Sökning: "Systems engineering Electrical engineering"

Visar resultat 21 - 25 av 3255 avhandlingar innehållade orden Systems engineering Electrical engineering.

  1. 21. Detection of Partial Discharges at Fast Rising Voltages

    Författare :Thomas Hammarström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Partial discharges; cavities; repetitive voltages; high dV dt.; square like voltages; short rise time; measurements;

    Sammanfattning : The present demand for higher efficiency and flexibility in the energy sector has ledto an increased use of power electronic generated waveforms as these allow energyconversion between different frequencies including DC. The generated waveformsare usually synthesized by so called Pulse Width Modulation (PWM) techniques,where the desired waveform is approximated by a number of square shaped pulseswith a short rise time. LÄS MER

  3. 22. Coated Ferritic Stainless Steels as Interconnects in Solid Oxide Fuel Cells - Material Development and Electrical Properties

    Författare :Jan Gustav Grolig; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; SOFC; High Temperature Corrosion; ASR; Interconnects;

    Sammanfattning : Solid oxide fuel cells (SOFCs) are attracting increasing interest as devices with potentialuses in decentralized and clean electricity and heat production. Several challengeswith respect to materials have to be overcome to achieve efficiencies and life-spansthat are sufficient for long-term applications. LÄS MER

  4. 23. Modeling and Estimation of Phase Noise in Oscillators with Colored Noise Sources

    Författare :M Reza Khanzadi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phase Noise Model; Bayesian Cramer-Rao Bound; Voltage-controlled Oscillator; Extended Kalman Filter Smoother; Maximum a Posteriori Estimator; Colored Phase Noise; Oscillator Phase Noise; Phase-Locked Loop; Mean Square Error.;

    Sammanfattning : The continuous increase in demand for higher data rates due to applications with massive number of users motivates the design of faster and more spectrum efficient communication systems. In theory, the current communication systems must be able to operate close to Shannon capacity bounds. LÄS MER

  5. 24. Airborne Wind Energy - to fly or not to fly?

    Författare :Elena Malz; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis investigates crosswind Airborne Wind Energy Systems (AWESs) in terms of power production and potential role in future electricity generation systems. The perspective ranges from the small scale, modelling AWE as a single system, to the large, implementing AWESs in regional electricity systems. LÄS MER

  7. 25. mm-Wave Data Transmission and Measurement Techniques: A Holistic Approach

    Författare :Dhecha Nopchinda; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; estimation theory; data transmission experiment; spectral efficiency; microwave network analysis; communication system; millimeter wave mm-wave system; mutual coupling effects; spectrally efficient frequency division multiplexing SEFDM ; vector network analyzer; wideband measurement.; coherent optical system; impairment compensation algorithm; identification theory; multiplier based transmitter; digital signal processing; Active load pull; linear measurement technique;

    Sammanfattning : The ever-increasing demand on data services places unprecedented technical requirements on networks capacity. With wireless systems having significant roles in broadband delivery, innovative approaches to their development are imperative. LÄS MER