Optimization test method of pole-plate connection structure in pole tower and composite pole tower

Abstract

The present invention provides an optimization test method for the pole-plate connection structure in a pole tower and a composite pole tower, belonging to the technical field of optimizing electric field distortion near the connection point of a composite pole tower. The method comprises: preparing an initial simplified model of the pole-plate connection portion; subjecting the initial simplified model to artificial contamination treatment and then connecting it to an insulation performance test device; conducting a partial discharge test on the artificially contaminated initial simplified model to obtain actual test results; conducting a simulation calculation test on the initial simplified model, modifying model parameters based on the simulation test results and actual test results to obtain finite element simulation parameters; conducting a simulation calculation test on an improved model; when the simulation results of the improved model meet expected requirements, manufacturing the physical structure of the improved model; subjecting the improved model to artificial contamination treatment and partial discharge tests to obtain actual test results of the improved model; and determining the feasibility of the improved model based on the simulation test results and actual test results of the improved model.

Description

Technical Field

[0001] The present invention relates to the technical field of electric field distortion optimization near a composite material pole tower connection point, and in particular to an optimization test method for a pole-plate connection structure in a pole tower and a composite material pole tower. Background Art

[0002] In actual operation, composite towers need to withstand the tension of transmission lines, strong winds and other external environmental forces, and the various components need to be firmly connected, especially lattice-type composite insulation towers, which have many connection points and complex node connections. Figure 3 As shown, the two connecting rods are aligned at the connection point, a wide connecting plate is placed over the connection, and two metal bolts are used to secure the connecting rods to the wide connecting plate. Current practical research has found that when the tower surface is contaminated or damp, complex electrothermal processes may occur near the bolts. Under operating voltage, the metal bolts on the insulating tower become floating potential conductors, distorting the electric field distribution nearby and causing arc discharges, potentially impacting the mechanical connection and electrical insulation of the tower.

[0003] Many researchers have conducted extensive research on the principles and suppression measures for partial arc discharge on composite towers. They speculate that the discharge mechanism is related to the distortion of the electric field caused by the suspended potential metal. Finite element simulations have been used to analyze the electric field distortion characteristics of the suspended potential metal on the surface of the contamination layer. From the perspective of the electric field, the mechanism of corona discharge near the suspended metal has been explained. They have proposed voltage-equalizing measures to suppress discharge, such as improving the bolt shape, increasing the bolt curvature radius, and replacing metal protrusions on the tower with mortise and tenon joints. However, when conducting partial discharge tests after actual artificial contamination treatment, these measures were not ideal for suppressing partial arc discharge. Summary of the Invention

[0004] In view of this, the present invention provides an optimization test method for the rod-plate connection structure in a pole tower and a composite pole tower, improves the optimization test scheme for the rod-plate connection structure, and proposes an improvement scheme for the rod-plate connection part in the composite pole tower.

[0005] The technical solution adopted by the embodiment of the present invention to solve the technical problem is:

[0006] An optimization test method for a pole-plate connection structure in a pole tower, comprising:

[0007] Step S1, making an initial simplified model of the pole-plate connection part in the composite pole tower;

[0008] Step S2, subjecting the initial simplified model to artificial contamination treatment and then connecting it to an insulation performance test device, conducting a partial discharge test simulating partial discharge conditions at the connection between the composite tower and the plate using the initial simplified model after artificial contamination treatment, and obtaining an actual infrared temperature image of the contamination layer of the initial simplified model;

[0009] Step S3, performing an electrothermal coupling simulation calculation test on the insulating surface of a suspended potential metal conductor on the initial simplified model to obtain electrothermal parameter distribution simulation data of the initial simplified model, and optimizing model parameters based on the electrothermal parameter distribution simulation data of the initial simplified model and an actual infrared temperature image of the pollution layer of the initial simplified model to obtain final optimized parameters of the electrothermal coupling simulation calculation test;

[0010] Step S4, proposing a virtual structure of an improved model based on the defects shown in the actual infrared temperature image of the pollution layer of the initial simplified model, performing the simulation calculation test on the improved model based on the final optimization parameters, and obtaining electrothermal parameter distribution simulation data of the improved model;

[0011] Step S5, when the electrothermal parameter distribution simulation data of the improved model meets the preset requirements, manufacturing the physical structure of the improved model according to the virtual structure of the improved model, wherein the specification ratio of the physical structure of the improved model is the same as that of the physical structure of the initial simplified model;

[0012] Step S6, performing the artificial contamination treatment and the partial discharge test on the physical structure of the improved model to obtain an actual infrared temperature image of the contamination layer of the improved model;

[0013] Step S7, judging whether the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model;

[0014] Step S8: If the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model, the improved model is feasible.

[0015] Preferably, the step of performing artificial contamination treatment on the initial simplified model in step S2 includes:

[0016] Step S21, treating the initial simplified model as a test sample, cleaning the surface of each part of the test sample with anhydrous ethanol and deionized water to remove oil stains, placing it in a dustproof container, and allowing the surface of the test piece to be fully dried;

[0017] Step S22 , evenly brushing the artificial pollution suspension on the outer surface of the assembled sample to be tested, and after fully drying, obtaining the initial simplified model after the artificial pollution treatment.

[0018] Preferably, the insulation performance test device consists of a test transformer, a voltage regulator, a voltage and current acquisition system, and a spray chamber:

[0019] The mist chamber is composed of an organic glass reaction chamber, an ultrasonic mist generator, an insulating bracket, an exhaust fan and an infrared visible light imager. The insulating bracket is fixedly installed in the organic glass reaction chamber and is used to fix the test sample. The mist outlet pipe of the ultrasonic mist generator extends into the organic glass reaction chamber. The exhaust fan is installed on the side wall of the organic glass reaction chamber and is used to discharge water mist. The ultrasonic mist generator, the exhaust fan and the infrared visible light imager are all powered by an external power supply.

[0020] The input end of the test transformer is connected to an AC power supply, and the output end is connected to the voltage regulator. One output end of the voltage regulator is grounded, and the other output end is connected in series with a current-limiting resistor and then connected to the voltage and current acquisition system.

[0021] The voltage and current acquisition system is composed of a resistive voltage divider, a sampling resistor, an oscilloscope, and a computer. The first end of the resistive voltage divider is connected to the current-limiting resistor and the first connection end of the sample to be tested in the mist chamber. The second end of the resistive voltage divider is connected in series with the sampling resistor and then connected to the second connection end of the sample to be tested and to the ground terminal. The first connection end of the sample to be tested is connected to the current-limiting resistor by a wire, and the second connection end of the sample to be tested is connected to the sampling resistor and the first connection end of the oscilloscope by a wire. The second connection end of the oscilloscope is connected to the node between the two voltage-dividing resistors in the resistive voltage divider. The oscilloscope is connected to the computer via a data interface.

[0022] The infrared-visible-light imager integrates an infrared lens and a visible-light lens for synchronously acquiring an infrared temperature image and a visible-light image. The actual infrared temperature image of the pollution layer is a data superposition image of the infrared temperature image and the visible-light image.

[0023] Preferably, the parameters of the test transformer include a rated capacity of 15kVA, a rated input voltage of 220V, a rated output voltage of 50kV, and a rated output current of 0.3A; the parameters of the voltage regulator include a rated capacity of 20kVA, a rated input voltage of 220V, and a rated output voltage of 0-250V; the rated voltage of the resistive voltage divider is 100kV and the rated transformation ratio is 10000:1; the current limiting resistor is a deionized water resistor, and the resistance of the current limiting resistor is 35kΩ; The ultrasonic mist generator has a mist output rate of 300 mL / h; the diameter of the organic glass jar is 70 cm and the height is 50 cm; the exhaust fan is powered by a 12V DC power supply; the sampling resistor is a non-inductive resistor with a resistance of 55Ω; the sampling frequency of the oscilloscope is 1 kHz; the infrared temperature measurement range is -20°C to 800°C or -20°C to 100°C, the accuracy is ±1.5°C, the infrared resolution is 640×480, the frame rate is 9 Hz, and the visible light resolution is 5 Mp.

[0024] Preferably, the step S2 uses the initial simplified model after artificial pollution treatment to perform a partial discharge test to simulate the partial discharge situation at the connection part of the composite tower pole plate, and the actual infrared temperature image of the pollution layer of the initial simplified model is obtained, which includes:

[0025] Step S23, placing the initial simplified model after artificial pollution treatment as the test sample into the insulation performance test device, starting the ultrasonic mist generator to emit mist at a constant speed for humidification, and stopping the misting after the surface of the pollution layer is evenly moistened;

[0026] Step S24, applying a constant voltage method to pressurize the sample to be tested to 500V;

[0027] Step S25, collecting the leakage current of the sample to be tested in real time through the sampling resistor, imaging the leakage current waveform through the oscilloscope, and obtaining the leakage current waveform diagram;

[0028] Step S26, during the process of applying voltage to the test sample, collecting the infrared temperature image in real time by the infrared and visible light imager;

[0029] Step S27, analyzing the leakage current waveform to obtain a partial discharge time point when partial discharge occurs in the test sample, and capturing the visible light image at the partial discharge time point;

[0030] Step S28, after the discharge arc disappears, the voltage is reduced and the test ends. The basis for the disappearance of the discharge arc is that the amplitude of the leakage current is less than 100 μA;

[0031] Step S29 , synthesizing the infrared temperature image corresponding to the partial discharge time point and the visible light image to obtain an infrared temperature image of the pollution layer.

[0032] Preferably, step S3 performs an electrothermal coupling simulation calculation test on the insulating surface of a suspended potential metal conductor on the initial simplified model, and optimizes the model parameters based on the electrothermal parameter distribution simulation data of the initial simplified model and the actual infrared temperature image of the pollution layer of the initial simplified model, and the final optimized parameters of the electrothermal coupling simulation calculation test include:

[0033] Step S31, cutting and partitioning the actual infrared temperature image of the pollution layer of the initial simplified model, and establishing a temperature distribution matrix Te according to the temperature mean of each partition;

[0034] Step S32, performing electrothermal coupling simulation modeling on the initial simplified model; wherein, in the electrothermal coupling simulation modeling process, the partitions of the initial simplified model are defined according to the cropped partitions of the actual infrared temperature image of the pollution layer, the area where the arc channel is located is analyzed based on the visible light image to simulate a dry zone, and other parts of the area where the arc channel is located are defined as conductive thin layers to simulate a wet pollution layer, and an initial value is given for the conductivity of the partition located in the dry zone;

[0035] Step S33, performing finite element simulation on the initial simplified model to obtain initial electrothermal parameter distribution simulation data, performing data processing on the initial electrothermal parameter distribution simulation data and extracting a temperature distribution matrix Ts;

[0036] Step S34, calculate the function value of the objective function f:

[0037]

[0038] P=Aθ(EB)+Aφ(E+B)

[0039] E ij =Ts ij -Te ij i=1,2…,m;j=1,2…,n

[0040] Among them, E ij The error matrix P is the penalty function, A is the penalty function coefficient, B represents the error threshold matrix, θ represents the operation of finding the number of non-negative elements in the matrix, and Φ represents the operation of finding the number of non-positive elements in the matrix;

[0041] Step S35, determining whether the relative change of each objective function value in the most recent m correction cycles is less than the tolerance 1e-6; if so, executing step S38; if not, executing step S36;

[0042] Step S36, taking the conductivity as an optimization object, adjusting the conductivity to change the current density in the finite element simulation;

[0043] Step S37, based on the adjusted conductivity matrix, returning to execute steps S33 to S35;

[0044] Step S38, the optimization ends, and the current conductivity matrix is ​​selected as the final optimization parameter.

[0045] Preferably, the initial simplified model is formed by connecting two composite rods and a square plate via two metal bolts, wherein the metal bolts are conventional hexagonal bolts, and the distance between the two composite rods at the connection portion is d;

[0046] According to the material of the connecting piece between the two composite rods, the types of rod-plate connections are divided into composite plate-rod connection type and metal plate-rod connection type. The composite plate-rod connection type means that the material of the connecting piece is a composite material, and the metal plate-rod connection type means that the material of the connecting piece is a metal material.

[0047] The discharge parts of the initial simplified model of the composite plate rod connection type are the front and rear metal bolts and the composite plate rod connection point of the composite rod and the square plate. The improved model proposed for the initial simplified model of the composite plate rod connection type consists of two composite rods, two rounded rectangular plates and two hexagonal circular metal bolts. The connection end of the composite rod is rounded. A bolt hole is respectively provided at the center of the two rounded corners of the rounded rectangular plate. The two rounded rectangular plates are arranged opposite to each other. The connection ends of the two composite rods are placed between the two rounded rectangular plates with a spacing of d. The hexagonal circular metal bolts and the adapter nuts fix the composite rod and the two rounded rectangular plates at the bolt holes. The rounded rectangular plates are made of composite materials, have the same width as the composite rod, and have the same thickness as the square plate.

[0048] The discharge locations of the initial simplified model of the metal plate-rod connection type are the rear metal bolts and the connection points between the composite rod and the metal plate rod of the square plate. The improved model proposed for the initial simplified model of the metal plate-rod connection type consists of two composite rods, a metal sleeve and two metal bolts. The connecting ends of the two composite rods are respectively inserted from the openings at both ends of the metal sleeve with a spacing of d. The inner wall of the metal sleeve is in contact with the outer surface of the composite rod. The metal sleeve and the composite rod are fixedly connected by the metal bolts and the adapter nut. The thickness of the metal sleeve is the same as that of the square plate.

[0049] Preferably, the preset requirements are:

[0050] Taking temperature and current density as comparison objects, the electrothermal parameter distribution simulation data of the improved model are lower than the electrothermal parameter distribution simulation data of the initial simplified model.

[0051] Preferably, the step S7 determines whether the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model:

[0052] The error matrix between the temperature distribution matrix Te corresponding to the actual infrared temperature image of the pollution layer of the improved model and the temperature distribution matrix Ts corresponding to the electrothermal parameter distribution simulation data of the improved model is less than the error threshold.

[0053] The present invention also provides a composite pole tower. According to the material of the connector between composite poles at the same connection position, the pole-plate connection type of the composite pole tower is divided into a composite plate pole connection type and a metal plate pole connection type. The composite plate pole connection type means that the material of the connector is a composite material, and the metal plate pole connection type means that the material of the connector is a metal material.

[0054] The connection part of the composite plate rod connection type in the composite pole tower is composed of two composite rods, two rounded rectangular plates and two hexagonal circular metal bolts. The connection end of the composite rod is rounded. A bolt hole is respectively provided at the center of the two rounded corners of the rounded rectangular plate. The two rounded rectangular plates are arranged opposite to each other. The connection ends of the two composite rods are placed between the two rounded rectangular plates with a spacing of d. The hexagonal circular metal bolts and adapter nuts fix the composite rod and the two rounded rectangular plates at the bolt holes. The rounded rectangular plates are made of composite materials and have the same width as that of the composite rod.

[0055] The metal plate rod connection type connection part in the composite pole tower consists of two composite rods, a metal sleeve and two metal bolts. The connection ends of the two composite rods are respectively inserted from the openings at both ends of the metal sleeve with a spacing of d. The inner wall of the metal sleeve is in contact with the outer surface of the composite rod. The metal sleeve and the composite rod are fixedly connected by the metal bolts and the adapter nut. The thickness of the metal sleeve is the same as that of the square plate.

[0056] The present invention aims to find an optimization test method and optimization measures for local discharge at the pole-plate connection point of a composite material pole tower by conducting an artificial contamination experiment, and to improve and optimize the structure of the contaminated insulating cross-arm pole-plate connection point in view of the dry-belt discharge state of the contaminated insulating cross-arm pole-plate connection point, thereby suppressing the local discharge phenomenon at the connection point, including improvement measures for the composite plate connection point and the metal plate connection point. First, an initial simplified model of the pole-plate connection part in the composite material pole tower is made; the initial simplified model is artificially contaminated and then connected to an insulation performance test device, and a local discharge test is performed using the initial simplified model after artificial contamination treatment to simulate the local discharge situation at the pole-plate connection part of the composite material pole tower, and the actual infrared temperature image of the pollution layer of the initial simplified model is obtained; the initial simplified model is subjected to a suspended potential metal conductor insulation surface electrothermal coupling simulation calculation test to obtain electrothermal parameter distribution simulation data of the initial simplified model, and the model parameters are optimized based on the electrothermal parameter distribution simulation data of the initial simplified model and the actual infrared temperature image of the pollution layer of the initial simplified model, and the final optimization parameters of the electrothermal coupling simulation calculation test are obtained; the actual infrared temperature image of the pollution layer of the initial simplified model is shown The defects of the improved model are solved by proposing a virtual structure. The improved model is simulated and tested based on the final optimized parameters to obtain the electrothermal parameter distribution simulation data of the improved model. When the electrothermal parameter distribution simulation data of the improved model meets the preset requirements, the physical structure of the improved model is manufactured according to the virtual structure of the improved model. The specifications and proportions of the physical structure of the improved model are the same as those of the physical structure of the initial simplified model. The physical structure of the improved model is artificially contaminated and subjected to partial discharge tests to obtain the actual infrared temperature image of the contamination layer of the improved model. It is judged whether the actual infrared temperature image of the contamination layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model. If the actual infrared temperature image of the contamination layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model, the improved model is feasible. An optimization test plan for the improved pole-plate connection structure is proposed, and an improvement plan for the pole-plate connection part of the composite pole tower is proposed. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 Flowchart of the test method for optimizing the pole-plate connection structure in a pole tower.

[0058] Figure 2 It is the principle diagram of the insulation performance test device.

[0059] Figure 3 This is a diagram illustrating the existing connection parts in composite towers.

[0060] Figure 4 It is a plan view of the improved model using parallel circular composite plates of the present invention.

[0061] Figure 5 It is a three-dimensional illustration of the improved model using parallel circular composite plates of the present invention.

[0062] Figure 6 It is a plan view of the improved model using a metal sleeve of the present invention.

[0063] Figure 7 It is a three-dimensional illustration of the improved model using a metal sleeve of the present invention.

[0064] Figure 8 This is a flow chart of the electrothermal coupling simulation test of the present invention.

[0065] Among them: test transformer 1; voltage regulator 2; current limiting resistor 3; ultrasonic mist generator 4; organic glass reaction chamber 5; exhaust fan 6; insulating bracket 7; resistive voltage divider 8; sampling resistor 9; oscilloscope 10; computer 11; infrared visible light imager 12; connecting plate (composite or metal) 13; metal bolt 14; connecting rod (composite) 15; connecting plate (composite) 16; hexagon socket round bolt 17; connecting rod (composite) 18; connecting plate (metal) 19; metal bolt 20; connecting rod (composite) 21. DETAILED DESCRIPTION

[0066] The technical solutions and technical effects of the present invention are further described in detail below with reference to the accompanying drawings of the present invention.

[0067] This invention optimizes the structure of composite pole connections in composite towers, combining actual partial discharge testing with simulation experiments. First, actual testing and modeling simulations are conducted using existing connection structures. Effective modeling parameters are obtained by modifying simulation parameters. The composite pole connection structure is structured through simulation experiments and verified through actual discharge tests. Therefore, by classifying the locations of partial discharge on composite towers, artificial contamination tests are conducted using small-scale attached metal flat plate specimens and pole-plate connection point models to simulate the connection points where discharge occurs on composite towers. Visible light images, infrared images, and leakage current are simultaneously observed during the discharge process, capturing the electrothermal characteristics of the dry band formed during the test. This supplements and improves research on arc discharges on insulating surfaces contaminated by attached suspended metal. Based on experimental results of the current density distortion characteristics of tower connection points, connection point optimization measures are proposed and verified experimentally using small-scale models, providing a theoretical and experimental basis for suppressing arc discharges near composite tower connection points.

[0068] The insulation performance test device for partial discharge test of the present invention is as follows Figure 2 As shown, it consists of a test transformer 1, a voltage regulator 2, a voltage and current acquisition system, and a spray chamber:

[0069] The mist chamber consists of an ultrasonic mist generator 4, an organic glass reaction chamber 5, an insulating bracket 7, an exhaust fan 6 and an infrared visible light imager 12. The insulating bracket 7 is fixedly installed in the organic glass reaction chamber 5 and is used to fix the test sample. The mist outlet pipe of the ultrasonic mist generator 4 extends into the organic glass reaction chamber 5. The exhaust fan 6 is installed on the side wall of the organic glass reaction chamber 5 and is used to discharge water mist. The ultrasonic mist generator 4, the exhaust fan 6 and the infrared visible light imager 12 are all powered by an external power supply.

[0070] The input end of the test transformer 1 is connected to an AC power supply, and the output end is connected to a voltage regulator 2. One output end of the voltage regulator 2 is grounded, and the other output end is connected in series with a current limiting resistor 3 and then connected to a voltage and current acquisition system.

[0071] The voltage and current acquisition system consists of a resistive voltage divider 8, a sampling resistor 9, an oscilloscope 10, and a computer 11. The first end of the resistive voltage divider 8 is connected to the current limiting resistor and the first connection end of the sample to be tested in the mist chamber. The second end of the resistive voltage divider 8 is connected in series with the sampling resistor and then connected to the second connection end of the sample to be tested and to the ground terminal. The first connection end of the sample to be tested is connected to the current limiting resistor 3 by a wire connection, and the second connection end of the sample to be tested is connected to the sampling resistor 9 and the first connection end of the oscilloscope 10 by a wire connection. The second connection end of the oscilloscope 10 is connected to the node between the two voltage dividing resistors in the resistive voltage divider 8. The oscilloscope 10 is connected to the computer 11 via a data interface.

[0072] The infrared visible light imager 12 integrates an infrared lens and a visible light lens for synchronously collecting infrared temperature images and visible light images. The data superposition of the infrared temperature image and the visible light image can form an actual infrared temperature image of the pollution layer.

[0073] In terms of working parameters, the parameters of the test transformer include rated capacity of 15kVA, rated input voltage of 220V, rated output voltage of 50kV, and rated output current of 0.3A; the parameters of the voltage regulator include rated capacity of 20kVA, rated input voltage of 220V, and rated output voltage of 0-250V; the rated voltage of the resistive voltage divider is 100kV, and the rated transformation ratio is 10000:1; the current limiting resistor is a deionized water resistor with a resistance of 35kΩ; the mist output rate of the ultrasonic mist generator is 300mL / h; the diameter of the organic glass reaction chamber is 70cm and the height is 50cm; the exhaust fan is powered by a 12V DC power supply; the sampling resistor is a non-inductive resistor with a resistance of 55Ω; the sampling frequency of the oscilloscope is 1kHz; the measurement range of the infrared temperature is -20℃~800℃ or -20℃~100℃, the accuracy is ±1.5℃, the infrared resolution is 640×480, the frame rate is 9Hz, and the visible light resolution is 5Mp.

[0074] like Figure 1As shown, the optimization test method of the pole-plate connection structure in the pole tower provided by the present invention comprises the following steps:

[0075] Step S1, making an initial simplified model of the pole-plate connection part in the composite pole tower; the initial simplified model is as follows Figure 3 As shown, the initial simplified model consists of two composite rods and a square plate connected by two metal bolts. The metal bolts are conventional hexagonal bolts. At the connection part, the distance between the two composite rods is d.

[0076] Step S2, artificially contaminates the initial simplified model and connects it to an insulation performance test device, using the artificially contaminated initial simplified model to conduct a partial discharge test simulating partial discharge conditions at the connection between the composite tower and the plate, to obtain an actual infrared temperature image of the contamination layer of the initial simplified model;

[0077] Step S3, performing an electrothermal coupling simulation calculation test on the insulating surface of a suspended potential metal conductor on the initial simplified model to obtain electrothermal parameter distribution simulation data of the initial simplified model, and optimizing model parameters based on the electrothermal parameter distribution simulation data of the initial simplified model and an actual infrared temperature image of the pollution layer of the initial simplified model to obtain final optimized parameters of the electrothermal coupling simulation calculation test;

[0078] Step S4, proposing a virtual structure of an improved model based on the defects shown in the actual infrared temperature image of the pollution layer of the initial simplified model, performing simulation calculation tests on the improved model based on the final optimized parameters, and obtaining simulation data of the electrothermal parameter distribution of the improved model;

[0079] Step S5, when the electrothermal parameter distribution simulation data of the improved model meets the preset requirements, the physical structure of the improved model is manufactured according to the virtual structure of the improved model, and the specification ratio of the physical structure of the improved model is the same as that of the physical structure of the initial simplified model; the preset requirements here are: taking temperature and current density as comparison objects, the electrothermal parameter distribution simulation data of the improved model are lower than the electrothermal parameter distribution simulation data of the initial simplified model.

[0080] Step S6, performing artificial contamination treatment and partial discharge test on the physical structure of the improved model to obtain an actual infrared temperature image of the contamination layer of the improved model;

[0081] Step S7, determining whether the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model;

[0082] Step S8: If the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model, the improved model is feasible.

[0083] Specifically, the step of performing artificial contamination treatment on the initial simplified model in step S2 includes:

[0084] Step S21: The initial simplified model is regarded as a test sample, and the oil stains on the surface of each part of the test sample are cleaned with anhydrous ethanol and deionized water, and the sample is placed in a dustproof container to fully dry the surface of the test piece;

[0085] Step S22 , evenly apply the artificial pollution suspension on the outer surface of the assembled sample to be tested, and after sufficient drying, obtain an initial simplified model after artificial pollution treatment.

[0086] S2 uses the initial simplified model after artificial pollution treatment to simulate the partial discharge situation at the connection part of the composite tower plate. The actual infrared temperature image of the pollution layer of the initial simplified model is as follows:

[0087] Step S23: The initial simplified model after artificial pollution treatment is placed in an insulation performance test device as a test sample, and the ultrasonic mist generator is started to emit mist at a constant speed for humidification. The misting is stopped after the surface of the pollution layer is evenly moistened.

[0088] Step S24, applying a constant voltage method to pressurize the sample to be tested to 500V;

[0089] Step S25, collecting the leakage current of the sample to be tested in real time through the sampling resistor, imaging the leakage current waveform through the oscilloscope, and obtaining a leakage current waveform diagram;

[0090] Step S26, during the process of applying voltage to the sample to be tested, an infrared temperature image is collected in real time by an infrared visible light imager;

[0091] Step S27, analyzing the leakage current waveform to obtain the partial discharge time point when the test sample occurs partial discharge, and taking a visible light image at the partial discharge time point;

[0092] Step S28: After the discharge arc disappears, the voltage is reduced and the test ends. The disappearance of the discharge arc is based on the leakage current amplitude being less than 100 μA.

[0093] Step S29 , synthesizing the infrared temperature image corresponding to the partial discharge time point and the visible light image to obtain an infrared temperature image of the pollution layer.

[0094] Step S3 performs an electrothermal coupling simulation calculation test on the insulation surface of a suspended potential metal conductor on the initial simplified model, optimizes the model parameters, and obtains the final optimized parameters of the electrothermal coupling simulation calculation test, including:

[0095] Step S31, cutting and partitioning the actual infrared temperature image of the pollution layer of the initial simplified model, and establishing a temperature distribution matrix Te according to the temperature mean of each partition;

[0096] Step S32, performing electrothermal coupling simulation modeling on the initial simplified model; wherein, in the electrothermal coupling simulation modeling process, the partitions of the initial simplified model are defined according to the cropped partitions of the actual infrared temperature image of the pollution layer, the area where the arc channel is located is analyzed based on the visible light image to simulate a dry zone, and other parts of the area where the arc channel is located are defined as conductive thin layers to simulate a wet pollution layer, and an initial value is given for the conductivity of the partition located in the dry zone;

[0097] Step S33, performing finite element simulation on the initial simplified model to obtain initial electrothermal parameter distribution simulation data, performing data processing on the initial electrothermal parameter distribution simulation data and extracting a temperature distribution matrix Ts;

[0098] Step S34, calculate the function value of the objective function f:

[0099]

[0100] P=Aθ(EB)+Aφ(E+B) (2)

[0101] E ij =Ts ij -Te ij i=1,2…,m; j=1,2…,n (3)

[0102] Among them, E ij The error matrix P is the penalty function, A is the penalty function coefficient, B represents the error threshold matrix, θ represents the operation of finding the number of non-negative elements in the matrix, and Φ represents the operation of finding the number of non-positive elements in the matrix;

[0103] Step S35, determining whether the relative change of each objective function value in the most recent m correction cycles is less than the tolerance 1e-6; if so, executing step S38; if not, executing step S36;

[0104] Step S38, the optimization ends, and the current conductivity matrix is ​​selected as the final optimization parameter.

[0105] Refer to Figure 8As shown in the flowchart, the visible infrared light image observed synchronously with the partial discharge test is first processed for data. On the one hand, it is used to extract the infrared temperature distribution matrix Te, and on the other hand, it is used for graphic recognition and reconstruction to identify the dry zone model and build a finite element model. In the finite element model, the remaining wet dirt layer is first discretized, and then the model parameters and boundary conditions are set, and the optimization parameters are initialized. Here, the parameters refer to the conductivity matrix, and the initialization parameters are given values. Based on the initialization parameters, the simulation results after the finite element model simulation calculation are the electrothermal parameters. According to the electrothermal parameters, the simulated temperature distribution matrix Ts can be extracted, and the objective function about Ts and Te is specified. The optimization goal is to minimize the objective function. When the optimization goal is not achieved, the conductivity matrix is ​​corrected by modifying the particle position and velocity variables, and the electrothermal parameters are recalculated in the finite element model. The new simulated temperature distribution matrix Ts is calculated based on the recalculated electrothermal parameters for the objective function calculation. When the objective function result tends to a stable value, the optimization is stopped. The current conductivity is the final optimization parameter. The electrothermal parameters obtained from the simulation test according to the current conductivity are consistent with the actual infrared temperature image of the dirt layer.

[0106] In step S8, it is determined whether the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model: the error matrix E between the temperature distribution matrix Te corresponding to the actual infrared temperature image of the pollution layer of the improved model and the temperature distribution matrix Ts corresponding to the electrothermal parameter distribution simulation data of the improved model is obtained. ij Less than the error threshold, for example, the error threshold is set to 30K.

[0107] In the present invention, the types of rod-plate connections are divided into composite plate-rod connection type and metal plate-rod connection type according to the material of the connecting piece between the two composite rods. The composite plate-rod connection type refers to the material of the connecting piece being a composite material, and the metal plate-rod connection type refers to the material of the connecting piece being a metal material.

[0108] Reference Figure 3 The discharge locations of the initial simplified model of the composite plate-rod connection type are the front and rear metal bolts and the connection between the composite rod and the square plate. Therefore, the improved model proposed for the initial simplified model of the composite plate-rod connection type is Figure 4 and Figure 5 As shown, it consists of two composite rods, two rounded rectangular plates and two hexagonal circular metal bolts. The connecting end of the composite rod is rounded. A bolt hole is provided at the center of each rounded corner of the rounded rectangular plate. The two rounded rectangular plates are arranged opposite to each other. The connecting ends of the two composite rods are placed between the two rounded rectangular plates with a spacing of d. The hexagonal circular metal bolts and adapter nuts are used to fix the composite rods and the two rounded rectangular plates at the bolt holes. The rounded rectangular plates are made of composite material, have the same width as the composite rods, and have the same thickness as the square plates.

[0109] Reference Figure 3 The discharge locations of the initial simplified model of the metal plate-rod connection type are the rear metal bolts and the connection between the composite rod and the square plate. Therefore, the improved model proposed for the initial simplified model of the metal plate-rod connection type is Figure 6 and Figure 7 As shown, it consists of two composite rods, a metal sleeve and two metal bolts. The connecting ends of the two composite rods are respectively inserted from the openings at both ends of the metal sleeve with a spacing of d. The inner wall of the metal sleeve fits the outer surface of the composite rod. The metal sleeve and the composite rod are fixedly connected by metal bolts and adapter nuts. The thickness of the metal sleeve is the same as that of the square plate.

[0110] The present invention also provides a composite pole tower, characterized in that, according to the material of the connecting piece between the composite poles at the same connection position, the rod-plate connection type of the composite pole tower is divided into a composite plate rod connection type and a metal plate rod connection type. The composite plate rod connection type means that the material of the connecting piece is a composite material, and the metal plate rod connection type means that the material of the connecting piece is a metal material.

[0111] like Figure 4 and Figure 5 As shown, the connection part of the composite plate rod connection type in the composite pole tower consists of two composite rods, two rounded rectangular plates and two hexagonal circular metal bolts. The connection end of the composite rod is rounded. A bolt hole is provided at the center of each rounded corner of the rounded rectangular plate. The two rounded rectangular plates are arranged opposite to each other. The connection ends of the two composite rods are placed between the two rounded rectangular plates with a spacing of d. The hexagonal circular metal bolts and adapter nuts are used to fix the composite rods and the two rounded rectangular plates at the bolt holes. The rounded rectangular plates are made of composite materials and have the same width as the composite rods.

[0112] like Figure 6 and Figure 7 As shown, the connection part of the metal plate rod connection type in the composite pole tower consists of two composite rods, a metal sleeve and two metal bolts. The connecting ends of the two composite rods are inserted from the openings at both ends of the metal sleeve with a spacing of d. The inner wall of the metal sleeve fits the outer surface of the composite rod. The metal sleeve and the composite rod are fixedly connected by metal bolts and adapter nuts. The thickness of the metal sleeve is the same as that of the square plate.

[0113] The following is explained by specific examples:

[0114] First, establish and Figure 3 A model of the same size as the experimental model was used, and the outer surfaces of the rod and the plate were set as a conductive thin layer to simulate the wet dirt layer. The material parameters were directly assigned to the outer surface of the model. The thickness of the dirt layer was 0.5 mm, and the metal bolt 14 was a conventional hexagonal prism. The existing technology was simulated to obtain the simulation results.

[0115] Second, the electrothermal coupling simulation test of partial discharge optimization measures at the composite plate-rod connection point:

[0116] First, the experimental data of the initial simplified model of the composite plate-rod connection were analyzed. It was found that there was a local temperature rise near the metal bolts at the composite plate connection point and in the rod-plate connection area. The heating in the rod-plate connection area was the most severe, resulting in dry zone partial discharge. Therefore, to address the temperature and current density distortion at the rod-plate connection point, the composite plate width was changed to the same as the composite rod, the ends of the composite plate were rounded and chamfered, and hexagonal circular bolts 17 were used instead. Electrothermal coupling simulation experiments were conducted on the improved composite plate connection point, and the current density distribution at 4s was obtained. According to the simulation results, it was found that the improvement measures effectively improved the temperature and current density distribution in the rod-plate connection area, but increased the temperature and current density near the bolts. Therefore, to address the problem of increased temperature and current density near the bolts, the composite plates with equal widths were replaced with two parallel plates with hexagonal circular bolts connected to the composite rod. The composite rod was rounded, the electrothermal coupling simulation model was modified, and simulation experiments were conducted. According to the simulation results, the maximum current density near the hexagonal circular bolts 17 was reduced to 0.29A / m, and the volume current density of the fouling layer was equivalent to 580A / m2. The temperature and current density near the metal bolts at the composite plate connection points and at the rod-plate connection points were effectively reduced.

[0117] Third, electrothermal coupling simulation test of partial discharge optimization measures at metal plate-rod connection points

[0118] First, the initial simplified model test data of the metal plate-rod connection was analyzed, and it was found that there was a local temperature rise near the bolts at the rod-plate connection point and the back of the composite rod, and there was dry zone partial discharge. In order to solve the temperature and current density distortion problem of the bolts at the rod-plate connection point and the back of the composite rod, the width of the metal plate was changed to a metal sheath with a thickness of 2mm, which evenly wrapped the two composite rods. The same bolt connection was used, and an electrothermal coupling simulation model was established and a simulation experiment was carried out to obtain the surface current density distribution of the connection point at 4s. The simulation results show that the maximum current density of the metal connection plate is increased from 344A / m 2 Reduced to 271A / m 2 The maximum current density on the composite rod surface is reduced from 0.708A / m to 0.256A / m, which is equivalent to the volume current density in the contamination layer from 1416A / m 2 Reduced to 512A / m 2 The improvement measures of metal sleeves effectively improve the temperature and current density distribution near the rod-plate connection point and the bolts, and effectively suppress local discharge at the connection point.

[0119] The present invention proposes an optimization scheme for improving the rod-plate connection structure based on actual partial discharge tests and finite element simulation tests, and proposes improvements to the rod-plate connection structure of the prior art. For the composite rod-plate connection type, after adopting the improvement measure of parallel circular composite plates, the local heating phenomenon near the metal bolts basically disappears, the temperature distribution at the edge of the composite rod also becomes more uniform, and the rate of local temperature rise at the rod-plate junction is significantly reduced, effectively improving the temperature distribution at the connection point and suppressing the formation of dry bands and arc discharge. For the metal rod-plate connection type, after adopting the metal sleeve connection form, the temperature distribution on the surface of the composite rod becomes more uniform, the temperature rise rate of the fouling layer is also significantly reduced, effectively improving the temperature distribution at the connection point, and playing a role in suppressing the formation of dry bands.

[0120] The above disclosure is only a preferred embodiment of the present invention, and it is certainly not intended to limit the scope of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiment and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. An optimization test method for a pole-plate connection structure in a pole tower, characterized in that: include: Step S1, making an initial simplified model of the pole-plate connection part in the composite pole tower; Step S2, subjecting the initial simplified model to artificial contamination treatment and then connecting it to an insulation performance test device, conducting a partial discharge test simulating partial discharge conditions at the connection between the composite tower and the plate using the initial simplified model after artificial contamination treatment, and obtaining an actual infrared temperature image of the contamination layer of the initial simplified model; Step S3, performing an electrothermal coupling simulation calculation test on the insulating surface of a suspended potential metal conductor on the initial simplified model to obtain electrothermal parameter distribution simulation data of the initial simplified model, and optimizing model parameters based on the electrothermal parameter distribution simulation data of the initial simplified model and an actual infrared temperature image of the pollution layer of the initial simplified model to obtain final optimized parameters of the electrothermal coupling simulation calculation test; Step S4, proposing a virtual structure of an improved model based on the defects shown in the actual infrared temperature image of the pollution layer of the initial simplified model, performing the simulation calculation test on the improved model based on the final optimization parameters, and obtaining electrothermal parameter distribution simulation data of the improved model; Step S5, when the electrothermal parameter distribution simulation data of the improved model meets the preset requirements, manufacturing the physical structure of the improved model according to the virtual structure of the improved model, wherein the specification ratio of the physical structure of the improved model is the same as that of the physical structure of the initial simplified model; Step S6, performing the artificial contamination treatment and the partial discharge test on the physical structure of the improved model to obtain an actual infrared temperature image of the contamination layer of the improved model; Step S7, judging whether the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model; Step S8: If the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model, then the improved model is feasible; The initial simplified model consists of two composite rods and a square plate connected by two metal bolts. The metal bolts are conventional hexagonal bolts. At the connection part, the distance between the two composite rods is d. According to the material of the connecting member between the two composite rods, the rod-plate connection type is divided into a composite plate-rod connection type and a metal plate-rod connection type. The composite plate-rod connection type refers to the material of the connecting member being a composite material, and the metal plate-rod connection type refers to the material of the connecting member being a metal material. The discharge parts of the initial simplified model of the composite plate rod connection type are the front and rear metal bolts and the composite plate rod connection point of the composite rod and the square plate. The improved model proposed for the initial simplified model of the composite plate rod connection type consists of two composite rods, two rounded rectangular plates and two hexagonal circular metal bolts. The connection end of the composite rod is rounded. A bolt hole is respectively provided at the center of the two rounded corners of the rounded rectangular plate. The two rounded rectangular plates are arranged opposite to each other. The connection ends of the two composite rods are placed between the two rounded rectangular plates with a spacing of d. The hexagonal circular metal bolts and the adapter nuts fix the composite rod and the two rounded rectangular plates at the bolt holes. The rounded rectangular plates are made of composite materials, have the same width as the composite rod, and have the same thickness as the square plate. The discharge locations of the initial simplified model of the metal plate-rod connection type are the rear metal bolts and the connection points between the composite rod and the metal plate rod of the square plate. The improved model proposed for the initial simplified model of the metal plate-rod connection type consists of two composite rods, a metal sleeve and two metal bolts. The connecting ends of the two composite rods are respectively inserted from the openings at both ends of the metal sleeve with a spacing of d. The inner wall of the metal sleeve is in contact with the outer surface of the composite rod. The metal sleeve and the composite rod are fixedly connected by the metal bolts and the adapter nut. The thickness of the metal sleeve is the same as that of the square plate.

2. The optimization test method for the pole-plate connection structure in a pole tower according to claim 1, characterized in that: The step of performing artificial contamination treatment on the initial simplified model in step S2 includes: Step S21, treating the initial simplified model as a test sample, cleaning the surface of each part of the test sample with anhydrous ethanol and deionized water to remove oil stains, placing it in a dustproof container, and allowing the surface of the test piece to be fully dried; Step S22 , evenly brushing the artificial pollution suspension on the outer surface of the assembled sample to be tested, and after fully drying, obtaining the initial simplified model after the artificial pollution treatment.

3. The optimization test method for the pole-plate connection structure in a pole tower according to claim 2, characterized in that: The insulation performance test device consists of a test transformer, a voltage regulator, a voltage and current acquisition system, and a fog chamber: The mist chamber is composed of an organic glass reaction chamber, an ultrasonic mist generator, an insulating bracket, an exhaust fan and an infrared visible light imager. The insulating bracket is fixedly installed in the organic glass reaction chamber and is used to fix the test sample. The mist outlet pipe of the ultrasonic mist generator extends into the organic glass reaction chamber. The exhaust fan is installed on the side wall of the organic glass reaction chamber and is used to discharge water mist. The ultrasonic mist generator, the exhaust fan and the infrared visible light imager are all powered by an external power supply. The input end of the test transformer is connected to an AC power supply, and the output end is connected to the voltage regulator. One output end of the voltage regulator is grounded, and the other output end is connected in series with a current-limiting resistor and then connected to the voltage and current acquisition system; the voltage and current acquisition system is composed of a resistive voltage divider, a sampling resistor, an oscilloscope and a computer, the first end of the resistive voltage divider is connected to the current-limiting resistor and the first connection end of the sample to be tested in the fog chamber, the second end of the resistive voltage divider is connected in series with the sampling resistor and then connected to the second connection end of the sample to be tested and to the ground end; the first connection end of the sample to be tested is connected to the current-limiting resistor in a wire connection manner, the second connection end of the sample to be tested is connected to the sampling resistor and the first terminal of the oscilloscope in a wire connection manner, the second terminal of the oscilloscope is connected to the node between the two voltage-dividing resistors in the resistive voltage divider, and the oscilloscope is connected to the computer via a data interface; The infrared-visible-light imager integrates an infrared lens and a visible-light lens for synchronously acquiring an infrared temperature image and a visible-light image. The actual infrared temperature image of the pollution layer is a data superposition image of the infrared temperature image and the visible-light image.

4. The optimization test method for the pole-plate connection structure in a pole tower according to claim 3, characterized in that: The parameters of the test transformer include a rated capacity of 15kVA, a rated input voltage of 220V, a rated output voltage of 50kV, and a rated output current of 0.3A; the parameters of the voltage regulator include a rated capacity of 20kVA, a rated input voltage of 220V, and a rated output voltage of 0-250V; the rated voltage of the resistive voltage divider is 100kV and the rated transformation ratio is 10000:1; the current limiting resistor is a deionized water resistor, and the resistance of the current limiting resistor is 35kΩ; the ultrasonic The mist generator has a mist emission rate of 300 mL / h; the diameter of the organic glass reaction chamber is 70 cm and the height is 50 cm; the exhaust fan is powered by a 12V DC power supply; the sampling resistor is a non-inductive resistor with a resistance of 55Ω; the sampling frequency of the oscilloscope is 1 kHz; the measurement range of the infrared temperature is -20°C to 800°C or -20°C to 100°C, the accuracy is ±1.5°C, the infrared resolution is 640×480, the frame rate is 9 Hz, and the visible light resolution is 5 Mp.

5. The optimization test method for the pole-plate connection structure in a pole tower according to claim 4, characterized in that: The step S2 uses the initial simplified model after artificial pollution treatment to perform a partial discharge test simulating the partial discharge situation at the connection part of the composite tower pole plate, and obtains the actual infrared temperature image of the pollution layer of the initial simplified model, including: Step S23, placing the initial simplified model after artificial pollution treatment as the test sample into the insulation performance test device, starting the ultrasonic mist generator to emit mist at a constant speed for humidification, and stopping the misting after the surface of the pollution layer is evenly moistened; Step S24, applying a constant voltage method to pressurize the sample to be tested to 500V; Step S25, collecting the leakage current of the sample to be tested in real time through the sampling resistor, imaging the leakage current waveform through the oscilloscope, and obtaining the leakage current waveform diagram; Step S26, during the process of applying voltage to the test sample, collecting the infrared temperature image in real time by the infrared and visible light imager; Step S27, analyzing the leakage current waveform to obtain a partial discharge time point when partial discharge occurs in the test sample, and capturing the visible light image at the partial discharge time point; Step S28, after the discharge arc disappears, the voltage is reduced and the test ends. The basis for the disappearance of the discharge arc is that the amplitude of the leakage current is less than 100 μA; Step S29 , synthesizing the infrared temperature image corresponding to the partial discharge time point and the visible light image to obtain an infrared temperature image of the pollution layer.

6. The optimization test method for the pole-plate connection structure in a pole tower according to claim 5, characterized in that: The step S3 performs an electrothermal coupling simulation calculation test on the insulation surface of a suspended potential metal conductor on the initial simplified model, and optimizes the model parameters based on the electrothermal parameter distribution simulation data of the initial simplified model and the actual infrared temperature image of the pollution layer of the initial simplified model, and obtains the final optimized parameters of the electrothermal coupling simulation calculation test, including: Step S31, cutting and partitioning the actual infrared temperature image of the pollution layer of the initial simplified model, and establishing a temperature distribution matrix Te according to the temperature mean of each partition; Step S32, performing electrothermal coupling simulation modeling on the initial simplified model; wherein, in the electrothermal coupling simulation modeling process, the partitions of the initial simplified model are defined according to the cropped partitions of the actual infrared temperature image of the pollution layer, the area where the arc channel is located is analyzed based on the visible light image to simulate a dry zone, and other parts of the area where the arc channel is located are defined as conductive thin layers to simulate a wet pollution layer, and an initial value is given for the conductivity of the partition located in the dry zone; Step S33, performing finite element simulation on the initial simplified model to obtain initial electrothermal parameter distribution simulation data, performing data processing on the initial electrothermal parameter distribution simulation data and extracting a temperature distribution matrix Ts; Step S34, calculate the function value of the objective function f: P=Aθ(E ij -B)+Aφ(E ij +B) Yes ij =Ts ij -The ij ,i=1,2...,m;j=1,2...,n Among them, E ij is the error matrix, P is the penalty function, A is the penalty function coefficient, B is the error threshold matrix, θ is the operation of finding the number of non-negative elements in the matrix, and Φ is the operation of finding the number of non-positive elements in the matrix; Step S35, determining whether the relative change of each objective function value in the most recent m correction cycles is less than the tolerance 1e-6; if so, executing step S38; if not, executing step S36; Step S36, taking the conductivity as an optimization object, adjusting the conductivity to change the current density in the finite element simulation; Step S37, based on the adjusted conductivity matrix, returning to execute steps S33 to S35; Step S38, the optimization ends, and the current conductivity matrix is ​​selected as the final optimization parameter.

7. The optimization test method for the pole-plate connection structure in a pole tower according to claim 6, characterized in that: The preset requirements are: Taking temperature and current density as comparison objects, the electrothermal parameter distribution simulation data of the improved model are lower than the electrothermal parameter distribution simulation data of the initial simplified model.

8. The optimization test method for the pole-plate connection structure in a pole tower according to claim 7, characterized in that: The step S7 determines whether the actual infrared temperature image of the pollution layer of the improved model is consistent with the electrothermal parameter distribution simulation data of the improved model: The error matrix between the temperature distribution matrix Te corresponding to the actual infrared temperature image of the pollution layer of the improved model and the temperature distribution matrix Ts corresponding to the electrothermal parameter distribution simulation data of the improved model is less than the error threshold.

9. A composite material tower, applied to the optimization test method for the pole-plate connection structure in the tower according to any one of claims 1 to 8, characterized in that: According to the material of the connector between the composite rods at the same connection position, the rod-plate connection type of the composite pole tower is divided into a composite plate rod connection type and a metal plate rod connection type. The composite plate rod connection type means that the material of the connector is a composite material, and the metal plate rod connection type means that the material of the connector is a metal material; The connection part of the composite plate rod connection type in the composite pole tower is composed of two composite rods, two rounded rectangular plates and two hexagonal circular metal bolts. The connection end of the composite rod is rounded. A bolt hole is respectively provided at the center of the two rounded corners of the rounded rectangular plate. The two rounded rectangular plates are arranged opposite to each other. The connection ends of the two composite rods are placed between the two rounded rectangular plates with a spacing of d. The hexagonal circular metal bolts and adapter nuts fix the composite rod and the two rounded rectangular plates at the bolt holes. The rounded rectangular plates are made of composite materials and have the same width as that of the composite rod. The metal plate rod connection type connection part in the composite pole tower consists of two composite rods, a metal sleeve and two metal bolts. The connection ends of the two composite rods are respectively inserted from the openings at both ends of the metal sleeve with a spacing of d. The inner wall of the metal sleeve is in contact with the outer surface of the composite rod. The metal sleeve and the composite rod are fixedly connected by the metal bolts and the adapter nuts.

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