Search for dissertations about: "dielectric relaxation measurement"

Found 2 swedish dissertations containing the words dielectric relaxation measurement.

  1. 1. Dielectric relaxation spectroscopy of chiral smectic liquid crystals

    Author : Fathi M. Gouda; [1992]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; dielectric relaxation measurement; goldstone mode; liquid crystals; soft mode; polarisation mode; perpendicular component; tilt fluctuation;

    Abstract : .... READ MORE

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

    Author : Björn Sonerud; [2010]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; arbitrary voltage waveforms; partial discharge; diagnostics; dielectric response measurement; signal processing; electrical treeing; dielectric heating.;

    Abstract : 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. READ MORE