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Hittade 5 uppsatser som matchar ovanstående sökkriterier.

  1. 1. Field Current Control for the Damping of Rotor Oscillations and for the Alternative Start of Synchronous Machines : Further Innovative Applications of Field Current Active Control besides UMP-Compensation

    Master-uppsats, Uppsala universitet/Institutionen för teknikvetenskaper

    Författare :Roberto Felicetti; [2018]
    Nyckelord :asynchronous start; current control; damping bars; damper winding; d-axis; q-axis; hunting; natural frequency; Park s reference frame; rotor back-EMF; rotor oscillations; synchronous motor;

    Sammanfattning : The possibility to save energy in synchronous machines operation by dismissing d-axis damping bars and surrogating them with active excitation current control in sectored field winding is proved. In particular a way to recover the energy of rotor oscillations during power regulation is shown by means of a studycase generator whereas a self-starting machine is analytically and numerically designed in view of its next construction and test. LÄS MER

  3. 2. Damper Winding Fault Detection in Synchronous Machines

    Uppsats för yrkesexamina på avancerad nivå,

    Författare :Fredrik Holmgren; [2016]
    Nyckelord :Fault detection; condition monitoring; motor diagnostics; synchronous machines; synchronous motors; electrical machines; motor drives; damper winding; damper bars;

    Sammanfattning : This thesis aims to identify methods for detection of damper winding faults in synchronous machines (SMs) powered by variable frequency drives (VFDs). The problem of failing damper windings has received attention after reports of serious damage which have been discovered during maintenance checks. LÄS MER

  4. 3. Synchronous generator rotor position estimation from stator and rotor terminal currents and voltages

    Master-uppsats, KTH/Skolan för elektro- och systemteknik (EES)

    Författare :Wille Kiuru; [2016]
    Nyckelord :;

    Sammanfattning : This thesis presents an alternative method for measuring the rotor position of a synchronousgenerator, without the use of sensors to measure the rotor position. The method uses thecurrent and voltage measurements on the stator and rotor terminals from the protectionrelays. LÄS MER

  5. 4. Force Feedback Control of a Semi-Active Shock Absorber

    Master-uppsats, Linköpings universitet/Reglerteknik; Linköpings universitet/Tekniska högskolan

    Författare :Per Svennerbrandt; [2014]
    Nyckelord :Force feedback control; semi-active dampers; damper modeling; exact linearization;

    Sammanfattning : Semi-active suspension systems promise to significantly reduce the necessary trade-off be-tween handling and passenger comfort present in conventional suspension systems by enabling active chassis and wheel control. Öhlins Racing AB have developed a semi-active suspension technology known as CES, Continuously controlled Electronic Suspension, based on solenoid control valves which are integrated into specially designed hydraulic dampers, and are currently developing control and estimation systems which will enable their application in advanced motorcycle suspensions. LÄS MER

  7. 5. Dämplindningens inverkan på spänningens kurvform i en vattenkraftsgenerator

    Uppsats för yrkesexamina på avancerad nivå, Elektricitetslära

    Författare :Marielle Perup; [2010]
    Nyckelord :generator; övertoner; tomgångsspänning; dämplindning; dämpkrets; dämpstavar;

    Sammanfattning : Harmonics are a well-known problem that has to be dealt with in the design of thegenerator. Internationally accepted standards limits the amount of harmonics allowedin the no-load voltage. These limits can be difficult to fulfill with integral slot winding,where the number of slots per pole and phase is an integer. LÄS MER