Sökning: "Active damping"

Visar resultat 1 - 5 av 44 avhandlingar innehållade orden Active damping.

  1. 1. A study of active-passive damping treatments

    Författare :Hélène Illaire; Chalmers University of Technology; []
    Nyckelord :active vibration control; damping mechanisms; active constrained layers;

    Sammanfattning : Active Constrained Layer (ACL) treatment is a vibration-damping treatment which consists of a viscoelastic layer constrained by an actuator. It dissipates energy simultaneously by the shearing of the viscoelastic layer and by the action of the actuator. LÄS MER

  2. 2. Towards semi-automation of forestry cranes : automated trajectory planning and active vibration damping

    Författare :Szabolcs Fodor; Leonid Freidovich; Carlos Vázquez; Anton Shiriaev; Torben Ole Andersen; Umeå universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Forestry; forwarder cranes; semi-automation; slewing actuator; automated trajectory planning; oscillations; inner boom actuator; active vibration damping; frequency estimation; input shaping control technique; H2-optimal control;

    Sammanfattning : Forests represent one of the biggest terrestrial ecosystems of Earth, that can produce important raw renewable materials such as wood with the help of sun, air and water. To efficiently extract these raw materials, the tree harvesting process is highly mechanized in developed countries, meaning that advanced forestry machines are continuously used to fell, to process and to transport the logs and biomass obtained from the forests. LÄS MER

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

    Författare :Olof Samuelsson; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 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

  4. 4. Active Junction Control and Piezoelectric Hybrid Damping for Improving the Acoustic Performance of Lightweight Structures

    Författare :Jonas Svensson; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; Hybrid passive-active control; Piezoelectric shunt damping; Sound radiation; Active junction control;

    Sammanfattning : Weight reduction is a key factor in lowering the fuel consumption and thereby the greenhouse emissions from vehicles. However, reducing the weight normally results in a deterioration of the acoustic performance. Thus, the purpose of this thesis is to investigate damping treatments for lightweight vehicle panels. LÄS MER

  5. 5. Enhanced Active Resonant DC Circuit Breakers for HVDC Grids

    Författare :Tim Augustin; Hans-Peter Nee; Marley Becerra; Jürgen Biela; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Active damping; Actuator; DC circuit breakers; DC grid; DC power systems; Fast mechanical switch; Fault handling strategy; Gas discharge devices; HVDC; HVDC circuit breakers; Multilevel converters; Multiterminal HVDC; Power transmission; Spark gaps; Thomson-coil actuator; Vacuum interrupter; Voltage Source Converter VSC ; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : High-voltage DC (HVDC) grids are considered promising for the electricity grid expansion required to integrate renewable energy sources into the existing infrastructure. DC fault currents increase rapidly and lack a current zero crossing. LÄS MER