Sökning: "DC breakdown"

Visar resultat 1 - 5 av 26 avhandlingar innehållade orden DC breakdown.

1. 1. Device Technology Based on High Temperature Superconductors and Microwave Breakdown in Gases

   Författare :Martin Löfgren; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; distortion; penetration depth; surface resistance; transmit-receive switch; coupled-grain model; high-power; microwave; pulse; surface impedance; breakdown; propagation; modulator; air; superconductor; transmission line; resonator; coplanar waveguide; plasma;

   Sammanfattning : This thesis deals with two separate fields of microwave technology. The first section treats microwave characterization and applications of high temperature superconducting (HTS) thin films, while the second section treats microwave breakdown in transmit-receive (TR) switches and in air. Within the first section, four main topics are adressed. LÄS MER

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

   Författare :Espen Doedens; Chalmers tekniska högskola; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

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

   Författare :Sari J. Laihonen; Ulf W. Gedde; Erling Ildsten; KTH; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

5. 4. Characterization of Different Interface Types for HVDC Extruded Cable Applications

   Författare :Espen Doedens; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polymer surfaces; cable peelings; HVDC; Roughness; Charge injection; XLPE; Field enhancement factors; Schottky injection; DC breakdown; Voltage decay; interfaces; Fowler-Nordheim injection; extruded cable; Roughness assisted charge injection.; Charge decay;

   Sammanfattning : In extruded HVDC cable systems a variety of interface types can be found, and the interfacial properties depend on the application within the system. Such applications can be joints, terminations or the cable itself and they will all have different material combinations and manufacturing methods. LÄS MER

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

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

   Sammanfattning : 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. LÄS MER