Nondestructive testing device and method for lightning protection grounding grid

Abstract

The invention belongs to the technical field of lightning protection detection, and particularly relates to a nondestructive testing device and method for a lightning protection grounding grid. Various existing detection methods have limitations, and the electrical performance is difficult to evaluate. Comprising a moving trolley; the mechanical arm is fixedly connected to the moving trolley; the electromagnetic induction detection unit is fixedly connected to the moving end of the mechanical arm, the electromagnetic induction detection unit is composed of a high-frequency transmitting coil and a receiving coil, the high-frequency transmitting coil is used for enabling a grounding grid to generate induced current, and the receiving coil is used for capturing a magnetic field signal generated by the induced current in the grounding grid; and the data acquisition and processing unit is arranged in the moving trolley. According to the invention, the grounding grid is nondestructively detected by adopting an electromagnetic induction principle, faults such as corrosion and connection conditions are effectively judged by combining high-precision data acquisition and an advanced signal analysis algorithm, comprehensive performance of the grounding grid can be comprehensively evaluated, and reliable operation of a lightning protection grounding system is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lightning protection detection, and in particular to a lightning protection grounding net nondestructive testing device and method. BACKGROUND

[0002] The lightning protection grounding net is the core component in the lightning protection system, and its effectiveness is directly related to whether the building and power facilities can successfully resist the risk brought by lightning. The grounding net is in contact with the soil for a long time, and the grounding net may suffer from soil corrosion, loose or broken connection points, etc. These problems will cause the increase of grounding resistance and reduce the working efficiency of the grounding net. Therefore, in order to ensure the effectiveness and reliability of the lightning protection grounding net, it is necessary to detect it regularly, which helps to find and solve possible problems in time and ensure that the lightning protection grounding net is always in good working condition. The existing detection methods include traditional grounding resistance measurement, electrical integrity testing technology and ground penetrating radar detection technology.

[0003] The traditional grounding resistance measurement method includes three-point method and clamp-on method. The three-point method requires a large site and complex electrode arrangement, and the clamp-on method measures the grounding loop current by using electromagnetic induction to indirectly calculate the resistance. It is suitable for downlead resistance, but its detection ability for the overall corrosion and connection condition of the grounding net is limited.

[0004] The electrical integrity testing technology is mainly used for detecting the electrical continuity of the grounding net connection part, and the connection point state is judged by comparing the resistance or measuring the potential gradient. However, these methods only provide simple connection information, which is not enough to comprehensively evaluate the overall performance of the grounding net.

[0005] The ground penetrating radar detection technology mainly detects the position and approximate shape of the grounding net according to the reflection characteristics of electromagnetic waves in underground medium, but its detection ability for the electrical performance parameters (such as grounding resistance, corrosion degree, etc.) of the grounding net is weak.

[0006] In summary, although the currently available grounding net detection methods have their own characteristics, the information provided by each method is relatively limited, and when used alone, it is difficult to comprehensively and deeply evaluate the overall performance and health condition of the grounding net. SUMMARY

[0007] In order to overcome the shortcomings mentioned in the background art, the present application provides a lightning protection grounding net nondestructive testing device and method.

[0008] Technical solution: A lightning protection grounding grid nondestructive testing device, comprising: a mobile trolley; a mechanical arm fixedly connected to the mobile trolley; an electromagnetic induction detection unit fixedly connected to the moving end of the mechanical arm, the electromagnetic induction detection unit is composed of a high-frequency transmitting coil and a receiving coil, the high-frequency transmitting coil is used for generating induced current in the grounding grid, and the receiving coil is used for capturing the magnetic field signal generated by the induced current in the grounding grid; a data acquisition and processing unit arranged in the mobile trolley and electrically connected with the electromagnetic induction detection unit, the data acquisition and processing unit is used for calculating and analyzing the magnetic field signal captured by the receiving coil.

[0009] In addition, it is particularly preferred that the detection assembly is arranged in the mobile trolley and is used for detecting the distance change between the electromagnetic induction detection unit and the grounding grid, the mobile trolley is spliced by a reference vehicle and a detection vehicle, and the mechanical arm is located on the detection vehicle; the detection assembly comprises: two fixed frames fixedly connected to the reference vehicle and the detection vehicle respectively, the fixed frame is rotatably connected with a rotating frame, the rotating frame is fixedly connected with a reference cylinder, the bottoms of the two reference cylinders are fixedly connected and communicated with a connecting hose, the rotating frame is fixedly connected with a liquid level sensor for detecting the liquid level in the adjacent reference cylinder, and the fixed frame is provided with a feedback assembly for detecting the inclination angle of the detection vehicle.

[0010] In addition, it is particularly preferred that the feedback assembly comprises: a spur gear fixedly connected to the rotating frame; a rack frame slidingly connected to the fixed frame, the spur gear is engaged with the rack frame; a trigger assembly arranged on the fixed frame and used for detecting the displacement change of the rack frame; and a locking assembly arranged on the fixed frame and used for locking the rotating frame.

[0011] In addition, it is particularly preferred that the trigger assembly comprises: a pressure sensor fixedly connected to the fixed frame; and a first elastic element arranged between the pressure sensor and the rack frame.

[0012] In addition, it is particularly preferred that the locking assembly comprises: a plug shaft slidingly connected to the fixed frame, the plug shaft is used for limiting the adjacent rack frame; a second elastic element arranged between the plug shaft and the fixed frame; and a driving assembly arranged on the fixed frame and used for driving the plug shaft to move.

[0013] In addition, it is particularly preferred that the driving assembly comprises: a magnetic block fixedly connected to the plug shaft; and an electromagnet fixedly connected to the fixed frame and used for attracting the magnetic block.

[0014] Furthermore, it is particularly preferred that the vibration assembly further comprises two vibration assemblies respectively arranged on the two rotating frames and used for vibrating the reference cylinder, and the vibration assembly comprises a plurality of connecting frames fixedly connected to the outside of the reference cylinder, a plurality of knocking shafts in abutment with adjacent connecting frames and slidably connected to the connecting frames, and a third elastic element arranged between the knocking shaft and the adjacent connecting frame.

[0015] Furthermore, it is particularly preferred that the power assembly comprises a first motor fixedly connected to the rotating frame, a spline shaft fixedly connected to the output shaft of the first motor, a pressing block spline-connected to the spline shaft and used for pushing the adjacent knocking shaft, and a transposition assembly arranged on the rotating frame and used for changing the position of the pressing block.

[0016] Furthermore, it is particularly preferred that the transposition assembly comprises a second motor fixedly connected to the rotating frame, a lead screw fixedly connected to the output shaft of the second motor, and a push block threadedly connected to the lead screw and limitingly and slidably connected to the pressing block.

[0017] A lightning protection grounding grid nondestructive detection method, applying the lightning protection grounding grid nondestructive detection device, comprises the following steps: Step 1: move the device to the detection position of the grounding grid to be detected, and control the mechanical arm to drive the electromagnetic induction detection unit to the upper side of the grounding grid, so that the axes of the transmitting coil and the receiving coil are strictly perpendicular to the main trend of the grounding grid; Step 2: turn on the high-frequency signal generator and the receiving coil, the transmitting coil is used for generating an alternating magnetic field, the magnetic field can penetrate the ground and act on the grounding grid, so that the grounding grid generates an induced current and a secondary magnetic field, and the receiving coil is responsible for capturing the secondary magnetic field signal; Step 3: the data acquisition and processing unit analyzes and calculates the secondary magnetic field signal captured by the receiving coil, and accurately calculates the corresponding parameter change amount, such as the increase amplitude of the resistance and the change value of the inductance, so as to provide a quantitative basis for the performance evaluation of the grounding grid; Step 4: for the suspected problem area found in the preliminary detection, multiple repeated detections are needed, and in each repeated detection, the magnetic induction detection unit is translated in the horizontal direction or adjusted in height, and the current frequency of the transmitting coil is changed, so as to obtain detection signals at different angles and depths.

[0018] Compared with the prior art, the present application has the following advantages: 1. The grounding grid is nondestructively detected by adopting the electromagnetic induction principle, and combined with high-precision data acquisition and advanced signal analysis algorithm, the corrosion, connection condition and other faults are effectively judged, the comprehensive performance of the grounding grid can be comprehensively evaluated, and the reliable operation of the lightning protection grounding system is ensured.

[0019] 2、By detecting the height change of the detection vehicle, and controlling the mechanical arm to drive the electromagnetic induction detection unit to adjust the height, the distance between the electromagnetic induction detection unit and the grounding net is restored to the initial state before changing the parameters, thereby improving the precision of the electromagnetic induction detection unit in detecting the grounding net.

[0020] 3、By detecting the inclination angle of the detection vehicle, and further controlling the mechanical arm to deflect the electromagnetic induction detection unit, the receiving direction of the electromagnetic induction detection unit is changed, so that the electromagnetic induction detection unit is always perpendicular to the ground, thereby improving the detection precision of the electromagnetic induction detection unit.

[0021] 4、By knocking the outer wall of the reference cylinder from top to bottom in sequence, the vibration drives the water droplets attached to the inner wall of the reference cylinder downward, and the water droplets slide downward under the vibration and gather in the water in the reference cylinder, thereby avoiding the attachment of water droplets on the inner wall of the reference cylinder, which causes the liquid level sensor to fail to detect the actual change of the liquid level, and further reduces the detection precision of the grounding net. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a perspective structural schematic view of the present application; Figure 2 It is a perspective structural sectional view of the mobile trolley of the present application; Figure 3 It is a perspective structural schematic view of the mechanical arm of the present application; Figure 4 It is a perspective structural schematic view of the rotating frame and the reference cylinder of the present application; Figure 5 It is a perspective structural schematic view of the straight gear and the rack frame of the present application; Figure 6 It is a perspective structural schematic view of the inserted shaft and the second elastic element of the present application; Figure 7 It is a perspective structural schematic view of the connecting frame and the knocking shaft of the present application; Figure 8 It is a perspective structural schematic view of the lead screw and the push block of the present application.

[0023] The figure label name: 1, mobile trolley, 2, mechanical arm, 3, electromagnetic induction detection unit, 4, data acquisition and processing unit, 11, reference car, 12, detection car, 201, fixed frame, 202, rotating frame, 203, reference cylinder, 204, connecting hose, 205, liquid level sensor, 301, straight gear, 302, rack frame, 303, pressure sensor, 304, first elastic element, 401, plug shaft, 402, second elastic element, 403, magnetic block, 404, electromagnet, 501, connecting frame, 502, knocking shaft, 503, third elastic element, 504, first motor, 505, spline shaft, 506, extrusion block, 601, second motor, 602, lead screw, 603, push block. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0025] Although the current grounding grid detection methods have their own characteristics, but each method can reveal limited information, and it is difficult to evaluate the overall performance and health status of the grounding grid in depth by relying on any one of them alone. This means that the existing detection technology may not be able to provide enough information to fully reflect the performance of the grounding grid and its potential problems when applied alone.

[0026] A lightning protection grounding grid nondestructive detection device, as shown in Figures 1-3 The device includes a mobile trolley 1, a mechanical arm 2 fixedly connected to the mobile trolley 1, an electromagnetic induction detection unit 3 fixedly connected to the moving end of the mechanical arm 2, the electromagnetic induction detection unit 3 composed of a high-frequency transmitting coil and a receiving coil, the high-frequency transmitting coil for generating an induced current in the grounding grid, and the receiving coil for capturing the magnetic field signal generated by the induced current in the grounding grid, a data acquisition and processing unit 4 arranged in the mobile trolley 1 and electrically connected with the electromagnetic induction detection unit 3, the data acquisition and processing unit 4 for calculating and analyzing the magnetic field signal captured by the receiving coil.

[0027] In the above scheme, the mobile trolley 1 is composed of a support and several rollers, the support is made of aluminum alloy material which is light, has high strength and good corrosion resistance, ensuring the structure is stable while facilitating flexible movement in various complex detection sites, the mechanical arm 2 is a six-axis mechanical arm, which not only has multiple spatial coordinates for positioning, but also can control the attitude (i.e. angle and direction) of the moving end, which makes it can adapt to more work task requirements, the high-frequency transmitting coil in the electromagnetic induction detection unit 3 generates a frequency of 10kHz-100kHz high-frequency alternating current, the receiving coil is connected with a signal amplifier and a filter, the signal amplifier is used to amplify the weak induction signal and improve the amplitude of the signal, and the filter is used to remove noise and various interference components in the signal.

[0028] The core components of the data acquisition and processing unit 4 are a high-speed data acquisition card and a microprocessor, the high-speed data acquisition card has a collection frequency of not less than 1MHz, which can collect the amplified and filtered induction signal in real time and continuously at a very high rate, ensuring that all detailed information in the signal is captured completely, including its small amplitude changes, rapid frequency fluctuations and subtle phase shifts, etc. The high-speed data acquisition card rapidly transmits the collected digital signal to the microprocessor, and the microprocessor accurately converts the time-domain signal to the frequency-domain signal for in-depth analysis of the amplitude distribution and phase change of the signal at different frequency bands.

[0029] The mobile trolley 1 can also be provided with a touch screen display and a database, the parameters can be changed through the touch screen display, and various detailed information of the detection results can be presented in real time, so as to intuitively show the health degree of the grounding grid in the form of graphs, charts or text descriptions, etc. At the same time, the database can store detection data, realize long-term preservation, centralized management and deep mining of data, and provide strong data support for subsequent grounding grid maintenance plan making, performance trend analysis and fault prediction, etc.

[0030] When the grounding grid needs to be detected, the staff pushes the device to the detection position of the grounding grid according to the laying drawing of the grounding grid, and opens the mechanical arm 2, so that the moving end of the mechanical arm 2 drives the electromagnetic induction detection unit 3 to stably hover at a specific height above the detection position of the grounding grid, ensures that the axes of the high-frequency transmitting coil and the receiving coil are strictly perpendicular to the main bus direction of the grounding grid, and forms the best electromagnetic coupling state, and then the parameters are set through the touch screen display, when the parameter adjustment is completed, the electromagnetic induction detection unit 3 is started, the high-frequency transmitting coil generates a high-strength alternating magnetic field in the surrounding space, the alternating magnetic field radiates and propagates in all directions with the high-frequency transmitting coil as the center, so that the alternating magnetic field penetrates the ground and acts on the grounding grid, so that the grounding grid generates induced current and secondary magnetic field, at this time the receiving coil captures the signal of the secondary magnetic field, the signal amplifier connected with the receiving coil amplifies the weak induced signal, improves the amplitude of the signal, so as to meet the requirements of subsequent data acquisition and processing, the filter eliminates noise and various interference in the signal, such as electromagnetic interference and stray current interference in the environment, thereby greatly improving the signal-to-noise ratio of the signal, ensuring that the obtained signal is pure, stable and accurate, and providing a reliable basis for subsequent accurate analysis, and then the data acquisition and processing unit 4 analyzes the collected signal, judges the possible corrosion, poor connection or other abnormal conditions in the grounding grid, so as to realize the detection of the grounding grid, the present application detects the grounding grid by adopting the electromagnetic induction principle, and combines high-precision data acquisition and advanced signal analysis algorithm, effectively judges corrosion, connection condition and other faults, can comprehensively evaluate the comprehensive performance of the grounding grid, and ensures the reliable operation of the lightning protection grounding system.

[0031] When the staff finds that the amplitude of the induced signal in the detection area is generally lower than the normal expected level, it is necessary to repeatedly detect the area several times to determine the rigor of the grounding grid detection data and the specific situation of the grounding grid, at this time the position of the device needs to be adjusted appropriately, and the device is translated in the horizontal direction by a certain length, and the signal strength and height of the electromagnetic induction detection unit 3 are adjusted, and a plurality of groups of data are compared, but in the process of translation of the device, the height of the electromagnetic induction detection unit 3 and the grounding grid is easily changed due to the change of the ground, and then the set parameters are different from the actual parameters, which causes the inaccuracy of the detection data.

[0032] In further embodiments, as Figures 1-4As shown, the detection assembly is arranged in the mobile trolley 1, and is used for detecting the change of the distance between the electromagnetic induction detection unit 3 and the grounding net. The mobile trolley 1 is spliced by the reference trolley 11 and the detection trolley 12, and the mechanical arm 2 is located on the detection trolley 12. The detection assembly comprises two fixed frames 201 which are fixedly connected to the reference trolley 11 and the detection trolley 12 respectively. The fixed frame 201 is rotationally connected with a rotating frame 202. The rotating frame 202 is fixedly connected with a reference cylinder 203. The bottoms of the two reference cylinders 203 are fixedly connected and communicated with a connecting hose 204. The rotating frame 202 is fixedly connected with a liquid level sensor 205 which is used for detecting the liquid level in the adjacent reference cylinder 203. The fixed frame 201 is provided with a feedback assembly which is used for detecting the inclination angle of the detection trolley 12.

[0033] In the above scheme, the materials of the fixed frame 201 and the rotating frame 202 are aluminum alloy. The two reference cylinders 203 and the connecting hose 204 are filled with water. The three components form a communicating vessel. In the initial state, the water levels in the two reference cylinders 203 are located at the middle positions of the reference cylinders 203. The connecting hose 204 has a sufficient length to adapt to the position change between the reference trolley 11 and the detection trolley 12. The liquid level sensor 205 is an ultrasonic sensor, and is located directly above the adjacent reference cylinder 203. The liquid level sensor 205 detects the change of the liquid level in the reference cylinder 203 to determine the change of the height of the detection trolley 12, and then controls the mechanical arm 2 to change the position of the electromagnetic induction detection unit 3.

[0034] Specifically, as shown in Figure 4 and Figure 5 The feedback assembly comprises a spur gear 301 which is fixedly connected to the rotating frame 202, a rack frame 302 which is slidingly connected to the fixed frame 201, and the spur gear 301 is engaged with the rack frame 302. The feedback assembly further comprises a trigger assembly which is arranged on the fixed frame 201 and is used for detecting the displacement change of the rack frame 302, and a locking assembly which is arranged on the fixed frame 201 and is used for locking the rotating frame 202.

[0035] In the above scheme, the materials of the spur gear 301 and the rack frame 302 are aluminum alloy, which is light and has good corrosion resistance. When the detection trolley 12 or the reference trolley 11 is in an inclined state, the reference cylinder 203 and the adjacent fixed frame 201 will rotate relatively. At this time, the fixed frame 201 will drive the rack frame 302 to slide along the fixed frame 201 through the adjacent spur gear 301.

[0036] Specifically, as shown in Figure 4 and Figure 5 The trigger assembly comprises a pressure sensor 303 which is fixedly connected to the fixed frame 201, and a first elastic element 304 which is arranged between the pressure sensor 303 and the rack frame 302.

[0037] In the above scheme, the pressure sensor 303 is electrically connected with the data acquisition and processing unit 4, the first elastic element 304 is a spring and the initial state is a compressed state, the elastic force of the first elastic element 304 is smaller than the self-gravity of the reference cylinder 203, the inclination angle of the detection vehicle 12 can be detected according to the compression degree of the first elastic element 304, that is, the force acting on the pressure sensor 303, and then the mechanical arm 2 is controlled to deflect the electromagnetic induction detection unit 3, the receiving direction of the electromagnetic induction detection unit 3 is adjusted to the initial state, and the precision of the electromagnetic induction detection unit 3 in detecting the grounding grid is improved.

[0038] Specifically, as shown in Figure 5 and Figure 6 , the locking assembly comprises: an insertion shaft 401 slidingly connected to the fixed frame 201, the insertion shaft 401 being used for limiting the adjacent rack frame 302; a second elastic element 402 arranged between the insertion shaft 401 and the fixed frame 201; and a driving assembly arranged on the fixed frame 201 and used for driving the insertion shaft 401 to move.

[0039] In the above scheme, the second elastic element 402 is a spring, which is used for driving the adjacent insertion shaft 401 to reset, limiting the rack frame 302 through the insertion shaft 401, and ensuring that the reference cylinder 203 remains in a vertical state during detection.

[0040] Specifically, as shown in Figure 5 and Figure 6 , the driving assembly comprises: a magnetic block 403 fixedly connected to the insertion shaft 401; and an electromagnet 404 fixedly connected to the fixed frame 201 and used for attracting the magnetic block 403.

[0041] In the above scheme, the magnetism generated by the electromagnet 404 after being energized is the same as the magnetism possessed by the magnetic block 403 itself, which is used for driving the magnetic block 403 to move the adjacent insertion shaft 401 downward, and by releasing the locking of the insertion shaft 401 on the reference cylinder 203 when the detection vehicle 12 changes position, the reference cylinder 203 is always in a vertical state during the position change.

[0042] When the detection position needs to be switched, the worker splits the trolley 1 into the reference trolley 11 and the detection trolley 12, then maintains the reference trolley 11 in place, drives the detection trolley 12 to the required detection position, and drives the mechanical arm 2 on the detection trolley 12 to the required position synchronously. When the terrain changes (here, the change is taken as an example of rising), the distance from the detection trolley 12 to the grounding net is greater than the distance from the reference trolley 11 to the grounding net, but due to the principle of the communicating vessel, the water level in the reference cylinder 203 on the detection trolley 12 drops with itself as the reference, and the water level in the reference cylinder 203 on the reference trolley 11 rises with itself as the reference, so that the water levels in the two reference cylinders 203 are in the same state with the grounding net as the reference height. At this time, the liquid level sensor 205 detects the change of the water level in the reference cylinder 203, and then the data acquisition and processing unit 4 judges the height change of the detection trolley 12, and controls the mechanical arm 2 to drive the electromagnetic induction detection unit 3 to adjust the height, so that the distance from the electromagnetic induction detection unit 3 to the grounding net returns to the initial state, and then the parameter is changed, which improves the precision of the electromagnetic induction detection unit 3 in detecting the grounding net.

[0043] When the position needs to be changed again, the reference trolley 11 is pushed to splice with the detection trolley 12, then the detection trolley 12 is pushed to the next detection position, and the above steps are repeated, and so on until the detection is completed.

[0044] When the detection trolley 12 changes the detection position, the electromagnet 404 is turned on, so that the electromagnet 404 has a magnetic force, and drives the magnetic block 403 to move downward, the magnetic block 403 drives the adjacent plug shaft 401 to move downward, the second elastic element 402 is compressed, so that the plug shaft 401 is separated from the adjacent rack frame 302, the adjacent rack frame 302 is released, so that the reference cylinder 203 can rotate freely. After the detection trolley 12 changes the detection position, it may stop on a slope, so that the detection trolley 12 is in an inclined state. During this process, the reference cylinder 203 always maintains a vertical state under the gravity of itself and the internal water, that is, the reference cylinder 203 drives the adjacent rotating frame 202 to rotate along the fixed frame 201 (here, the change is taken as an example of rising), so that the detection trolley 12 is in an inclined state, and the detection trolley 12 is in an inclined state. Figure 2The direction is taken as an example, and the inspection vehicle 12 moves to the right in an uphill state as a reference for explanation). The rotating frame 202 drives the spur gear 301 to rotate clockwise, so that the spur gear 301 drives the rack frame 302 to slide to the left along the adjacent fixed frame 201. At the same time, the first elastic element 304 gradually extends, and the pressure sensor 303 detects a pressure decrease (when the inspection vehicle 12 is downhill, the spur gear 301 rotates counterclockwise, and the rack frame 302 slides to the right along the adjacent fixed frame 201. At this time, the first elastic element 304 is further compressed, and the pressure detected by the pressure sensor 303 increases). The data acquisition and processing unit 4 can determine the position of the inspection vehicle 1 according to the pressure change. 2, thereby controlling the robot arm 2 to deflect the electromagnetic induction detection unit 3, changing the receiving direction of the electromagnetic induction detection unit 3, so that the electromagnetic induction detection unit 3 is always vertical to the ground, and improving the detection accuracy. When the position of the electromagnetic induction detection unit 3 is adjusted, the electromagnet 404 is turned off, so that the second elastic element 402 drives the plug shaft 401 to reset, and the rack frame 302 is limited, and the reference cylinder 203 is locked to improve the stability of the reference cylinder 203. Then, various parameters are set on the basis of the trimming to detect the grounding grid. After the detection is completed, the reference vehicle 11 and the detection vehicle 12 are spliced. When the above situation occurs again, repeat the above steps.

[0045] In a further embodiment, Figure 7 and Figure 8 As shown, it also includes: a vibration component, which has two components and is respectively arranged on two rotating frames 202, for causing the reference cylinder 203 to vibrate, and the vibration component includes: a connecting frame 501, which has several components and is fixedly connected to the outside of the reference cylinder 203, and the connecting frame 501 is slidably connected to several knocking shafts 502 that fit adjacent reference cylinders 203, and a third elastic element 503 is arranged between the knocking shaft 502 and the adjacent connecting frame 501; a power component, which is arranged on the rotating frame 202, and is used to drive the knocking shaft 502 to move.

[0046] In the above scheme, there are two connecting frames 501, which are symmetrically distributed outside the reference cylinder 203, and the fixed positions of the reference cylinder 203, the connecting frame 501 and the rotating frame 202 are staggered to avoid the center of the reference cylinder 203 from being offset, causing the reference cylinder 203 to be unable to be in a vertical state. The third elastic element 503 is a tension spring, which is used to drive the adjacent knocking shaft 502 to knock on the outer wall of the reference cylinder 203, thereby causing the reference cylinder 203 to vibrate due to the knocking, so that the water droplets attached to the inner wall of the reference cylinder 203 gather inside, thereby avoiding inaccurate liquid level of the water in the reference cylinder 203.

[0047] Specifically, such as Figure 7 and Figure 8As shown in the drawings, the power assembly includes a first motor 504 fixedly connected to the rotating frame 202, a spline shaft 505 fixedly connected to an output shaft of the first motor 504, and an extrusion block 506 spline-connected to the spline shaft 505 for pushing the adjacent knocking shaft 502 to move.

[0048] In the above scheme, the extrusion block 506 is composed of a circular ring and two right-angled triangular blocks, and the long straight edges of the triangular blocks are attached to the circular ring. The adjacent knocking shaft 502 is extruded by the hypotenuse of the triangular blocks, so that the third elastic element 503 is charged. The extrusion block 506 is externally provided with a wear-resistant coating, such as a nickel coating, to reduce friction loss and prolong service life.

[0049] Specifically, as shown in the drawings, Figure 7 and Figure 8 The displacement assembly includes a second motor 601 fixedly connected to the rotating frame 202, a lead screw 602 fixedly connected to an output shaft of the second motor 601, and a push block 603 threadedly connected to the lead screw 602, the push block 603 being limitingly and slidingly connected with the extrusion block 506.

[0050] In the above scheme, the lead screw 602 and the push block 603 are made of high-strength steel, having certain structural strength. In the initial state, the push block 603 and the two knocking shafts 502 at the top of the adjacent reference cylinder 203 are at the same height. The lead screw 602 intermittently drives the push block 603 to move downward, and the distance of each movement is the distance between the two adjacent knocking shafts 502. By knocking the outer wall of the reference cylinder 203 from top to bottom, the reference cylinder 203 is vibrated, and the water attached to the inner wall of the reference cylinder 203 slides downward under the action of vibration, avoiding the attachment of water droplets on the inner wall of the reference cylinder 203, which causes the liquid level sensor 205 to fail to detect the actual change of the liquid level, thereby reducing the detection accuracy of the grounding grid.

[0051] After the position of the detection vehicle 12 changes, the liquid level of the water in the reference cylinder 203 will change. The change in the liquid level will cause some water to remain on the inner wall of the reference cylinder 203, thereby causing the liquid level detected by the liquid level sensor 205 to be inaccurate. When the reference cylinder 203 is locked, the liquid level sensor 205 will detect the liquid level in the adjacent reference cylinder 203, and then turn on the first motor 504, so that the output shaft of the first motor 504 drives the spline shaft 505 to rotate, and the spline shaft 505 drives the extrusion block 506 to rotate synchronously. The squeezing block 506 rotates and squeezes the two adjacent knocking shafts 502, causing the knocking shafts 502 to slide along the adjacent connecting frame 501. At this time, the third elastic element 503 is stretched. When the squeezing block 506 is separated from the adjacent knocking shaft 502, the third elastic element 503 drives the adjacent knocking shaft 502 to reset and knock on the outer wall of the adjacent reference cylinder 203, causing the reference cylinder 203 to vibrate. The water attached to the inner wall of the reference cylinder 203 slides downward under the action of the vibration, and the second motor 601 is turned on at the same time. The output shaft of 1 drives the lead screw 602 to rotate, and the lead screw 602 drives the push block 603 to move downward (the distance of the push block 603 moving downward is determined by the change in the water level in the reference cylinder 203 detected by the liquid level sensor 205), so that the push block 603 drives the extrusion block 506 to move downward intermittently, so that the extrusion block 506 squeezes the knocking shaft 502 from top to bottom in sequence until the extrusion block 506 moves above the liquid level in the reference cylinder 203, and then turns off the first motor 504, and makes the second motor 601 rotate in the opposite direction, and the lead screw 60 After the pushing block 603 drives the squeezing block 506 to reset to its initial state, the second motor 601 is turned off, and the outer wall of the reference cylinder 203 is struck from top to bottom in sequence, so that the vibration drives the water droplets attached to the inner wall downward. The water droplets slide downward under the vibration and gather in the water inside the reference cylinder 203, thereby preventing the water droplets from adhering to the inner wall of the reference cylinder 203, causing the liquid level sensor 205 to be unable to detect the actual liquid level change, thereby reducing the grounding grid detection accuracy. When the detection vehicle 12 changes position again, the above steps are repeated.

[0052] In a further embodiment, Figures 1-8 As shown, a nondestructive testing method for a lightning protection grounding network, using the above-mentioned nondestructive testing device for a lightning protection grounding network, includes the following steps: Step 1: Move the device to the detection position of the grounding grid to be detected, and control the robotic arm 2 to drive the electromagnetic induction detection unit 3 to the top of the grounding grid, so that the axes of the transmitting coil and the receiving coil are strictly perpendicular to the main direction of the grounding grid; Step 2: Turn on the high-frequency signal generator and receiving coil. The transmitting coil is used to generate an alternating magnetic field. This magnetic field penetrates the ground and acts on the grounding grid, causing the grounding grid to generate an induced current and a secondary magnetic field. The receiving coil is responsible for capturing this secondary magnetic field signal. Step 3: The data acquisition and processing unit 4 analyzes and calculates the secondary magnetic field signal captured by the receiving coil, and accurately calculates the corresponding parameter change amount, such as the increase amplitude of the resistance and the change value of the inductance, thereby providing a quantitative basis for the performance evaluation of the grounding grid; Step 4: For the suspected problem area found in the preliminary detection, multiple repeated detections are required, and in each repeated detection, the magnetic induction detection unit 3 is translated in the horizontal direction or adjusted in height, and the current frequency of the transmitting coil is changed to obtain detection signals at different angles and depths.

[0053] The above is only the preferred specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacements or changes within the technical range disclosed by the present application according to the technical solution and the inventive concept of the present application, which should be covered within the protection scope of the present application.

Claims

1. A nondestructive testing device for a lightning protection grounding network, characterized in that: Includes: Mobile trolley (1); A robotic arm (2) fixedly connected to the mobile vehicle (1); An electromagnetic induction detection unit (3) is fixedly connected to the moving end of the robotic arm (2), the electromagnetic induction detection unit (3) being composed of a high-frequency transmitting coil and a receiving coil, the high-frequency transmitting coil being used to generate an induced current in the grounding grid, and the receiving coil being used to capture a magnetic field signal generated by the induced current in the grounding grid; A data acquisition and processing unit (4) is provided in the mobile vehicle (1) and is electrically connected to the electromagnetic induction detection unit (3). The data acquisition and processing unit (4) is used to calculate and analyze the magnetic field signal captured by the receiving coil.

2. A nondestructive testing device for a lightning protection grounding network according to claim 1, characterized in that: Also included are: A detection component is arranged in the mobile trolley (1) and is used to detect the change in the distance between the electromagnetic induction detection unit (3) and the grounding grid. The mobile trolley (1) is composed of a reference trolley (11) and a detection trolley (12), and the mechanical arm (2) is located on the detection trolley (12); The detection component includes: The fixed frame (201) has two fixed frames, which are respectively fixedly connected to the reference vehicle (11) and the detection vehicle (12); the fixed frame (201) is rotatably connected to a rotating frame (202); the rotating frame (202) is fixedly connected to a reference cylinder (203); the bottoms of the two reference cylinders (203) are fixedly connected and communicated with a connecting hose (204); the rotating frame (202) is fixedly connected to a liquid level sensor (205) for detecting the liquid level in the adjacent reference cylinders (203); and the fixed frame (201) is provided with a feedback component for detecting the tilt angle of the detection vehicle (12).

3. A nondestructive testing device for a lightning protection grounding network according to claim 2, characterized in that: The feedback component includes: A spur gear (301) fixedly connected to the rotating frame (202); A rack frame (302) is slidably connected to the fixed frame (201), and the spur gear (301) is meshed with the rack frame (302); A trigger component, arranged on the fixing frame (201), for detecting a displacement change of the rack frame (302); A locking assembly is provided on the fixed frame (201) and is used to lock the rotating frame (202).

4. A nondestructive testing device for a lightning protection grounding network according to claim 3, characterized in that: The trigger component includes: A pressure sensor (303) is fixedly connected to the fixing frame (201); The first elastic element (304) is arranged between the pressure sensor (303) and the rack (302).

5. A nondestructive testing device for a lightning protection grounding network according to claim 4, characterized in that: The locking assembly includes: An inserting shaft (401) is slidably connected to the fixing frame (201), and the inserting shaft (401) is used to limit the adjacent rack frame (302); A second elastic element (402) is provided between the insertion shaft (401) and the fixing frame (201); A driving assembly is provided on the fixing frame (201) and is used to drive the insertion shaft (401) to move.

6. A nondestructive testing device for a lightning protection grounding network according to claim 5, characterized in that: The drive assembly includes: A magnetic block (403) fixedly connected to the insertion shaft (401); An electromagnet (404) is fixedly connected to the fixing frame (201) and is used to absorb the magnetic block (403).

7. A nondestructive testing device for a lightning protection grounding network according to claim 6, characterized in that: Also included are: There are two vibration components, which are respectively arranged on the two rotating frames (202) and are used to make the reference cylinder (203) vibrate. The vibration components include: There are a plurality of connecting frames (501), all of which are fixedly connected to the outside of the reference cylinder (203); the connecting frames (501) are slidably connected to a plurality of knocking shafts (502) that fit adjacent reference cylinders (203); and a third elastic element (503) is provided between the knocking shaft (502) and the adjacent connecting frames (501); A power assembly is provided on the rotating frame (202) and is used to drive the striking shaft (502) to move.

8. A nondestructive testing device for a lightning protection grounding network according to claim 7, characterized in that: The power assembly includes: A first motor (504) fixedly connected to the rotating frame (202); A spline shaft (505) fixedly connected to the output shaft of the first motor (504); An extrusion block (506) is spline-connected to the spline shaft (505) and is used to push the adjacent striking shaft (502) to move; A position changing assembly is provided on the rotating frame (202) and is used to change the position of the extrusion block (506).

9. A nondestructive testing device for a lightning protection grounding network according to claim 8, characterized in that: The transposition component includes: A second motor (601) fixedly connected to the rotating frame (202); A lead screw (602) fixedly connected to the output shaft of the second motor (601); The push block (603) is threadedly connected to the lead screw (602), and the push block (603) is connected to the extrusion block (506) in a limited sliding manner.

10. A nondestructive testing method for a lightning protection grounding network, according to the nondestructive testing device for a lightning protection grounding network according to claim 9, characterized in that: The following steps are involved: Step 1: Move the device to the detection position of the grounding grid to be detected, and control the mechanical arm (2) to drive the electromagnetic induction detection unit (3) to the top of the grounding grid, so that the axes of the transmitting coil and the receiving coil are strictly perpendicular to the main direction of the grounding grid; Step 2: Turn on the high-frequency signal generator and receiving coil. The transmitting coil is used to generate an alternating magnetic field. This magnetic field penetrates the ground and acts on the grounding grid, causing the grounding grid to generate an induced current and a secondary magnetic field. The receiving coil is responsible for capturing this secondary magnetic field signal. Step 3: The data acquisition and processing unit (4) analyzes and calculates the secondary magnetic field signal captured by the receiving coil, and accurately calculates the corresponding parameter changes, such as the increase in resistance and the change in inductance, thereby providing a quantitative basis for the performance evaluation of the grounding grid; Step 4: For the suspected problem areas found in the preliminary detection, multiple repeated detections are required. During each repeated detection, the magnetic induction detection unit (3) is translated horizontally or adjusted in height to change the current frequency of the transmitting coil to obtain detection signals at different angles and depths.

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