Sökning: "breakdown voltage"

Visar resultat 16 - 20 av 75 avhandlingar innehållade orden breakdown voltage.

  1. 16. Protection Strategies to Mitigate Major Power Systems Breakdowns

    Författare :Mattias Jonsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; system protection schemes; transient instability; distance protection; power swing detectors; voltage instability; generator coherency; wide area protection; out-of-step protection;

    Sammanfattning : This thesis deals with new methods to improve the performance of power system protection in the case of voltage- and transient instability. These methods are designed primarily to mitigate power system breakdown. Relay algorithms are proposed where conventional distance protection is combined with additional relay criteria. LÄS MER

  3. 17. Design, Processing and Characterization of Silicon Carbide Diodes

    Författare :Uwe Zimmermann; KTH; []
    Nyckelord :silicon carbide; diodes; high-voltage; dislocations; electronics;

    Sammanfattning : Electronic power devices made of silicon carbide promisesuperior performance over today's silicon devices due toinherent material properties. As a result of the material'swide band gap of 3. LÄS MER

  4. 18. Design, Fabrication and Characterization of GaN HEMTs for Power Switching Applications

    Författare :Björn Hult; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DCIT; SCE; high voltage; isolation; ‘buffer-free’; gate dielectric; GaN HEMT; passivation; DIBL;

    Sammanfattning : The unique properties of the III-nitride heterostructure, consisting of gallium nitride (GaN), aluminium nitride (AlN) and their ternary compounds (e.g. AlGaN, InAlN), allow for the fabrication of high electron mobility transistors (HEMTs). LÄS MER

  5. 19. 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

  7. 20. Electrical Characterization of Silicon Nanogaps

    Författare :Jonas Berg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic molecules; Molecular electronics; Surface leakage currents; Low-frequency noise; Soft breakdown; TSRAM; Resonant tunneling diodes; Selective etching; Silicon nanogaps; Nanocontacts;

    Sammanfattning : We have designed and manufactured silicon nanogaps aimed at electrically interfacing molecules, utilizing the precision thickness control in an oxidation process. An insulating layer was formed on a silicon wafer, and then polysilicon was deposited on top. LÄS MER