CN108489981A - Electric branch three-dimensional configuration real-time detection apparatus - Google Patents

Abstract

A kind of electric branch three-dimensional configuration real-time detection apparatus, including：Rotation supporting module and the observation module being arranged on and high-pressure modular, high-pressure modular is stationary in detection process, and observation module rotates observation centered on high-pressure modular.The present invention can rotate observation module to shoot the electric branch section of different rotary angle while applying high voltage electric field, then the three-dimensional information of electric branch is restored by image procossing, realize the real-time observation to electric branch three-dimensional structure.

Description

Real-time detection device for three-dimensional shape of electrical dendrites

technical field

The invention relates to a technology in the field of detection of solid insulating materials, in particular to a real-time detection device for three-dimensional shape of electrical tree branches.

Background technique

Electric tree branches are one of the important factors leading to the failure of power cable insulation. At present, various research institutes have conducted extensive research on the initiation and growth characteristics of electrical dendrites in insulating materials under different conditions. The laboratory studies on the initiation and growth characteristics of electric dendrites mainly use the structure of pin-plate electrodes. There are two main observation methods: one is to slice the sample after the experiment and observe it with a microscope or other equipment; During the process, industrial cameras and other shooting equipment were used to observe the electric tree branches in real time. However, in fact, the electrical tree is a three-dimensional structure. The above two methods of observing the electrical tree both see the section of the electrical tree on the focal plane of the lens, and part of the information of the electrical tree will be lost.

Contents of the invention

Aiming at the disadvantages of the existing technology for observing three-dimensional electrical tree branches that can only be detected by CT observation of samples, real-time observation is impossible and the cost is high, the present invention proposes a real-time detection device for three-dimensional electric tree branches, which can rotate while applying a high-voltage electric field The cross-section of the electrical tree branch is photographed at different rotation angles, and then the three-dimensional information of the electrical tree branch is restored through image processing, so as to realize the real-time observation of the three-dimensional structure of the electrical tree branch.

The present invention is achieved through the following technical solutions:

The invention includes: a rotating support module, an observation module and a high-voltage module arranged on it, the high-voltage module is stationary during the detection process, and the observation module rotates and observes around the high-voltage module.

The high-voltage module includes: a high-voltage chamber, a needle electrode disposed inside the high-voltage chamber through a limiting device, and a ground electrode disposed in the high-voltage chamber through a grounding device, wherein: the needle electrode is connected to a high-voltage source outside the high-voltage chamber , the ground electrode is connected to the ground potential outside the high voltage cavity.

Both the high-pressure chamber and the sample to be tested are made of transparent materials.

A pressure equalizing ball is provided at the connection between the high pressure chamber and the high pressure source.

The sample to be tested is arranged between the needle electrode and the ground electrode, and the three are located on the central axis of the high pressure chamber. The needle electrode is inserted into the sample to be tested, and is pressed against the ground electrode by moving the limiting plate.

The ground electrode is connected to the ground potential through the ground wire, and the ground wire connects the ground electrode to the ground through the rubber plug under the cavity and the ground electrode jacket.

The observation module includes: a rotating frame and a light source mechanism and an observation mechanism respectively movably arranged at both ends thereof, wherein: the rotating frame is rotatably arranged on the rotating support module, and the light source mechanism and the observation mechanism are respectively arranged on opposite sides of the high-voltage module , during the experiment, the rotating frame rotates and drives the light source mechanism and the observation mechanism to surround the high-voltage module to divide the half circle into several shooting angles, and shoot the cross-sections of the samples to be tested passing through the center line at different angles, and then through image processing technology, different Perspective photographs of the three-dimensional structures of synthetic dimensional dendrites.

The above-mentioned activity settings, that is, the horizontal and vertical distances between the light source mechanism, the observation mechanism and the high-voltage module can be adjusted as required.

The observation mechanism includes: an industrial camera and an image processing module connected thereto, wherein: the industrial camera transmits the collected photos to the image processing module through a data line.

The rotating support module includes: a base, a pillar arranged on it, a tray and a driving mechanism, wherein: the pillar is connected to the observation module, the driving mechanism drives the observation module to rotate through a gear chain, and the tray is arranged on the top of the pillar and connected to the high-voltage module .

The drive of the gear chain is realized by the gears respectively arranged on the drive mechanism and the pillar and the chain connected with the gears.

Said driving mechanism adopts, but is not limited to, a motor.

technical effect

Compared with the prior art, the invention can realize the real-time observation of the three-dimensional structure of the electric dendrite. The invention rotates the observation device with the center line of the cylindrical sample as the axis, divides the semi-circle into several angles according to the preset rotation trajectory, and takes pictures of the electric branch sections at corresponding angles. The three-dimensional structure information of the electric tree can be obtained after processing and restoring the captured pictures. Corresponding the three-dimensional structure information of the electrical tree branch with time, the change rule of the three-dimensional shape of the electric tree branch with time can be obtained.

Description of drawings

Fig. 1 is a structural representation of the present invention;

In the figure: high voltage module 1, observation module 2, rotating support module 3;

Fig. 2 is a schematic structural diagram of a high voltage module;

In the figure: pressure equalizing ball 1-1, metal rod 1-2, high voltage line 1-3, upper cover 1-4, limit post 1-5, spring 1-6, moving limit piece 1-7, ground electrode jacket 1-8, ground electrode 1-9, needle electrode 1-10, sample to be tested 1-11, ground wire 1-12, cavity 1-13, rubber plug 1-14;

Figure 3 is a schematic diagram of the internal structure of the high voltage module;

Fig. 4 is the structural representation of observation module;

In the figure: support frame 2-1, vertical fixture 2-2, industrial camera 2-3, halogen lamp 2-4, horizontal fixture 2-5, rotating arm 2-6, industrial camera power cord 2-7, halogen lamp bracket 2-8, halogen lamp power line 2-9, battery 2-10, data line 2-11, image processing module 2-12;

Figure 5 is a schematic diagram of the structure of the rotating support module

In the figure: tray 3-1, pillar 3-2, bearing 3-3, battery box 3-4, chain 3-5, large gear 3-6, pinion 3-7, motor 3-8, base 3-9 , motor controller 3-10;

Fig. 6 is a schematic diagram of the motion track during the experiment of the observation module;

In the figure, each group of 4 photos is taken as an example to show the movement track of two groups of photos taken by the observation module in one cycle.

Detailed ways

As shown in FIG. 1 , this embodiment includes: a rotatable support module 3 , an observation module 2 and a high-voltage module 1 rotatably arranged on it.

As shown in Figure 2, the high-voltage module 1 includes: a pressure equalizing ball 1-1, a metal rod 1-2, a high-voltage line 1-3, an upper cover 1-4, a limit post 1-5, and a spring 1-6 , moving limit piece 1-7, ground electrode jacket 1-8, ground electrode 1-9, needle electrode 1-10, sample to be tested 1-11, ground wire 1-12, cavity 1-13 and rubber plug 1-14, wherein: the metal rod 1-2 is set in the insulating column above the upper cover 1-4, the pressure equalizing ball 1-1 is set on the metal rod 1-2, and the ground electrode 1-9 is set in the ground electrode jacket 1-8 and placed in the middle of the cavity 1-13, the needle electrode 1-10 is inserted into the sample 1-11 to be tested, the sample 1-11 to be tested is placed on the ground electrode 1-9, the needle electrode 1- The upper part of 10 is in contact with the moving limit piece 1-7, the moving limit piece 1-7 is set under the limit column 1-5 through the spring 1-6, and the limit column 1-5 is set on the upper cover 1-4 The bottom end of the needle electrode 1-10 and the sample to be tested 1-11 are pressed on the ground electrode 1-9 by the moving limit piece 1-7, and the high voltage line 1-3 connects the needle electrode 1-10 and the metal rod 1- 2. The metal rod 1-2 is connected to the high voltage source, the ground wire 1-12 connects the ground electrode 1-9 to the ground through the rubber plug 1-14 under the cavity 1-13 and the ground electrode jacket 1-8, and the limit column The center line of 1-5, spring 1-6, moving limiter 1-7, needle electrode 1-10, sample to be tested 1-11, and ground electrode 1-9 should coincide with the center line of cavity 1-13 , and the height should satisfy that when the sample to be tested 1-11 is set between the ground electrode 1-9 and the moving limiting piece 1-7, the spring 1-6 is in a compressed state, and the moving limiting piece 1-7 The upper cylinder is not completely lower than the lower surface of the limiting posts 1-5.

The cavity 1-13 is a cylindrical container without a cover, made of plexiglass.

The center of the bottom surface of the cavity 1-13 is provided with a number of cylindrical protrusions for fixing the position of the ground electrode 1-9; the center of the bottom surface of the cavity 1-13 is provided with a cylindrical depression , used to fix the position of the cavity 1-13 on the tray 3-1; a small hole is provided below the side of the cavity 1-13 for installing the rubber stopper 1-14.

The inner diameter of the upper cover 1-4 is the same as the outer diameter of the cavity 1-13, and there is a certain length of outer edge on the outside. The upper cover 1-4 is divided into two parts, the outer part is made of aluminum, and the inner part is made of aluminum. Polytetrafluoroethylene is used, and one side of the inner upper surface has an upward column for fixing the metal rod 1-2; the other side is provided with a through hole for passing the high-voltage line 1-3. There is a small cylindrical protrusion at the center of the inner lower surface of the upper cover 1-4, whose size matches the spring 1-6, and is used to fix the spring 1-6.

The ground electrode 1-9 is an aluminum cylinder, and the center of the bottom surface of the ground electrode 1-9 has a cylindrical depression whose size matches the protrusion on the bottom surface of the cavity 1-13, and is used to ground the ground electrode 1-9. The electrode 1-9 is just arranged at the center of the bottom surface of the cavity 1-13; the side of the ground electrode 1-9 is provided with a threaded hole for connecting the ground wire 1-12.

The ground electrode casing 1-8 is a polytetrafluoroethylene combination of a cylinder and a circular frustum. The inside of the ground electrode casing 1-8 is hollow, and its inner diameter matches that of the ground electrode 1-9. The height of the ground electrode jacket 1-8 is slightly higher than the ground electrode 1-9, so that when the sample 1-11 to be tested is placed on the ground electrode 1-9, the lower end will be fixed by the ground electrode jacket 1-8, and the ground electrode jacket 1-9 8. A through hole is provided on the side of the round platform part, and its position corresponds to the threaded hole on the side of the ground electrode 1-9, so as to pass the ground wire 1-12.

For the samples 1-11 to be tested, different insulating materials with better light transmittance are selected according to the experimental requirements. The sample 1-11 to be tested needs to be prepared as a cylinder, and its diameter should match the diameter of the ground electrode 1-9. The needle electrode 1-10 should be inserted in the center of the sample 1-11 to be tested.

The limiting column 1-5 is a hollow polytetrafluoroethylene cylinder, and one end of the limiting column 1-5 is arranged at the center of the inner lower surface of the upper cover 1-4. The inner diameter of the limiting post 1-5 matches the size of the spring 1-6, and the spring 1-6 is arranged inside the limiting post 1-5 and on the lower surface inside the upper cover 1-4.

The moving limiting piece 1-7 is made of polytetrafluoroethylene, including: an upper cylinder with a smaller diameter matching the size of the spring 1-6, matching the outer diameter of the limiting post 1-5 The lower cylinder with larger diameter.

The center of the lower surface of the lower cylinder is provided with a cylindrical depression whose size matches the needle electrodes 1-10.

The length of the spring 1-6 should be greater than the length of the limit post 1-5 when it is not stressed.

The observation module 2 includes: an industrial camera 2-3, a halogen lamp 2-4, a rotating arm 2-6, an industrial camera power cord 2-7, a halogen lamp bracket 2-8, a halogen lamp power cord 2-9, Battery 2-10, data cable 2-11, image processing module 2-12, two sets of supporting frames 2-1, horizontal clamp 2-5 and vertical clamp 2-2, wherein: industrial camera 2-3 passes through vertical clamp 2- 2 is set on the support frame 2-1, and the support frame 2-1 is further set on one end of the rotating arm 2-6 through the horizontal clamp 2-5; the halogen lamp 2-4 is set on the halogen lamp bracket 2-8, and the whole support is passed through The vertical clamp 2-2, the support frame 2-1 and the horizontal clamp 2-5 are arranged on the other end of the rotating arm 2-6, and the fixing method is similar to that of the industrial camera 2-3; the industrial camera 2-3 is connected through the industrial camera power cord 2- 7 is connected to the battery 2-10, and is connected to the image processing module 2-12 through the data line 2-11; the halogen lamp 2-4 is connected to the battery 2-10 through the halogen lamp power line 2-9.

The support frame 2-1 is a group of aluminum rectangular sheets with a rectangular through groove in the middle, and the height of the support frame 2-1 is preferably satisfied when the bottom end of the support frame 2-1 is arranged on the horizontal clamp 2-5. , the position of the upper end is higher than the needle electrodes 1-10.

The distance between two correspondingly arranged support frames 2-1 matches the width of the longitudinal clamp 2-2.

The halogen lamp bracket 2-8 includes: a halogen lamp base and a T-shaped bracket made of aluminum. The base of the halogen lamp is a rectangular aluminum plate whose width matches the distance between the two support frames 2-1. There is a threaded through hole in the middle for fixing the halogen lamp 2-4. There are 90° folded outer edges on both sides. A threaded through hole is provided along the top. The head of the T-shaped bracket is provided with a drill hole corresponding to the outer edge of the halogen lamp base for fixing the halogen lamp base, and the tail is provided with a through slot for setting the halogen lamp bracket 2-8 on the support frame 2-1 .

The structural difference between the vertical clamp 2-2 for fixing the industrial camera 2-3 and the vertical clamp 2-2 for fixing the halogen lamp 2-4 is that the vertical clamp for fixing the industrial camera is a rectangular aluminum block with a width equal to The distance between the two supporting frames 2-1 is matched, and a circular through hole is arranged in the middle, and its diameter is slightly larger than the lens diameter of the industrial camera 2-3. The vertical clamp is set on the support frame 2-1, and the industrial camera 2-3 is set in the vertical clamp 2-2; the vertical clamp for fixing the halogen lamp 2-4 includes a threaded rod and a nut, and the threaded rod runs through the support The through groove at the end of the frame 2-1 and the T-shaped bracket is fixed by a nut at the joint between the support frame 2-1 and the T-shaped frame.

The rotating arm 2-6 is a circular aluminum structure in the middle, the size matches the size of the battery box 3-4, and there are threaded drilling holes around it for connecting with the battery box 3-4. The center of the lower surface of the middle part of the rotating arm 2-6 is provided with a shallow groove matching the size of the smaller bearing 3-3, and the center of the middle part is provided with a circular through hole whose size matches the size of the uppermost stage of the pillar 3-2. match. Both sides of the swivel arm 2-6 are rectangular long rods protruding outwards, the length of which should be greater than the longest object distance of the industrial camera 2-3.

The horizontal clamp 2-5 is a rectangular aluminum block, and the middle part is provided with a rectangular through hole slightly larger than the long rod of the rotating arm 2-6. A threaded through hole is left on one side of the horizontal clamp 2-5, and the screw can be used to fix the The transverse clamp 2-5 is arranged on the long rod of the rotating arm 2-6. The upper surface of the transverse clamp 2-5 is provided with threaded drilling holes for fixing the support frame 2-1.

The rotary support module includes: tray 3-1, pillar 3-2, bearing 3-3, battery box 3-4, chain 3-5, large gear 3-6, pinion 3-7, motor 3- 8. The base 3-9, the motor controller 3-10, wherein: the pillar 3-2 and the motor 3-8 are set on the base 3-9, the tray 3-1 is set on the pillar 3-2, and the high voltage module 1 is set On the pallet 3-1, the bearing 3-3 has two sizes, large and small, and is placed on the steps of the pillar 3-2 respectively. The large bearing is connected with the large gear 3-6, and the small bearing is connected with the rotating arm 2-6 of the observation module , the battery box 3-4 is arranged on the big gear 3-6, the battery 2-10 for placing the observation module inside, the small gear 3-7 is arranged on the rotating shaft of the motor 3-8, and is connected with the chain 3-5 The large gear 3-6 is connected, and the motor 3-8 is connected with the motor controller. When the device is working, the motor 3-8 drives the large gear 3-6 to rotate, and then drives the battery box 3-4 and the entire observation module arranged on it 2 turn.

The material of the pillar 3-2 is made of aluminum, including: the lower part is a circular platform, and the upper part is a stepped three-stage cylindrical structure, wherein: the diameter of the uppermost cylindrical structure matches the inner diameter of the smaller bearing 3-3; The diameter of the cylindrical structure of the middle stage matches the inner diameter of the larger bearing 3-3 and is smaller than the outer diameter of the smaller bearing 3-3; the diameter of the cylindrical structure of the lowest stage is smaller than the outer diameter of the larger bearing 3-3 , that is, the two bearings 3-3 are respectively placed at the two steps of the pillar 3-2.

The rotating arm 2-6 is placed on the high bearing 3-3 and connected with the outer side of the bearing 3-3.

The lower surface of the bull gear 3-6 is provided with a shallow groove whose size matches the outer diameter of the lower bearing 3-3, and the center is provided with a through hole matching the diameter of the middle stage of the pillar 3-2, namely The bull gear 3-6 is placed on the lower bearing 3-3 and connected with the outer side of the bearing 3-3.

The device is tested in the following way: the ground electrode 1-9 is placed in the ground electrode casing 1-8, and placed in the center of the cavity 1-13. The sample to be tested 1-11 inserted into the needle electrode 1-10 is placed on the ground electrode 1-9. Put the ground wire 1-12 on the ground electrode 1-9 through the rubber plug 1-14 and the ground electrode jacket 1-8, and seal the rubber plug 1-14 with silicone rubber or epoxy glue. Add transformer oil or silicone oil into cavity 1-13 to make the oil level higher than needle electrode 1-10. Connect one end of the high voltage wire 1-3 to the needle electrode 1-10, and pass the other end through the through hole of the upper cover 1-4. Cover the upper cover 1-4 so that the movement limiting piece 1-7 is pressed against the upper end of the needle electrode 1-10. Connect the other end of the high-voltage line 1-3 to the metal rod 1-2, connect the metal rod 1-2 to the high-voltage circuit, and then connect the pressure equalizing ball 1-1.

Adjust the horizontal clamp 2-5 and the vertical clamp 2-2 so that the sample 1-11 to be tested is completely illuminated, the lens of the industrial camera 2-3 is on the same axis as the needle tip of the needle electrode 1-10, and the industrial The camera 2-3 focuses on a plane passing through the centerline of the sample 1-11 to be tested. Adjust the lens magnification of the industrial camera 2-3 so that the needle tip is magnified to the required magnification, and the image is clearly displayed on the image processing module 2-12. Lock the longitudinal clamp 2-2 and the horizontal clamp 2-5.

The rotation angle of the motor 3-8 is set according to the detection requirement, and the motor 3-8 is started. Motor 3-8 drives industrial camera 2-3 and all can stop for a short time after the angle of every rotation setting, industrial camera 2-3 takes pictures of the sample to be tested 1-11 of this angle at the time of stopping, and the photo is transmitted to image processing module 2-12. Motor 3-8 rotates by the locus shown in Figure 6, every half circle is a group. A group of pictures is restored with special image processing software to obtain the three-dimensional structure of the electrical tree in this group of time. Each subsequent group was treated in the same way to obtain the three-dimensional structure of the electrical dendrite as a function of time.

At the end of the test, after turning off the high-voltage source and fully short-circuiting the discharge, take out the sample 1-11 to be tested, observe the electric branch part of the test sample 1-11, and read out the actual size of the electric branch. Use the industrial camera 2-3 to observe the size in the software and compare it, and the ratio is the amplification factor of the cavity 1-13 and the sample 1-11 to be tested to the electric branch. The actual size of the three-dimensional electrical tree is obtained by dividing the previously obtained length and width of the three-dimensional electrical tree by the magnification factor.

The above specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principle and purpose of the present invention. The scope of protection of the present invention is subject to the claims and is not limited by the above specific implementation. Each implementation within the scope is bound by the invention.

Claims (9)

1. A real-time detection device for three-dimensional shape of electric branches, comprising: a rotating support module and an observation module and a high-voltage module arranged on it, the high-voltage module is stationary during the detection process, and the observation module is centered on the high-voltage module rotation observation; The observation module includes: a rotating frame and a light source mechanism and an observation mechanism respectively movably arranged at both ends thereof, wherein: the rotating frame is rotatably arranged on the rotating support module, and the light source mechanism and the observation mechanism are respectively arranged on opposite sides of the high-voltage module , during the experiment, the rotating frame rotates and drives the light source mechanism and the observation mechanism to surround the high-voltage module to divide the half circle into several shooting angles, and shoot the cross-sections of the samples to be tested passing through the center line at different angles, and then through image processing technology, different Perspective photographs of the three-dimensional structures of synthetic dimensional dendrites. 2. The device according to claim 1, wherein the high-voltage module comprises: a high-voltage cavity, a needle electrode set inside the high-voltage cavity through a limiting device, and a ground electrode set inside the high-voltage cavity through a grounding device. Electrodes, wherein: the needle electrode is connected to the high-voltage source outside the high-voltage chamber, the ground electrode is connected to the ground potential outside the high-voltage chamber, and the sample to be tested is arranged between the needle electrode and the ground electrode and the three are located on the central axis of the high-voltage chamber On the top, the needle electrode is inserted into the sample to be tested, and pressed against the ground electrode by moving the limit piece. 3. The device according to claim 2, characterized in that, the high-pressure chamber comprises: a chamber and an upper cover connected thereto, wherein: the center of the upper surface of the bottom surface of the chamber is provided with several The cylindrical protrusion of the ground electrode, the center of the lower surface of the bottom surface of the cavity is provided with a cylindrical depression for connecting the rotating support module, and a small hole is provided below the side of the cavity for installing a rubber plug; the inner diameter of the upper cover is the same as The outer diameter of the cavity is the same, and there is a certain length of outer edge on the outer side. The upper cover is divided into two parts, the outer part is made of aluminum, and the inner part is made of polytetrafluoroethylene. There is a cylinder on the inner upper surface for fixing metal rods. , the other side is provided with a through hole for passing high-voltage wires, and the center of the inner lower surface of the upper cover is provided with a cylindrical protrusion for fixing the spring. 4. The device according to claim 3, characterized in that a pressure equalizing ball is provided on the high pressure chamber, and the pressure equalizing ball is connected with the high pressure chamber through the metal rod. 5 . The device according to claim 2 , wherein the ground electrode is connected to the ground potential through a ground wire, and the ground wire connects the ground electrode to the ground through the rubber plug under the high-voltage cavity and the ground electrode jacket. 6. The device according to claim 3, wherein the observation mechanism includes an industrial camera and an image processing module, wherein: the industrial camera transmits the collected photos to the image processing module through a data line. 7. The device according to claim 1, wherein the rotating support module comprises: a base and a pillar, a tray and a drive mechanism arranged thereon, wherein: the observation module is connected with the gears and bearings on the pillar, The driving mechanism drives the observation module to rotate through the gear chain, and the tray is set on the top of the pillar and connected with the high-voltage module. 8. The device according to claim 7, wherein the support comprises: a circular platform and a stepped three-stage cylindrical structure arranged on it. 9 . The device according to claim 8 , wherein the gear chain drive is realized through gears respectively arranged on the drive mechanism and the pillar and a chain connected with the gears.