Sökning: "High surface conductivity"

Visar resultat 1 - 5 av 244 avhandlingar innehållade orden High surface conductivity.

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

    Författare :Shahid Alam; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC insulation.; gas neutralization; decay rate; Surface charging; electrical conductivity; surface potential; charge transport; ambient pressure;

    Sammanfattning : 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. LÄS MER

  3. 2. Surface Stabilization and Electrochemical Properties from a Theoretical Perspective

    Författare :Daniel Petrini; Karin Larsson; Jan-Otto Carlsson; Martin Stutzmann; Uppsala universitet; []
    Nyckelord :Inorganic chemistry; DFT; Diamond; High surface conductivity; Surface reactivity; c-BN; Oorganisk kemi;

    Sammanfattning : Diamond and cubic boron nitride surfaces have extreme properties that can be exploited in novel tribological, electrochemical and electronic applications. Normally insulating diamond surfaces can exhibit high surface conductivities due to hydrogen termination and the nature of the surrounding atmosphere. LÄS MER

  4. 3. 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

  5. 4. Fundamentals of Polyethylene Composites for HVDC Cable Insulation – Interfaces and Charge Carriers

    Författare :Mattias E. Karlsson; Richard Olsson; Mikael Skrifvars; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polyethylene; nanocomposites; HVDC; conductivity; metal oxide; nanoparticles; surface functionality; polyeten; nanokompositer; HVDC; konduktivitet; metalloxider; nanopartiklar; ytfunktionalitet; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Power transmission over long distances by using high voltage direct current (HVDC) cables is important for the transition from fossil energy to using renewable energy sources, e.g. wind, solar and water. LÄS MER

  7. 5. Polyethylene – metal oxide particle nanocomposites for future HVDC cable insulation : From interface tailoring to designed performance

    Författare :Dongming Liu; Ulf Gedde; Mikael Hedenqvist; Richard Olsson; Linda Schadler; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC; electrical insulation; core-shell nanoparticles; surface modification; silane chemistry; nanocomposites; polyethylene; adsorption; long-term stability; interface; particle dispersion; cavitation; conductivity; HVDC; elektrisk isolation; ytmodifiering; silankemi; nanokompositer; polyeten; adsorption; långtidsstabilitet; ytskikt; partikeldispergering; kavitation; ledningsförmåga; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Low-density polyethylene (LDPE) nanocomposites containing metal oxide nanoparticles are considered as promising candidates for insulating materials in future high-voltage direct-current (HVDC) cables. The significant improvement in dielectric properties compared with unfilled polymer is attributed to the large and active interface between the nanoparticles and the polymer. LÄS MER