Sökning: "HVDC transmission"

Visar resultat 11 - 15 av 60 avhandlingar innehållade orden HVDC transmission.

  1. 11. Protection for Multiterminal HVDC Grids - A Digital Contribution

    Författare :Ilka Jahn; Staffan Norrga; Hans-Peter Nee; Dirk Westermann; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC transmission; power system protection; IED; real-time systems; test bench; field programmable gate array; open-source hardware; open-source software; power engineering education; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The aim of this thesis is to (1) enhance understanding of mechanisms that are important for the protection of high-voltage direct-current (HVDC) grids, and (2) suggest possible technical solutions. To that end, digital technologies were used both in simulation, as well as in a laboratory environment. LÄS MER

  3. 12. Coordinated Control of HVDC Links in Transmission Systems

    Författare :Robert Eriksson; Lennart Söder; Kjetil Uhlen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; coordinated control; dynamic security; exact-feedback linearization; feedforward control; HVDC poser modulation; Electric power engineering; Elkraftteknik;

    Sammanfattning : Dynamic security limits the power transfer capacity between regions and therefore has an economic impact. The power modulation control of high-voltage direct current (HVDC) links can improve the dynamic security of the power system. LÄS MER

  4. 13. Grid connection of offshore renewable energy sources

    Författare :Christoffer Fjellstedt; Karin Thomas; Mats Leijon; Daniel Månsson; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Grid connection; Electronic filters; Power transformers; Offshore collection grids; HVDC transmission; HVAC transmission; Marine current energy; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : In order to achieve net zero emissions from the electricity sector, the proportion of renewable energy sources connected to the electrical grid needs to be increased significantly in the coming years. Established renewable energy sources, such as wind power and solar power, will certainly be crucial in achieving this. LÄS MER

  5. 14. Polyethylene – metal oxide particle nanocomposites for future HVDC cable insulation : From interface tailoring to designed performance

    Författare :Dongming Liu; Ulf Gedde; Mikael Hedenqvist; Richard Olsson; Linda Schadler; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC; electrical insulation; core-shell nanoparticles; surface modification; silane chemistry; nanocomposites; polyethylene; adsorption; long-term stability; interface; particle dispersion; cavitation; conductivity; HVDC; elektrisk isolation; ytmodifiering; silankemi; nanokompositer; polyeten; adsorption; långtidsstabilitet; ytskikt; partikeldispergering; kavitation; ledningsförmåga; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Low-density polyethylene (LDPE) nanocomposites containing metal oxide nanoparticles are considered as promising candidates for insulating materials in future high-voltage direct-current (HVDC) cables. The significant improvement in dielectric properties compared with unfilled polymer is attributed to the large and active interface between the nanoparticles and the polymer. LÄS MER

  7. 15. The synthesis, surface modification and use of metal-oxide nanoparticles in polyethylene for ultra-low transmission-loss HVDC cable insulation materials

    Författare :Amir Masoud Pourrahimi; Ulf W. Gedde; Alexander Bismarck; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polyethylene; metal-oxide nanoparticles; heat treatment; surface coating; humidity resistance; interfacial adhesion; nanocomposite; HVDC insulation; polyeten; metalloxid nanopartiklar; värmebehandling; ytmodifiering av partiklarna; fukt inverkan; gränsskiktsvidhäftning; nanokomposit; HVDC isolering; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Polyethylene composites which contain low concentrations of metal-oxide nanoparticles e.g. ZnO and MgO are emerging materials for the use in insulations of extruded high-voltage direct-current (HVDC) cables. LÄS MER