scholarly journals Note on surges of voltage and current in transmission lines

1936 ◽  
Vol 156 (887) ◽  
pp. 1-5 ◽  
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Subject Matter ◽  
Unit Length ◽  
The Self ◽  
Practical Calculation ◽  
Electrical Transmission ◽  
Present Treatment ◽  
Distant Point ◽  
The Subject

The increase in extent and capacity of electrical transmission systems lends increasing importance to the subject matter of this note; for excessive survoltage, particularly when it occurs suddenly, is apt to damage equipment and endanger life, cause a large and virtually instantaneous rise of potential at the point struck; and it is important, in the study of its effects, to determine the resulting disturbance at a distant point of the line. A solution of the fundamental case of an infinite transmission line, at the end of which a change of potential suddenly occurs, was propounded by Heaviside, but this solution appears to be incorrect. It nevertheless seems to have been very generally accepted by engineers who have dealt with the problem. The subject has also been discussed by Jeffreys, but it is felt that the present treatment offers advantages, not only in that it leads to a clearer physical apprehension of the phenomena, but also as being more amenable to the purpose of practical calculation. The equations between voltage V and current i at any point x and time t are d V/ dx + L di / dt + R i = 0, (1) di / dx + K d V/ dt + SV = 0, (2) where R is the resistance, S the leakage conductance, L the self-induction, and K the capacity of the line-all reckoned per unit length. Whence, d 2 V/ dx 2 = LK d 2 V/ dt 2 + (RK + SL) d V/ dt +RSV. (3)

scholarly journals Magnetic Field of 1200kv Transmission Line by FEM & MATLAB

2019 ◽  
Vol 9 (1) ◽  
pp. 1105-1110
Keyword(s):  
Magnetic Field ◽  
Transmission Line ◽  
Transmission Lines ◽  
Biological Effects ◽  
Field Analysis ◽  
Field Calculation ◽  
Voltage Level ◽  
Line Voltage ◽  
The Subject ◽  
Electric Field Analysis

With rapid industrial and commercial growth and flourishing population, power demand is increasing rapidly. Modern methods of UHV transmission lines are important to transmit bulk amount of power more efficiently in comparison to earlier methods of transmission. 1200 KV UHV transmission line is India future and therefore forthcoming project to tackle this situation. However as line to line voltage level increases, complexity of the transmission line increases. But, with higher level of line to line voltage, complexity of transmission line increases. ROW is one of the major concerns with transmission lines. Many parameters need to take care in designing; one of them is a magnetic field distribution at surroundings of transmission line. India has initiated to expand its UHV range to 1200kv. Paper suggest magnetic field of three configurations of the 1200KV line. Horizontal and vertical configuration test lines have been installed. Analysis has been done by two methods finite element method and (Method of images) analytical method. FEM is used to solve partial differential equations. Results from both methods have been compared. 3D electric field analysis of configuration also performed. Plotted results are compared with ICNIRP standards and safety limits defined. Adverse effects of excess magnetic field is also discussed. Biological effects of electromagnetic field on people, animals and plants are also discussed. Thus paper aimed at magnetic field calculation and verification with respect to standard. It also helps to utilize less right of way. The subject is under broad development due to its advantages over lower voltage levels and holds significance in future as well.

scholarly journals Solving the Complexity Problem in the Electronics Production Process by Reducing the Sensitivity of Transmission Line Characteristics to Their Parameter Variations

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Talgat R. Gazizov ◽  
Indira Ye. Sagiyeva ◽  
Sergey P. Kuksenko
Keyword(s):  
Transmission Line ◽  
Production Process ◽  
Transmission Lines ◽  
Unit Length ◽  
Characteristic Impedance ◽  
Optimal Choice ◽  
Wide Range ◽  
Complexity Problem ◽  
Parameter Variations ◽  
Parameter Values

In this paper we consider the complexity problem in electronics production process. Particularly, we investigate the ways to reduce sensitivity of transmission line characteristics to their parameter variations. The reduction is shown for the per-unit-length delay and characteristic impedance of several modifications of microstrip transmission lines. It can be obtained by means of making an optimal choice of parameter values, enabling proper electric field redistribution in the air and the substrate. To achieve this aim we used an effective simulation technique and software tools. Taken together, for the first time, they have allowed formulating general approach which is relevant to solve a wide range of similar tasks.

scholarly journals Experiencing Transformative Learning: An Autoethnographic Journey through Ethical Dilemma Story Pedagogy (EDSP)

2019 ◽  
Vol 7 ◽  
pp. 227-244
Author(s):  
Kashiraj Pandey
Keyword(s):  
Cultural Heritage ◽  
Transformative Learning ◽  
Subject Matter ◽  
Ethical Dilemma ◽  
Lived Experiences ◽  
The Self ◽  
Research Participants ◽  
The Subject

I believe our cultural heritage has so much potential for creating new forms of knowing about the self, others, community, and environment while also revealing the interconnected spaces and realities that reside between cultures and people. The Nepalese heritage encompasses through a rich tradition of narratives in storying. For the purpose of present research, I composed two ethical dilemma stories and discussed them in classrooms with a critically reflective understanding of the subject matter where I utilised the local, lived contexts and characters from the Nepalese society. The results have shown that this study, with the use of ethical dilemma stories as a key tool to interact with the research participants, gave sufficient challenges and possibilities for transformative learning. Therefore, the aim of this paper is to explore the unification of my personal, professional, and cultural spheres that are focused on the importance of transformative learning using an autoethnographic methodology. The paper also tries to document my lived experiences through stories as the understanding of my own self, other selves, and cultures around me.

scholarly journals On Heaviside's contributions to transmission line theory: waves, diffusion and energy flux

2018 ◽  
Vol 376 (2134) ◽  
pp. 20170457
Author(s):  
Christopher Donaghy-Spargo
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Physical Nature ◽  
Electromagnetic Theory ◽  
Electrical Transmission ◽  
Important Work ◽  
Transmission Line Theory ◽  
Energy Current ◽  
Electrical Transmission Line ◽  
Line Theory

This paper surveys some selected contributions of Oliver Heaviside FRS (1850–1925) to classical electromagnetic theory and electrical engineering science. In particular, the paper focuses on his contributions to the development of electrical transmission line theory and his deep insights into the ‘physical’ nature of the phenomena relating to nineteenth century telegraphic problems. Following a brief historical introduction to the life of Heaviside to put his achievements in context, we explore his contributions to the reformulation of Maxwell's equations and the understanding of electromagnetic wave propagation along the external region of transmission lines. This leads naturally to his researches regarding the electromagnetic diffusion process inside the line conductors and his subsequent realization that the circuital parameters, usually assumed constant, are not always so. Finally, taking both these internal and external viewpoints of the conductors, his important work regarding the flow of energy described by his ‘energy current’ concept is presented. This article is part of the theme issue ‘Celebrating 125 years of Oliver Heaviside's ‘Electromagnetic Theory’’.

scholarly journals Analogue Hawking Radiation in Nonlinear LC Transmission Lines

Universe ◽  
2021 ◽  
Vol 7 (9) ◽  
pp. 334
Author(s):  
Haruna Katayama ◽  
Noriyuki Hatakenaka ◽  
Ken-ichi Matsuda
Keyword(s):  
Black Holes ◽  
Electromagnetic Wave ◽  
Transmission Line ◽  
Transmission Lines ◽  
Hawking Radiation ◽  
Reductive Perturbation Method ◽  
Electrical Transmission ◽  
Third Order ◽  
Nonlinear Transmission Lines ◽  
Electrical Transmission Line

Analogue systems are used to test Hawking radiation, which is hard to observe in actual black holes. One such system is the electrical transmission line, but it suffers the inevitable issue of excess heat that collapses the successfully generated analogue black holes. Soliton provides a possible solution to this problem due to its stable propagation without unnecessary energy dissipation in nonlinear transmission lines. In this work, we propose analogue Hawking radiation in a nonlinear LC transmission line including nonlinear capacitors with a third-order nonlinearity in voltage. We show that this line supports voltage soliton that obeys the nonlinear Schrödinger equation by using the discrete reductive perturbation method. The voltage soliton spatially modifies the velocity of the electromagnetic wave through the Kerr effect, resulting in an event horizon where the velocity of the electromagnetic wave is equal to the soliton velocity. Therefore, Hawking radiation bears soliton characteristics, which significantly contribute to distinguishing it from other radiation.

scholarly journals O is for Orientalism: the dynamics of the sexual tourist gaze in Laurent Cantet’s Vers le sud/Heading South (2005)

2021 ◽  
Vol 46 (1) ◽  
pp. 27-47
Author(s):  
Charlotte Hammond ◽  
Andrew McGregor
Keyword(s):  
Subject Matter ◽  
Historical Context ◽  
The Self ◽  
The Political ◽  
Economic Power ◽  
Political Repression ◽  
Spatial Politics ◽  
Tourist Gaze ◽  
The Subject ◽  
Sexual Tourism

This article explores the Orientalist dynamics of North/South sexual tourism in Laurent Cantet’s Vers le sud/Heading South (2005). The narrative of the film is structured around the self-interested motivations of three white middle-aged bourgeois Western women who travel from North America to Haiti in the late 1970s in order to explore their sexuality in what they perceive as an island paradise, effectively exiling themselves from the codified social behavior expected of them in their homeland. The women avail themselves of the pleasures offered by young black Haitian men, often in exchange for money or goods, and fuel one-sided fantasies of romantic love with their local hosts, seemingly oblivious to the Orientalist nature of such an imbalance of social and economic power. The article explores the historical context of the political repression and violence of late-1970s Haiti under the Duvalier regime, as well as the manifestations of spatial politics represented in the film. In its Haitian setting, Vers le sud sheds light on a relatively unfamiliar cultural and social milieu for the Western/Northern audience, with the director keenly aware of the exoticism of the subject matter and the impossibility of the film to maintain its neutrality in a problematic engagement with the Orient/South. The article argues that the privileged position of the film’s protagonists is matched not only by Cantet’s directorial gaze, but also by the intellectual detachment of postcolonial scholars such as the article’s authors, who acknowledge that their engagement with the subject matter risks re-enacting the Orientalist dynamics they seek to expose.

scholarly journals In-Cloud Icing in the Columbia Basin

2009 ◽  
Vol 137 (12) ◽  
pp. 4369-4381 ◽  
Author(s):  
Ronald M. Thorkildson ◽  
Kathleen F. Jones ◽  
Maggie K. Emery
Keyword(s):  
Transmission Line ◽  
Water Content ◽  
Transmission Lines ◽  
Liquid Water ◽  
Liquid Water Content ◽  
Weather Data ◽  
Cloud Base ◽  
Columbia Basin ◽  
Electrical Transmission ◽  
Dewpoint Temperature

Abstract On 24 November 2005, 11 lattice steel towers of a high-voltage electrical transmission line running along the edge of an escarpment were damaged by an accumulation of rime on overhead ground wires. Cold air pooling in the Columbia basin of eastern Washington several days before the failure led to the formation of low-level fog and low clouds with temperatures below freezing at the elevation of the transmission line. The liquid water content profile of the cloud formed by air rising over Badger Mountain north of Wenatchee, Washington, is estimated using the air temperature, dewpoint temperature, and air pressure as measured at Wenatchee in the Columbia River valley below the line. Cloud median volume droplet diameters are estimated using typical droplet concentrations. The validity of the computed liquid water content is determined by comparing the measured cloud-base heights at Wenatchee with the calculated cloud-base heights. The mass and density of ice accreted on the ground wires and conductors of the transmission line are modeled using assumed wind speeds at the top of the escarpment with the estimated cloud properties. Results are compared with the density and mass of an ice sample retrieved from the field. This event is compared with other modeled in-cloud icing events from 1973 to 2007 using the period of record of Wenatchee weather data. This paper illustrates an approach for estimating the severity of in-cloud icing on the wires of transmission lines subject to cloud liquid water contents that have been enhanced by the local terrain.

scholarly journals Descending and ascending trajectories of dialogical analysis: seventh analytic interpretation on the short story "The guerrillero"

2016 ◽  
Vol 27 (2) ◽  
pp. 189-200 ◽  
Author(s):  
Danilo Silva Guimarães
Keyword(s):  
Short Story ◽  
Subject Matter ◽  
Empirical Data ◽  
The Self ◽  
Methodological Issues ◽  
Concrete Situation ◽  
Starting Point ◽  
The Subject ◽  
Albalucia Angel

Abstract: The dialogical unity for the analysis of the Self includes the descending intersubjective interpenetration of the psychologist's lens into the self-others' feeling/thinking together with the analytic demonstration concerning the transformations of the objects that participate in the intrapsychological stream of the focused feeling/thinking. The theoretical and methodological issues selected for our present study concern how to make dialogical analysis out of empirical data and how to articulate the analyzed content to the interpretative whole situation from which the researcher and the subject matter are part of. Dialogism does not have a standardized procedure and we are not considering that there is only one correct methodological procedure in dialogical psychology. Nevertheless, discussing some dialogical approaches to a short story from Albalucía Ángel (1979), we found that the starting point for the dialogical analysis should be the mediated relation of the Self with the others, emphasizing the relevance of the extra-verbal concrete situation.

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