Search for dissertations about: "breakdown strength"

Showing result 6 - 10 of 55 swedish dissertations containing the words breakdown strength.

2. 6. Microwave Gas and Multipactor Breakdown in Inhomogeneous Fields

   Author : Joel Rasch; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; corona; inhomogeneous fields; multipactor; Microwave breakdown;

   Abstract : Microwave gas and multipactor breakdown remains to be one of the limiting factors for the maximum power in microwave devices. Above a certain electric field strength, the so-called breakdown threshold, free electrons can multiply by making ionizing impacts with neutral gas molecules, or causing secondary emission upon impact with system surfaces. READ MORE

4. 7. Polypropylene : Morphology, defects and electrical breakdown

   Author : Sari J. Laihonen; Ulf W. Gedde; Erling Ildsten; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical engineering; polypropylene; poly propylene-stat-ethylene ; crystal structure; morphology; crystallinity; crystallization kinetics; lamellae; spherulite; defect; Kemiteknik; Chemical engineering; Kemiteknik;

   Abstract : Crystal structure, morphology and crystallization kinetics of melt-crystallized polypropylene and poly(propylene-stat-ethylene) fractions with 2.7 to 11.0 mol% of ethylene were studied by differential scanning calorimeter, wide- and small-angle X-ray scattering, polarized light microscopy, transmission electron microscopy and infrared spectroscopy. READ MORE

5. 8. Active High Voltage Insulation - A New Hybrid Insulation Concept with Dynamic and Active Features

   Author : Jörgen Blennow; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high voltage; surface charge; dielectric coating; charge accumulation; insulation; breakdown strength; covered electrodes; air-gap; dielectric barrier discharges;

   Abstract : In this thesis, the concept of a new environmental-friendly and high-performance high voltage insulation is presented. Basically, it is an electric field steering technique where the dynamic process of charge accumulation, actively and advantageously, re-distributes the electric field within an insulation system. READ MORE

6. 9. Charge Accumulation in Hybrid High Voltage Insulation

   Author : Mats Sjöberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric barrier; charge accumulation; high voltage; dielectric barrier discharge; dielectric coating; hybrid insulation; electric field distribution; discharge modelling; breakdown strength; charge conditioning;

   Abstract : This thesis deals with the novel idea of controlling the electric stress or field distribution in a hybrid air - solid-dielectric high voltage insulation by promoting accumulation of surface charges on the internal interfacial layers in the combined (hybrid) dielectric structure. Primarily, applications are expected to be found in high voltage dc systems and as a method to improve the resistance against insulation failure by overvoltages, e. READ MORE

7. 10. Topographical Impact on Space Charge Injection, Accumulation and Breakdown in Polymeric HVDC Cable Interfaces

   Author : Espen Doedens; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; interfaces; XLPE; roughness; cable peelings; polymer surfaces; space charge; field enhancement factor; PEA; DC breakdown; extruded cable; roughness enhanced charge injection; HVDC; charge injection;

   Abstract : Extruded HVDC cable systems feature a variety of interface types, for which physio-chemical properties will depend on the type of application. Such applications can be joints, terminations or the cable itself, all introducing different material combinations and manufacturing methods. READ MORE