Sökning: "high blocking voltage"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden high blocking voltage.

  1. 1. Efficient Modeling of Modular Multilevel Converters for HVDC Transmission Systems

    Detta är en avhandling från Stockholm : KTH Royal Institute of Technology

    Författare :Noman Ahmed; KTH.; [2018]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-Voltage dc; Modular Multilevel Converter; Voltage-Source Converter; HVDC Grids; Multiterminal DC Systems; Hybrid HVDC Breaker; Modeling; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The drive towards getting more and more electrical energy from renewable sources, requires more efficient electric transmission systems. A stronger grid, with more controllability and higher capacity, that can handle power fluctuations due to a mismatch between generation and load is also needed. LÄS MER

  2. 2. Junction Barrier Schottky Rectifiers in Silicon Carbide

    Detta är en avhandling från Kista : Mikroelektronik och informationsteknik

    Författare :Fanny Dahlquist; KTH.; [2002]
    Nyckelord :silicon carbide; JBS rectifier; Junction Barrier Schottky JBS ; Schottky rectifier; MPS rectifier; power rectifier; punch-through design; power loss; high blocking voltage;

    Sammanfattning : .... LÄS MER

  3. 3. Growth and characterization of SiC and GaN

    Detta är en avhandling från Linköping : Linköping University Electronic Press

    Författare :Rafal Ciechonski; Linköpings universitet.; Linköpings universitet.; [2007]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SiC; GaN; Deep level transient spectroscopy; Minority Carrier Transient Spectroscopy; Hall effect; Cathodoluminescence; Scanning electron microscopy; Atomic Force microscopy; sublimation growth; MOCVD; heterostructures; High Electron Mobility transistor; point defects; TECHNOLOGY Engineering physics Material physics with surface physics; TEKNIKVETENSKAP Teknisk fysik Materialfysik med ytfysik;

    Sammanfattning : At present, focus of the SiC crystal growth development is on improving the crystalline quality without polytype inclusions, micropipes and the occurrence of extended defects. The purity of the grown material, as well as intentional doping must be well controlled and the processes understood. LÄS MER

  4. 4. On Design of a Compact Primary Switched Conversion System for Electric Railway Propulsion

    Detta är en avhandling från Stockholm : KTH

    Författare :Tommy Kjellqvist; KTH.; [2009]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Isolated AC DC converter; Mutual commutation; Soft Switching; Cyclo converter; Medium-Frequency Transformer; Electric Railway Propulsion; TECHNOLOGY Electrical engineering; electronics and photonics Electrical engineering; TEKNIKVETENSKAP Elektroteknik; elektronik och fotonik Elektroteknik;

    Sammanfattning : In this thesis, a compact and light primary switched conversion system for AC-fed railway propulsion is investigated. It is characterized by soft switching of all converter stages and a source commutated primary converter comprising series connected valves. LÄS MER

  5. 5. Simulation and Electrical Evaluation of 4H-SiC Junction Field Effect Transistors and Junction Barrier Schottky Diodes with Buried Grids

    Detta är en avhandling från Stockholm : KTH Royal Institute of Technology

    Författare :Jang-Kwon Lim; KTH.; [2015]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Silicon carbide SiC ; junction field-effect transistors JFETs ; junction barrier schottky diode JBS ; schottky barrier diode SBD ; buried-grid BG technology; simulation; implantation; epitaxial growth; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Silicon carbide (SiC) has higher breakdown field strength than silicon (Si), which enables thinner and more highly doped drift layers compared to Si. Consequently, the power losses can be reduced compared to Si-based power conversion systems. Moreover, SiC allows the power conversion systems to operate at high temperatures up to 250 oC. LÄS MER