized electric field distribution, the high-voltage electrode has a structure that is longer at the top and shorter at the bottom. The low-voltage electrode and the shielding electrode are fixed to the epoxy cylinder, which is fixed to the bottom surface of the shielding cylinder. The distance between the low-voltage electrode and the shielding electrode is 3mm, and the low-voltage electrode lead is designed as a 50-ohm impedance metal component. The capacitance of each of the three high-voltage standard capacitors is 10pF.

[0116] The low-voltage capacitor is fixed to the lead metal part by screws. The low-voltage capacitor uses multiple non-inductive multilayer ceramic capacitors. The 1kV voltage divider is designed with a rated output voltage of 1V and a scale factor of 1000.

[0117] The damping resistor consists of two parts: an external damping resistor and an internal damping resistor. The external damping resistor is connected to the beginning of the high-voltage lead and is used to dampen the high-frequency oscillations in the rising section. The resistor is a high-voltage resistor wound with two wires in parallel. During design, the length of the resistor is determined by the outer insulation, and the diameter of the resistance wire is determined by calculating the temperature rise of the resistance wire and the withstand voltage of the insulation varnish. Generally, the temperature rise is less than 100℃. The internal damping resistor is used to dampen the oscillations of the inductance and capacitance on the high-voltage conductor. The sum of the external and internal damping resistors is approximately 300 ohms.

[0118] In step 109, a 1kV AC / DC voltage standard source is used to measure the scale factor and linearity of the 1kV wideband capacitive voltage divider at different frequency AC voltages.

[0119] In step 110, the impulse scale factor of the 1kV broadband capacitor voltage divider is measured using a 1kV standard impulse voltage source.

[0120] In step 111, the consistency of the impact scale factors obtained by the different methods described above is compared.

[0121] The tracing method of this invention can solve the problem of voltage peak tracing in 100kV impulse voltage dividers. The specific process includes:

[0122] (1) Establishment of an evaluation model for measurement error

[0123] The 1.2 / 50μs lightning full wave was Fourier decomposed using FFT, and the amplitude content at different frequencies was integrated and calculated. Examples are shown in Table 1. The frequency range is 10Hz to 100MHz, with frequency intervals of 10Hz below 100Hz, 100Hz above 1kHz, 1kHz between 1kHz and 10kHz, 10kHz between 10kHz and 100kHz, 100kHz between 100kHz and 1MHz, 1MHz between 1MHz and 10MHz, and 10MHz between 10MHz and 100MHz. Furthermore, weights were calculated based on the amplitude at different frequencies. The step wave response waveform of a 100kV impulse voltage measuring device was measured.

[0124] Below 1MHz, the amplitude-frequency characteristics of the capacitor voltage divider were measured using a standard AC voltage source Fluke5730 and an AC voltmeter Fluke5790, thereby calculating the ratio of output voltage to input voltage in different frequency ranges, as shown in Table 1.

[0125] Alternatively, waveform fitting methods can be used to obtain standard waveform databases for different frequency bands, especially for amplitude-frequency characteristics of devices that cannot be directly measured above 1MHz. Given the response waveform and the measured AC voltage waveform, the output / input voltage ratio of the voltage divider can be calculated using the convolution method. Furthermore, the impulse calibration factor is calculated to be 1476.696, with a deviation of 0.06% from the power frequency voltage.

[0126] Table 2 Calculation weights for different lightning impulse voltages

[0127]

[0128]

[0129] (2) Method Validation

[0130] The calibration factor and linearity of the 1kV capacitive voltage divider were measured using a 1kV AC voltage standard source and a 1kV impulse voltage standard generator under AC voltage and impulse voltage at different frequencies. Table 3 shows that the impulse calibration factor obtained through multi-frequency decomposition and weighted superposition is 100.16, and the impulse calibration factor obtained using the standard impulse voltage generator is 100.21. This verifies the correctness and feasibility of the method of this invention.

[0131] Table 31: Scale factors of the 1kV capacitor voltage divider at different frequencies

[0132]

[0133] Figure 5 This is a schematic diagram of the structure of the impulse voltage peak tracing and development method 500 based on multi-frequency component weighted superposition according to an embodiment of the present invention. Figure 5 As shown, the impulse voltage peak tracing and verification method 500 based on multi-frequency component weighted superposition provided by the embodiments of the present invention includes: a voltage peak and impulse scale factor evaluation model, an impulse scale factor evaluation implementation method 502, and a method verification unit 503.

[0134] The impulse voltage peak value and impulse scale factor tracing and verification method 500 based on multi-frequency component weighted superposition in an embodiment of the present invention corresponds to the impulse voltage peak value full-range tracing method 100 based on multi-frequency component weighted iteration in another embodiment of the present invention.

[0135] For example, in one embodiment, a system for tracing and verifying peak impulse voltage based on weighted superposition of multiple frequency components is provided, characterized in that the system includes:

[0136] A device is established to create a calculation model for the peak impulse voltage.

[0137] Fourier decomposition of the full-wave impulse voltage of lightning with specific time parameters is performed to extract its spectral information;

[0138] Divide the spectrum information into several frequency bands and select an appropriate segmentation method;

[0139] The energy of each frequency band is calculated according to Parseval's theorem, and the amplitude weight of each frequency band is determined based on the total energy.

[0140] The ratio of the peak values ​​of the output and input signals of the measuring device in different frequency bands is obtained through experimental or computational methods; and

[0141] The first impact scale factor of the measuring device is determined based on the ratio of the amplitude weight to the peak values ​​of the output and input signals.

[0142] The computing device is used to calculate the second impulse scale factor of the impulse voltage divider based on the impulse voltage peak voltage calculation model.

[0143] The standard lightning impulse full wave was decomposed using Fourier decomposition and segmented using a logarithmic method.

[0144] The output voltage to input voltage ratio of the measuring device is calibrated using a standard AC / DC current source of 10Hz to 1MHz.

[0145] The step wave response g(t) of the impulse voltage divider was measured. An analytical method was used to fit the standard digital waveform of the AC voltage. The output voltage waveform for AC voltages above 1MHz was calculated using a convolution method, thus obtaining the output voltage / input voltage ratio.

[0146] Calculate the second impact scale factor based on the aforementioned peak voltage calculation model for impact voltage.

[0147] A verification device is used to verify the accuracy of the peak voltage calculation model of the impulse voltage using a 1kV wideband capacitor voltage divider.

[0148] The impact scale factor and linearity of a 1kV wideband capacitive voltage divider at different frequency AC voltages were measured using a 1kV AC / DC voltage standard source.

[0149] The third impulse scale factor of a 1kV broadband capacitive voltage divider was measured using a 1kV standard impulse voltage source.

[0150] The accuracy of the peak voltage calculation model for the impulse voltage is determined based on the consistency of the first impulse scale factor, the second impulse scale factor, multiple impulse scale factors for AC voltages of different frequencies, and the third impulse scale factor.

[0151] In one embodiment, the full wave of the impulse voltage is a standard lightning full wave with time parameters of 0.84 / 60, 1.2 / 60, and 1.56 / 60.

[0152] In one embodiment, the segmentation using a logarithmic method includes:

[0153] For frequencies ranging from 10Hz to 100MHz or within 100Hz, set the frequency band interval to 10Hz.

[0154] The frequency range is 100Hz to 1kHz, and the frequency interval is set to 100Hz.

[0155] The frequency range is 1kHz to 10kHz, and the frequency band interval is set to 1kHz.

[0156] The frequency range is 10kHz to 100kHz, and the frequency interval is set to 10kHz.

[0157] The frequency range is within 100kHz to 1MHz, and the frequency band interval is set to 100kHz.

[0158] The frequency range is 1MHz to 10MHz, and the frequency band interval is set to 1MHz.

[0159] The frequency range is 10MHz to 100MHz, and the frequency band interval is set to 10MHz.

[0160] In one embodiment, the method further includes setting different weights for the amplitude of each frequency band for impulse voltages with different time parameters.

[0161] The invention has been described with reference to a few embodiments. However, as will be known to those skilled in the art, and as defined in the appended claims, other embodiments besides those disclosed above fall equivalently within the scope of the invention.

[0162] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the art, unless otherwise expressly defined herein. All references to “a / the / the [device, component, etc.]” ​​are openly interpreted as at least one instance of said device, component, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed unless explicitly stated otherwise.

[0163] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application 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.

[0164] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. 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... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0165] 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.

[0166] 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.

[0167] 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 method for tracing and verifying peak impulse voltage based on weighted superposition of multiple frequency components, characterized in that, The method includes: (1) Establish a calculation model for peak impulse voltage: Fourier decomposition of the full-wave impulse voltage of lightning with specific time parameters is performed to extract its spectral information; Divide the spectrum information into several frequency bands and select an appropriate segmentation method; The energy of each frequency band is calculated according to Parseval's theorem, and the amplitude weight of each frequency band is determined based on the total energy. The ratio of the peak values ​​of the output and input signals of the measuring device in different frequency bands is obtained through experimental or computational methods; and The first impact scale factor of the measuring device is determined based on the ratio of the amplitude weight to the peak values ​​of the output and input signals. (2) Calculate the second impact scale factor of the impact voltage divider based on the aforementioned peak impact voltage calculation model: The standard lightning impulse full wave was decomposed using Fourier decomposition and segmented using a logarithmic method. The output voltage to input voltage ratio of the measuring device is calibrated using a standard AC / DC current source of 10Hz to 1MHz. The step wave response g(t) of the impulse voltage divider was measured. An analytical method was used to fit the standard digital waveform of the AC voltage. The output voltage waveform for AC voltages above 1MHz was calculated using a convolution method, thus obtaining the output voltage / input voltage ratio. Calculate the second impact scale factor based on the aforementioned peak voltage calculation model for impact voltage. (3) The accuracy of the peak voltage calculation model of the impulse voltage was verified using a 1kV wideband capacitor voltage divider device; The impact scale factor and linearity of a 1kV wideband capacitive voltage divider at different frequency AC voltages were measured using a 1kV AC / DC voltage standard source. The third impulse scale factor of a 1kV broadband capacitive voltage divider was measured using a 1kV standard impulse voltage source. The accuracy of the peak voltage calculation model for the impulse voltage is determined based on the consistency of the first impulse scale factor, the second impulse scale factor, multiple impulse scale factors for AC voltages of different frequencies, and the third impulse scale factor.

2. The method according to claim 1, characterized in that, The full wave of the impulse voltage is a standard lightning full wave with time parameters of 0.84 / 60, 1.2 / 60, and 1.56 / 60.

3. The method according to claim 1, characterized in that, The segmentation using a logarithmic method includes: For frequencies ranging from 10Hz to 100MHz or within 100Hz, set the frequency band interval to 10Hz. The frequency range is 100Hz to 1kHz, and the frequency interval is set to 100Hz. The frequency range is 1kHz to 10kHz, and the frequency interval is set to 1kHz. The frequency range is 10kHz to 100kHz, and the frequency interval is set to 10kHz. The frequency range is 100kHz to 1MHz, and the frequency band interval is set to 100kHz. The frequency range is 1MHz to 10MHz, and the frequency band interval is set to 1MHz. The frequency range is 10MHz to 100MHz, and the frequency band interval is set to 10MHz.

4. The method according to claim 1, characterized in that, For impulse voltages with different time parameters, different weights are assigned to the amplitude of each frequency band.

5. The method according to claim 1, characterized in that, The high-voltage capacitor of the 1kV wideband capacitive voltage divider is a uniform, upright, fully shielded, gas-insulated standard capacitor, including an upper flange, a high-voltage bushing, a metal shielding cylinder, a high-voltage guide rod, and an electrode system. The electrode system includes a high-voltage electrode, a low-voltage electrode, and a shielding electrode. The electrode material is stainless steel or aluminum with a surface roughness of less than 2. One end of the high-voltage guide rod is connected to the upper flange, and the other end is connected to the high-voltage electrode. The electrode system is coaxially arranged, with the high-voltage electrode, low-voltage electrode, and shielding electrode arranged sequentially from the center outwards. The high-voltage electrode is fixed to the bottom surface of the shielding cylinder by an insulating rod, and the high-voltage electrode has a structure that is longer at the top and shorter at the bottom. The low-voltage electrode and the shielding electrode are fixed on an epoxy cylinder, and the epoxy cylinder is fixed to the bottom surface of the shielding cylinder. The distance between the low-voltage electrode and the shielding electrode is 3mm, and the lead wire of the low-voltage electrode is a 50-ohm wave impedance metal part. The low-voltage capacitor uses multiple non-inductive multilayer ceramic capacitors. The 1kV voltage divider is designed with a rated output voltage of 1V and a scale factor of 1000. To eliminate the influence of the load on the scale factor, an impedance transformer is added between the measuring cable and the digital sensor.

6. The method according to claim 1, characterized in that, This tracing method can be used not only for tracing impulse voltage measuring devices, but also for tracing peak measurement errors in digital recorders.

7. A system for tracing and verifying peak impulse voltage based on weighted superposition of multiple frequency components, characterized in that, The system includes: A device is established to create a calculation model for the peak impulse voltage. Fourier decomposition of the full-wave impulse voltage of lightning with specific time parameters is performed to extract its spectral information; Divide the spectrum information into several frequency bands and select an appropriate segmentation method; The energy of each frequency band is calculated according to Parseval's theorem, and the amplitude weight of each frequency band is determined based on the total energy. The ratio of the peak values ​​of the output and input signals of the measuring device in different frequency bands is obtained through experimental or computational methods; and The first impact scale factor of the measuring device is determined based on the ratio of the amplitude weight to the peak values ​​of the output and input signals. The computing device is used to calculate the second impulse scale factor of the impulse voltage divider based on the impulse voltage peak voltage calculation model. The standard lightning impulse full wave was decomposed using Fourier decomposition and segmented using a logarithmic method. The output voltage to input voltage ratio of the measuring device is calibrated using a standard AC / DC current source of 10Hz to 1MHz. The step wave response g(t) of the impulse voltage divider was measured. An analytical method was used to fit the standard digital waveform of the AC voltage. The output voltage waveform for AC voltages above 1MHz was calculated using a convolution method, thus obtaining the output voltage / input voltage ratio. Calculate the second impact scale factor based on the aforementioned peak voltage calculation model for impact voltage. A verification device is used to verify the accuracy of the peak voltage calculation model of the impulse voltage using a 1kV wideband capacitor voltage divider. The impact scale factor and linearity of a 1kV wideband capacitive voltage divider at different frequency AC voltages were measured using a 1kV AC / DC voltage standard source. The third impulse scale factor of a 1kV broadband capacitive voltage divider was measured using a 1kV standard impulse voltage source. The accuracy of the peak voltage calculation model for the impulse voltage is determined based on the consistency of the first impulse scale factor, the second impulse scale factor, multiple impulse scale factors for AC voltages of different frequencies, and the third impulse scale factor.

8. The system according to claim 7, characterized in that, The full wave of the impulse voltage is a standard lightning full wave with time parameters of 0.84 / 60, 1.2 / 60, and 1.56 / 60.

9. The system according to claim 7, characterized in that, The segmentation using a logarithmic method includes: For frequencies ranging from 10Hz to 100MHz or within 100Hz, set the frequency band interval to 10Hz. The frequency range is 100Hz to 1kHz, and the frequency interval is set to 100Hz. The frequency range is 1kHz to 10kHz, and the frequency interval is set to 1kHz. The frequency range is 10kHz to 100kHz, and the frequency interval is set to 10kHz. The frequency range is 100kHz to 1MHz, and the frequency band interval is set to 100kHz. The frequency range is 1MHz to 10MHz, and the frequency band interval is set to 1MHz. The frequency range is 10MHz to 100MHz, and the frequency band interval is set to 10MHz.

10. The system according to claim 7, characterized in that, It also includes setting different weights for the amplitude of each frequency band for impulse voltages with different time parameters.

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