Search for dissertations about: "hvdc thesis"

Showing result 16 - 20 of 102 swedish dissertations containing the words hvdc thesis.

  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. Distributed Control of HVDC Transmission Grids

    Author : Davood Babazadeh; Lars Nordström; Oriol Gomis; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; co-simulation; cyber-physical system; DC slack bus; distributed control; HVDC grids; power injection; topology processor; wind farms; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Recent issues such as priority access of renewable resources recommended by European energy directives and increase the electricity trading among countries lead to new requirements on the operation and expansion of transmission grids. Since AC grid expansions are limited by legislative issues and long distance transmission capacity, there is a considerable attention drawn to application of HVDC transmission grids on top of, or in complement to, existing AC power systems. READ MORE