Sökning: "symmetrical components"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden symmetrical components.

  1. 1. Three-phase unbalance of voltage dips

    Författare :Lidong Zhang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; equipment immunity test; power quality; characterisation; power systems; field measurement; voltage dips sags ; symmetrical components;

    Sammanfattning : .... LÄS MER

  3. 2. Analysis and Control Aspects of Brushless Induction Machines with Rotating Power Electronic Converters

    Författare :Naveed ur Rehman Malik; Chandur Sadarangani; Luca Peretti; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Doubly-fed induction generator; extended vector control; induction machine; internal model control; Lindmark concept; low voltage ride through; passive resistive network; rotating power electronic converter; rotating exciter; symmetrical faults; synchronous machine; unity power factor; unsymmetrical faults; vector control; wind turbines.; Järnvägsgruppen - Elsystem; Järnvägsgruppen - Elsystem;

    Sammanfattning : This thesis deals with the steady-state, dynamic and control aspects of new type of brushless configuration of a doubly-fed induction machine in which the slip rings and carbon brushes are replaced by rotating power electronics and a rotating exciter. The aim is to study the stability of this novel configuration of the generator under mechanical and grid disturbances for wind power applications. LÄS MER

  4. 3. Design of High-Speed Analog-to-Digital Converters using Low-Accuracy Components

    Författare :Timmy Sundström; Atila Alvandpour; Jan-Erik Eklund; Linköpings universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : The scaling of CMOS technologies has increased the performance of general purpose processors and DSPs. However, analog circuits designed in the same process have not been able to utilize the scaling to the same extent, suffering from reduced voltage headroom and reduced analog gain. LÄS MER

  5. 4. High-frequency noise in power grids, neutral and protective earth

    Författare :Martin Lundmark; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy Engineering; Energiteknik;

    Sammanfattning : This licentiate thesis deals with the high-frequency distortion, 1 kHz and higher, introduced into the power grid by the numbers of power converters in use today. These devices can be a source of electromagnetic interference and equipment damage despite the fact that the equipment complies product-standards testing. LÄS MER

  7. 5. Differential Protection for Arbitrary Three-Phase Power Transformers

    Författare :Zoran Gajic; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electric power systems; power transformers; differential protection; power system protection;

    Sammanfattning : This thesis describes how to provide standardized, current based, differential protection for any three-phase power transformer, including phase-shifting transformers with variable phase angle shift and transformers of all construction types and internal on-load tap-changer configurations. The use of standard transformer differential protection for such applications is considered impossible in the protective relaying standards and practices currently applied. LÄS MER