Sökning: "Hydropower"

Visar resultat 1 - 5 av 178 avhandlingar innehållade ordet Hydropower.

  1. 1. Hydropower Area Equivalents : Reduced Models for Efficient Simulation of Large-Scale Hydropower Systems

    Författare :Evelin Blom; Lennart Söder; Arild Helseth; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Area Equivalent; Aggregation; Bilevel optimization; Large-scale hydropower; Power system simulation; Reduced model; Area-Ekvivalent; Aggregering; Två-nivå-optimering; Storskalig vattenkraft; Kraftsystemssimulering; Reducerad modell;

    Sammanfattning : With over 4000 TWh yearly electricity production worldwide, hydropower plays an important role in many power systems. Unlike many other renewable energy sources, hydropower has a certain degree of controllability and high levels of flexibility over several time scales. LÄS MER

  3. 2. Graphene as Solid Lubricant in Polymer Composites : With Application in Hydropower Bearings

    Författare :Julian Somberg; Nazanin Emami; Jan Ukonsaari; Gil Gonçalves; Sergei Glavatskih; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Graphene; Solid Lubricant; Polymer Composite; Friction; Hydropower; Machine Elements; Maskinelement;

    Sammanfattning : With a rising global demand for green energy production, hydropower plays a key role in securing a reliable and sustainable energy supply. Hydropower is the largest and most efficient renewable energy source, with an ever-increasing capacity. LÄS MER

  4. 3. The Frequency of the Frequency : On Hydropower and Grid Frequency Control

    Författare :Linn Saarinen; Urban Lundin; Per Norrlund; Bengt Carlsson; Kjetil Uhlen; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydropower; frequency control; governors; power system stability; inertia; primary control; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : Variations in the electricity consumption and production connected to the power system have to be balanced by active control. Hydropower is the most important balancing resource in the Nordic system, and will become even more important as the share of variable renewable energy sources increases. LÄS MER

  5. 4. Grid frequency stability from a hydropower perspective

    Författare :Elin Dahlborg; Per Norrlund; Urban Lundin; Linn Saarinen; Katherine Elkington; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Frequency control; frequency stability; grid codes; hydropower; inertia; Kaplan unit; model validation; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : Many AC grids suffer from decreased frequency stability due to less system inertia. This has increased the risk of large-scale blackouts. This thesis and its papers address the frequency stability problem from a hydropower perspective.Grid frequency stability assessments often require accurate system inertia estimates. LÄS MER

  7. 5. On optimal hydropower bidding in systems with wind power : Modeling the impact of wind power on power markets

    Författare :Magnus Olsson; Lennart Söder; Stein-Erik Fleten; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydropower; wind power; stochastic modeling; optimization; Electric power engineering; Elkraftteknik;

    Sammanfattning : The introduction of large amounts of wind power into power systems will increase the production uncertainties due to unforeseen wind power production variations. This will have a significant impact on the required balance management quantities. LÄS MER