Sökning: "breakdown voltage"

Visar resultat 1 - 5 av 75 avhandlingar innehållade orden breakdown voltage.

1. 1. Charge Accumulation in Hybrid High Voltage Insulation

   Författare :Mats Sjöberg; Chalmers tekniska högskola; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

3. 2. 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

4. 3. Fabrication and Characterization of Silicon Carbide Power Bipolar Junction Transistors

   Författare :Hyung-Seok Lee; Carl-Mikael Zetterling; Tat-Sing Chow; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silicon carbide; power device; BJT; current gain; specific on resistance RSP_ON ; breakdown voltage; forward voltage drop; surface recombination; ohmic contact.; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Sammanfattning : Silicon carbide bipolar junction transistors (BJTs) are attractive power switching devices because of the unique material properties of SiC with high breakdown electric field, high thermal conductivity and high saturated drift velocity of electrons. The SiC BJT has potential for very low specific on-resistances and this together with high temperature operation makes it very suitable for applications with high power densities. LÄS MER

5. 4. Simulation and Characterization of Silicon Carbide Power Bipolar Junction Transistors

   Författare :Benedetto Buono; Mikael Östling; Gunnar Malm; Martin Domeij; Lothar Frey; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silicon carbide; power device; BJT; diode; simulation; characterization; current gain; on-resistance; breakdown voltage; forward voltage drop; degradation; SRA - ICT; SRA - Informations- och kommunikationsteknik;

   Sammanfattning : The superior characteristics of silicon carbide, compared with silicon, have suggested considering this material for the next generation of power semiconductor devices. Among the different power switches, the bipolar junction transistor (BJT) can provide a very low forward voltage drop, a high current capability and a fast switching speed. LÄS MER

7. 5. Theoretical and Experimental Studies of the Formation of Ionized Gases in Spark Ignition Engines

   Författare :Raymond Reinmann; Förbränningsfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Thermal Ionization; Calorimetry; Interferometry; Spark Ignition Engine; Current and Voltage Measurements; Engine Control.; fluid dynamics; Gases; plasmas; Gaser; plasma; fluiddynamik; Breakdown; Arc; Glow; Flame Ionization; Chemi-Ionization; Spark; Townsend; Fysicumarkivet A:1998:Reinmann;

   Sammanfattning : The processes that govern the formation, existence and consumption of ions in gases have been studied both experimentally and theoretically. The aim of the work is targeted at increasing the understanding of these phenomena in the working gases inside an engine. LÄS MER