CN107271753B - Voltage flicker detection method and device - Google Patents
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Abstract
The invention provides a voltage flicker detection method and device. The method is applied to a digital flicker detector, and a comparison table of amplitude modulation wave frequency and voltage fluctuation value is stored in the digital flicker detector, and the method comprises the following steps: and detecting the voltage signals of the multi-amplitude modulation wave frequency to obtain the voltage signals of the multi-amplitude modulation wave frequency, and analyzing and calculating the voltage signals of the multi-amplitude modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude modulation wave frequency. And calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result. Therefore, the voltage flicker detection process is simplified, the calculated amount is small, the voltage flicker detection result can be quickly obtained, the detection efficiency and the measurement precision are improved, the detection error is reduced, and the method has good engineering application and theoretical analysis prospects.
Description
Technical Field
The invention relates to the technical field of voltage detection, in particular to a voltage flicker detection method and device.
Background
New energy grid-connected power generation represented by wind power generation and photovoltaic power generation has become an unblocked development trend of a novel power system. The output power of renewable energy sources such as solar energy and wind energy has strong fluctuation, and voltage fluctuation and flicker at the public connection point of a power grid are easily caused. And the voltage flicker phenomenon can cause harm to the life and work of people. The flickering of the illumination light source can cause fatigue to the vision of people and damage to the eyes of people. Voltage flicker influences the normal operating of motor, influences the work efficiency of enterprise.
At present, the voltage fluctuation detection methods commonly used internationally mainly include a squaring detection method, a rectifying detection method and an effective value detection method. The digital implementation of the rectification detection method and the effective value detection method is difficult, and the sudden change and non-stable voltage flicker envelope signals cannot be effectively detected.
The IEC recommended square detection method is specified in an analog mode, no clear implementation method is provided for each link, actual numerical calculation cannot be performed, and a digital filter of each link needs to be designed according to the IEC flicker measurement principle during application.
In the prior art, numerical calculation is usually performed by using a digital flicker meter, but the calculation process is complicated and the measurement error is large.
Disclosure of Invention
In order to overcome the above-mentioned deficiencies in the prior art, the present invention provides a voltage flicker detection method and device, which simplifies the voltage flicker detection process, has small calculation amount, can quickly obtain the voltage flicker detection result, improves the detection efficiency, and reduces the detection error.
The first objective of the present invention is to provide a voltage flicker detection method, which is applied to a digital flicker detector, wherein a comparison table of amplitude modulation wave frequency and voltage fluctuation value is stored in the digital flicker detector, and the method comprises:
detecting the voltage signals of the multi-amplitude modulation wave frequency to obtain the voltage signals of the multi-amplitude modulation wave frequency, and analyzing and calculating the voltage signals of the multi-amplitude modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude modulation wave frequency;
and calculating the voltage fluctuation value of the multi-amplitude-modulation-wave frequency according to the comparison table of the amplitude-modulation-wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result.
A second object of the present invention is to provide a voltage flicker detection apparatus, which is applied to a digital flicker detector, wherein a comparison table of an amplitude modulation frequency and a voltage fluctuation value is stored in the digital flicker detector, and the apparatus includes:
the detection calculation module is used for detecting the voltage signals with the multiple amplitude modulation wave frequencies to obtain the voltage signals with the multiple amplitude modulation wave frequencies, and analyzing and calculating the voltage signals with the multiple amplitude modulation wave frequencies according to a dynamic vector method to obtain voltage fluctuation values of the multiple amplitude modulation wave frequencies;
and the calculation processing module is used for calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result.
Compared with the prior art, the invention has the following beneficial effects:
the invention provides a voltage flicker detection method and device. The method is applied to a digital flicker detector, and a comparison table of amplitude modulation wave frequency and voltage fluctuation value is stored in the digital flicker detector, and the method comprises the following steps: and detecting the voltage signals of the multi-amplitude modulation wave frequency to obtain the voltage signals of the multi-amplitude modulation wave frequency, and analyzing and calculating the voltage signals of the multi-amplitude modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude modulation wave frequency. And calculating the voltage fluctuation value of the multi-amplitude-modulation-wave frequency according to the comparison table of the amplitude-modulation-wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result. Therefore, the voltage flicker detection process is simplified, the calculated amount is small, the voltage flicker detection result can be quickly obtained, the detection efficiency and the measurement precision are improved, the detection error is reduced, and the method has good engineering application and theoretical analysis prospects.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
Fig. 1 is a block diagram of a digital flicker detector according to a preferred embodiment of the present invention.
Fig. 2 is a flowchart illustrating steps of a voltage flicker detection method according to a first embodiment of the present invention.
FIG. 3 is a second flowchart illustrating the steps of the voltage flicker detection method according to the first embodiment of the present invention.
Fig. 4 is a flowchart illustrating sub-steps of step S110 shown in fig. 3 according to a first embodiment of the present invention.
Fig. 5 is a flowchart of sub-steps of the sub-step S111 shown in fig. 4 according to the first embodiment of the present invention.
Fig. 6 is a flowchart illustrating sub-steps of step S120 shown in fig. 2 according to a first embodiment of the present invention.
Fig. 7 is a flowchart illustrating sub-steps of step S130 shown in fig. 2 according to a first embodiment of the present invention.
Fig. 8 is a functional block diagram of a voltage flicker detection apparatus according to a second embodiment of the present invention.
Icon: 100-digital flicker detector; 110-a memory; 120-a processor; 200-voltage flicker detection means; 210-a detection calculation module; 220-calculation processing module.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.
Referring to fig. 1, fig. 1 is a block diagram of a digital flicker detector 100 according to a preferred embodiment of the invention. The digital flicker detector 100 includes a memory 110, a voltage flicker detector 200, and a processor 120.
The memory 110 and the processor 120 are electrically connected to each other directly or indirectly to achieve data transmission or interaction. For example, the components may be electrically connected to each other via one or more communication buses or signal lines. The memory 110 stores therein a voltage flicker detection device 200, the voltage flicker detection device 200 includes at least one software functional module which can be stored in the memory 110 in the form of software or firmware (firmware), and the processor 120 executes various functional applications and data processing by running the software programs and modules stored in the memory 110.
The Memory 110 may be, but is not limited to, a Random Access Memory (RAM), a Read Only Memory (ROM), a Programmable Read-Only Memory (PROM), an Erasable Read-Only Memory (EPROM), an electrically Erasable Read-Only Memory (EEPROM), and the like. The memory 110 is used for storing a program, and the processor 120 executes the program after receiving an execution instruction. Further, the software programs and modules within the memory 110 may also include an operating system, which may include various software components and/or drivers for managing system tasks (e.g., memory management, storage device control, power management, etc.), and may communicate with various hardware or software components to provide an operating environment for other software components.
The processor 120 may be an integrated circuit chip having signal processing capabilities. The Processor 120 may be a general-purpose Processor including a Central Processing Unit (CPU), a Network Processor (NP), and the like. The various methods, steps and logic blocks disclosed in the embodiments of the present invention may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
It will be appreciated that the configuration depicted in FIG. 1 is merely illustrative and that the digital flicker detector 100 may include more or fewer components than shown in FIG. 1, or may have a different configuration than shown in FIG. 1. The components shown in fig. 1 may be implemented in hardware, software, or a combination thereof.
First embodiment
Referring to fig. 2, fig. 2 is a flowchart illustrating a voltage flicker detection method according to a first embodiment of the present invention. The method is applied to the digital flicker detector 100, and a comparison table of amplitude modulation wave frequency and voltage fluctuation value is stored in the digital flicker detector 100. The following describes the specific flow of the voltage flicker detection method in detail.
And step S120, detecting the voltage signals of the multi-amplitude modulation wave frequency to obtain the voltage signals of the multi-amplitude modulation wave frequency, and analyzing and calculating the voltage signals of the multi-amplitude modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude modulation wave frequency.
And step S130, calculating the voltage fluctuation value of the multi-amplitude-modulation-wave frequency according to the comparison table of the amplitude-modulation-wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result.
Referring to fig. 3, fig. 3 is a second flowchart illustrating a voltage flicker detection method according to a first embodiment of the invention. The method further comprises the following steps:
step S110, detecting a plurality of voltage signals with different single amplitude modulation wave frequencies to obtain corresponding voltage signals, and analyzing and calculating the voltage signals according to a dynamic vector method to obtain a comparison table of the amplitude modulation wave frequencies and the voltage fluctuation values.
In this embodiment, in order to establish a comparison table of the amplitude modulation wave frequency and the voltage fluctuation value, it is necessary to perform a plurality of times of detection of the voltage signal condition of a single amplitude modulation wave frequency for a plurality of different amplitude modulation wave frequencies.
Referring to fig. 4, fig. 4 is a flowchart illustrating sub-steps of step S110 shown in fig. 3 according to a first embodiment of the present invention. The step S110 includes a substep S111 and a substep S112.
And a substep S111 of respectively detecting the voltage signal of each single amplitude modulation wave frequency to obtain a corresponding voltage signal, and analyzing and calculating the voltage signals according to a dynamic vector method to obtain a comparison relation between the amplitude modulation wave frequency and the voltage fluctuation value.
Referring to fig. 5, fig. 5 is a flowchart illustrating sub-steps S111 shown in fig. 4 according to a first embodiment of the present invention. The sub-step S111 includes sub-step S1110, sub-step S1111, and sub-step S1112.
In the sub-step S1110, when detecting the voltage signal with the single amplitude modulation wave frequency each time, the voltage signal with the currently detected amplitude modulation wave frequency is collected in a preset period according to a preset sampling time interval, and a root mean square value is calculated for the collected voltage signal to obtain a root mean square sequence.
In this embodiment, the acquired voltage signal is a voltage signal acquired at a new energy grid-connected position, where the new energy grid-connected position refers to a connection position of photovoltaic or wind power and a power grid.
In this embodiment, the digital flicker detector 100 collects the voltage signal of the amplitude modulated wave frequency currently detected in a preset period (for example, 10s) according to a preset sampling time interval (for example, 20ms), and performs preliminary processing on each collected voltage signal to obtain a voltage signal instantaneous value:
u(t)=A(1+mcos2πfm)cos2πfst
the digital flicker detector 100 calculates a Root Mean Square (RMS) value of the instantaneous voltage signal to obtain a Root mean square sequence (e.g., y (t)), where the expression of the Root mean square sequence y (t) is as follows:
wherein A is the amplitude of the power frequency carrier voltage, fsFrequency of power frequency carrier voltage, fsAnd m is the relative amplitude of the amplitude modulated wave voltage, namely 50 Hz. f. ofmT is 0.02s, which is the frequency of the amplitude modulated wave voltage,
in this embodiment, Root Mean Square (RMS), also called Root Mean Square (RMS), is one of the most common mathematical methods for defining the effective voltage or Current of an Alternating Current (AC). The order of calculation is first the square, then the average and finally the square.
And a substep S1111, which is to perform Fourier transform on the root mean square sequence according to a dynamic vector method to obtain a dynamic vector.
In this embodiment, the digital flicker detector 100 adopts a dynamic vector method to obtain a result of fourier transform of the root-mean-square sequence y (t), so as to obtain a K-th output value of y (t), i.e. a K-th dynamic vector of y (t), where the expression is as follows:
wherein, the sampling time interval is 20ms, and the preset period is T0Obtained as 10sThe frequency resolution is 0.1HZ, i.e. the fundamental frequency after fourier transformation is 0.1 HZ.
And a substep S1112, which brings the dynamic vector into a preset formula for calculation to obtain a voltage fluctuation value corresponding to the amplitude modulation wave frequency.
In this embodiment, the digital flicker detector 100 substitutes the dynamic vector into a preset formula for calculation, so as to obtain an RMS voltage fluctuation value Δ U that makes the instantaneous flicker severity indicator S equal to 1 at the currently detected single amplitude modulated wave frequencyrms. The subjective visual response of the human body to the luminance fluctuation caused by the voltage fluctuation is called instantaneous flicker visibility, and the unit of measurement of the instantaneous flicker visibility is usually 50%, that is, the instantaneous flicker visibility S is 1.
In this embodiment, the preset formula may be a frequency amplitude relative value obtained by using a direct current component (0-order dynamic vector) as a reference value, where the frequency amplitude relative value is an RMS fluctuation value Δ U corresponding to when S is equal to 1 at a currently detected single amplitude modulation wave frequencyrmsHalf of that. The calculation formula is as follows:
wherein, wm.i=2πfiFor the angular frequency, denominator of the ith amplitude-modulated wave<y>0Represents the 0 th order dynamic vector, i.e. the direct current component after Fourier transformation.<y>fi/0.1Fi in (1) represents flicker after Fourier transformFrequency due to fundamental frequency of 0.1Hz, i.e.<y>k=<y>fi/0.1。
In this embodiment, the relative value of the frequency amplitude can be obtained by calculating the equations on the left and right sides of the first equal sign in the above equationMultiplying the relative frequency-amplitude value by 2 to obtain Bfi,BfiFor amplitude modulation of wave frequency fiRMS voltage fluctuation value (i.e., Δ U) such that S is 1rms). Therefore, the comparison relation between the current amplitude modulation wave frequency and the voltage fluctuation value can be obtained.
In the embodiment, the dynamic vector method is adopted to carry out the new energy grid-connected voltage flicker analysis, a specific analytical expression is given, and a new direction is provided for the digital flicker detection research.
And a substep S112 of generating and storing a comparison table of the amplitude modulation wave frequency and the voltage fluctuation value according to the obtained comparison relationship of the amplitude modulation wave frequencies and the voltage fluctuation values.
In this embodiment, the digital flicker detector 100 generates and stores a comparison table of the amplitude modulation frequency and the voltage fluctuation value according to the obtained comparison relationship between the amplitude modulation frequencies and the voltage fluctuation values. Based on the above description, the mapping table of the amplitude modulation wave frequency and the voltage fluctuation value can be the amplitude modulation wave frequency (f) and the RMS voltage fluctuation value (Δ U)rms) The comparison table (2).
In the embodiment, the human eye can only sense the voltage fluctuation within 0.05-35 Hz, and the direct current and the frequency above 35Hz do not need to be recorded in the table.
Step S120 in fig. 2 is explained based on the above description.
Referring to fig. 6, fig. 6 is a flowchart illustrating sub-steps of step S120 shown in fig. 2 according to a first embodiment of the present invention. The step S120 includes a substep S121 and a substep S122.
And a substep S121, collecting the voltage signal of the multi-amplitude modulation wave frequency, modulating and converting the collected voltage signal of the multi-amplitude modulation wave frequency, and performing square root value calculation on the modulated and converted voltage signal to obtain a square root sequence of the multi-amplitude modulation wave frequency.
In this embodiment, the digital flicker detector 100 collects voltage signals with multiple am wave frequencies at a new energy grid-connected location, and modulates and converts the voltage signals into voltage signals with a sinusoidal multiple am wave form, where the formula is as follows:
wherein U is the amplitude of the power frequency carrier voltage, K is the total number of amplitude modulated waves, miIs the relative amplitude, f, of the ith amplitude modulated waveiFrequency of the i-th amplitude modulation wave, fsysThe frequency of the power frequency carrier voltage.
In this embodiment, the operation of performing the square root value calculation on the modulated and converted voltage signal to obtain the square root sequence of the multiple am wave frequencies is the same as the operation at the single am wave frequency, and specific reference may be made to the above description of the sub-step S1110.
And a substep S122, calculating the root-mean-square sequence of the multi-amplitude-modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude-modulation wave frequency.
In this embodiment, the digital flicker detector 100 calculates the root-mean-square sequence of the multi-am frequency according to a dynamic vector method to obtain a voltage fluctuation value (a) of the multi-am frequencyfi) The operation of processing the root-mean-square sequence of multiple am frequencies according to the motion vector method is the same as the operation at a single am frequency, and reference may be made to the description of sub-steps S1111 and S1112 in the above.
Step S130 in fig. 2 is explained based on the above description.
Referring to fig. 7, fig. 7 is a flowchart illustrating sub-steps of step S130 shown in fig. 2 according to a first embodiment of the present invention. The step S130 includes a sub-step S131 and a sub-step S132.
And a substep S131, calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain the instantaneous flicker value corresponding to each amplitude modulation wave frequency.
In this embodiment, the digital flicker detector 100 obtains a voltage fluctuation value (B) corresponding to each amplitude modulation wave frequency by looking up a pre-stored comparison table of amplitude modulation wave frequencies and voltage fluctuation valuesfi). The digital flicker detector 100 queries each voltage fluctuation value (B)fi) And voltage fluctuation values (A) of multiple AM frequenciesfi) Carrying into a preset flicker value formula for calculation to obtain a corresponding instantaneous flicker value (S)fi). The specific formula is as follows:
wherein S isfiIs that the amplitude modulation wave has a frequency fiInstantaneous flicker value under component.
In this embodiment, the amplitude modulation wave frequency within the maximum frequency range (amplitude modulation wave frequency between 0.05 HZ and 35 HZ) of human eyes to observe the voltage flicker can be obtained by looking up the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain the voltage fluctuation value (B) corresponding to each amplitude modulation wave frequencyfi). Thus, the instantaneous flicker value (S) can be calculated quicklyfi) And the detection speed is accelerated.
In this embodiment, when the multi-amplitude modulation wave frequency voltage flicker detection is performed, the data in the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value obtained by the dynamic vector method in the step S110 may be directly called for analysis and calculation, so as to accelerate the detection speed, reduce the damage caused by the voltage flicker, reduce the error of the voltage flicker detection algorithm, and improve the voltage flicker measurement accuracy.
And a substep S132, summing the plurality of instantaneous flicker values, and performing root-opening calculation to obtain a short-time flicker value.
In this embodiment, the digital flicker detector 100 can detect a plurality of instantaneous flicker values (S)fi) Summing to obtain total instantaneous flickerValue (S), the summation formula is as follows:
the digital flicker detector 100 performs root-opening calculation on the total instantaneous flicker value (S) to obtain a short-time flicker value (P)st). For periodically stable voltage fluctuation, the short-time flicker value calculation formula is as follows:
in the embodiment, the dynamic vector is applied to the monitoring and analyzing of the voltage flicker of the power grid, the limit of quasi-steady state assumption is broken through, the dynamic change of the phasor amplitude is considered, the characteristics of small calculated amount and clear physical concept of the traditional vector method are achieved, and the accuracy of electromagnetic transient calculation is also considered to a certain extent.
Second embodiment
Referring to fig. 8, fig. 8 is a functional block diagram of a voltage flicker detection apparatus 200 according to a second embodiment of the present invention. The voltage flicker detection apparatus 200 is applied to the digital flicker detector 100. The device comprises: a detection calculation module 210 and a calculation processing module 220.
The detection and calculation module 210 is configured to detect the voltage signal with multiple amplitude modulation wave frequencies to obtain the voltage signal with multiple amplitude modulation wave frequencies, and analyze and calculate the voltage signal with multiple amplitude modulation wave frequencies according to a dynamic vector method to obtain a voltage fluctuation value with multiple amplitude modulation wave frequencies.
In the present embodiment, the detection calculation module 210 is configured to perform step S120 in fig. 2, and the detailed description about the detection calculation module 210 may refer to the description of step S120 in fig. 2.
And the calculation processing module 220 is configured to perform calculation processing on the voltage fluctuation value of the multiple amplitude modulation wave frequencies according to the comparison table of the amplitude modulation wave frequencies and the voltage fluctuation value to obtain a voltage flicker detection result.
In the present embodiment, the calculation processing module 220 is configured to execute step S130 in fig. 2, and the detailed description about the calculation processing module 220 may refer to the description of step S130 in fig. 2.
The detection and calculation module 210 is further configured to detect a plurality of voltage signals with different single amplitude modulation wave frequencies to obtain corresponding voltage signals, and analyze and calculate the voltage signals according to a dynamic vector method to obtain a comparison table of the amplitude modulation wave frequencies and the voltage fluctuation values.
In this embodiment, the detection calculation module 210 is further configured to execute step S110 in fig. 3, and the detailed description about the detection calculation module 210 may also refer to the description about step S110 in fig. 3.
In summary, the present invention provides a voltage flicker detection method and apparatus. The method is applied to a digital flicker detector, and a comparison table of amplitude modulation wave frequency and voltage fluctuation value is stored in the digital flicker detector, and the method comprises the following steps: and detecting the voltage signals of the multi-amplitude modulation wave frequency to obtain the voltage signals of the multi-amplitude modulation wave frequency, and analyzing and calculating the voltage signals of the multi-amplitude modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude modulation wave frequency. And calculating the voltage fluctuation value of the multi-amplitude-modulation-wave frequency according to the comparison table of the amplitude-modulation-wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result.
Therefore, the voltage flicker detection process is simplified, the calculated amount is small, the voltage flicker detection result can be quickly obtained, the detection efficiency and the measurement precision are improved, the detection error is reduced, and the method has good engineering application and theoretical analysis prospects.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. A voltage flicker detection method is applied to a digital flicker detector, and is characterized in that a comparison table of amplitude modulation wave frequency and voltage fluctuation value is stored in the digital flicker detector, and the method comprises the following steps:
detecting the voltage signals of the multi-amplitude modulation wave frequency to obtain the voltage signals of the multi-amplitude modulation wave frequency, and analyzing and calculating the voltage signals of the multi-amplitude modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude modulation wave frequency;
calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result;
detecting a plurality of voltage signals with different single amplitude modulation wave frequencies to obtain corresponding voltage signals, and analyzing and calculating the voltage signals according to a dynamic vector method to obtain a comparison table of the amplitude modulation wave frequencies and the voltage fluctuation values;
respectively detecting each voltage signal with single amplitude modulation wave frequency to obtain a corresponding voltage signal, and analyzing and calculating the voltage signals according to a dynamic vector method to obtain a comparison relation between the amplitude modulation wave frequency and a voltage fluctuation value;
generating and storing a comparison table of the amplitude modulation wave frequency and the voltage fluctuation value according to the obtained comparison relationship of the amplitude modulation wave frequencies and the voltage fluctuation values;
the method comprises the following steps of respectively detecting voltage signals of each single amplitude modulation wave frequency to obtain corresponding voltage signals, analyzing and calculating the voltage signals according to a dynamic vector method to obtain a comparison relation between the amplitude modulation wave frequency and a voltage fluctuation value, wherein the comparison relation comprises the following steps: when a voltage signal with a single amplitude modulation wave frequency is detected each time, acquiring the voltage signal with the currently detected amplitude modulation wave frequency in a preset period according to a preset sampling time interval, and performing square root value calculation on the acquired voltage signal to obtain a square root sequence;
performing Fourier transform on the root mean square sequence according to a dynamic vector method to obtain a dynamic vector;
and substituting the dynamic vector into a preset formula for calculation to obtain a voltage fluctuation value corresponding to the amplitude modulation wave frequency.
2. The method as claimed in claim 1, wherein the step of detecting the voltage signal of the multi-am frequency to obtain the voltage signal of the multi-am frequency, and the step of analyzing and calculating the voltage signal of the multi-am frequency according to the dynamic vector method to obtain the voltage fluctuation value of the multi-am frequency comprises:
collecting voltage signals of multiple amplitude modulation wave frequencies, modulating and converting the collected voltage signals of the multiple amplitude modulation wave frequencies, and performing square mean root value calculation on the modulated and converted voltage signals to obtain a square mean root sequence of the multiple amplitude modulation wave frequencies;
and calculating the root mean square sequence of the multi-amplitude modulation wave frequency according to a dynamic vector method to obtain a voltage fluctuation value of the multi-amplitude modulation wave frequency.
3. The method according to claim 1 or 2, wherein the step of calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain the voltage flicker detection result comprises:
calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain an instantaneous flicker value corresponding to each amplitude modulation wave frequency;
and summing the plurality of instantaneous flicker values, and carrying out root-opening calculation to obtain a short-time flicker value.
4. The method as claimed in claim 3, wherein the step of calculating the voltage fluctuation value of the multiple amplitude modulation wave frequencies according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain the instantaneous flicker value corresponding to each amplitude modulation wave frequency comprises:
inquiring a comparison table of amplitude modulation wave frequency and voltage fluctuation value to obtain a voltage fluctuation value corresponding to each amplitude modulation wave frequency;
and (4) bringing each voltage fluctuation value and the voltage fluctuation value of the multi-amplitude modulation wave frequency obtained by query into a preset flicker value formula for calculation to obtain corresponding instantaneous flicker values.
5. A voltage flicker detection device is applied to a digital flicker detector, and is characterized in that a comparison table of amplitude modulation wave frequency and voltage fluctuation value is stored in the digital flicker detector, and the device comprises:
the detection calculation module is used for detecting the voltage signals with the multiple amplitude modulation wave frequencies to obtain the voltage signals with the multiple amplitude modulation wave frequencies, and analyzing and calculating the voltage signals with the multiple amplitude modulation wave frequencies according to a dynamic vector method to obtain voltage fluctuation values of the multiple amplitude modulation wave frequencies;
the calculation processing module is used for calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain a voltage flicker detection result;
the detection calculation module is also used for detecting a plurality of voltage signals with different single amplitude modulation wave frequencies to obtain corresponding voltage signals, and analyzing and calculating the voltage signals according to a dynamic vector method to obtain a comparison table of the amplitude modulation wave frequencies and the voltage fluctuation values;
the detection calculation module is used for respectively detecting the voltage signal of each single amplitude modulation wave frequency to obtain a corresponding voltage signal, and analyzing and calculating the voltage signal according to a dynamic vector method to obtain a comparison relation between the amplitude modulation wave frequency and a voltage fluctuation value;
generating and storing a comparison table of the amplitude modulation wave frequency and the voltage fluctuation value according to the obtained comparison relationship of the amplitude modulation wave frequencies and the voltage fluctuation values;
the detection calculation module is specifically configured to detect each voltage signal with a single amplitude modulation wave frequency to obtain a corresponding voltage signal, and analyze and calculate the voltage signal according to a dynamic vector method to obtain a comparison relationship between the amplitude modulation wave frequency and a voltage fluctuation value, and includes: when a voltage signal with a single amplitude modulation wave frequency is detected each time, acquiring the voltage signal with the currently detected amplitude modulation wave frequency in a preset period according to a preset sampling time interval, and performing square root value calculation on the acquired voltage signal to obtain a square root sequence; performing Fourier transform on the root mean square sequence according to a dynamic vector method to obtain a dynamic vector; and substituting the dynamic vector into a preset formula for calculation to obtain a voltage fluctuation value corresponding to the amplitude modulation wave frequency.
6. The apparatus according to claim 5, wherein the means for calculating and processing the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain the voltage flicker detection result comprises:
calculating the voltage fluctuation value of the multi-amplitude modulation wave frequency according to the comparison table of the amplitude modulation wave frequency and the voltage fluctuation value to obtain an instantaneous flicker value corresponding to each amplitude modulation wave frequency;
and summing the plurality of instantaneous flicker values, and carrying out root-opening calculation to obtain a short-time flicker value.
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