Sökning: "electro-mechanical oscillations"

Hittade 3 avhandlingar innehållade orden electro-mechanical oscillations.

  1. 1. Power System Damping - Structural Aspects of Controlling Active Power

    Författare :Olof Samuelsson; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics and Electrical technology; controller interaction; mode controllability; mode observability; mechanical equivalent; linear differential-algebraic equations; modal analysis; active power; power system damping; electro-mechanical oscillations; Elektronik och elektroteknik; Automation; robotics; control engineering; Automatiska system; robotteknik; reglerteknik;

    Sammanfattning : Environmental and economical aspects make it difficult to build new power lines and to reinforce existing ones. The continued growth in demand for electric power must therefore to a great extent be met by increased loading of available lines. LÄS MER

  3. 2. Power System Oscillations - Detection, Estimation and Control

    Författare :Morten Hemmingsson; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Elektroteknik; oscillation; power system; damping; power swing; distance protection; detection; estimation; real-time; reactive co-variation; control; Electrical engineering; load modulation; Automation; robotics; control engineering; Automatiska system; robotteknik; reglerteknik;

    Sammanfattning : The topic of this thesis is the electro-mechanical oscillations which to some extent always are present in a power system. The demand of electric power is ever increasing. At the same time, the tolerance of disruptions in the power supply is decreasing. LÄS MER

  4. 3. Self Oscillations and Cooling of Carbon Based NEMS Devices

    Författare :Anders Nordenfelt; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nano electro-mechanics; carbon nanotubes;

    Sammanfattning : We investigate the electromechanical properties of a number of system geometries featuring a doubly clamped Carbon Nanotube or Graphene sheet with a deflection sensitive resistance and an electronic feedback in the form of a Lorentz force or an electrostatic attraction. The nanotube is subjected to a constant current- or voltage bias and it is shown that when the electro-mechanical coupling exceeds a certain critical value the system becomes unstable to self-excitations of the mechanical vibrations accompanied by oscillations in the voltage drop and current through the nanotube. LÄS MER