High Voltage Transmission Tower Research Articles

Analysis of the Effects of High-Voltage Transmission Line on Human Stress and Attention Through Electroencephalography (EEG)

Knowing the variable-frequency, high-intensity electromagnetic field plays an important role in the humans’ surroundings, numerous studies have been carried out on stress and attention based on EEG data. In this study, a comparison was drawn between the brain waves of individuals living near high-voltage transmission towers and those of people living outside of these zones. The levels of stress and attention were also assessed based on the brain activity of the participants. First, a general questionnaire is completed by the volunteers, and the predisposed samples are included in the research following the screening process. Two 10-member groups (average age of 27 years) of adult males were selected for the research. In one of the groups, the participants are not exposed to high-voltage electric fields. The homes of the members of the second group are located beneath or near high-voltage transmission towers (at a maximum distance of 20 m). Using a 14-channel EEG system, the brain waves of each participant were recorded 5 times over 2 days in the eyes-open resting state while the participants were looking at a white screen. (Ten records of data were obtained per person.) The saliva samples of each participant were also obtained to assess the basal cortisol hormone. The mean EEG stress and attention indices were obtained based on the data on each person, and the mean cortisol level of each group was compared to that of the other group. The investigation and comparison results proved that the mean EEG attention indices of people exposed to high-voltage electric fields were lower than those of the ordinary people. On the other hand, the mean levels of basal EEG stress and salivary cortisol hormone were higher in the people exposed to high-voltage electric fields than the ordinary people. Given the variations of the mean indices of stress and attention in the EEGs and salivary samples of the participants as a result, self-efficacy decreases over time.

Effect of Aluminum Powder additive on Erosion and Bending Resistance of Galvanize Layer

Study of the effect of adding aluminum powder to galvanize melt on the microstructure, thickness of the galvanize layer, behavior and nature of fracture in the total layer through the use of optical microscope and scanning electron microscopy. The addition of the aluminum component (4.5%, 5%, 5.5%) to molten is increase the total thickness of the galvanize layer because it increases the thickness of the interlayer and the adhesive layer with the low carbon steel coupled with the increased dipping time in the molten which also increases the thickness of the total galvanize layer. The cracks that were obtained from the bending test were examined for the samples. The samples with the large thickness and the addition ratio (Al-5.5%) were more resistant to bending. The cracks did not penetrate the surface of the galvanize layer until the angle of bending with the horizon (30º). The erosion resistance was compared to the exposure time of the selection samples, and showed good resistance to erosion at average exposure time. These samples are good in the manufacture of high and medium voltage transmission towers.

Design and Implementation of a New Climbing Robot for High Voltage Transmission Tower

A new type of high voltage transmission tower climbing tower robot is designed. Firstly, the structure of the transmission tower is analyzed to determine that the robot manipulator is a five-degree-of-freedom structure. Secondly, a manipulator capable of automatically positioning and tightening the angle steel surface was designed according to the L-shaped angle steel of the tower. The manipulator adopts electromagnetic absorption and grasping and tightening the angle steel. Thirdly, the theoretical calculation of climbing steps is carried out to determine the maximum step of the torsional climbing gait. Then STM32 SCM is used as a carrier to carry out various functional modules to achieve effective control of the robot’s rotation, movement and positioning. Finally, the finite element simulation of the robot model was performed to analyze the deformation and stress of each component during the climbing process, and the rationality of the structure was verified. In addition, the experiment of tower climbing was carried out with the experiment iron tower in the outdoor. The results show that the robot manipulator is tightened and reliable, the weight bearing is large, the degree of freedom is not redundant, the climbing speed is fast, and the movement of obstacle crossing can be realized smoothly.

Development of an observational checklist for falling risk assessment of high-voltage transmission tower construction workers

Falls from elevation have been reported to cause the highest number of fatalities in the Taiwan construction industry, accounting for 43.53% of all construction worker fatalities for the period from 2006 to 2015, inclusive. High-voltage transmission tower construction is a high-risk operation due to the construction site locations, extreme climatic factors, elevated working surfaces, and narrow working space. However, the factors contributing to the risk of falls in high-voltage transmission tower construction work have not been characterized. This paper describes the development and application of an observational checklist for assessing exposure to fall risks. Three contributing factors, movement, stability, and fall protection measures, were characterized based on the suggestions of ergonomic experts, interviews of supervisors and workers, and on-site observations. Inter-observer reliability test results showed that inter-observer reliability of the observational checklist was acceptable to excellent. A pilot study assessing five primary construction operations suggested that position shifting, wherein workers were found to have frequent exposure to the whole-body movement level and spent the least time in a tied-off full body harness, was the operation with the highest fall risk. These results demonstrated that the observational checklist can be used to identify specific construction operations with fall hazards.

Study on Mechanical Properties of Steel on Transmission Tower under Icing Load

In order to determine the failure mode of high-voltage transmission tower materials under the condition of ice-coating load in an actual line. The Qidian-Luoping 500kV wine glass type transmission tower is selected as the prototype, and the one tower with two lines model of the whole beam unit is established by using the ANSYS finite element software. The loading mode is static load considering icing load and wind load. The most unfavorable wind direction of the transmission tower is obtained by comparing and analyzing the maximum displacement and the stress of the rod under different directions of wind load in the transmission tower. Then the failure mode of transmission tower is studied by the variable ice thickness of the tower line system. The results show that the direction parallel to the cross arm is the most unfavorable direction in the transmission tower. And under the most unfavorable wind direction, with the increase of ice thickness, it is found that the tower head part is more sensitive to icing load than the tower body part. When the thickness of ice coating reaches 30mm, the weak load-bearing rod will appear locally in the transmission tower and the position of the rod is mainly distributed on the outer upper crank arm, the outer side of the ground bracket and the upper side of cross arm of the transmission tower.

A Finite State Machine Based Adaptive Mission Control of Mini Aerial Vehicle

This paper describes a finite state machine for adaptive mission control of mini aerial vehicles. The purpose of a finite state machine is to support mission control during aerial inspection of high voltage transmission lines and insulators independently from environmental and other conditions. One of the basic application of our mini aerial vehicle research is inspection of high voltage transmission lines during its load mode. Around high voltage transmission lines and towers generating a strong electromagnetic field. An electromagnetic fields can be influence negatively to autonomous flight and mission control should be predicted such us situation to avoid possible accident.
 Moreover environmental and weather condition always unpredictable and mission control have to adapt for various type of additional constrains which can be make problem for pre-defined mission map and trajectory.
 Therefore, it needs to develop mission control for autonomous flight with an adaptive option or capability. Such mission control provides less workload and safety guarantee for the inspection team during the process.

Detection of Bird’s Nest in High Power Lines in the Vicinity of Remote Campus Based on Combination Features and Cascade Classifier

High-voltage transmission towers are built to supply electricity for campuses and local residents. In order to guarantee the power supply and safety for remote campus, the unmanned aerial vehicles (UAVs) are used to take the images of high power lines to alarm potential malfunction. A novel method of bird’s nest images detection based on cascade classifier and combination features is proposed. Different features of the bird’s nest and iron tower are analyzed, and the following four novel features are proposed: proportion of white area (PWA), ratio of white pixels (RWP) in each lap, projection feature (PF), and improved burr feature (IBF). The combined features are used to describe the characteristics of the bird’s nest backbone area and the edges, respectively. Furthermore, the cascade classifier combined with the four proposed features is used for the further classification of bird’s nest region. The proposed detection process mainly consists of three stages. First, the suspected bird’s nest region is obtained by template convolution. Second, PWA and RWP with low dimensionality and high discrimination are used to classify the sample set of suspected nest region. Third, based on the previous classification results with positive and negative samples, PF and IBF are adopted to further conduct the secondary classification in order to reduce the misclassified samples, and the final classification label is determined by the second classification results. Experimental results show that the proposed algorithm can accurately detect the nest and achieve good performance.

A Novel Electric Insulation String Structure With High-Voltage Insulation and Wireless Power Transfer Capabilities

High-voltage insulation (HVI) strings are commonly used to hold high-voltage electric cables and electrically isolate them from the grounded transmission tower. In this paper, a novel concept of an electric insulation string with HVI and wireless power transfer (WPT) capabilities is presented. Based on the concept of the domino-resonator WPT system, this new structure consists of coil resonators embedded inside totally sealed insulation discs, which are then connected in series to form the new insulation string structure with the simultaneous HVI and WPT functions. This structure allows energy harvested from the ac magnetic field around the high-voltage cable to be transmitted wirelessly to power an online monitoring system in high-voltage transmission tower continuously, thereby reducing the storage requirements of the battery. The design and analysis of this new WPT structure based on the dimensions of commercially available HVI rod are included. Practical measurements obtained from a hardware prototype of about 25 W have been obtained to confirm the WPT capability of the proposal. An energy efficiency of more than 60% has been achieved for a transmission distance of 1.1 m over a wide range of load.

International Real Estate Review

We present empirical results for the e?ect on residential property values from the construction of high voltage transmission towers on an existing utility right of way. The event window consists of a period of two and a half years during which non-operational 500 kV towers were in place, after which they were taken down. When comparing the proximate transactions within the window to those outside, relative to the same di?erence for distant transactions, we ?nd a negative e?ect on valuation during the presence of the towers, which is most signi?cant for encumbered and abutting properties, and vanishes quickly with distance from the right of way or nearest tower. An event window that corresponds to widespread public knowledge of the pending construction leads to an insigni?cant effect, which suggests that the price formation process is possibly inefficient.

Automatic selection of weights for GIS-based multicriteria decision analysis: site selection of transmission towers as a case study

Transmission line (TL) siting consists of finding suitable land to build transmission towers. This is just one of the numerous complex geographical problems often solved using GIS-based multicriteria decision analysis (MCDA), which is a set of techniques that weight several geographical features to identify suitable locations. This technique is mostly employed using expert knowledge to identify the correct set of weights; thus adding a certain amount of subjectivity to the analysis, meaning that for the same problem if we change the experts involved, we may reach different results.This research is a first attempt to try and solve this issue. We employed a statistical analysis to quantitatively calculate these weights and we tested our method on a case study about transmission line siting in Switzerland. We compared the distances between each sample in our dataset, in this case study these are location of transmission towers, with each geographical feature, e.g. distance from water features. Then we calculate the same distances but for random points, sampled throughout the study area. The reasoning behind this method is that if samples present a distance from a geographic feature statistically different from the random, it means that the feature played an important role in dictating the location of the sample. In this case for instance, high-voltage transmission towers are purposely built as far away as possible from urban areas. Random points are on the contrary by definition sampled without any constraint. Therefore, when comparing the two datasets, we should find that transmission towers have a larger average distance from urban areas than random points. This allows us to determine that this criterion (i.e. distance from urban centers) is important for planning new TL.The results indicate that this method can successfully weight and rank the most important criteria to be considered for an MCDA analysis, in line with weights proposed in the literature. The advantage of the proposed technique is that it completely excludes human factors, thus potentially increasing the social acceptance of the MCDA results.

Effects of elevation change on mental stress in high-voltage transmission tower construction workers

High-voltage transmission tower construction is a high-risk operation due to the construction site locations, extreme climatic factors, elevated working surfaces, and narrow working space. To comprehensively enhance our understanding of the psychophysiological phenomena of workers in extremely high tower constructions, we carried out a series of field experiments to test and compare three working surface heights in terms of frequency-domain heart rate variability (HRV) measurements. Twelve experienced male workers participated in this experiment. The dependent variables, namely, heart rate (HR), normalized low-frequency power (nLF), normalized high-frequency power (nHF), and LF-to-HF power ratio (LF/HF), were measured with the Polar RS800CX heart rate monitor. The experimental results indicated that the task workload was similar between working surface heights. Tower construction workers perceived an increased level of mental stress as working surface height increased.

Seismic performance evaluation of high voltage transmission towers in South Korea

The electric power transmission network is a crucial lifeline in modern society, and it needs to be protected against extreme loading conditions such as in an earthquake. The seismic fragility curves of high voltage transmission towers in South Korea are developed based on the limit states that are defined in terms of yielding and buckling of the structural members of the towers. The finite element models of the representative transmission towers in South Korea are developed based on the assumption of linear elastic behavior, and a series of time history analyses are performed using a set of 20 recorded ground motions. The maximum likelihood estimation method is used to develop fragility curves from numerous simulations. It is concluded that the transmission towers are safe under a design level earthquake in South Korea. When a strong earthquake occurs, buckling of the members is more likely to occur before yielding in the axial direction in the case of the 765 kV and 345 kV transmission towers, while the opposite is observed for the 154 kV transmission tower.

Electric field energy harvesting for on‐line condition‐monitoring device installed on high‐voltage transmission tower

A method for powering an on-line condition-monitoring device installed on a high-voltage transmission tower is presented. The technique uses the harvesting plate and a transformer both installed away from the transmission line to harvest the electric field energy. The circuit model of the method is analysed and the power equation given. The method has been experimentally validated. When the stray capacitance is 40 pF, about 645 mW was obtained with the load resistance 0.9 kΩ once 50 kV AC was applied on the electric field generator.

송변전 지리정보 시스템을 이용한 고압 송전선과 거주지 간 이격거리에 대한 인식 평가

이번 연구에서는 송변전 지리정보 시스템(Transmission and substation Geographic Information System: TGIS)을 이용하여 일반인들이 판단한 고압 송전탑 및 송전선, 변전소와 거주지 간 거리 인식이 실측 거리와 일치하는지 확인해 보았다. 총 725명의 응답자 중 136명이 고압 송전탑 및 송전선, 변전소가 눈에 보이는 거리에 있다고 응답하였고, 이 중 114명이 TGIS로 분석할 수 있는 유효한 주소를 제공하였다. 114명 중 42명(36.8 %)은 실측 거리보다 인식 거리가 짧았으며, 15명(13.2 %)은 인식 거리보다 실측 거리가 짧았다. 일반인들의 고압 송전탑 및 송전선, 변전소와 거주지 간 거리 예측의 타당도가 높지 않은 점을 바탕으로 했을 때, 이를 극저주파 전자기장 노출량의 대용물로 사용하는 것은 부적절할 것으로 보인다. The purpose of this study was to evaluate the perceived distance from home to high-voltage power lines using a transmission and substation geographic information system(TGIS). Of the 725, 136 respondents reported that high voltage power transmission tower, power lines or substation was within visual field range from home. Among them, 114 respondents reported valid address, which could be used in the analysis of TGIS. Forty two respondents(36.8 %) estimated that the power lines were closer and 15 respondents(13.2 %) estimated that they were farther than they actually were. Our current findings suggest that the reported distance from home to high-voltage power transmission towers, power lines, and substations cannot be used as a proxy for exposure to electromagnetic fields due to the low validity.

Preparation and Property of the Steel Fiber Concrete Modified by Acrylic Acid Emulsion

Grounding net is necessary to ensure the security of electrical equipment and personal safety for the high voltage transmission tower. The grounding resistance under power frequency of the grounding net must meet the national standard. The normal resistance-reducing agents show conductivity instability, short service life and poor water-retaining property. The conductive concrete is capable of good permeability, water-retaining property and conductivity. While there is an contradiction between the high mechanical strength and good conductivity. In this paper, the acrylic acid emulsion is used to increase the adhesion stress between the steel fibers and the concrete.

Research on Fiber Bragg Grating Sensor Technology

This paper presents a method for the detection of transmission tower. It is a common phenomenon that high voltage and strong magnetic field exist in the environment of high voltage transmission tower. Compared with electronic sensor system, fiber Bragg grating sensing technology could resist harsh environment effectively. As a kind of passive devices, fiber Bragg grating tilt sensor can monitor the tilted state of high voltage tower easily. With the help of on-line monitoring system, we can effectively raise maintenance strategy for high voltage tower and analyze the variation trend of the tower. The system is convenient to repair and maintain the high voltage tower at the same time.

Buckling Analysis of Large-Scale Transmission Tower Structure

The high-voltage transmission tower transmission lines is a major component and typically a high steel tower, is a tall, flexible structures. In this paper, the finite element method to establish a large-scale three-dimensional model of the transmission tower space, computational analysis of the transmission tower structure first six buckling modes and critical load, examined the order buckling mode characteristics. Research on the structural stability of large power transmission tower design has some theoretical significance and application value.

Wind-rain-induced vibration test and analytical method of high-voltage transmission tower

A new computational approach for the rain load on the transmission tower is presented to obtain the responses of system subjected to the wind and rain combined excitations. First of all, according to the similarity theory, the aeroelastic modeling of high-voltage transmission tower is introduced and two kinds of typical aeroelastic models of transmission towers are manufactured for the wind tunnel tests, which are the antelope horn tower and pole tower. And then, a formula for the pressure time history of rain loads on the tower structure is put forward. The dynamic response analyses and experiments for the two kinds of models are carried out under the wind-induced and wind-rain-induced actions with the uniform and turbulent flow. It has been shown that the results of wind-rain-induced responses are bigger than those of only wind-induced responses and the rain load influence on the transmission tower can't be neglected during the strong rainstorm. The results calculated by the proposed method have a good agreement with those by the wind tunnel test. In addition, the wind-rain-induced responses along and across the wind direction are in the same order of response magnitude of towers.

Finite Element Model of High-Voltage Transmission Tower Confirmed

Model selection is carried out structural analysis Transmission Tower one of the priorities. Through the establishment of traditional beams - truss hybrid model, improved beam - beam hybrid model and frame model, a modeling analysis of angle steel tower cathead. First on the transmission tower modal analysis, and then the common wind conditions and ice conditions of the maximum stress and maximum displacement results are discussed, and then local analysis. Identify similarities and differences between the three models, discusses the advantages and disadvantages of the model to meet the design requirements of the situation and the results can be obtained more reasonable feasibility.

Design Optimization of Composite-Insulated Telescopic Aerial Boom

Telescopic aerial boom system is used transport the object or can be used to ease working high altitude. Installation of high voltage transmission tower due to urbanization is increasing. Because working on high places such as wiring operations and electrical maintenance has increased the demand.Boom of aerial work platform are made of steel. So, necessity for safe isolation aerial work platform used for electrical work is increasing. This paper is proposed about applied to the material used in the aerial work platform boom. Insulating material was applied to the aerial work platform the last end boom in boom system. In this paper the structural analysis and formulation of the methodology for the design optimization of telescopic aerial lift boom system is presented. The main objective of the design optimization is to obtain lightweight boom system by optimizing boom cross-section shape, overlap length and plate thicknesses in the worst condition possible. The design optimization problem is formulated as minimizing the weight of the boom system. In this paper analyzes the design of the telescopic aerial boom system of applying the insulating material using the Ansys.