Cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control

Abstract

The present application belongs to the field of cable non-destructive testing technology, and specifically discloses a cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control, comprising: a magnetizer combination, a coil and a magnetic field control plate, the magnetizer combination comprising a plurality of magnetizers uniformly distributed along the circumferential direction of the cable surface, the magnetic poles on the same side of different magnetizers having the same magnetic properties, the coil circumferentially wound in the middle of the two magnetic poles of each magnetizer on the cable surface, the magnetic field control plate circumferentially wound on the cable surface, and configured to control the static bias magnetic field applied by the magnetizer combination in the cable, and / or, control the dynamic magnetic field generated by the coil after an alternating excitation current is passed through, thereby enhancing the cable magnetostrictive guided wave detection signal. The present application achieves the enhancement of the guided wave detection signal by adding a magnetic field control plate to control the static bias magnetic field applied by the magnetizer combination in the cable, and / or, control the dynamic magnetic field generated by the coil after an alternating excitation current is passed through.

Description

Technical Field

[0001] The present application belongs to the technical field of cable non-destructive testing, and more specifically, relates to a cable magnetostrictive guided wave detection signal enhancement device based on magnetic field regulation. Background Art

[0002] Cables, with their advantages of high strength, lightweight, durability, and ease of operation, are widely used in modern engineering structures such as suspension bridges and cable-stayed bridges. As key load-bearing components of bridges, they are susceptible to fatigue-induced wire breakage due to the immense dead and live loads, alternating stresses, and vibrations they endure. Furthermore, due to stress and the ineffectiveness of anti-corrosion measures, internal corrosion defects are prone to occur in cables. Defects such as wire breakage and corrosion pose a significant threat to the overall structural safety and service life of bridges.

[0003] Guided waves offer the advantage of inspecting a specific area with single-point excitation, eliminating the need to move the sensor and enabling inspection within anchored areas. Magnetostrictive longitudinal guided waves are widely used in cable inspection due to their high liftoff and simple sensor installation. Currently, most magnetostrictive guided wave enhancement technologies utilize contact excitation or increased excitation signal strength. Contact excitation is not suitable for cables with non-metallic outer sheaths, while increasing excitation signal strength is limited by hardware circuitry and has limited impact on improving guided wave signal amplitude.

[0004] Compared to testing objects like steel plates and pipes, cable magnetostrictive longitudinal guided wave testing has a larger loading cross-sectional area. Under the same excitation conditions, the guided wave signal intensity generated by the cable is relatively low. Furthermore, the cable's 5-15mm outer non-metallic sheath creates a significant separation distance between the coil and the metal material loading the guided wave, further weakening the guided wave signal strength. Given a constant excitation guided wave signal strength, the guided wave's detection capability decreases for defects farther from the sensor and less severe due to signal propagation attenuation and reflected energy loss. This severely limits the ability of magnetostrictive longitudinal guided wave testing to detect cable defects. Summary of the Invention

[0005] In response to the defects of related technologies, the embodiments of the present application provide a cable magnetostrictive guided wave detection signal enhancement device based on magnetic field regulation, which aims to solve the problem of low cable magnetostrictive guided wave detection signal intensity.

[0006] In a first aspect, an embodiment of the present application provides a cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control, comprising: a magnetizer assembly, a coil, and a magnetic field control plate;

[0007] The magnetizer combination includes a plurality of magnetizers uniformly distributed along the circumference of the cable surface, and the magnetic poles on the same side of different magnetizers have the same magnetic properties;

[0008] The coil is wound circumferentially between the two magnetic poles of each magnetizer on the cable surface;

[0009] The magnetic field control plate is circumferentially wound around the surface of the cable and is configured to control the static bias magnetic field applied by the magnetizer assembly in the cable and / or the dynamic magnetic field generated by the coil after an alternating excitation current is passed through it, thereby enhancing the cable's magnetostrictive guided wave detection signal.

[0010] In some embodiments, the magnetic field control plate includes a bias magnetic field control plate assembly, the bias magnetic field control plate assembly including two bias magnetic field control plates, each circumferentially wound around two magnetic poles of each magnetizer on the cable surface, each magnetizer being adsorbed on the two bias magnetic field control plates;

[0011] The bias magnetic field regulating plate assembly is configured to regulate the static bias magnetic field applied by the magnetizer assembly in the cable, thereby enhancing the cable magnetostrictive guided wave detection signal.

[0012] In some embodiments, the magnetic field control plate includes a dynamic magnetic field control plate, which is circumferentially wound on the surface of the coil;

[0013] The dynamic magnetic field control board is configured to control the dynamic magnetic field generated by the coil after the alternating excitation current is passed through the coil, thereby enhancing the cable magnetostrictive guided wave detection signal.

[0014] In some embodiments, the magnetic field control plate includes a bias magnetic field control plate assembly and a dynamic magnetic field control plate; the bias magnetic field control plate assembly includes two bias magnetic field control plates, which are circumferentially wound around the two magnetic poles of each magnetizer on the cable surface, and each magnetizer is adsorbed on the two bias magnetic field control plates; the dynamic magnetic field control plate is wound around the surface of the coil;

[0015] The bias magnetic field control board assembly is configured to control the static bias magnetic field applied by the magnetizer assembly in the cable, and the dynamic magnetic field control board is configured to control the dynamic magnetic field generated by the coil after an alternating excitation current is passed through the coil, thereby enhancing the cable's magnetostrictive guided wave detection signal.

[0016] In some embodiments, the bias magnetic field control board is configured to improve the magnetostrictive efficiency of the cable magnetostrictive guided wave sensor at a bias magnetic field operating point.

[0017] In some embodiments, the dynamic magnetic field modulation plate is configured to enhance the axial dynamic magnetic field inside the cable.

[0018] In some embodiments, the bias magnetic field control plate is made of a high magnetic permeability metal material, and its width is greater than or equal to the length of the magnetic pole of the magnetizer.

[0019] In some embodiments, the bias magnetic field control plate increases the attraction between the magnetizer assembly and the cable, reduces the repulsion between the magnetic poles of each magnetizer, and increases the number of magnetizers that can be included in the magnetizer assembly.

[0020] In some embodiments, the dynamic magnetic field control plate is made of a high magnetic permeability metal material, and its width is greater than or equal to the width of the coil.

[0021] In some embodiments, the width of the dynamic magnetic field control plate ranges from 1 to 1.5 times the width of the coil.

[0022] The cable magnetostrictive guided wave detection signal enhancement device based on magnetic field regulation provided in the embodiments of the present application, by adding a magnetic field regulation plate, regulates the static bias magnetic field applied by the magnetizer assembly in the cable, so that the cable magnetostrictive guided wave sensor operates at a bias magnetic field operating point with higher magnetostrictive efficiency; and / or regulates the dynamic magnetic field generated by the coil after the alternating excitation current is passed, thereby enhancing the axial dynamic magnetic field inside the cable, thereby achieving enhancement of the guided wave detection signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in this application or related technologies, the following is a brief introduction to the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0024] Figure 1 It is a structural diagram of a magnetizer provided by related technology;

[0025] Figure 2 It is a structural diagram of a cable magnetostrictive longitudinal waveguide sensor provided by related technology;

[0026] Figure 3 This is a schematic diagram of the arrangement of a cable magnetostrictive longitudinal waveguide sensor provided by the related art;

[0027] Figure 4 This is a schematic diagram of the principle of generating a cable magnetostrictive longitudinal guided wave detection signal provided by the related art;

[0028] Figure 5 It is a schematic diagram of the magnetostrictive curve of the cable provided by the related art;

[0029] Figure 6 1 is a flow chart of a method for enhancing cable magnetostrictive guided wave detection signals based on magnetic field control provided in an embodiment of the present application;

[0030] Figure 7Schematic diagram of the structure of a cable magnetostrictive longitudinal waveguide sensor based on magnetic field control provided in an embodiment of the present application;

[0031] Figure 8 Schematic diagram of a conventional cable magnetostrictive guided wave detection signal provided by an embodiment of the present application;

[0032] Figure 9 Schematic diagram of cable magnetostrictive guided wave detection signal based on magnetic field control provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0034] Figure 1 It is a structural diagram of the magnetizer provided by the related technology, such as Figure 1 As shown, the magnetizer consists of an armature and two permanent magnet poles. The magnetizer uses the principle of electromagnetic induction to convert non-magnetic materials into magnetic materials through the magnetic field generated by current.

[0035] Figure 2 This is a structural diagram of a cable magnetostrictive longitudinal waveguide sensor provided by related technology, such as Figure 2 As shown, a conventional cable magnetostrictive longitudinal guided wave sensor has multiple identical magnetizers evenly spaced circumferentially along the cable surface. The poles on the same side of different magnetizers have the same magnetic properties. A coil is wound circumferentially between the poles of each magnetizer. The cable magnetostrictive longitudinal guided wave sensor includes an excitation sensor and a receiving sensor, with the corresponding coils being the excitation coil and the receiving coil, respectively.

[0036] Figure 3 This is a schematic diagram of the arrangement of the cable magnetostrictive longitudinal waveguide sensor provided by the related technology. Figure 3 The positional relationship shown arranges the excitation sensor and the receiving sensor on the surface of the cable, with a certain distance between them. The magnetization directions of the excitation sensor and the receiving sensor are consistent, and the excitation sensor is a certain distance away from the left end face of the cable. The sinusoidal AC excitation signal is power-amplified and then passed into the coil. The excited guided wave signal propagates in the cable and is received by the receiving sensor to obtain the cable magnetostrictive longitudinal guided wave detection signal.

[0037] Figure 4 This is a schematic diagram of the principle of generating cable magnetostrictive longitudinal guided wave detection signals provided by related technologies. Figure 5 This is a schematic diagram of the magnetostrictive curve of the cable provided by the relevant technology, the horizontal axis is the magnetic field intensity, and the vertical axis is the magnetostrictive strain. Figure 4and Figure 5 Multiple magnetizers magnetize the cable within a specific area, providing a bias magnetic field Hs oriented axially along the cable. When the cable is subjected to a certain magnetic field strength H, a certain strain will occur. The bias magnetic field Hs causes the cable to be in a static magnetostrictive state at a certain level. When a sinusoidal AC excitation signal is applied to a coil wound circumferentially between the two poles of the cable surface magnetizer, a sinusoidally varying dynamic magnetic field Hd is excited along the cable axis. This dynamic magnetic field Hd is much smaller than the bias magnetic field Hs, resulting in a total combined magnetic field H = Hs + Hd, specifically a sinusoidal magnetic field that fluctuates around Hs.

[0038] The sinusoidal magnetic field induces a sinusoidal magnetostrictive strain in the cable material. Because magnetostrictive strain is non-directional, if Hs = 0, the frequency of the generated sinusoidal strain will be twice the excitation signal, so the baseline Hs cannot be 0. The sinusoidal strain propagates through the cable as a mechanical wave. Based on the inverse process described above, the receiving sensor picks up the propagated guided wave signal, which carries the corresponding cable structural characteristics. This information is then used to determine the cable's condition.

[0039] However, compared to inspection targets like steel plates and pipes, cable magnetostrictive longitudinal guided wave testing has a larger loading cross-sectional area. Under the same excitation conditions, the guided wave signal intensity generated by the cable is relatively low. Furthermore, the cable's 5-15mm outer non-metallic sheath creates a significant separation distance between the coil and the metal material loading the guided wave, further weakening the guided wave signal strength in the cable. Given a constant level of excitation guided wave signal intensity, the guided wave's detection capability decreases for defects farther from the sensor and less severe due to signal propagation attenuation and reflected energy loss. This severely limits the ability of magnetostrictive longitudinal guided wave testing to discern cable defects.

[0040] Based on this, the embodiments of the present application provide a method and device for enhancing cable magnetostrictive guided wave detection signals based on magnetic field control, so as to improve the strength of cable magnetostrictive guided wave detection signals.

[0041] Figure 6 is a flow chart of a cable magnetostrictive guided wave detection signal enhancement method based on magnetic field control provided in an embodiment of the present application, such as Figure 6 As shown, the method includes at least the following steps:

[0042] S601. Regulate the static bias magnetic field applied by the magnetizer assembly in the cable through the magnetic field control board, and / or regulate the dynamic magnetic field generated by the coil after an alternating excitation current is passed through the coil, to obtain an enhanced cable magnetostrictive guided wave detection signal.

[0043] Specifically, the device is implemented by a cable magnetostrictive guided wave detection signal enhancement device based on magnetic field regulation, which can also be called a cable magnetostrictive guided wave sensor based on magnetic field regulation. Figure 2 The conventional cable magnetostrictive longitudinal waveguide sensor shown in the figure, however, utilizes a magnetic field control cable magnetostrictive waveguide sensor, as provided in the embodiments of the present application. In addition to the magnetizer assembly and coil, the magnetic field control plate is also included. The plate is wrapped circumferentially around the cable surface. This plate can control the material's magnetic properties by applying an external magnetic field. Several specific aspects of the magnetic field control plate are described below.

[0044] Case 1: Only the bias magnetic field control board is used.

[0045] In some embodiments, the magnetic field control plate includes a bias magnetic field control plate assembly, which includes two bias magnetic field control plates, each circumferentially wrapped around the two magnetic poles of each magnetizer on the cable surface. Each magnetizer is attached to the two bias magnetic field control plates. S601 specifically includes: controlling the static bias magnetic field applied by the magnetizer assembly in the cable via the bias magnetic field control plate assembly to obtain an enhanced cable magnetostrictive guided wave detection signal.

[0046] The bias magnetic field control board is configured to control the static bias magnetic field applied by the magnetizer assembly in the cable, so that the sensor operates at a bias magnetic field operating point with higher magnetostrictive efficiency.

[0047] Combine Figure 5 It can be seen that the change in magnetostrictive strain with magnetic field is not linear; the greater the slope of the curve, the higher the efficiency of generating magnetostrictive strain. However, when multiple magnetizers are arranged in the same direction, there will be a very strong repulsive force between the like poles of the magnetizers. The number of magnetizers that can be installed on the cable is limited by the repulsive force between the poles. As a result, the detection range of the magnetizer combination cannot cover the circumference of the cable, or it cannot reach the optimal magnetostrictive efficiency bias magnetic field operating point.

[0048] Optionally, the bias magnetic field control plate is made of a metal material with high magnetic permeability and is circumferentially wound around the two magnetic poles of each magnetizer on the cable surface, thereby increasing the adsorption force between the magnetizer and the cable and reducing the repulsion between the magnetizers. This increases the number of magnetizers that can be included in the magnetizer combination, so that the detection range of the magnetizer combination can cover the circumference of the cable, and the optimal number of magnetizers can be found. This allows for more flexible control of the size of the static bias magnetic field, allowing the cable magnetostrictive guided wave sensor to operate at a bias magnetic field operating point with higher magnetostrictive efficiency, thereby achieving the effect of increasing the guided wave detection signal.

[0049] Optionally, the bias magnetic field control plate needs to be circumferentially wound on the surface of the cable, so the thickness should not be too thick; at the same time, since it is necessary to provide sufficient adsorption force between the magnetizer and the cable and reduce the repulsion between the same magnetic poles of the magnetizer, the thickness should not be too thin, and is preferably 0.1-2 mm.

[0050] Optionally, since the bias magnetic field control plate is placed below the magnetizer's poles, its width should be greater than or equal to the magnetizer's pole length to generate sufficient attraction. Furthermore, a wider bias magnetic field control plate can interfere with the dynamic magnetic field generated by the coil. Therefore, its width is limited to [pole length minus pole length + 10 mm].

[0051] Case 2: Only the dynamic magnetic field control board is used.

[0052] In some embodiments, the magnetic field control plate includes a dynamic magnetic field control plate, which is wound around the surface of the coil. S601 specifically includes: controlling, by the dynamic magnetic field control plate, the dynamic magnetic field generated by the coil after an alternating excitation current is applied thereto, thereby obtaining an enhanced cable magnetostrictive guided wave detection signal.

[0053] The dynamic magnetic field control board is configured to control the dynamic magnetic field generated by the coil after the alternating excitation current is passed through it, and to gather the dynamic magnetic field that is diffusely distributed in space.

[0054] Combine Figure 5 It can be seen that the peak-to-peak value of the generated magnetostrictive sinusoidal strain is not only related to the slope of the bias magnetic field at the operating point, but also to the fluctuation amplitude of the dynamic magnetic field. Optionally, a dynamic magnetic field control plate made of a high-permeability metal material can be wound around the coil surface to act as a magnetic field concentrator. By altering the dynamic magnetic field distribution around the coil, the spatially diffuse dynamic magnetic field can be more closely concentrated within the cable, enhancing the axial dynamic magnetic field within the cable and thus enhancing the guided wave detection signal.

[0055] Optionally, the dynamic magnetic field control plate needs to be wound along the circumference of the cable, so the thickness should not be too thick; at the same time, since a certain control effect on the dynamic magnetic field is required, the thickness should not be too thin, preferably 0.1-2 mm.

[0056] Optionally, a dynamic magnetic field control plate is wrapped around the surface of the coil to control the magnetic field generated by the coil. Therefore, its width should be greater than the width of the coil. Furthermore, because the dynamic magnetic field control plate and the coil are placed together between the two poles of the magnetizer, space is limited. To minimize its impact on the static bias magnetic field, the width of the dynamic magnetic field control plate should not be too large. Optionally, the width of the dynamic magnetic field control plate ranges from 1 to 1.5 times the width of the coil.

[0057] Optionally, since the bias magnetic field control plate is placed below the magnetizer's poles, its width should be greater than or equal to the magnetizer's pole length to generate sufficient attraction. Furthermore, a wider bias magnetic field control plate can interfere with the dynamic magnetic field generated by the coil. Therefore, its width is limited to [pole length minus pole length + 10 mm].

[0058] Case 3: Using the bias magnetic field control board and the dynamic magnetic field control board at the same time.

[0059] Figure 7 is a structural diagram of a cable magnetostrictive longitudinal waveguide sensor based on magnetic field control provided in an embodiment of the present application, such as Figure 7 As shown, by using the bias magnetic field control board and the dynamic magnetic field control board at the same time, the cable magnetostrictive waveguide sensor can be operated at a bias magnetic field working point with higher magnetostrictive efficiency, and the axial dynamic magnetic field inside the cable can be enhanced, thereby achieving a better waveguide detection signal enhancement effect.

[0060] In the excitation sensor part, the appropriate bias magnetic field operating point interacts with the enhanced dynamic magnetic field to stimulate an enhanced magnetostrictive longitudinal guided wave signal in the cable. The receiving end sensor uses the same device to further enhance the received guided wave signal.

[0061] The technical solution provided in the embodiment of the present application is further illustrated below through a specific example. Figure 8 Schematic diagram of a conventional cable magnetostrictive guided wave detection signal provided by an embodiment of the present application. Figure 9 This is a schematic diagram of a cable magnetostrictive guided wave detection signal based on magnetic field control provided in an embodiment of the present application. The horizontal axis represents time (unit: ms) and the vertical axis represents amplitude (unit: V).

[0062] For a 10-strand, 7-core external cable with an outer diameter of 159 mm and a length of 12 m, before the cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control proposed in the embodiment of the present application is adopted, due to the repulsive force between the same-name magnetic poles of the magnetizers, a maximum of 4 magnetizers can be arranged in the circumferential direction of the cable specimen (refer to Figure 2 ).according to Figure 3 The cable magnetostrictive longitudinal guided wave sensor is arranged on the cable surface in the position relationship shown. The distance between the excitation sensor and the receiving sensor is 2m. The magnetization directions of the excitation sensor and the receiving sensor are consistent. The excitation sensor is 2.5m away from the left end face of the cable. A sinusoidal AC excitation signal with a frequency of 10kHz, a period of 2, and an amplitude of 1V is amplified and then passed into the coil. The excited guided wave signal propagates in the cable and is received by the receiving sensor. The guided wave detection signal is shown in FIG. Figure 8 shown.

[0063] refer to Figure 7Two bias magnetic field control plates with a width of 80 mm are circumferentially wrapped around the surface of the cable specimen and fastened with auxiliary tape. The spacing between the two bias magnetic field control plates is 200 mm, and the magnetizer combination includes 7 magnetizers. In the middle position of the two magnetic poles of the magnetizer, a DuPont coil with a width of 50 mm is circumferentially wrapped around the surface of the cable specimen, and then a circle of dynamic magnetic field control plate with the same width is wrapped around the coil and fixed with an auxiliary tape.

[0064] Also using Figure 3 The cable magnetostrictive longitudinal waveguide sensor is placed on the cable surface according to the actual position relationship. A sinusoidal AC excitation signal with a frequency of 10kHz, a period of 2, and an amplitude of 1V is used. After power amplification, it is passed into the excitation coil. The dynamic magnetic field generated is regulated by the dynamic magnetic field control board, so that the dynamic magnetic field inside the cable specimen is enhanced. The enhanced dynamic magnetic field works together with the bias magnetic field working point with higher magnetostrictive efficiency to stimulate an intensity-enhanced waveguide detection signal. After propagation and reflection, the enhanced waveguide is received by the receiving coil of the receiving sensor. The bias magnetic field control board and the dynamic magnetic field control board of the receiving sensor further enhance the receiving efficiency of the waveguide detection signal, thereby further enhancing the final obtained waveguide detection signal, such as Figure 9 shown.

[0065] from Figure 8 and Figure 9 It can be seen that after the magnetic field control board is used, the pass signal, the near-end reflected wave signal, and the far-end reflected wave signal are all significantly enhanced. Before the magnetic field control is applied, the far-end reflected wave signal is too weak to be recognized. This application is of great significance for improving the defect detection capability and resolution of magnetostrictive longitudinal waveguide cables.

[0066] It is easy for those skilled in the art to understand that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control, comprising: Magnetizer assembly, coil and magnetic field control board; The magnetizer assembly comprises a plurality of magnetizers uniformly distributed along the circumference of the cable surface, and the magnetic poles on the same side of different magnetizers have the same magnetic properties; The coil is circumferentially wound around the middle of the two magnetic poles of each magnetizer on the cable surface; The magnetic field control plate is circumferentially wound on the surface of the cable and is configured to control the static bias magnetic field applied by the magnetizer assembly in the cable and to control the dynamic magnetic field generated by the coil after an alternating excitation current is passed through the coil, thereby enhancing the cable's magnetostrictive guided wave detection signal; The magnetic field control plate includes a bias magnetic field control plate assembly and a dynamic magnetic field control plate; the bias magnetic field control plate assembly includes two bias magnetic field control plates, which are circumferentially wound around the two magnetic poles of each magnetizer on the cable surface, and each magnetizer is adsorbed on the two bias magnetic field control plates; The dynamic magnetic field control plate is wound on the surface of the coil; The bias magnetic field control board assembly is configured to control the static bias magnetic field applied by the magnetizer assembly in the cable, and the dynamic magnetic field control board is configured to control the dynamic magnetic field generated by the coil after an alternating excitation current is passed through the coil, thereby enhancing the cable magnetostrictive guided wave detection signal.

2. The cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control according to claim 1 is characterized in that: The bias magnetic field control board is configured to improve the magnetostrictive efficiency of the cable magnetostrictive guided wave sensor at a bias magnetic field operating point.

3. The cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control according to claim 1 is characterized in that: The dynamic magnetic field control plate is configured to enhance the axial dynamic magnetic field inside the cable.

4. The cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control according to claim 1 is characterized in that: The bias magnetic field control plate is made of a metal material with high magnetic permeability, and its width is greater than or equal to the length of the magnetic pole of the magnetizer.

5. The cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control according to claim 1 is characterized in that: The bias magnetic field control plate increases the attraction between the magnetizer assembly and the cable, reduces the repulsion between the magnetic poles of each magnetizer, and increases the number of magnetizers that can be included in the magnetizer assembly.

6. The cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control according to claim 1 is characterized in that: The dynamic magnetic field control plate is made of a high magnetic permeability metal material, and its width is greater than or equal to the width of the coil.

7. The cable magnetostrictive guided wave detection signal enhancement device based on magnetic field control according to claim 1 is characterized in that: The width of the dynamic magnetic field control plate ranges from 1 to 1.5 times the width of the coil.

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