Sökning: "time-domain dielectric relaxation"

Hittade 2 avhandlingar innehållade orden time-domain dielectric relaxation.

  1. 1. Studies of Dielectric Relaxation in Solid Polymers and Composites

    Författare :Mohsen Safari Ardi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric permittivity; time-domain dielectric relaxation; composite; carbon black; poly vinylidene fluoride ; interfacial polarization; poly vinyl chloride ; coated carbon fibre; epoxy; poly methyl methacrylate ; nitrile butadiene rubber; ethylene-vinyl acetate copolymer; polyamide 6;

    Sammanfattning : Non-linear characteristics of homogeneous solid polymers and solid polymer-based composites have been studied both experimentally and theoretically. In particular experimental studies of non-linear dielectric response of six homogeneous solid polymeric materials and the influence of the composition on the properties of solid polymer-based composites with high dielectric permittivities have been carried out and a theoretical study of dipole-dipole interaction in solids based on a formulation due to P. LÄS MER

  3. 2. Characterization of Electrical Insulation Exposed to Arbitrary Voltage Waveforms

    Författare :Björn Sonerud; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; arbitrary voltage waveforms; partial discharge; diagnostics; dielectric response measurement; signal processing; electrical treeing; dielectric heating.;

    Sammanfattning : The extensive use of power electronics in power systems today gives rise to other voltage waveforms than the conventional 50/60 Hz sinusoidal and consequently other types of electric stress act on high voltage insulating materials. Previous studies has shown that Pulse Width Modulated (PWM) voltages and similar waveforms increase stress in Adjustable Speed Drives (ASD) as compared with sinusoidal waveforms and it has also been shown that partial discharge (PD) activity is intensified during PWM voltages and that rise time of square like pulses affect PD inception voltage. LÄS MER