Arc light transmitting detection method with self-checking function

Abstract

The invention relates to the technical field of arc light protection, in particular to an arc light transmitting detection method with a self-checking function. The method comprises the following steps: acquiring an interested frequency of a short-time window corresponding to an optical signal of arc light, analyzing an energy dissipation multiplying power of a historical short-time window, and determining a signal-to-noise ratio by combining the interested frequency of the current short-time window; screening out a calibration window from the short-time window of the optical signal; the membership degree of the minimum instantaneous power position to the arc stable section and the arc ignition end is determined, and the membership direction is determined based on the membership degree; determining the position of the minimum instantaneous power as a reset point estimation error of a phase reset point; and determining an arc light ignition position in the calibration window according to the membership direction and the reset point estimation error, and obtaining a time delay value to divide an arc light ignition-extinguishing period. According to the method, the real arc light ignition-extinguishing period is determined, the characteristic information of the arc light signal can be reserved to the maximum extent, and the transmitting quality and information effectiveness of the arc light signal are improved.

Description

Technical Field

[0001] The invention relates to the technical field of arc protection, and in particular to an arc transmission detection method with a self-checking function. Background Art

[0002] Arc transmitter is an important sensor device widely used in the fields of power, industrial automation, etc. It is mainly used to detect arc phenomena in power systems and convert them into standard current, voltage and other signals for transmission. However, in actual applications, due to environmental changes, equipment aging, external interference and other factors, arc transmitters may experience performance degradation, failure or output signal distortion.

[0003] The formation of an arc usually requires current to pass through the air or other media between high voltages, generating high temperatures and arcs. The arc formation and duration are unstable. Therefore, when an arc occurs, the light signal and the circuit zero-crossing cycle are not synchronized, making it difficult to determine the true arc ignition-extinguishing cycle. Frequent load switching in AC circuits will introduce a lot of noise, including other external light sources, electromagnetic interference, etc., which further confuses the arc information. When denoising the signal, the arc signal segment may be indiscriminately smoothed, resulting in loss of effective information. Summary of the invention

[0004] In order to solve the technical problem that it is difficult to determine the true arc ignition-extinguishing cycle due to the non-synchronization of the zero-crossing cycle and the arc ignition-extinguishing cycle of the AC circuit, the purpose of the present invention is to provide an arc transmission detection method with a self-checking function. The technical solution adopted is as follows: In a first aspect, an embodiment of the present invention provides an arc transmission detection method with a self-checking function, the method comprising: Acquire the light signal of the arc light, and analyze and obtain the frequencies of interest in different short-time windows corresponding to the light signal, wherein the frequencies of interest are periodic frequency components; Analyze the energy dissipation ratio of the historical short-time window and determine the signal-to-noise ratio by combining it with the frequency of interest in the current short-time window; According to the signal-to-noise ratio, a calibration window is selected from different short-time windows of the optical signal; according to the relative relationship between the minimum instantaneous power position in the calibration window and the centroid of the adjacent short-time window, the membership of the minimum instantaneous power position to the arc stable section and to the arc ignition end is determined respectively, and the membership direction is determined based on the membership; Compare the common frequencies and newly added frequencies on the left and right sides of the minimum instantaneous power position to determine the reset point estimation error of the phase reset point with the minimum instantaneous power position as the phase reset point; determine the arc ignition position within the calibration window based on the subordinate direction and the reset point estimation error, and obtain the time delay value; divide the arc ignition-extinguishing cycle based on the time delay value.

[0005] Preferably, the method for acquiring the frequencies of interest in different short-time windows corresponding to the optical signal is: Obtain short-time windows of persistent mutations in different short-time windows corresponding to the signal; Taking any two adjacent short-time windows in the short-time window of continuous mutation as the target adjacent short-time windows, after deleting the same frequency components in any one or more amplitude spectra in the target adjacent short-time windows, the average value of the cross-correlation function of the amplitude spectrum of each short-time window in the previous short-time window and the next short-time window in the target adjacent short-time window is calculated; the average value of the cross-correlation function is normalized to obtain the periodic characteristics of the target adjacent short-time windows; The same frequency components in the target adjacent short-time window are continuously deleted and retained until the periodic characteristic of the target adjacent short-time window reaches the maximum, and the retained frequency components that are not deleted are used as the frequencies of interest of the next short-time window in the target adjacent short-time window.

[0006] Preferably, the analyzing the energy dissipation factor of the historical short-time window and combining it with the frequency of interest of the current short-time window to determine the signal-to-noise ratio includes: The total arc light signal energy in the short-time window and the instantaneous power of the light signal at the end of the corresponding period of the short-time window are taken as the energy dissipation ratio in the short-time window; Obtaining the length of the zero-crossing period, calculating the ratio of the energy dissipation ratio of the previous short-time window to the length of the zero-crossing period as the first signal-to-noise ratio judgment value; Obtaining the energy sum of all signal components in the current short-time window; calculating the ratio of the energy sum within the frequency range of interest in the current short-time window to the energy sum of all signal components as the second signal-to-noise ratio judgment value; The absolute value of the difference between the first signal-to-noise ratio judgment value and the second signal-to-noise ratio judgment value is used as the signal-to-noise ratio of the current short-time window.

[0007] Preferably, the step of selecting the calibration window from different short-time windows of the optical signal according to the signal-to-noise ratio comprises: For short-time windows containing continuous mutations, the difference in signal-to-noise ratios within adjacent mutation windows is calculated, and the latter of the two short-time windows with the largest difference in signal-to-noise ratio is used as the calibration window.

[0008] Preferably, the method for obtaining the membership of the minimum instantaneous power position to the arc stability segment is: Obtain the minimum instantaneous power position in the calibration window; the signal segments on the left and right sides of the minimum instantaneous power position in the calibration window are respectively recorded as reference signal segment A and reference signal segment B; Obtaining the integral values ​​of the A reference signal segment and the B reference signal segment; Calculate the ratio of the integral values ​​of the reference signal segment A and the reference signal segment B as the first degree of membership; Calculate the ratio of the time length between the centroid position and the left and right side boundaries in the previous adjacent short-time window of the calibration window as the second membership degree; The difference between the first membership degree and the second membership degree is negatively correlated and mapped to obtain the membership degree of the minimum instantaneous power position to the arc stable segment.

[0009] Preferably, the method for obtaining the degree of membership of the minimum instantaneous power position to the arc ignition end is: Calculate the ratio of the integral values ​​of the B reference signal segment and the A reference signal segment as the third membership degree; Calculate the ratio of the time length between the centroid position and the left and right side boundaries in the next adjacent short-time window of the calibration window as the fourth degree of membership; The difference between the third membership degree and the fourth membership degree is negatively correlated and mapped to obtain the membership degree of the minimum instantaneous power position to the arc ignition end.

[0010] Preferably, comparing the common frequencies and the newly added frequencies on the left and right sides of the minimum instantaneous power position to determine the reset point estimation error of the phase reset point where the minimum instantaneous power position is determined includes: Obtain the number of common frequency types in the phase spectra of the A reference signal segment and the B reference signal segment, and obtain the number of frequency types newly added to the B reference signal segment compared to the A reference signal segment; Calculate the correlation between the two phase spectra of the A reference signal segment and the B reference signal segment; The difference between the number of common frequency types and the number of newly added frequency types is used as the numerator, the correlation between the phase spectra of reference signal segment A and reference signal segment B is used as the denominator, and the ratio of the numerator and the denominator is used as the reset point estimation error.

[0011] Preferably, estimating the error according to the subordinate direction and the reset point, determining the arc ignition position within the calibration window, and obtaining the delay value includes: Correct the minimum instantaneous power moment in the calibration window to its belonging direction, and calculate the energy integral value after translation every time it is translated one position in the belonging direction; Obtaining the energy integral value of the first short-time window in the continuous mutation optical signal segment to which the calibration window belongs; The minimum instantaneous power moment is continuously translated along its belonging direction until the ratio of the translated energy integral value to the energy integral value of the first short-time window is the reset point closest to the reset point. When estimating the error, the position where the minimum instantaneous power moment is located is taken as the target position; When the subordinate direction is the arc stable end, the target position is the arc peak position in the marking window; the distance between the arc peak position and the midpoint position of the marking window is used as the time delay value between the zero-crossing period of the AC circuit and the arc signal ignition-extinguishing period in this section of the continuous mutation signal; When the subordinate direction is the arc ignition end, the target position is the arc ignition position in the marking window; the distance between the arc ignition position and the zero-crossing moment on the left side of the marking window is used as the delay value between the zero-crossing period of the AC circuit and the arc signal ignition-extinguishing period in this section of the continuous mutation signal.

[0012] Preferably, dividing the arc ignition-extinguishing cycle according to the time delay value includes: The time delay value is the distance from the start time of the calibration window to the start time of the arc ignition-extinguishing cycle, and the start time of the arc ignition-extinguishing cycle is obtained based on the time delay value.

[0013] Preferably, the method for dividing different short-time windows corresponding to the optical signal is: The light signal of the arc light collected when the arc occurs is subjected to short-time Fourier transform to obtain the cycle length, and the light signal of the arc light is divided based on the cycle length to obtain multiple short-time windows corresponding to the light signal.

[0014] In a second aspect, an arc transmission detection system with a self-checking function is provided, the system comprising the following modules: A data acquisition module, used to acquire the light signal of the arc light, and analyze and obtain the frequencies of interest in different short-time windows corresponding to the light signal, wherein the frequencies of interest are periodic frequency components; The first determination module is used to analyze the energy dissipation multiple of the historical short-time window and determine the signal-to-noise ratio in combination with the frequency of interest of the current short-time window; The second determination module is used to select a calibration window from different short-time windows of the optical signal according to the signal-to-noise ratio; determine the membership of the minimum instantaneous power position to the arc stabilization section and to the arc ignition end respectively according to the relative relationship between the minimum instantaneous power position in the calibration window and the centroid of the adjacent short-time window, and determine the membership direction based on the membership; The arc cycle division module is used to compare the common frequencies and newly added frequencies on the left and right sides of the minimum instantaneous power position, determine the reset point estimation error of the minimum instantaneous power position as the phase reset point; determine the arc ignition position in the calibration window according to the subordinate direction and the reset point estimation error, and obtain the delay value; divide the arc ignition-extinguishing cycle according to the delay value.

[0015] In a third aspect, an embodiment of the present invention provides an electronic device, including a memory and a processor, wherein the memory stores executable code, and when the processor executes the executable code, various possible embodiments of the first aspect are implemented.

[0016] In a fourth aspect, an embodiment of the present invention provides a computer program product, which includes: a computer program code, which, when executed on a computer, enables the computer to execute the method in the first aspect or any possible implementation of the first aspect.

[0017] In a fifth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, enables the computer to execute various possible implementations of the first aspect.

[0018] The embodiments of the present invention have at least the following beneficial effects: When the noise and the optical signal are overlapped, and the real optical signal period and waveform cannot be obtained, the conventional signal-to-noise ratio calculation method cannot be applied. Therefore, the present invention uses the energy dissipation multiple of the frequency component of interest corresponding to the optical signal to calculate the signal-to-noise ratio of the current short-time window. When the difference in the signal-to-noise ratio of adjacent short-time windows is greater, it reflects that a sudden increase in noise may have occurred between the two short-time windows, that is, the arc is extinguished and re-ignited in the short-time window. Instability occurs, so according to this characteristic, the calibration window is screened out from different short-time windows of the optical signal. The subsequent delay analysis is performed based on the calibration window. According to the relative relationship between the minimum instantaneous power position in the calibration window and the centroid of the adjacent short-time window, the membership of the minimum instantaneous power position to the arc stable segment and to the arc ignition end is determined respectively, and the membership direction is determined based on the membership. The determination of the membership direction is to obtain the estimated direction of the delay generation position. For different membership directions, the calculation method of the delay value is different. When the arc is at the node where two ignition-extinguishing cycles alternate, some characteristics of the arc will be reset and reestablished when waiting for the next ignition. The arc characteristic reset will cause a phase reset, so the reset point estimation error is determined by analysis. Finally, the arc ignition position in the calibration window is determined by combining the subordinate direction and the reset point estimation error, and the delay value is obtained; the arc ignition-extinguishing cycle is divided according to the delay value. The delay phenomenon occurs from the calibration window, which affects all subsequent short-term windows. By determining the delay value, the problem of the non-synchronicity of the zero-crossing cycle and the arc ignition-extinguishing cycle of the AC circuit is solved, and the real arc ignition-extinguishing cycle is determined, which can retain the characteristic information of the arc signal to the greatest extent and improve the transmission quality and information validity of the arc signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A method flow chart of an arc transmission detection method with a self-checking function provided by one embodiment of the present invention; Figure 2 A schematic diagram of an optical signal originally collected by an arc probe provided by an embodiment of the present invention; Figure 3 A schematic diagram of an arc ignition-extinguishing cycle and a zero-crossing cycle provided by an embodiment of the present invention; Figure 4 A schematic diagram of the structure of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the following, in combination with the accompanying drawings and preferred embodiments, an arc transmission detection method with a self-checking function proposed by the present invention, its specific implementation method, structure, characteristics and effects are described in detail as follows.

[0022] In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0023] Among them, in the description of the embodiments of the present invention, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a way to describe the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present invention, "multiple" refers to two or more than two.

[0024] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0025] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0026] The embodiments of the present invention are described below in conjunction with the accompanying drawings. Those skilled in the art will appreciate that, with the development of technology and the emergence of new scenarios, the technical solutions provided by the embodiments of the present invention are also applicable to similar technical problems.

[0027] The specific scheme of the arc transmission detection method with self-checking function provided by the present invention is described in detail below with reference to the accompanying drawings.

[0028] See also Figure 1 , which shows a flow chart of the steps of an arc transmission detection method with a self-checking function provided by an embodiment of the present invention, the method comprising the following steps: Step S100, acquiring an arc light signal, and analyzing to obtain frequencies of interest in different short-time windows corresponding to the light signal, wherein the frequencies of interest are periodic frequency components.

[0029] An electric arc is a very strong electrical discharge phenomenon. It ionizes the gas through electric current and forms a conductive channel, thereby generating a high temperature and high brightness phenomenon. It usually occurs between two conductors that are disconnected or in contact, especially at the electrical contacts in switchgear, circuit breakers or other power systems. The power of the short-circuit arc in the switch cabinet can be as high as 100MW. The energy generated by the arc burning increases exponentially with the arc burning time and the change in the short-circuit current. The high temperature and high pressure generated by the burning will gradually destroy components, copper bars and switch cabinets in rows. The bright arc light and toxic gases also cause great harm to the human body.

[0030] The embodiment of the present invention is an arc transmission detection method with a self-checking function based on an arc protection monitoring device. The arc protection monitoring device is a product designed based on a system current signal and a signal provided by an arc sensing sensor, and is mainly composed of a microprocessor module, a key display module, a signal input module, a signal output module and a power supply module. The arc transmission detection method with a self-checking function is an analysis and processing implemented by the microprocessor module.

[0031] Arc sensors are installed in various compartments in the cabinet to achieve simple to complex, selective protection. Arc sensors are also called arc probes. Arc probes are light sensing elements that detect the sudden increase in light intensity when an arc fault occurs.

[0032] In the embodiment of the present invention, high-precision sensors are used to capture the changes in light, heat and other physical parameters generated by the arc, and convert this information into transmittable signals to achieve real-time monitoring of the arc state. This conversion process is arc signal transmission, which is performed at the arc probe. Figure 2 , Figure 2Schematic diagram of the original optical signal collected by the arc probe.

[0033] High-voltage switchgear is generally an AC circuit. The AC power supply provides periodically changing voltage and current. The arc will periodically extinguish and reignite as the current changes. In an AC circuit, the arc may continue to exist for a very short period of time when the voltage passes through zero due to the influence of arc thermal inertia, electromagnetic fields, charged particles, etc., which may affect the formation of subsequent arcs and cause delay problems.

[0034] The arc ignition-extinguishing cycle generally occurs during the zero-crossing cycle, and it extinguishes and reignites periodically as the current changes. However, due to the deformation of the arc and the change of the air medium, a time delay occurs. Figure 3 , Figure 3 Schematic diagram of arc ignition-extinguishing cycle and zero-crossing cycle.

[0035] When an arc occurs, the strong radiation generated will be captured by the optical sensor of the probe to generate an analog signal; the analog signal is transmitted to the low-pass filter through the optical fiber for preliminary preprocessing. The low-pass filter can be set to a smaller cutoff frequency, which can be set to 50kHz in the embodiment of the present invention to avoid destroying the effective information in the signal.

[0036] The processed optical signal is then converted into a digital signal to obtain an optical signal with a sampling rate of 100kHz and input into the microprocessor. The microprocessor detects the power supply voltage input signal through the conditioning circuit and determines the start and end time of each cycle according to the voltage signal, that is, the zero crossing point of the AC voltage signal, and the phase is 0° or 180°.

[0037] Perform short-time Fourier transform on the light signal of the arc light collected when the arc occurs to obtain the cycle length, set the cycle length as the short-time window length, and divide the light signal of the arc light based on the short-time window length, so that the light signal corresponds to multiple short-time windows.

[0038] After performing short-time Fourier transform on the optical signal, the amplitude spectrum and phase spectrum in all short-time windows are determined.

[0039] After determining the short-time window, the energy in the continuous short-time windows is differentially calculated to identify the short-time windows with energy surges. In the embodiment of the present invention, when the difference between the energies in adjacent short-time windows is greater than a preset energy difference, it is determined that an energy surge occurs in the adjacent short-time windows, and the next short-time window in the adjacent short-time windows is used as a mutation window. In the embodiment of the present invention, the preset energy difference can be set by the implementer based on an empirical value, and in the embodiment of the present invention, the preset energy difference can be set to 30.

[0040] When the energy surge occurs in only one short-term window, it is a transient mutation; when the energy surge occurs or persists in multiple short-term windows, it is a continuous mutation. That is, when the number of consecutive mutation windows is greater than 2, the two mutation windows are divided into short-term windows of continuous mutation.

[0041] For all short-term windows of continuous mutation, the optical signal intensity is sampled at the end of each cycle, and the instantaneous power is calculated and saved.

[0042] When an arc occurs, the circuit is in an open circuit state, and when an arc occurs, it is in a short-term connected state. Therefore, a large amount of noise will be briefly introduced into the optical signal. Each time the arc flashes and extinguishes, high-frequency noise will be introduced. These noises usually appear as pulsed interference.

[0043] For the short-time window of continuous mutation, the same frequency components in the amplitude spectrum of every two adjacent short-time windows are obtained; Taking any two adjacent short-time windows in the short-time window of continuous mutation as the target adjacent short-time windows, after deleting the same frequency components in any one or more amplitude spectra in the target adjacent short-time windows, the average value of the cross-correlation function of the amplitude spectrum of each short-time window in the previous short-time window and the next short-time window in the target adjacent short-time window is calculated; the average value of the cross-correlation function is normalized to obtain the periodic characteristics of the target adjacent short-time windows; The same frequency components in the target adjacent short-time window are continuously deleted and retained until the periodic characteristic of the target adjacent short-time window reaches the maximum, and the retained frequency components that are not deleted are used as the frequencies of interest of the next short-time window in the target adjacent short-time window.

[0044] The frequency of interest is the most periodic frequency component in each short-time window, which can be regarded as the arc light signal component that may exist in the continuous mutation signal segment. It should be noted that each short-time window has its own corresponding frequency of interest.

[0045] In some embodiments, after deleting some of the same frequency components and obtaining the average value of the cross-correlation function, the average value of the cross-correlation function is normalized. The square mean of the amplitude spectrum in the short-time window can be used to normalize it to obtain the periodic characteristic ; Where M is the periodic characteristic; is the average value of the cross-correlation function; is the square mean of the amplitude spectrum in the short-time window.

[0046] Step S200, analyzing the energy dissipation ratio of the historical short-time window and combining it with the frequency of interest of the current short-time window to determine the signal-to-noise ratio.

[0047] First, for different short-time windows corresponding to each optical signal, the total energy in each frequency range of interest is calculated using the definite integral method.

[0048] Assuming that the arc has an ideal stable cycle of ignition and extinguishing, the total energy in the frequency range of interest is calculated. The total arc light signal energy in the short-time window and the instantaneous power of the light signal at the end of the corresponding cycle of the short-time window are taken as the energy dissipation rate in the short-time window.

[0049] Power is the rate of change of energy over time, that is, power equals energy divided by time. In a time period, the total energy of the arc light signal divided by the ratio of the instantaneous power at the end of the period represents the time required for the arc energy to dissipate. In the next period, it takes the same amount of time to reignite the arc and maintain the arc with the same energy intensity.

[0050] After the energy dissipation factor is determined, the signal-to-noise ratio is determined by combining the energy dissipation factor of the historical short-time window with the frequency of interest of the current short-time window.

[0051] The length of the zero-crossing period is obtained, and the ratio of the energy dissipation ratio of the previous short-time window to the length of the zero-crossing period is calculated as the first signal-to-noise ratio judgment value.

[0052] The energy sum of all signal components in the current short-time window is obtained; and the ratio of the energy sum within the frequency range of interest in the current short-time window to the energy sum of all signal components is calculated as the second signal-to-noise ratio judgment value.

[0053] The absolute value of the difference between the first signal-to-noise ratio judgment value and the second signal-to-noise ratio judgment value is used as the signal-to-noise ratio of the current short-time window.

[0054] In some embodiments, the i-th short-time window is used as the current short-time window, and the signal-to-noise ratio of the current short-time window is The calculation formula is: ;in, is the energy dissipation rate of the i-1th short-time window; T is the length of the zero-crossing period; is the sum of the energy in the frequency range of interest in the i-th short-time window; is the sum of the energy of all signal components in the i-th short-time window; is the first signal-to-noise ratio judgment value of the i-th short-time window; is the second signal-to-noise ratio judgment value of the i-th short-time window.

[0055] When the arc has an ideal stable ignition-extinguishing cycle, The ratio should be The reason why they are not equal is due to arc instability and noise. The difference is the noise change of the i-th short-time window compared with the previous short-time window. The arc instability is essentially noise. The signal-to-noise ratio of the short-time window is That is, the signal-to-noise ratio.

[0056] When noise and optical signals are mixed and the real optical signal period and waveform cannot be obtained, the conventional signal-to-noise ratio calculation method cannot be applied. In this case, the problem can be solved by obtaining the frequency component of interest in the current step, calculating the energy dissipation ratio of the frequency component of interest in the previous short-time window, estimating the noise change in the next zero-crossing period, and then calculating the signal-to-noise ratio.

[0057] Step S300, based on the signal-to-noise ratio, a calibration window is selected from different short-time windows of the optical signal; based on the relative relationship between the minimum instantaneous power position in the calibration window and the centroid of the adjacent short-time window, the membership of the minimum instantaneous power position to the arc stabilization segment and to the arc ignition end is determined respectively, and the membership direction is determined based on the membership.

[0058] For a continuous mutation optical signal segment containing a short-time window of continuous mutation, the difference in signal-to-noise ratio within adjacent mutation windows is calculated. When the difference in signal-to-noise ratio is the largest, it reflects that a sudden increase in noise may have occurred between the two short-time windows, that is, instability occurs when the arc is extinguished and reignited within the short-time window. The latter short-time window of the two short-time windows with the largest difference in signal-to-noise ratio is called the calibration window.

[0059] An unstable arc state is generated during the zero-crossing period. The corresponding short-time window is the position where the time delay between the zero-crossing period of the AC circuit and the ignition-extinguishing period of the arc light signal begins to occur. It is very likely that the synchronization between the two will be destroyed from this moment on.

[0060] Therefore, further, according to the relative relationship between the minimum instantaneous power position in the calibration window and the centroid position of the adjacent cycles, the membership of the minimum instantaneous power position to the arc stable segment and the membership of the minimum instantaneous power position to the arc ignition end are determined respectively.

[0061] First, calculate the direction of the minimum instantaneous power: The three-cycle method is used to obtain the centroid position of the two adjacent short-time windows with the calibration window as the center. In one embodiment of the present invention, the centroid position of the short-time window can be the center of the signal segment. In another embodiment of the present invention, the centroid position of the short-time window can also be the average time position.

[0062] When the previous adjacent short-time window of the calibration window has no delay, the centroid should be biased to the center; when the next adjacent short-time window of the calibration window has a delay, the centroid may be biased to the left or right.

[0063] The position within the calibration window is where the delay is occurring and a complete arc may not be generated, so the centroid cannot represent the position where the arc occurs.

[0064] The minimum instantaneous power position of the calibration window is used to replace the arc occurrence position in the calibration window to obtain the minimum instantaneous power position in the calibration window, and the signal segments on the left and right sides of the minimum instantaneous power position in the calibration window are respectively recorded as reference signal segment A and reference signal segment B.

[0065] Get the integral values ​​of reference signal segment A and reference signal segment B, which are recorded as , The integral value is the integral value of the energy in the reference signal segment, that is, the sum of the energy in the reference signal segment.

[0066] Then, the membership of the minimum instantaneous power position to the previous adjacent short-time window and the next adjacent short-time window is obtained respectively: The minimum instantaneous power position for the previous adjacent short-time window, that is, the method for obtaining the membership of the minimum instantaneous power position for the arc stable segment is: Calculate the ratio of the integral values ​​of the reference signal segment A and the reference signal segment B as the first degree of membership; Calculate the ratio of the time length between the centroid position and the left and right side boundaries in the previous adjacent short-time window of the calibration window as the second membership degree; The difference between the first membership degree and the second membership degree is negatively correlated and mapped to obtain the membership degree of the minimum instantaneous power position to the arc stable segment.

[0067] If the arc in the previous adjacent window is stable and has no delay, then these two time lengths represent the time lengths of the arc rising segment and the arc dissipation segment respectively.

[0068] The difference between the first membership and the second membership represents the difference between the integral ratio of the reference signal segment A and the reference signal segment B, and the ratio of the time length of the arc rise segment and the dissipation segment. The smaller the difference is, the closer the minimum instantaneous power position in the marking window is to the centroid position of the previous window without delay. That is, the minimum instantaneous power position in the marking window is more likely to be the arc stable segment, so the probability that the minimum instantaneous power position in the marking window belongs to the arc stable segment is greater.

[0069] In some embodiments, the membership of the minimum instantaneous power position to the arc stability segment is The calculation formula is: ;in, The time length from the centroid position to the left boundary in the i-1th short-time window; It is the time length from the centroid position to the right boundary in the i-1th short-time window.

[0070] The method for obtaining the minimum instantaneous power position for the next adjacent short-time window, that is, the minimum instantaneous power position for the arc ignition end, is: The ratio of the integral values ​​of the B reference signal segment and the A reference signal segment is calculated as the third membership degree.

[0071] The ratio of the time length between the centroid position and the left and right side boundaries in the next adjacent short-time window of the calibration window is calculated as the fourth membership degree.

[0072] The difference between the third membership degree and the fourth membership degree is negatively correlated and mapped to obtain the membership degree of the minimum instantaneous power position to the arc ignition end.

[0073] If the arc in the next adjacent short-time window has been affected by the time delay, the arc energy dissipation process in the marking window may be delayed to the next adjacent short-time window, and the ignition-extinguishing process of the next adjacent window will continue to be delayed. Then, in the i+1th short-time window, the time length ratio of the arc rising segment and the arc dissipation segment may be reversed.

[0074] The difference between the third membership and the fourth membership represents the integral ratio of the B reference signal segment and the A reference signal segment, and the difference in the time length ratio of the arc rise segment and the arc dissipation segment. The smaller the difference, the more consistent the time delay relationship in the marking window is with the next adjacent short-time window. Therefore, the position of the minimum instantaneous power in the calibration window is more likely to be the ignition end of the arc.

[0075] In some embodiments, the membership of the minimum instantaneous power position to the arc stability segment is The calculation formula is: ;in, The time length from the centroid position to the left boundary in the i+1th short-time window; It is the time length from the centroid position to the right boundary in the i+1th short-time window.

[0076] After the membership degrees of the minimum instantaneous power position to the arc stabilization section and to the arc ignition end are determined respectively, the membership direction is determined based on the membership degrees.

[0077] The two memberships correspond to the left and right sides of the calibration window respectively. The two memberships of the minimum instantaneous power position for the arc stable section and the arc ignition end are compared, and the side with a higher membership is taken as the membership direction of the minimum instantaneous power position.

[0078] The purpose of calculating the subordinate direction of the minimum instantaneous power position is to obtain the estimated direction of the delay generation position. When the subordinate direction is biased toward adjacent windows in different directions, the calculation method of the delay value is different.

[0079] Step S400, compare the common frequencies and newly added frequencies on the left and right sides of the minimum instantaneous power position, determine the reset point estimation error of the minimum instantaneous power position as the phase reset point; determine the arc ignition position in the calibration window according to the subordinate direction and the reset point estimation error, and obtain the delay value; divide the arc ignition-extinguishing cycle according to the delay value.

[0080] When the arc is at the node where two ignition-extinguishing cycles alternate, certain characteristics of the arc will be reset, waiting to be reestablished when the next ignition occurs. The arc characteristic reset will cause a phase reset.

[0081] First, the phase spectra of the A reference signal segment and the B reference signal segment are obtained respectively.

[0082] Phase reset usually means that the phase of the signal changes suddenly at a certain moment, which is manifested in the phase spectrum as a jump in the phase value at the corresponding frequency, that is, the phase value suddenly jumps from one value to another.

[0083] Obtain the common frequency types in the phase spectra of reference signal segment A and reference signal segment B, and obtain the number of common frequency types, which is recorded as P; obtain the frequency types newly added to reference signal segment B compared to reference signal segment A, and obtain the number of newly added frequency types, which is recorded as Z.

[0084] Calculate the correlation between the two phase spectra of reference signal segment A and reference signal segment B, denoted as ; The difference between the number of common frequency types and the number of newly added frequency types is used as the numerator, the correlation between the phase spectra of reference signal segment A and reference signal segment B is used as the denominator, and the ratio of the numerator and the denominator is used as the reset point estimation error.

[0085] In some embodiments, the calculation formula of the reset point estimation error K is: ; The larger the PZ, the smaller the denominator. The smaller it is, the closer the minimum instantaneous power position is to the phase reset point of reference signal segment A and reference signal segment B; therefore, the K value is called the reset point estimation error of the reset point.

[0086] Furthermore, the delay between the zero-crossing period of the AC circuit and the arc light ignition-extinguishing period is calculated: The minimum instantaneous power moment in the calibration window is corrected toward its belonging direction. Every time it is translated one position toward the belonging direction, the integral value after translation is calculated. The integral value is the energy integral value, so it can be directly called the energy integral value after translation in the following text; the energy integral value after translation is also the energy integral value between the minimum instantaneous power moment after translation and the boundary of the belonging direction; for example, when the belonging direction is the arc stable end, the energy integral value after translation is also the energy integral value between the minimum instantaneous power moment after translation and the left boundary of the calibration window; when the belonging direction is the arc ignition end, the energy integral value after translation is also the energy integral value between the minimum instantaneous power moment after translation and the right boundary of the calibration window.

[0087] Obtaining the energy integral value of the first short-time window in the continuous mutation optical signal segment to which the calibration window belongs; The minimum instantaneous power moment is continuously translated along its belonging direction until the ratio v of the translated energy integral value to the energy integral value of the first short-time window is closest to the reset point estimation error, and the position of the minimum instantaneous power moment is taken as the target position; wherein, when the ratio v is closest to the reset point estimation error, it can also be understood as when the difference between the ratio v and the reset point estimation error is the smallest.

[0088] When the subordinate direction is the arc stable end, the target position is the arc peak position in the marking window; wherein, the subordinate direction is the arc stable end, which can also be understood as the subordinate direction is the direction from the calibration window to the previous short-time window.

[0089] The distance between the arc peak position and the midpoint position of the marking window is taken as the time delay value between the zero-crossing period of the AC circuit and the ignition-extinguishing period of the arc signal in the continuous mutation signal.

[0090] When the subordinate direction is the arc ignition end, the target position is the arc ignition position in the marking window; wherein, the subordinate direction is the arc ignition end, which can also be understood as the subordinate direction being the direction from the calibration window to the next short-time window.

[0091] The distance between the arc ignition position and the zero-crossing moment on the left side of the mark window is used as the time delay value between the zero-crossing period of the AC circuit and the arc signal ignition-extinguishing period in the continuous mutation signal. It should be noted that the length of the zero-crossing period of the AC circuit is the same as the length of the short-time window in the embodiment of the present invention.

[0092] The time delay phenomenon occurs from the calibration window, which affects all subsequent short-time windows. Therefore, the arc ignition-extinguishing cycle of each continuous mutation optical signal segment can be determined according to the AC cycle and the time delay value; and then the arc ignition-extinguishing cycle in each short-time window in each continuous mutation signal segment can be divided out.

[0093] The arc ignition-extinguishing cycle is divided according to the delay value. Specifically, the delay value is the distance from the start time of the calibration window to the start time of the arc ignition-extinguishing cycle, and the start time of the arc ignition-extinguishing cycle is obtained based on the delay value. It should be noted that the calibration window of each continuous mutation optical signal segment is different, and its corresponding delay window is different, so the start time of the arc ignition-extinguishing cycle of the short-time window in different continuous mutation optical signal segments is also different. The purpose of the embodiment of the present invention is to retain each complete arc ignition-extinguishing cycle, and the complete arc ignition-extinguishing cycle is retained between the start times of two adjacent arc ignition-extinguishing cycles, so the time period between the start times of two adjacent arc ignition-extinguishing cycles can be directly used as an arc ignition-extinguishing cycle, and the range is slightly larger, but because smoothing can be performed later, certain losses can be avoided.

[0094] In order to preserve the arc characteristics, Gaussian filtering is used to smooth the signal in each arc ignition-extinguishing cycle to eliminate the noise in the continuous mutation signal segment, and the processed signal is transmitted to the amplifier circuit for amplification.

[0095] The amplified signal is input into the integration circuit. Every time a signal of an arc ignition-extinguishing cycle is input, the microprocessor outputs a control signal to set the output of the integration circuit to zero, ensuring that each arc ignition-extinguishing cycle is processed separately. Finally, the transmission process of the optical signal is completed to obtain the processed optical signal.

[0096] As a preferred embodiment of the present invention, the arc protection monitoring device may also include a self-checking module for programming and arc identification. Please refer to Table 1, which shows the existing arc characteristics: Table 1 The arc signal after noise elimination retains the effective information in each arc ignition-extinguishing cycle and has high clarity.

[0097] As a preferred embodiment of the present invention, the processed arc ignition-extinguishing cycle can be detected and identified using an existing arc recognition model or a pre-programmed detection module. After the arc fault occurs and causes the device to trip, the main control unit or the feeder protection unit can accurately record the location information of the arc fault detected by the arc probe, and can record in detail the fault phase current value at the time of action.

[0098] An embodiment of the present invention provides an arc transmission detection system with a self-checking function, the system comprising: A data acquisition module, used to acquire the light signal of the arc light, and analyze and obtain the frequencies of interest in different short-time windows corresponding to the light signal, wherein the frequencies of interest are periodic frequency components; The first determination module is used to analyze the energy dissipation multiple of the historical short-time window and determine the signal-to-noise ratio in combination with the frequency of interest of the current short-time window; The second determination module is used to select a calibration window from different short-time windows of the optical signal according to the signal-to-noise ratio; determine the membership of the minimum instantaneous power position to the arc stabilization section and to the arc ignition end respectively according to the relative relationship between the minimum instantaneous power position in the calibration window and the centroid of the adjacent short-time window, and determine the membership direction based on the membership; The arc cycle division module is used to compare the common frequencies and newly added frequencies on the left and right sides of the minimum instantaneous power position, determine the reset point estimation error of the minimum instantaneous power position as the phase reset point; determine the arc ignition position in the calibration window according to the subordinate direction and the reset point estimation error, and obtain the delay value; divide the arc ignition-extinguishing cycle according to the delay value.

[0099] Optionally, the transmission medium may be a wired link, such as but not limited to coaxial cable, optical fiber, and digital subscriber line, or a wireless link, such as but not limited to Wireless Fidelity (WIFI), Bluetooth, and mobile device network.

[0100] It should be noted that the device provided in the above embodiment is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the computer device can be divided into different functional modules to complete all or part of the functions described above.

[0101] Figure 4 is a schematic diagram of the structure of a computer device provided by an embodiment of the present invention. Figure 4 As shown, the computer device 500 includes: a memory 510, a processor 520, and a computer program 530 stored in the memory 510 and running on the processor 520, wherein when the processor 520 executes the computer program 530, the computer device can execute any one of the arc transmission detection methods with self-checking function introduced above.

[0102] In addition, an embodiment of the present invention also protects a device, which may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to execute an arc transmission detection method with a self-checking function provided by an embodiment of the present invention.

[0103] The embodiment of the present invention can divide the functional modules of the device according to the above method example. For example, each functional module can be corresponded, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0104] In the case of dividing each module according to each function, the device may also include a signal uploading module, a determining module, an adjusting module, etc. It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here.

[0105] It should be understood that the device provided in the embodiment of the present invention is used to execute the above-mentioned arc transmission detection method with self-checking function, and thus can achieve the same effect as the above-mentioned implementation method.

[0106] In the case of an integrated unit, the device may include a processing module and a storage module. When the device is applied to a device, the processing module may be used to control and manage the actions of the device. The storage module may be used to support the device to execute mutual program codes, etc. The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. The processor may also be a combination that implements a computing function, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

[0107] In addition, the device provided in an embodiment of the present invention may specifically be a chip, a component or a module, and the chip may include a connected processor and a memory; wherein the memory is used to store instructions, and when the processor calls and executes the instructions, the chip can execute an arc transmission detection method with a self-checking function provided in the above embodiment.

[0108] An embodiment of the present invention also provides a computer-readable storage medium, which stores computer program code. When the computer program code runs on a computer, the computer executes the above-mentioned related method steps to implement an arc transmission detection method with a self-checking function provided in the above embodiment.

[0109] An embodiment of the present invention further provides a computer program product. When the computer program product is run on a computer, the computer executes the above-mentioned related steps to implement an arc transmission detection method with a self-checking function provided in the above embodiment.

[0110] Among them, the device, computer-readable storage medium, computer program product or chip provided in the embodiments of the present invention are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above, and will not be repeated here. Through the description of the above implementation methods, technicians in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In the embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways.

[0111] The device embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division. There may be other divisions in actual implementation. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection of devices or units, which may be electrical, mechanical or other forms.

[0112] It should also be noted that, in this article, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0113] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0114] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0115] The above contents are only specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered within the protection scope of the present invention.

Claims

1. An arc transmission detection method with self-checking function, characterized in that: The method comprises the following steps: Acquire the light signal of the arc light, and analyze and obtain the frequencies of interest in different short-time windows corresponding to the light signal, wherein the frequencies of interest are periodic frequency components; Analyze the energy dissipation ratio of the historical short-time window and determine the signal-to-noise ratio by combining it with the frequency of interest in the current short-time window; According to the signal-to-noise ratio, a calibration window is selected from different short-time windows of the optical signal; according to the relative relationship between the minimum instantaneous power position in the calibration window and the centroid of the adjacent short-time window, the membership of the minimum instantaneous power position to the arc stable section and to the arc ignition end is determined respectively, and the membership direction is determined based on the membership; Compare the common frequencies and newly added frequencies on the left and right sides of the minimum instantaneous power position to determine the reset point estimation error of the phase reset point with the minimum instantaneous power position as the phase reset point; determine the arc ignition position within the calibration window based on the subordinate direction and the reset point estimation error, and obtain the time delay value; divide the arc ignition-extinguishing cycle based on the time delay value.

2. The arc transmission detection method with self-checking function according to claim 1 is characterized in that: The method for acquiring the frequencies of interest in different short-time windows corresponding to the optical signal is as follows: Obtain short-time windows of persistent mutations in different short-time windows corresponding to the signal; Taking any two adjacent short-time windows in the short-time window of continuous mutation as the target adjacent short-time windows, after deleting the same frequency components in any one or more amplitude spectra in the target adjacent short-time windows, the average value of the cross-correlation function of the amplitude spectrum of each short-time window in the previous short-time window and the next short-time window in the target adjacent short-time window is calculated; the average value of the cross-correlation function is normalized to obtain the periodic characteristics of the target adjacent short-time windows; The same frequency components in the target adjacent short-time window are continuously deleted and retained until the periodic characteristic of the target adjacent short-time window reaches the maximum, and the retained frequency components that are not deleted are used as the frequencies of interest of the next short-time window in the target adjacent short-time window.

3. The arc transmission detection method with self-checking function according to claim 1 is characterized in that: The analyzing the energy dissipation multiple of the historical short-time window and combining the frequency of interest of the current short-time window to determine the signal-to-noise ratio includes: The total arc light signal energy in the short-time window and the instantaneous power of the light signal at the end of the corresponding period of the short-time window are taken as the energy dissipation ratio in the short-time window; Obtaining the length of the zero-crossing period, calculating the ratio of the energy dissipation ratio of the previous short-time window to the length of the zero-crossing period as the first signal-to-noise ratio judgment value; Obtaining the energy sum of all signal components in the current short-time window; calculating the ratio of the energy sum within the frequency range of interest in the current short-time window to the energy sum of all signal components as the second signal-to-noise ratio judgment value; The absolute value of the difference between the first signal-to-noise ratio judgment value and the second signal-to-noise ratio judgment value is used as the signal-to-noise ratio of the current short-time window.

4. The arc transmission detection method with self-checking function according to claim 1 is characterized in that: The step of selecting a calibration window from different short-time windows of the optical signal according to the signal-to-noise ratio comprises: For short-time windows containing continuous mutations, the difference in signal-to-noise ratios within adjacent mutation windows is calculated, and the latter of the two short-time windows with the largest difference in signal-to-noise ratio is used as the calibration window.

5. The arc transmission detection method with self-checking function according to claim 1 is characterized in that: The method for obtaining the membership degree of the minimum instantaneous power position to the arc stability segment is: Obtain the minimum instantaneous power position in the calibration window; the signal segments on the left and right sides of the minimum instantaneous power position in the calibration window are respectively recorded as reference signal segment A and reference signal segment B; Obtaining the integral values ​​of the A reference signal segment and the B reference signal segment; Calculate the ratio of the integral values ​​of the reference signal segment A and the reference signal segment B as the first degree of membership; Calculate the ratio of the time length between the centroid position and the left and right side boundaries in the previous adjacent short-time window of the calibration window as the second membership degree; The difference between the first membership degree and the second membership degree is negatively correlated and mapped to obtain the membership degree of the minimum instantaneous power position to the arc stable segment.

6. The arc transmission detection method with self-checking function according to claim 5 is characterized in that: The method for obtaining the minimum instantaneous power position's membership to the arc ignition end is: Calculate the ratio of the integral values ​​of the B reference signal segment and the A reference signal segment as the third membership degree; Calculate the ratio of the time length between the centroid position and the left and right side boundaries in the next adjacent short-time window of the calibration window as the fourth degree of membership; The difference between the third membership degree and the fourth membership degree is negatively correlated and mapped to obtain the membership degree of the minimum instantaneous power position to the arc ignition end.

7. The arc transmission detection method with self-checking function according to claim 5 is characterized in that: The comparing the common frequencies and the newly added frequencies on the left and right sides of the minimum instantaneous power position to determine the minimum instantaneous power position as the reset point estimation error of the phase reset point includes: Obtain the number of common frequency types in the phase spectra of the A reference signal segment and the B reference signal segment, and obtain the number of frequency types newly added to the B reference signal segment compared to the A reference signal segment; Calculate the correlation between the two phase spectra of the A reference signal segment and the B reference signal segment; The difference between the number of common frequency types and the number of newly added frequency types is used as the numerator, the correlation between the phase spectra of reference signal segment A and reference signal segment B is used as the denominator, and the ratio of the numerator and the denominator is used as the reset point estimation error.

8. The arc transmission detection method with self-checking function according to claim 1 is characterized in that: The method of estimating the error according to the subordinate direction and the reset point, determining the arc ignition position within the calibration window, and obtaining the time delay value includes: Correct the minimum instantaneous power moment in the calibration window to its belonging direction, and calculate the energy integral value after translation every time it is translated one position in the belonging direction; Obtaining the energy integral value of the first short-time window in the continuous mutation optical signal segment to which the calibration window belongs; The minimum instantaneous power moment is continuously translated along its belonging direction until the ratio of the translated energy integral value to the energy integral value of the first short-time window is the reset point closest to the reset point. When estimating the error, the position where the minimum instantaneous power moment is located is taken as the target position; When the subordinate direction is the arc stable end, the target position is the arc peak position in the marking window; the distance between the arc peak position and the midpoint position of the marking window is used as the time delay value between the zero-crossing period of the AC circuit and the arc signal ignition-extinguishing period in this section of the continuous mutation signal; When the subordinate direction is the arc ignition end, the target position is the arc ignition position in the marking window; the distance between the arc ignition position and the zero-crossing moment on the left side of the marking window is used as the delay value between the zero-crossing period of the AC circuit and the arc signal ignition-extinguishing period in this section of the continuous mutation signal.

9. The arc transmission detection method with self-checking function according to claim 1 is characterized in that: The arc ignition-extinguishing cycle is divided according to the time delay value, including: The time delay value is the distance from the start time of the calibration window to the start time of the arc ignition-extinguishing cycle, and the start time of the arc ignition-extinguishing cycle is obtained based on the time delay value.

10. The arc transmission detection method with self-checking function according to claim 1, characterized in that: The division method of different short-time windows corresponding to the optical signal is: The light signal of the arc light collected when the arc occurs is subjected to short-time Fourier transform to obtain the cycle length, and the light signal of the arc light is divided based on the cycle length to obtain multiple short-time windows corresponding to the light signal.

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