High-voltage in-service transmission line defect detection system and method based on helicopter inspection

Abstract

The present application discloses a high-voltage in-service transmission line defect detection system and method based on helicopter inspection, including a helicopter, an X-ray detection device, a control terminal, and a pull rope for connecting the X-ray detection device, wherein an electromagnetic release is provided at one end of the pull rope close to the X-ray detection device. The detection method includes the steps of determining the helicopter flight route, installing the equipment, hoisting the equipment, mounting the equipment, executing the detection, and taking the equipment offline. The present invention can realize fast, efficient, and safe live detection of transmission lines of any voltage, solving the problems of safety hazards in existing X-ray equipotential detection, low efficiency of tower access, and radiation damage.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage and ultra-high-voltage transmission line defect detection, and in particular to equipotential detection of transmission lines, and specifically to a high-voltage in-service transmission line defect detection system and method based on helicopter inspection. Background Art

[0002] Overhead transmission lines are the most important power equipment for long-distance transmission of electric energy, and they are characterized by high voltage and large current. During the operation of overhead transmission lines in my country, crimping-type power fittings must not only bear the full tension of the conductor or ground wire, but also act as conductors to pass current. Once installed, such fittings will not be disassembled. However, line drops and other phenomena often occur in overhead transmission lines, causing line accidents, which seriously affect the safe operation of transmission lines. After subsequent processing and analysis, it was mostly caused by the fact that the crimping operation of the tension clamp and the continuous tube did not comply with relevant regulations. Not only that, when the line is under heavy load operation, the tension clamp and continuous tube that do not meet the requirements of crimping are prone to cause local heating and excessive temperature, which may damage the conductor. Therefore, the crimping quality of the tension clamp seriously affects the safe operation of the transmission line.

[0003] In recent years, X-ray digital imaging detection technology has played an important role in the defect detection of transmission line hardware. It can quickly and accurately detect various structural defects of hardware such as tension clamps, joint pipes, drainage plates, and conductors. It is an important technical method to ensure the safe operation of the transmission network. However, due to the high requirements of live working on equipment and personnel, there are currently no mature X-ray live detection devices and related work instructions in China. X-ray detection of tension clamps is still generally limited to power outage operations or potential operations where workers are wearing shielding clothing. Multi-split transmission conductors are even more difficult to detect live due to technical difficulties such as small conductor spacing, incomplete capture of drainage line interference, and even the inability to place traditional detection devices due to the influence of the spacing of multi-split conductors, and the inability of detection devices to be compatible with conductors of different specifications.

[0004] Taking into account the problems of heavy live detection equipment, high risk of going up and down the tower, low efficiency, and great difficulty, a helicopter-based detection method has been disclosed. High-altitude live detection using helicopters as carriers avoids the danger of people going up and down the tower and coming into close contact with high voltage electricity. However, the only helicopter detection that has been put into use is based on image acquisition. Although this detection method is highly safe and efficient, its accuracy cannot be effectively controlled, especially for internal defects.

[0005] In view of this, there is a need for a detection device that can combine the efficient transportation of helicopters with X-ray detection technology in order to better achieve efficient detection. Summary of the invention

[0006] In order to solve the problem that the existing technology is not convenient for live detection of ultra-high voltage and high voltage transmission lines, the present application provides a high-voltage in-service transmission line defect detection system and method based on helicopter inspection, which can realize fast, efficient and safe live detection of transmission lines of any voltage, and solves the problems of safety hazards in existing X-ray and other potential detection, low efficiency in going up and down the tower, and radiation damage.

[0007] In order to achieve the above objectives, this application adopts the following technical solutions:

[0008] A high-voltage in-service transmission line defect detection system based on helicopter inspection includes a helicopter used for hoisting, moving and disassembling an X-ray detection device mounted on a high-voltage transmission line, wherein the end point of the helicopter wing is not less than 15 meters away from the nearest high-voltage transmission line and is located at a 45° direction from the nearest high-voltage transmission line; an X-ray detection device used for performing X-ray detection on live transmission lines, and acquiring and storing X-ray images for subsequent defect analysis; a control terminal that is communicatively connected to the X-ray detection device and is operated by personnel on the helicopter to control the working state and structural posture of the X-ray detection device; and a pull rope used to connect the X-ray detection device, wherein an electromagnetic release is provided on one end of the pull rope close to the X-ray detection device.

[0009] Preferably, the X-ray detection device includes a main frame for support and equipment installation, an X-ray machine and a detector are relatively installed on the main frame, a main control box for controlling the X-ray machine and the detector is detachably fixedly installed on the lower part of the main frame, a pair of hanging mechanisms are also installed on the main frame, and the left and right sides of any one of the hanging mechanisms are provided with an upper guide for guiding the detected ultra-high voltage cable into the hanging mechanism, and a lower guide installed on the main frame and located between the two hanging mechanisms, a smooth opening is formed between the upper guide and the lower guide for facilitating the sliding of the ultra-high voltage cable; a steering mechanism for controlling the rotation of the detector is also provided between the main frame and the detector, and the rotation angle range of the detector in the direction away from the X-ray machine is 1°-180°; and a hanger fixedly installed on the main frame for connecting to a helicopter.

[0010] Preferably, the steering mechanism comprises a support shaft with one end fixedly connected to the main frame, a plurality of spiral grooves are evenly distributed on the side wall of the support shaft, the spiral grooves extend axially from the free end face, the deflection angle of the starting point of any spiral groove in the radial plane of the support shaft is not less than 180°, a first sleeve is sleeved on the support shaft, a plurality of grooves for accommodating steel balls are arranged in the first sleeve, and the distribution positions of the grooves correspond one by one to any of the spiral grooves; any of the spiral grooves continues to extend axially near one end of the main frame to form a straight groove for clamping the first sleeve; the first sleeve is fixedly connected to a pillar, and the detector is mounted on the pillar; it also includes a driving mechanism rotatably arranged on the support shaft for driving the detector to rotate and move axially along the support shaft, and a stabilizing mechanism for maintaining the balance of the detector;

[0011] The wire hanging mechanism includes an L-shaped bracket fixedly mounted on the main frame, and a roller group mounted on the L-shaped bracket for hooking the UHV cable. The roller group consists of a plurality of coaxially mounted rollers, and each roller consists of an internal ceramic structure and an externally wrapped rubber structure.

[0012] Preferably, the driving mechanism comprises at least one bearing fixedly arranged on the supporting shaft, a servo motor is fixedly mounted on the outer ring of the bearing, the servo motor is drivingly connected to a screw rod, and the screw rod is threadedly connected to the support column.

[0013] Preferably, the stabilizing mechanism comprises at least one sliding sleeve fixedly connected to the outside of the first sleeve, a threaded sleeve fixedly connected to the outer wall of the bearing, the threaded sleeve fixedly connected to a guide rod, and the guide rod is slidably arranged in the sliding sleeve; there are two bearings, and two threaded sleeves are arranged on any bearing, and the guide rod is installed on any threaded sleeve, and the number and position of the sliding sleeves correspond to the guide rods.

[0014] Preferably, the upper guide is an integrally formed metal rod with a smooth surface, one end of which is fixedly connected to the main frame, and the other end is a free end. The fixed end is composed of a vertical section, a horizontal section, a first arc section and a second arc section connected in sequence. The projection of the wire hanging mechanism on the plane where the upper guide is located is within the range enclosed by the upper guide.

[0015] Preferably, the lower guide is formed by bending an integrally formed smooth metal rod, both ends of which are fixedly connected to the main frame. The lower guide includes a second straight section whose horizontal position is higher than the steering mechanism, and a first straight section whose horizontal position is lower than the steering mechanism.

[0016] The present invention also provides a method for detecting defects in high-voltage in-service transmission lines based on helicopter inspection, which is implemented according to the above-mentioned detection system and specifically includes the following steps:

[0017] Step STP100, determining the flight route: analyzing the electric field strength around the high-voltage transmission line under inspection through Anosft three-dimensional modeling, determining the safe electric field boundary according to the current transmission voltage, and determining the minimum safety distance and the best flight route;

[0018] Step STP200, equipment installation, reliably connect the X-ray device to the helicopter through the pull rope, and test the reliability of the electromagnetic release. After checking that it is correct, hoist it on the helicopter;

[0019] Step STP300, hoisting the equipment, taking half of the minimum safety distance as the length of the rope during initial hoisting, and hovering when the X-ray detection device reaches the area directly above the transmission line to be detected, and continuously releasing the rope to a safe length, and observing the rotation angle and swing amplitude of the X-ray detection device in the air;

[0020] If the rotation angle of the X-ray detection device is greater than 1 / 4 circle or the swing amplitude is greater than the span of the adjacent transmission line group of the detected transmission line within a single rotation cycle, the lifting is suspended;

[0021] If the rotation angle of the X-ray detection device is less than or equal to 1 / 4 circle or the swing amplitude is less than the span of the adjacent transmission line group of the detected transmission line within a single rotation cycle, the mounting is performed;

[0022] Step STP400, equipment mounting, the operator on the helicopter controls the steering mechanism to rotate the detector 180° to a position that is opposite to the working state; the helicopter aligns the smooth opening direction of the X-ray detection device with the high-voltage transmission line to be detected until the mounting is completed;

[0023] Step STP500, detection execution, the operator on the helicopter controls the steering mechanism 4 to rotate the detector 180° to the detection position of the initial position, and controls the X-ray machine through communication with the main control box according to the preset detection plan to execute the detection plan;

[0024] After completing the inspection of a certain position, the helicopter hovers, and the angle between the pull rope connected between the hovering position and the X-ray inspection device and the high-voltage transmission line is no more than 60°. After the helicopter hovers stably, the inspection personnel retract the pull rope. The single retraction distance is one displacement unit in the inspection plan until the transmission line inspection between the two towers is completed;

[0025] Step STP600, the equipment is offline, and the operator on the helicopter controls the steering mechanism to rotate the detector 180° and adjust it to a position away from the working state; the helicopter pulls the X-ray detection device diagonally upward in the direction away from the smooth opening until the X-ray detection device is offline and detached, and then the X-ray detection device is adjusted away, and the offline is completed.

[0026] Beneficial effects:

[0027] The present invention controls the deflection of the detector by arranging a steering mechanism, so that the detector can be in different positions during the line hanging stage and the monitoring stage, which can not only meet the openness required in the line hanging stage and make line hanging easier; at the same time, it can also improve the accuracy during the monitoring stage, so that the detector can be fully aligned with the X-ray machine to obtain high-quality X-ray imaging.

[0028] The present invention also further reduces the difficulty of the high-voltage transmission cable in the line hanging stage by providing an upper guide and a lower guide, can effectively improve the allowable mounting error range, makes the accuracy requirement of the line hanging operation lower, and can more quickly achieve effective line hanging of the detection device. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative labor.

[0030] Figure 1 It is a system schematic diagram of the present invention.

[0031] Figure 2 It is the axonometric drawing of the structure of the utility model.

[0032] Figure 3 yes Figure 1 Enlarged view of the structure of area A in the middle.

[0033] Figure 4 yes Figure 1 Another visual structural axonometric drawing.

[0034] Figure 5 yes Figure 1 main view.

[0035] Figure 6 yes Figure 4 Schematic diagram of the hanging line state.

[0036] Figure 7 This is a schematic diagram of the state where the detector is deflected 180°.

[0037] Figure 8 yes Figure 6 Enlarged view of the structure of area B in the middle.

[0038] Fig. 9 yes Figure 6 Axonometric drawing of .

[0039] Fig.10 This is a flow chart of Example 4.

[0040] In the figure: 1-main frame; 2-X-ray machine; 3-detector; 31-pillar; 4-steering mechanism; 41-servo motor; 42-screw; 43-first bushing; 44-sliding sleeve; 45-guide rod; 46-bearing; 47-threaded sleeve; 48-support shaft; 49-spiral groove; 5-main control box; 6-hanging mechanism; 61-L-shaped bracket; 62-roller group; 7-upper guide; 71-first arc segment; 72-second arc segment; 8-lower guide; 81-first straight segment; 82-second straight segment; 9-hanger. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0042] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0043] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0044] In the description of this application, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the application is usually placed when in use. It is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, if the terms "first", "second", etc. appear in the description of this application, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0045] In addition, if the terms "horizontal" or "vertical" appear in the description of this application, it does not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0046] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0047] Embodiment 1:

[0048] Combined with the instruction manual Figure 1-Figure 6 The high-voltage in-service transmission line defect detection system based on helicopter inspection shown includes a helicopter for hoisting, moving and disassembling an X-ray detection device mounted on a high-voltage transmission line, the end point of the helicopter wing being no less than 15 meters away from the nearest high-voltage transmission line and being located at a 45° direction from the nearest high-voltage transmission line; an X-ray detection device for performing X-ray detection on live transmission lines, acquiring and storing X-ray images for subsequent defect analysis; a control terminal, which is communicatively connected to the X-ray detection device and is operated by personnel on the helicopter to control the working state and structural posture of the X-ray detection device; and a pull rope for connecting the X-ray detection device, an electromagnetic release being provided on one end of the pull rope close to the X-ray detection device. The X-ray detection device includes a main frame 1 for support and equipment installation, an X-ray machine 2 and a detector 3 are relatively installed on the main frame 1, a main control box 5 for controlling the X-ray machine 2 and the detector 3 is detachably fixedly installed at the lower part of the main frame 1, a pair of hanging mechanisms 6 are also installed on the main frame 1, and the left and right sides of any one of the hanging mechanisms 6 are provided with an upper guide 7 for guiding the detected ultra-high voltage cable into the hanging mechanism 6, and a lower guide 8 is installed on the main frame 1 and located between the two hanging mechanisms 6, and a smooth opening is formed between the upper guide 7 and the lower guide 8 for facilitating the sliding of the ultra-high voltage cable; a steering mechanism 4 for controlling the rotation of the detector 3 is also provided between the main frame 1 and the detector 3, and the rotation angle range of the detector 3 in the direction away from the X-ray machine 2 is 1°-180°; and a hanger 9 fixedly installed on the main frame 1 for connecting to a helicopter.

[0049] Structure and working principle:

[0050] The working principle is basically the same as that of the existing X-ray detection device. Both of them establish communication with the main control box 5 through the terminal control device, emit X-rays through the X-ray machine 2, penetrate the high-voltage transmission cable arranged between the X-ray machine 2 and the detector 3, and form an image on the detector 3 to obtain a clear X-ray film of the high-voltage cable or hardware. By analyzing the X-ray film, the defects in the high-voltage transmission cable can be found, so as to carry out repairs and replacements in advance, avoiding the occurrence of huge economic losses caused by breakage or other power outages due to defects.

[0051] However, in order to highlight the application scenarios and technical effects of the structure of this embodiment, before explaining the structural principles, the applicant first makes necessary explanations on the existing X-ray detection methods for high-voltage transmission lines. The detection of high-voltage transmission lines is divided into power outage detection and live detection. As we all know, if power outage detection is used, its safety is fully guaranteed, at least in terms of ionizing radiation and the risk of electric shock. However, power outage detection is almost difficult to encounter in actual applications. The main reason is that the losses caused by power outages in high-voltage transmission lines and ultra-high voltage transmission lines are too huge and almost unbearable. Therefore, under normal circumstances, high-voltage transmission lines will not use power outage detection, so the research on power outage detection loses its meaning.

[0052] Well, in the field of live detection, it can generally be divided into equipotential detection and ground potential detection. First of all, let's explain ground potential detection. As the name implies, the potential of the target being detected and the detection personnel are not at the same potential, and there is a potential difference. Then this potential difference generally ranges from tens of kilovolts to hundreds of kilovolts. Therefore, the insulation protection of the detection personnel is very important, and the slightest leakage will lead to extremely serious consequences. Since the detection personnel are at ground potential, the current status, location, and accuracy of the detection cannot be observed intuitively, but because they are far away from high-voltage transmission cables, safety can be relatively guaranteed.

[0053] Finally, equipotential detection is when there is almost no potential difference between the inspector and the high-voltage line being inspected, that is, equipotential. The biggest advantage of this detection method is that the operator can clearly and directly perform X-ray detection on the transmission cables and hardware being inspected, and can quickly and accurately obtain high-quality X-rays; however, its advantages are very prominent, and its disadvantages are also obvious; because the operator is at the same potential as the high-voltage transmission line, at a close distance, despite more protection, he will be exposed to strong ionizing radiation, which is harmful to the health of the inspector.

[0054] Determine the flight route: Analyze the electric field strength around the high-voltage transmission line under inspection through Anosft 3D modeling, determine the safe electric field boundary according to the current transmission voltage, and determine the minimum safe distance and the best flight route;

[0055] Equipment installation: connect the X-ray device to the helicopter reliably through the pull rope, and test the reliability of the electromagnetic release. After checking that everything is correct, install it on the helicopter;

[0056] When lifting the equipment, take half of the minimum safety distance as the length of the rope for initial lifting. When the X-ray detection device reaches the area directly above the transmission line to be detected, it will hover and continue to release the rope to a safe length. Observe the rotation angle and swing amplitude of the X-ray detection device in the air.

[0057] If the rotation angle of the X-ray detection device is greater than 1 / 4 circle or the swing amplitude is greater than the span of the adjacent transmission line group of the transmission line being detected within a single rotation cycle, the lifting is suspended;

[0058] If the rotation angle of the X-ray detection device is less than or equal to 1 / 4 circle or the swing amplitude is less than the span of the adjacent transmission line group of the detected transmission line within a single rotation cycle, the mounting is performed;

[0059] The equipment is mounted. The operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° to a position that is opposite to the working state. The helicopter aligns the smooth opening direction of the X-ray detection device with the high-voltage transmission line to be detected until the mounting is completed.

[0060] During the detection, the operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° to the detection position of the initial position, and controls the X-ray machine 2 through communication with the main control box 5 according to the preset detection plan to execute the detection plan;

[0061] After completing the inspection of a certain position, the helicopter hovers, and the angle between the pull rope connected between the hovering position and the X-ray inspection device and the high-voltage transmission line is no more than 60°. After the helicopter hovers stably, the inspection personnel retract the pull rope. The single retraction distance is one displacement unit in the inspection plan until the transmission line inspection between the two towers is completed;

[0062] When the equipment is offline, the operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° and adjust it to a position away from the working state; the helicopter pulls the X-ray detection device diagonally upward in the direction away from the smooth opening until the X-ray detection device is offline, and then the X-ray detection device is moved away, and the offline is completed.

[0063] In view of the above detection, the detection device provided in this embodiment is mainly designed for helicopter live detection, and the specific principles are as follows:

[0064] The detection device provided in this embodiment is composed of three functional structures, namely:

[0065] The detection function structure consists of the main frame 1, the main control box 5, the X-ray machine 2 and the detector 3. The detection personnel establish communication with the main control box 5 and control the operation of the X-ray machine 2 and the detector 3 to obtain high-quality X-ray films for subsequent defect analysis. Since the X-ray machine 2 and the detector 3 are both installed on the fixed main frame 1, the distance between the two is matched in advance, and various parameters are set for high-voltage transmission lines, so very ideal X-ray films can be taken.

[0066] The mounting function structure, the mounting function, that is, the ability to mount the entire detection device on the high-voltage transmission line to be detected, is mainly undertaken by the hanging mechanism 6. Figure 2 The wire hanging mechanism 6 shown has multiple rollers for hanging wires. Since the overall center of gravity of the detection device is designed to be downward, the mounting point of the wire hanging mechanism 6 is basically at the highest position of the detection device. Therefore, no matter whether the high-voltage transmission line is a single-line design, a double-line design or a multi-split line design, effective mounting can be achieved, and balanced mounting can be achieved.

[0067] The guiding function structure, as a high-altitude detection operation, effectively installing the detection device on the high-voltage transmission line is a major difficulty in the detection work, and it is also a part of the work with a very high risk factor. Since the detection device itself has a large mass, usually ranging from more than ten kilograms to dozens of kilograms, therefore, the previous equipotential detection, just for the upper and lower towers of the detection device will take a lot of time, and invest a lot of manpower and time costs; especially for detection in remote mountainous areas, valleys, and canyon areas, the difficulty is unimaginable, the efficiency is extremely low, and the risk factor is high. The use of helicopter hoisting detection can fundamentally eliminate the problem of rugged terrain. It can even be said that the more rugged the terrain, the more the necessity and advantage of using helicopters or large-load drones can be reflected. However, due to high-altitude operations, how to effectively and accurately mount the detection device on the high-voltage transmission line is also a major problem. For this reason, the guiding function plays a vital role. Combined with Figure 2 , Figure 4-Figure 6 As shown in the upper guide 7 and the lower guide 8, the upper guide 7 wraps the outer contour of the hanging mechanism 6, and similarly, the lower guide includes the outer contour of the steering mechanism 4, so that when the trial hanging is carried out, even if the high-voltage transmission line is not accurately hung, under the guidance of the upper guide 7 and the lower guide 8, the transmission line is either in a completely detached state or in a completely mounted state, avoiding contact between the transmission line and other structural parts; at the same time, a smooth opening is formed between the upper guide 7 and the lower guide 8 to facilitate the sliding of the UHV cable, which can greatly improve the success rate of one-time hanging. Figure 6As shown, since the upper guide 7 has a movable free end, after the high-voltage cable is hung, under the gravity of the detection device itself, the high-voltage cable can be naturally hung on the hanging mechanism 6 and can be uninterruptedly slid back and forth on the high-voltage transmission line for detection according to the detection requirements. When the detection is completed, it is only necessary for the helicopter to apply an upward pulling force to the detection device through the hanger 9. At this time, the upper guide 7 returns to its initial position under the elastic force of its own deformation, and the auxiliary line is restored to the original position as shown in the figure. Figure 5 The current detection is now completed.

[0068] The steering mechanism 4, since the detector 3 needs to be aligned with the X-ray machine 2 when it is in the detection state, it is not conducive to hanging the line at this time, and the detector 3 may even block the normal hanging of the high-voltage line. Therefore, before hanging, the steering mechanism 4 needs to move the detector 3 from Figure 5 Status turns to Figure 7 state, so that the smooth opening is blocked above and below, and after the wire hanging is completed, the detector 3 is moved from Figure 7 Status turns to Figure 6 Status, start detection work.

[0069] Embodiment 2:

[0070] This embodiment is a further optimized design based on the embodiment 1, specifically combined with Figure 2-Figure 3 As shown, the steering mechanism 4 includes a support shaft 48 with one end fixedly connected to the main frame 1, and a plurality of spiral grooves 49 are evenly distributed on the side wall of the support shaft 48. The spiral groove 49 extends axially from the free end face, and the deflection angle of the starting point of any spiral groove 49 in the radial plane of the support shaft 48 is not less than 180°, that is to say, the rotation angle of any spiral groove 49 from the starting point to the end point cannot be less than 180°. The purpose of this arrangement is to ensure that the detector 3 can achieve an optimal 180° deflection, so as to make way for the hanging line to the greatest extent, improve the success rate of hanging line in one time, and reduce the obstacles to hanging line. The support shaft 48 is sleeved with a first sleeve 43, and the first sleeve 43 is provided with a plurality of grooves for accommodating steel balls, and the distribution positions of the grooves correspond one to one with any of the spiral grooves 49; the steel balls are used for two purposes: one is to ensure the smoothness of the rotation of the first sleeve 43 on the support shaft 48, that is, the smoothness of the deflection of the detector 3; the second is to strictly limit the abnormal deflection of the detector 3 through the spiral groove 49 to ensure that the deflection angle of the detector 3 is always in a precisely controllable state. The first sleeve 43 is fixedly connected to the pillar 31, and the detector 3 is mounted on the pillar 31; it also includes a driving mechanism rotatably arranged on the support shaft 48 for driving the detector 3 to rotate and move axially along the support shaft 48, and a stabilizing mechanism for keeping the detector 3 balanced.

[0071] In this embodiment, the driving mechanism includes at least one bearing 46 fixedly arranged on the support shaft 48, and a servo motor 41 is fixedly installed on the outer ring of the bearing 46. The servo motor 41 is driven and connected with a screw 42, and the screw 42 is threadedly connected with the support 31. Since the spiral groove 49 is a continuous spiral design, when the detector 3 needs to deflect at any angle, the steel ball will roll along the spiral groove 49, that is, a corresponding axial displacement will occur. However, the bearing 46 that fixes the servo motor 41 only allows the servo motor 41 to rotate axially with the detector 3, but cannot perform any axial displacement. Then, under this structure, if the detector 3 wants to achieve axial deflection, it must change the axial position relationship with the servo motor 41, which can only be achieved by rotating the screw 42, so as to achieve the advantage of high-precision controllability of the servo motor 41 to accurately control the deflection angle of the detector 3.

[0072] Further preferably, the stabilizing mechanism includes at least one sliding sleeve 44 fixedly connected to the outside of the first sleeve 43, a threaded sleeve 47 fixedly connected to the outer wall of the bearing 46, and a guide rod 45 fixedly connected to the threaded sleeve 47, and the guide rod 45 is slidably arranged in the sliding sleeve 44. The function of the guide rod 45 is to further enhance the stability of the detector 3 and reduce the lateral stress of the screw rod 42, so that the screw rod 42 only needs to bear the axial stress.

[0073] In order to improve the stability of the stabilizing mechanism and be compatible with bearings with smaller axial dimensions, preferably, there are two bearings 46, and two threaded sleeves 47 are provided on each bearing 46, and the guide rod 45 is installed on each threaded sleeve 47, and the number and position of the sliding sleeve 44 correspond to the guide rod 45.

[0074] As a further preferred structural setting of this embodiment, in order to improve the stability of the detector 3 in the working state, preferably, any of the spiral grooves 49 near the end of the main frame 1 continues to extend axially to form a straight groove for clamping the first sleeve 43, see Figure 8 As shown. The design of the straight groove is used to locate the stability of the working state of the detector 3. When the steel ball is in the spiral groove 49, although the detector 3 is subjected to stress under the axial stress of the screw rod 42, when the screw rod 42 further closes the distance between the pillar 31 and the servo motor 41 until the steel ball enters the straight groove, at this time, under the limiting effect of multiple steel balls, the pillar 31 will always be at the current angle and cannot be deflected, thereby relieving the stress of the screw rod 42 and the guide rod 45, making the structure more robust.

[0075] Embodiment 3:

[0076] This embodiment is a further optimized and improved design based on Embodiment 1 or Embodiment 2. Figure 6-Figure 9 As shown, in order to improve the ability of the helicopter to hang the detection device on the power transmission cable as quickly and efficiently as possible when hoisting the detection device, the problem of multiple operations required to effectively hang it due to obstruction by structural parts such as the X-ray machine 2 or the main frame 1 is avoided. Preferably, the upper guide 7 is formed by bending a metal rod with a smooth surface that is integrally formed, one end of which is fixedly connected to the fixed end on the main frame 1, and the other end is a free end, and the fixed end is composed of a vertical section, a horizontal section, a first arc section 71 and a second arc section 72 that are connected in sequence, and the projection of the hanging mechanism 6 on the plane where the upper guide 7 is located is within the range enclosed by the upper guide 7.

[0077] Furthermore, the lower guide 8 is formed by bending an integrally formed smooth metal rod, both ends of which are fixedly connected to the main frame 1. The lower guide 8 includes a second straight section 82 whose horizontal position is higher than the steering mechanism 4, and a first straight section 81 whose horizontal position is lower than the steering mechanism 4.

[0078] In order to meet the detection of multiple split transmission lines, preferably, the line hanging mechanism 6 includes an L-shaped bracket 61 fixedly mounted on the main frame 1, and a roller group 62 mounted on the L-shaped bracket 61 for hooking the ultra-high voltage cable. The use of the roller group 62 can adapt to the mounting of multiple split transmission lines of the current high-voltage transmission network. The mounting method of the roller group 62 has the advantages of high stability and strong adaptability, no adjustment is required, and the sliding is smooth.

[0079] Embodiment 4:

[0080] This embodiment provides a method for detecting defects in high-voltage transmission lines in service based on helicopter inspection. Figure 1 and Fig.10 As shown, it specifically includes the following steps:

[0081] Step STP100, determine the flight route: analyze the electric field strength around the high-voltage transmission line being inspected through Anosft three-dimensional modeling, determine the safe electric field boundary according to the current transmission voltage, and determine the minimum safety distance and the best flight route; for the method of determining the safe electric field boundary due to different voltage values ​​of high-voltage transmission lines, please refer to the simulation of the impact of patrol helicopters on the electric field of 500KV AC transmission lines recorded in the journal "High Voltage Technology" Volume 39, Issue 1, pages 201-209, which will not be described in detail in this application.

[0082] Step STP200, equipment installation, reliably connect the X-ray device to the helicopter through the pull rope, and test the reliability of the electromagnetic release. After checking that it is correct, hoist it on the helicopter;

[0083] Step STP300, hoisting the equipment, taking half of the minimum safety distance as the length of the rope during initial hoisting, and hovering when the X-ray detection device reaches the area directly above the transmission line to be detected, and continuously releasing the rope to a safe length, and observing the rotation angle and swing amplitude of the X-ray detection device in the air;

[0084] If the rotation angle of the X-ray detection device is greater than 1 / 4 circle or the swing amplitude is greater than the span of the adjacent transmission line group of the detected transmission line within a single rotation cycle, the lifting is suspended;

[0085] If the rotation angle of the X-ray detection device is less than or equal to 1 / 4 circle or the swing amplitude is less than the span of the adjacent transmission line group of the detected transmission line within a single rotation cycle, the mounting is performed;

[0086] Step STP400, equipment mounting, the operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° to a position that is opposite to the working state; the helicopter aligns the smooth opening direction of the X-ray detection device with the high-voltage transmission line to be detected until the mounting is completed;

[0087] Step STP500, detection execution, the operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° to the detection position of the initial position, and controls the X-ray machine 2 through communication with the main control box 5 according to the preset detection plan to execute the detection plan;

[0088] After completing the inspection of a certain position, the helicopter hovers, and the angle between the pull rope connected between the hovering position and the X-ray inspection device and the high-voltage transmission line is no more than 60°. After the helicopter hovers stably, the inspection personnel retract the pull rope. The single retraction distance is one displacement unit in the inspection plan until the transmission line inspection between the two towers is completed;

[0089] Step STP600, the equipment is offline, and the operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° and adjust it to a position away from the working state; the helicopter pulls the X-ray detection device diagonally upward in the direction away from the smooth opening until the X-ray detection device is offline and detached, and then the X-ray detection device is adjusted away, and the offline is completed.

[0090] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high-voltage in-service transmission line defect detection system based on helicopter inspection, characterized by: Including helicopters, used to hoist, move and disassemble X-ray detection devices mounted on high-voltage transmission lines, with the wing tip of the helicopter being no less than 15 meters away from the nearest high-voltage transmission line and located at a 45° direction to the nearest high-voltage transmission line; An X-ray detection device, used to perform X-ray detection on live transmission lines, and to obtain and store X-ray images for subsequent defect analysis; a control terminal, which is connected to the X-ray detection device in communication and operated by personnel on the helicopter to control the working state and structural posture of the X-ray detection device; and a pull rope for connecting the X-ray detection device, wherein an electromagnetic release is provided at one end of the pull rope close to the X-ray detection device; The X-ray detection device comprises a main frame (1) for supporting and installing the device, an X-ray machine (2) and a detector (3) are relatively mounted on the main frame (1), a main control box (5) for controlling the X-ray machine (2) and the detector (3) is detachably fixedly mounted on the lower part of the main frame (1), a pair of wire hanging mechanisms (6) are also mounted on the main frame (1), upper guides (7) for guiding the detected ultra-high voltage cable into the wire hanging mechanism (6) are arranged on the left and right sides of each of the wire hanging mechanisms (6), and a lower guide (8) is mounted on the main frame (1) and located between the two wire hanging mechanisms (6), a smooth opening is formed between the upper guide (7) and the lower guide (8) for facilitating the sliding of the ultra-high voltage cable; a steering mechanism (4) for controlling the rotation of the detector (3) is also arranged between the main frame (1) and the detector (3), the rotation angle range of the detector (3) in the direction away from the X-ray machine (2) is 1°-180°; and a hanger (9) fixedly mounted on the main frame (1) for connecting to a helicopter; The steering mechanism (4) comprises a support shaft (48) with one end fixedly connected to the main frame (1), a plurality of spiral grooves (49) are evenly distributed on the side wall of the support shaft (48), the spiral grooves (49) extend axially spirally from the free end surface, the deflection angle of the starting point of any spiral groove (49) in the radial plane of the support shaft (48) is not less than 180 degrees, the support shaft (48) is sleeved with a first sleeve (43), the first sleeve (43) is provided with a plurality of grooves for accommodating steel balls, the grooves are distributed The position corresponds to any one of the spiral grooves (49); any one of the spiral grooves (49) further extends axially at one end close to the main frame (1) to form a straight groove for clamping the first sleeve (43); the first sleeve (43) is fixedly connected to a support (31), and the detector (3) is mounted on the support (31); and further comprises a driving mechanism rotatably arranged on the support shaft (48) for driving the detector (3) to rotate and move axially along the support shaft (48), and a stabilizing mechanism for maintaining the balance of the detector (3); The cable hanging mechanism (6) comprises an L-shaped bracket (61) fixedly mounted on the main frame (1), and a roller group (62) mounted on the L-shaped bracket (61) for hooking the ultra-high voltage cable, wherein the roller group (62) is composed of a plurality of coaxially mounted rollers, and each roller is composed of an internal ceramic structure and an externally wrapped rubber structure.

2. The high-voltage in-service transmission line defect detection system based on helicopter inspection according to claim 1 is characterized in that: The driving mechanism comprises at least one bearing (46) fixedly arranged on the support shaft (48), a servo motor (41) being fixedly mounted on the outer ring of the bearing (46), the servo motor (41) being drive-connected to a screw rod (42), and the screw rod (42) being threadedly connected to the support column (31).

3. The high-voltage in-service transmission line defect detection system based on helicopter inspection according to claim 2 is characterized in that: The stabilizing mechanism comprises at least one sliding sleeve (44) fixedly connected to the outside of the first shaft sleeve (43), and a threaded sleeve (47) fixedly connected to the outer wall of the bearing (46); the threaded sleeve (47) is fixedly connected to a guide rod (45); the guide rod (45) is slidably arranged in the sliding sleeve (44); there are two bearings (46), and two threaded sleeves (47) are arranged on any bearing (46); the guide rod (45) is installed on any threaded sleeve (47); the number and position of the sliding sleeves (44) correspond to the guide rod (45).

4. The high-voltage in-service transmission line defect detection system based on helicopter inspection according to claim 3 is characterized in that: The upper guide (7) is formed by bending an integrally formed smooth metal rod, one end of which is fixedly connected to a fixed end on the main frame (1), and the other end is a free end, the fixed end being composed of a vertical section, a horizontal section, a first arc section (71) and a second arc section (72) connected in sequence, and the projection of the wire hanging mechanism (6) on the plane where the upper guide (7) is located is within the range enclosed by the upper guide (7).

5. The high-voltage in-service transmission line defect detection system based on helicopter inspection according to claim 4 is characterized in that: The lower guide (8) is formed by bending an integrally formed smooth metal rod, with both ends fixedly connected to the main frame (1). The lower guide (8) comprises a second straight section (82) whose horizontal position is higher than the steering mechanism (4), and a first straight section (81) whose horizontal position is lower than the steering mechanism (4).

6. A method for detecting defects in high-voltage transmission lines in service based on helicopter inspection, characterized in that: The detection system according to any one of claims 1 to 5 is implemented, specifically comprising the following steps: Step STP100, determining the flight route: analyzing the electric field strength around the high-voltage transmission line under inspection through Anosft three-dimensional modeling, determining the safe electric field boundary according to the current transmission voltage, and determining the minimum safety distance and the best flight route; Step STP200, equipment installation, reliably connect the X-ray device to the helicopter through the pull rope, and test the reliability of the electromagnetic release. After checking that everything is correct, hoist it onto the helicopter; Step STP300, hoisting the equipment, taking half of the minimum safety distance as the length of the rope during initial hoisting, and hovering when the X-ray detection device reaches the area directly above the transmission line to be detected, and continuously releasing the rope to a safe length, and observing the rotation angle and swing amplitude of the X-ray detection device in the air; If the rotation angle of the X-ray detection device is greater than 1 / 4 circle or the swing amplitude is greater than the span of the adjacent transmission line group of the transmission line being detected within a single rotation cycle, the lifting is suspended; If the rotation angle of the X-ray detection device is less than or equal to 1 / 4 circle or the swing amplitude is less than the span of the adjacent transmission line group of the detected transmission line within a single rotation cycle, the mounting is performed; Step STP400, equipment mounting, the operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° to a position that is opposite to the working state; the helicopter aligns the smooth opening direction of the X-ray detection device with the high-voltage transmission line to be detected until the mounting is completed; Step STP500, detection execution, the operator on the helicopter controls the steering mechanism (4) to rotate the detector (3) 180 degrees to the detection position of the initial position, and controls the X-ray machine (2) through communication with the main control box (5) according to the preset detection plan to execute the detection plan; After completing the inspection of a certain position, the helicopter hovers, and the angle between the pull rope connected between the hovering position and the X-ray inspection device and the high-voltage transmission line is no more than 60°. After the helicopter hovers stably, the inspection personnel retract the pull rope. The single retraction distance is one displacement unit in the inspection plan until the transmission line inspection between the two towers is completed; Step STP600, the equipment is offline, and the operator on the helicopter controls the steering mechanism 4 to rotate the detector 3 180° and adjust it to a position away from the working state; the helicopter pulls the X-ray detection device diagonally upward in the direction away from the smooth opening until the X-ray detection device is offline and detached, and then the X-ray detection device is adjusted away, and the offline is completed.

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