Sökning: "harmonic load"

Visar resultat 1 - 5 av 43 avhandlingar innehållade orden harmonic load.

  1. 1. SiC Varactors for Dynamic Load Modulation of Microwave Power Amplifiers

    Författare :Christer Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear characterization; varactors; active load-pull; power; microwave; amplifier; dynamic load modulation; SiC; energy efficiency;

    Sammanfattning : The rapid consumer adoption of mobile services is leading to an exponential growth in wireless data traffic. In order to accommodate more concurrent high data-rate users, the required complexity of transmitting radio base station (RBS) power amplifiers (PAs) is increasing. LÄS MER

  3. 2. Slotless High-Performance Electric Drives : Harmonic Loss Analysis, Sensorless Control, and Inverter Design

    Författare :Jonas Millinger; Oskar Wallmark; Juliette Soulard; Zi-Qiang Zhu; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Finite-element analysis; harmonic losses; sensorless control; slotless motor drives; thermal modeling; wide-bandgap inverter; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Electric motor drives are a cornerstone for many fundamental functions in today’s society, and their expected dominance within the transport sector is considered one of the main keys to abate global warming. Subsequently, the incentives for improved performance of electric motor drives cannot be sufficiently emphasized. LÄS MER

  4. 3. On the dynamics of footbridges : A theoretical approach and a comparison between running and walking loads

    Författare :Daniel Colmenares; Raid Karoumi; Andreas Andersson; Mahir Ülker Kaustell; Pedro Museros Romero; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; footbridges; dynamics; human induced loads; human structure interaction; harmonic load; continuous beam; gångbroar; dynamik; fotgängarlast; samverkan mellan fotgängare och bro; harmonisk last; kontinuerlig balk.; Structural Engineering and Bridges; Bro- och stålbyggnad;

    Sammanfattning : The dynamic behaviour of lightweight footbridges is often susceptible to HumanInduced Loads (HILs). Generally HILs are taken into account as moving harmonicfunctions in which the loading frequency represents the step frequency of the pedestrians. LÄS MER

  5. 4. High Efficiency Microwave Amplifiers and SiC Varactors Optimized for Dynamic Load Modulation

    Författare :Christer Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear measurements; power amplifiers; load modulation; GaN; SiC; varactors; HEMT; wide bandgap technology; energy efficiency;

    Sammanfattning : The increasing use of mobile networks as the main source of internet connectivity is creating challenges in the infrastructure. Customer demand is a moving target and continuous hardware developments are necessary to supply higher data rates in an environmentally sustainable and cost effective way. LÄS MER

  7. 5. Control and Analysis of Pulse-Modulated Systems

    Författare :Stefan Almér; Ulf Jönsson; Gilead Tadmor; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pulse-width modulation; Periodic systems; Stability analysis; Harmonic analysis; Lyapunov methods; Dynamic phasors; Harmonic transfer function; Switched mode power converters; Sampled data modeling; H-infinity synthesis; Optimization; systems theory; Optimeringslära; systemteori;

    Sammanfattning : The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. LÄS MER