CN116449085A - Voltage flicker acceleration detection method, system and medium - Google Patents
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Abstract
The invention discloses a voltage flicker acceleration detection method, a system and a medium, wherein the voltage flicker acceleration detection method comprises the steps of squaring a voltage signal to be detected to obtain a voltage square signal; obtaining the direct current bias of the voltage square signal; subtracting the direct current bias of the voltage square signal from the voltage square signal to obtain an optimized voltage signal; and performing demodulation filtering, sensitivity weighting filtering, squaring, smoothing weighting filtering and statistical processing on the optimized voltage signal to obtain a voltage flicker detection result. The invention aims to solve the problems that the demodulation filtering convergence speed is low and the flicker detection precision is influenced in the conventional IEC flicker detection method, and improve the detection precision while ensuring the flicker detection speed.
Description
Technical Field
The invention belongs to the technical field of power systems, and particularly relates to a voltage flicker acceleration detection method, a system and a medium.
Background
With the development of industrial technology, a large amount of high-power variable load, such as a large electric arc furnace, a large rolling mill, an electric locomotive, an electric welding machine and the like, enters a power grid, so that the power load is rapidly changed, voltage fluctuation and flickering are caused, and various electric equipment running in the power grid is seriously affected. In order to solve the problem of grid voltage flicker, the voltage flicker must be detected in time. At present, the widely used flicker detection method is an IEC recommended IEC flicker detection method, which comprises 6 steps, namely square detection, demodulation filtering, sensitivity weighting filtering, square, smooth weighting filtering and statistical processing, wherein the IEC provides analog transfer functions of all links, and a microprocessor can be used for carrying out digital signal processing on acquired sensor signals in practical engineering application to realize the steps. Although the calculation method is simple to realize, the convergence rate of demodulation filtering in the second link is low, and sampling data before convergence can not be used as invalid data, so that the accuracy of flicker detection is affected.
Disclosure of Invention
The invention aims to solve the technical problems: aiming at the problems in the prior art, the invention provides a voltage flicker acceleration detection method, a system and a medium, which aim to solve the problems that the demodulation filtering convergence speed of the conventional IEC flicker detection method is low, influence the accuracy of flicker detection, and improve the accuracy of detection while ensuring the flicker detection speed.
In order to solve the technical problems, the invention adopts the following technical scheme:
a voltage flicker acceleration detection method comprises the following steps:
s101, squaring a voltage signal to be detected to obtain a voltage square signal;
s102, obtaining direct current bias of a voltage square signal;
s103, subtracting the direct current bias of the voltage square signal from the voltage square signal to obtain an optimized voltage signal;
and S104, performing demodulation filtering, sensitivity weighting filtering, squaring, smoothing weighting filtering and statistical processing on the optimized voltage signal to obtain a voltage flicker detection result.
Optionally, the functional expression of the voltage signal to be detected in step S101 is:
u(t)＝(1+m*cos(Ωt))cos(ωt)，
in the above formula, u (t) represents a voltage signal to be detected at a time t, A is the amplitude of the power frequency carrier voltage, m is the amplitude of the amplitude-modulated wave voltage, Ω is the angular frequency of the amplitude-modulated wave voltage, t is the time, ω is the angular frequency of the power frequency carrier voltage; m is cos (Ω t) represents a fluctuating voltage.
Optionally, in step S101, the square of the voltage signal to be detected is performed to obtain a function expression of the voltage square signal, where the function expression is:
in the above, u 2 (t) represents a voltage square signal, A is the amplitude of the power frequency carrier voltage, m is the amplitude of the amplitude-modulated wave voltage, Ω is the angular frequency of the amplitude-modulated wave voltage, t is the time, ω is the angular frequency of the power frequency carrier voltage.
Optionally, the step S102 of determining the dc offset of the voltage square signal refers to determining an average value of the voltage square signal in a time window.
Optionally, the function expression for averaging the square voltage signal in the time window is:
in the above-mentioned method, the step of,indicating that the square signal of the voltage is within the time windowN is the size of the time window, u 2 And (t) is a voltage squared signal.
Optionally, in step S103, the function expression of subtracting the dc bias of the voltage square signal from the voltage square signal to obtain the optimized voltage signal is:
in the above-mentioned method, the step of,represents the optimized voltage signal, u 2 (t) is the square signal of the voltage, ">Representing the average of the voltage squared signal over a time window.
Optionally, step S104 includes:
s201, removing components above direct current and second harmonic from the optimized voltage signal through band-pass filtering;
s202, performing sensitivity weighting filtering by adopting a sensitivity weighting filter;
s203, squaring the signals obtained after the weighted and filtered of the sensitivity to obtain a weighted and filtered squared signal of the sensitivity;
s204, extracting a direct current component from the sensitivity weighted filtering square signal by adopting a first-order low-pass filter;
s205, calculating flicker sensitivity S (t) according to the extracted direct current component, classifying the value of the flicker sensitivity S (t) obtained by detection from small to large, calculating the cumulative probability CPF (i) of each stage of flicker sensitivity S (t), and obtaining a short-time flicker value P according to the cumulative probability st As a result of the obtained voltage flicker detection.
Optionally, the bandwidth of the band-pass filtering in step S201 is 0.05Hz to 35Hz, and the band-pass filter used for the band-pass filtering is composed of a first-order high-pass filter with a cutoff frequency of 0.05Hz and a low-pass filter with a cutoff frequency of 35Hz, where the transfer function of the first-order high-pass filter is as follows:
in the above equation, HP(s) represents the transfer function of the first order high pass filter, s is the laplace operator,a cut-off angular frequency for the high pass filter; wherein the low pass filter is a 6 th order butterworth filter, and the transfer function is:
in the above formula, HP(s) represents the transfer function of the low-pass filter, b i Parameters for the i-th order butterworth filter, s is the laplace operator,is the cut-off angular frequency of the low pass filter.
Optionally, the transfer function of the sensitivity weighting filter in step S202 is:
in the above formula, k(s) represents the transfer function of the sensitivity weighting filter, k is a parameter, s is a Laplace operator, λ is a parameter, ω 1 ，ω 2 ，ω 3 ，ω 4 Is a parameter;
in step S203, the function expression of the square of the signal obtained by weighting and filtering the sensitivity is:
in the above, (mA) 2 cos(Ωt)) 2 Representing visual perceptionThe square signal is subjected to degree weighted filtering, m is the amplitude of amplitude-modulated wave voltage, A is the amplitude of power frequency carrier voltage, omega is the angular frequency of the amplitude-modulated wave voltage, and t is time;
the transfer function of the first-order low-pass filter in step S204 is:
HP(s)＝1/(1+n×s)，
in the above formula, HP(s) represents the transfer function of the first-order low-pass filter, s is the Laplace operator, and n is a parameter;
in step S205, calculating the flicker sensitivity S (t) from the extracted dc component means that the flicker sensitivity S (t) is obtained by multiplying the extracted dc component by 320000, and the function expression for calculating the cumulative probability CPF (i) of each stage of flicker sensitivity S (t) is:
CPF(i)＝t i /t all ，
in the above formula, CPF (i) represents the cumulative probability of the ith flicker sensitivity S (t), t i To exceed the accumulated time of the ith flicker sensitivity S (t), t all Is the total test time; determining a short-time flicker value P according to the cumulative probability st The functional expression of (2) is:
in the above, P st Is a short-time flicker value, P 0.1、 P 1 、P 3 、P 10 And P 50 The cumulative probability exceeds a preset threshold T in the detection time of the designated duration 1 、T 2 、T 3 、T 4 And T 5 Flicker sensitivity S (t).
In addition, the invention also provides a voltage flicker acceleration detection system, which comprises a microprocessor and a memory which are connected with each other, wherein the microprocessor is programmed or configured to execute the voltage flicker acceleration detection method.
Furthermore, the present invention provides a computer readable storage medium having stored therein a computer program for being programmed or configured by a microprocessor to perform the voltage flicker acceleration detection method.
Compared with the prior art, the invention has the following advantages: according to the invention, on the basis of an IEC flicker detection method, a voltage square signal is obtained by squaring a voltage signal to be detected, the direct current bias of the voltage square signal is obtained, then the direct current bias of the voltage square signal is subtracted from the voltage square signal to obtain an optimized voltage signal, and then the demodulation filtering, the visual sensitivity weighting filtering, the squaring, the smoothing weighting filtering and the statistical processing of the IEC flicker detection method are carried out to obtain a voltage flicker detection result, so that the convergence speed of a band-pass filter can be effectively increased, the problems that the convergence speed of demodulation filtering is low and the flicker detection precision is influenced in the conventional IEC flicker detection method are solved, and the detection precision is improved while the flicker detection speed is ensured.
Drawings
FIG. 1 is a schematic diagram of a basic flow of a method according to an embodiment of the present invention.
FIG. 2 is a graph showing the comparison of the effects of the method according to the embodiment of the present invention with those of the conventional method.
Detailed Description
As shown in fig. 1, the present embodiment provides a voltage flicker acceleration detection method, including:
s101, squaring a voltage signal to be detected to obtain a voltage square signal;
s102, obtaining direct current bias of a voltage square signal;
s103, subtracting the direct current bias of the voltage square signal from the voltage square signal to obtain an optimized voltage signal;
and S104, performing demodulation filtering, sensitivity weighting filtering, squaring, smoothing weighting filtering and statistical processing on the optimized voltage signal to obtain a voltage flicker detection result.
With standard flicker as an example of a voltage signal to be detected, signal frequency f 0 =50 Hz, fluctuation frequency f 1 The sampling frequency fs=400 Hz is 8.8Hz, the effective value of the signal is 57.735V, the fluctuation amplitude m=0.25%, the sampling time window length of taking single analysis data is 1 minute, namely standard flicker is sampled at the sampling rate fs=400 Hz within 1 minute.
In this embodiment, the functional expression of the voltage signal to be detected in step S101 is:
u(t)＝A(1+m*cos(Ωt))cos(ωt)，
in the above formula, u (t) represents a voltage signal to be detected at a time t, A is the amplitude of the power frequency carrier voltage, m is the amplitude of the amplitude-modulated wave voltage, Ω is the angular frequency of the amplitude-modulated wave voltage, t is the time, ω is the angular frequency of the power frequency carrier voltage; m is cos (Ω t) represents a fluctuating voltage. For standard flicker, there are:
ω＝2πf 0 /f s ，
Ω＝2πf 1 /f s ，
m＝0.25％，
wherein f 0 Representing the signal frequency, f s Represents the sampling frequency, f 1 Representing the frequency of the fluctuation.
In step S101 of this embodiment, the function expression for squaring the voltage signal to be detected to obtain the voltage squared signal is:
in the above, u 2 (t) represents a voltage square signal, A is the amplitude of the power frequency carrier voltage, m is the amplitude of the amplitude-modulated wave voltage, Ω is the angular frequency of the amplitude-modulated wave voltage, t is the time, ω is the angular frequency of the power frequency carrier voltage.
In this embodiment, the step S102 of obtaining the dc bias of the voltage square signal means obtaining the average value of the voltage square signal in the time window. Specifically, in this embodiment, the function expression for calculating the average value of the square voltage signal in the time window is:
in the above-mentioned method, the step of,represents the average value of the square signal of the voltage in a time window, N is the size of the time window, u 2 And (t) is a voltage squared signal.
In this embodiment, in step S103, the function expression of the optimized voltage signal obtained by subtracting the dc bias of the voltage square signal from the voltage square signal is:
in the above-mentioned method, the step of,represents the optimized voltage signal, u 2 (t) is the square signal of the voltage, ">Representing the average of the voltage squared signal over a time window.
In this embodiment, step S104 includes:
s201, removing components above direct current and second harmonic from the optimized voltage signal through band-pass filtering;
s202, performing sensitivity weighting filtering by adopting a sensitivity weighting filter;
s203, squaring the signals obtained after the weighted and filtered of the sensitivity to obtain a weighted and filtered squared signal of the sensitivity;
s204, extracting a direct current component from the sensitivity weighted filtering square signal by adopting a first-order low-pass filter;
s205, calculating flicker sensitivity S (t) according to the extracted direct current component, classifying the value of the flicker sensitivity S (t) obtained by detection from small to large, calculating the cumulative probability CPF (i) of each stage of flicker sensitivity S (t), and obtaining a short-time flicker value P according to the cumulative probability st As a result of the obtained voltage flicker detection.
In this embodiment, the bandwidth of the band pass filtering in step S201 is 0.05 Hz-35 Hz for filtering to remove the components above the DC and second harmonics and retain mA 2 cos (Ω), and the bandpass filter used for bandpass filtering consists of a first order high pass filter with a cutoff frequency of 0.05Hz and a low pass filter with a cutoff frequency of 35Hz, wherein the transfer function of the first order high pass filter is:
in the above equation, HP(s) represents the transfer function of the first order high pass filter, s is the laplace operator,for the cut-off angle frequency of the high-pass filter +.>At a sampling rate fs=400 Hz, the Z-transform of the first order high pass filter is:
in the above formula, z is an independent variable.
In this embodiment, the low-pass filter is a 6 th order butterworth filter, and the transfer function is:
in the above, HP% S ) Representing the transfer function of a low pass filter, b i Parameters for the i-th order butterworth filter, s is the laplace operator,is the cut-off angular frequency of the low pass filter. In this embodiment, <' > a->b 1 ＝3.864，b 2 ＝7.464，b 3 ＝9.141，b 4 ＝7.464，b 5 ＝3.864，b 6 ＝1.0。
Let the sampling rate fs=400 Hz, the Z-transform of the low-pass filter be:
wherein a is 1 ＝-3.9316，a 2 ＝6.6912，a 3 ＝-6.2495，a 4 ＝3.3605，a 5 ＝-9.8276*10 -1 ，a 6 ＝1.2179*10 -1 ，e 0 ＝1.5059*10 -4 ，e 1 ＝9.0354*10 -4 ，e 2 ＝2.2589*10 -3 ，e 3 ＝3.0118*10 -3 ，e 4 ＝2.2589*10 -3 ，e 5 ＝9.0354*10 -4 ，e 6 ＝1.5059*10 -4 The weights of the individual terms are represented.
In this embodiment, the transfer function of the sensitivity weighting filter in step S202 is:
in the above formula, k(s) represents the transfer function of the sensitivity weighting filter, k is a parameter, s is a Laplace operator, λ is a parameter, ω 1 ，ω 2 ，ω 3 ，ω 4 Is a parameter. In this embodiment, k= 1.74082, λ=2pi× 4.05981, ω 1 ＝2π*9.15494，ω 2 ＝2π*2.27979，ω 3 ＝2π*1.22535，ω 4 =2pi×21.90. In this embodiment, the center frequency of the sensitivity weighting filter is 8.8Hz in order to simulate the response of the human eye to voltage fluctuations of different frequencies. Setting a sampling rate F s =400 Hz, the Z-transform of the weighting filter is:
in the above, d 1 ＝-3.5488，d 2 ＝4.7145，d 3 ＝-2.7760，d 4 ＝6.1032*10 -1 ，c 0 ＝9.3125*10 -3 ，c 1 ＝3.2762*10 -4 ，c 2 ＝-1.8297*10 -2 ，c 3 ＝-3.2762*10 -4 ，c 4 ＝8.9848*10 -3 The weights of the individual terms are represented.
In this embodiment, the function expression of the square of the signal obtained by weighting and filtering the sensitivity in step S203 is:
in the above, (mA) 2 cos(Ωt)) 2 The method is characterized in that the method is used for representing a visual sensitivity weighted filtering square signal, m is the amplitude of amplitude-modulated wave voltage, A is the amplitude of power frequency carrier voltage, omega is the angular frequency of the amplitude-modulated wave voltage, and t is time, wherein a direct current component is required for flicker evaluation.
The purpose of the first-order low-pass filter in step S204 is to extract the dc component of the output of the sixth step, and the transfer function of the first-order low-pass filter in step S204 in this embodiment is:
HP(s)＝1/(1+n×s)，
in the above formula, HP(s) represents the transfer function of the first-order low-pass filter, s is the Laplace operator, and n is a parameter; in this embodiment, the cutoff frequency of the first-order low-pass filter is set to 0.53Hz, the time constant is 300ms, and the transfer function can be expressed as:
let the sampling rate fs=400 Hz, the Z-transform of the first order low pass filter be:
calculating flicker sensitivity S (t) from the extracted dc component in step S205 means multiplying the extracted dc component byThe flicker sensitivity S (t) is obtained, and the flicker sensitivity S (t) obtained by detection is classified from small to large, and is usually not less than 64 stages.
In this embodiment, the function expression for calculating the cumulative probability CPF (i) of each stage flicker sensitivity S (t) is:
CPF(i)＝t i /t all ，
in the above formula, CPF (i) represents the cumulative probability of the ith flicker sensitivity S (t), t i To exceed the accumulated time of the ith flicker sensitivity S (t), t all Is the total test time; determining a short-time flicker value P according to the cumulative probability st The functional expression of (2) is:
in the above, P st Is a short-time flicker value, P 0.1、 P 1 、P 3 、P 10 And P 50 The cumulative probability exceeds a preset threshold T in the detection time of the designated duration 1 、T 2 、T 3 、T 4 And T 5 Flicker sensitivity S (t). For example, as an alternative embodiment, the visibility values of more than 0.1%,1%,3%,10% and 50% respectively are removed in this example.
Fig. 2 shows a comparison of direct 0.05Hz high-pass filtering with direct current offset with the square signal of the voltage removed, and then 0.05Hz high-pass filtering, wherein the abscissa in the figure is a waveform signal, and the abscissa is time, and the waveform signal is sampled sequentially at a sampling frequency in a time window. Referring to fig. 2, as a comparison conventional method (without steps S102 and S103), in performing the 0.05Hz high-pass filtering step at S104, 11 seconds is required to converge to the effective number after the square of the sampled dataThe data before 11 seconds are all invalid data, so that the available points are few, and the calculated short-time flicker value P is calculated st 1.05; after the filtering direct current links of S102 and S103 are added by the method (shown as the method in the figure), the direct current links converge about 0.1S, namely the data of the direct current links are stabilized about 0.1 seconds, the effective data for calculation is added, and the calculated short-time flicker value P is increased st 1.01. Whereas the short flicker value P of standard flicker st 1. Therefore, the voltage flicker acceleration detection method of the embodiment can effectively accelerate the convergence speed of the band-pass filter through steps S102 and S103, solve the problems that the demodulation and filtering convergence speed of the conventional IEC flicker detection method is low, and the accuracy of flicker detection is affected, and improve the accuracy of detection while ensuring the flicker detection speed.
In addition, the embodiment also provides a voltage flicker acceleration detection system, which comprises a microprocessor and a memory which are connected with each other, wherein the microprocessor is programmed or configured to execute the voltage flicker acceleration detection method. Furthermore, the present embodiment also provides a computer-readable storage medium having stored therein a computer program for being programmed or configured by a microprocessor to perform the voltage flicker acceleration detection method.
It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein. The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may 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, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks. These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above examples, and all technical solutions belonging to the concept of the present invention belong to the protection scope of the present invention. It should be noted that modifications and adaptations to the present invention may occur to one skilled in the art without departing from the principles of the present invention and are intended to be within the scope of the present invention.
Claims (10)
1. The voltage flicker acceleration detection method is characterized by comprising the following steps of:
s101, squaring a voltage signal to be detected to obtain a voltage square signal;
s102, obtaining direct current bias of a voltage square signal;
s103, subtracting the direct current bias of the voltage square signal from the voltage square signal to obtain an optimized voltage signal;
and S104, performing demodulation filtering, sensitivity weighting filtering, squaring, smoothing weighting filtering and statistical processing on the optimized voltage signal to obtain a voltage flicker detection result.
2. The method for detecting voltage flicker acceleration according to claim 1, wherein the functional expression of the voltage signal to be detected in step S101 is:
u(t)＝A(1+m*cos(Ωt))cos(ωt)，
in the above formula, u (t) represents a voltage signal to be detected at a time t, A is the amplitude of the power frequency carrier voltage, m is the amplitude of the amplitude-modulated wave voltage, Ω is the angular frequency of the amplitude-modulated wave voltage, t is the time, ω is the angular frequency of the power frequency carrier voltage; m is cos (Ω t) represents a fluctuating voltage.
3. The method for detecting voltage flicker acceleration according to claim 1, wherein the square of the voltage signal to be detected in step S101 is expressed as a function of the square signal of the voltage:
in the above, u 2 (t) represents a voltage square signal, A is the amplitude of the power frequency carrier voltage, m is the amplitude of the amplitude-modulated wave voltage, Ω is the angular frequency of the amplitude-modulated wave voltage, t is the time, ω is the angular frequency of the power frequency carrier voltage.
4. The method for detecting voltage flicker acceleration according to claim 1, wherein the step S102 of obtaining the dc bias of the voltage square signal is to obtain an average value of the voltage square signal in a time window.
5. The method for detecting voltage flicker acceleration according to claim 4, wherein the function expression for averaging the square voltage signal in the time window is:
in the above-mentioned method, the step of,represents the average value of the square signal of the voltage in a time window, N is the size of the time window, u 2 And (t) is a voltage squared signal.
6. The method for detecting voltage flicker acceleration according to claim 1, wherein in step S103, the dc bias obtained by subtracting the voltage square signal from the voltage square signal is expressed as a function of the optimized voltage signal:
in the above-mentioned method, the step of,represents the optimized voltage signal, u 2 (t) is the square signal of the voltage, ">Representing the average of the voltage squared signal over a time window.
7. The method of detecting voltage flicker acceleration according to any one of the claims 1-5, characterized in, that step S104 comprises:
s201, removing components above direct current and second harmonic from the optimized voltage signal through band-pass filtering;
s202, performing sensitivity weighting filtering by adopting a sensitivity weighting filter;
s203, squaring the signals obtained after the weighted and filtered of the sensitivity to obtain a weighted and filtered squared signal of the sensitivity;
s204, extracting a direct current component from the sensitivity weighted filtering square signal by adopting a first-order low-pass filter;
s205, calculating flicker sensitivity S (t) according to the extracted direct current component, classifying the value of the flicker sensitivity S (t) obtained by detection from small to large, calculating the cumulative probability CPF (i) of each stage of flicker sensitivity S (t), and obtaining a short-time flicker value P according to the cumulative probability st As a result of the obtained voltage flicker detection.
8. The method for accelerating voltage flicker detection according to claim 7, wherein the bandwidth of the band-pass filter in step S201 is 0.05Hz to 35Hz, and the band-pass filter used for the band-pass filter is composed of a first-order high-pass filter with a cutoff frequency of 0.05Hz and a low-pass filter with a cutoff frequency of 35Hz, wherein the transfer function of the first-order high-pass filter is:
in the above equation, HP(s) represents the transfer function of the first order high pass filter, s is the laplace operator,a cut-off angular frequency for the high pass filter; wherein the low pass filter is a 6 th order butterworth filter, and the transfer function is:
in the above formula, HP(s) represents the transfer function of the low-pass filter, b i Parameters for the i-th order butterworth filter, s is the laplace operator,a cut-off angular frequency that is a low pass filter;
the transfer function of the sensitivity weighting filter in step S202 is:
in the above formula, k(s) represents the transfer function of the sensitivity weighting filter, k is a parameter, s is a Laplace operator, λ is a parameter, ω 1 ，ω 2 ，ω 3 ，ω 4 Is a parameter;
in step S203, the function expression of the square of the signal obtained by weighting and filtering the sensitivity is:
in the above, (mA) 2 cos(Ωt)) 2 The square signal of the visual sensitivity weighted filtering is the amplitude of amplitude-modulated wave voltage, A is the amplitude of power frequency carrier voltage, omega is the angular frequency of the amplitude-modulated wave voltage, and t is time;
the transfer function of the first-order low-pass filter in step S204 is:
HP(s)＝1/(1+n×s)，
in the above formula, HP(s) represents the transfer function of the first-order low-pass filter, s is the Laplace operator, and n is a parameter;
in step S205, calculating the flicker sensitivity S (t) from the extracted dc component means that the flicker sensitivity S (t) is obtained by multiplying the extracted dc component by 320000, and the function expression for calculating the cumulative probability CPF (i) of each stage of flicker sensitivity S (t) is:
CPF(i)＝t i /t all ，
in the above formula, CPF (i) represents the cumulative probability of the ith flicker sensitivity S (t), t i To exceed the accumulated time of the ith flicker sensitivity S (t), t all Is the total test time; determining a short-time flicker value P according to the cumulative probability st The functional expression of (2) is:
in the above, P st Is a short-time flicker value, P 0. 、P 1 、P 3 、P 10 And P 50 The cumulative probability exceeds a preset threshold T in the detection time of the designated duration 1 、T 2 、T 3 、T 4 And T 5 Flicker sensitivity S (t).
9. A voltage flicker acceleration detection system comprising a microprocessor and a memory connected to each other, wherein the microprocessor is programmed or configured to perform the voltage flicker acceleration detection method of any one of claims 1 to 8.
10. A computer readable storage medium having a computer program stored therein, wherein the computer program is for being programmed or configured by a microprocessor to perform the voltage flicker acceleration detection method of any one of claims 1-8.
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