Sökning: "HVDC transmission"

Visar resultat 41 - 45 av 60 avhandlingar innehållade orden HVDC transmission.

  1. 41. Fundamental Control Performance Limitations for Interarea Oscillation Damping and Frequency Stability

    Författare :Joakim Björk; Karl H. Johansson; Lennart Harnefors; Joe H. Chow; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power system control; HVDC transmission control; interarea oscillations; power oscillation damping; small-signal stability; fundamental control limitations; frequency stability; hydro power; wind power; non-minimum phase; zero dynamics; eigenvalue analysis; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : With the transition towards renewable energy and the deregulation of the electricity markets, the power system is changing. Growing electricity demand and more intermittent power production increase the need for transfer capacity. Lower inertia levels due to a higher share of renewables increase the need for fast frequency reserves (FFR). LÄS MER

  3. 42. Methods for Synchrophasor-Based Power SystemInstability Detection and HVDC Control

    Författare :Rujiroj Leelaruji; Luigi Vanfretti; Jean Mahseredjian; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wide-Area Monitoring Protection and Control Systems; Synchrophasor applications; Wide-Area Voltage Instability Detection; Wide-Area EarlyWarning Systems; Automatic Voltage Stabilizer;

    Sammanfattning : The recent availability Phasor Measurement Unit (PMU) functionalities in relay technology has opened up new opportunities for power system protection, allowing this microprocessor-based technology to be used beyond traditional protection purposes. This technology now also considers the computation and communication mechanisms that allow the transmission of synchronized phasor measurements. LÄS MER

  4. 43. Surface Charge Dynamics on Polymeric Insulating Materials for High Voltage Applications

    Författare :Shahid Alam; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC insulation.; gas neutralization; decay rate; Surface charging; electrical conductivity; surface potential; charge transport; ambient pressure;

    Sammanfattning : To meet increasing demands in electric energy, it is essential to enhance production of electricity from renewable energy sources (solar, wind and hydro). Such generation sites, however, are usually separated from consumption sites by long distances. LÄS MER

  5. 44. Polyethylene Blends, a Material Concept for Future HVDC-cable Insulation

    Författare :Mattias Andersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polymer blends; nanocomposites; polyethylene; conductivity; thermomechanical properties; High-voltage insulation; tie-chain;

    Sammanfattning : High-voltage cables are a critical component of tomorrow’s power grids that seamlessly integrate hydro, wind and solar power. Further improvements in transmission capacity of both high-voltage alternating- and direct-current, HVAC and HVDC, cables are likely reached through improved insulation materials. LÄS MER

  7. 45. Coordination of protection system and VSC-HVDC to mitigate cascading failures

    Författare :Rujiroj Leelaruji; Lennart Söder; Jianping Wang; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric power engineering; Elkraftteknik;

    Sammanfattning : The rapid development of the global economics has made power systems allover the world become large-scale interconnected grids. This increases the capabilityof power grids to transfer power over the long distance to serve the desiredpower demand with the minimum cost of operation. LÄS MER