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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Critical span analysis of overhead lines

Jerrell, Jeffrey W. 05 1900 (has links)
No description available.
2

Experimental verification and modification of a real-time ampacity program for overhead conductors

Savoullis, Yiannakis C. 05 1900 (has links)
No description available.
3

Transient thermal model of overhead electric lines

Byrd, William Randall 08 1900 (has links)
No description available.
4

An investigation into high impedance ground faults on SWER systems / by Enyonam Agbodo.

Agbodo, Enyonam Unknown Date (has links)
Thesis (MEng)--University of South Australia, 1995
5

An investigation into high impedance ground faults on SWER systems / by Enyonam Agbodo.

Agbodo, Enyonam Unknown Date (has links)
Thesis (MEng)--University of South Australia, 1995
6

Assessment of devices designed to lower the incidence of avian power line strikes /

Crowder, Michael R., January 2000 (has links) (PDF)
Thesis (M.S.)--Purdue University, 2000. / Vita. Includes bibliographical references. Also available electronically on the Internet.
7

Transient temperature distributions in short-circuited electrical conductors

McWhorter, Bruce Burnett 08 1900 (has links)
No description available.
8

Calibration of UV-sensitive camera for corona detection /

Du Toit, Nicolaas Serdyn. January 2007 (has links)
Thesis (MScIng)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.
9

Mechanical oscillations on overhead transmission lines

Du Plessis, Pieter 08 May 2014 (has links)
D.Ing. (Mechanical Engineering) / This research proposed to develop a mathematical model for the prediction of aeolian vibration levels on overhead transmission lines in order to be able to ensure that damping systems are designed optimally in future. In order to enhance the understanding of aeolian and wake-induced vibration further, it also proposed to implement and apply the fluid flow simulation technique of Computational Fluid Dynamics (CFD) to both single conductors and conductor bundles. The Introduction of the CFD tool to the field of transmission line vibration, will ensure that bundles could be optimally designed for future applications. Wind-induced vibrations are known to cause expensive damage to the conductors and related hardware through fatigue or clashing of the bundled conductors. The primary cause of conductor aeolian vibration is the alternate shedding of wind-induced eddies from the top and bottom sides of the conductor, whereas wake-induced oscillations is peculiar to bundled conductors and arises from effects of the shielding of leeward conductors in bundles by windward ones. In order to study the phenomenon of aeolian vibration, research was undertaken utilising a full scale transmission line test station close to Kroonstad in the Orange Free State. Commercially available computer based packages were used for the development and simulation of both the mathematical model and fluid flow. During the flow simulations, an actual Zebra conductor and Zebra bundle configuration were utilised. For the development of the mathematical model, the pratical results, as measured at the Kroonstad transmission line test station during Phase I, were utilised. From the tests performed during Phase I, it was concluded that the damping solutions, currently used by Eskom as tested during Phase I, are all effective in controlling the aeolian vibration. The Stockbridge damper proved to be avery effective damper. Two models for the prediction of aeolian vibration levels were derived. Results showed that the vibration levels could be estimated to the correct order of magnitude and in many cases the precise values. The accuracy of the model was further improved by the inclusion of the Strouhal number as a function of windspeed. It has been decided by the author 10 develop and design a low cost vibration activity indicator for aeolian vibration measurements. The T-R-I-V-A-I has shown that it is a repeatable, reliable device, Ideally suited for line vibration detection. A new device, the W-I-V-I, has also been designed and implemented by the author for the detection and quantification of wake-induced vibration. During the simulation of the flows around a conductor in the steady state, it was established that the flow around as smooth cylinder and a Zebra conductor, is very similar, however, it was established that the rough outer surface of the Zebra conductor acts as a vortex generator. It has been found that a stability relationship exists between the degree of symmetry of the pressure cell, directly in front of the leeward conductor and the wake-induced vibration. Results for the unsteady flow situation showed the initiation and dispersion of the vortices as they are generated alongside the conductor. It is recommended that the developed model's accuracy be further enhanced. It should be established if .there are families of curves and data that belong together and that contribute to the amount of scatter in the parameters measured such as vibration amplitude, Strouhal number, etc. The applicability of CFD to the transmission line field should be enhanced, with the view of increasing bundle performance, both from an electrical and mechanical point of view.
10

An Aerodynamic Investigation of the Causes of Overhead Electrical Transmission Line Gallop

Skousen, Eric Nathan 01 April 1973 (has links)
Overhead electrical transmission lines vibrate due to the action of a prevailing wind. These cable vibrations can be classified into two categories— high-frequency and low-frequency. The high-frequency vibrations, "aeolian" vibrations or "singing wires," is a low-amplitude phenomenon. It has been largely controlled with the use of various mechanical dampers [l, 2],

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