Transmission Line Tower Research Articles

Static and Dynamic Analysis of Transmission Line Tower

The towers of the to the most powerful life-line buildings that support electrical transmission line are peculiar transmission. Transmission towers are essential for providing energy to various parts of the nation. The transmission line should be stable and carefully structured with the objective that they do not fizzle in the midst of a cataclysmic event and adapt to the national and universal standard. This present paper manages the investigation of static and dynamic examination of transmission line tower . A run of the mill sort of transmission line tower is picked as contextual analysis . The examination and displaying of pinnacle is done utilizing FE based ANSYS programming. The heaps following up on the pinnacle reflected are numb burden, live burden and dynamic burdens .in this Paper the most extreme twisting joined anxieties and characteristic frequencies ,bowing minute shear constrain are gotten.

Review of Failed Transmission Line Towers during Full Scale Testing

Towers are the most important component of the overhead power transmission line system. When failure occurs, direct and indirect losses are very high; hence accurate prediction of tower failure becomes very important for the reliability and safety of the transmission system. One cannot accurately predict the behavior of tower after practical loading conditions, so testing of tower for various loading conditions before installing in field becomes very important. The present paper discusses the structural behavior of towers during full scale testing carried out at Central Power Research Institute, Bangalore, India. Although, the towers were safe for various loading conditions based on the design/analysis, during full scale testing, different types of premature failures were observed. Necessary modifications in towers have been carried out and these towers were retested successfully. The details of remedial measures / strengthening of members carried out during testing are brought out in this paper.

Methodologies for Enhancing Durability of Transmission Line Tower Foundations

Methodologies for Enhancing Durability of Transmission Line Tower Foundations

A study of grounding arrangements composed by vertical electrodes for two-layered stratified soil models

This paper presents a study of a grounding arrangement proposed for transmission line (TL) towers, particularly for conditions of a stratified soil where the electric resistivity of the first layer is higher than the second medium. Techniques based on TL-theory are presented to estimate the harmonic grounding impedance of such configurations and are compared to the solution obtained with a rigorous electromagnetic (EM) method. The results show that the grounding resistance, important to low frequency frequency phenomena, and the impulse impedance, to fast transients, decrease significantly with the use of vertical electrodes. For a 230 kV TL, the critical towers can be improved by the proposed arrangement, which includes a significant economy of the conductor material applied to the grounding.

Uplift performance of helical piles with cement injection in residual soils

Helical piles have been widely used in Brazil to resist uplift forces of transmission line towers due to certain advantages compared with other foundations, such as resistance to both compressive and tensile loads, easy transport to remote sites, possibility of installation at batter angles, rapid installation with small equipment, and no need for concrete and formwork. However, in some sites the appropriate soil layer for the installation of the pile helices is too deep or too hard to be penetrated. In these cases, the use of helical foundations is not economically and (or) technically viable. One possible solution for this problem is to install the pile in a soil with low bearing capacity improved with cement injection. To evaluate the applicability of a soil-treatment method for helical piles, two different procedures of injection were tested in typical Brazilian residual soils of different geologic origin. For this investigation, 41 multi-helix piles (15 conventional piles and 26 with cement injection) were installed and submitted to tensile loading tests. The results reveal that both techniques can improve the tension capacity and produce a stiffer load–displacement response of helical piles under uplift loads.

Ultimate Lateral Bearing Capacity and Group Effect of Belled Wedge Pile Groups

Pile foundation of ports, high-voltage transmission line tower are subjected to amount of lateral loading, prediction on lateral bearing capacity is one of the most important projects in structure design. This paper pertains to the model tests on pile-soil interaction of single pile, 2 × 1 and 2 × 2 belled wedge pile groups embedded in sand under lateral load. The load versus displacement, and the soil pressures along depth surrounding piles are measured, the ultimate lateral bearing capacities and group effects of belled wedge piles are analyzed and discussed. An simplified theoretical calculation method on predicting the lateral bearing capacities of shaped pile groups with considering group pile p-y curves, and longitudinal cross-section variation are proposed. The accuracy and reliability of this developed calculation method are verified through the comparative analysis with model test results obtained in this study and previous literature. The predicted values of lateral bearing capacities have suitable agreement with the measured data. It also shows that the ultimate lateral bearing capacities of belled wedge pile group are nearly 1.8–2.0 times of those of traditional belled pile with the same concrete usage in this study's condition.

Simulation Analysis of Power Frequency Electric Field Around T Connection Tower of Transmission Line

Simulation Analysis of Power Frequency Electric Field Around T Connection Tower of Transmission Line

Machine Learning Approach to Detect Faults in Anchor Rods of Power Transmission Lines

Detecting faults on the anchor rods of power transmission line towers is an essential procedure for guaranteeing the safety, operability, and availability of the electric power system. Such a measure aims to minimize the risk of tower collapse and the associated costs due to the lack of energy, injuries to people, and damage to the reputation of the companies involved. In this letter, we report an alternative noninvasive and nondestructive detection technique through the acquisition of electromagnetic scattering parameters. A novel machine learning (ML) approach is proposed in order to achieve the advantages of such a technique and to deal with the respective drawbacks due to the complexity of signals acquired. A strategy to artificially increase the number of relevant samples in the dataset through the simulations of computational models is performed. Different ML classification algorithms are compared in the task of detecting structural faults in anchor rods in order to define the most suitable to this application. Finally, experimental results show that the methodology proposed achieves a high detection accuracy, surpassing other known methods.

Universal wireless powered terminals for robust overhead transmission line monitoring

A universal and robust wireless power transfer (WPT) system crossing insulators to feed monitoring terminals on power towers of overhead transmission lines is presented in this study. Analyses of the WPT system crossing high-voltage insulators string indicate that system characteristics and energy loss vary under different insulation conditions. Transfer characteristics of the WPT system with different relative positions between the coils and insulators are analysed to find an insensitive scheme. To achieve a non-interacting and relatively efficient operation under the scenarios, magnetic shielding layers are designed to further isolate the WPT system and insulators. Moreover, the resonant frequency point tracking method of this specific WPT system is studied and implemented to achieve robust transfer efficiency. Experimental results prove the feasibility, and the system displays a robust transfer performance with various high-voltage insulators. Such energy feeding system can be used in disc or composite insulation towers universally with simplified installation methods.

Calculation of Lightning Level of Transmission Line Tower Using Graphite Grounding Device

In recent years, graphite grounding devices have developed rapidly and have been widely used in transmission networks. However, the main application is that they are highly corrosive to alkaline soils, and their research on conductivity and lightning resistance is insufficient. Therefore, this paper establishes the ground net model through the simulation software CDEGS, and calculates the power frequency grounding resistance of three different materials of graphite, steel and copper under different conditions and compares them. Using ATP/EMTP software, the calculation model of the lightning strike level including the tower tower, the line, the insulator flashover and the grounding resistance was established. The lightning resistance level of the transmission line tower using the graphite grounding device and the steel grounding device was calculated. Then verify the feasibility of the graphite grounding device.

Cost Effective Design of Extra High Voltage Transmission Lines for Minimizing Transmission Congestion Problems

In Country like India having dense population, laying down new transmission lines is a great challenge. Also country being on fast track development mode, there is unceasing demand of electricity due to ever increasing industrialization. With advent of Extra and Ultra High Voltage transmission lines, corridor width for transmission lines can be reduced significantly. This paper describes utilization of a novel objective function for optimizing the structural design of Extra High Voltage transmission lines. Right of way for transmission lines are decided based on the effects of electromagnetic fields and corona effects in vicinity of the transmission lines. Objective function developed here takes into account the combined effects of electromagnetic fields to optimize design of transmission line tower structure. With compaction of towers further Right of way reduces leading to cost benefits in land procurement. A real time case of a transmission line situated in Gujarat is considered for validating the results of Optimization algorithm developed by authors. MATLAB has been used as programming platform for mathematical modeling as well as a platform for developing GUI that facilitates plotting of fields in vicinity of transmission lines in 2D and 3D environment. Genetic Algorithm coding is used to solve the optimization problem. Significant cost benefits and compactness in transmission tower structure is achievable as is clear from the results shown in this paper. This optimization algorithm can be extended for Ultra High Voltage lines also.

Thor – a New Design of Overhead Transmission Line Towers

ABSTRACTIn these years Denmark puts a significant effort into reducing the CO2‐emission. Consequently, a more flexible and strong electricity transmission grid is needed to be able to transmit the power from the offshore wind farms to the consumers. Furthermore, the grid must be able to reach the international markets.Therefore, a new detailed design of a series of overhead line (OHL) towers have been carried out. The contemporary design has been prepared by the engineers, Ramboll, together with architects, Dissing+Weitling, for the Danish transmission system operator (TSO), Energinet, and the main purpose is to have an aesthetic OHL acceptable to the public together with a cost‐efficient series of towers.The towers are designed as lattice structures. All the traditional lattice OHL towers are constructed using angle bars, while the new design is constructed of circular tubes for all lattice members. This design gives a more open appearance of the tower that is not as massive as the resent designed OHL towers with a shaft of monopoles. The tubes have multiple advantages compared to angle bars: smaller width, lower wind resistance, higher buckling capacity and wider profile opportunities.The traditional angle bar towers are prepared as almost fully bolted structures with no welding. However, even though the members are bolted together welding must be done on lattice towers of circular tubes, and new connections have been developed; also, to meet the aesthetic requirements.This paper introduces the new transmission line design with focus on the tower structure and the special aesthetic designed connections.

Torsional Capacity of Slip Joints with Polygonal Hollow Sections

ABSTRACTPolygonal steel sections are widely used for lighting towers and are more and more adopted for transmission line towers. They convince with an inconspicuous appearance compared to steel lattice towers. Therefore, instead of flange connections “invisible” joints are preferred, such as slip joints. The European design rules for overhead electrical lines (1) cover the use of these joints very generally by a constant ratio of the overlapping length L and the section's diameter D. It is neither distinguished between load conditions nor between cross‐sectional shapes. The ratio value L/D = 1.5 is based on bending tests without regard to torsional moments. In the design of transmission line pylons, torsional loading occurs in the load case of a single‐side loss of a transmission line. Thus, there is a need to improve the knowledge on the load bearing effect of a slip joint connection within this special load case.In this paper the torsional capacity of slip joints is investigated to identify the capability of polygonal cross sections to carry this additional load, particularly in comparison with circular hollow sections. On the basis of numerical and analytical analysis, an adaption for the design of the slip joints is proposed.

Effect of HUD-HUD Wind Intensity on the Structural Behaviour of 220kv Transmission Line Tower at Visakhapatnam

The transmission line towers are one of the important transmission line structures in the distribution of power from the source to the various places. Transmission line towers carry heavy electrical transmission conductors at a sufficient and safe height from ground. In addition to their self-weight they have to withstand all forces of nature like strong wind and earthquake. Therefore transmission line towers should be designed considering both structural and electrical requirements for a safe and economical design. In this paper, an attempt has been made to analyse the behaviour of Transmission line tower under the influence of natural disaster hit Visakhapatnam (District) in Andhra Pradesh (State), India recently in the month of November, 2014. The 220kV tower is modeled and analysed using STADD Pro V-8i and Ansys Mechanical APDL for Maximum loading combinations considering HUD-HUD wind intensity of 275 km/hr (76m/s) and the results obtained are compared with the results obtained for regular wind intensity of 180km/hr(50m/s). Also, the velocity profiles are drawn for both the wind speeds.

Intelligent audio bird repeller for transmission line tower based on bird species variation

Bird-caused damages for overhead transmission lines become one of the main fault types of the power grid, which will affect the safety and reliability of power grid operation and usually bring huge economic losses. The effectiveness of existing bird repeller would deteriorate obviously due to the habituation of birds. Bird bioacoustic vocalization can elicit the avoidance behaviour of conspecific, which can delay the habituation process of birds to bird repeller. An intelligent bird repeller based on bird species variations was proposed. Based on birds’ appearance and vocalization respectively, two light weight networks were designed to identify the approaching bird species; according to the approaching bird species, the corresponding repellent modes were selected; the target was to improve the long-term effectiveness of the bird repeller, which is helpful to reduce the occurrence probability of bird-caused damages.

Modal Behavior Analysis of 220kV Transmission Line Tower using SAP 2000 in Wind Zones I and V

For every developing country, Electrical system plays a crucial role not only in developing the Nation’s economy but also in survival of human beings. The present study deals with a typical 3 Dimensional 220 kV double circuit transmission-line tower is modelled using Sap 2000. The loading conditions considered are normal, earthwire broken and conductor broken conditions. The wind zones I and V are considered since wind zone I has the lowest wind speed 33m/s and for wind zone V having wind speed 50 m /s (Visakhapatnam). All the other parameters like steel sections, height of tower and base width of tower is kept constant for studying the results after the analysis is done. After analysis of tower corresponding wind zones, the results are compared for maximum axial positive and negative deflections, reactions at the supports, different mode shapes and time period, modal mass participation factors, modal participation factors for modal stiffness and frequencies, Eigen value.

Experimental and Finite Element Research of Laterally Loaded Pile

Piles have been widely used for supporting axial and lateral loads for a variety of civil engineering structures such as high rise buildings, transmission lines, bridge piers and port structures. In many cases, lateral loads govern the design of piles. Piles are commonly used to support bridge structures, tall buildings, transmission line towers etc. where poor subsoil conditions are encountered. To suit the various types of structures and their loading conditions, piles of different types, shapes and sizes are being used in practice, the safety of these structures mainly depends on the ability of supporting piles to resist large amount of lateral forces. These lateral forces may be due to the action of wind in case of onshore structures and due to combination of wind and wave action in case of offshore structures. In case of coastal structures, there are additional berthing forces.

Flood Distance Algorithms and Fault Hidden Danger Recognition for Transmission Line Towers Based on SAR Images

Synthetic Aperture Radar (SAR) has been extensively used in the monitoring of natural hazards such as floods and landslides. Predicting whether natural hazards will cause serious harm to important facilities on the ground is an important subject of study. In this study, the distance between the water body and the tower and the flood ratio in the search area and the elevation are defined as the evaluation indicators of the flood hazard of the tower, indicating whether flooding will threaten the safety of the transmission line tower. Herein, transmission tower flood identification algorithms based on the center distance of the tower and the grid distance of the tower are proposed. SAR satellite image data of the flood with a resolution of 10 m are selected to prove the feasibility and effectiveness of the proposed fault identification algorithm. The simulation results show that the SAR satellite image data with a resolution of 10 m can identify the distance accuracy of the transmission tower flood hazard by up to 7 m, which can be used to identify the flood fault of the transmission line tower.

Magnetic-Field-Sensing-Based Approach for Current Reconstruction, Sag Detection, and Inclination Detection for Overhead Transmission System

Noncontact monitoring technique of mechanical and electrical states is increasingly attractive for the overhead transmission system. This paper proposes a new technique to detect the tower inclination and transmission line sag, and measure transmission current simultaneously. The key of this technique is to use the ground magnetoresistive (MR) sensor to measure the magnetic flux density along the center line from the three-phase transmission lines. Moreover, the magnetic field (MF) calculation formulas for a tilted tower are given in this paper. Finally, with MF calculation formulas, an algorithm based on artificial immune system (AIS) is applied to estimate the transmission line sag and tower tilt angles, and reconstruct currents. Model simulations of an overhead transmission system are carried out to verify the idea. The simulation results validate the feasibility of this noncontact approach to estimate mechanical parameters and reconstruct electrical parameters for overhead transmission system.

A Novel on Transmission Line Tower Big Data Analysis Model Using Altered K-means and ADQL

This study sought to propose a big data analysis and prediction model for transmission line tower outliers to assess when something is wrong with transmission line tower big data based on deep reinforcement learning. The model enables choosing automatic cluster K values based on non-labeled sensor big data. It also allows measuring the distance of action between data inside a cluster with the Q-value representing network output in the altered transmission line tower big data clustering algorithm containing transmission line tower outliers and old Deep Q Network. Specifically, this study performed principal component analysis to categorize transmission line tower data and proposed an automatic initial central point approach through standard normal distribution. It also proposed the A-Deep Q-Learning algorithm altered from the deep Q-Learning algorithm to explore policies based on the experiences of clustered data learning. It can be used to perform transmission line tower outlier data learning based on the distance of data within a cluster. The performance evaluation results show that the proposed model recorded an approximately 2.29%~4.19% higher prediction rate and around 0.8% ~ 4.3% higher accuracy rate compared to the old transmission line tower big data analysis model.