Dynamic Analysis Of Transmission Line Towers

International Journal for Research in Applied Science and Engineering Technology, 2021

The electrical 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, earthquake and snow load. Therefore transmission line towers should be designed considering both structural and electrical requirements for a safe and economical design. Modeling of transmission tower by using finite element method. the horizontal displacement (X-direction) is found to be maximum for the model-10 as compared to the other models. As the height goes on increasing the displacement found to be increasing. Also as the wind speed is increasing the displacement is also found to be increasing.

This paper presented an overview on the dynamic analysis and control of the transmission tower-line system in the past forty years. The challenges and future developing trends in the dynamic analysis and mitigation of the transmission tower-line system under dynamic excitations are also put forward. It also reviews the analytical models and approaches of the transmission tower, transmission lines, and transmission tower-line systems, respectively, which contain the theoretical model, finite element (FE) model and the equivalent model; shows the advances in wind responses of the transmission tower-line system, which contains the dynamic effects under common wind loading, tornado, downburst, and typhoon; and discusses the dynamic responses under earthquake and ice loads, respectively. The vibration control of the transmission tower-line system is also reviewed, which includes the magnetorheological dampers, friction dampers, tuned mass dampers, and pounding tuned mass dampers.

In India large population is living all over the country and electricity supply demand need for this population makes recruitment of a large transmission and distribution system. Formulation of Transmission tower is proffered in assessment of confronting high voltage transmitting conductors and insulators to stance in need of altitude from ground level. Transmission Line Towers comprise of about 28 to 45 percent of the absolute cost of the Transmission Lines. The purpose of a transmission line tower is to support conductors booming electrical power and one or two ground wires at appropriate distances above the ground level and from each other. The observations from both structural and electrical fields are analysis in designing transmission line towers. There are various factors which influence the stability and performance of transmission tower are viewed in this paper. This Paper discussed and review the Methodology adopted for Analysis and Design of transmission towers. This paper can also be used for study of different parameters used in Analyzing and Designing of transmission towers.

Engineering Sciences, 2011

International Journal of Engineering & Technology

A power transmission tower carries electrical transmission conductor at adequate distance from the ground. It must withstand all nature’s forces besides its self-weight. In structural analysis, natural frequency, mode shape and damping ratio are used to define the structural dynamic properties which relate to the basic structural features. This paper described the dynamic analysis including the modal and the time history analysis on each segment of the self-supported transmission tower to understand its dynamic responses subjected to wind action. The factors such as different height above ground, a different value of wind speed and different wind angle of attack were included in this study to see the influence of those factors towards dynamic response of the structure. The contribution of the wind towards the displacement of the structure is determined in this study by comparing the result obtained in a linear static analysis which considered the load combination without and with th...

ISRN Power Engineering, 2013

This paper proposes an approach to the study of the transient response and the frequency characteristics of power lines' towers, when subjected to lightening strikes. It starts with dividing the nonuniform line representing the tower into a number of sections. From the usually known dependence of the tower's characteristic impedance on the vertical coordinate and the application of a recursive circuit reduction technique, an s-domain expression for the tower input impedance can be obtained. This expression, followed by the numerical Laplace inversion, is utilized for the determination of the tower's transient response. The impedance expression can be also used to determine the tower's resonance frequencies. This was used to demonstrate some potentially critical situations in which the tower is hit by lightning strikes comprising multiple current pulses. The validity of the proposed technique is demonstrated by comparing the achieved results with those already available in the literature for the same case studies.

In the contemporary era, the telecommunication industry plays a great role in human societies and thus much more attention is now being paid to telecommunication towers than it was in the past. So the analysis and design of telecommunication tower for wind and earthquake are the major issues which are playing significant role in recent decades in the designing. Telecommunication towers with different configurations behave differently for lateral loadings. Lot of literature is available which proposes different formulas to determine seismic parameters. Also previously, designers considered safety of towers only against overturning. During the seismic event some members of towers reach its ultimate strength causing failure. However, performance of the different configurations of telecommunication tower against earthquake is not much discussed in the literatures. So there is need of in-depth study of behaviour of telecommunication tower for different configurations and its analysis for earthquake effect. In this research the wind and seismic analysis of telecommunication towers is carried out. Telecommunication towers with square in plan, with different bracing systems are designed and checked for gravity loading. The same models are modelled using STAAD Pro. The towers are analyzed by non-linear dynamic method. The results obtained from non-linear dynamic analysis are compared on the basis of various parameters.

2016

Steel lattice transmission line towers (TL) are widely used as supporting structures for overhead powerlines. According to their supporting configuration, these free-standing tower structures are classified as: Self-supporting towers and guyed towers. In general, they are designed for conductors’ weight and environmental loads such as ice accretion and wind gustiness. Other exceptional loads, such as cable rupture and ice-shedding effects, are also considered. Due to an overall perception that these structures have a relatively low vulnerability to earthquake loads, the earthquakes effects are usually not considered in TL tower design. The current standards, for instance, do not require a design check for earthquake loads, although a significant percentage of transmission line infrastructure is located on Western and Eastern Canada where the seismic risk is considered high and moderate-to-high. The main objectives of this research are: i) to assess the sensitivity of typical TL towe...

Over the past 30 years, the growing demand for wireless and broadcast communication has spurred a dramatic increase in communication tower construction and maintenance. Failure of such structures is a major concern. In this paper a comparative analysis is being carried out for different heights of towers using different bracing patterns for Wind zones I to VI and Earthquake zones II to V of India. Gust factor method is used for wind load analysis, modal analysis and response spectrum analysis are used for earthquake loading. The results of displacement at the top of the towers and stresses in the bottom leg of the towers are compared.

There has been an expanding pattern of development of microwave correspondence and transmission line towers everywhere throughout the nation. The establishments of such towers constitute almost 20 to 40 percent of the aggregate cost of towers. Notwithstanding, exceptionally little data is accessible on the plan system of tower establishment. The paper shows the similar investigation of transmission tower establishments, there are different forces is subjected to transmission towers foundation which is effect on the stability of transmission tower. Generally shallow foundation and deep foundation (pile) is used but only deep foundation use for extreme condition. So if the soft soil then to improve the stability connected foundation system is use.