Interference suppression method and system for non-contact electroscope

Abstract

The invention discloses an interference suppression method and system for a non-contact electroscope, and relates to the related technical field of electroscopes, and the method comprises the steps: marking a non-interference detection region of a to-be-detected region in a non-charged environment; collecting environment background electric field signals of the non-interference detection area for multiple times, and generating a zero field signal template for interference suppression; starting a non-contact electroscope in a charged environment to continuously collect real-time operation electric field signals; and performing differential processing on the filtering operation electric field signal based on the zero field signal template, outputting a differential signal, and obtaining a live detection result of the to-be-detected area according to the differential signal. The technical problems that in the prior art, a non-contact electroscope is interfered by a complex electromagnetic environment, detection is prone to misjudgment and missed judgment, interference suppression is difficult to adapt to complex environment changes, and consequently the detection accuracy and reliability are poor are solved, and the purposes of effectively suppressing interference, accurately recognizing electrified signals and improving the detection accuracy and reliability are achieved. And the detection accuracy and reliability of the non-contact electroscope are improved.

Description

Technical Field

[0001] This application relates to the field of electroscope technology, specifically to interference suppression methods and systems for non-contact electroscopes. Background Technology

[0002] Non-contact voltage detectors, by virtue of their ability to perform electrical detection without direct contact with charged bodies, improve the convenience and safety of electrical testing. However, existing non-contact voltage detectors are susceptible to background interference in complex electromagnetic environments. Actual power operation environments are filled with various interferences, such as lightning and static electricity in the natural environment, as well as electromagnetic radiation generated by power equipment during operation, all of which generate electric field signals. These interference signals are mixed with the real charged signals, leading to misjudgments and omissions in the detection results of non-contact voltage detectors, affecting the accuracy and safety of detection. Existing interference suppression methods mostly rely on hardware filtering or fixed threshold judgment, which is difficult to adapt to the complex dynamic changes in the field environment and cannot accurately distinguish between interference signals and real charged signals, resulting in poor interference suppression effects and consequently, poor detection accuracy and reliability of non-contact voltage detectors.

[0003] Therefore, in the current related technologies, there are technical problems such as non-contact electroscopes being susceptible to interference from complex electromagnetic environments, making them prone to misjudgment and missed detection, and interference suppression being difficult to adapt to complex environmental changes, resulting in poor detection accuracy and reliability. Summary of the Invention

[0004] This application provides an interference suppression method and system for non-contact electroscopes, which solves the technical problems in the prior art where non-contact electroscopes are susceptible to interference from complex electromagnetic environments, resulting in easy misjudgment and missed detection, and interference suppression is difficult to adapt to complex environmental changes, leading to poor detection accuracy and reliability. It achieves the technical effect of effectively suppressing interference, accurately identifying charged signals, and improving the detection accuracy and reliability of non-contact electroscopes.

[0005] This application provides an interference suppression method for a non-contact electroscope. The method includes: identifying a non-interference detection area of ​​a region to be detected in a first state, wherein the first state is a non-charged environment; repeatedly acquiring the ambient background electric field signal of the non-interference detection area, storing the repeatedly acquired ambient background electric field signal in an electroscope storage module to generate a zero-field signal template for interference suppression; activating the non-contact electroscope in a second state to continuously acquire the real-time operating electric field signal of the region to be detected, wherein the second state is a charged environment; performing bandpass filtering on the real-time operating electric field signal to obtain a filtered operating electric field signal; performing differential processing on the filtered operating electric field signal based on the zero-field signal template to output a differential signal; and using the differential signal to obtain the charged detection result of the region to be detected.

[0006] In a possible implementation, the interference suppression method for a non-contact electroscope further includes the following steps: a preset sampling interval is used to acquire the environmental background electric field signal of the non-interference detection area N times based on the sampling interval; bandpass filtering is performed on each acquired environmental background electric field signal to obtain N acquired filtered environmental background electric field signals; amplitude and phase data corresponding to the N acquired filtered environmental background electric field signals are extracted to obtain N sets of amplitude and phase data; the average value of the N sets of amplitude and phase data is calculated to output a reference amplitude and a reference phase; a zero-field signal template for interference suppression is generated by combining the reference amplitude and reference phase; and the zero-field signal template is stored in the electroscope storage module.

[0007] In a possible implementation, the interference suppression method for non-contact electroscopes further performs the following processing: acquiring the real-time status of each device in the area to be detected, including running time, running temperature, and running position; when the real-time status of any device in the area to be detected changes, activating the update mechanism to obtain an updated zero-field signal template, performing differential processing on the filtered running electric field signal according to the updated zero-field signal template, and outputting a differential signal.

[0008] In a possible implementation, the interference suppression method for a non-contact electroscope further performs the following processing: In a first state, the area to be detected is initially scanned to obtain an initial electric field signal; the initial electric field signal is subjected to stability verification and consistency verification respectively, and if both verifications pass, it is marked as a non-interference detection area; wherein, the stability verification is to determine whether the electric field amplitude of the initial electric field signal at the same scanning height is lower than a first preset interference tolerance threshold; if the electric field amplitude of the initial electric field signal is lower than the first preset interference tolerance threshold, a stability verification pass result is output; the consistency verification is to determine whether the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than a second preset interference tolerance threshold; if the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than the second preset interference tolerance threshold, a consistency verification pass result is output.

[0009] In a possible implementation, the interference suppression method for a non-contact electroscope further performs the following processing: synchronizing the filtered operating electric field signal with the zero-field signal template based on DPLL technology to obtain a synchronization signal group; performing multi-dimensional differential processing on the two signals of the synchronization signal group, including time-domain differential, frequency-domain differential, and feature-space differential, to obtain a time-domain differential signal, a frequency-domain differential signal, and a feature-space differential signal; and weighted fitting of the time-domain differential signal, the frequency-domain differential signal, and the feature-space differential signal to output a differential signal.

[0010] In a possible implementation, the interference suppression method for a non-contact voltage detector further performs the following processing: obtaining a preset power frequency signal characteristic threshold; performing sliding window detection on the differential signal based on the preset power frequency signal characteristic threshold, extracting an abnormal fluctuation window and an abnormal fluctuation index of the abnormal fluctuation window, wherein the abnormal fluctuation index is obtained by detecting the peak value and skewness of the signal; and combining the abnormal fluctuation index of the abnormal fluctuation window to obtain the live detection result of the area to be detected.

[0011] In a possible implementation, the interference suppression method for the non-contact electroscope further performs the following processing: detecting the historical operating conditions of the equipment in the area to be detected; classifying the operating modes of the equipment in the area to be detected according to the historical operating conditions; outputting multiple operating modes; setting multiple preset power frequency signal feature thresholds corresponding to the multiple operating modes; obtaining matching power frequency signal feature thresholds based on the real-time operating electric field signal of the area to be detected; performing sliding window detection on the differential signal based on the matching power frequency signal feature thresholds; and updating the live detection result.

[0012] This application also provides an interference suppression system for a non-contact electroscope, the system comprising: a non-interference detection area identification module, used to identify the non-interference detection area of ​​the area to be detected in a first state, wherein the first state is a non-charged environment; a zero-field signal template generation module, used to repeatedly collect the environmental background electric field signal of the non-interference detection area, and store the repeatedly collected environmental background electric field signal to the electroscope storage module to generate a zero-field signal template for interference suppression; a real-time running electric field signal acquisition module, used to start the non-contact electroscope to continuously collect the real-time running electric field signal of the area to be detected in a second state, wherein the second state is a charged environment; and a charged detection result acquisition module, used to perform bandpass filtering on the real-time running electric field signal to obtain a filtered running electric field signal, perform differential processing on the filtered running electric field signal based on the zero-field signal template, output a differential signal, and use the differential signal to acquire the charged detection result of the area to be detected.

[0013] The proposed interference suppression method and system for non-contact electroscopes involves: identifying a non-interference detection area in a non-energized environment; repeatedly acquiring the environmental background electric field signal of the non-interference detection area to generate a zero-field signal template for interference suppression; continuously acquiring real-time operating electric field signals in an energized environment using the non-contact electroscope; differentially processing the filtered operating electric field signal based on the zero-field signal template to output a differential signal, and using the differential signal to obtain the energized detection result of the area to be detected. This solves the technical problems in existing technologies where non-contact electroscopes are susceptible to interference from complex electromagnetic environments, leading to easy misjudgments and missed detections, and interference suppression is difficult to adapt to complex environmental changes, resulting in poor detection accuracy and reliability. The proposed method effectively suppresses interference, accurately identifies energized signals, and improves the detection accuracy and reliability of non-contact electroscopes. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments of this disclosure will be briefly described below. Flowcharts are used in this application to illustrate the operations performed by the system according to the embodiments of this application. It should be understood that the preceding or following operations are not necessarily performed precisely in sequence. Instead, various steps can be processed in reverse order or simultaneously as needed. Furthermore, other operations can be added to these processes, or one or more steps can be removed from these processes.

[0015] Figure 1 This is a schematic flowchart of an interference suppression method for a non-contact electroscope provided in an embodiment of this application.

[0016] Figure 2 This is a schematic diagram of the interference suppression system for a non-contact electroscope provided in an embodiment of this application.

[0017] Explanation of reference numerals in the attached diagram: Non-interference detection area identification module 10, zero-field signal template generation module 20, real-time running electric field signal acquisition module 30, and charged detection result acquisition module 40. Detailed Implementation

[0018] The above description is merely an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below.

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description of this application will be provided in conjunction with the accompanying drawings. The described embodiments should not be considered as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] In the following description, references to "some embodiments" describe a subset of all possible embodiments. However, it is understood that "some embodiments" can be the same or different subsets of all possible embodiments and can be combined with each other without conflict. The terms "first" and "second" are used merely to distinguish similar objects and do not represent a specific ordering of objects. The terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or server that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or modules not explicitly listed or inherent to these processes, methods, products, or devices. Unless otherwise defined, 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 application belongs. The terminology used herein is for the purpose of describing embodiments of this application only.

[0021] This application provides an interference suppression method for non-contact electroscopes, such as... Figure 1 As shown, the method includes: Step S100: In the first state, identify the non-interference detection area of ​​the area to be detected, wherein the first state is a non-electrical environment.

[0022] Preferably, before the electroscope begins detection, an environment free of charged objects (i.e., all surrounding objects are uncharged) is selected as the first state. In this state, the area to be detected is marked, and a non-interference detection area containing only the environmental background electric field (without target charged signals) is delineated. Specifically, the first state is a non-charged environment, meaning that there are no target charged objects in the area to be detected, such as unpowered equipment, lines, or areas that have been confirmed to be de-energized. This ensures that the electric field signal collected at this time only contains environmental background interference (such as natural static electricity, electromagnetic radiation, etc.) and does not contain actual charged signals. Then, through the positioning function of the electroscope (such as manual marking or automatic identification), a specific area is delineated in the non-charged environment as a reference area for interference suppression. The electric field signal in this area will be used to generate a zero-field signal template, i.e., an environmental background signal model in the ideal state (without charged objects).

[0023] Further, step S100 also includes step S110, detecting the area to be detected in the first state and performing an initial scan to obtain an initial electric field signal; step S120, performing stability verification and consistency verification on the initial electric field signal respectively, and marking it as a non-interference detection area if both verifications pass; step S130, wherein the stability verification is to determine whether the electric field amplitude of the initial electric field signal at the same scanning height is lower than a first preset interference tolerance threshold, and if the electric field amplitude of the initial electric field signal is lower than the first preset interference tolerance threshold, outputting a stability verification pass result; step S140, the consistency verification is to determine whether the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than a second preset interference tolerance threshold, and if the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than the second preset interference tolerance threshold, outputting a consistency verification pass result.

[0024] Preferably, in a non-charged environment (first state), dual verification (stability and consistency) ensures that the electric field signal in the selected area is only stable environmental background interference, without potential charged bodies or abnormal interference. Specifically, in a non-charged environment, an electroscope is used to perform a preliminary scan of the area to be tested (e.g., horizontal movement, scanning at different heights), and the initial electric field signal at each location is collected in real time (including environmental background interference, such as natural static electricity, stray fields from surrounding non-charged equipment, etc.), obtaining the electric field signal distribution data of the area at different locations and heights; then, the stability of the initial electric field signal is verified, i.e., in the same scan... At this altitude, the stability of the electric field amplitude of all sampling points within the altitude layer is analyzed. The first preset interference tolerance threshold is the maximum value of the environmental interference fluctuation that is allowed in advance. It is used to determine whether the signal belongs to stable background interference. If the electric field amplitude of all sampling points within the altitude layer is lower than the first threshold and the fluctuation range is within the tolerance, it indicates that the signal of the altitude layer is only composed of stable environmental background interference, without sudden strong interference or potential charged objects (charged objects usually generate electric fields with high amplitude or large fluctuations). This eliminates the influence of local strong interference in the same plane (such as temporarily placed static objects nearby), and then outputs the stability verification result.

[0025] Preferably, the initial electric field signal undergoes consistency verification. This involves comparing the differences in electric field amplitude at different scanning heights to determine if they conform to the characteristics of environmental background interference. A second preset interference tolerance threshold is the maximum allowable difference in signal between different heights, used to determine if the signal is uniform background interference. If the difference in electric field amplitude between different heights is lower than the second threshold, it indicates that the signals at different heights are consistent and conform to the characteristics of environmental background interference (such as a uniformly distributed electrostatic field in space). If the difference is too large, there may be vertical interference sources (such as hidden charged wires or induced electric fields). This eliminates potential vertical interference gradients, such as differences in electric field attenuation caused by charged bodies at different heights, and thus outputs the consistency verification result. Only when both stability verification and consistency verification pass, i.e., through the dual constraints of stable amplitude at the same height and small differences between different heights, ensuring that the electric field signal in this area is purely composed of uniform and stable environmental background interference without any charged bodies or abnormal interference, is the area to be detected identified as a non-interference detection area.

[0026] Step S200: Collect the ambient background electric field signal of the non-interference detection area multiple times, and store the collected ambient background electric field signal into the electroscope storage module to generate a zero-field signal template for interference suppression.

[0027] Step S200 further includes step S210, setting a preset sampling interval, and acquiring the environmental background electric field signal of the non-interference detection area N times based on the sampling interval; step S220, performing bandpass filtering on the environmental background electric field signal acquired each time to obtain the N acquired environmental background filtered electric field signals, extracting the amplitude and phase data corresponding to the N acquired environmental background filtered electric field signals to obtain N sets of amplitude and phase data; step S230, calculating the average value of the N sets of amplitude and phase data, and outputting the reference amplitude and reference phase; step S240, using the reference amplitude and reference phase to generate a zero-field signal template for interference suppression, and storing the zero-field signal template in the electroscope storage module.

[0028] Preferably, the preset sampling interval includes a pre-set time interval (e.g., 10ms / time) or a spatial interval (e.g., sampling once every 1cm movement) to ensure that the collected signals are independent and representative in time and space. Based on the sampling interval, N environmental background electric field signals are collected in the non-interference detection area, where N is a positive integer representing the preset number of times, such as N=100 times. Multiple samplings cover the random fluctuations of environmental background interference (e.g., instantaneous changes in natural static electricity, intermittent electromagnetic noise from surrounding equipment) and avoid the accidental errors of a single sampling. Then, bandpass filtering is performed on each acquired raw signal to filter out low-frequency interference (such as DC static electricity) and high-frequency noise (such as radio frequency signals), retaining only the signal within the target detection frequency band. For example, the characteristic frequency band for live detection of power equipment is near the 50Hz / 60Hz power frequency, resulting in N acquired environmental background filtered electric field signals. Next, the amplitude and phase data corresponding to the N acquired environmental background filtered electric field signals are extracted. The amplitude is the intensity of the electric field signal (e.g., mV / m), reflecting the energy of the interference signal, and the phase is the phase angle of the signal waveform (e.g., 0°~360°), reflecting the timing characteristics of the interference signal. Finally, N sets of amplitude and phase data are generated.

[0029] Preferably, the arithmetic mean of N sets of amplitude data is calculated, and the average amplitude is used as the reference amplitude to represent the average energy level of environmental background interference in the target frequency band. The vector mean of N sets of phase data is calculated, such as by calculating the phase mean through complex number operations, and the average phase is used as the reference phase to represent the average phase characteristics of environmental background interference in the target frequency band. Then, the reference amplitude and reference phase are combined to form a standardized signal model, which is used as the zero-field signal template for interference suppression. Finally, it is stored in the electroscope storage module. During live detection, the amplitude and phase of the real-time signal are differentially calculated with the zero-field signal template to remove background interference. For example, if the phase deviation between the real-time signal and the zero-field signal template is large (such as exceeding the preset tolerance), it can be determined as a real live signal (the phase of the electric field generated by the live body is usually different from the background interference). Furthermore, if the detection environment changes (such as from indoors to outdoors), the non-interference area can be scanned again and the zero-field signal template can be generated again, so that the electroscope can adapt to the background interference characteristics of different scenarios, avoid the limitations of fixed templates, and thus improve the detection reliability in complex environments.

[0030] In step S300, the non-contact electroscope is activated in the second state to continuously collect the real-time operating electric field signal of the area to be tested. The second state is a charged environment.

[0031] Preferably, the second state is a charged environment, which means that there is a target charged body (such as a normally operating power transmission line, energized electrical equipment, etc.) in the area to be detected or an area that needs to be determined to be charged (such as the casing of equipment suspected of leakage, or a line that has not been clearly de-energized). Then, in this state, by collecting real-time electric field signals, it is determined whether the area to be detected is charged, or the electric field distribution characteristics (such as amplitude, phase, etc.) of the charged body are detected. Specifically, the non-contact electroscope continuously collects the real-time operating electric field signal of the area to be detected at a preset frequency (such as 100 times per second), including signal collection at different spatial positions (such as horizontal moving scan) and different heights (such as vertical layered detection), forming multi-dimensional electric field data. The real-time operating electric field signal simultaneously contains the target charged signal (such as power frequency electric field) and environmental background interference.

[0032] Step S400: Bandpass filtering is performed on the real-time operating electric field signal to obtain a filtered operating electric field signal. Differential processing is performed on the filtered operating electric field signal based on the zero-field signal template to output a differential signal. The charged detection result of the area to be detected is obtained using the differential signal.

[0033] Preferably, a bandpass filter is applied to the real-time operating electric field signal to perform bandpass filtering processing, allowing only signals in the target detection frequency band (such as power frequency 50Hz / 60Hz and its harmonics) to pass through, filtering out low-frequency (such as DC static electricity, environmental electromagnetic noise) and high-frequency (such as radio frequency noise, radio waves, equipment switching transients) interference, thus obtaining a filtered operating electric field signal; then, differential processing is performed on the filtered operating electric field signal based on the zero-field signal template, that is, the amplitude and phase of the filtered real-time signal are subtracted point by point from the signal of the zero-field signal template, which significantly cancels out background interference components, obtaining a differential signal, which mainly reflects the characteristics of the target charged signal. Specifically, the difference between the amplitude of the real-time signal and the amplitude of the template signal is calculated, and if the amplitude difference is greater than a threshold, it is considered that the target charged signal exists; the phase of the real-time signal is calculated. The phase difference between the differential signal and the template signal is used to further confirm the presence of a charged target signal if the phase difference exceeds the natural fluctuation range of background interference. The threshold can be dynamically adjusted according to the environment (e.g., increasing the threshold when background interference fluctuations are large) to avoid misjudgment caused by background fluctuations. If the amplitude difference of the differential signal is close to 0 and the phase difference is stable within the background fluctuation range, it is determined that there is no charged body, indicating that the real-time signal is highly matched with the template and that only background interference exists. Finally, the charged detection result of the area to be detected is generated, which may be charged / uncharged, or the amplitude and phase of the differential signal, to assess the charging intensity or fault severity, thereby achieving the goal of accurately stripping the charged signal from the complex electromagnetic environment, achieving accurate cancellation of interference from the same source, and improving the accuracy and reliability of non-contact electroscope detection.

[0034] Furthermore, step S400 also includes step S401, obtaining the real-time status of each device in the area to be detected, including running time, running temperature and running position; step S402, when the real-time status of any device in the area to be detected changes, the update mechanism is activated to obtain the updated zero-field signal template, and the filtered running electric field signal is differentially processed according to the updated zero-field signal template to output the differential signal.

[0035] Preferably, the real-time status of each device in the area to be tested is acquired, including runtime, operating temperature, and operating position. Runtime is the cumulative time the device has been powered on and running; for example, a transformer running continuously for 10 hours may cause changes in the surrounding electric field due to heat generation. Operating temperature is the surface or internal temperature of the device; for example, overheating of a motor may cause ionization of the insulating material, generating additional electric field interference. Operating position is the change in the physical location of the device; for example, moving a live device closer to the testing area alters the background interference distribution. When the real-time status of any device in the area to be tested changes, such as a runtime exceeding T hours (e.g., T=24 hours, triggering a periodic template update), an operating temperature exceeding θ℃ (e.g., θ=60℃, high temperature may be accompanied by abnormal electric field), or a device moving more than D meters (e.g., D=1 meter, short-distance movement may introduce new interference sources), the template update mechanism is triggered.

[0036] Preferably, the update mechanism is initiated to obtain the updated zero-field signal template. Specifically, the area to be detected is switched to the first state (temporary non-energized environment). For example, the device can be powered off, and the power supply is temporarily cut off to make the detection area a non-energized environment. Alternatively, if the power cannot be powered off, the device's energized signal is shielded by an algorithm to approximate a non-energized environment. Then, the stability and consistency of the electric field signal in the area to be detected are verified, and a clean background area is redefined. Next, the background electric field signal in the new environment is collected at a preset sampling interval. After bandpass filtering and amplitude / phase averaging, the updated zero-field signal template is generated. Finally, the filtered operating electric field signal is differentially processed according to the updated zero-field signal template. That is, the amplitude and phase of the filtered real-time signal are subtracted point by point from the signal of the updated zero-field signal template to significantly cancel out background interference components and output a differential signal, thereby improving the detection accuracy and reliability of the non-contact electroscope in complex environments.

[0037] Furthermore, step S400 also includes step S410, which uses DPLL technology to synchronize the filtered operating electric field signal with the zero-field signal template to obtain a synchronization signal group; step S420, which performs multi-dimensional differential processing on the two signals of the synchronization signal group, including time-domain differential, frequency-domain differential and feature space differential, to obtain time-domain differential signal, frequency-domain differential signal and feature space differential signal; step S430, which performs weighted fitting of the time-domain differential signal, frequency-domain differential signal and feature space differential signal to output a differential signal.

[0038] Preferably, signal synchronization is achieved through a digital phase-locked loop (DPLL), and differences are extracted from three dimensions: time domain, frequency domain, and feature space, improving the separation accuracy of charged signals and interference. The DPLL is a closed-loop control system that tracks the frequency and phase of the input signal, used to solve the frequency deviation and phase drift between the filtered operating electric field signal and the zero-field signal template. Specifically, based on DPLL technology, the filtered operating electric field signal and the zero-field signal template are synchronized. This involves using the DPLL to detect the frequency difference between the two signals, adjusting the template signal frequency using a numerically controlled oscillator (NCO) to match the real-time signal frequency, calculating the phase difference using a phase detector (PD), generating a control signal via a loop filter (LF), driving the NCO to adjust the template phase, aligning the two signals, and outputting a synchronization signal group containing the real-time signal and the template signal with the same frequency and aligned phase.

[0039] Preferably, the two signals of the synchronization signal group are subjected to multi-dimensional differential processing, including time-domain differential, frequency-domain differential, and feature space differential. Specifically, time-domain differential directly compares the differences in signal waveforms, that is, it calculates the amplitude difference of the synchronization signal group point by point on the time axis to obtain the time-domain differential signal; frequency-domain differential analyzes the differences in frequency components, that is, it performs Fast Fourier Transform (FFT) on the synchronization signal group to obtain the real-time signal spectrum and the template spectrum, calculates the frequency-domain difference, retains the frequency components with significant differences, and outputs the frequency-domain differential signal; feature space differential extracts the differences in higher-order statistical features, that is, it constructs the feature vectors of the real-time signal and the template, calculates the feature space distance (such as Euclidean distance, cosine similarity), captures the deep differences in signal waveform complexity, energy distribution, etc., and uses them as the feature space differential. Finally, the time-domain difference signal, frequency-domain difference signal, and feature space difference signal are weighted and fitted. The weighting coefficients are dynamically adjusted according to the detection scenario. For example, power frequency detection focuses on time-domain difference and frequency-domain difference, while partial discharge detection focuses on frequency-domain difference and feature space difference. The final output is a difference signal.

[0040] Furthermore, step S400 also includes step S440, obtaining a preset power frequency signal feature threshold; step S450, performing sliding window detection on the differential signal based on the preset power frequency signal feature threshold, extracting an abnormal fluctuation window and an abnormal fluctuation index of the abnormal fluctuation window, wherein the abnormal fluctuation index is obtained by detecting the peak value and skewness of the signal; step S460, combining the abnormal fluctuation index of the abnormal fluctuation window to obtain the live detection result of the area to be detected.

[0041] Preferably, a preset power frequency signal characteristic threshold is obtained. This threshold is set based on power standards and historical detection data, serving as a basis for determining whether the signal is abnormal. It includes an amplitude threshold (the safe critical value for a normal power frequency electric field), a peak value threshold (the ratio of the signal peak value to the effective value), and a skewness threshold (an indicator of the asymmetry in the signal probability distribution). Then, a sliding window detection is performed on the differential signal using the preset power frequency signal characteristic threshold. This involves dividing the continuous differential signal into multiple fixed-length windows (e.g., each window is 100ms), and comparing each window with the preset power frequency signal characteristic threshold. If the signal characteristics (e.g., peak value, skewness) within a certain window exceed the preset threshold range, it is determined to be an abnormal fluctuation window. For example, if the signal peak value in a certain window reaches ±15kV / m (exceeding the threshold ±10kV / m), or the absolute value of the skewness is greater than 0.5 (deviating from the normal symmetrical waveform), it is marked as abnormal to locate the time interval of the abnormality. The abnormal fluctuation window and the abnormal fluctuation index of the abnormal fluctuation window are extracted. The abnormal fluctuation index is obtained by detecting the signal peak value and skewness. The signal peak value is the maximum amplitude of the signal within the window (such as the maximum value of the voltage intensity). The peak value change may reflect sudden faults such as partial discharge and equipment breakdown. Skewness measures the degree to which the signal waveform deviates from the symmetrical distribution (the skewness of the normal distribution is 0). Abnormal skewness may indicate electric field distortion, such as asymmetric discharge caused by surface charge accumulation of equipment and insulation aging.

[0042] Preferably, the final determination of whether the energized state is transient (e.g., the instant a switch is closed) or steady-state (e.g., a line is energized for a long time) is made by analyzing the time distribution of continuous abnormal windows, and the energized detection results of the area to be detected are obtained, as shown in Table 1.

[0043] Furthermore, step S460 also includes step S461, detecting the historical operating conditions of the equipment in the area to be detected, classifying the operating modes of the equipment in the area to be detected according to the historical operating conditions, and outputting multiple operating modes; step S462, setting multiple preset power frequency signal feature thresholds corresponding to the multiple operating modes; step S463, obtaining the matching power frequency signal feature thresholds based on the real-time operating electric field signal of the area to be detected, performing sliding window detection on the differential signal based on the matching power frequency signal feature thresholds, and updating the live detection results.

[0044] Preferably, the operating conditions of power equipment affect the characteristics of its normal electric field signal. Historical operating conditions of the equipment in the area to be tested are collected, including operating parameters (running time, load rate, ambient temperature, RMS voltage / current, etc.) and signal characteristics (peak value, frequency, skewness, etc. of historical power frequency electric field signal). Then, the operating modes of the equipment in the area to be tested are classified according to historical operating conditions, i.e., the operating states of the equipment are clustered based on the similarity of operating conditions, and divided into multiple operating modes, such as low load mode, normal load mode, and high load mode. Multiple preset power frequency signal characteristic thresholds are set for each operating mode. In the high load mode, the internal electric field strength of the equipment may naturally increase due to the increase in current, and slight heating of the insulation material may cause a slight change in waveform symmetry. Therefore, the thresholds are appropriately relaxed; for example, in the low load mode, the peak threshold is ±8~±10kV / m, and the skewness... The threshold is -0.2 to +0.2; in high-load mode, the peak threshold is ±12 to ±14 kV / m, and the skewness threshold is -0.4 to +0.4. Then, based on the real-time operating electric field signal of the area to be detected, it is determined which operating mode it belongs to (e.g., if the load rate is detected at 80%, it is determined to be high-load mode). The corresponding matching power frequency signal characteristic threshold is obtained, and the differential signal is detected window by window using the matching threshold to determine whether there is any abnormality. For example, in high-load mode, if the peak value of a certain window is +13 kV / m, it is within the threshold allowable range (±12 to ±14 kV / m) and is determined to be normal. If the same peak value appears in low-load mode (threshold ±8 to ±10 kV / m), it is determined to be abnormal fluctuation. Finally, the live detection results are updated based on the window detection results, thereby reducing the false alarm rate and the missed alarm rate, and improving the accuracy and reliability of non-contact voltage detector detection.

[0045] In the above text, refer to Figure 1 An interference suppression method for a non-contact electroscope according to an embodiment of the present invention is described in detail. Next, reference will be made to... Figure 2 An interference suppression system for a non-contact electroscope is described according to an embodiment of the present invention.

[0046] The interference suppression system for non-contact electroscopes according to embodiments of the present invention addresses the technical problems in the prior art where non-contact electroscopes are susceptible to interference from complex electromagnetic environments, leading to easy misjudgments and missed detections, and the interference suppression system is difficult to adapt to complex environmental changes, resulting in poor detection accuracy and reliability. The system effectively suppresses interference, accurately identifies charged signals, and improves the detection accuracy and reliability of non-contact electroscopes. Figure 2 As shown, the interference suppression system for non-contact electroscopes includes: a non-interference detection area identification module 10, a zero-field signal template generation module 20, a real-time running electric field signal acquisition module 30, and a live detection result acquisition module 40.

[0047] The non-interference detection area identification module 10 is used to identify the non-interference detection area of ​​the area to be detected in a first state, wherein the first state is a non-charged environment; the zero-field signal template generation module 20 is used to repeatedly collect the environmental background electric field signal of the non-interference detection area, and store the repeatedly collected environmental background electric field signal to the electroscope storage module to generate a zero-field signal template for interference suppression; the real-time running electric field signal acquisition module 30 is used to start the non-contact electroscope to continuously collect the real-time running electric field signal of the area to be detected in a second state, wherein the second state is a charged environment; the charged detection result acquisition module 40 is used to perform bandpass filtering on the real-time running electric field signal to obtain a filtered running electric field signal, perform differential processing on the filtered running electric field signal based on the zero-field signal template, output a differential signal, and obtain the charged detection result of the area to be detected using the differential signal.

[0048] The specific configuration of the zero-field signal template generation module 20 will be described in detail below. The zero-field signal template generation module 20 further includes: a preset sampling interval; acquiring the environmental background electric field signal of the non-interference detection area N times based on the sampling interval; performing bandpass filtering on each acquired environmental background electric field signal to obtain N acquired environmental background filtered electric field signals; extracting the amplitude and phase data corresponding to the N acquired environmental background filtered electric field signals to obtain N sets of amplitude and phase data; calculating the average value of the N sets of amplitude and phase data to output a reference amplitude and reference phase; combining the reference amplitude and reference phase to generate a zero-field signal template for interference suppression; and storing the zero-field signal template in the electroscope storage module.

[0049] The specific configuration of the live-line detection result acquisition module 40 will be described in detail below. The live-line detection result acquisition module 40 further includes: acquiring the real-time status of each device in the area to be detected, including running time, running temperature, and running position; when the real-time status of any device in the area to be detected changes, activating the update mechanism to obtain an updated zero-field signal template; performing differential processing on the filtered operating electric field signal based on the updated zero-field signal template; and outputting a differential signal.

[0050] The specific configuration of the non-interference detection area identification module 10 will be described in detail below. The non-interference detection area identification module 10 further includes: in a first state, detecting the area to be detected by initial scanning to obtain an initial electric field signal; performing stability verification and consistency verification on the initial electric field signal respectively, and identifying it as a non-interference detection area if both verifications pass; wherein, the stability verification is to determine whether the electric field amplitude of the initial electric field signal at the same scanning height is lower than a first preset interference tolerance threshold; if the electric field amplitude of the initial electric field signal is lower than the first preset interference tolerance threshold, outputting a stability verification pass result; the consistency verification is to determine whether the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than a second preset interference tolerance threshold; if the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than the second preset interference tolerance threshold, outputting a consistency verification pass result.

[0051] The specific configuration of the charged detection result acquisition module 40 will be described in detail below. The charged detection result acquisition module 40 further includes: synchronizing the filtered operating electric field signal with the zero-field signal template based on DPLL technology to obtain a synchronization signal group; performing multi-dimensional differential processing on the two signals of the synchronization signal group, including time-domain differential, frequency-domain differential, and feature space differential, to obtain a time-domain differential signal, a frequency-domain differential signal, and a feature space differential signal; and weighted fitting of the time-domain differential signal, the frequency-domain differential signal, and the feature space differential signal to output a differential signal.

[0052] The specific configuration of the live-line detection result acquisition module 40 will be described in detail below. The live-line detection result acquisition module 40 further includes: acquiring a preset power frequency signal characteristic threshold; performing sliding window detection on the differential signal based on the preset power frequency signal characteristic threshold, extracting an abnormal fluctuation window and an abnormal fluctuation index of the abnormal fluctuation window, the abnormal fluctuation index being obtained by detecting the signal peak value and skewness; and combining the abnormal fluctuation index of the abnormal fluctuation window to obtain the live-line detection result of the area to be detected.

[0053] The specific configuration of the live-line detection result acquisition module 40 will be described in detail below. The live-line detection result acquisition module 40 further includes: detecting the historical operating conditions of the equipment in the area to be detected; classifying the operating modes of the equipment in the area to be detected according to the historical operating conditions; outputting multiple operating modes; setting multiple preset power frequency signal characteristic thresholds corresponding to the multiple operating modes; acquiring matching power frequency signal characteristic thresholds based on the real-time operating electric field signal of the area to be detected; performing sliding window detection on the differential signal based on the matching power frequency signal characteristic thresholds; and updating the live-line detection result.

[0054] The interference suppression system for non-contact electroscopes provided in this embodiment of the invention can execute the interference suppression method for non-contact electroscopes provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0055] Although this application makes various references to certain modules in the system according to the embodiments of this application, any number of different modules can be used and run on user terminals and / or servers. The various units and modules included are only divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be achieved; in addition, the specific names of each functional unit are only for easy distinction between each other and are not used to limit the scope of protection of this invention.

[0056] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Those skilled in the art should understand that various modifications, combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An interference suppression method for non-contact electroscopes, characterized in that, The method includes: In the first state, a non-interference detection area is identified for the area to be detected, wherein the first state is a non-electrical environment; The environmental background electric field signal of the non-interference detection area is collected multiple times, and the collected environmental background electric field signal is stored in the electroscope storage module to generate a zero-field signal template for interference suppression. In the second state, a non-contact electroscope is activated to continuously collect the real-time operating electric field signal of the area to be detected. The second state is a charged environment. The real-time operating electric field signal is bandpass filtered to obtain a filtered operating electric field signal. The filtered operating electric field signal is then differentially processed based on the zero-field signal template to output a differential signal. The charged detection result of the region to be detected is obtained using the differential signal.

2. The interference suppression method for a non-contact electroscope as described in claim 1, characterized in that, The method involves storing the environmental background electric field signals collected multiple times into the electroscope storage module to generate a zero-field signal template for interference suppression. A preset sampling interval is used to collect the environmental background electric field signal of the non-interference detection area N times based on the sampling interval; The ambient background electric field signal acquired each time is bandpass filtered to obtain N acquired ambient background filtered electric field signals. The amplitude and phase data corresponding to the N acquired ambient background filtered electric field signals are extracted to obtain N sets of amplitude and phase data. The average value of the N sets of amplitude and phase data is calculated, and the reference amplitude and reference phase are output. A zero-field signal template for interference suppression is generated by combining the reference amplitude and reference phase, and the zero-field signal template is stored in the electroscope storage module.

3. The interference suppression method for a non-contact electroscope as described in claim 1, characterized in that, The zero-field signal template is updated through an update mechanism, which includes: Obtain the real-time status of each device in the area to be detected, including runtime, operating temperature, and operating location; When the real-time status of any device in the detection area changes, the update mechanism is activated to obtain an updated zero-field signal template. The filtered operating electric field signal is then differentially processed based on the updated zero-field signal template to output a differential signal.

4. The interference suppression method for a non-contact electroscope as described in claim 1, characterized in that, In the first state, the method for identifying the non-interference detection area of ​​the region to be detected includes: In the first state, the area to be detected is initially scanned to obtain the initial electric field signal; The initial electric field signal was subjected to stability verification and consistency verification respectively. If both verifications were passed, the region was marked as a non-interference detection area. The stability verification involves determining whether the electric field amplitude of the initial electric field signal is lower than a first preset interference tolerance threshold at the same scanning height. If the electric field amplitude of the initial electric field signal is lower than the first preset interference tolerance threshold, the stability verification result is output. The consistency verification is to determine whether the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than the second preset interference tolerance threshold. If the difference in electric field amplitude of the initial electric field signal at different scanning heights is lower than the second preset interference tolerance threshold, the consistency verification result is output.

5. The interference suppression method for a non-contact electroscope as described in claim 1, characterized in that, The method involves differential processing of the filtered operating electric field signal based on the zero-field signal template to output a differential signal, including: Based on DPLL technology, the filtered operating electric field signal is synchronized with the zero field signal template to obtain a synchronization signal group; The two signals of the synchronization signal group are subjected to multidimensional differential processing, including time-domain differential, frequency-domain differential and feature space differential, to obtain time-domain differential signal, frequency-domain differential signal and feature space differential signal; The time-domain difference signal, frequency-domain difference signal, and feature space difference signal are weighted and fitted to output a difference signal.

6. The interference suppression method for a non-contact electroscope as described in claim 1, characterized in that, The method for obtaining the charged detection result of the region to be detected using the differential signal includes: Obtain the preset power frequency signal characteristic threshold; The differential signal is subjected to sliding window detection at the preset power frequency signal characteristic threshold to extract abnormal fluctuation windows and abnormal fluctuation indicators of the abnormal fluctuation windows. The abnormal fluctuation indicators are obtained by detecting the peak value and skewness of the signal. By combining the abnormal fluctuation index of the abnormal fluctuation window, the charged detection result of the area to be detected is obtained.

7. The interference suppression method for a non-contact electroscope as described in claim 6, characterized in that, The method includes: The historical operating conditions of the equipment in the area to be tested are detected, and the operating modes of the equipment in the area to be tested are classified according to the historical operating conditions, and multiple operating modes are output. Set multiple preset power frequency signal characteristic thresholds corresponding to the multiple working modes; Based on the real-time operating electric field signal of the area to be detected, a matching power frequency signal feature threshold is obtained. Based on the matching power frequency signal feature threshold, a sliding window detection is performed on the differential signal to update the energized detection result.

8. An interference suppression system for non-contact electroscopes, characterized in that, The system is used to implement the interference suppression method for a non-contact electroscope according to any one of claims 1 to 7, the system comprising: The non-interference detection area marking module is used to mark the non-interference detection area of ​​the area to be detected in a first state, wherein the first state is a non-electrical environment. The zero-field signal template generation module is used to repeatedly collect the environmental background electric field signal of the non-interference detection area, and store the repeatedly collected environmental background electric field signal into the electroscope storage module to generate a zero-field signal template for interference suppression. A real-time electric field signal acquisition module is used to activate a non-contact electroscope in the second state to continuously acquire the real-time electric field signal of the area to be detected, where the second state is a charged environment. The charged detection result acquisition module is used to perform bandpass filtering on the real-time operating electric field signal to obtain a filtered operating electric field signal, perform differential processing on the filtered operating electric field signal based on the zero-field signal template, output a differential signal, and use the differential signal to acquire the charged detection result of the area to be detected.

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