Intelligent network line live detection fault device and signal processing system

Abstract

The application relates to the technical field of power maintenance tools, and discloses a device for detecting faults of intelligent network lines under electricity and a signal processing system, wherein the device comprises an electromagnetic induction probe, the electromagnetic induction probe comprises a magnetic conductive shell and a magnetic field inductor; the magnetic conductive shell is provided with an opening, the opening is used for being close to and facing the line to be detected; the magnetic field inductor is arranged in the magnetic conductive shell; the sensing surface of the magnetic field inductor is arranged to face the opening; the magnetic conductive shell is used for forming a low-magnetic-resistance cavity through the high-magnetic-conductivity characteristic of the magnetic conductive shell, guiding the fault magnetic field signal of the line to be detected to flow into the magnetic conductive shell through the opening, concentrating on the magnetic field inductor, and guiding the interference magnetic field signal far away from the opening to the outer wall of the magnetic conductive shell, so that the interference magnetic field signal is prevented from entering the magnetic conductive shell. According to the embodiment, the fault magnetic field signal reaching the magnetic field inductor is enhanced, the detection capability and the detection sensitivity of the line fault magnetic field signal are improved, and efficient detection of the line under the electricity is realized.

Description

Technical Field

[0001] This invention relates to the field of power maintenance tools, and in particular to an intelligent network line live fault detection device and signal processing system. Background Technology

[0002] With the deep integration of digital technologies such as big data and artificial intelligence into the power grid, line parameter testing devices are increasingly being applied to scenarios such as line inspection, line construction, high-altitude operations, and on-site emergency repairs. However, due to the special characteristics of overhead lines, a smart, efficient, and safe live-line fault detection device has not yet been developed on the market. Line faults cannot be detected when the line is energized. If a fault cannot be detected in a timely manner while the line is energized, it can lead to risks such as large-scale power outages for users in the affected area when the fault point is severely grounded. Summary of the Invention

[0003] This invention provides an intelligent network line live fault detection device and signal processing system to solve the problem of detecting whether a line has a fault while it is energized.

[0004] The present invention provides an intelligent network line live fault detection device, which includes an electromagnetic induction probe, wherein the electromagnetic induction probe includes a magnetic housing and a magnetic field sensor;

[0005] The magnetic housing has an opening for approaching and facing the circuit under test; the magnetic field sensor is disposed inside the magnetic housing; the sensing surface of the magnetic field sensor faces the opening.

[0006] The magnetically conductive housing is used to form a low magnetic reluctance cavity through its high magnetic permeability characteristics, guiding the fault magnetic field signal of the circuit under test to flow through the opening into the magnetically conductive housing and concentrate it onto the magnetic field sensor. At the same time, it is used to guide the interference magnetic field signal away from the opening to the outer wall of the magnetically conductive housing, preventing the interference magnetic field signal from entering the magnetically conductive housing.

[0007] Furthermore, the sensing surface of the magnetic field sensor is parallel to the plane of the opening. A differential dual-antenna structure is also provided inside the magnetic housing. The differential dual-antenna structure includes a first antenna, a second antenna, and a processor. Both the first antenna and the second antenna are used to measure the amplitude and phase of the fault magnetic field signal. The first antenna and the second antenna are distributed on both sides of the magnetic field sensor along the line connecting the opening and the magnetic field sensor. The first antenna is located on the side of the magnetic field sensor closer to the opening, and the second antenna is located on the side of the magnetic field sensor away from the opening. The first antenna is connected to the second antenna through the processor. The processor is used to determine whether the direction of the fault magnetic field signal is perpendicular to the sensing surface of the magnetic field sensor by comparing whether the phase and amplitude of the first antenna and the second antenna are consistent.

[0008] Furthermore, a first magnetic field shielding layer is provided on the side of the second antenna near the magnetic field sensor.

[0009] Further, the first antenna includes a first magnetic induction coil and a second magnetic induction coil, the second antenna includes a third magnetic induction coil and a fourth magnetic induction coil, and the processor includes a first calculator, a second calculator, and a comparator. The first magnetic induction coil and the third magnetic induction coil are correspondingly arranged, the second magnetic induction coil and the fourth magnetic induction coil are correspondingly arranged, the first calculator is arranged between the first magnetic induction coil and the third magnetic induction coil, and the second calculator is arranged between the second magnetic induction coil and the fourth magnetic induction coil. The first calculator is connected to the second calculator through the comparator. The first calculator is used to calculate a first phase difference and a first amplitude difference, and the second calculator is used to calculate a second phase difference and a second amplitude difference. The comparator is used to determine whether the direction of the fault magnetic field signal is perpendicular to the sensing surface of the magnetic field sensor by judging whether the first amplitude difference and the second amplitude difference and the first phase difference and the second phase difference are consistent.

[0010] Furthermore, a second magnetic field shielding layer is provided on the side of the first antenna closest to the magnetic field sensor.

[0011] Furthermore, an electric field shielding layer is provided on the outer or inner side of the magnetic housing. The electric field shielding layer is used to prevent the electric field outside the magnetic housing from interfering with the measurement of the fault magnetic field signal by the magnetic field sensor.

[0012] Furthermore, the magnetically conductive housing is made of permalloy material.

[0013] Furthermore, it also includes a phase matching instrument, which includes a signal acquisition head, a telescopic rod, a handle, a signal receiver, and a signal transmitter. The signal acquisition head is made of insulating material. The telescopic rod, handle, signal receiver, and signal transmitter are all equipped with insulating shells. The signal acquisition head is connected to one end of the telescopic rod for acquiring the phase signal of the circuit under test. The other end of the telescopic rod is connected to the handle. The signal receiver is located near the signal acquisition head for collecting the phase signal. The signal transmitter is located near the handle and is electrically connected to the signal receiver. The signal transmitter is used to send the phase signal to a remote monitoring center.

[0014] The present invention also provides a signal processing system for processing magnetic field signals collected by the intelligent network line live fault detection device described in any of the above claims, including a signal processing component, wherein the signal output terminals of the magnetic field sensor and the differential dual antenna structure are both connected to the signal processing component, and the signal processing component includes a signal conditioning circuit, an analog-to-digital converter and a microprocessor unit.

[0015] The input terminal of the signal conditioning circuit is connected to the signal output terminal of the magnetic field sensor and the differential dual antenna structure, respectively. The output terminal of the signal conditioning circuit is connected to the input terminal of the analog-to-digital converter, and the output terminal of the analog-to-digital converter is connected to the input terminal of the microprocessor unit.

[0016] The signal conditioning circuit is used to receive the original signal and perform filtering, amplification and gain processing. The analog-to-digital converter is used to convert the conditioned analog signal into a digital signal. The microprocessor unit is used to determine whether there is a fault in the line based on the digital signal.

[0017] As can be seen from the above technical solutions, the present invention has the following advantages:

[0018] In this embodiment, the magnetically conductive housing, based on its high permeability, forms a low magnetic reluctance cavity that attracts fault magnetic field signals to flow into the housing. This effectively concentrates the line magnetic field above the opening to the magnetic field sensor inside the housing, thereby enhancing the line fault magnetic field signal reaching the sensor and improving the detection capability and sensitivity. Simultaneously, by guiding interfering magnetic field signals away from the opening to the outer wall of the housing, interference signals are prevented from entering the housing, further optimizing the detection accuracy of the magnetic field sensor for fault magnetic field signals of energized lines and ensuring efficient detection of lines under energized conditions. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the electromagnetic induction probe in an intelligent network line live fault detection device provided in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the operation of an electromagnetic induction probe in an intelligent network line live fault detection device provided in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the phase gauging instrument in an intelligent network line live fault detection device provided in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of a signal processing system structure provided in an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram showing the positions of the first and second magnetic field shielding layers of the electromagnetic induction probe in an intelligent network line live fault detection device provided in an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures:

[0026] 1. Electromagnetic induction probe; 11. Fault magnetic field signal; 12. Magnetic housing; 13. Magnetic field sensor; 14. Opening; 15. First antenna; 16. Second antenna; 17. Electric field shielding layer; 2. High-voltage substation; 31. Signal acquisition head; 32. Telescopic pole; 33. Handle; 34. Signal receiver; 35. Signal transmitter; 36. Button; 4. Circuit under test; 5. First magnetic field shielding layer; 6. Second magnetic field shielding layer. Detailed Implementation

[0027] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0028] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the present application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] This invention provides an intelligent network line live fault detection device, including an electromagnetic induction probe 1. Please refer to [link / reference]. Figures 1-2 The electromagnetic induction probe 1 includes a magnetic housing 12 and a magnetic field sensor 13;

[0030] The magnetic housing 12 is provided with an opening 14, which is used to approach and face the circuit 4 under test; the magnetic field sensor 13 is disposed inside the magnetic housing 12; the sensing surface of the magnetic field sensor 13 faces the opening 14.

[0031] The magnetic housing 12 is used to form a low magnetic resistance cavity through its high magnetic permeability characteristics to guide the fault magnetic field signal 11 of the circuit under test to flow through the opening 14 into the magnetic housing 12 and concentrate it onto the magnetic field sensor 13. At the same time, it is used to guide the interference magnetic field signal away from the opening 14 to the outer wall of the magnetic housing 12, so as to prevent the interference magnetic field signal from entering the magnetic housing 12.

[0032] It is understandable that the current in a circuit generates a magnetic field around it based on the principle of electromagnetic induction, and the strength and direction of the magnetic field are directly related to the magnitude and direction of the current. When a circuit malfunctions, such as a short circuit causing a sudden increase in current, an open circuit causing current interruption, or poor contact causing current instability, these abnormal changes in current will directly cause corresponding abnormal changes in the surrounding magnetic field—the magnetic field strength increases significantly during a short circuit, disappears during an open circuit, and exhibits irregular fluctuations in the magnetic field during poor contact. Based on this, by capturing these abnormal changes in the magnetic field through the magnetic field sensor 13, it is possible to infer whether there is a fault in the circuit. This method utilizes the logic chain of "abnormal current → abnormal magnetic field → fault detection," achieving effective detection of circuit faults and offering advantages such as being non-contact and not affecting circuit operation. However, since overhead lines are mostly distributed outdoors, they face numerous sources of electromagnetic interference: nearby high-voltage substations 2 and communication base stations generate continuous electromagnetic noise; lightning electromagnetic pulses during thunderstorms, alternating magnetic fields from wind turbines, and even radiation from ground vehicle motors can all create chaotic magnetic field signals, affecting the detection of fault magnetic field signals 11. In high-voltage overhead transmission systems, the relative height of the overhead test line 4 to the ground is much greater than the distance between the lines, causing the three-phase signals of the fault magnetic field signal 11 to alias and become weak when it propagates to the electromagnetic induction probe 1. This signal is highly susceptible to interference from surrounding environmental factors, leading to instability in the fault magnetic field signal 11. Therefore, improving the directivity and anti-interference capability of the measurement is particularly challenging.

[0033] It should be noted that the line under test in this embodiment is an overhead line, including a three-phase transmission line. Under normal operating conditions, the three-phase currents are symmetrically distributed, and the alternating magnetic fields generated by each phase are vector-superimposed in space due to a 120° phase difference. According to the principle of electromagnetic induction and the law of magnetic field superposition, the magnetic fields generated by the symmetrical three-phase currents cancel each other out macroscopically, making the combined magnetic field strength around the line approach zero. At this time, the electromagnetic induction probe placed below the line cannot detect a significant magnetic field signal from the line. When an asymmetrical fault occurs in the line (such as the voltage of one phase abnormally dropping to 5V while the other two phases maintain the rated voltage of 220V), the symmetry of the three-phase currents is disrupted, and the relationship between the current amplitude and phase becomes unbalanced, causing the vector superposition effect of the magnetic fields of each phase to fail, and a detectable fault magnetic field signal 11 is formed around the line.

[0034] In specific implementation, the magnetically conductive housing 12 of this embodiment forms a low magnetic reluctance cavity based on its high magnetic permeability, attracting the fault magnetic field signal 11 to flow into the magnetically conductive housing 12. The high magnetic permeability means that the magnetic permeability of the magnetically conductive housing 12 is much higher than that of the surrounding environment, such as air or other non-magnetic materials, which can more effectively gather and guide the magnetic field lines. The fault magnetic field signal 11 of the circuit diffuses in space. When it encounters the magnetically conductive housing 12, since the magnetic permeability of the material of the magnetically conductive housing 12 is much higher than that of air, the magnetic field lines will approach the magnetically conductive housing 12. The fault magnetic field signal 11 above the opening 14 overcomes the high magnetic reluctance air and enters the low magnetic reluctance cavity, while the interference magnetic field signal located on the outside of the opening 14 is guided to the outer wall of the magnetically conductive housing 12 and cannot pass through the magnetically conductive housing 12 to enter the low magnetic reluctance cavity. Therefore, the magnetically conductive housing 12 of this embodiment can form a low magnetic reluctance cavity based on its high magnetic permeability characteristics, effectively concentrating the magnetic field of the line above the opening 14 to the magnetic field sensor 13 inside the magnetically conductive housing 12, thereby enhancing the fault magnetic field signal 11 of the line reaching the magnetic field sensor 13, improving the detection capability and sensitivity of the fault magnetic field signal 11 of the conductor, and at the same time guiding the interfering magnetic field signal away from the opening 14 to the outer wall of the magnetically conductive housing 12, avoiding the interfering magnetic field signal from entering the magnetically conductive housing 12, further optimizing the detection accuracy of the magnetic field sensor 13 for the fault magnetic field signal 11 of the energized line, and ensuring efficient detection of the fault magnetic field signal 11 of the line in the energized state.

[0035] In a more specific embodiment, the magnetic housing 12 is made of permalloy, a nickel-iron alloy (typically composed of 78% nickel and 22% iron), whose most significant characteristic is that its magnetic permeability (μ) is much higher than that of ordinary ferromagnetic materials (such as iron and steel), and can even reach tens of thousands to hundreds of thousands of times the magnetic permeability of air.

[0036] It should be noted that the permalloy-coated magnetic housing 12, with its extremely high permeability, provides a path with extremely low magnetic reluctance. This attracts and guides the fault magnetic field signal 11 above the opening 14 of the magnetic housing 12 into the housing 12. For the interfering magnetic field to enter the interior of the housing 12, it must pass through the wall of the housing 12 (from external air → housing → internal air). The total magnetic reluctance of this path is much higher than that propagating along the outer wall of the housing 12. Therefore, the interfering magnetic field is guided to the outer wall of the housing 12 and travels along the surface, unable to enter the interior of the housing, thus achieving shielding of the interfering magnetic field signal.

[0037] In a more specific embodiment, the magnetic field sensor 13 employs a Hall sensor.

[0038] It should be noted that, as Figure 2As shown, in this embodiment, the electromagnetic induction probe 1 is placed near and below the live line during use. The electromagnetic induction probe 1 is far from interference signal sources such as the high-voltage substation 2, while the live line is even closer to the electromagnetic induction probe 1. The opening 14 of the magnetic housing 12 is close to and faces the line under test. At this time, the fault magnetic field signal 11 generated by the live line is stronger than the interference signal at and above the opening 14 of the magnetic housing 12 of the electromagnetic induction probe 1. Furthermore, the fault magnetic field signal 11 is mainly concentrated above the opening 14 of the magnetic housing 12, while the interference signal is distributed around the magnetic housing 12. Therefore, the interference signal distributed around the magnetic housing 12 will propagate along the outer wall of the magnetic housing 12, which has lower magnetic resistance, and will not enter the magnetic housing 12. The strong fault magnetic field signal 11 overcomes the air resistance near the opening 14 of the magnetic housing 12 under the low magnetic resistance of the entire magnetic housing 12 and directly enters the magnetic housing 12 to reach the Hall sensor for measurement. It does not need to go through the path (from the outside air → housing → inside air). If the low magnetic resistance attraction of the magnetic housing 12 is not set, most of the fault magnetic field signal 11 will be unable to overcome the high magnetic resistance of the air between the Hall sensor and the live circuit to reach the surface of the Hall sensor. There is also an interference signal above the opening 14 of the magnetic housing 12. After shielding the interference signals around it, the interference signal that enters from above the opening 14 with the fault magnetic field signal 11 is very weak and will not affect the normal test data. At the same time, a very small part of the strong fault magnetic field signal 11 is guided to the magnetic housing and will not affect the normal test data.

[0039] Compared with existing technologies CN120294393A and CN118425599A, this embodiment has a different application scenario. The object to be detected in this embodiment is an elevated live line. In this embodiment, the electromagnetic induction probe 1 is placed below the elevated live line during use and does not come into contact with the live line. When there is a fault in the live line, the generated fault magnetic field signal 11 overcomes the high magnetic resistance of the air near the opening 14 and gathers inside the magnetic housing 12 under the low magnetic resistance of the magnetic housing 12 with the opening 14. The opening 14 is provided to the magnetic housing 12 to allow the stronger fault magnetic field signal above the opening 14 to enter the magnetic housing 12, while shielding the fault magnetic field signal 11 located around the magnetic housing 12 outside the magnetic housing 12. In this embodiment, both the fault magnetic field signal 11 and the interference signal come from the magnetic housing 12. Therefore, only by providing the opening 14 can the fault magnetic field located above the opening 14 enter the magnetic housing 12 and reach the Hall sensor.

[0040] Please see Figure 1In a more specific embodiment, the sensing surface of the magnetic field sensor 13 is parallel to the plane of the opening 14. A differential dual-antenna structure is also provided inside the magnetic housing 12. The differential dual-antenna structure includes a first antenna 15, a second antenna 16, and a processor. Both the first antenna 15 and the second antenna 16 are used to measure the amplitude and phase of the fault magnetic field signal 11. The first antenna 15 and the second antenna 16 are distributed on both sides of the magnetic field sensor 13 along the line connecting the opening 14 and the magnetic field sensor 13. The first antenna 15 is located on the side of the magnetic field sensor 13 closer to the opening 14, and the second antenna 16 is located on the side of the magnetic field sensor 13 away from the opening 14. The first antenna 15 is connected to the second antenna 16 through the processor. The processor is used to determine whether the direction of the fault magnetic field signal 11 is perpendicular to the sensing surface of the magnetic field sensor 13 by comparing whether the phases of the first antenna 15 and the second antenna 16 are consistent and whether the amplitudes of the first antenna 15 and the second antenna 16 are also consistent.

[0041] Understandably, in practical implementation, the air path perpendicularly through opening 14 is the shortest, minimizing magnetoresistive loss and retaining the most magnetic field lines. Therefore, the magnetic field strength entering the magnetic housing 12 perpendicularly to opening 14 is the greatest. Hall effect sensors and other magnetic field sensors 13 typically only determine magnetic field strength, not direction. If the measured magnetic field is not perpendicular to the sensing surface of the Hall effect sensor and opening 14, the device's detection of the conductor's magnetic field may be affected by external interference magnetic field signals. Therefore, it is necessary to determine the magnetic field direction to ensure that the magnetic field signal sensed by the magnetic field sensor 13 originates from the fault magnetic field signal 11 entering the magnetic housing 12 perpendicularly from opening 14. Figure 1 As shown, in this embodiment, the amplitude and phase of the fault magnetic field signal 11 are measured by the first antenna 15 and the second antenna 16 located on both sides of the magnetic field sensor 13. Under normal circumstances, when no interfering magnetic field signal enters the magnetic housing 12, both the first antenna 15 and the second antenna 16 can detect the fault magnetic field signal 11. When the amplitude and phase measured by the first antenna 15 are consistent with those of the second antenna 16, it can be confirmed that the fault magnetic field signal 11 is perpendicular to the sensing surface of the magnetic field sensor 13, eliminating the possibility of interfering magnetic field signals from other directions entering the magnetic housing 12, solving the problem of the directional resolution of the fault magnetic field signal 11, and thus effectively improving the detection accuracy of the electromagnetic induction probe 1.

[0042] Please see Figure 5 In a more specific embodiment, a first magnetic field shielding layer 5 is provided on the side of the second antenna 16 near the magnetic field sensor 13.

[0043] Please see Figure 5 In a more specific embodiment, a second magnetic field shielding layer 6 is provided on the side of the first antenna 15 near the magnetic field sensor 13.

[0044] It should be noted that the interference signal approaches the magnetic housing 12 from all sides and weakens on the magnetic housing 12. When the interference signal strength is large, it will enter the magnetic housing 12 from the outer wall along the opening and be detected by the first antenna 15, the second antenna 16 and the magnetic field sensor 13 inside the magnetic housing 12. Since the magnetic housing 12 is located far from the interference signal source (such as a high-voltage substation), although the interference signal strength is enhanced, it is always weaker than the fault magnetic field signal 11. Even if the interference signal enters the magnetic housing 12 and is detected by the first antenna 15, the second antenna 16 and the magnetic field sensor 13, it will not affect the acquisition of the test value of the fault magnetic field signal 11.

[0045] like Figure 5 As shown, since this embodiment is equipped with a first magnetic field shielding layer 5 and a second magnetic field shielding layer 6, the first magnetic field shielding layer 5 and the second magnetic field shielding layer 6 have a shielding effect. The fault magnetic field signal 11 is stronger than the interference signal. After the fault magnetic field signal 11 and the interference signal pass through the first magnetic field shielding layer 5 and the second magnetic field shielding layer 6, they are synchronously attenuated. The intensity difference between the fault magnetic field signal 11 and the interference signal is relatively preserved. This makes the proportion of the fault magnetic field signal 11 larger and the proportion of the interference signal smaller in the magnetic field signals detected by the first antenna 15, the second antenna 16 and the magnetic field sensor 13. This makes it easier to determine whether the circuit under test has a fault magnetic field signal 11.

[0046] Please see Figure 5 In a more specific embodiment, the first antenna 15 includes a first magnetic induction coil and a second magnetic induction coil, the second antenna 16 includes a third magnetic induction coil and a fourth magnetic induction coil, and the processor includes a first calculator, a second calculator, and a comparator. The first magnetic induction coil and the third magnetic induction coil are correspondingly arranged, the second magnetic induction coil and the fourth magnetic induction coil are correspondingly arranged, the first calculator is arranged between the first magnetic induction coil and the third magnetic induction coil, and the second calculator is arranged between the second magnetic induction coil and the fourth magnetic induction coil. The first calculator is connected to the second calculator through the comparator. The first calculator is used to calculate a first phase difference and a first amplitude difference, the second calculator is used to calculate a second phase difference and a second amplitude difference, and the comparator is used to determine whether the direction of the fault magnetic field signal 11 is perpendicular to the sensing surface of the magnetic field sensor 13 by judging whether the first amplitude difference and the second amplitude difference and the first phase difference and the second phase difference are consistent.

[0047] Understandably, in specific implementation, amplitude refers to the number of magnetic field lines incident on the magnetic induction coil, phase refers to the angle at which the magnetic field lines incident on the magnetic induction coil, the first amplitude difference refers to the difference between the amplitude of the first magnetic induction coil and the amplitude of the third magnetic induction coil, the second amplitude difference refers to the difference between the amplitude of the second magnetic induction coil and the amplitude of the fourth magnetic induction coil, the first phase difference is the difference between the phase of the first magnetic induction coil and the phase of the third magnetic induction coil, and the second phase difference refers to the difference between the amplitude of the second magnetic induction coil and the amplitude of the fourth magnetic induction coil. When the number of magnetic field lines incident on the first magnetic induction coil and the second magnetic induction coil are the same and the incident angle is the same, it can be determined that the magnetic field entering the magnetic housing 12 is perpendicular to the sensing surface of the magnetic field sensor 13, the first amplitude difference is consistent with the second amplitude difference, and the first phase difference is consistent with the second phase difference, thus eliminating the possibility of interfering magnetic field signals from other directions entering the magnetic housing 12.

[0048] It should be noted that when the number of magnetic field lines incident on the first magnetic field coil and the second magnetic field coil are inconsistent, as are the incident angles, it is usually because magnetic field lines that interfere with the magnetic field signal have entered the magnetic field coil.

[0049] It should be further explained that calculating the phase difference and amplitude difference between two antennas using a differential method can improve the directivity of electric field measurement. The differential calculation method in this embodiment is prior art, specifically referring to publication number CN119727294A. The differential circuit in the control circuit performs differential operations on the gate sampling voltage and drain sampling voltage of the power device to output the drain-gate voltage. Based on this, the drain-gate voltage is processed by a differentiating circuit or a differential-multiplication circuit. The differential component of the drain-gate voltage is used to calculate the amplitude of the compensation current to control its amplitude difference with the Miller current within a preset range. Furthermore, a phase reversal design is introduced during the processing to make the compensation current and the Miller current out of phase, thereby realizing the calculation and control of phase difference and amplitude difference based on a differential method. The difference between this solution and the prior art lies in the different application scenarios. The differential calculation method in this embodiment is applied to the calculation of phase difference and amplitude between two antennas, while the prior art is applied to the calculation of drain-gate voltage between the gate sampling voltage and the drain sampling voltage.

[0050] In a more specific embodiment, an electric field shielding layer 17 is provided on the outer or inner side of the magnetic housing 12. The electric field shielding layer 17 is used to prevent the electric field outside the magnetic housing 12 from interfering with the measurement of the fault magnetic field signal 11 by the magnetic field signal sensor.

[0051] Understandably, in practical implementation, although the core principle of the Hall sensor is based on a magnetic field, its physical structure (pins, wires) and internal electronic circuitry make it equally sensitive to rapidly changing electric fields (high-frequency noise). This interference mainly enters the signal lines and power lines through capacitive coupling or directly penetrates the package, affecting the internal circuitry. In high-noise power electronic equipment environments, electric field interference is a problem that cannot be ignored. This embodiment avoids electric field interference with the magnetic field measurement within the magnetically conductive housing 12 by setting an electric field shielding layer 17.

[0052] In a more specific embodiment, both the first magnetic field shielding layer 5 and the second magnetic field shielding layer 6 are made of permalloy material.

[0053] In a more specific embodiment, the electric field shielding layer 17 is made of metal, forming a metal shell (Faraday cage). The electric field shielding layer 17 is grounded, terminating the external electric field on the surface of the metal shell to eliminate external induced charges. This creates a zero-electric-field environment inside the metal shell as much as possible, reducing the distributed capacitance coupling between the interference source and the sensitive device, and further enhancing the directivity of the measurement. Therefore, the metal shell effectively suppresses electric field noise and solves the problem of cross-interference between the external electric field and the magnetic field measurement.

[0054] In a more specific embodiment, the positions of the first antenna 15, the second antenna 16, and the magnetic field sensor 13 are strictly aligned with the center of the opening 14 of the magnetic housing 12 to ensure that the magnetic field after being focused is perpendicularly incident on the sensitive sensing surface of the magnetic field sensor 13.

[0055] Therefore, through the processing and synergistic optimization of the above-mentioned parts, the magnetic field signal detection accuracy in this embodiment is calculated as follows: Magnetic circuit focusing and signal enhancement ÷ (Electric field shielding to reduce noise) × (Differential antenna improving directional resolution). The electromagnetic induction probe 1 in this embodiment has high sensitivity, capable of detecting extremely weak magnetic field changes. It enables detection of lines under energized conditions, accurately sensing weak magnetic field changes in specific areas below overhead lines. Especially under high voltage and high current conditions, it effectively captures magnetic field signals related to the line's operating status, avoiding stray magnetic field interference from the external environment, ensuring the accuracy of signal acquisition, and providing accurate raw data for subsequent fault detection. The usage status of the electromagnetic induction probe 1 in this embodiment is as follows: Figure 2 As shown, traditional detection methods often require power outages. In this embodiment, the electromagnetic induction probe 1 does not require a power outage during detection, thus avoiding the impact of power outages on the power supply, improving power supply reliability, and reducing the inconvenience and economic losses caused to users by power outages.

[0056] In a more specific embodiment, such as Figure 4As shown, the signal output terminals of the magnetic field sensor 13 and the differential dual antenna structure are both connected to the signal processing component, which includes a signal conditioning circuit, an analog-to-digital converter, a microprocessor unit, a data storage unit, and a communication module.

[0057] The input terminal of the signal conditioning circuit is connected to the signal output terminal of the magnetic field sensor 13 and the differential dual antenna structure, respectively. The output terminal of the signal conditioning circuit is connected to the input terminal of the analog-to-digital converter. The output terminal of the analog-to-digital converter is connected to the input terminal of the microprocessor unit. The microprocessor unit is connected to the communication module through the data storage unit.

[0058] The signal conditioning circuit is used to receive the original signal and perform filtering, amplification and gain processing. The analog-to-digital converter is used to convert the conditioned analog signal into a digital signal. The microprocessor unit is used to determine whether there is a fault in the line based on the digital signal. The data storage unit is used to store historical data. The communication module is used to transmit data to the remote monitoring center.

[0059] Understandably, in practice:

[0060] The signal conditioning circuit includes an amplification module, a filtering module, and a gain module. Since the magnetic field signals acquired by the magnetic field sensor and the differential dual-antenna structure are typically weak, the signal conditioning circuit amplifies and filters these signals to enhance and purify them, removing noise interference and improving signal quality and discernibility. Furthermore, the circuit features signal gain adjustment, enabling adaptive gain control (AGC) based on the detected magnetic field signal in varying intensities. This ensures the output signal remains within a suitable range, facilitating subsequent analog-to-digital conversion and data processing, and guaranteeing the adaptability and accuracy of the entire detection system to magnetic field signals of different intensities.

[0061] An analog-to-digital converter (ADC) converts a conditioned analog signal into a digital signal for processing and analysis by a microprocessor. By appropriately selecting a sampling frequency between several kHz and tens of kHz, it can accurately capture detailed information about magnetic field changes without compromising the system's real-time performance and processing efficiency due to excessive data volume. This achieves a balance between timeliness and processing efficiency, enabling highly efficient digital conversion of magnetic field signals and laying the foundation for subsequent intelligent fault detection and analysis.

[0062] The microprocessor unit (MCU) receives the digital signal converted by the ADC and runs a fault detection algorithm. This algorithm analyzes the amplitude, frequency, and phase characteristics of the magnetic field signal, comparing it with a reference characteristic value of the magnetic field signal during normal operation to determine if there is a deviation exceeding a set threshold, thus detecting line faults. It can also preliminarily determine the fault type, such as a significant increase in magnetic field strength during a short-circuit fault, or the disappearance or abnormal fluctuation of the magnetic field signal during an open-circuit fault, providing important information for rapid fault location and repair.

[0063] The data storage unit utilizes high-capacity storage media to facilitate subsequent analysis and backtracking, storing both raw data and processed results from the testing process. Each data entry is timestamped for easy chronological querying and backtracking. This allows operators to subsequently query and analyze historical data, tracing changes in the line's operational status, and gaining a deeper understanding of the line's long-term operational condition, providing data support for power system maintenance and optimization.

[0064] The communication module, equipped with wireless communication capabilities, can transmit detected fault information to the remote monitoring center in real time. This allows monitoring center staff to promptly understand the fault status of the lines, respond quickly, and arrange maintenance personnel for fault repair, improving the timeliness and efficiency of power system fault handling and ensuring the stable operation of the power system.

[0065] Phase verification plays a fundamental and preventative role in fault detection by confirming the phase relationship of lines or equipment in a power system. It can prevent "human-caused faults" such as short circuits and equipment burnout caused by phase errors (such as phase sequence reversal or phase misalignment) in advance, reducing the occurrence of faults at the source. At the same time, the standard phase relationship it establishes can serve as a benchmark for fault analysis. When a short circuit or ground fault occurs in a line, it can quickly locate the faulty phase and fault type by comparing the phase anomalies (such as current phase shift or phase sequence disorder) at the time of the fault. It can also ensure that protection devices operate reliably based on correct phase logic, avoiding false tripping or failure to trip due to phase confusion, and improving the accuracy and efficiency of fault detection.

[0066] In a more specific embodiment, such as Figure 3As shown, the intelligent network line live fault detection device also includes a phase gauging instrument, which includes a signal acquisition head 31, a telescopic rod 32, a handle 33, a signal receiver 34, and a signal transmitter 35. The signal acquisition head 31 is made of insulating material. The telescopic rod 32, the handle 33, the signal receiver 34, and the signal transmitter 35 are all equipped with insulating shells. The signal acquisition head 31 is connected to one end of the telescopic rod 32 for acquiring the phase signal of the line under test 4. The other end of the telescopic rod 32 is connected to the handle 33. The signal receiver 34 is located near the signal acquisition head 31 for collecting the phase signal. The signal transmitter 35 is located near the handle 33 and is electrically connected to the signal receiver 34. The signal transmitter 35 is used to send the phase signal to the remote monitoring center.

[0067] In a more specific embodiment, the phase gauging instrument also includes a button 36, which is located near the handle 33 and electrically connected to the signal acquisition head 31. The button 36 is used to control operations such as starting and stopping signal acquisition, and the button 36 is also provided with an insulating shell.

[0068] Understandably, the phase locator's housing and probe are made of high-performance, fully insulated materials, effectively preventing leakage and short circuits in high-voltage environments from a physical perspective. This ensures the safety of the instrument and operators, enabling stable and reliable operation in high-voltage energized environments. In confined three-phase electrical environments (such as longitudinally arranged overhead lines or longitudinally arranged busbars in high-voltage switchgear), the instrument can safely determine the phase, ensuring phase-to-phase safety and personal safety even if another phase is accidentally touched while testing a particular phase. During testing, even if the testing components simultaneously contact two phases, it will not cause safety accidents to personnel or equipment, thus ensuring the entire testing process is safe and reliable, enabling phase locator testing under energized conditions.

[0069] It should be noted that in practical applications, the magnetic field sensor 13 is placed below the line to achieve non-contact detection. The line includes a three-phase transmission circuit. The magnetic field sensor 13 detects the fault magnetic field signal 11, which can only determine that there is a fault in the line position above the magnetic field sensor 13, but cannot determine which phase is faulty. Therefore, it is necessary to further use a phase comparison instrument to conduct contact detection on each of the three-phase transmission lines in the line. The signal acquisition head 31 contacts the single-phase transmission line to quickly locate the faulty phase, that is, to quickly locate the faulty single-phase transmission line in the line, and then repair the faulty single-phase transmission line.

[0070] In a more specific embodiment, the detection signal accessory used has no metal structure, requires no external acquisition device, and is completely insulated.

[0071] In a more specific embodiment, the phase sequence determination and verification circuit is optimized by selecting high-quality circuit boards and components, and by implementing reasonable shielding and isolation measures in the circuit layout to improve its anti-interference performance and insulation characteristics. This enables the instrument to accurately complete the phase sequence determination and verification task even in complex power environments with electromagnetic interference, electric field interference, etc., ensuring the accurate determination of the phase sequence of the power system and providing critical data support for the normal operation of the power system.

[0072] In a more specific embodiment, safety devices such as overvoltage protection and overcurrent protection are provided. When the voltage or current of the instrument exceeds the normal operating range, these protective devices can be activated quickly to cut off the circuit, preventing damage to the instrument due to excessive voltage or current surges, further enhancing the safety and stability of the instrument during use.

[0073] In a more specific embodiment, in actual testing, the electromagnetic field receiving antenna has a high impedance, making the received signal prone to distortion. The influence of the environment on the test results (such as terrain, temperature, humidity, etc.) lacks internationally available data and theory, requiring extensive test data analysis. In this research project, in-depth digital processing of the signal was performed, employing Fast Fourier Transform (FFT) technology to calculate the waveform. This method effectively analyzes the frequency components of the signal, and the calculated waveform data is further processed using the sliding integral method. The sliding integral is a commonly used technique in time series data processing; it integrates data within a certain time window to smooth data fluctuations, thereby reducing the impact of noise. This combination of FFT and sliding integral effectively identifies and filters out invalid data points and data points with excessively large differences that may represent outliers, thus improving the accuracy and reliability of signal processing.

[0074] In conclusion, this invention, through in-depth research on the full insulation phase-fixing function and the live-line fault detection function, optimizes and innovates multiple aspects from hardware design to software algorithms. It aims to improve the safety, accuracy, and real-time performance of power system detection, providing strong support for the reliable operation of the power system. Furthermore, the various functional modules work together to form a complete and efficient power system detection system. This intelligent device can detect whether a line has a fault while it is energized, ensuring the safety of workers, reducing the number of power outages for residents, and detecting faults in overhead lines while the line is energized, providing early warnings and ensuring the reliability of electricity supply for users.

[0075] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A smart network line live fault detection device, characterized in that, Includes an electromagnetic induction probe, which includes a magnetic housing and a magnetic field sensor; The magnetic housing has an opening for approaching and facing the circuit under test; the magnetic field sensor is disposed inside the magnetic housing; the sensing surface of the magnetic field sensor faces the opening. The magnetically conductive housing is used to form a low magnetic reluctance cavity through its high magnetic permeability characteristics, guiding the fault magnetic field signal of the circuit under test to flow through the opening into the magnetically conductive housing and concentrate it onto the magnetic field sensor. At the same time, it is used to guide the interference magnetic field signal away from the opening to the outer wall of the magnetically conductive housing, preventing the interference magnetic field signal from entering the magnetically conductive housing. The sensing surface of the magnetic field sensor is parallel to the plane of the opening. A differential dual-antenna structure is also provided inside the magnetic housing. The differential dual-antenna structure includes a first antenna, a second antenna, and a processor. Both the first antenna and the second antenna are used to measure the amplitude and phase of the fault magnetic field signal. The first antenna and the second antenna are distributed on both sides of the magnetic field sensor along the line connecting the opening and the magnetic field sensor. The first antenna is located on the side of the magnetic field sensor closer to the opening, and the second antenna is located on the side of the magnetic field sensor away from the opening. The first antenna is connected to the second antenna through the processor. The processor is used to determine whether the direction of the fault magnetic field signal is perpendicular to the sensing surface of the magnetic field sensor by comparing whether the phase and amplitude of the first antenna and the second antenna are consistent.

2. The intelligent network line live fault detection device according to claim 1, characterized in that, The second antenna has a first magnetic field shielding layer on the side closest to the magnetic field sensor.

3. The intelligent network line live fault detection device according to claim 2, characterized in that, The first antenna includes a first magnetic induction coil and a second magnetic induction coil, and the second antenna includes a third magnetic induction coil and a fourth magnetic induction coil. The processor includes a first calculator, a second calculator, and a comparator. The first magnetic induction coil and the third magnetic induction coil are correspondingly arranged, and the second magnetic induction coil and the fourth magnetic induction coil are correspondingly arranged. The first calculator is arranged between the first magnetic induction coil and the third magnetic induction coil, and the second calculator is arranged between the second magnetic induction coil and the fourth magnetic induction coil. The first calculator is connected to the second calculator through the comparator. The first calculator is used to calculate a first phase difference and a first amplitude difference, and the second calculator is used to calculate a second phase difference and a second amplitude difference. The comparator is used to determine whether the direction of the fault magnetic field signal is perpendicular to the sensing surface of the magnetic field sensor by judging whether the first amplitude difference and the second amplitude difference and the first phase difference and the second phase difference are consistent.

4. The intelligent network line live fault detection device according to claim 3, characterized in that, A second magnetic field shielding layer is provided on the side of the first antenna closest to the magnetic field sensor.

5. A smart network line live-line fault detection device according to any one of claims 1-4, characterized in that, An electric field shielding layer is provided on the outer or inner side of the magnetically conductive housing. The electric field shielding layer is used to prevent the electric field outside the magnetically conductive housing from interfering with the measurement of the fault magnetic field signal by the magnetic field sensor.

6. A smart network line live-line fault detection device according to any one of claims 1-4, characterized in that, The magnetically conductive shell is made of permalloy material.

7. The intelligent network line live fault detection device according to claim 1, characterized in that, It also includes a phase gauging instrument, which comprises a signal acquisition head, a telescopic rod, a handle, a signal receiver, and a signal transmitter. The signal acquisition head is made of insulating material. The telescopic rod, handle, signal receiver, and signal transmitter are all equipped with insulating shells. The signal acquisition head is connected to one end of the telescopic rod for acquiring the phase signal of the circuit under test. The other end of the telescopic rod is connected to the handle. The signal receiver is located near the signal acquisition head for collecting the phase signal. The signal transmitter is located near the handle and is electrically connected to the signal receiver. The signal transmitter is used to send the phase signal to a remote monitoring center.

8. A signal processing system for processing magnetic field signals acquired by the intelligent network line live fault detection device according to any one of claims 1-7, characterized in that, The system includes a signal processing component, wherein the signal output terminals of the magnetic field sensor and the differential dual antenna structure are both connected to the signal processing component, and the signal processing component includes a signal conditioning circuit, an analog-to-digital converter, and a microprocessor unit. The input terminal of the signal conditioning circuit is connected to the signal output terminal of the magnetic field sensor and the differential dual antenna structure, respectively. The output terminal of the signal conditioning circuit is connected to the input terminal of the analog-to-digital converter, and the output terminal of the analog-to-digital converter is connected to the input terminal of the microprocessor unit. The signal conditioning circuit is used to receive the original signal and perform filtering, amplification and gain processing. The analog-to-digital converter is used to convert the conditioned analog signal into a digital signal. The microprocessor unit is used to determine whether there is a fault in the line based on the digital signal.

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