Search for dissertations about: "surface charge"

Showing result 1 - 5 of 478 swedish dissertations containing the words surface charge.

  1. 1. Electrical Charges on Polymeric Insulator Surfaces and their Impact on Flashover Performance

    Author : Sarath Kumara; [2012]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; streamer criterion; polymeric insulation; flashover voltage; surface potential; bulk conductivity; surface conduction; humidity; bulk neutralization; charge decay; Surface charge; silicone rubber; corona charging; gas neutralization;

    Abstract : Utilization of remotely located sustainable energy resources such as solar, wind and hydro calls for further developments of long-distance electric power transmissions operating at ultra-high voltage (UHV) levels which may exceed 1000 kV ac and 800 kV dc utilized today. It is foreseen that insulation of such transmission systems is to be based on polymeric materials that can provide a number of technical benefits over traditionally used glass and porcelain based insulation. READ MORE

  2. 2. Surface Charge Dynamics on Polymeric Insulating Materials for High Voltage Applications

    Author : Shahid Alam; [2014]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC insulation.; gas neutralization; decay rate; Surface charging; electrical conductivity; surface potential; charge transport; ambient pressure;

    Abstract : To meet increasing demands in electric energy, it is essential to enhance production of electricity from renewable energy sources (solar, wind and hydro). Such generation sites, however, are usually separated from consumption sites by long distances. READ MORE

  3. 3. Adsorption of surface active elements on the iron (100) surface A study based on ab initio calculations

    University dissertation from Stockholm : KTH

    Author : Weimin Cao; KTH.; [2009]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sulfur; oxygen; surface adsorption; iron surface; ab initio calculations; adsorption energy; work function; difference charge density; thermodynamic stability; average velocity; TECHNOLOGY Materials science; TEKNIKVETENSKAP Teknisk materialvetenskap;

    Abstract : In the present work, the structural, electronic properties, thermodynamic stability and adatom surface movements of oxygen and sulfur adsorption on the Fe surface were studied based on the ab initio method.Firstly, the oxygen adsorbed on the iron (100) surface is investigated at the three adsorption sites top, bridge and hollow sites, respectively. READ MORE

  4. 4. Charge transport in polymer-based insulating materials for high voltage applications: effect of single- and multi-layered structures

    University dissertation from Gothenburg : Chalmers tekniska högskola

    Author : Tuan Anh Hoang; [2016]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; charge trapping and de-trapping; polyethylene; surface potential decay; enamel insulation; charge transport; charging current; charge injection; charge mobility; DC conductivity; nanocomposite;

    Abstract : Polymer composites have been widely employed as electrical insulating materials for high voltage components and devices such as power cables, gas-insulated systems, rotating machines, line and post insulators, etc. Such materials are usually made by introducing inorganic oxides (SiO2, TiO2, Al2O3, MgO) into polymeric matrices e.g. READ MORE

  5. 5. Simulations of Simple Fluids and Surface Forces

    University dissertation from Department of Chemistry, Lund University

    Author : Martin Trulsson; Lund University.; Lunds universitet.; [2011]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Molecular modeling; Surface Forces; Dielectric Constant; Charge Capacitance; Charge Regulation; Hypersphere; Statistical mechanics; Intermolecular interactions; Col- loidal Stability; Simulations; Fluids;

    Abstract : A considerable part of all chemistry in nature and in industry occurs in solvents. Sol- vents affect both the interactions and the reactions of the particles immersed in them. The work in this thesis concerns the properties of ionic and polar solvents, as well as the interactions between solutes and/or dispersed particles. READ MORE