Sökning: "hydropower generator"

Visar resultat 1 - 5 av 25 avhandlingar innehållade orden hydropower generator.

  1. 1. Hydropower generator and power system interaction

    Författare :Johan Bladh; Urban Lundin; Rafael Escarela-Perez; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Amortisseur windings; applied voltage test; automatic voltage regulators; damper windings; damping torque; empirical modelling; equivalent circuits; excitation control; finite element method; hydropower generators; power system restoration; power system stability; synchronous machines; self excitation; shaft torque amplification; short circuit test; single machine infinite bus; slip test; standstill frequency response test; subsynchronous oscillations; synchronising torque; synchronous generators; torsional interaction.; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : After decades of routine operation, the hydropower industry faces new challenges. Large-scale integration of other renewable sources of generation in the power system accentuates the role of hydropower as a regulating resource. LÄS MER

  3. 2. Electric Energy Conversion Systems : Wave Energy and Hydropower

    Författare :Karin Thorburn; Mats Leijon; Petra Lundström; Uppsala universitet; []
    Nyckelord :Engineering physics; Ocean wave power; renewable energy; linear generator; farm simulation; Teknisk fysik;

    Sammanfattning : Electric energy conversion is an important issue in today's society as our daily lives largely depend on the supplies of energy. Two energy sources are studied for conversion in the present thesis, ocean waves and hydropower. The work focuses on the generator and the transmission of its output to the electric grid. LÄS MER

  4. 3. 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

  5. 4. Measurement and modelling of unbalanced magnetic pull in hydropower generators

    Författare :Mattias Wallin; Urban Lundin; Antero Arkkio; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Damper winding; eddy currents; field winding short circuit; finite element method; hydropower generator; parallel circuits; rotor eccentricity; salient poles; synchronous generators; synchronous machines; UMP; unbalanced magnetic pull.; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Sammanfattning : Hydropower research is often perceived to be an old and exhausted field of study but with ageing equipment and the need for more intermittent operation caused by an increased share of other renewable energy sources new challenges lie ahead.The main focus of this dissertation are the electromagnetic forces resulting from nonuniform air gap flux, whether it be caused by rotor eccentricity or a faulty field winding. LÄS MER

  7. 5. Modelling and analysis of hydropower generator rotors

    Författare :Rolf Gustavsson; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Datorstödd maskinkonstruktion; Computer Aided Design;

    Sammanfattning : In almost all production of electricity the rotating machines serves as an important part of the energy transformation system. In hydropower units, a hydraulic turbine connected to a generator converts the potential energy stored in the water reservoir into electrical energy in the generator. LÄS MER