Sökning: "flashover voltage"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden flashover voltage.

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

    Författare :Sarath Kumara; Chalmers tekniska högskola; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  3. 2. Prevention of Biofilm Formation on Silicone Rubber Materials for Outdoor High Voltage Insulators

    Författare :Sevil Atari Jabarzadeh; Sigbritt Karlsson; Ferruccio Doghieri; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High voltage insulator; silicone rubber; biofouling; biofilm; biocide; superhydrophobicity; self-cleaning; hierarchical roughness;

    Sammanfattning : Microbial colonization on the surface of silicone rubber high voltage outdoor insulators often results in the formation of highly hydrated biofilm that influence the surface properties, such as surface hydrophobicity. The loss of hydrophobicity might lead to dry band formation, and, in the worst cases, flashover and failure of the insulator. LÄS MER

  4. 3. Electrical Charges on Polymeric Insulator Surfaces and their Impact on Withstand Performance

    Författare :Sarath Kumara; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; impulse corona; Surface charge; impulse flashover voltage; corona charging; streamer criterion; surface potential decay; charge relaxation;

    Sammanfattning : Use of polymeric materials for high voltage outdoor insulation systems is increasing continuously. Insulating polymers gradually replace traditional materials like porcelain and glass and become dominant at ultra high voltages, e.g., in 1000 kV ac and 800 kV dc overhead power transmissions, which are presently being developed. LÄS MER

  5. 4. Performance of Non-ceramic Insulators in Tropical Environments

    Författare :M. A. R. Manjula Fernando; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pollution; high voltage insulator; leakage current; testing;

    Sammanfattning : Non-ceramic insulators have been tested in the field and under laboratory conditions in many countries for more than three decades. Nevertheless, information about their performance in tropical environments is rather limited. Thus, this project was conducted in order to fill the gap. LÄS MER

  7. 5. Inhibited electrical discharges in air

    Författare :Anders Larsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik; elektronik; Electronics;

    Sammanfattning : Modem society requires a stable electricity supply, the reliability of which is partlydetermined by the dielectric strength of the outdoor high-voltage insulation systems.This thesis concentrates upon one particular discharge phenomenon that occurs whensuch a system is subjected to rain, namely the inhibited discharge. LÄS MER