Cable pairing method and system based on magnetic field signal detection

Abstract

The invention discloses a cable pairing method and system based on magnetic field signal detection, and the method comprises the steps: S1, respectively installing magnetic field signal detectors at two ends of a cable, and obtaining magnetic field signals at the two ends of the cable; s2, sequentially performing signal amplification, filtering and digital processing on the magnetic field signals at the two ends of the cable, and transmitting the magnetic field signals to a data aligner; s3, based on the data aligner, performing time synchronization and feature matching on the two magnetic field signals after digital processing; and S4, if the two magnetic field signal features are successfully matched, indicating that the magnetic field signals are aligned, judging that the cable pairing is successful, and outputting a matching result, so that the cable can be quickly detected without disassembling the cable, thereby realizing the quick cable pairing, reducing the troubleshooting time and improving the pairing accuracy.

Description

Technical Field

[0001] The present application relates to the field of power monitoring technology, and in particular to a cable pairing method and system based on magnetic field signal detection. Background Art

[0002] As a vital component of the power system, power cables play a crucial role in the transmission and distribution of electrical energy. As power systems evolve towards higher reliability and efficiency, cable health monitoring and maintenance have become critical to ensuring stable operation. However, traditional cable inspection and matching methods rely primarily on regular physical inspections and localized electrical testing. These methods are not only time-consuming and labor-intensive, but also often fail to detect minor damage or early signs of aging within the cable, increasing the risk of potential cable failure.

[0003] Existing cable identification methods typically rely on cable marking, electrical testing, or manual troubleshooting. These methods only support de-energized cables and cannot be paired with energized cables. Furthermore, they require pre-marked cables, making them inapplicable to unmarked scenarios. Therefore, a non-destructive, efficient, and accurate cable pairing device is urgently needed to address these issues. Summary of the Invention

[0004] In response to the defects in the existing technology, the present application provides a cable pairing method and system based on magnetic field signal detection to solve the problem that the existing detection and matching methods are difficult to meet the inspection and matching requirements under energized working conditions and cannot be applied to unmarked scenarios.

[0005] To achieve the above objectives, the present application provides a cable pairing method based on magnetic field signal detection, comprising:

[0006] S1. Installing magnetic field signal detectors at both ends of the cable to obtain magnetic field signals at both ends of the cable;

[0007] S2, sequentially amplifying, filtering, and digitizing the magnetic field signals at both ends of the cable, and transmitting the signals to a data aligner;

[0008] S3. Based on the data aligner, performing time synchronization and feature matching on the two digitized magnetic field signals;

[0009] S4. If the two magnetic field signal features match successfully, it indicates that the magnetic field signals are aligned, and it is determined that the cables are paired successfully, and a matching result is output.

[0010] Furthermore, S3, based on the data aligner, the step of performing time synchronization and feature matching on the two digitized magnetic field signals specifically includes:

[0011] S31, performing time synchronization on the two digitally processed magnetic field signals;

[0012] S32, calculating dynamic statistical features based on a signal matching algorithm;

[0013] S33: Based on a preset correlation threshold, performing alignment judgment on the dynamic statistical features.

[0014] Furthermore, S32, the step of calculating dynamic statistical features based on the signal matching algorithm, specifically includes:

[0015] Performing short-time Fourier transform on the two digitally processed magnetic field signals to obtain dynamic change characteristics;

[0016] Based on the preset frequency band, the time-frequency energy concentration is extracted and the dynamic statistical characteristics are calculated;

[0017] Based on the dynamic statistical characteristics, the autoregressive coefficient and the sample entropy are determined.

[0018] Furthermore, S33, the step of determining the alignment of the dynamic statistical features based on a preset correlation threshold, specifically includes:

[0019] Align the time axis of the signals collected at both ends;

[0020] Calculate the time delay and cross-correlation value of two signals through the cross-correlation function;

[0021] Finding a peak value and a maximum delay of the cross-correlation value based on the cross-correlation value;

[0022] Based on the maximum delay, compensating for the phase offset at both ends of the cable to determine an optimal alignment delay time difference;

[0023] If the correlation of the optimal alignment delay time difference is greater than or equal to a preset correlation threshold, it indicates that the alignment of the magnetic field signals is reliable.

[0024] Furthermore, the step of calculating the time delay and the cross-correlation value of the two signals by using the cross-correlation function specifically includes:

[0025] Selecting a signal within a time window from the two magnetic field signals, and calculating the Pearson correlation coefficient r of the two magnetic field signals at the optimal alignment delay time difference;

[0026] If the Pearson correlation coefficient r is less than a preset correlation threshold, the alignment does not meet the requirements and the two cables are determined to belong to different cables.

[0027] Furthermore, S2, sequentially amplifying, filtering, and digitizing the magnetic field signals at both ends of the cable, and transmitting the signals to a data aligner, specifically includes:

[0028] Acquiring a magnetic field signal around the cable and performing pre-gain amplification to suppress common-mode noise and DC drift;

[0029] Filtering and digitally processing the magnetic field signal after the pre-gain amplification to convert the continuous magnetic field signal into a discrete time series, wherein the filtering frequency of the digital processing is less than or equal to half of the sampling frequency;

[0030] Performing gain calibration and zero point calibration on the discrete time series after digitization.

[0031] Furthermore, the magnetic field signal detector and the data aligner perform data transmission via wireless communication.

[0032] Furthermore, before S1, installing magnetic field signal detectors at both ends of the cable and obtaining magnetic field signals at both ends of the cable, the cable pairing method based on magnetic field signal detection further includes:

[0033] Select a shielding cover that matches the diameter of the cable and fix the shielding cover tightly against the surface of the cable.

[0034] The present application also provides a cable pairing system based on magnetic field signal detection, the cable pairing system based on magnetic field signal detection comprising:

[0035] A magnetic field signal detector, used to obtain a magnetic field signal at the end of the cable;

[0036] A signal processing component, configured to sequentially amplify, filter, and digitize the magnetic field signal;

[0037] a data aligner, configured to perform time synchronization and feature matching on the magnetic field signal;

[0038] The communication module is used to transmit the digitally processed magnetic field signal to the data aligner.

[0039] Furthermore, the magnetic field signal detector is annular, and a plurality of magnetic field sensors are provided inside the magnetic field signal detector.

[0040] Compared with the prior art, the advantages of this application are:

[0041] The present application installs magnetic field signal detectors at both ends of the cable to obtain magnetic field signals at both ends of the cable, amplifies, filters and digitizes the magnetic field signals at both ends of the cable in sequence, and transmits them to a data aligner. Based on the data aligner, the two digitized magnetic field signals are time synchronized and feature matched, so that detection can be performed without disassembling the cable. The application is suitable for cables working under power. Due to the magnetic field detection of the magnetic field signal detector and the time synchronization and feature matching of the data aligner, cable pairing is quickly achieved, which reduces manual troubleshooting time and improves pairing accuracy. It can meet the needs of complex application scenarios with multiple cables running in parallel. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 creative work.

[0043] Figure 1 Schematic diagram of a flow chart of a cable pairing method based on magnetic field signal detection according to an embodiment of the present application. DETAILED DESCRIPTION

[0044] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0045] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, combined, or partially merged, so the actual execution order may vary depending on the actual situation.

[0046] In the description of this application, the terms "first / second" are only used to distinguish similar objects and do not represent a specific order for the objects. It can be understood that "first / second" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0047] It should be understood that the orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings. These orientation terms are only used to facilitate the description of this application and simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they should not be understood as limiting this application.

[0048] In the fields of power, communications, etc., cable identification and pairing is an important but complex task. Traditional cable identification methods usually rely on cable marking, electrical testing or manual troubleshooting, which has the following disadvantages: (1) Limited use scenarios: only supports non-live cables, and cables cannot be paired under energized working conditions; (2) Strong labeling dependency: cables need to be pre-marked and cannot be applied to unmarked scenarios; (3) Destructive testing: some methods require disassembly of cables or electrical testing, which affects the normal use of cables; (4) Low efficiency: in scenarios with multiple cables in parallel and complex layouts, manual troubleshooting is time-consuming and prone to errors. Therefore, there is an urgent need for a non-destructive, efficient and accurate cable pairing device to solve the above problems.

[0049] Application scenarios of the device include: (1) Quickly pairing cables that have been put into use in power maintenance; (2) Identifying multiple cables in complex arrangements in factories or buildings; (3) Verifying the correct connection of cables during cable manufacturing or installation. Figure 1 FIG. 1 is a flow chart of a cable pairing method based on magnetic field signal detection according to an embodiment of the present application. Figure 1 As shown, an embodiment of the present application provides a cable pairing method based on magnetic field signal detection, including:

[0050] S1. Installing magnetic field signal detectors at both ends of the cable to obtain magnetic field signals at both ends of the cable;

[0051] S2, sequentially amplifying, filtering, and digitizing the magnetic field signals at both ends of the cable, and transmitting the signals to a data aligner;

[0052] S3. Based on the data aligner, performing time synchronization and feature matching on the two digitized magnetic field signals;

[0053] S4. If the two magnetic field signal features match successfully, it indicates that the magnetic field signals are aligned, and it is determined that the cables are paired successfully, and a matching result is output.

[0054] Specifically, select a suitable magnetic field signal detector to ensure that it can accurately detect magnetic field changes, and install a magnetic field signal detector at each end of the cable. During installation, ensure that the detector is in close contact with the magnetic medium of the cable to accurately capture the magnetic field signal.

[0055] The magnetic field signals collected by the detectors at both ends of the cable are connected to a signal amplification circuit to increase the signal amplitude for subsequent processing. A filtering circuit is then applied to remove noise and interference from the magnetic field signal, preserving the desired original signal. The amplified and filtered signal undergoes A / D conversion (analog-to-digital conversion) to convert it into a digital signal for processing and analysis by electronic equipment.

[0056] The digitized magnetic field signal is transmitted to a data aligner, and the data aligner is used to synchronize the two digitized magnetic field signals in time to ensure that they are analyzed under the same time reference. A feature matching algorithm, such as correlation coefficient analysis, template matching, etc., is used to compare the features of the two signals to determine whether they match. If the matching degree of the two magnetic field signals exceeds the set threshold after feature matching, it is considered that the magnetic field signal feature matching is successful. By determining that the magnetic field signal alignment is successful, it is further determined that the cable pairing is successful, and the matching result is output. The matching result can display the pairing status through an indicator light, a sound prompt, or on a display screen. In particular, data transmission is performed between the magnetic field signal detector and the data aligner via wireless communication.

[0057] In order to improve pairing accuracy and reliability, adaptive filtering technology can also be applied in the implementation to adapt to different electromagnetic environments and cable characteristics, and a calibration step can be introduced to regularly check the performance of the magnetic field signal detector to ensure signal quality.

[0058] To better understand the principle of cable pairing based on magnetic field signal detection in the embodiment of the present application, a magnetic field signal detector is installed at each end of the cable to detect the magnetic field signal inside the cable. The detected magnetic field signal is sequentially amplified, filtered, and digitized before being transmitted to a data aligner. The data aligner performs time synchronization and feature matching on the two signal segments to determine whether they originate from the same cable. If the signals are aligned, the cable pairing is determined to be successful and the result is output through a display module. For example, the magnetic field signal detector adopts a ring structure with multiple high-sensitivity magnetic field sensors (TMR or fluxgate sensors) arranged inside. The magnetic field signal detector is equipped with a metal shield of various sizes to shield external electromagnetic interference and is close to the cable surface for magnetic field detection. The data aligner receives and processes data from the two magnetic field signal detectors and determines whether the signals at both ends are aligned through time synchronization and signal matching algorithms to achieve cable pairing. The implementation process of the data aligner includes: receiving data from the two magnetic field signal detectors; performing time synchronization on the two signal segments to ensure that the data acquisition time is consistent; using a signal matching algorithm (such as time domain waveform comparison and frequency domain feature analysis) to determine whether the signals are aligned; if the signals are aligned, the cable pairing is determined to be successful and the result is output through a display module.

[0059] It should be noted that compared with the existing technology, the present application obtains the magnetic field signals at both ends of the cable by installing magnetic field signal detectors at both ends of the cable, amplifies, filters and digitizes the magnetic field signals at both ends of the cable in turn, and transmits them to the data aligner. Based on the data aligner, the two digitized magnetic field signals are time synchronized and feature matched, so that detection can be performed without disassembling the cable. It is suitable for cables working under power. Due to the magnetic field detection of the magnetic field signal detector and the time synchronization and feature matching of the data aligner, cable pairing is quickly achieved, which reduces manual troubleshooting time and improves pairing accuracy. It can meet the needs of multiple cables in parallel and complex application scenarios.

[0060] In some embodiments, S3, based on the data aligner, performing time synchronization and feature matching on the two digitized magnetic field signals, specifically includes:

[0061] S31, performing time synchronization on the two digitally processed magnetic field signals;

[0062] S32, calculating dynamic statistical features based on a signal matching algorithm;

[0063] S33: Based on a preset correlation threshold, performing alignment judgment on the dynamic statistical features.

[0064] Specifically, the two magnetic field signals after digital processing are time synchronized to ensure that the two signals are analyzed under the same time reference, for example, time synchronization is achieved by signal delay compensation, timestamp recording and synchronization algorithm. The time synchronization algorithm can adopt standard technologies such as Network Time Protocol (NTP) or Precision Time Protocol (PTP) to ensure high-precision time synchronization. During the calculation of dynamic statistical features, the dynamic statistical features of the two magnetic field signals are calculated based on the signal matching algorithm, wherein the dynamic statistical features include but are not limited to mean, variance, standard deviation, skewness and kurtosis. The algorithm for calculating dynamic statistical features can adopt time-frequency analysis technologies such as fast Fourier transform (FFT) and wavelet transform. When judging the alignment, the calculated dynamic statistical features are judged for alignment based on a preset correlation threshold. The alignment can be evaluated by calculating the similarity of the dynamic statistical features of the two signals. The higher the similarity, the better the alignment. The correlation threshold can be set according to actual application requirements. If the calculated correlation is higher than the preset threshold, the magnetic field signal alignment is determined to be successful; otherwise, the alignment is determined to have failed.

[0065] In order to improve the accuracy of alignment and feature matching, multi-dimensional dynamic statistical feature calculation can also be used in the implementation to increase the accuracy of alignment assessment; adaptive correlation threshold setting is adopted to adjust the threshold according to different electromagnetic environments and cable characteristics.

[0066] In some embodiments, S32, the step of calculating dynamic statistical features based on a signal matching algorithm, specifically includes:

[0067] Performing short-time Fourier transform on the two digitally processed magnetic field signals to obtain dynamic change characteristics;

[0068] Based on the preset frequency band, the time-frequency energy concentration is extracted and the dynamic statistical characteristics are calculated;

[0069] Based on the dynamic statistical characteristics, the autoregressive coefficient and the sample entropy are determined.

[0070] Specifically, the magnetic field signal to be analyzed is first digitized to convert the analog signal into a digital signal, which usually involves sampling and quantization. Sampling refers to sampling the signal at a certain time interval, and quantization refers to converting the continuous signal amplitude into a finite number of digital levels. The short-time Fourier transform (STFT) refers to the short-time Fourier transform of the digitized magnetic field signal to obtain the signal's spectral characteristics. The STFT uses a sliding window method to analyze the signal's spectrum at different time periods, thereby obtaining the signal's dynamic change characteristics.

[0071] According to the preset frequency band, the time-frequency energy concentration in the STFT result is calculated. The time-frequency energy concentration can reflect the intensity and speed of signal change within the frequency band. The calculation method can be to solve the spectrum energy within a specific time window, or use other energy-related statistical methods. Based on the extracted time-frequency energy concentration, the dynamic statistical features are calculated. Dynamic statistical features include mean, variance, kurtosis, etc., which are used to describe the dynamic change characteristics of the signal. Using the calculated dynamic statistical features, the autoregressive coefficient is determined through the autoregressive model. Among them, the autoregressive model is a statistical model that can be used to predict time series data, and the autoregressive coefficient reflects the temporal correlation of the signal. Finally, based on the dynamic statistical features, the sample entropy is calculated, wherein the sample entropy is an indicator to measure the complexity of the signal, which can reflect the randomness and uncertainty of the signal.

[0072] For example, given that the cable load current may change over time and contain random fluctuations, time-frequency analysis is introduced to extract joint features. Short-time Fourier transform is used to represent the signal in the time-frequency plane to capture the dynamic change characteristics of its spectrum over time. Features such as the time curve of the energy in a specific frequency band and the time-frequency energy concentration of the transient pulse signal are then extracted for matching. Dynamic statistical features (the distribution of the first-order difference or slope of the signal) are calculated to highlight subtle changes. Features such as autoregressive coefficients and sample entropy that reflect the signal morphology are superimposed. By combining multi-dimensional features (time domain + frequency domain + time-frequency), the characteristics of the magnetic field signal can be fully described, providing rich information support for subsequent matching algorithms.

[0073] In some embodiments, S33, the step of determining the alignment of the dynamic statistical features based on a preset correlation threshold, specifically includes:

[0074] Align the time axis of the signals collected at both ends;

[0075] Calculate the time delay and cross-correlation value of two signals through the cross-correlation function;

[0076] Finding a peak value and a maximum delay of the cross-correlation value based on the cross-correlation value;

[0077] Based on the maximum delay, compensating for the phase offset at both ends of the cable to determine an optimal alignment delay time difference;

[0078] If the correlation of the optimal alignment delay time difference is greater than or equal to a preset correlation threshold, it indicates that the alignment of the magnetic field signals is reliable.

[0079] Specifically, the magnetic field signals collected at both ends are first aligned on the time axis to ensure the temporal correspondence between the signals at both ends, so as to carry out subsequent correlation analysis. The cross-correlation function between the two signal segments is calculated. The cross-correlation function can be used to measure the similarity between the two signal segments. The time delay between the two signal segments can be determined by analyzing the peak value of the cross-correlation function. Based on the calculation result of the cross-correlation function, the peak value of the cross-correlation value and the corresponding peak position, that is, the maximum delay amount, are found. The corresponding peak position represents the time delay between the two signal segments. According to the maximum delay amount found, the phase offset at both ends of the cable is compensated to ensure the precise alignment of the signals in time, thereby obtaining the best alignment effect. Based on the compensation for the phase offset, the optimal alignment delay time difference is determined, and it is judged whether the correlation of the optimal alignment delay time difference is greater than or equal to the preset correlation threshold. If the correlation is greater than or equal to the preset threshold, it indicates that the alignment of the magnetic field signal is reliable.

[0080] For example, after signal processing and feature extraction, clear decision logic and alignment criteria need to be established to determine whether the signals at both ends match (i.e., originate from the same cable). Based on the fact that the signals at both ends are properly aligned, a feature metric is selected, and a reasonable threshold or scoring mechanism is set. To verify the effectiveness of the alignment, the signals collected at both ends are time-aligned. For example, the time delay of the two signals is estimated using a cross-correlation function: the cross-correlation values ​​at different delays are calculated, and the delay with the largest correlation peak is found. The signal at one end is then aligned with the signal at that offset. Phase offsets caused by clock differences or different startup times between the two devices are compensated for, and the optimal alignment delay Δt is determined. The robustness of the correlation around Δt is then checked. If the same signal pair maintains high correlation across several adjacent sampling delays, the alignment is reliable. Conversely, if the correlation extremes are very sensitive to delay variations, the signal correlation may be unstable.

[0081] In some embodiments, the step of calculating the time delay and the cross-correlation value of two signals using a cross-correlation function specifically includes:

[0082] Selecting a signal within a time window from the two magnetic field signals, and calculating the Pearson correlation coefficient r of the two magnetic field signals at the optimal alignment delay time difference;

[0083] If the Pearson correlation coefficient r is less than a preset correlation threshold, the alignment does not meet the requirements and the two cables are determined to belong to different cables.

[0084] Specifically, a time window of the same length is selected in the two magnetic field signals, and the signal within the time window will be used to calculate the Pearson correlation coefficient. The selection of the time window should ensure that the signal is of sufficient length to avoid the influence of noise, but not too long to reduce the amount of calculation. Within the selected time window, the Pearson correlation coefficient r of the two magnetic field signals is calculated under the optimal alignment delay time difference. The calculated Pearson correlation coefficient r is compared with the preset correlation threshold, which is a pre-set threshold used to determine whether the signal alignment meets the requirements. If the Pearson correlation coefficient r is less than the preset correlation threshold, it is considered that the alignment of the two magnetic field signals does not meet the requirements. In this case, it can be determined that the cables at both ends do not belong to the same cable. If the alignment does not meet the requirements, further signal processing measures can be taken, such as signal cleaning, resampling, or using other signal processing techniques to improve the signal quality.

[0085] It should be noted that the Pearson correlation coefficient is a statistic that measures the degree of linear correlation between two sets of data. Its value ranges from -1 to 1. A value close to 1 indicates a strong positive correlation, a value close to -1 indicates a strong negative correlation, and a value close to 0 indicates no correlation.

[0086] For example, the normalized cross-correlation coefficient is used as a matching metric, with an empirical threshold set. The Pearson correlation coefficient r is calculated for the optimal alignment of the two signals, with a value range of [-1, 1]. A judgment threshold is set in advance. If r is above the threshold, the two waveforms are highly similar and can be determined to be from the same cable; conversely, if the correlation coefficient is low, they are considered mismatched. To ensure that normalized cross-correlation eliminates the influence of amplitude factors and only reflects the consistency of waveform shape, the maximum cross-correlation value is calculated by randomly selecting signals within a time window and comparing it with the threshold to make a judgment.

[0087] In some embodiments, the step of S2, sequentially amplifying, filtering, and digitizing the magnetic field signals at both ends of the cable, and transmitting the signals to a data aligner, specifically includes:

[0088] Acquiring a magnetic field signal around the cable and performing pre-gain amplification to suppress common-mode noise and DC drift;

[0089] Filtering and digitally processing the magnetic field signal after the pre-gain amplification to convert the continuous magnetic field signal into a discrete time series, wherein the filtering frequency of the digital processing is less than or equal to half of the sampling frequency;

[0090] Performing gain calibration and zero point calibration on the discrete time series after digitization.

[0091] Specifically, magnetic field signals around the cable are acquired through devices such as magnetic field sensors. These magnetic field signals contain useful information about the cable's status. Pre-amplification is performed on the received magnetic field signals to increase signal strength, thereby suppressing common-mode noise and DC drift that could interfere with accurate signal analysis.

[0092] The amplified magnetic field signal is filtered to remove high-frequency noise and interference. The filter should be selected to ensure that the filtering frequency is less than or equal to half the sampling frequency to avoid aliasing. The filtered magnetic field signal is digitized to convert the continuous magnetic field signal into a discrete time series. The steps of digital processing include sampling and quantization, where sampling refers to sampling the signal within a certain time interval, and quantization refers to converting the continuous signal amplitude into a finite digital level. The discrete time series after digitization is gain calibrated. The purpose of gain calibration is to ensure that the amplitude of the signal is accurate for subsequent processing and analysis. The discrete time series after gain calibration is zero-point calibrated. The purpose of zero-point calibration is to eliminate the DC offset in the signal and ensure that the starting point of the signal is at zero level. The magnetic field signal after signal amplification, filtering and digitization is transmitted to the data aligner.

[0093] For example, during low-noise preamplification, a highly sensitive magnetic field sensor (such as a Hall effect sensor or induction coil) is used to detect minute changes in the magnetic field around the cable, and a high-gain-bandwidth, low-noise op amp is used as a preamplifier for preamplification. A differential amplifier architecture is employed to suppress common-mode noise and DC drift, offsetting common-mode interference at both inputs and ensuring low noise and distortion for the target signal when it enters the relevant processing channels.

[0094] During the bandpass filtering and anti-aliasing process, the amplified signal is fed into a bandpass filter circuit to remove irrelevant frequencies, such as the ambient power frequency, and high-frequency interference noise, thereby improving the signal-to-noise ratio. The bandpass filter is designed with an appropriate center frequency and bandwidth to cover the primary frequency components of the cable current signal (temporarily set to the 50Hz fundamental and its variations) while rejecting DC offset and RF noise. Before analog-to-digital conversion, an anti-aliasing low-pass filter is connected in series to limit the signal spectrum to below half the sampling frequency of the high-resolution, high-speed analog-to-digital converter (ADC) to prevent high-frequency components from aliasing into the baseband. The anti-aliasing filter must have a steep roll-off characteristic and sufficient stopband attenuation, while also not introducing excessive noise or amplitude-frequency distortion.

[0095] During analog-to-digital conversion and digital preprocessing, an ADC is used to digitize the analog signal, converting the continuous magnetic field waveform into a discrete time series. The ADC bit width should be large enough to resolve subtle signal changes, and the sampling rate should be at least twice the highest signal frequency (150 Hz in this example) to preserve waveform details. Oversampling can be used to increase effective resolution if necessary. The data collected by the ADC serves as the basis for subsequent digital signal processing. Gain and zero calibration are also performed on the sensor and amplifier channels to ensure comparability of the digital signals obtained by both devices.

[0096] In some embodiments, S1, before installing magnetic field signal detectors at both ends of the cable and obtaining magnetic field signals at both ends of the cable, the cable pairing method based on magnetic field signal detection further includes:

[0097] Select a shielding cover that matches the diameter of the cable and fix the shielding cover tightly against the surface of the cable.

[0098] Specifically, a shielding cover that matches the cable's diameter and characteristics should be selected. The material and dimensions of the shielding cover should effectively capture and concentrate magnetic field signals while reducing external interference. The shielding cover can be made of metal such as copper, aluminum, or other conductive materials to ensure good electromagnetic compatibility.

[0099] Place the selected shielding cover close to the surface of the cable, ensuring there is no gap or air gap between the shielding cover and the cable, and use screws, clamps or other fixing devices to firmly fix the shielding cover to the cable to prevent the shielding cover from falling off or shifting during operation.

[0100] It should be noted that when installing a shield, the shape and position of the shield should match the shape and direction of the cable to maximize the capture of magnetic field signals. The detector should be installed in a position that ensures that it can effectively detect the magnetic field signal captured by the shield. The distance between the detector and the shield should be appropriate to ensure signal accuracy and stability.

[0101] For example, the implementation of a magnetic field signal detector includes: selecting a shielding cover suitable for the cable diameter and fixing it close to the cable surface; starting the magnetic field signal detector to detect the magnetic field signal inside the cable; converting the magnetic field signal into an electrical signal through a signal amplification and filtering circuit; and transmitting the detection data to a data aligner through a wireless communication module.

[0102] By selecting and fixing a shielding cover that matches the cable diameter, the detection efficiency and accuracy of the magnetic field signal are improved, external interference is reduced, and the accuracy and reliability of cable pairing are improved.

[0103] It should be noted that, given the potential for uncertainty in a single comparison due to noise and incidental events, the cable pairing method employs multiple comparisons and false positive handling mechanisms to enhance reliability. For example, multiple sampling, fault tolerance, and hysteresis are employed to reduce false positives and false negatives. The continuously acquired magnetic field signal is divided into multiple time slices, with feature comparisons performed every few seconds. The matching decision logic described above is independently applied to each window, resulting in a series of results or match scores. Statistics are compiled across multiple window results to enhance confidence in the overall decision.

[0104] A dual threshold and hysteresis mechanism is implemented in the decision logic to reduce jitter in edge cases. A higher confirmation threshold and a slightly lower maintenance threshold are defined: when the match score exceeds the higher threshold, the match is considered successful; however, if the score subsequently drops slightly but remains above the lower threshold, the previous success status is maintained and not immediately flipped to failure. Hysteresis is applied using the same logic to prevent frequent indicator light changes in critical situations. Furthermore, for situations where a match is initially deemed mismatched but close to the threshold, a fault-tolerant retry is allowed: when the correlation coefficient is slightly below the decision threshold, the match is not immediately considered a failure. Instead, the observation time is extended or the threshold is lowered before retrying to prevent missing a true match.

[0105] The cable pairing method utilizes a red / green indicator light output drive mechanism. For example, the matching algorithm provides intuitive feedback to the user on the success or failure of cable pairing through a simple, clear red / green / yellow indicator module. After the matching result is verified, it is converted into a logic signal output. Successful match = TRUE, unsuccessful match = FALSE. The digital output directly drives the LED control circuit: a green indicator lights up when the output is TRUE, and a red indicator lights up when the output is FALSE. If the signal amplitude falls below the detection threshold and reliable features cannot be extracted, the indicator lights up yellow to indicate an abnormality.

[0106] In terms of safety and reset in the cable pairing method, the red light is on during power-on initialization (indicating no match), and only turns green when the algorithm clearly detects a successful match, preventing the green light from being mistakenly lit and causing safety hazards.

[0107] The present application also provides a cable pairing system based on magnetic field signal detection, the cable pairing system based on magnetic field signal detection comprising:

[0108] A magnetic field signal detector, used to obtain a magnetic field signal at the end of the cable;

[0109] A signal processing component, configured to sequentially amplify, filter, and digitize the magnetic field signal;

[0110] a data aligner, configured to perform time synchronization and feature matching on the magnetic field signal;

[0111] The communication module is used to transmit the digitally processed magnetic field signal to the data aligner.

[0112] Specifically, a magnetic field signal detector is installed at the end of the cable. The magnetic field signal detector can be a Hall effect sensor, a magnetoresistive sensor, or other sensor that can detect changes in the magnetic field. The magnetic field signal detector has high sensitivity so that it can accurately capture the weak magnetic field signal generated by the current flowing in the cable. The signal processing component includes a signal amplifier and a filter. The signal amplifier is used to increase the amplitude of the magnetic field signal so that it can be processed by the subsequent filter. The filter is used to remove noise and unnecessary frequency components in the signal, such as a low-pass filter, a band-pass filter, and a notch filter. The data aligner includes a time synchronization unit and a feature matching unit. The time synchronization unit is used to synchronize the magnetic field signals detected at different cable ends in time, which is achieved by signal delay compensation or timestamp recording. The feature matching unit is used to extract and match the features of the synchronized magnetic field signals. Feature extraction and matching can be achieved through various pattern recognition algorithms, such as correlation analysis, wavelet transform, or machine learning methods. The communication module can use wired or wireless communication methods, such as Ethernet, Wi-Fi, Bluetooth or LoRa. It should be noted that the communication module needs to have sufficient bandwidth and low latency to ensure real-time data transmission. It should also have a certain anti-interference ability to ensure the stability of signal transmission in complex electromagnetic environments.

[0113] By using a magnetic field signal detector to acquire the magnetic field signal at the cable end and using the signal processing component for amplification, filtering, and digitization, the accuracy of cable pairing can be effectively improved. The data aligner synchronizes the time and matches the characteristics of the signals, ensuring the synchronization and similarity of the two signals, thereby improving pairing accuracy. The collaborative operation of the magnetic field signal detector, signal processing component, data aligner, and communication module improves the accuracy, efficiency, and reliability of cable pairing.

[0114] In some embodiments, the magnetic field signal detector is annular in shape, and a plurality of magnetic field sensors are disposed inside the magnetic field signal detector.

[0115] Specifically, a plurality of magnetic field sensors are provided in the magnetic field signal detector. The plurality of magnetic field sensors are arranged in a ring shape. The magnetic field sensors are high-sensitivity magnetic field sensors, for example, the magnetic field sensors are TMR or fluxgate sensors.

[0116] The above are merely specific embodiments of the present application to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but rather is intended to conform to the widest scope consistent with the principles and novel features of the present application.

Claims

1. A cable pairing method based on magnetic field signal detection, characterized in that: include: S1. Installing magnetic field signal detectors at both ends of the cable to obtain magnetic field signals at both ends of the cable; S2, sequentially amplifying, filtering, and digitizing the magnetic field signals at both ends of the cable, and transmitting the signals to a data aligner; S3. Based on the data aligner, performing time synchronization and feature matching on the two digitized magnetic field signals; S4. If the two magnetic field signal features match successfully, it indicates that the magnetic field signals are aligned, and it is determined that the cables are paired successfully, and a matching result is output.

2. The cable pairing method based on magnetic field signal detection according to claim 1, characterized in that: S3, based on the data aligner, performing time synchronization and feature matching on the two digitized magnetic field signals, specifically comprising: S31, performing time synchronization on the two digitally processed magnetic field signals; S32, calculating dynamic statistical features based on a signal matching algorithm; S33: Based on a preset correlation threshold, performing alignment judgment on the dynamic statistical features.

3. The cable pairing method based on magnetic field signal detection according to claim 2, characterized in that: S32, the step of calculating dynamic statistical features based on the signal matching algorithm, specifically comprising: Performing short-time Fourier transform on the two digitally processed magnetic field signals to obtain dynamic change characteristics; Based on the preset frequency band, the time-frequency energy concentration is extracted and the dynamic statistical characteristics are calculated; Based on the dynamic statistical characteristics, the autoregressive coefficient and the sample entropy are determined.

4. The cable pairing method based on magnetic field signal detection according to claim 2, characterized in that: S33, based on a preset correlation threshold, the step of determining the alignment of the dynamic statistical features, specifically comprising: Align the time axis of the signals collected at both ends; Calculate the time delay and cross-correlation value of two signals through the cross-correlation function; Finding a peak value and a maximum delay of the cross-correlation value based on the cross-correlation value; Based on the maximum delay, compensating for the phase offset at both ends of the cable to determine an optimal alignment delay time difference; If the correlation of the optimal alignment delay time difference is greater than or equal to a preset correlation threshold, it indicates that the alignment of the magnetic field signals is reliable.

5. The cable pairing method based on magnetic field signal detection according to claim 4, characterized in that: The step of calculating the time delay and the cross-correlation value of two signals by using the cross-correlation function specifically includes: Selecting a signal within a time window from the two magnetic field signals, and calculating the Pearson correlation coefficient r of the two magnetic field signals at the optimal alignment delay time difference; If the Pearson correlation coefficient r is less than a preset correlation threshold, the alignment does not meet the requirements and the two cables are determined to belong to different cables.

6. The cable pairing method based on magnetic field signal detection according to claim 1, characterized in that: S2, amplifying, filtering, and digitizing the magnetic field signals at both ends of the cable in sequence, and transmitting the signals to a data aligner, specifically comprising: Acquiring a magnetic field signal around the cable and performing pre-gain amplification to suppress common-mode noise and DC drift; Filtering and digitally processing the magnetic field signal after the pre-gain amplification to convert the continuous magnetic field signal into a discrete time series, wherein the filtering frequency of the digital processing is less than or equal to half of the sampling frequency; Performing gain calibration and zero point calibration on the discrete time series after digitization.

7. The cable pairing method based on magnetic field signal detection according to claim 1, characterized in that: The magnetic field signal detector and the data aligner perform data transmission via wireless communication.

8. The cable pairing method based on magnetic field signal detection according to claim 1, characterized in that: S1. Before installing magnetic field signal detectors at both ends of the cable and obtaining magnetic field signals at both ends of the cable, the cable pairing method based on magnetic field signal detection further includes: Select a shielding cover that matches the diameter of the cable and fix the shielding cover tightly against the surface of the cable.

9. A cable pairing system based on magnetic field signal detection, characterized in that: The cable pairing system based on magnetic field signal detection includes: A magnetic field signal detector, used to obtain a magnetic field signal at the end of the cable; A signal processing component, configured to sequentially amplify, filter, and digitize the magnetic field signal; a data aligner, configured to perform time synchronization and feature matching on the magnetic field signal; The communication module is used to transmit the digitally processed magnetic field signal to the data aligner.

10. The cable pairing system based on magnetic field signal detection according to claim 9, characterized in that: The magnetic field signal detector is annular in shape and is provided with a plurality of magnetic field sensors.

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