Sökning: "hydropower"

Visar resultat 1 - 5 av 170 avhandlingar innehållade ordet hydropower.

  1. 1. 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 :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; 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

  3. 2. Grid frequency stability from a hydropower perspective

    Författare :Elin Dahlborg; Per Norrlund; Urban Lundin; Linn Saarinen; Katherine Elkington; Uppsala universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; 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

  4. 3. 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 :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; 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

  5. 4. Tribology of self-lubricating polymer composites for hydropower applications

    Författare :Maria Rodiouchkina; Jens Hardell; Kim Berglund; Jan Ukonsaari; Michał Wasilczuk; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polymer composites; hydropower; sliding wear; sliding friction; self-lubricating; transfer layers; material characterization; surface analysis; high contact pressure; low sliding speed; Machine Elements; Maskinelement;

    Sammanfattning : The ongoing global climate crisis and its impacts calls for urgent actions, such as significant reduction of CO2 emissions by introducing more renewable energy. This has led to a rapid integration of variable power sources, such as wind and solar power, into the electricity systems. LÄS MER

  7. 5. Insights from modeling renewable electricity systems and developing hydropower models

    Författare :Hanna Ek Fälth; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; renewables; electricity systems; hydropower; nuclear; modeling; Europe; MENA; transmission; available land;

    Sammanfattning : One strategy for reaching a carbon-neutral electricity system is a large-scale deployment of wind and solar power. However, electricity systems with high shares of wind and solar power rely on other technologies, e.g. LÄS MER