Main cable pulse magnetization broken wire detection system and detection method

Abstract

The invention relates to the technical field of bridge cable nondestructive testing, and discloses a main cable pulse magnetization broken wire detection system and detection method.The broken wire detection system comprises a sensing mechanism, and the sensing mechanism comprises a U-shaped armature; the pair of exciting coils are respectively wound at two free ends of the U-shaped armature, and the pair of exciting coils are used for respectively introducing currents with the same frequency and opposite directions; the detection coil is located in the center of the pair of excitation coils, is flush with the lower end faces of the excitation coils and is used for receiving leakage magnetic field signals formed by breaking joints generated by wire breakage of the parallel steel wires on the outer layer of the main cable; in the process that the excitation coil and the detection coil are arranged on the outer surface of the main cable in parallel at intervals and move in the axial direction of the main cable, when the magnetic flux in the detection coil changes due to the leakage magnetic field signals, the detection coil generates induced voltage. The broken wire detection system and the detection method are safe, lossless, suitable for main cable detection and high in detection efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bridge cable nondestructive testing, and in particular to a main cable pulse magnetization broken wire detection system and a detection method. BACKGROUND

[0002] At present, as the most important load-bearing and force-transmitting component of a suspension bridge, the main cable is in a high stress state for a long time, is subjected to the combined action of dynamic load and complex environment, and after serving for several years, problems such as steel wire fatigue and corrosion occur, which leads to a decrease in the load-carrying capacity of the main cable and a decrease in the service life. In order to avoid bridge accidents, the main cable must be regularly detected and maintained.

[0003] In the related art, the main cable is generally regularly detected and maintained by the open cable visual method. When detecting, the maintenance personnel ride a main cable maintenance vehicle along the main cable to detect by opening the cable. The open cable visual method has high detection precision.

[0004] However, the detection by the open cable visual method needs the maintenance personnel to complete the detection work in the air, and the process is complex, the cost is high, the efficiency is low, the danger coefficient is high, and damage to the main cable is caused.

[0005] Further, in some detection and maintenance of non-main cables, the magnetic nondestructive testing method is often used. The magnetic nondestructive testing method mainly includes two types. One type is to detect the magnetic leakage signal generated by the internal steel wire defects on the surface of the cable, which is referred to as the LF type detection method. The other type is to obtain the metal cross-sectional area damage information caused by corrosion and the like by detecting the change of the internal magnetic flux of the cable, which is referred to as the LMA type detection method. However, both the LF type detection method and the LMA type detection method can only be applied to the detection of non-main cables such as stay cables, and the reasons are as follows. Both the LF type detection method and the LMA type detection method use a permanent magnet as a magnetizing source to provide a stable magnetic field. However, the diameter of the main cable is large, and the magnetization difficulty is significantly increased, and it is difficult to achieve a saturated magnetization state. The diameter of the bridge stay cable is usually small, and a conventional magnetic detection device (such as a magnetic leakage detection device) can achieve uniform magnetization through a smaller magnetizing device, so that an obvious magnetic leakage field is generated at the defect. However, the diameter of the main cable is generally greater than 300 mm, and it is a large-diameter ferromagnetic component, and a stronger magnetization power is required to achieve a saturated magnetization state. The magnetization capacity of the existing magnetic detection device is difficult to cover the large cross section of the main cable, so that the magnetic leakage field signal generated by the internal defects (such as broken wires and corrosion) is weak and cannot be effectively captured.

[0006] In summary, the traditional open cable visual method has a complex process, a high cost, a low efficiency, a high danger coefficient, and causes damage to the main cable. Both the LF type detection method and the LMA type detection method are not applicable to the detection of the main cable. SUMMARY

[0007] The application provides a broken wire detection system and method for main cable pulse magnetization, which is safe, lossless and suitable for main cable detection, and has high detection efficiency.

[0008] In a first aspect, the application provides a broken wire detection system for main cable pulse magnetization, which comprises a sensing mechanism, and the sensing mechanism comprises: a U-shaped armature; a pair of excitation coils, which are wound on two free ends of the U-shaped armature respectively, and are used for inputting currents with the same frequency and opposite directions respectively to magnetize the main cable; a detection coil, which is located in the middle of the pair of excitation coils and is flush with the lower end surface of the excitation coil, and is used for receiving a leakage magnetic field signal formed by a broken joint of the main cable due to broken wire; the pair of excitation coils and the detection coil are arranged in parallel and at intervals on the outer surface of the main cable and move along the axial direction of the main cable, and when the internal magnetic flux of the detection coil changes due to the leakage magnetic field signal, the detection coil generates an induced voltage.

[0009] In combination with the first aspect, in an implementation, when the main cable has a broken joint and the axial line of the broken joint coincides with the axial line of the detection coil, the magnetic field amount in the two axial directions of the detection coil cancels each other, and the state corresponding to the position is zero position.

[0010] In combination with the first aspect, in an implementation, when the sensing mechanism moves through the zero position before and after, the detection coil generates induced voltages with opposite directions in sequence.

[0011] In combination with the first aspect, in an implementation, when the absolute value of the peak value of the induced voltages with opposite directions exceeds a set error threshold value, it is determined that there is a broken joint in the main cable.

[0012] In combination with the first aspect, in an implementation, the output voltage of the detection coil is an induced voltage generated by the leakage magnetic field at the broken joint of the broken wire in the detection coil . ; In the formula, B is a known excitation magnetic field strength; ΔA S is a steel wire fracture area percentage, ΔG W is a broken joint width, ΔL H is a known vertical distance between the detection coil and the main cable; the induced voltage is related to the internal ΔA and ΔG of the main cable.

[0013] In combination with the first aspect, in an implementation, the broken wire detection system further comprises a driving mechanism, the driving mechanism comprising a motion control circuit and a motor, the motion control circuit controlling the motor to rotate and stop, and the motor providing power for the sensing mechanism to move along the axial direction of the main cable.

[0014] In combination with the first aspect, in an implementation, the broken wire detection system further comprises a remote communication module, a signal processing module and a computer; the signal processing module is relatively fixed to the sensing mechanism and moves synchronously with the sensing mechanism; the signal processing module filters and amplifies the induced voltage signal transmitted by the sensing mechanism; and the remote communication module establishes communication between the computer and the driving mechanism and the signal processing module.

[0015] In the second aspect, the embodiments of the present application provide a detection method based on the above broken wire detection system, comprising the following steps: The sensing mechanism is movably installed on the main cable, and a pair of excitation coils and a detection coil are parallelly and spacedly arranged on the outer surface of the main cable 1; The pair of excitation coils are used to respectively pass through currents with the same frequency and opposite directions; The sensing mechanism moves along the axial direction of the main cable, and when the leakage magnetic field signal formed by the breakage of the main cable changes, the detection coil generates an induced voltage, thereby completing the detection of the breakage.

[0016] In combination with the second aspect, in an implementation, during the movement of the sensing mechanism along the axial direction of the main cable, the following steps are included: When the main cable has a breakage and the axial line of the breakage coincides with the axial line of the detection coil, the magnetic field amount in the axial direction of the detection coil in two directions cancels out each other, and the position corresponding to this state is zero position; when the sensing mechanism moves along the axial direction of the main cable before and after the zero position, the detection coil generates induced voltages with opposite directions in sequence; When the absolute value of the peak value of the induced voltages with opposite directions exceeds a set error threshold, it is determined that there is a breakage in the main cable.

[0017] In combination with the second aspect, in an implementation, the broken wire detection system further comprises a driving mechanism, the broken wire detection system further comprises a remote communication module, a signal processing module and a computer; the signal processing module is relatively fixed to the sensing mechanism and moves synchronously with the sensing mechanism; and during the movement of the sensing mechanism along the axial direction of the main cable, the following steps are included: The computer sends a motion control command to the driving mechanism through the remote communication module, thereby controlling the sensing mechanism to move along the axial direction of the main cable; The computer sends a data acquisition command to the signal processing module through the remote communication module to acquire data; The computer receives the induced voltage signal fed back by the signal processing module through the remote communication module and stores and displays the induced voltage signal, and judges whether there is a break in the main cable based on the positive and negative induced voltage signals.

[0018] The technical scheme provided by the embodiments of the present application has at least the following beneficial effects: 1. The broken wire detection system of the present application detects the break in the main cable caused by the broken wire to achieve the purpose of detecting the main cable. The sensing mechanism includes an excitation coil, a detection coil and a U-shaped armature. A pair of excitation coils are connected to pulse currents with the same frequency and opposite directions to magnetize the main cable. The U-shaped armature is used to concentrate the magnetic field and connect the magnetic fields generated by the two excitation coils. The detection coil moves along the axial direction of the main cable and senses the change of the leakage magnetic field on the surface of the main cable. When the magnetic flux changes, an induced voltage is generated. The induced voltage is used to determine the presence of a break and locate the position of the break. Compared with the traditional open cable visual method, the broken wire detection system of the present application provides a safe and non-destructive main cable detection method with high detection efficiency and accurate defect location detection. The sensing mechanism has high integration and small space occupation, and low maintenance cost. More importantly, the broken wire detection system of the present application uses pulse magnetization instead of permanent magnet magnetization. The pulse magnetization can generate a transient strong magnetic field that penetrates deep into the steel wire, achieving uniform magnetization from the surface to the inside and effectively detecting deep defects. At the same time, the parameters of pulse magnetization can be adjusted to adapt to steel wires of different materials, flexibly control the magnetization direction and strength, and supply energy on demand, which reduces resource dependence, is more suitable for scenes such as bridge main cables that require deep and accurate detection.

[0019] 2. The broken wire detection system of the present application sets a set error threshold during detection. When the output voltage of the detection coil exceeds the set error threshold, it is determined that there is a break in the main cable. This determination method is more rigorous and reliable, and has high accuracy.

[0020] 3. The broken wire detection system of the present application is only related to two variables, i.e. the broken area percentage of the steel wire inside the main cable and the broken wire width. The actual size of the induced voltage can be used to estimate the broken area percentage of the steel wire inside the main cable and the broken wire width. The broken wire detection system of the present application not only can determine whether there is a break, but also can find the position of the break, and further estimate the damage degree of the break, greatly improving the maintenance efficiency.

[0021] 4. The broken wire detection system of the present application can remotely operate the computer, drive the sensing mechanism through the driving mechanism, and also receive the induced voltage signal of the sensing mechanism in real time through the remote communication module and the signal processing module, so as to efficiently, conveniently and timely obtain the induced voltage signal, and correspondingly detect whether there is a break and find the position of the break.

[0022] 5、The detection method of the application, the operator remotely controls the detection system through the computer to perform the detection task, including that the computer sends a motion control command to the driving mechanism through the remote communication module to control the sensing mechanism to move along the main cable axial direction, the computer sends a data acquisition command to the signal processing module through the remote communication module to perform data acquisition, the computer receives the induced voltage signal fed back by the signal processing module through the remote communication module and stores and displays, and judges whether there is a break in the main cable based on the positive and negative induced voltage signals, when the magnetic flux in the detection coil changes, the induced voltage is generated, the induced voltage is transmitted to the computer after being processed by the signal processing module, and the internal wire break detection of the main cable is finally realized, which is efficient and convenient. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0024] Figure 1 The structure schematic diagram of the main cable of the traditional suspension bridge; Figure 2 The sensing module of the wire break detection system provided by the embodiment of the application; Figure 3 The block diagram of the wire break detection system provided by the embodiment of the application; In the figure: 1, main cable; 11, main cable strand; 12, putty layer; 13, wound steel wire; 14, paint layer; 111, parallel steel wire; 2, sensing mechanism; 3, driving mechanism; 4, remote communication module; 5, signal processing module; 6, computer; 21, U-shaped armature; 22, excitation coil; 23, detection coil; 1110, break. DETAILED DESCRIPTION

[0025] In order to make the person in the art better understand the application scheme, the technical solutions in the embodiments of the application will be described clearly and completely in the following with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only some of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0026] As Figure 1As shown, the main cable 1 of the suspension bridge mainly comprises, from the inside to the outside, a main cable strand 11, a putty layer 12, a winding steel wire 13, and a paint layer 14, wherein the main cable strand 11 is bundled by parallel steel wires 111 and mainly used for bearing force, and the putty layer 12, the winding steel wire 13, and the paint layer 14 constitute a main cable protection system. The main cable strand 11 inside the main cable 1 is mainly composed of multiple layers of parallel steel wires 111, and the winding steel wire 13 inside is perpendicularly wound on the surface of the parallel steel wire 111 relative to the parallel steel wire 111. Further, some main cables 1 have the winding steel wire 13, and some main cables 1 do not have the winding steel wire 13.

[0027] Generally, the parallel steel wire 111 is made of high-carbon steel material, and the winding steel wire 13 is made of medium-carbon steel, both of which are ferromagnetic materials, so that the magnetic flux leakage detection can be applied to the main cable detection. However, compared with the general wire rope and cable detection, the maximum diameter of the wire rope and cable does not exceed 300 mm, while the diameter of the main cable 1 is larger, generally greater than 300 mm in minimum diameter, and even up to 1500 mm in maximum diameter, so that it is more difficult to magnetize the main cable 1.

[0028] The application provides a main cable pulse magnetization broken wire detection system and a detection method, and provides a safe and non-destructive main cable detection method, which is high in detection efficiency and accurate in defect position detection.

[0029] As shown in the drawings, Figure 2 An embodiment of a main cable pulse magnetization broken wire detection system is disclosed, which comprises a sensing mechanism 2, and the sensing mechanism 2 comprises a U-shaped armature 21, a pair of excitation coils 22, and a detection coil 23.

[0030] The U-shaped armature 21 is used for gathering a magnetic field. The pair of excitation coils 22 are wound on the two free ends of the U-shaped armature 21 respectively, and the pair of excitation coils 22 are used for respectively inputting currents with the same frequency and opposite directions for magnetizing the main cable 1. Preferably, the pair of excitation coils 22 respectively input square waves with the same frequency and opposite current directions.

[0031] The detection coil 23 is located in the middle of the pair of excitation coils 22, specifically, the central axis of the U-shaped armature 21 coincides with the central axis of the detection coil 23. The U-shaped armature 21, the excitation coil 22, and the main cable 1 form a magnetic loop. The detection coil 23 is flush with the lower end surface of the pair of excitation coils 22, and the detection coil 23 is used for receiving a magnetic flux leakage field signal formed by the broken joint 1110 due to the broken wire of the main cable 1.

[0032] A pair of excitation coils 22 and detection coils 23 are arranged in parallel and spaced apart on the outer surface of the main cable 1 and move axially along the main cable 1. When the internal magnetic flux of the detection coil 23 changes due to the leakage magnetic field signal, an induced voltage is generated in the detection coil 23. The generation of the induced voltage indicates that the main cable 1 has a breakage 1110. Specifically, the breakage 1110 may be parallel steel wires or twisted wires. Subsequently, the breakage 1110 can be directly disassembled and repaired.

[0033] Specifically, the sensing mechanism 2 includes excitation coils 22, detection coils 23, and a U-shaped armature 21. The excitation coils 22 are internally connected to pulse current for magnetizing the main cable 1. The U-shaped armature 21 is used to concentrate the magnetic field and connect the magnetic fields generated by the two excitation coils 22. The detection coils 23 sense the change in the leakage magnetic field on the surface of the main cable 1 during axial movement along the main cable 1. In the case of a change in the magnetic flux, an induced voltage is generated. The generation of the induced voltage indicates that the main cable 1 has a breakage 1110.

[0034] Specifically, the broken wire detection system of the present application basically does not miss broken wires during actual detection. The main reason is that, compared with traditional permanent magnet magnetization, pulse magnetization can generate a transient strong magnetic field that penetrates deep into the steel wire, achieving uniform magnetization from the surface to the inside and effectively detecting deep defects.

[0035] The broken wire detection system of the present application detects the main cable by detecting the breakage 1110 caused by broken wires in the main cable 1. The sensing mechanism 2 includes excitation coils 22, detection coils 23, and a U-shaped armature 21. A pair of excitation coils 22 are internally connected to pulse current with the same frequency and opposite directions for magnetizing the main cable 1. The U-shaped armature 21 is used to concentrate the magnetic field and connect the magnetic fields generated by the two excitation coils 22. The detection coils 23 sense the change in the leakage magnetic field on the surface of the main cable 1 during axial movement along the main cable 1. In the case of a change in the magnetic flux, an induced voltage is generated. The induced voltage is used to determine the presence of a breakage 1110 and locate the position of the breakage 1110. Compared with the traditional open cable visual method, the broken wire detection system of the present application provides a safe and non-destructive main cable detection method with high detection efficiency and accurate defect location detection. The sensing mechanism 2 has high integration and small space occupation, and low maintenance cost. More importantly, the broken wire detection system of the present application uses pulse magnetization instead of permanent magnet magnetization. Pulse magnetization can generate a transient strong magnetic field that penetrates deep into the steel wire, achieving uniform magnetization from the surface to the inside and effectively detecting deep defects. The parameters of pulse magnetization can be adjusted to adapt to steel wires of different materials, flexibly control the magnetization direction and strength, and supply energy on demand, thereby reducing resource dependence, being more suitable for scenarios such as bridge main cables that require deep and accurate detection.

[0036] Further, in an embodiment, when the main cable 1 does not have a breakage 1110, no induced voltage is generated in the detection coil 23.

[0037] When the main cable has a break 1110 and the break 1110 is exactly in the symmetry center line of the detection coil 23 (the axis of the break 1110 coincides with the axis of the detection coil 23), the magnetic field amount in the two axial directions inside the detection coil 23 cancels each other, and this state corresponds to the zero position.

[0038] When the main cable has a break 1110 and the axis of the break 1110 coincides with the axis of the detection coil 23, the magnetic fields in the two directions of the detection coil 23 cancel each other in the axial direction of the detection coil 23. Specifically, the magnetic fields in the two directions of the detection coil 23 represent the positive and negative directions of the axis of the detection coil 23.

[0039] Specifically, when the axis of the break 1110 coincides with the axis of the detection coil 23, the leakage magnetic flux in the positive axial direction of the detection coil 23 (the magnetic flux in the direction of the arrow Figure 2 in the figure) Φ C is equal to the leakage magnetic flux in the negative axial direction of the detection coil 23 (the magnetic flux in the direction of the arrow Figure 2 in the figure) Φ D , and cancels each other. During movement, when the axis of the break 1110 is located on the left or right of the axis of the detection coil 23 (i.e. before or after the zero position), the magnetic field strength in one direction of the detection coil 23 is greater than that in the other direction, and a positive and negative induced voltage is generated.

[0040] As shown in the example, when the break 1110 is located on the right of the axis of the detection coil 23, the leakage magnetic flux of the break 1110 Figure 2 Φ D is mostly located outside the detection coil 23, Φ C and Φ D the effective magnetic flux inside the detection coil is Φ C main. Similarly, when the break 1110 is located on the left of the axis of the detection coil 23, the leakage magnetic flux of the break 1110 Φ C is mostly located outside the detection coil 23, Φ C and Φ D the effective magnetic flux inside the detection coil 23 is Φ D main. Therefore, when the break 1110 of the main cable 1 is exactly in the symmetry center line of the detection coil 23, Φ C and Φ D cancels each other.

[0041] ​Preferably, the two free ends of the U-shaped armature 21 are arc-shaped, and the contact area of each free end with the main cable 1 is set according to requirements. The free end can be set to be able to correspondingly close to one-half, one-third or one-fourth of the circumferential surface of the main cable 1, and the sensing mechanism 2 needs to detect twice, three times or four times, respectively, to detect the entire circumferential surface of the main cable 1.

[0042] Further, when the sensing mechanism 2 moves axially along the main cable 1 through the zero position, the detection coil 23 generates an induced voltage in opposite directions.

[0043] Specifically, when there is no gap 1110 in the main cable 1 or the gap 1110 is exactly on the symmetry line of the detection coil 23 (the axis of the gap 1110 coincides with the axis of the detection coil 23), it is at the zero position, and exactly in the process of the detection coil 23 approaching the gap 1110 (before the zero position) and moving away from the gap 1110 (after the zero position) will generate an induced voltage in opposite directions.

[0044] Specifically, according to the principle of electromagnetic induction, the induced voltage inside the detection coil 3 is e :

[0045] In the formula, N is the number of turns of the detection coil, Φ A and Φ B from the background magnetic field generated by the excitation coil 23; Φ C and Φ D from the leakage magnetic field generated by the gap 1110 inside the main cable 1. The background magnetic field generated by the excitation coil 23 and the leakage magnetic field at the gap 1110 are both derived from the square wave excitation inside the excitation coil 23. They not only have the same frequency but also have the same phase. Φ A , Φ B , Φ C and Φ D The components in the direction of the axis of the main cable x superimpose on each other, but the magnetic flux in this direction does not pass through the detection coil 23, and will not generate an induced voltage in the detection coil 23: .

[0046] Due to the symmetry of the structure of the excitation coil 23, Φ A and Φ B in the axis direction of the detection coil 3 The components in the direction cancel each other out: .

[0047] Therefore, the detection coil 23 is not sensitive to the magnetic flux of the background magnetic field generated by the excitation coil 22, but only to the magnetic flux of the leakage magnetic field at the break 1110 of the main cable 1.

[0048] Therefore, when there is no break 1110 in the main cable 1, or the break 1110 is exactly in the symmetry center line of the detection coil 23, the magnetic flux cancels each other out and is at zero position; when the sensing mechanism 2 moves along the main cable axis before and after the zero position, the detection coil 23 will generate an induced voltage in opposite directions on both sides of the break 1110. As an example in Φ , the induced voltage is as follows: .

[0049] Further, in theory, if there is no break 1110 inside the main cable 1, i.e. there is no leakage magnetic field on the surface of the main cable 1, the magnetic flux inside the detection coil 23 does not change, and the detection coil 23 always has no output voltage. However, considering the reality, the output voltage of the detection coil 23 is fluctuating within a certain range, therefore, a set error threshold is set during the detection process, and only when the output voltage of the detection coil 23 exceeds the set error threshold, it can be determined that there is a break 1110 inside the main cable 1.

[0050] When the absolute value of the peak value of the induced voltage exceeds the set error threshold, it is determined that there is a break 1110 inside the main cable 1.

[0051] The broken wire detection system of the present application sets a set error threshold during the detection process, and determines that there is a break 1110 inside the main cable 1 when the output voltage of the detection coil 23 exceeds the set error threshold. This determination method is more rigorous and reliable, and has high accuracy.

[0052] Further, in an embodiment, the output voltage of the detection coil 23 is the induced voltage generated by the leakage magnetic field of the break 1110 of the broken wire in the detection coil 23 : ; In the formula, is the known excitation magnetic field strength; Figure 2 is the percentage of the broken wire area (i.e. the percentage of the cross-sectional area of the break relative to the cross-sectional area of the whole main cable), ΔA is the width of the break ( ΔG in the left and right directions of the break), Figure 2 is the known vertical distance between the detection coil 23 and the main cable 1. The induced voltage is related to the internal ΔL and ΔA.

[0053] In the detection process, the excitation magnetic field strength and the vertical distance between the detection coil and the main cable are known values, so the induced voltage generated inside the detection is only related to the percentage of the broken area of the steel wire inside the main cable 1 and the broken wire width.

[0054] The broken wire detection system of the application is only related to two variables, i.e. the percentage of the broken area of the steel wire inside the main cable 1 and the broken wire width. The actual size of the induced voltage can be used to estimate the percentage of the broken area of the steel wire inside the main cable 1 and the broken wire width. The broken wire detection system of the application can not only determine whether there is a broken seam, but also find the position of the broken seam, and further estimate the damage degree of the broken seam, greatly improving the maintenance efficiency.

[0055] In an example, the U-shaped armature is made of industrial pure iron, the inner diameter of the excitation coil 22 is 80 mm, the number of turns is 100 turns, the inner diameter of the detection coil 23 is 80 mm, and the number of turns is 100 turns.

[0056] As shown in ΔG Figure 3 Further, in an embodiment, the broken wire detection system further comprises a driving mechanism 3, which includes a motion control circuit and a motor. The motion control circuit controls the rotation and stop of the motor, and the motor provides power for the axial movement of the sensing mechanism along the main cable 1.

[0057] Further, in an embodiment, the broken wire detection system further comprises a remote communication module 4, a signal processing module 5 and a computer 6. The signal processing module 5 is relatively fixed to the sensing mechanism 2 and moves synchronously with the sensing mechanism 2.

[0058] The signal processing module 5 filters and amplifies the induced voltage signal transmitted by the sensing mechanism 2.

[0059] The remote communication module 4 establishes communication between the computer 6 and the driving mechanism 3 and the signal processing module 5.

[0060] The broken wire detection system of the application can remotely operate the computer 6, drive the sensing mechanism 2 through the driving mechanism 3, and also receive the induced voltage signal of the sensing mechanism 2 in real time through the remote communication module 4 and the signal processing module 5. The induced voltage signal can be efficiently, conveniently and timely obtained, and the presence or absence of the broken seam 1110 can be detected and the position of the broken seam 1110 can be found.

[0061] Specifically, the detection coil 23 and the U-shaped armature 21 are fixed by an insulating material.

[0062] In a second aspect, an embodiment of a detection method of the above broken wire detection system is disclosed, which comprises the following steps: The sensing mechanism 2 is movably installed on the main cable 1, and a pair of excitation coils 22 and a detection coil 23 are parallel and spaced on the outer surface of the main cable 1; The pair of excitation coils 22 are respectively used to pass in the same frequency and opposite direction current; The sensing mechanism 2 moves along the main cable 1 in the axial direction, and when the internal magnetic flux of the detection coil 23 changes due to the leakage magnetic field signal formed by the broken gap 1110 of the main cable 1 due to broken wires, the detection coil 23 generates an induced voltage, and the broken gap detection is completed.

[0063] Regarding the detection method, in one embodiment, the sensing mechanism 2 moves along the main cable 1 in the axial direction, including: When the main cable has a broken gap 1110 and the axis of the broken gap 1110 coincides with the axis of the detection coil 23, the magnetic field amount in the axial direction of the detection coil 23 cancels each other, and this state corresponds to the zero position; When the sensing mechanism 2 moves along the main cable 1 in the axial direction before and after the zero position, the detection coil 23 generates induced voltages in opposite directions in turn; When the absolute value of the peak value of the induced voltages in opposite directions exceeds the set error threshold, it is determined that there is a broken gap 1110 inside the main cable 1.

[0064] Regarding the detection method, in one embodiment, the broken wire detection system further includes a driving mechanism 3, and the broken wire detection system further includes a remote communication module 4, a signal processing module 5 and a computer 6; The signal processing module 5 is relatively fixed to the sensing mechanism 2, and both are synchronous motion; The sensing mechanism 2 moves along the main cable 1 in the axial direction, including: The computer 6 sends a motion control command to the driving mechanism 3 through the remote communication module 4 to control the sensing mechanism 2 to move along the main cable 1 in the axial direction; The computer 6 sends a data acquisition command to the signal processing module 5 through the remote communication module 4 to acquire data; The computer 6 receives the induced voltage signal fed back by the signal processing module 5 through the remote communication module 4 and stores and displays it, and determines whether there is a broken gap inside the main cable 1 based on the induced voltage signal. When there are positive and negative induced magnetic fields, and the absolute value of the peak value exceeds the set error threshold, it is determined that there is a broken gap 1110 inside the main cable 1.

[0065] The detection method of the application, the operator remotely controls the detection system through the computer 6 to perform the detection task, including that the computer 6 sends a motion control command to the driving mechanism 3 through the remote communication module 4 to control the sensing mechanism 2 to move along the main cable 1 in the axial direction, the computer 6 sends a data acquisition command to the signal processing module 5 through the remote communication module 4 to acquire data, the computer 6 receives the induced voltage signal fed back by the signal processing module 5 through the remote communication module 4 and stores and displays it, and judges whether there is a break in the main cable 1 based on whether the positive and negative induced voltage signals are generated, when the magnetic flux in the detection coil changes, thereby generating an induced voltage, the induced voltage is transmitted to the computer 6 after being processed by the signal processing module 5, and finally the internal break of the main cable 1 is detected, which is efficient and convenient.

[0066] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, and it can be the communication between two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0067] It should be noted that in the present application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0068] The foregoing detailed description of the application has been presented for purposes of illustration and description. Various modifications and changes can be made to these embodiments without departing from the spirit and scope of the application. It is intended that the scope of the application should not be limited by the particular representative embodiments described above.

Claims

1. A main cable pulse magnetization broken wire detection system, characterized in that: The broken wire detection system comprises a sensing mechanism (2), wherein the sensing mechanism (2) comprises: U-shaped armature (21); A pair of excitation coils (22) are respectively wound around two free ends of the U-shaped armature (21), and the pair of excitation coils (22) are used to respectively pass currents of the same frequency and opposite directions to magnetize the main cable (1); A detection coil (23) is located in the middle of the pair of excitation coils (22) and is flush with the lower end surface of the excitation coil (22). The detection coil (23) is used to receive a leakage magnetic field signal generated by a break (1110) caused by a broken wire in the main cable (1); The pair of excitation coils (22) and detection coils (23) are arranged in parallel and spaced apart on the outer surface of the main cable (1) and move along the axial direction of the main cable (1). When the magnetic flux inside the detection coil (23) changes due to the leakage magnetic field signal, the detection coil (23) generates an induced voltage.

2. A main cable pulse magnetization broken wire detection system according to claim 1, characterized in that: When the main cable has a break (1110) and the axis of the break (1110) coincides with the axis of the detection coil (23), the magnetic fields in two axial directions inside the detection coil (23) cancel each other out, and the position corresponding to this state is zero.

3. A main cable pulse magnetization broken wire detection system according to claim 2, characterized in that: During the movement of the sensing mechanism (2), when the sensing mechanism (2) moves axially along the main cable (1) and passes before and after the zero position, the detection coil (23) successively generates induced voltages in opposite directions.

4. A main cable pulse magnetization broken wire detection system according to claim 3, characterized in that: When the absolute value of the peak value of the induced voltage in the opposite direction exceeds a set error threshold, it is determined that a fracture (1110) exists inside the main cable (1).

5. The main cable pulse magnetization broken wire detection system according to claim 1, characterized in that: The output voltage of the detection coil (23) is the induced voltage generated in the detection coil (23) by the leakage magnetic field at the fracture (1110) of the broken wire. : ； Where, is the known excitation magnetic field strength; ΔA is the percentage of the broken area of ​​the steel wire, ΔG is the fracture width, ΔL is the known vertical distance between the detection coil (23) and the main cable (1); the induced voltage Related to the interior of the main cable (1) ΔA and ΔG .

6. The main cable pulse magnetization broken wire detection system according to claim 1, characterized in that: The broken wire detection system further comprises a driving mechanism (3), wherein the driving mechanism (3) comprises a motion control circuit and a motor, wherein the motion control circuit controls the rotation and stop of the motor, and the motor provides power for the sensing mechanism to move axially along the main cable (1).

7. A main cable pulse magnetization broken wire detection system according to claim 6, characterized in that: The broken wire detection system further comprises a remote communication module (4), a signal processing module (5) and a computer (6); the signal processing module (5) is relatively fixed to the sensing mechanism (2), and the two move synchronously; The signal processing module (5) performs filtering and amplification processing on the induced voltage signal transmitted from the sensing mechanism (2), and the remote communication module (4) establishes communication between the computer (6), the driving mechanism (3), and the signal processing module (5).

8. A detection method based on the broken wire detection system according to claim 1, characterized in that: Contains steps: The sensing mechanism (2) is movably mounted on the main cable (1), and a pair of excitation coils (22) and detection coils (23) are parallel and spaced apart from each other on the outer surface of the main cable 1; A pair of excitation coils (22) are used to respectively pass currents of the same frequency and opposite directions; The sensing mechanism (2) moves axially along the main cable (1). When the leakage magnetic field signal formed by the internal magnetic flux of the detection coil (23) due to the broken wire (1110) of the main cable (1) changes, the detection coil (23) generates an induced voltage to complete the break detection.

9. The detection method according to claim 8, wherein The sensing mechanism (2) moves along the axial direction of the main cable (1), including: When the main cable has a break (1110) and the axis of the break (1110) coincides with the axis of the detection coil (23), the magnetic fields in the two axial directions inside the detection coil (23) cancel each other out, and this state corresponds to a zero position; when the sensing mechanism (2) moves axially along the main cable (1) before and after the zero position, the detection coil (23) generates induced voltages in opposite directions successively; When the absolute value of the peak value of the induced voltage in the opposite direction exceeds a set error threshold, it is determined that a fracture (1110) exists inside the main cable (1).

10. The detection method according to claim 8, wherein: The broken wire detection system further comprises a driving mechanism (3), a remote communication module (4), a signal processing module (5) and a computer (6); the signal processing module (5) is relatively fixed to the sensing mechanism (2), and the two move synchronously; during the axial movement of the sensing mechanism (2) along the main cable (1), the system comprises: The computer (6) sends a motion control command to the driving mechanism (3) via the remote communication module (4), thereby controlling the sensing mechanism (2) to move axially along the main cable (1); The computer (6) sends a data acquisition command to the signal processing module (5) via the remote communication module (4) to perform data acquisition; The computer (6) receives the induced voltage signal fed back by the signal processing module (5) through the remote communication module (4), stores and displays the signal, and determines whether there is a fracture inside the main cable (1) based on the positive and negative induced voltage signals.

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