Search for dissertations about: "DISCHARGE SUPPRESSION"
Showing result 1 - 5 of 8 swedish dissertations containing the words DISCHARGE SUPPRESSION.
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1. Electrical Characterization of Partial Discharge Resistant Enamel Insulation
Abstract : Adjustable speed drives for rotating machines have become increasingly popular as they provide possibilities of smooth and accurate process control as well as for energy savings. In such systems, due to the fact that the voltage applied at terminals of motor windings is no longer purely sinusoidal but characterized by a high content of harmonics, the appearing electrical and thermal stresses yield premature failures of the winding insulation, mainly because of an increased partial discharge (PD) activity. READ MORE
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2. Scanning Probe Microscopy: Design and Applications
Abstract : A compact scanning tunneling microscope (STM) and a scanning ion-conductance microscope (SICM) has been constructed. The concentric microscope head was built around a commercial piezoelectric inchworm motor that was used for coarse positioning. The microscope has a high resonance frequency (9.6 kHz), low noise (0. READ MORE
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3. Reactive High Power Impulse Magnetron Sputtering of Metal Oxides
Abstract : The work presented in this thesis deals with reactive magnetron sputtering processes of metal oxides with a prime focus on high power impulse magnetron sputtering (HiPIMS). The aim of the research is to contribute towards understanding of the fundamental mechanisms governing a reactive HiPIMS process and to investigate their implications on the film growth. READ MORE
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4. Detection of Partial Discharges at Fast Rising Voltages
Abstract : The present demand for higher efficiency and flexibility in the energy sector has ledto an increased use of power electronic generated waveforms as these allow energyconversion between different frequencies including DC. The generated waveformsare usually synthesized by so called Pulse Width Modulation (PWM) techniques,where the desired waveform is approximated by a number of square shaped pulseswith a short rise time. READ MORE
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5. Charge transport in polymer-based insulating materials for high voltage applications: effect of single- and multi-layered structures
Abstract : Polymer composites have been widely employed as electrical insulating materials for high voltage components and devices such as power cables, gas-insulated systems, rotating machines, line and post insulators, etc. Such materials are usually made by introducing inorganic oxides (SiO2, TiO2, Al2O3, MgO) into polymeric matrices e.g. READ MORE