Wide-range wireless high-voltage leakage current detection system

Abstract

The invention relates to the field of electric leakage detection, and provides a wide-range wireless high-voltage leakage current detection system, which comprises a host detector fixedly mounted on an insulating rod; wherein the host detector is provided with a front-end sensing module; the front-end sensing module comprises a square magnetic circuit bayonet for clamping a high-voltage wire and collecting a leakage current signal, a built-in soft magnetic alloy magnetic core and a winding coil; and the receiver is in wireless communication with the host detector and is used for receiving the leakage current signal. According to the invention, remote operation is realized through the insulating rod and the square magnetic circuit bayonet, and the square bayonet solves the problem of multi-line measurement. The soft magnetic alloy magnetic core and the winding coil are matched with each other through the magnetic core with high magnetic conductivity, so that wide-range and high-precision signal acquisition is realized, and a reliable data source is provided for wireless transmission; and the host and the wireless receiver transmit the acquired data to the ground in real time through the wireless communication module, so that the cost of communication between the high altitude and the ground is eliminated.

Description

Technical Field

[0001] This invention relates to the field of leakage current detection, and in particular to a wide-range wireless high-voltage leakage current detection system. Background Technology

[0002] In power systems, 380V three-phase four-wire lines are widely used in industrial and residential power distribution. Due to long-term operation or improper human intervention (such as unauthorized connections, insulation aging, and leakage), abnormal leakage current is often observed. Leakage current not only leads to energy loss but can also cause electric shock or electrical fires, thus requiring regular inspection. Traditional leakage current detection methods have the following drawbacks: 1. Difficulty in high-altitude inspection: Cables are often installed at high altitudes, requiring manual climbing for operation, which poses a risk of falling from heights, and it is difficult to directly contact live wires; 2. High safety risk: When using a regular clamp meter for measurement, the operator needs to be close to the live part, which can easily lead to accidental contact or electric shock due to insulation failure; 3. Inconvenient data acquisition: Values ​​need to be read and recorded on-site during testing, making real-time monitoring impossible, and frequent communication between personnel at high altitudes and on the ground is required, resulting in low efficiency; Traditional clamp meters have small jaws: When using a four-wire cable, a traditional clamp meter cannot clamp all four wires simultaneously for measurement because the jaw size is insufficient.

[0003] Among existing publicly available technologies, some solutions use clamp-on current sensors, requiring operators to have close contact with the wires; others use insulated rods to mount ordinary sensors, but these only support local display and cannot transmit data remotely. A few solutions support wireless transmission, but the measuring jaws are too small to simultaneously measure four high-voltage lines. Therefore, there is an urgent need for a comprehensive solution integrating insulated rod mounting, high-precision leakage current detection, wireless remote communication, and large-jaw multi-line measurement to improve detection safety, efficiency, and anti-theft capabilities. Summary of the Invention

[0004] This application proposes a wide-range wireless high-voltage leakage current detection system. The detection module is mounted on an insulated rod, eliminating the need for operators to directly contact 380V live wires and avoiding the risk of electric shock. Through wireless communication technology, high-altitude detection data is transmitted in real-time to the ground, allowing operators to directly observe leakage current values ​​from a safe area, avoiding repeated communication between high-altitude and ground personnel and improving efficiency. The clamp uses a square magnetic circuit design with wound coils at both ends, capable of clamping up to four cables simultaneously. It is also lightweight and easy to operate.

[0005] To achieve the above objectives, this application provides the following technical solution: In a first aspect, this application proposes a wide-range wireless high-voltage leakage current detection system, comprising: A main unit detector is fixedly installed on an insulating pole; the main unit detector is equipped with a front-end sensing module. The front-end sensing module includes a data acquisition unit and a circuit unit; among which, The acquisition unit includes a square magnetic circuit bayonet structure for clamping the high-voltage line and acquiring leakage current signals, as well as a built-in soft magnetic alloy core and wound coil. The circuit section includes a first-stage amplifier circuit and a second-stage amplifier circuit. The first-stage amplifier circuit automatically switches the gain mode according to the amplitude of the input signal; wherein, When the leakage current signal is at the first range, the first-stage amplifier circuit starts the high-gain small-signal mode. When the leakage current signal is in the second range, the first-stage amplifier circuit and the second-stage amplifier circuit activate the low-gain large-signal mode. The maximum value of the first range is equal to the minimum value of the second range; The receiver communicates wirelessly with the host detector and is used to receive leakage current signals.

[0006] In conjunction with the first aspect, the square magnetic circuit bayonet structure includes a main support frame, support arms, a square magnetic circuit bayonet, and a tension spring arranged symmetrically at the top and bottom; wherein, The main support frame is made of high-strength insulating material, with a strip magnetic core and wound coil inserted and fixed inside. The length of a single main support frame is 160cm. The square magnetic circuit bayonet is fixed to the lower main body bracket by screws, the lower end of the bracket arm is connected to the square magnetic circuit bayonet by a rotating shaft, and the contact surface between the upper extension and the upper main body bracket is highly polished. The two ends of the tension spring are connected to the square magnetic circuit bayonet and the support arm respectively. When the bayonet is closed by the spring tension, the air gap of the magnetic circuit is ≤0.1mm.

[0007] In conjunction with the first aspect, the square magnetic circuit bayonet structure also includes an insulating support rod, which forms a composite mechanical structure with the main support frame. The insulating support rods are made of the same high-strength insulating material as the main support and are arranged diagonally along the square magnetic circuit bayonet. The two ends of the intersecting insulating support rods are respectively connected to the upper and lower main supports through mortise and tenon structures. The contact surface of the mortise and tenon structure is coplanar with the polished contact surface of the support arm. When the tension of the tension spring is transmitted to the main support through the support arm, the deformation direction of the composite mechanical structure is consistent with the closing direction of the magnetic circuit air gap. Moreover, the elastic modulus of the insulating support rod is matched with the thermal expansion coefficient of the main support, so that the magnetic circuit air gap is in the preset stable range when the ambient temperature changes from -20℃ to 100℃.

[0008] In conjunction with the first aspect, the soft magnetic alloy core is made of a high-permeability soft magnetic precision alloy material to determine the first magnetic induction intensity threshold. A soft magnetic alloy core is uniformly wound with an enameled wire coil to increase the first magnetic induction intensity threshold to a second magnetic induction intensity threshold; wherein the second magnetic induction intensity threshold is greater than the first magnetic induction intensity threshold.

[0009] In conjunction with the first aspect, the host detector further includes a first power management system, a signal conditioning circuit, a main control MCU, and a first communication module, wherein the first power management system, the signal conditioning circuit, and the first communication module are electrically connected to the main control MCU. The signal conditioning circuit is electrically connected to the front-end sensing module and converts the induced current of the square magnetic circuit bayonet into a target voltage that conforms to the sampling standard of the main control MCU. The first communication module is used to encode and modulate the target voltage into a 433MHz carrier wave and convert it into a target electromagnetic wave for transmission to the receiver.

[0010] In conjunction with the first aspect, the first-stage amplifier circuit and the soft magnetic alloy core form a cooperative induction structure: The soft magnetic alloy core converts the weak leakage current of the cable under test into an initial magnetic induction intensity through its high magnetic permeability. The initial magnetic flux density is coupled to the signal conditioning circuit via a wound coil; The symmetrical structure of the first-stage amplifier circuit and the positive and negative voltage conditioning circuit convert the induced current corresponding to the initial magnetic induction intensity into a differential voltage signal. The differential voltage signal is gain-adjusted through a negative feedback loop consisting of an operational amplifier and a resistor network, which improves the signal-to-noise ratio of the differential voltage signal to the sampling threshold range of the ADC of the main control MCU. Furthermore, the resistor network of the negative feedback loop matches the hysteresis loss and temperature drift of the soft magnetic alloy core, enabling the induced signal to achieve the target accuracy.

[0011] In conjunction with the first aspect, the receiver includes a second power management system, a second communication module, and a data display unit; wherein the second power management system is electrically connected to the second communication module and the data display unit respectively; The second communication module is used to capture the target electromagnetic waves and convert them into visual data; The data display unit is used to display visualized data via an LCD screen; the visualized data includes measured values, AC, battery voltage, stored data, and marker symbols.

[0012] In conjunction with the first aspect, the receiver's second communication module and the data display unit form a data verification closed loop: After demodulating the target electromagnetic wave signal, the second communication module compares the demodulated data with a preset checksum generation algorithm through the main control MCU; the checksum generation algorithm is dynamically adjusted based on the byte length of the demodulated data and the carrier frequency characteristics of the wireless transmission. When the comparison results match, the main control MCU triggers the backlight module of the LCD display to flash at a preset frequency; among which, The flicker frequency is positively correlated with the rate of change of the effective value of leakage current in the demodulated data. When the data display unit displays the stored data, it simultaneously calls the check code generation algorithm to perform secondary verification on the historical stored data, so as to mark the abnormal data segment on the LCD screen with special symbols.

[0013] In conjunction with the first aspect, the receiver is also used for: The target characteristic waveform of the leakage current signal is determined by a sampling frequency not lower than a preset frequency; wherein, the preset frequency is the target sampling frequency that covers the high-frequency peak of the leakage current signal. The target waveform features are decomposed into multiple intrinsic mode function components through multimodal decomposition, and the intrinsic mode function components are normalized and calculated to generate multiple feature vectors. Multiple feature vectors are passed through a trained leakage current classifier and optimized using a sparrow search algorithm to output leakage current identification factors. Based on the leakage current identification factors, the corresponding protection trigger items are matched; among them, the protection trigger items and the leakage current factors have a synchronous triggering mechanism.

[0014] In conjunction with the first aspect, the first-stage amplifier circuit is composed of a positive voltage conditioning circuit and a negative voltage conditioning circuit arranged in a symmetrical structure; The negative voltage conditioning circuit includes an operational amplifier, a clamping diode, and a resistor network. The clamping diode is connected in reverse series between the output terminal of the operational amplifier and the ground terminal. The input terminal of the operational amplifier is electrically connected to the resistor network. When the absolute value of the input voltage is less than 1.75V, the amplification factor of the first-stage amplifier circuit is -1.4491; When the absolute value of the input voltage is greater than 1.75V, the amplification factor of the first-stage amplifier circuit switches to -0.1423; The second-stage amplifier circuit is a second-order Sallen-Key low-pass filter circuit composed of operational amplifiers.

[0015] The beneficial effects of this invention are as follows: This application achieves remote operation through an insulating rod and a square magnetic circuit bayonet, with the square bayonet solving the problem of multi-line measurement. A soft magnetic alloy core and a wound coil, with the high-permeability core and coil working together, enable wide-range, high-precision signal acquisition, providing a reliable data source for wireless transmission. The host and wireless receiver transmit the acquired data to the ground in real time via a wireless communication module, eliminating the communication costs between high altitudes and the ground.

[0016] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0019] In the attached diagram: Figure 1 This is a system composition diagram of a wide-range wireless high-voltage leakage current detection system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the insulating rod and the main detection instrument in an embodiment of the present invention; Figure 3 This is a schematic diagram of the shape of the square magnetic circuit gate in an embodiment of the present invention; Figure 4 This is a schematic diagram of the front half of the interface in an embodiment of the present invention; Figure 5 This is a schematic diagram of the reverse half-side of the interface in an embodiment of the present invention; Figure 6 This is a schematic diagram of the support arm in an embodiment of the present invention; Figure 7 This is a first schematic diagram of the extension of the main support in an embodiment of the present invention; Figure 8 This is a second schematic diagram of the extension of the main support in an embodiment of the present invention; Figure 9 This is a schematic diagram of a low-noise instrumentation amplifier circuit in an embodiment of the present invention; Figure 10 This is a block diagram of the low-voltage area leakage intelligent positioning device in an embodiment of the present invention. Detailed Implementation

[0020] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0021] like Figure 10 As shown, this application is mainly used for leakage current detection in low-voltage distribution areas, and belongs to a type of intelligent positioning device for low-voltage distribution area leakage current detection. The intelligent positioning device for low-voltage distribution area leakage current mainly consists of a detector, an insulated handle, and a receiver.

[0022] The tester is the main tester 1, which is fixedly mounted on an insulated handle through a mechanical structure. The insulated handle is responsible for engaging the test circuit. The main tester 1 and the receiver are wirelessly connected.

[0023] like Figure 2 As shown, the insulating handle includes a main unit detector 1, which is fixedly mounted on an insulating rod 2; the top of the insulating rod 2 is fixed to the lower part of the main body bracket 8 through a connection interface 5.

[0024] like Figure 4 and Figure 5 As shown, connection interface 5 is a mechanical quick-release interface, consisting of two parts; the first part is as follows: Figure 4 As shown, the main body is a block structure with three circular through holes on the side for mounting or positioning; one side has a long, narrow groove that forms a riveting structure with another part; the overall structure is T-shaped, providing a certain degree of strength and rigidity. The other side has a cylindrical boss with threaded holes inside. The second part is as follows... Figure 5 As shown, it is a convex structure with an arc-shaped groove on its protruding part, corresponding to the elongated groove in the first part. One side of the convex structure has three elliptical holes, corresponding to the three circular through holes in the first part, allowing for bolt connection. Connection interface 5 is a detachable connection structure, facilitating disassembly, assembly, and maintenance of the device.

[0025] The main support frame 8 is composed of multiple steel pipes, consisting of upper and lower sections, each with three steel pipes. The middle steel pipe of the lower section is fixed by fitting a long strip groove in the first part and an arc-shaped groove in the second part of the connecting interface 5. The upper and lower sections are connected by insulating support rods 6, which are I-shaped and symmetrical on both sides of the main support frame 8. The steel pipes on both sides are fixedly connected by support arms 4. The insulating support rods 6 are used for support and insulation, ensuring an effective insulation distance between the operator and live parts. like Figure 7 and Figure 8 As shown, the main support 8 has symmetrical steel pipes on the left and right sides, with steel pipe sections and rectangular fixing sections; the rectangular fixing sections and the fixing sections on both sides of the support arm 4 are fixed by bolts.

[0026] like Figure 6 As shown, a square magnetic circuit slot 3 can be fixed on one side of the support arm 4, and a detection slot 7 is present on the square magnetic circuit slot 3; the other side can be fixedly connected to the steel pipes on the left and right sides of the main support 8. like Figure 3 As shown, the detection bayonet 7 is specifically a cross-shaped groove on one side of the square magnetic circuit bayonet 3. A bayonet limiting block is provided on the cross-shaped groove; it is used to hold the component to be tested, and can hold bolts, wire clamps, etc. of overhead lines to detect leakage signals. The shape of the detection bayonet 7 is adapted to the shape of the component to be tested.

[0027] Leakage detection in low-voltage distribution areas mainly relies on the wide-range wireless high-voltage leakage current detection system proposed in this application. The specific implementation process is as follows: Example 1: First aspect, such as Figure 1 and Figure 2 As shown, this application proposes a wide-range wireless high-voltage leakage current detection system, comprising: The main unit detector 1 is fixedly installed on the insulating rod 2; wherein, the main unit detector 1 is equipped with a front-end sensing module; In one embodiment of this application, the detection system integrates insulating rod support, high-voltage leakage current acquisition, and wireless data transmission functions, making it suitable for leakage current detection of 380V three-phase four-wire lines. The main unit detector 1 collects leakage current signals from high-voltage cables and transmits them wirelessly to a receiver for remote monitoring. This solves problems such as the risks of high-altitude operations, inconvenient data acquisition, and limitations in access size in traditional detection methods, improving detection safety and efficiency.

[0028] In one embodiment of this application, the main unit detector 1 mainly consists of a power management system, a front-end sensing module, a signal conditioning circuit, and a main control and communication module. The detection module, mounted on the top of the insulating rod 2, is mechanically fixed to the insulating rod 2 and is used for high-altitude cable inspection. The insulating rod 2 is made of high-strength insulating material, isolating the main unit detector 1 from the operator and ensuring a safe distance from high-voltage conductors during inspection. This avoids direct contact between the operator and live wires, eliminating the risk of electric shock; it also eliminates the need for climbing, reducing the risk of falls from heights.

[0029] The front-end sensing module includes a data acquisition unit and a circuit unit; among which, The acquisition unit includes a square magnetic circuit bayonet structure for clamping the high-voltage line and acquiring leakage current signals, as well as a built-in soft magnetic alloy core and wound coil. The circuit section includes a first-stage amplifier circuit and a second-stage amplifier circuit. The first-stage amplifier circuit automatically switches the gain mode according to the amplitude of the input signal; wherein, When the leakage current signal is at the first range, the first-stage amplifier circuit starts the high-gain small-signal mode. When the leakage current signal is in the second range, the first-stage amplifier circuit and the second-stage amplifier circuit activate the low-gain large-signal mode. In one embodiment of this application, the square magnetic circuit bayonet structure of the front-end sensing module is used to clamp multiple high-voltage lines and form a closed magnetic circuit. It employs a hinged design and a spring-loaded structure, with highly polished contact surfaces when closed to ensure the integrity of the magnetic circuit. The square structure accommodates four cables passing through simultaneously, collecting leakage current through electromagnetic induction. This solves the problem of the traditional clamp meter's bayonet being too small, enabling multi-line synchronous detection and improving detection efficiency.

[0030] In one embodiment of this application, the first-stage amplifier circuit is responsible for wide dynamic range signal conditioning and is used to execute a nonlinear gain automatic switching mechanism. The second-stage amplifier circuit is responsible for signal optimization to achieve low-pass filtering and eliminate high-frequency interference; in small-signal mode, the input voltage is <1.75V, and the range is 0.01mA-100mA leakage current, which is used to provide high sensitivity and improve the small-signal signal-to-noise ratio by 8dB; in large-signal mode, the input voltage is >1.75V, and the range is 100mA-2000mA leakage current, which can prevent signal saturation and retain the 8-bit effective resolution of the 12-bit ADC.

[0031] The receiver, which communicates wirelessly with the host detector 1, is used to receive leakage current signals.

[0032] In one embodiment of this application, the soft magnetic alloy core is a bar-shaped core made of a high-permeability soft magnetic precision alloy material, placed inside a square bayonet. It utilizes the high permeability of the soft magnetic material to convert weak leakage current into detectable magnetic flux density; its low coercivity reduces hysteresis loss, ensures signal linearity, and improves the sensitivity of weak leakage current detection.

[0033] In one embodiment of this application, an enameled wire coil is uniformly wound on a soft magnetic alloy core, with the number of turns designed according to the measurement range. Based on the law of electromagnetic induction, the coil converts the change in magnetic flux induced in the core into an induced current, which is then transmitted to a signal conditioning circuit to convert the magnetic signal into an electrical signal.

[0034] In one embodiment of this application, the receiver is a ground-based receiving device independent of the host, receiving the leakage current signal transmitted by the host via a wireless module. It employs 433MHz wireless communication technology; the host encodes and modulates the processed leakage current data before transmitting it via an RF chip, and the receiver demodulates the data and displays it on an LCD. This enables remote real-time transmission of detection data, eliminating the need for operators to communicate with the ground from high altitudes, thus improving efficiency; it is also used for safe area monitoring, avoiding close contact with high-voltage environments.

[0035] The beneficial effects of the above scheme are as follows: This application achieves remote operation through an insulating rod 2 and a square magnetic circuit bayonet 3, with the square bayonet solving the problem of multi-line measurement. A soft magnetic alloy core and a wound coil, with the high-permeability core and coil working together, enable wide-range, high-precision signal acquisition, providing a reliable data source for wireless transmission. The host and wireless receiver transmit the acquired data to the ground in real time via a wireless communication module, eliminating communication costs between high altitudes and the ground. The circuitry of this application achieves range switching through two different ranges and different signal modes to meet wide-range detection requirements. Furthermore, the soft magnetic alloy core and wound coil, with the high-permeability core and coil working together, achieve high precision and further increase the range.

[0036] Example 2: The square magnetic circuit bayonet structure includes a main body support 8, a support arm 4, a square magnetic circuit bayonet 3, and a tension spring arranged symmetrically at the top and bottom; wherein, The main support 8 is made of high-strength insulating material, and a strip magnetic core and a wound coil are installed and fixed inside it. The length of a single main support 8 is 160cm. In one embodiment of this application, the main support 8 is a strip-shaped support structure made of high-strength insulating material, symmetrically arranged vertically, and hollow inside to accommodate the strip magnetic core and the wound coil. The high-strength insulating material balances mechanical strength and electrical insulation performance. Structurally, the symmetrical arrangement ensures uniform force distribution at the bayonet, allowing four high-voltage lines to pass through simultaneously. The built-in magnetic core and coil form a closed magnetic circuit, collecting leakage current signals based on the principle of electromagnetic induction.

[0037] The square magnetic circuit bayonet 3 is fixed to the lower main body bracket 8 by screws, the lower end of the bracket arm 4 is connected to the square magnetic circuit bayonet 3 by a rotating shaft, and the contact surface between the upper extension and the upper main body bracket 8 is highly polished. In one embodiment of this application, the support arm 4 is a lever structure made of engineering plastic. Its lower end is movably connected to the card holder via a pivot, and its upper extension contacts the main support 8. The contact surface is precision polished. The pivot connection enables the opening and closing function of the card slot, facilitating cable insertion; the polished contact surface reduces the mechanical gap during magnetic circuit docking, lowers magnetic resistance, and ensures efficient magnetic flux coupling.

[0038] The two ends of the tension spring are connected to the square magnetic circuit bayonet 3 and the support arm 4 respectively. When the bayonet is closed by the spring tension, the air gap of the magnetic circuit is ≤0.1mm.

[0039] In one embodiment of this application, the square magnetic circuit bayonet 3 is a fixing base made of engineering plastic, which is rigidly connected to the lower main body bracket 8 by screws, serving as the mounting carrier for the bracket arm 4 and the spring. The screw connection provides stable mechanical support, ensuring that the force direction of the bracket arm 4 and the spring is consistent with the magnetic circuit closing direction, avoiding structural loosening when the bayonet opens and closes, and ensuring the stability of the magnetic circuit air gap during long-term use.

[0040] In one embodiment of this application, a metal tension spring is used, with its elastic coefficient designed according to the weight of the bayonet and the closing force of the magnetic circuit. Its two ends are connected to the bayonet seat and the support arm 4, respectively. Continuous tension ensures that the upper end of the support arm 4 is tightly fitted to the main support 8, controlling the air gap in the magnetic circuit to ≤0.1mm. The air gap is the main source of magnetic resistance in the magnetic circuit; the smaller the air gap, the higher the magnetic permeability and the stronger the induced signal.

[0041] In one embodiment of this application, the front-end sensing module is the core of the product, including a magnetic core, a detection coil, and a bayonet. The magnetic core is made of a soft magnetic precision alloy material with excellent performance. This magnetic material has high permeability and extremely low coercivity, as well as low hysteresis loss and low core loss. Under its weak magnetic field, it can also generate a strong magnetic induction intensity, exhibiting high sensitivity and high saturation magnetic induction intensity.

[0042] Through precise component design and complex manufacturing process, its excellent performance is achieved. Then, N turns of enameled wire are evenly and tightly wound on it. Based on the law of electromagnetic induction, when the cable under test is placed in the bayonet coil, the current in the wire will generate an alternating magnetic flux, thereby inducing an electromotive force in the coil.

[0043] Because of its high permeability, the magnetic core can generate a sufficiently large alternating magnetic flux and electromotive force even with a small current.

[0044] Because the aperture of a conventional leakage current detector is too small, it is impossible to secure the cables in the coil when measuring high-voltage electricity at high altitudes. Furthermore, the voltage of the high-voltage cables is too high, making close-range operation unsafe for personnel. Therefore, an insulating rod is used to raise the aperture above the head and secure the four high-voltage cables in the aperture coil. Thus, the design of the aperture is crucial.

[0045] The bayonet uses a square magnetic circuit design with wound coils at both ends. Since the opening and closing of the bayonet introduces an air gap, even a small air gap can reduce the effective permeability of the entire magnetic circuit and affect the sensitivity of the equipment. Therefore, to ensure that the magnetic circuit can close efficiently and with a low air gap when the bayonet is opened and closed, a precision hinge design is used on both sides of the bayonet. The contact surface of the bayonet is highly polished and a spring-loaded structure is used. The tension of the spring is used as the restoring force, so that when the bayonet is closed, the air gap of the magnetic circuit is extremely small and stable, ensuring the high precision of the equipment.

[0046] The bayonet uses a square magnetic circuit design. The upper and lower main supports 8 are mainly used to fix the magnetic core and coil. The wound coil and magnetic core are inserted into the tube of the main support 8 and fixed with glue to enhance its firmness. The total length of each support is 160cm. To ensure that the magnetic circuit can close efficiently and with low air gap when the bayonet opens and closes, a precision hinge design is used on both sides of the bayonet. It mainly includes a square magnetic circuit bayonet 3, a support arm 4, and a tension spring. The lower end of the square magnetic circuit bayonet 3 is fixedly connected to the lower main body bracket 8 by screws. The bar magnetic core is inserted and fixed on the bracket arm 4. A spring-loaded structure is adopted, with the two ends of the tension spring connected to the square magnetic circuit bayonet 3 and the bracket arm 4 respectively. The tension of the spring is used as the restoring force, so that the upper extension of the bracket arm 4 is exposed and stably attached to the contact surface of the upper main body bracket 8. The lower end of the bracket arm 4 is fixed to the square magnetic circuit bayonet 3 by a rotating shaft, and the lower end of its bar magnetic core is exposed and in contact with the lower main body, thereby realizing the open and closed state of the bayonet and ensuring the high precision of the equipment.

[0047] The lead wire of the detection bayonet 7 is connected to the detection circuit box via a waterproof connector. Screws and nuts are used to secure the circuit box to the insulating rod 2 for easy operation. The interface is made of high-strength, high-rigidity, and highly stable engineering plastic. The lower main support 8 passes through a pre-drilled hole in the interface and is fixed with adhesive. The insulating rod 2 is rotated and screwed into the threaded hole under the interface, thus connecting and securing the insulating rod 2 to the bayonet. The two middle insulating support rods 6 primarily serve a supporting function, supporting the upper and lower long column supports and maintaining the stability of the bayonet's square structure.

[0048] The beneficial effects of the above scheme are as follows: This application solves the problem of insufficient signal accuracy by ensuring the mechanical stability of the gate while achieving precise control of the air gap in the magnetic circuit.

[0049] Example 3: The square magnetic circuit bayonet 3 structure also includes an insulating support rod 6, which forms a composite mechanical structure with the main support 8. The insulating support rod 6 of the square magnetic circuit bayonet 3 and the main support 8 form a composite mechanical structure: The insulating support rod 6 is made of the same high-strength insulating material as the main support 8 and is arranged diagonally along the square magnetic circuit slot 3. The two ends of the intersecting insulating support rod 6 are respectively connected to the upper and lower main supports 8 through tenon and mortise structures. The contact surface of the tenon and mortise structure is coplanar with the polished contact surface of the support arm 4. When the tension of the tension spring is transmitted to the main support 8 through the support arm 4, the deformation direction of the composite mechanical structure is consistent with the closing direction of the magnetic circuit air gap. Moreover, the elastic modulus of the insulating support rod 6 matches the thermal expansion coefficient of the main support 8, so that the magnetic circuit air gap is in the preset stable range when the ambient temperature changes from -20℃ to 100℃.

[0050] In one embodiment of this application, the composite mechanical structure includes an insulating support rod 6 made of the same material as the main support 8, which is arranged diagonally along the square magnetic circuit slot 3, and its two ends are connected to the upper and lower main supports 8 by tenon and mortise structures.

[0051] In one embodiment of this application, the insulating support rod 6 is a strip-shaped support made of high-strength insulating material, which intersects along the diagonal direction of the square bayonet to form an X-shaped structure, with a length adapted to the diagonal dimension of the 160cm main support 8. Using the same material as the main support 8 ensures consistent mechanical properties and prevents stress concentration caused by material differences. The diagonal intersection arrangement is based on mechanical principles; the X-shaped structure can decompose vertical external forces into diagonal components, offsetting deformation through the triangular stability effect and improving the overall structural rigidity.

[0052] In one embodiment of this application, the mortise and tenon structure employs a mechanical structure where the connection node between the insulating support rod 6 and the main support 88 uses a tenon and mortise joint. The contact surface is precision machined and coplanar with the polished contact surface of the support arm 4. The mortise and tenon joint achieves a screwless rigid connection through an interference fit, avoiding the risk of loosening in threaded connections. The coplanar design ensures that the spring tension transmitted by the support arm 4 is distributed along the normal direction of the contact surface, preventing air gap displacement caused by additional torque due to the tilt of the contact surface.

[0053] In one embodiment of this application, the mechanical properties indicate that the elastic deformation direction of the main support 8 and the cross support rod under force is parallel to the closing direction of the magnetic circuit air gap, rather than perpendicular or inclined.

[0054] In one embodiment of this application, material matching refers to matching the elastic modulus and the coefficient of thermal expansion. The elastic modulus of the insulating support rod 6 matches the coefficient of thermal expansion of the main support 8, achieving stress compensation under temperature changes. For example, the elastic modulus of the insulating support rod 6 is 15-20 GPa, and the coefficient of thermal expansion of the main support 8 is 5-8 × 10⁻⁻⁻⁻⁶. 6 / ℃.

[0055] The beneficial effects of the above scheme are: This application addresses the limitations of traditional measurement frameworks and material matching, which fail to resolve deformation direction issues and cannot eliminate temperature effects through cross-layouts. By using diagonal cross-layouts to improve structural stiffness and coplanar tenon and mortise joints to enhance force transmission, the deformation direction aligns with the air gap closure direction. Furthermore, in terms of material properties, the elastic modulus matches the thermal expansion coefficient of the main support 8, thus suppressing air gap fluctuations during temperature changes.

[0056] Example 4: The soft magnetic alloy core uses a high-permeability soft magnetic precision alloy material to determine the first magnetic induction intensity threshold; the preferred soft magnetic precision alloy material is permalloy. A soft magnetic alloy core is uniformly wound with an enameled wire coil to increase the first magnetic induction intensity threshold to a second magnetic induction intensity threshold; wherein the second magnetic induction intensity threshold is greater than the first magnetic induction intensity threshold. The first magnetic induction intensity threshold is the set basic detection sensitivity, corresponding to a first measurement range; In one embodiment of this application, the soft magnetic alloy core is a bar core made of a high-permeability soft magnetic precision alloy material, possessing high permeability and low hysteresis loss characteristics. Its inherent magnetic properties determine the first magnetic induction intensity threshold. An auxiliary coil is formed by uniformly winding enameled wire around the core to extend the measurement range to achieve a second measurement range.

[0057] In one embodiment of this application, the enameled wire coil is formed by uniformly winding N turns of high-strength enameled wire along the axial direction outside the magnetic core to form a closed coil structure. The first threshold B1 is raised to the second threshold B2 through electromagnetic coupling to achieve adaptive range switching.

[0058] The beneficial effects of the above scheme are as follows: This application uses a high-permeability material to set the basic sensitivity, and then uses a uniformly wound coil to extend the measurement range and improve the detection sensitivity.

[0059] Example 5: The host detector 1 further includes a first power management system, a signal conditioning circuit, a main control MCU, and a first communication module, wherein the first power management system, the signal conditioning circuit, and the first communication module are electrically connected to the main control MCU. The signal conditioning circuit is electrically connected to the front-end sensing module and converts the induced current of the square magnetic circuit bayonet 3 into a target voltage that conforms to the sampling standard of the main control MCU. The first communication module is used to encode and modulate the target voltage into a 433MHz carrier wave and convert it into a target electromagnetic wave for transmission to the receiver.

[0060] In one embodiment of this application, the power management system of the host detector 1 adopts a low-power design, regulating the 6V voltage of the battery to the 3.3V voltage required by the circuit for powering the chips and the microcontroller. That is, it provides power to the signal conditioning circuit, the first communication module, and the main control MCU.

[0061] In one embodiment of this application, signal conditioning involves converting the induced current of the bayonet coil into a voltage, which is then amplified by a high-precision, low-noise instrumentation amplifier as the first stage of amplification. This amplifies and filters the weak signal from the induction coil, removes high-frequency noise, and amplifies the weak induced signal to a voltage suitable for MCU sampling, thus preparing it for ADC sampling.

[0062] In one embodiment of this application, the main control CPU and the main control chip of the communication module are STM32 series low-power MCUs. The chip has a built-in high-precision ADC with powerful performance. It is responsible for controlling ADC sampling, calculating the true effective value, executing standard algorithms, managing power supply and controlling wireless communication, packaging data (current value, battery status, etc.), and transmitting the data to be sent to the radio frequency chip through the UART interface.

[0063] The communication module first encodes and modulates the data onto a 433MHz carrier wave, then amplifies the power, and finally converts it into electromagnetic waves that are radiated by the antenna. This enables the processed data to be sent from the transmitting end of the 433MHz wireless communication module to the receiving end of a remote receiver.

[0064] The beneficial effects of the above scheme are as follows: This application combines 433MHz carrier communication with wide-range adaptive signal conditioning to achieve wireless transmission of wide-range leakage current under high-voltage conditions.

[0065] Example 6: The first-stage amplifier circuit of the signal conditioning circuit and the soft magnetic alloy core of the front-end sensing module form a cooperative sensing structure: The soft magnetic alloy core converts the weak leakage current of the cable under test into an initial magnetic induction intensity through its high magnetic permeability. The initial magnetic flux density is coupled to the signal conditioning circuit via a wound coil; The symmetrical structure of the first-stage amplifier circuit and the positive and negative voltage conditioning circuit convert the induced current corresponding to the initial magnetic induction intensity into a differential voltage signal. The differential voltage signal is gain-adjusted through a negative feedback loop consisting of an operational amplifier and a resistor network, which improves the signal-to-noise ratio of the differential voltage signal to the range of the ADC sampling threshold of the main control MCU. Furthermore, the interference of the resistor network of the negative feedback loop with the hysteresis loss and temperature drift of the soft magnetic alloy core on the induced signal is canceled out.

[0066] In one embodiment of this application, the magnetic core and amplifier circuit work together in a closed-loop synergy between the magneto-electric conversion characteristics of the soft magnetic alloy core and the electrical signal processing characteristics of the signal conditioning circuit. This achieves efficient extraction of weak signals and noise suppression through matching the magnetic circuit and circuit parameters. The high permeability of the magnetic core converts weak leakage current into a detectable initial magnetic flux density; the symmetrical amplification structure and negative feedback design of the circuit inversely compensate for the nonlinear error of the magnetic core, forming a magneto-electromagnetic synergistic adjustment mechanism.

[0067] In one embodiment of this application, high permeability is converted into initial magnetic flux density. A bar core made of soft magnetic precision alloy material is used to convert the weak magnetic field generated by cable leakage current into initial magnetic flux density through its high permeability. The high permeability characteristic indicates a permeability exceeding 50,000, enabling the weak leakage current to generate a measurable magnetic flux density.

[0068] In one embodiment of this application, the initial magnetic induction intensity and signal conditioning circuit are configured such that the wound coil converts the initial magnetic induction intensity of the magnetic core into an induced current and transmits it to the signal conditioning circuit.

[0069] In one embodiment of this application, the induced current and differential voltage signal are composed of symmetrically arranged positive and negative voltage conditioning circuits, which convert the AC induced current output by the coil into a differential voltage signal.

[0070] In one embodiment of this application, gain adjustment and ADC sampling thresholding, the operational amplifier and resistor network form a deep negative feedback loop to adjust the gain of the differential voltage signal so that the signal amplitude matches the MCU's ADC input range. The common-mode rejection ratio of the differential circuit is >100dB; In one embodiment of this application, interference cancellation is achieved by matching the resistance parameters of the negative feedback loop with the hysteresis loss coefficient and temperature drift coefficient of the soft magnetic alloy core, thus forming a passive interference cancellation mechanism.

[0071] The beneficial effects of the above scheme are as follows: This application enables real-time, high-precision detection of leakage current with a wide range of 0.01mA-100mA, even in environments with strong electromagnetic interference.

[0072] Example 7: The receiver includes a second power management system, a second communication module, and a data display unit; wherein the second power management system is electrically connected to the second communication module and the data display unit respectively; The second communication module is used to capture the target electromagnetic waves and convert them into visual data; The data display unit is used to display visualized data via an LCD screen; the visualized data includes measured values, AC, battery voltage, stored data, and marker symbols.

[0073] In one embodiment of this application, the second power management system also functions to regulate the battery voltage to the 3.3V required by the circuit for powering the chip and microcontroller. The target electromagnetic wave is the electromagnetic wave emitted by the 433MHz communication module.

[0074] In one embodiment of this application, the main control chip is also an STM32 series low-power MCU. The chip has a built-in high-precision ADC with powerful performance. Through the wireless communication module, the receiving end captures the electromagnetic wave signal emitted by the transmitting end, converts it into an electrical signal, amplifies and filters it, and then performs demodulation processing, etc.

[0075] In one embodiment of this application, the data display shows the received information through an LCD screen, including the display of measured values, AC symbol display, low battery voltage display, stored data display, and other special symbols.

[0076] In one specific embodiment of this application, after the device is powered on, it first initializes the system, and then configures and initializes the relevant peripherals. After initialization, it enters the main loop, in which it repeatedly executes subroutines such as ADC sampling, display refresh, wireless transmission, button operation, low-power management, data processing and fault diagnosis, data storage, and communication. The MCU triggers the AD conversion periodically, filters the collected current data, calculates temperature compensation, and generates a standard data format. According to the preset transmission mode, the data is packaged and transmitted through the corresponding wireless module, while simultaneously receiving terminal instructions, such as adjusting the transmission interval and setting the overcurrent threshold.

[0077] The beneficial effects of the above scheme are as follows: This application can optimize the receiver's user experience, providing more comprehensive information display and longer battery life.

[0078] Example 8: The second communication module of the receiver and the data display unit form a data verification closed loop: After demodulating the target electromagnetic wave signal, the second communication module compares the demodulated data with a preset checksum generation algorithm through the main control MCU; the checksum generation algorithm is dynamically adjusted based on the byte length of the demodulated data and the carrier frequency characteristics of the wireless transmission. When the comparison results match, the main control MCU triggers the backlight module of the LCD display to flash at a preset frequency; among which, The flicker frequency is positively correlated with the rate of change of the effective value of leakage current in the demodulated data. When the data display unit displays the stored data, it simultaneously calls the check code generation algorithm to perform secondary verification on the historical stored data, so as to mark the abnormal data segment on the LCD screen with special symbols.

[0079] In one specific embodiment of this application, the communication module and the display unit work together to form a closed loop, where the demodulated data verification of the second communication module and the feedback control of the display unit ensure the reliability of data transmission and storage through algorithm comparison and visual feedback. After the communication module demodulates the data, the main control MCU generates a checksum in real time and compares it with the preset algorithm result. If the comparison passes, the display unit is triggered to provide feedback, adjusting the checksum generation parameters based on the data byte length and the characteristics of the 433MHz carrier frequency to adapt to wireless channel fluctuations.

[0080] In one specific embodiment of this application, under the coordination of byte length and carrier frequency characteristics, the algorithm for dynamically adjusting the check code generation rule is based on the real-time characteristics of the byte length and carrier frequency of the demodulated data. For example, when N>32 bytes, CRC32 is used, and when N≤32 bytes, CRC16 is used. At the same time, the check code threshold is corrected according to the carrier frequency drift.

[0081] In one specific embodiment of this application, the flicker frequency of this application is positively correlated with the rate of change of leakage current, and the flicker frequency of the LCD backlight module increases linearly with the rate of change of the effective value of leakage current in the demodulated data.

[0082] In one specific embodiment of this application, historical data undergoes secondary verification and anomaly marking. The data display unit calls a check code generation algorithm to re-verify the stored historical data. If the verification fails, the corresponding data segment is marked with a special symbol on the LCD.

[0083] The beneficial effects of the above scheme are as follows: This application utilizes a dynamic verification algorithm and the characteristics of a 433MHz carrier wave to adapt to the special signal attenuation under high-voltage environments. It also determines the presence of safety warnings by analyzing backlight flicker frequency and leakage current change rate. Finally, it ensures the reliability of the output data through secondary verification using historical data and real-time anomaly marking.

[0084] Example 9: The receiver is also used for: The target characteristic waveform of the leakage current signal is determined by a sampling frequency not lower than a preset frequency; wherein, the preset frequency is the target sampling frequency that covers the high-frequency peak of the leakage current signal. The target waveform features are decomposed into multiple intrinsic mode function components through multimodal decomposition, and the intrinsic mode function components are normalized and calculated to generate multiple feature vectors. Multiple feature vectors are passed through a trained leakage current classifier and optimized using a sparrow search algorithm to output leakage current identification factors. Based on the leakage current identification factors, the corresponding protection trigger items are matched; among them, the protection trigger items and the leakage current identification factors have a synchronous triggering mechanism.

[0085] In one specific embodiment of this application, the preset frequency covers high-frequency peak values, and the sampling frequency is not less than twice the high-frequency peak value of the leakage current signal. The target feature waveform identifies the waveform status corresponding to the factors characterizing the leakage state in the leakage current signal.

[0086] In one specific embodiment of this application, the intrinsic mode function (IMF) components and eigenvectors are decomposed into multiple stationary IMFs using empirical mode decomposition (EMD) or variational mode decomposition (VMD). Then, Z-score normalization is used to convert the IMF components into dimensionless eigenvectors. This is used to decompose complex waveforms into frequency-domain separable basic components, enhancing the comparability of features.

[0087] In one specific embodiment of this application, a leakage current classifier optimized by the sparrow search algorithm, a machine learning-based classifier, optimizes model parameters through the sparrow search algorithm to identify leakage current types, thereby improving identification accuracy and speed. Leakage current identification factors are those characterizing the causes of leakage current.

[0088] In one specific embodiment of this application, leakage current factors and protection triggers are automatically matched with preset protection measures based on leakage current identification factors.

[0089] The beneficial effects of the above scheme are as follows: This application dynamically determines the sampling rate through spectral characteristics, locates faults through a sparrow search algorithm, and synchronously triggers protection triggers in the relay protection process, i.e., leakage protection measures, to achieve a highly sensitive protection circuit.

[0090] Example 10: The schematic diagram of the amplifier circuit is as follows Figure 9 As shown, the first-stage amplifier circuit consists of a positive voltage conditioning circuit and a negative voltage conditioning circuit arranged in a symmetrical structure. The negative voltage conditioning circuit includes an operational amplifier, a clamping diode, and a resistor network. The clamping diode is connected in reverse series between the output terminal of the operational amplifier and the ground terminal. The input terminal of the operational amplifier is electrically connected to the resistor network. When the absolute value of the input voltage is less than 1.75V, the amplification factor of the first-stage amplifier circuit is -1.4491; When the absolute value of the input voltage is greater than 1.75V, the amplification factor of the first-stage amplifier circuit switches to -0.1423; The second-stage amplifier circuit is a second-order Sallen-Key low-pass filter circuit composed of operational amplifiers.

[0091] In one specific embodiment of this application, the first-stage symmetrical amplifier circuit, with its positive and negative voltage conditioning circuits symmetrically arranged, processes the positive and negative half-cycles of the input signal respectively, forming a differential amplifier structure. Based on differential amplification technology, the symmetrical structure suppresses common-mode noise and improves the common-mode rejection ratio; the positive and negative voltage conditioning circuits respectively employ operational amplifiers and resistor networks with the same parameters to ensure the symmetry of signal processing and avoid DC offset.

[0092] In one specific embodiment of this application, a clamping diode and a resistor network are used. The clamping diode is connected in reverse series at the output terminal of the operational amplifier. When the output voltage exceeds the reverse breakdown voltage of the diode, it conducts and clamps the voltage to a safe range. The resistor network forms a feedback loop and sets the initial amplification factor.

[0093] In one specific embodiment of this application, the dynamic amplification factor switching automatically adjusts the amplification factor based on the absolute value of the input voltage, providing high gain amplification for weak signals and low gain amplification for strong signals, thus achieving wide range coverage. Gain switching is triggered by the conduction state of a clamping diode; the equivalent resistance changes when the diode is on, altering the parameters of the feedback network. The second-stage low-pass filter circuit, composed of an operational amplifier, resistors, and capacitors, forms a first-order low-pass filter to further suppress high-frequency noise introduced by the first-stage amplifier circuit.

[0094] The low-pass filter circuit, resistor network, positive voltage conditioning circuit, and negative voltage conditioning circuit all use common, conventional circuits without any modifications to existing general-purpose circuits.

[0095] The beneficial effects of the above scheme are as follows: This application achieves dead-zone-free government signal processing through a symmetrical structure and clamping diodes. By setting a voltage threshold of 1.75V and the amplification factor, the switching point is precisely controlled, avoiding the resolution loss of traditional integer gain. The nonlinear gain of the first-stage amplifier circuit and the filtering of the second-stage amplifier circuit eliminate high-frequency glitches generated during switching, ensuring signal continuity. The two amplifier circuits work together to improve switching accuracy and response speed.

[0096] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A wide-range wireless high-voltage leakage current detection system, characterized in that, include: A main unit detector is fixedly installed on an insulating pole; the main unit detector is equipped with a front-end sensing module. The front-end sensing module includes a data acquisition unit and a circuit unit; among which, The acquisition unit includes a square magnetic circuit bayonet structure for clamping the high-voltage line and acquiring leakage current signals, as well as a built-in soft magnetic alloy core and wound coil. The circuit section includes a first-stage amplifier circuit and a second-stage amplifier circuit. The first-stage amplifier circuit automatically switches the gain mode according to the amplitude of the input signal; wherein, When the leakage current signal is at the first range, the first-stage amplifier circuit starts the high-gain small-signal mode. When the leakage current signal is in the second range, the first-stage amplifier circuit and the second-stage amplifier circuit activate the low-gain large-signal mode. The maximum value of the first range is equal to the minimum value of the second range; The receiver communicates wirelessly with the host detector and is used to receive leakage current signals.

2. The wide-range wireless high-voltage leakage current detection system as described in claim 1, characterized in that, The square magnetic circuit bayonet structure includes a main support frame, support arms, a square magnetic circuit bayonet, and a tension spring arranged symmetrically at the top and bottom; wherein... The main support frame is made of high-strength insulating material, with a strip magnetic core and wound coil inserted and fixed inside. The length of a single main support frame is 160cm. The square magnetic circuit bayonet is fixed to the lower main body bracket by screws, the lower end of the bracket arm is connected to the square magnetic circuit bayonet by a rotating shaft, and the contact surface between the upper extension and the upper main body bracket is highly polished. The two ends of the tension spring are connected to the square magnetic circuit bayonet and the support arm respectively. When the bayonet is closed by the spring tension, the air gap of the magnetic circuit is ≤0.1mm.

3. The wide-range wireless high-voltage leakage current detection system as described in claim 2, characterized in that, The square magnetic circuit bayonet structure also includes an insulating support rod, which forms a composite mechanical structure with the main support frame. The insulating support rods are made of the same high-strength insulating material as the main support and are arranged diagonally along the square magnetic circuit bayonet. The two ends of the intersecting insulating support rods are respectively connected to the upper and lower main supports through mortise and tenon structures. The contact surface of the mortise and tenon structure is coplanar with the polished contact surface of the support arm. When the tension of the tension spring is transmitted to the main support through the support arm, the deformation direction of the composite mechanical structure is consistent with the closing direction of the magnetic circuit air gap. Moreover, the elastic modulus of the insulating support rod is matched with the thermal expansion coefficient of the main support, so that the magnetic circuit air gap is in the preset stable range when the ambient temperature changes from -20℃ to 100℃.

4. The wide-range wireless high-voltage leakage current detection system as described in claim 1, characterized in that, The soft magnetic alloy core is made of a high-permeability soft magnetic precision alloy material to determine the first magnetic induction intensity threshold. A soft magnetic alloy core is uniformly wound with an enameled wire coil to increase the first magnetic induction intensity threshold to a second magnetic induction intensity threshold; wherein the second magnetic induction intensity threshold is greater than the first magnetic induction intensity threshold.

5. The wide-range wireless high-voltage leakage current detection system as described in claim 1, characterized in that, The host detector also includes a first power management system, a signal conditioning circuit, a main control MCU, and a first communication module, wherein the first power management system, the signal conditioning circuit, and the first communication module are electrically connected to the main control MCU. The signal conditioning circuit is electrically connected to the front-end sensing module and converts the induced current of the square magnetic circuit bayonet into a target voltage that conforms to the sampling standard of the main control MCU. The first communication module is used to encode and modulate the target voltage into a 433MHz carrier wave and convert it into a target electromagnetic wave for transmission to the receiver.

6. The wide-range wireless high-voltage leakage current detection system as described in claim 5, characterized in that, The first-stage amplifier circuit and the soft magnetic alloy core form a cooperative induction structure: The soft magnetic alloy core converts the weak leakage current of the cable under test into an initial magnetic induction intensity through its high magnetic permeability. The initial magnetic flux density is coupled to the signal conditioning circuit via a wound coil; The symmetrical structure of the first-stage amplifier circuit and the positive and negative voltage conditioning circuit convert the induced current corresponding to the initial magnetic induction intensity into a differential voltage signal. The differential voltage signal is gain-adjusted through a negative feedback loop consisting of an operational amplifier and a resistor network, which improves the signal-to-noise ratio of the differential voltage signal to the sampling threshold range of the ADC of the main control MCU. Furthermore, the resistor network of the negative feedback loop matches the hysteresis loss and temperature drift of the soft magnetic alloy core, enabling the induced signal to achieve the target accuracy.

7. The wide-range wireless high-voltage leakage current detection system as described in claim 1, characterized in that, The receiver includes a second power management system, a second communication module, and a data display unit; wherein the second power management system is electrically connected to the second communication module and the data display unit respectively; The second communication module is used to capture the target electromagnetic waves and convert them into visual data; The data display unit is used to display visualized data via an LCD screen; the visualized data includes measured values, AC, battery voltage, stored data, and marker symbols.

8. The wide-range wireless high-voltage leakage current detection system as described in claim 7, characterized in that, The receiver's second communication module and the data display unit form a data verification closed loop: After demodulating the target electromagnetic wave signal, the second communication module compares the demodulated data with a preset checksum generation algorithm through the main control MCU; the checksum generation algorithm is dynamically adjusted based on the byte length of the demodulated data and the carrier frequency characteristics of the wireless transmission. When the comparison results match, the main control MCU triggers the backlight module of the LCD display to flash at a preset frequency; among which, The flicker frequency is positively correlated with the rate of change of the effective value of leakage current in the demodulated data. When the data display unit displays the stored data, it simultaneously calls the check code generation algorithm to perform secondary verification on the historical stored data, so as to mark the abnormal data segment on the LCD screen with special symbols.

9. The wide-range wireless high-voltage leakage current detection system as described in claim 1, characterized in that, The receiver is also used for: The target characteristic waveform of the leakage current signal is determined by a sampling frequency not lower than a preset frequency; wherein, the preset frequency is the target sampling frequency that covers the high-frequency peak of the leakage current signal. The target waveform features are decomposed into multiple intrinsic mode function components through multimodal decomposition, and the intrinsic mode function components are normalized and calculated to generate multiple feature vectors. Multiple feature vectors are passed through a trained leakage current classifier and optimized using a sparrow search algorithm to output leakage current identification factors. Based on the leakage current identification factors, the corresponding protection trigger items are matched; among them, the protection trigger items and the leakage current factors have a synchronous triggering mechanism.

10. The wide-range wireless high-voltage leakage current detection system as described in claim 1, characterized in that, The first-stage amplifier circuit consists of a positive voltage conditioning circuit and a negative voltage conditioning circuit arranged in a symmetrical structure. The negative voltage conditioning circuit includes an operational amplifier, a clamping diode, and a resistor network. The clamping diode is connected in reverse series between the output terminal of the operational amplifier and the ground terminal. The input terminal of the operational amplifier is electrically connected to the resistor network. When the absolute value of the input voltage is less than 1.75V, the amplification factor of the first-stage amplifier circuit is -1.4491; When the absolute value of the input voltage is greater than 1.75V, the amplification factor of the first-stage amplifier circuit switches to -0.1423; The second-stage amplifier circuit is a second-order Sallen-Key low-pass filter circuit composed of operational amplifiers.

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