Transmission Line Tower Research Articles

Research on the linkage technology of electric power operation field video and Beidou high-precision positioning terminal

In order to adapt to the trend of intelligent development in power operation sites and solve practical problems such as inadequate supervision of traditional power operation sites, this article mainly studies the linkage technology between power operation site videos and Beidou high-precision positioning terminals. Based on the application scenarios of the BeiDou positioning system in power operations, this paper summarizes the linkage technology between on-site video and BeiDou high-precision positioning terminals in power operations, and concludes that this technology is suitable for safety control of personnel in power operation sites, inspection and supervision of power lines, monitoring and early warning of inclined and collapsed transmission line towers. Research has found that the linkage technology between on-site video of power operations and Beidou high-precision positioning terminals can promote the intelligent development of power operations and achieve higher precision on-site control of power operations.

Performance Study and Formulation Optimization of Rapid‐Curing Local Insulating Spray Coating Materials

With the increasing incidence of bird damage affecting the reliability of transmission lines, addressing bird pest control has become an important task for the operation and maintenance of transmission lines. A viable solution involves the application of spray‐coated polyurea elastomer composite materials to insulate exposed conductive points and weakly insulated connection parts of transmission line towers. To improve the comprehensive performance of polyurea elastomers, in this study, a polyurea curing system was modified by incorporating aluminum oxide (Al2O3), silicon dioxide (SiO2), and (boron nitride) BN nanoparticles. An orthogonal experiment was designed to investigate the influence of different fillers on the comprehensive performance of polyurea elastomers. These nanoparticles partially filled the defects inherent in the polyurea and BN microparticles, improving the alternating current (AC) breakdown strength of these elastomers. Compared with filler‐free polyurea elastomers, optimal performance of the polyurea elastomers was achieved when using 5 wt% Al2O3, 0.4 wt% SiO2, and 5 wt% BN, resulting in a 15.75% increase in the AC breakdown strength and a 10.00% enhancement in the thermal conductivity.

Projections of severe weather and the impacts on transmission line towers in Santa Catarina, Brazil, under future scenarios of global climate change

Transmission line towers are highly exposed to weather hazards. In southern Brazil, several damages to transmission lines have been reported due to severe weather events. Climate change projections indicate that the frequency and magnitude of extreme events may increase, making planning and adaptation of the transmission system exposure even more critical. In this work, we propose a severe weather index (SWI) as a proxy for detecting severe storms that can potentially result in extreme weather events. The SWI combines thresholds of instability indices based on observed severe events around the transmission tower-line systems. These indices were calculated using the downscaling by the Eta model at 20 km resolution of three global climate model projections and at 5 km of one global climate model for the historical period and the near future. The results show that the SWI captures the severe storms observed in the region. All downscaling projections agree with the increase of extreme weather events in the near future and the expansion of vulnerable areas. The constructed index can be employed to assess the risks and to plan the power transmission system better.

Rotation differential triboelectric nanogenerator for bird-repellent on transmission line towers

The security of transmission line towers is crucial to industrial development. Bird damage is a significant threat to transmission line towers in the field. However, the power supply to the bird-repellent devices is limited. In this work, we propose a rotation differential triboelectric nanogenerator (RD-TENG) to harvest wind energy for supplying electrical power to bird-repellent on transmission line towers. On the transmission line towers, the RD-TENG converts wind energy into electrical energy by rotation differential structure and stores power in a 1000 μF capacitor, then supplies power to the buzzer for bird-repellent. The device mainly consists of a wind cup, an input gear, output gears, and rotors. The RD-TENG can achieve double rotation speed by rotating the differential structure compared to the single gear counterpart, hence doubling the current and power output through triboelectric nanogenerator. The RD-TENG has a starting wind speed of 4 m s−1 and can operate normally at lower wind speeds. At a wind speed of 8 m s−1, the output performance of the RD-TENG is 830 V, 13.5 μA, 330 nC, and the peak power is 19.6 mW. This work realizes a new solution for bird-repellent on transmission lines through the TENG energy harvesting technique and also contributes to the subsequent smart grid construction.

A novel lifting point location optimization method of transmission line tower based on improved grey wolf optimizer

In the erection process of transmission line tower, the appropriate lifting point position is an important factor in ensuring the stability and balance of the lifting process and preventing deformation and damage to the towers. In this paper, a improved grey wolf optimization algorithm is proposed to solve the issues of low optimization efficiency and easily getting trapped in local minima when optimizing the lifting point position of transmission line towers. The improved algorithm includes the use of a good point-set strategy to enhance the initialization method of grey wolf individuals, ensuring a more uniform distribution of the population and reducing ineffective searches in the early stages of optimization. Furthermore, two random operators are utilized to combine and mutate the optimal grey wolf position, thereby enhancing the algorithm's ability to escape local optima. Finally, the trend information of the optimization process is considered, and the median value of the population is used to improve the stability of the optimization algorithm. Experimental results demonstrate that the proposed algorithm has better optimization performance and faster convergence speed compared to genetic algorithm, particle swarm optimization algorithm, and artificial fish swarm algorithm. It effectively addresses the optimization problem of lifting point position for transmission line towers.

Research on Corrosion Characteristics of Towers and Grounding Grids in Power Systems

Due to the increasingly severe corrosion of transmission line towers and grounding grids by the environment in which they are located, we analyse the corrosion characteristics of transmission line towers and grounding grids and provide a theoretical basis for the stable operation of the power grid. This article studies the corrosion components composed of various factors, including water content, temperature, potential difference, area ratio of the cathode to anode, and accelerated corrosion time, through experimental simulation of heavy industrial pollution environment. The research results indicate that water content, potential difference between positive and negative electrodes, area ratio of positive and negative electrodes, and test temperature significantly impact the accelerated corrosion rate test results.

Study on The Applicability of Drones in The Process of Forming Towers of 500KV Transmission and Substation Lines in Highland Areas

With the continuous development of science and technology in China, China's aviation field has also been expanding, the rapid development of aviation technology, China has gradually achieved leapfrog development in UAV equipment, and gradually tends to civilization, practicality and commercialization. At present, more and more UAVs are not only opening up in the domestic market, but also have flowed to overseas markets, and the modern advanced technology represented by UAVs has gradually become the current trend development trend. In the field of electric power engineering construction, the use of drone technology is short and wide, and there are drones in both high-altitude areas and plain areas. In terms of the engineering field, the UAV technology involves the construction, monitoring and management of power grids, fault and equipment maintenance of power grids and transmission line inspection, etc.

Visual Inspection Checklist For Concrete Structures (As A Part Of Structural Health Assessment)

Visual inspection of deteriorating reinforced concrete structures is an integral aspect of routine assessment practices. Data collected through visual inspection is primarily qualitative and subjective because it rarely involves. This article provides structural inspectors and facility engineers the methodology for visually inspecting any civil structure in a systematic way. The subject article is not prescribing any repair, retrofitting and rehabilitation methodologies. With help of basic design, technical and geographical information, inspectors can add value to the evaluation of deteriorated condition of structures. It is primarily for evaluating general civil structures, like buildings, retaining walls, transmission line towers, this study includes all the civil concrete structures, steel structures and pre-fabricated structures.

Research on Lightning Overvoltage Protection of Line-Adjacent Pipelines Based on Solid-State Decoupling

Existing transmission lines and pipelines are frequently crossed and erected in parallel, meaning that if lightning strikes a wire and causes insulator flashovers, the resulting lightning current will spread through the grounding of the tower where the flashover insulator is located. This dispersion of current can lead to overvoltage effects on nearby pipelines. This study performs simulation calculations to analyze the overvoltage experienced by pipelines due to the dispersion of grounding current from the tower. Furthermore, this paper proposes a method for protecting the pipeline from such an overvoltage. Firstly, the lightning transient calculation model of a transmission line tower is constructed using the electromagnetic transient software ATP-EMTP 5.5. The model calculates the effects of lightning peak currents and soil resistivity on the distribution characteristics of lightning current in the tower, specifically in the area where the flashover insulator is located. Subsequently, a calculation model of the tower grounding grid–natural gas pipeline is developed, taking into account the distribution characteristics of lightning current in the tower. This model analyzes the impact of lightning peak currents, soil resistivity, and pipeline spacing on pipeline overvoltage. Finally, the effectiveness of the solid-state decoupler in mitigating lightning overvoltage in the pipeline is verified. The results demonstrate a positive correlation between the lightning current entering the tower grounding grid through the flashover insulator and the lightning current distribution characteristics. The solid-state decoupling device proves to be effective in reducing the voltage of the pipeline insulation layer, and the simulation results provide the optimal laying length of the bare copper wire.

Failure Investigation of Transmission Line Towers with Unfilled Bolt Holes in Stub Member

Failure Investigation of Transmission Line Towers with Unfilled Bolt Holes in Stub Member

Stability Analysis of a Transmission Line Tower and Slope under Heavy Rainfall

In recent years, our country’s transmission lines have often been in danger due to geological disasters such as landslides when passing through fragile geological environments, which has brought great challenges and risks to the operation and maintenance of transmission lines. In order to understand the impact of transmission line towers on tower foundation slopes under heavy rainfall conditions, the influence of towers at different locations, rainfall intensities, and slopes on slope stability was analyzed by using Geo-Studio finite element analysis software. The results show that the slope has an important influence on the selection of the reasonable position of the tower. When the tower is located at the lower part of the slope, the safety factor of the slope is the highest. The safety factor of the slope is also reduced, and eventually the slope will be unstable and destroyed; the stability coefficient of the slope in the natural state is 1.221, which is in a stable state. Slopes are prone to overall sliding, with the spoil and overburden as the sliding body and the rock–soil contact surface as the sliding surface. This result provides a scientific basis for further understanding the influence mechanism of the slope angle at the location of the tower pole on this type of landslide under rainfall conditions. Further research can use the results of this paper as a benchmark to carry out corresponding experimental analysis and verification work.

Intelligent acceptance check for towers of overhead transmission line based on point clouds

AbstractThe acceptance check is a key step to decide whether an overhead transmission line can be put into use. However, for the acceptance check of towers, the manual means is still adopted mostly nowadays, which is dangerous and inefficient. The main challenges for intelligent check technique are the automatic tower segmentation and intelligent requirements of some detection items. Here, based on point clouds from lidars, some intelligent methods are proposed for tower related acceptance check items. The geometric structural changing rules for towers are found and analyzed to identify and segment towers from the scene point cloud automatically. A model‐constrained method is proposed for fine filtering of towers. With point cloud registration strategies, the tilt angle of a tower is calculated intelligently and the defect detection of a tower is conducted successfully. Experiments show that the results of the proposed methods are accurate, efficient and automatic, which have potential for real applications.

The 3D model construction method of overhead transmission line based on GIM

With the continuous progress of power grid digitization, Building Information Model (building information modeling, BIM) technology can no longer meet the application display requirements of power grid engineering. Power grid information model (grid information model, GIM) technology uses parameterization to build a 3D model, which reduces redundancy and is conducive to the digital transfer of the project. This paper briefly analyzes the structure of the GIM data model. It carries out research on 3D parametric modeling of overhead transmission line ground wire, tower, foundation, and insulator string based on GIM. It uses a 3D graphics engine to realize the visual rendering of ontology 3D models. On this basis, a 3D scene construction method of overhead transmission line engineering based on GIM is proposed, which provides reliable technical support for digital power grid applications.

Segmental instability failures in transmission line towers

This paper presents the results of the detailed studies conducted on premature failures of transmission line towers during full-scale testing. Configuration and proportioning of base width, hamper width, the height of each segment and selection of bracing patterns play a vital role in providing geometric stability to the tower. In the present study, three towers of different voltage clauses failed during testing, investigated and found that geometric instability caused the premature failure. In the case of a 500 kV tower with a rectangular configuration, the staggered bracing pattern continuously for multiple segments for about 20 m height without a diaphragm bracing in between caused geometric instability in the tower. Nonlinear FEA results of the tower modelled with diaphragm bracing showed that tower failure can be prevented by introducing diaphragm bracing at different heights. The 400 kV double circuit dead-end type tower with a 15 m height bottom segment and 161 kV suspension towers analysed based on the conventional static analysis ignoring geometric instability failed prematurely and FE analysis clearly shows the failure due to geometric instability. It is recommended to divide the single segment into two segments such that the included angle between the leg and primary bracing member can be increased, and thereby additional moments in the leg members are reduced by making the bracing member contribute to sharing the shear. The code recommended minimum included angle of 15° between the leg and primary bracing member is only a guiding parameter for the designers. Based on this study, it is recommended that the designers shall check the tower geometry for segmental / panel instability by modelling and nonlinear FE analysis of the tower with beam elements in place of conventional space truss elements.

Performance study of an epoxy–polythiol curing system for local insulating spraying based on the imbalance stoichiometric ratio

An epoxy–polythiol coating on a cross arm is an effective method to enhance the dielectric strength of air gaps in transmission line towers and reduce the occurrence of bird-related faults. However, epoxy–polythiol dual-component raw materials could not achieve the prescribed stoichiometric ratio of 1:1, affecting the protective performance of the formed insulation layer. This study characterizes the cured systems of epoxy–polythiol with imbalance stoichiometry using Fourier-transform infrared spectroscopy and scanning electron microscopy. Tests were conducted to analyze parameters of the epoxy–polythiol curing system, including breakdown strength, cure time, thermal conductivity, water absorption rate, and mechanical properties. Results demonstrate that nonstoichiometric conditions reduce the curing time, breakdown strength, thermal conductivity, and water absorption of the epoxy–polythiol curing system. However, a slight increase in the equivalent amount of the curing agent improves the mechanical properties of the cured products.

Cable-stayed towers in transmission lines

Electrical energy demand is increasing with development of country where cities become more urbanized. It is necessary more generator plants remaining efficient systems. Many of these plants can not be installed near cities and the importance of lines transmission is a fact. They are important as far as plants, because they are a part of all energy system. All distribution is done to distant sites in an economical way making the minimum of environmental impact. The paper deals with analysis of transmission lines in cable-stayed towers, involving details of the design of a transmission line tower where modeling process of the structure is performed by Tower, an auxiliary software for structural analysis. A good design is a pledge of good functioning of energy distribution. Load tests to evaluate the structures behavior are showed. Recurring faults as wind action, cables rupture, and cascade effect, which cause damage to operation of the line are showed. Optimization methods for structural calculus are suggested. Structural reliability studies in order to improve the design as a whole and avoid future failures are also suggested.

Numerical analysis of insulated and conventional cross arms for transmission line tower

The development of the world power industry has led to studies focused on high-performance materials to enhance the durability and prolong the service life of existing structures. In this context, cross arm is one of the main components of an electricity-transmission structure. The application of composite units (insulated cross arm) on lattice transmission towers was evaluated using the software Ansys 2020 R2 in terms of efficiency, cost, and mechanical performance, compared to conventional transmission towers. Finite-element analysis results demonstrated reductions in internal forces, displacements, and support reactions when the insulated cross-arm (IC) tower structure was employed instead of the conventional cross-arm (CC) tower structure. This could lead to minor structural costs. The IC tower exhibited a better stability under free vibrations owing to its higher stiffness than that of the CC tower. The main reason for these results was the height reduction proportioned by IC structures.

Parametric Analysis of Conductive Coupling of Transmission Line Tower Grounding and Pipeline in Multilayer Soil

Parametric Analysis of Conductive Coupling of Transmission Line Tower Grounding and Pipeline in Multilayer Soil

Research on Dynamic Characteristics Detection Method of Tall Power Transmission Tower

In addition to the gravity of the structure itself and the supported object, the open-air high-rise supported steel structure tower mainly bears dynamic loads. Take the transmission line tower as an example, such as wind load, conductor galloping, tower vibration and sudden unbalanced tension caused by line breaking. It is necessary to study the dynamic characteristic parameters to know the structural resistance to dynamic load. Therefore, from the perspective of dynamic safety evaluation, this paper designed the acquisition method of dynamic characteristic parameters and established a reliable finite element modal analysis model of transmission tower. Finally, the dynamic characteristic parameters such as natural frequency, vibration mode and amplitude of transmission line steel tower were obtained. It was found that the inclined material of the transmission tower might be unstable when the high-order natural frequency resonance occurred, which had important practical significance for structure design optimization and safety evaluation.

Modeling guyed towers of transmission lines in the assessment of backflashover occurrence

This paper evaluates the modeling of guyed towers of transmission lines in EMT-type programs to assess the backflashover occurrence of transmission lines and proposes a new modeling approach to be applied for this kind of towers. Two approaches to model the guyed towers by the revised Jordan model were evaluated: (i) the approach of CIGRE Brochure 63 that suggests representing the tower surge impedance as the parallel of the surge impedances of the mast and the guyed wires, ignoring the mutual coupling among them, and (ii) a new approach assuming the surge impedance of all the conductors in the tower section, guyed and mast conductors, including their mutual coupling effect. The evaluations considered the results provided by the Hybrid Electromagnetic Model (HEM) as reference for assessing the quality of the approaches. The approach (i) provided results of lightning overvoltage significantly lower than the reference, HEM model, leading to an underestimation of the probability of backflashover of the line. On the other hand, the approach (ii) was responsible for the results closest to those provided by HEM, indicating its quality, and the recommendation of applying this proposed approach for modeling guyed towers in the evaluations of backflashover occurrence.