Search for dissertations about: "HVDC"

Showing result 16 - 20 of 102 swedish dissertations containing the word HVDC.

  2. 16. Fundamentals of Polyethylene Composites for HVDC Cable Insulation – Interfaces and Charge Carriers

    Author : Mattias E. Karlsson; Richard Olsson; Mikael Skrifvars; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polyethylene; nanocomposites; HVDC; conductivity; metal oxide; nanoparticles; surface functionality; polyeten; nanokompositer; HVDC; konduktivitet; metalloxider; nanopartiklar; ytfunktionalitet; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : Power transmission over long distances by using high voltage direct current (HVDC) cables is important for the transition from fossil energy to using renewable energy sources, e.g. wind, solar and water. READ MORE

  4. 17. Characterization of Conduction and Polarization Properties of HVDC Cable XLPE Insulation Materials

    Author : Hossein Ghorbani; Hans Edin; Erling Ildstad; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC insulation; power cable insulation; cross-linked polyethylene insulation; conductivity; dielectric losses; space charge; HVDC isolation; kraftkabel isolation; tvärbunden polyeten isolationsmaterial; elektrisk ledningsförmåga; dielektriska förluster; rymdladdning; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Since its first introduction in 1998, extruded direct current (DC) cable technology has been growing rapidly leading to many cable system installations with operation voltages up to 320 kV. Cable manufacturers invest heavily on technology development in this field and today extruded DC cable systems for operation voltages as high as 525 kV are commercially available. READ MORE

  5. 18. Efficient Modeling of Modular Multilevel Converters for HVDC Transmission Systems

    Author : Noman Ahmed; Hans-Peter Nee; Tim Green; KTH; []
    Keywords : 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;

    Abstract : 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. READ MORE

  6. 19. 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

  7. 20. VSC-HVDC for Industrial Power Systems

    Author : Cuiqing Du; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; voltage dips; vector controller; VSC-HVDC; outer controller; current limit; industrial power systems.;

    Abstract : The recent developments in semiconductors and control equipment have made the voltage source converter based high voltage direct current (VSC-HVDC) feasible. Due to theuse of VSC technology and pulse width modulation (PWM) the VSC-HVDC has a number of potential advantages as compared with classic HVDC, such as short circuit current reduction, rapid and independent control of active and reactive power, etc. READ MORE